/**************************************************************************** * * * GNAT COMPILER COMPONENTS * * * * D E C L * * * * C Implementation File * * * * Copyright (C) 1992-2015, Free Software Foundation, Inc. * * * * GNAT is free software; you can redistribute it and/or modify it under * * terms of the GNU General Public License as published by the Free Soft- * * ware Foundation; either version 3, or (at your option) any later ver- * * sion. GNAT is distributed in the hope that it will be useful, but WITH- * * OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * * for more details. You should have received a copy of the GNU General * * Public License along with GCC; see the file COPYING3. If not see * * . * * * * GNAT was originally developed by the GNAT team at New York University. * * Extensive contributions were provided by Ada Core Technologies Inc. * * * ****************************************************************************/ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "hash-set.h" #include "vec.h" #include "input.h" #include "alias.h" #include "symtab.h" #include "inchash.h" #include "tree.h" #include "fold-const.h" #include "stringpool.h" #include "stor-layout.h" #include "flags.h" #include "toplev.h" #include "ggc.h" #include "target.h" #include "tree-inline.h" #include "diagnostic-core.h" #include "ada.h" #include "types.h" #include "atree.h" #include "elists.h" #include "namet.h" #include "nlists.h" #include "repinfo.h" #include "snames.h" #include "stringt.h" #include "uintp.h" #include "fe.h" #include "sinfo.h" #include "einfo.h" #include "ada-tree.h" #include "gigi.h" /* "stdcall" and "thiscall" conventions should be processed in a specific way on 32-bit x86/Windows only. The macros below are helpers to avoid having to check for a Windows specific attribute throughout this unit. */ #if TARGET_DLLIMPORT_DECL_ATTRIBUTES #ifdef TARGET_64BIT #define Has_Stdcall_Convention(E) \ (!TARGET_64BIT && Convention (E) == Convention_Stdcall) #define Has_Thiscall_Convention(E) \ (!TARGET_64BIT && is_cplusplus_method (E)) #else #define Has_Stdcall_Convention(E) (Convention (E) == Convention_Stdcall) #define Has_Thiscall_Convention(E) (is_cplusplus_method (E)) #endif #else #define Has_Stdcall_Convention(E) 0 #define Has_Thiscall_Convention(E) 0 #endif #define STDCALL_PREFIX "_imp__" /* Stack realignment is necessary for functions with foreign conventions when the ABI doesn't mandate as much as what the compiler assumes - that is, up to PREFERRED_STACK_BOUNDARY. Such realignment can be requested with a dedicated function type attribute on the targets that support it. We define FOREIGN_FORCE_REALIGN_STACK to characterize the situations where the attribute should be set. We rely on compiler configuration settings for 'main' to decide. */ #ifdef MAIN_STACK_BOUNDARY #define FOREIGN_FORCE_REALIGN_STACK \ (MAIN_STACK_BOUNDARY < PREFERRED_STACK_BOUNDARY) #else #define FOREIGN_FORCE_REALIGN_STACK 0 #endif struct incomplete { struct incomplete *next; tree old_type; Entity_Id full_type; }; /* These variables are used to defer recursively expanding incomplete types while we are processing an array, a record or a subprogram type. */ static int defer_incomplete_level = 0; static struct incomplete *defer_incomplete_list; /* This variable is used to delay expanding From_Limited_With types until the end of the spec. */ static struct incomplete *defer_limited_with; typedef struct subst_pair_d { tree discriminant; tree replacement; } subst_pair; typedef struct variant_desc_d { /* The type of the variant. */ tree type; /* The associated field. */ tree field; /* The value of the qualifier. */ tree qual; /* The type of the variant after transformation. */ tree new_type; } variant_desc; /* A hash table used to cache the result of annotate_value. */ struct value_annotation_hasher : ggc_cache_hasher { static inline hashval_t hash (tree_int_map *m) { return htab_hash_pointer (m->base.from); } static inline bool equal (tree_int_map *a, tree_int_map *b) { return a->base.from == b->base.from; } static void handle_cache_entry (tree_int_map *&m) { extern void gt_ggc_mx (tree_int_map *&); if (m == HTAB_EMPTY_ENTRY || m == HTAB_DELETED_ENTRY) return; else if (ggc_marked_p (m->base.from)) gt_ggc_mx (m); else m = static_cast (HTAB_DELETED_ENTRY); } }; static GTY ((cache)) hash_table *annotate_value_cache; static void prepend_one_attribute (struct attrib **, enum attr_type, tree, tree, Node_Id); static void prepend_one_attribute_pragma (struct attrib **, Node_Id); static void prepend_attributes (struct attrib **, Entity_Id); static tree elaborate_expression (Node_Id, Entity_Id, const char *, bool, bool, bool); static bool type_has_variable_size (tree); static tree elaborate_expression_1 (tree, Entity_Id, const char *, bool, bool); static tree elaborate_expression_2 (tree, Entity_Id, const char *, bool, bool, unsigned int); static tree elaborate_reference (tree, Entity_Id, bool, tree *); static tree gnat_to_gnu_component_type (Entity_Id, bool, bool); static tree gnat_to_gnu_param (Entity_Id, Mechanism_Type, Entity_Id, bool, bool *); static tree gnat_to_gnu_field (Entity_Id, tree, int, bool, bool); static bool is_from_limited_with_of_main (Entity_Id); static tree change_qualified_type (tree, int); static bool same_discriminant_p (Entity_Id, Entity_Id); static bool array_type_has_nonaliased_component (tree, Entity_Id); static bool compile_time_known_address_p (Node_Id); static bool cannot_be_superflat (Node_Id); static bool constructor_address_p (tree); static bool allocatable_size_p (tree, bool); static bool initial_value_needs_conversion (tree, tree); static int compare_field_bitpos (const PTR, const PTR); static bool components_to_record (tree, Node_Id, tree, int, bool, bool, bool, bool, bool, bool, bool, bool, tree, tree *); static Uint annotate_value (tree); static void annotate_rep (Entity_Id, tree); static tree build_position_list (tree, bool, tree, tree, unsigned int, tree); static vec build_subst_list (Entity_Id, Entity_Id, bool); static vec build_variant_list (tree, vec , vec ); static tree validate_size (Uint, tree, Entity_Id, enum tree_code, bool, bool); static void set_rm_size (Uint, tree, Entity_Id); static unsigned int validate_alignment (Uint, Entity_Id, unsigned int); static void check_ok_for_atomic_type (tree, Entity_Id, bool); static tree create_field_decl_from (tree, tree, tree, tree, tree, vec ); static tree create_rep_part (tree, tree, tree); static tree get_rep_part (tree); static tree create_variant_part_from (tree, vec , tree, tree, vec ); static void copy_and_substitute_in_size (tree, tree, vec ); static void add_parallel_type_for_packed_array (tree, Entity_Id); static const char *get_entity_char (Entity_Id); /* The relevant constituents of a subprogram binding to a GCC builtin. Used to pass around calls performing profile compatibility checks. */ typedef struct { Entity_Id gnat_entity; /* The Ada subprogram entity. */ tree ada_fntype; /* The corresponding GCC type node. */ tree btin_fntype; /* The GCC builtin function type node. */ } intrin_binding_t; static bool intrin_profiles_compatible_p (intrin_binding_t *); /* Given GNAT_ENTITY, a GNAT defining identifier node, which denotes some Ada entity, return the equivalent GCC tree for that entity (a ..._DECL node) and associate the ..._DECL node with the input GNAT defining identifier. If GNAT_ENTITY is a variable or a constant declaration, GNU_EXPR gives its initial value (in GCC tree form). This is optional for a variable. For a renamed entity, GNU_EXPR gives the object being renamed. DEFINITION is nonzero if this call is intended for a definition. This is used for separate compilation where it is necessary to know whether an external declaration or a definition must be created if the GCC equivalent was not created previously. The value of 1 is normally used for a nonzero DEFINITION, but a value of 2 is used in special circumstances, defined in the code. */ tree gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, int definition) { /* Contains the kind of the input GNAT node. */ const Entity_Kind kind = Ekind (gnat_entity); /* True if this is a type. */ const bool is_type = IN (kind, Type_Kind); /* True if debug info is requested for this entity. */ const bool debug_info_p = Needs_Debug_Info (gnat_entity); /* True if this entity is to be considered as imported. */ const bool imported_p = (Is_Imported (gnat_entity) && No (Address_Clause (gnat_entity))); /* For a type, contains the equivalent GNAT node to be used in gigi. */ Entity_Id gnat_equiv_type = Empty; /* Temporary used to walk the GNAT tree. */ Entity_Id gnat_temp; /* Contains the GCC DECL node which is equivalent to the input GNAT node. This node will be associated with the GNAT node by calling at the end of the `switch' statement. */ tree gnu_decl = NULL_TREE; /* Contains the GCC type to be used for the GCC node. */ tree gnu_type = NULL_TREE; /* Contains the GCC size tree to be used for the GCC node. */ tree gnu_size = NULL_TREE; /* Contains the GCC name to be used for the GCC node. */ tree gnu_entity_name; /* True if we have already saved gnu_decl as a GNAT association. */ bool saved = false; /* True if we incremented defer_incomplete_level. */ bool this_deferred = false; /* True if we incremented force_global. */ bool this_global = false; /* True if we should check to see if elaborated during processing. */ bool maybe_present = false; /* True if we made GNU_DECL and its type here. */ bool this_made_decl = false; /* Size and alignment of the GCC node, if meaningful. */ unsigned int esize = 0, align = 0; /* Contains the list of attributes directly attached to the entity. */ struct attrib *attr_list = NULL; /* Since a use of an Itype is a definition, process it as such if it is not in a with'ed unit. */ if (!definition && is_type && Is_Itype (gnat_entity) && !present_gnu_tree (gnat_entity) && In_Extended_Main_Code_Unit (gnat_entity)) { /* Ensure that we are in a subprogram mentioned in the Scope chain of this entity, our current scope is global, or we encountered a task or entry (where we can't currently accurately check scoping). */ if (!current_function_decl || DECL_ELABORATION_PROC_P (current_function_decl)) { process_type (gnat_entity); return get_gnu_tree (gnat_entity); } for (gnat_temp = Scope (gnat_entity); Present (gnat_temp); gnat_temp = Scope (gnat_temp)) { if (Is_Type (gnat_temp)) gnat_temp = Underlying_Type (gnat_temp); if (Ekind (gnat_temp) == E_Subprogram_Body) gnat_temp = Corresponding_Spec (Parent (Declaration_Node (gnat_temp))); if (IN (Ekind (gnat_temp), Subprogram_Kind) && Present (Protected_Body_Subprogram (gnat_temp))) gnat_temp = Protected_Body_Subprogram (gnat_temp); if (Ekind (gnat_temp) == E_Entry || Ekind (gnat_temp) == E_Entry_Family || Ekind (gnat_temp) == E_Task_Type || (IN (Ekind (gnat_temp), Subprogram_Kind) && present_gnu_tree (gnat_temp) && (current_function_decl == gnat_to_gnu_entity (gnat_temp, NULL_TREE, 0)))) { process_type (gnat_entity); return get_gnu_tree (gnat_entity); } } /* This abort means the Itype has an incorrect scope, i.e. that its scope does not correspond to the subprogram it is declared in. */ gcc_unreachable (); } /* If we've already processed this entity, return what we got last time. If we are defining the node, we should not have already processed it. In that case, we will abort below when we try to save a new GCC tree for this object. We also need to handle the case of getting a dummy type when a Full_View exists but be careful so as not to trigger its premature elaboration. */ if ((!definition || (is_type && imported_p)) && present_gnu_tree (gnat_entity)) { gnu_decl = get_gnu_tree (gnat_entity); if (TREE_CODE (gnu_decl) == TYPE_DECL && TYPE_IS_DUMMY_P (TREE_TYPE (gnu_decl)) && IN (kind, Incomplete_Or_Private_Kind) && Present (Full_View (gnat_entity)) && (present_gnu_tree (Full_View (gnat_entity)) || No (Freeze_Node (Full_View (gnat_entity))))) { gnu_decl = gnat_to_gnu_entity (Full_View (gnat_entity), NULL_TREE, 0); save_gnu_tree (gnat_entity, NULL_TREE, false); save_gnu_tree (gnat_entity, gnu_decl, false); } return gnu_decl; } /* If this is a numeric or enumeral type, or an access type, a nonzero Esize must be specified unless it was specified by the programmer. Exceptions are for access-to-protected-subprogram types and all access subtypes, as another GNAT type is used to lay out the GCC type for them. */ gcc_assert (!Unknown_Esize (gnat_entity) || Has_Size_Clause (gnat_entity) || (!IN (kind, Numeric_Kind) && !IN (kind, Enumeration_Kind) && (!IN (kind, Access_Kind) || kind == E_Access_Protected_Subprogram_Type || kind == E_Anonymous_Access_Protected_Subprogram_Type || kind == E_Access_Subtype || type_annotate_only))); /* The RM size must be specified for all discrete and fixed-point types. */ gcc_assert (!(IN (kind, Discrete_Or_Fixed_Point_Kind) && Unknown_RM_Size (gnat_entity))); /* If we get here, it means we have not yet done anything with this entity. If we are not defining it, it must be a type or an entity that is defined elsewhere or externally, otherwise we should have defined it already. */ gcc_assert (definition || type_annotate_only || is_type || kind == E_Discriminant || kind == E_Component || kind == E_Label || (kind == E_Constant && Present (Full_View (gnat_entity))) || Is_Public (gnat_entity)); /* Get the name of the entity and set up the line number and filename of the original definition for use in any decl we make. Make sure we do not inherit another source location. */ gnu_entity_name = get_entity_name (gnat_entity); if (Sloc (gnat_entity) != No_Location && !renaming_from_generic_instantiation_p (gnat_entity)) Sloc_to_locus (Sloc (gnat_entity), &input_location); /* For cases when we are not defining (i.e., we are referencing from another compilation unit) public entities, show we are at global level for the purpose of computing scopes. Don't do this for components or discriminants since the relevant test is whether or not the record is being defined. */ if (!definition && kind != E_Component && kind != E_Discriminant && Is_Public (gnat_entity) && !Is_Statically_Allocated (gnat_entity)) force_global++, this_global = true; /* Handle any attributes directly attached to the entity. */ if (Has_Gigi_Rep_Item (gnat_entity)) prepend_attributes (&attr_list, gnat_entity); /* Do some common processing for types. */ if (is_type) { /* Compute the equivalent type to be used in gigi. */ gnat_equiv_type = Gigi_Equivalent_Type (gnat_entity); /* Machine_Attributes on types are expected to be propagated to subtypes. The corresponding Gigi_Rep_Items are only attached to the first subtype though, so we handle the propagation here. */ if (Base_Type (gnat_entity) != gnat_entity && !Is_First_Subtype (gnat_entity) && Has_Gigi_Rep_Item (First_Subtype (Base_Type (gnat_entity)))) prepend_attributes (&attr_list, First_Subtype (Base_Type (gnat_entity))); /* Compute a default value for the size of an elementary type. */ if (Known_Esize (gnat_entity) && Is_Elementary_Type (gnat_entity)) { unsigned int max_esize; gcc_assert (UI_Is_In_Int_Range (Esize (gnat_entity))); esize = UI_To_Int (Esize (gnat_entity)); if (IN (kind, Float_Kind)) max_esize = fp_prec_to_size (LONG_DOUBLE_TYPE_SIZE); else if (IN (kind, Access_Kind)) max_esize = POINTER_SIZE * 2; else max_esize = LONG_LONG_TYPE_SIZE; if (esize > max_esize) esize = max_esize; } } switch (kind) { case E_Component: case E_Discriminant: { /* The GNAT record where the component was defined. */ Entity_Id gnat_record = Underlying_Type (Scope (gnat_entity)); /* If the entity is a discriminant of an extended tagged type used to rename a discriminant of the parent type, return the latter. */ if (Is_Tagged_Type (gnat_record) && Present (Corresponding_Discriminant (gnat_entity))) { gnu_decl = gnat_to_gnu_entity (Corresponding_Discriminant (gnat_entity), gnu_expr, definition); saved = true; break; } /* If the entity is an inherited component (in the case of extended tagged record types), just return the original entity, which must be a FIELD_DECL. Likewise for discriminants. If the entity is a non-girder discriminant (in the case of derived untagged record types), return the stored discriminant it renames. */ else if (Present (Original_Record_Component (gnat_entity)) && Original_Record_Component (gnat_entity) != gnat_entity) { gnu_decl = gnat_to_gnu_entity (Original_Record_Component (gnat_entity), gnu_expr, definition); saved = true; break; } /* Otherwise, if we are not defining this and we have no GCC type for the containing record, make one for it. Then we should have made our own equivalent. */ else if (!definition && !present_gnu_tree (gnat_record)) { /* ??? If this is in a record whose scope is a protected type and we have an Original_Record_Component, use it. This is a workaround for major problems in protected type handling. */ Entity_Id Scop = Scope (Scope (gnat_entity)); if (Is_Protected_Type (Underlying_Type (Scop)) && Present (Original_Record_Component (gnat_entity))) { gnu_decl = gnat_to_gnu_entity (Original_Record_Component (gnat_entity), gnu_expr, 0); saved = true; break; } gnat_to_gnu_entity (Scope (gnat_entity), NULL_TREE, 0); gnu_decl = get_gnu_tree (gnat_entity); saved = true; break; } else /* Here we have no GCC type and this is a reference rather than a definition. This should never happen. Most likely the cause is reference before declaration in the GNAT tree for gnat_entity. */ gcc_unreachable (); } case E_Constant: /* Ignore constant definitions already marked with the error node. See the N_Object_Declaration case of gnat_to_gnu for the rationale. */ if (definition && gnu_expr && present_gnu_tree (gnat_entity) && get_gnu_tree (gnat_entity) == error_mark_node) { maybe_present = true; break; } /* Ignore deferred constant definitions without address clause since they are processed fully in the front-end. If No_Initialization is set, this is not a deferred constant but a constant whose value is built manually. And constants that are renamings are handled like variables. */ if (definition && !gnu_expr && No (Address_Clause (gnat_entity)) && !No_Initialization (Declaration_Node (gnat_entity)) && No (Renamed_Object (gnat_entity))) { gnu_decl = error_mark_node; saved = true; break; } /* If this is a use of a deferred constant without address clause, get its full definition. */ if (!definition && No (Address_Clause (gnat_entity)) && Present (Full_View (gnat_entity))) { gnu_decl = gnat_to_gnu_entity (Full_View (gnat_entity), gnu_expr, 0); saved = true; break; } /* If we have a constant that we are not defining, get the expression it was defined to represent. This is necessary to avoid generating dumb elaboration code in simple cases, but we may throw it away later if it is not a constant. But do not retrieve it if it is an allocator since the designated type might still be dummy at this point. */ if (!definition && !No_Initialization (Declaration_Node (gnat_entity)) && Present (Expression (Declaration_Node (gnat_entity))) && Nkind (Expression (Declaration_Node (gnat_entity))) != N_Allocator) { bool went_into_elab_proc = false; int save_force_global = force_global; /* The expression may contain N_Expression_With_Actions nodes and thus object declarations from other units. In this case, even though the expression will eventually be discarded since not a constant, the declarations would be stuck either in the global varpool or in the current scope. Therefore we force the local context and create a fake scope that we'll zap at the end. */ if (!current_function_decl) { current_function_decl = get_elaboration_procedure (); went_into_elab_proc = true; } force_global = 0; gnat_pushlevel (); gnu_expr = gnat_to_gnu (Expression (Declaration_Node (gnat_entity))); gnat_zaplevel (); force_global = save_force_global; if (went_into_elab_proc) current_function_decl = NULL_TREE; } /* ... fall through ... */ case E_Exception: case E_Loop_Parameter: case E_Out_Parameter: case E_Variable: { /* Always create a variable for volatile objects and variables seen constant but with a Linker_Section pragma. */ bool const_flag = ((kind == E_Constant || kind == E_Variable) && Is_True_Constant (gnat_entity) && !(kind == E_Variable && Present (Linker_Section_Pragma (gnat_entity))) && !Treat_As_Volatile (gnat_entity) && (((Nkind (Declaration_Node (gnat_entity)) == N_Object_Declaration) && Present (Expression (Declaration_Node (gnat_entity)))) || Present (Renamed_Object (gnat_entity)) || imported_p)); bool inner_const_flag = const_flag; bool static_p = Is_Statically_Allocated (gnat_entity); bool mutable_p = false; bool used_by_ref = false; tree gnu_ext_name = NULL_TREE; tree renamed_obj = NULL_TREE; tree gnu_object_size; if (Present (Renamed_Object (gnat_entity)) && !definition) { if (kind == E_Exception) gnu_expr = gnat_to_gnu_entity (Renamed_Entity (gnat_entity), NULL_TREE, 0); else gnu_expr = gnat_to_gnu (Renamed_Object (gnat_entity)); } /* Get the type after elaborating the renamed object. */ gnu_type = gnat_to_gnu_type (Etype (gnat_entity)); /* If this is a standard exception definition, then use the standard exception type. This is necessary to make sure that imported and exported views of exceptions are properly merged in LTO mode. */ if (TREE_CODE (TYPE_NAME (gnu_type)) == TYPE_DECL && DECL_NAME (TYPE_NAME (gnu_type)) == exception_data_name_id) gnu_type = except_type_node; /* For a debug renaming declaration, build a debug-only entity. */ if (Present (Debug_Renaming_Link (gnat_entity))) { /* Force a non-null value to make sure the symbol is retained. */ tree value = build1 (INDIRECT_REF, gnu_type, build1 (NOP_EXPR, build_pointer_type (gnu_type), integer_minus_one_node)); gnu_decl = build_decl (input_location, VAR_DECL, gnu_entity_name, gnu_type); SET_DECL_VALUE_EXPR (gnu_decl, value); DECL_HAS_VALUE_EXPR_P (gnu_decl) = 1; gnat_pushdecl (gnu_decl, gnat_entity); break; } /* If this is a loop variable, its type should be the base type. This is because the code for processing a loop determines whether a normal loop end test can be done by comparing the bounds of the loop against those of the base type, which is presumed to be the size used for computation. But this is not correct when the size of the subtype is smaller than the type. */ if (kind == E_Loop_Parameter) gnu_type = get_base_type (gnu_type); /* Reject non-renamed objects whose type is an unconstrained array or any object whose type is a dummy type or void. */ if ((TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE && No (Renamed_Object (gnat_entity))) || TYPE_IS_DUMMY_P (gnu_type) || TREE_CODE (gnu_type) == VOID_TYPE) { gcc_assert (type_annotate_only); if (this_global) force_global--; return error_mark_node; } /* If an alignment is specified, use it if valid. Note that exceptions are objects but don't have an alignment. We must do this before we validate the size, since the alignment can affect the size. */ if (kind != E_Exception && Known_Alignment (gnat_entity)) { gcc_assert (Present (Alignment (gnat_entity))); align = validate_alignment (Alignment (gnat_entity), gnat_entity, TYPE_ALIGN (gnu_type)); /* No point in changing the type if there is an address clause as the final type of the object will be a reference type. */ if (Present (Address_Clause (gnat_entity))) align = 0; else { tree orig_type = gnu_type; gnu_type = maybe_pad_type (gnu_type, NULL_TREE, align, gnat_entity, false, false, definition, true); /* If a padding record was made, declare it now since it will never be declared otherwise. This is necessary to ensure that its subtrees are properly marked. */ if (gnu_type != orig_type && !DECL_P (TYPE_NAME (gnu_type))) create_type_decl (TYPE_NAME (gnu_type), gnu_type, true, debug_info_p, gnat_entity); } } /* If we are defining the object, see if it has a Size and validate it if so. If we are not defining the object and a Size clause applies, simply retrieve the value. We don't want to ignore the clause and it is expected to have been validated already. Then get the new type, if any. */ if (definition) gnu_size = validate_size (Esize (gnat_entity), gnu_type, gnat_entity, VAR_DECL, false, Has_Size_Clause (gnat_entity)); else if (Has_Size_Clause (gnat_entity)) gnu_size = UI_To_gnu (Esize (gnat_entity), bitsizetype); if (gnu_size) { gnu_type = make_type_from_size (gnu_type, gnu_size, Has_Biased_Representation (gnat_entity)); if (operand_equal_p (TYPE_SIZE (gnu_type), gnu_size, 0)) gnu_size = NULL_TREE; } /* If this object has self-referential size, it must be a record with a default discriminant. We are supposed to allocate an object of the maximum size in this case, unless it is a constant with an initializing expression, in which case we can get the size from that. Note that the resulting size may still be a variable, so this may end up with an indirect allocation. */ if (No (Renamed_Object (gnat_entity)) && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))) { if (gnu_expr && kind == E_Constant) { tree size = TYPE_SIZE (TREE_TYPE (gnu_expr)); if (CONTAINS_PLACEHOLDER_P (size)) { /* If the initializing expression is itself a constant, despite having a nominal type with self-referential size, we can get the size directly from it. */ if (TREE_CODE (gnu_expr) == COMPONENT_REF && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_expr, 0))) && TREE_CODE (TREE_OPERAND (gnu_expr, 0)) == VAR_DECL && (TREE_READONLY (TREE_OPERAND (gnu_expr, 0)) || DECL_READONLY_ONCE_ELAB (TREE_OPERAND (gnu_expr, 0)))) gnu_size = DECL_SIZE (TREE_OPERAND (gnu_expr, 0)); else gnu_size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, gnu_expr); } else gnu_size = size; } /* We may have no GNU_EXPR because No_Initialization is set even though there's an Expression. */ else if (kind == E_Constant && (Nkind (Declaration_Node (gnat_entity)) == N_Object_Declaration) && Present (Expression (Declaration_Node (gnat_entity)))) gnu_size = TYPE_SIZE (gnat_to_gnu_type (Etype (Expression (Declaration_Node (gnat_entity))))); else { gnu_size = max_size (TYPE_SIZE (gnu_type), true); mutable_p = true; } /* If we are at global level and the size isn't constant, call elaborate_expression_1 to make a variable for it rather than calculating it each time. */ if (global_bindings_p () && !TREE_CONSTANT (gnu_size)) gnu_size = elaborate_expression_1 (gnu_size, gnat_entity, "SIZE", definition, false); } /* If the size is zero byte, make it one byte since some linkers have troubles with zero-sized objects. If the object will have a template, that will make it nonzero so don't bother. Also avoid doing that for an object renaming or an object with an address clause, as we would lose useful information on the view size (e.g. for null array slices) and we are not allocating the object here anyway. */ if (((gnu_size && integer_zerop (gnu_size) && !TREE_OVERFLOW (gnu_size)) || (TYPE_SIZE (gnu_type) && integer_zerop (TYPE_SIZE (gnu_type)) && !TREE_OVERFLOW (TYPE_SIZE (gnu_type)))) && !Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity)) && No (Renamed_Object (gnat_entity)) && No (Address_Clause (gnat_entity))) gnu_size = bitsize_unit_node; /* If this is an object with no specified size and alignment, and if either it is atomic or we are not optimizing alignment for space and it is composite and not an exception, an Out parameter or a reference to another object, and the size of its type is a constant, set the alignment to the smallest one which is not smaller than the size, with an appropriate cap. */ if (!gnu_size && align == 0 && (Is_Atomic_Or_VFA (gnat_entity) || (!Optimize_Alignment_Space (gnat_entity) && kind != E_Exception && kind != E_Out_Parameter && Is_Composite_Type (Etype (gnat_entity)) && !Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity)) && !Is_Exported (gnat_entity) && !imported_p && No (Renamed_Object (gnat_entity)) && No (Address_Clause (gnat_entity)))) && TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST) { unsigned int size_cap, align_cap; /* No point in promoting the alignment if this doesn't prevent BLKmode access to the object, in particular block copy, as this will for example disable the NRV optimization for it. No point in jumping through all the hoops needed in order to support BIGGEST_ALIGNMENT if we don't really have to. So we cap to the smallest alignment that corresponds to a known efficient memory access pattern of the target. */ if (Is_Atomic_Or_VFA (gnat_entity)) { size_cap = UINT_MAX; align_cap = BIGGEST_ALIGNMENT; } else { size_cap = MAX_FIXED_MODE_SIZE; align_cap = get_mode_alignment (ptr_mode); } if (!tree_fits_uhwi_p (TYPE_SIZE (gnu_type)) || compare_tree_int (TYPE_SIZE (gnu_type), size_cap) > 0) align = 0; else if (compare_tree_int (TYPE_SIZE (gnu_type), align_cap) > 0) align = align_cap; else align = ceil_pow2 (tree_to_uhwi (TYPE_SIZE (gnu_type))); /* But make sure not to under-align the object. */ if (align <= TYPE_ALIGN (gnu_type)) align = 0; /* And honor the minimum valid atomic alignment, if any. */ #ifdef MINIMUM_ATOMIC_ALIGNMENT else if (align < MINIMUM_ATOMIC_ALIGNMENT) align = MINIMUM_ATOMIC_ALIGNMENT; #endif } /* If the object is set to have atomic components, find the component type and validate it. ??? Note that we ignore Has_Volatile_Components on objects; it's not at all clear what to do in that case. */ if (Has_Atomic_Components (gnat_entity)) { tree gnu_inner = (TREE_CODE (gnu_type) == ARRAY_TYPE ? TREE_TYPE (gnu_type) : gnu_type); while (TREE_CODE (gnu_inner) == ARRAY_TYPE && TYPE_MULTI_ARRAY_P (gnu_inner)) gnu_inner = TREE_TYPE (gnu_inner); check_ok_for_atomic_type (gnu_inner, gnat_entity, true); } /* If this is an aliased object with an unconstrained array nominal subtype, make a type that includes the template. We will either allocate or create a variable of that type, see below. */ if (Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity)) && Is_Array_Type (Underlying_Type (Etype (gnat_entity))) && !type_annotate_only) { tree gnu_array = gnat_to_gnu_type (Base_Type (Etype (gnat_entity))); gnu_type = build_unc_object_type_from_ptr (TREE_TYPE (gnu_array), gnu_type, concat_name (gnu_entity_name, "UNC"), debug_info_p); } /* ??? If this is an object of CW type initialized to a value, try to ensure that the object is sufficient aligned for this value, but without pessimizing the allocation. This is a kludge necessary because we don't support dynamic alignment. */ if (align == 0 && Ekind (Etype (gnat_entity)) == E_Class_Wide_Subtype && No (Renamed_Object (gnat_entity)) && No (Address_Clause (gnat_entity))) align = get_target_system_allocator_alignment () * BITS_PER_UNIT; #ifdef MINIMUM_ATOMIC_ALIGNMENT /* If the size is a constant and no alignment is specified, force the alignment to be the minimum valid atomic alignment. The restriction on constant size avoids problems with variable-size temporaries; if the size is variable, there's no issue with atomic access. Also don't do this for a constant, since it isn't necessary and can interfere with constant replacement. Finally, do not do it for Out parameters since that creates an size inconsistency with In parameters. */ if (align == 0 && MINIMUM_ATOMIC_ALIGNMENT > TYPE_ALIGN (gnu_type) && !FLOAT_TYPE_P (gnu_type) && !const_flag && No (Renamed_Object (gnat_entity)) && !imported_p && No (Address_Clause (gnat_entity)) && kind != E_Out_Parameter && (gnu_size ? TREE_CODE (gnu_size) == INTEGER_CST : TREE_CODE (TYPE_SIZE (gnu_type)) == INTEGER_CST)) align = MINIMUM_ATOMIC_ALIGNMENT; #endif /* Make a new type with the desired size and alignment, if needed. But do not take into account alignment promotions to compute the size of the object. */ gnu_object_size = gnu_size ? gnu_size : TYPE_SIZE (gnu_type); if (gnu_size || align > 0) { tree orig_type = gnu_type; gnu_type = maybe_pad_type (gnu_type, gnu_size, align, gnat_entity, false, false, definition, true); /* If a padding record was made, declare it now since it will never be declared otherwise. This is necessary to ensure that its subtrees are properly marked. */ if (gnu_type != orig_type && !DECL_P (TYPE_NAME (gnu_type))) create_type_decl (TYPE_NAME (gnu_type), gnu_type, true, debug_info_p, gnat_entity); } /* Now check if the type of the object allows atomic access. */ if (Is_Atomic_Or_VFA (gnat_entity)) check_ok_for_atomic_type (gnu_type, gnat_entity, false); /* If this is a renaming, avoid as much as possible to create a new object. However, in some cases, creating it is required because renaming can be applied to objects that are not names in Ada. This processing needs to be applied to the raw expression so as to make it more likely to rename the underlying object. */ if (Present (Renamed_Object (gnat_entity))) { /* If the renamed object had padding, strip off the reference to the inner object and reset our type. */ if ((TREE_CODE (gnu_expr) == COMPONENT_REF && TYPE_IS_PADDING_P (TREE_TYPE (TREE_OPERAND (gnu_expr, 0)))) /* Strip useless conversions around the object. */ || gnat_useless_type_conversion (gnu_expr)) { gnu_expr = TREE_OPERAND (gnu_expr, 0); gnu_type = TREE_TYPE (gnu_expr); } /* Or else, if the renamed object has an unconstrained type with default discriminant, use the padded type. */ else if (type_is_padding_self_referential (TREE_TYPE (gnu_expr))) gnu_type = TREE_TYPE (gnu_expr); /* Case 1: if this is a constant renaming stemming from a function call, treat it as a normal object whose initial value is what is being renamed. RM 3.3 says that the result of evaluating a function call is a constant object. Therefore, it can be the inner object of a constant renaming and the renaming must be fully instantiated, i.e. it cannot be a reference to (part of) an existing object. And treat null expressions, constructors and literals the same way. */ tree inner = gnu_expr; while (handled_component_p (inner) || CONVERT_EXPR_P (inner)) inner = TREE_OPERAND (inner, 0); /* Expand_Dispatching_Call can prepend a comparison of the tags before the call to "=". */ if (TREE_CODE (inner) == TRUTH_ANDIF_EXPR) inner = TREE_OPERAND (inner, 1); if ((TREE_CODE (inner) == CALL_EXPR && !call_is_atomic_load (inner)) || TREE_CODE (inner) == NULL_EXPR || TREE_CODE (inner) == CONSTRUCTOR || CONSTANT_CLASS_P (inner)) ; /* Case 2: if the renaming entity need not be materialized, use the elaborated renamed expression for the renaming. But this means that the caller is responsible for evaluating the address of the renaming in the correct place for the definition case to instantiate the SAVE_EXPRs. */ else if (TREE_CODE (inner) != COMPOUND_EXPR && !Materialize_Entity (gnat_entity)) { tree init = NULL_TREE; gnu_decl = elaborate_reference (gnu_expr, gnat_entity, definition, &init); /* We cannot evaluate the first arm of a COMPOUND_EXPR in the correct place for this case, hence the above test. */ gcc_assert (init == NULL_TREE); /* No DECL_EXPR will be created so the expression needs to be marked manually because it will likely be shared. */ if (global_bindings_p ()) MARK_VISITED (gnu_decl); /* This assertion will fail if the renamed object isn't aligned enough as to make it possible to honor the alignment set on the renaming. */ if (align) { unsigned int ralign = DECL_P (gnu_decl) ? DECL_ALIGN (gnu_decl) : TYPE_ALIGN (TREE_TYPE (gnu_decl)); gcc_assert (ralign >= align); } save_gnu_tree (gnat_entity, gnu_decl, true); saved = true; annotate_object (gnat_entity, gnu_type, NULL_TREE, false); break; } /* Case 3: otherwise, make a constant pointer to the object we are renaming and attach the object to the pointer after it is elaborated. The object will be referenced directly instead of indirectly via the pointer to avoid aliasing problems with non-addressable entities. The pointer is called a "renaming" pointer in this case. Note that we also need to preserve the volatility of the renamed object through the indirection. */ else { tree init = NULL_TREE; if (TREE_THIS_VOLATILE (gnu_expr) && !TYPE_VOLATILE (gnu_type)) gnu_type = change_qualified_type (gnu_type, TYPE_QUAL_VOLATILE); gnu_type = build_reference_type (gnu_type); used_by_ref = true; const_flag = true; inner_const_flag = TREE_READONLY (gnu_expr); gnu_size = NULL_TREE; renamed_obj = elaborate_reference (gnu_expr, gnat_entity, definition, &init); /* If we are not defining the entity, the expression will not be attached through DECL_INITIAL so it needs to be marked manually because it will likely be shared. Likewise for a dereference as it will be folded by the ADDR_EXPR below. */ if ((!definition || TREE_CODE (renamed_obj) == INDIRECT_REF) && global_bindings_p ()) MARK_VISITED (renamed_obj); if (type_annotate_only && TREE_CODE (renamed_obj) == ERROR_MARK) gnu_expr = NULL_TREE; else { gnu_expr = build_unary_op (ADDR_EXPR, gnu_type, renamed_obj); if (init) gnu_expr = build_compound_expr (TREE_TYPE (gnu_expr), init, gnu_expr); } } } /* Make a volatile version of this object's type if we are to make the object volatile. We also interpret 13.3(19) conservatively and disallow any optimizations for such a non-constant object. */ if ((Treat_As_Volatile (gnat_entity) || (!const_flag && gnu_type != except_type_node && (Is_Exported (gnat_entity) || imported_p || Present (Address_Clause (gnat_entity))))) && !TYPE_VOLATILE (gnu_type)) { const int quals = TYPE_QUAL_VOLATILE | (Is_Atomic_Or_VFA (gnat_entity) ? TYPE_QUAL_ATOMIC : 0); gnu_type = change_qualified_type (gnu_type, quals); } /* If we are defining an aliased object whose nominal subtype is unconstrained, the object is a record that contains both the template and the object. If there is an initializer, it will have already been converted to the right type, but we need to create the template if there is no initializer. */ if (definition && !gnu_expr && TREE_CODE (gnu_type) == RECORD_TYPE && (TYPE_CONTAINS_TEMPLATE_P (gnu_type) /* Beware that padding might have been introduced above. */ || (TYPE_PADDING_P (gnu_type) && TREE_CODE (TREE_TYPE (TYPE_FIELDS (gnu_type))) == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (TREE_TYPE (TYPE_FIELDS (gnu_type)))))) { tree template_field = TYPE_PADDING_P (gnu_type) ? TYPE_FIELDS (TREE_TYPE (TYPE_FIELDS (gnu_type))) : TYPE_FIELDS (gnu_type); vec *v; vec_alloc (v, 1); tree t = build_template (TREE_TYPE (template_field), TREE_TYPE (DECL_CHAIN (template_field)), NULL_TREE); CONSTRUCTOR_APPEND_ELT (v, template_field, t); gnu_expr = gnat_build_constructor (gnu_type, v); } /* Convert the expression to the type of the object if need be. */ if (gnu_expr && initial_value_needs_conversion (gnu_type, gnu_expr)) gnu_expr = convert (gnu_type, gnu_expr); /* If this is a pointer that doesn't have an initializing expression, initialize it to NULL, unless the object is imported. */ if (definition && (POINTER_TYPE_P (gnu_type) || TYPE_IS_FAT_POINTER_P (gnu_type)) && !gnu_expr && !Is_Imported (gnat_entity)) gnu_expr = integer_zero_node; /* If we are defining the object and it has an Address clause, we must either get the address expression from the saved GCC tree for the object if it has a Freeze node, or elaborate the address expression here since the front-end has guaranteed that the elaboration has no effects in this case. */ if (definition && Present (Address_Clause (gnat_entity))) { const Node_Id gnat_clause = Address_Clause (gnat_entity); Node_Id gnat_expr = Expression (gnat_clause); tree gnu_address = present_gnu_tree (gnat_entity) ? get_gnu_tree (gnat_entity) : gnat_to_gnu (gnat_expr); save_gnu_tree (gnat_entity, NULL_TREE, false); /* Convert the type of the object to a reference type that can alias everything as per 13.3(19). */ gnu_type = build_reference_type_for_mode (gnu_type, ptr_mode, true); gnu_address = convert (gnu_type, gnu_address); used_by_ref = true; const_flag = !Is_Public (gnat_entity) || compile_time_known_address_p (gnat_expr); gnu_size = NULL_TREE; /* If this is an aliased object with an unconstrained array nominal subtype, then it can overlay only another aliased object with an unconstrained array nominal subtype and compatible template. */ if (Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity)) && Is_Array_Type (Underlying_Type (Etype (gnat_entity))) && !type_annotate_only) { tree rec_type = TREE_TYPE (gnu_type); tree off = byte_position (DECL_CHAIN (TYPE_FIELDS (rec_type))); /* This is the pattern built for a regular object. */ if (TREE_CODE (gnu_address) == POINTER_PLUS_EXPR && TREE_OPERAND (gnu_address, 1) == off) gnu_address = TREE_OPERAND (gnu_address, 0); /* This is the pattern built for an overaligned object. */ else if (TREE_CODE (gnu_address) == POINTER_PLUS_EXPR && TREE_CODE (TREE_OPERAND (gnu_address, 1)) == PLUS_EXPR && TREE_OPERAND (TREE_OPERAND (gnu_address, 1), 1) == off) gnu_address = build2 (POINTER_PLUS_EXPR, gnu_type, TREE_OPERAND (gnu_address, 0), TREE_OPERAND (TREE_OPERAND (gnu_address, 1), 0)); else { post_error_ne ("aliased object& with unconstrained array " "nominal subtype", gnat_clause, gnat_entity); post_error ("\\can overlay only aliased object with " "compatible subtype", gnat_clause); } } /* If this is a deferred constant, the initializer is attached to the full view. */ if (kind == E_Constant && Present (Full_View (gnat_entity))) gnu_expr = gnat_to_gnu (Expression (Declaration_Node (Full_View (gnat_entity)))); /* If we don't have an initializing expression for the underlying variable, the initializing expression for the pointer is the specified address. Otherwise, we have to make a COMPOUND_EXPR to assign both the address and the initial value. */ if (!gnu_expr) gnu_expr = gnu_address; else gnu_expr = build2 (COMPOUND_EXPR, gnu_type, build_binary_op (INIT_EXPR, NULL_TREE, build_unary_op (INDIRECT_REF, NULL_TREE, gnu_address), gnu_expr), gnu_address); } /* If it has an address clause and we are not defining it, mark it as an indirect object. Likewise for Stdcall objects that are imported. */ if ((!definition && Present (Address_Clause (gnat_entity))) || (Is_Imported (gnat_entity) && Has_Stdcall_Convention (gnat_entity))) { /* Convert the type of the object to a reference type that can alias everything as per 13.3(19). */ gnu_type = build_reference_type_for_mode (gnu_type, ptr_mode, true); used_by_ref = true; gnu_size = NULL_TREE; /* No point in taking the address of an initializing expression that isn't going to be used. */ gnu_expr = NULL_TREE; /* If it has an address clause whose value is known at compile time, make the object a CONST_DECL. This will avoid a useless dereference. */ if (Present (Address_Clause (gnat_entity))) { Node_Id gnat_address = Expression (Address_Clause (gnat_entity)); if (compile_time_known_address_p (gnat_address)) { gnu_expr = gnat_to_gnu (gnat_address); const_flag = true; } } } /* If we are at top level and this object is of variable size, make the actual type a hidden pointer to the real type and make the initializer be a memory allocation and initialization. Likewise for objects we aren't defining (presumed to be external references from other packages), but there we do not set up an initialization. If the object's size overflows, make an allocator too, so that Storage_Error gets raised. Note that we will never free such memory, so we presume it never will get allocated. */ if (!allocatable_size_p (TYPE_SIZE_UNIT (gnu_type), global_bindings_p () || !definition || static_p) || (gnu_size && !allocatable_size_p (convert (sizetype, size_binop (CEIL_DIV_EXPR, gnu_size, bitsize_unit_node)), global_bindings_p () || !definition || static_p))) { gnu_type = build_reference_type (gnu_type); used_by_ref = true; const_flag = true; gnu_size = NULL_TREE; /* In case this was a aliased object whose nominal subtype is unconstrained, the pointer above will be a thin pointer and build_allocator will automatically make the template. If we have a template initializer only (that we made above), pretend there is none and rely on what build_allocator creates again anyway. Otherwise (if we have a full initializer), get the data part and feed that to build_allocator. If we are elaborating a mutable object, tell build_allocator to ignore a possibly simpler size from the initializer, if any, as we must allocate the maximum possible size in this case. */ if (definition && !imported_p) { tree gnu_alloc_type = TREE_TYPE (gnu_type); if (TREE_CODE (gnu_alloc_type) == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (gnu_alloc_type)) { gnu_alloc_type = TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (gnu_alloc_type))); if (TREE_CODE (gnu_expr) == CONSTRUCTOR && vec_safe_length (CONSTRUCTOR_ELTS (gnu_expr)) == 1) gnu_expr = NULL_TREE; else gnu_expr = build_component_ref (gnu_expr, NULL_TREE, DECL_CHAIN (TYPE_FIELDS (TREE_TYPE (gnu_expr))), false); } if (TREE_CODE (TYPE_SIZE_UNIT (gnu_alloc_type)) == INTEGER_CST && !valid_constant_size_p (TYPE_SIZE_UNIT (gnu_alloc_type))) post_error ("?`Storage_Error` will be raised at run time!", gnat_entity); gnu_expr = build_allocator (gnu_alloc_type, gnu_expr, gnu_type, Empty, Empty, gnat_entity, mutable_p); } else gnu_expr = NULL_TREE; } /* If this object would go into the stack and has an alignment larger than the largest stack alignment the back-end can honor, resort to a variable of "aligning type". */ if (definition && !global_bindings_p () && !static_p && !imported_p && TYPE_ALIGN (gnu_type) > BIGGEST_ALIGNMENT) { /* Create the new variable. No need for extra room before the aligned field as this is in automatic storage. */ tree gnu_new_type = make_aligning_type (gnu_type, TYPE_ALIGN (gnu_type), TYPE_SIZE_UNIT (gnu_type), BIGGEST_ALIGNMENT, 0, gnat_entity); tree gnu_new_var = create_var_decl (create_concat_name (gnat_entity, "ALIGN"), NULL_TREE, gnu_new_type, NULL_TREE, false, false, false, false, NULL, gnat_entity); DECL_ARTIFICIAL (gnu_new_var) = 1; /* Initialize the aligned field if we have an initializer. */ if (gnu_expr) add_stmt_with_node (build_binary_op (INIT_EXPR, NULL_TREE, build_component_ref (gnu_new_var, NULL_TREE, TYPE_FIELDS (gnu_new_type), false), gnu_expr), gnat_entity); /* And setup this entity as a reference to the aligned field. */ gnu_type = build_reference_type (gnu_type); gnu_expr = build_unary_op (ADDR_EXPR, NULL_TREE, build_component_ref (gnu_new_var, NULL_TREE, TYPE_FIELDS (gnu_new_type), false)); TREE_CONSTANT (gnu_expr) = 1; used_by_ref = true; const_flag = true; gnu_size = NULL_TREE; } /* If this is an aliased object with an unconstrained array nominal subtype, we make its type a thin reference, i.e. the reference counterpart of a thin pointer, so it points to the array part. This is aimed to make it easier for the debugger to decode the object. Note that we have to do it this late because of the couple of allocation adjustments that might be made above. */ if (Is_Constr_Subt_For_UN_Aliased (Etype (gnat_entity)) && Is_Array_Type (Underlying_Type (Etype (gnat_entity))) && !type_annotate_only) { /* In case the object with the template has already been allocated just above, we have nothing to do here. */ if (!TYPE_IS_THIN_POINTER_P (gnu_type)) { tree gnu_unc_var = create_var_decl (concat_name (gnu_entity_name, "UNC"), NULL_TREE, gnu_type, gnu_expr, const_flag, Is_Public (gnat_entity), imported_p || !definition, static_p, NULL, gnat_entity); gnu_expr = build_unary_op (ADDR_EXPR, NULL_TREE, gnu_unc_var); TREE_CONSTANT (gnu_expr) = 1; used_by_ref = true; const_flag = true; inner_const_flag = TREE_READONLY (gnu_unc_var); gnu_size = NULL_TREE; } tree gnu_array = gnat_to_gnu_type (Base_Type (Etype (gnat_entity))); gnu_type = build_reference_type (TYPE_OBJECT_RECORD_TYPE (gnu_array)); } if (const_flag) gnu_type = change_qualified_type (gnu_type, TYPE_QUAL_CONST); /* Convert the expression to the type of the object if need be. */ if (gnu_expr && initial_value_needs_conversion (gnu_type, gnu_expr)) gnu_expr = convert (gnu_type, gnu_expr); /* If this name is external or a name was specified, use it, but don't use the Interface_Name with an address clause (see cd30005). */ if ((Present (Interface_Name (gnat_entity)) && No (Address_Clause (gnat_entity))) || (Is_Public (gnat_entity) && (!Is_Imported (gnat_entity) || Is_Exported (gnat_entity)))) gnu_ext_name = create_concat_name (gnat_entity, NULL); /* If this is an aggregate constant initialized to a constant, force it to be statically allocated. This saves an initialization copy. */ if (!static_p && const_flag && gnu_expr && TREE_CONSTANT (gnu_expr) && AGGREGATE_TYPE_P (gnu_type) && tree_fits_uhwi_p (TYPE_SIZE_UNIT (gnu_type)) && !(TYPE_IS_PADDING_P (gnu_type) && !tree_fits_uhwi_p (TYPE_SIZE_UNIT (TREE_TYPE (TYPE_FIELDS (gnu_type)))))) static_p = true; /* Deal with a pragma Linker_Section on a constant or variable. */ if ((kind == E_Constant || kind == E_Variable) && Present (Linker_Section_Pragma (gnat_entity))) prepend_one_attribute_pragma (&attr_list, Linker_Section_Pragma (gnat_entity)); /* Now create the variable or the constant and set various flags. */ gnu_decl = create_var_decl_1 (gnu_entity_name, gnu_ext_name, gnu_type, gnu_expr, const_flag, Is_Public (gnat_entity), imported_p || !definition, static_p, !renamed_obj, attr_list, gnat_entity); DECL_BY_REF_P (gnu_decl) = used_by_ref; DECL_POINTS_TO_READONLY_P (gnu_decl) = used_by_ref && inner_const_flag; DECL_CAN_NEVER_BE_NULL_P (gnu_decl) = Can_Never_Be_Null (gnat_entity); /* If we are defining an Out parameter and optimization isn't enabled, create a fake PARM_DECL for debugging purposes and make it point to the VAR_DECL. Suppress debug info for the latter but make sure it will live in memory so that it can be accessed from within the debugger through the PARM_DECL. */ if (kind == E_Out_Parameter && definition && debug_info_p && !optimize && !flag_generate_lto) { tree param = create_param_decl (gnu_entity_name, gnu_type, false); gnat_pushdecl (param, gnat_entity); SET_DECL_VALUE_EXPR (param, gnu_decl); DECL_HAS_VALUE_EXPR_P (param) = 1; DECL_IGNORED_P (gnu_decl) = 1; TREE_ADDRESSABLE (gnu_decl) = 1; } /* If this is a loop parameter, set the corresponding flag. */ else if (kind == E_Loop_Parameter) DECL_LOOP_PARM_P (gnu_decl) = 1; /* If this is a renaming pointer, attach the renamed object to it. */ if (renamed_obj) SET_DECL_RENAMED_OBJECT (gnu_decl, renamed_obj); /* If this is a constant and we are defining it or it generates a real symbol at the object level and we are referencing it, we may want or need to have a true variable to represent it: - if optimization isn't enabled, for debugging purposes, - if the constant is public and not overlaid on something else, - if its address is taken, - if either itself or its type is aliased. */ if (TREE_CODE (gnu_decl) == CONST_DECL && (definition || Sloc (gnat_entity) > Standard_Location) && ((!optimize && debug_info_p) || (Is_Public (gnat_entity) && No (Address_Clause (gnat_entity))) || Address_Taken (gnat_entity) || Is_Aliased (gnat_entity) || Is_Aliased (Etype (gnat_entity)))) { tree gnu_corr_var = create_true_var_decl (gnu_entity_name, gnu_ext_name, gnu_type, gnu_expr, true, Is_Public (gnat_entity), !definition, static_p, attr_list, gnat_entity); SET_DECL_CONST_CORRESPONDING_VAR (gnu_decl, gnu_corr_var); /* As debugging information will be generated for the variable, do not generate debugging information for the constant. */ if (debug_info_p) DECL_IGNORED_P (gnu_decl) = 1; else DECL_IGNORED_P (gnu_corr_var) = 1; } /* If this is a constant, even if we don't need a true variable, we may need to avoid returning the initializer in every case. That can happen for the address of a (constant) constructor because, upon dereferencing it, the constructor will be reinjected in the tree, which may not be valid in every case; see lvalue_required_p for more details. */ if (TREE_CODE (gnu_decl) == CONST_DECL) DECL_CONST_ADDRESS_P (gnu_decl) = constructor_address_p (gnu_expr); /* If this object is declared in a block that contains a block with an exception handler, and we aren't using the GCC exception mechanism, we must force this variable in memory in order to avoid an invalid optimization. */ if (Exception_Mechanism != Back_End_Exceptions && Has_Nested_Block_With_Handler (Scope (gnat_entity))) TREE_ADDRESSABLE (gnu_decl) = 1; /* If this is a local variable with non-BLKmode and aggregate type, and optimization isn't enabled, then force it in memory so that a register won't be allocated to it with possible subparts left uninitialized and reaching the register allocator. */ else if (TREE_CODE (gnu_decl) == VAR_DECL && !DECL_EXTERNAL (gnu_decl) && !TREE_STATIC (gnu_decl) && DECL_MODE (gnu_decl) != BLKmode && AGGREGATE_TYPE_P (TREE_TYPE (gnu_decl)) && !TYPE_IS_FAT_POINTER_P (TREE_TYPE (gnu_decl)) && !optimize) TREE_ADDRESSABLE (gnu_decl) = 1; /* If we are defining an object with variable size or an object with fixed size that will be dynamically allocated, and we are using the setjmp/longjmp exception mechanism, update the setjmp buffer. */ if (definition && Exception_Mechanism == Setjmp_Longjmp && get_block_jmpbuf_decl () && DECL_SIZE_UNIT (gnu_decl) && (TREE_CODE (DECL_SIZE_UNIT (gnu_decl)) != INTEGER_CST || (flag_stack_check == GENERIC_STACK_CHECK && compare_tree_int (DECL_SIZE_UNIT (gnu_decl), STACK_CHECK_MAX_VAR_SIZE) > 0))) add_stmt_with_node (build_call_n_expr (update_setjmp_buf_decl, 1, build_unary_op (ADDR_EXPR, NULL_TREE, get_block_jmpbuf_decl ())), gnat_entity); /* Back-annotate Esize and Alignment of the object if not already known. Note that we pick the values of the type, not those of the object, to shield ourselves from low-level platform-dependent adjustments like alignment promotion. This is both consistent with all the treatment above, where alignment and size are set on the type of the object and not on the object directly, and makes it possible to support all confirming representation clauses. */ annotate_object (gnat_entity, TREE_TYPE (gnu_decl), gnu_object_size, used_by_ref); } break; case E_Void: /* Return a TYPE_DECL for "void" that we previously made. */ gnu_decl = TYPE_NAME (void_type_node); break; case E_Enumeration_Type: /* A special case: for the types Character and Wide_Character in Standard, we do not list all the literals. So if the literals are not specified, make this an unsigned integer type. */ if (No (First_Literal (gnat_entity))) { gnu_type = make_unsigned_type (esize); TYPE_NAME (gnu_type) = gnu_entity_name; /* Set TYPE_STRING_FLAG for Character and Wide_Character types. This is needed by the DWARF-2 back-end to distinguish between unsigned integer types and character types. */ TYPE_STRING_FLAG (gnu_type) = 1; } else { /* We have a list of enumeral constants in First_Literal. We make a CONST_DECL for each one and build into GNU_LITERAL_LIST the list to be placed into TYPE_FIELDS. Each node is itself a TREE_LIST whose TREE_VALUE is the literal name and whose TREE_PURPOSE is the value of the literal. But when we have a regular boolean type, we simplify this a little by using a BOOLEAN_TYPE. */ const bool is_boolean = Is_Boolean_Type (gnat_entity) && !Has_Non_Standard_Rep (gnat_entity); const bool is_unsigned = Is_Unsigned_Type (gnat_entity); tree gnu_list = NULL_TREE; Entity_Id gnat_literal; gnu_type = make_node (is_boolean ? BOOLEAN_TYPE : ENUMERAL_TYPE); TYPE_PRECISION (gnu_type) = esize; TYPE_UNSIGNED (gnu_type) = is_unsigned; set_min_and_max_values_for_integral_type (gnu_type, esize, TYPE_SIGN (gnu_type)); process_attributes (&gnu_type, &attr_list, true, gnat_entity); layout_type (gnu_type); for (gnat_literal = First_Literal (gnat_entity); Present (gnat_literal); gnat_literal = Next_Literal (gnat_literal)) { tree gnu_value = UI_To_gnu (Enumeration_Rep (gnat_literal), gnu_type); tree gnu_literal = create_var_decl (get_entity_name (gnat_literal), NULL_TREE, gnu_type, gnu_value, true, false, false, false, NULL, gnat_literal); /* Do not generate debug info for individual enumerators. */ DECL_IGNORED_P (gnu_literal) = 1; save_gnu_tree (gnat_literal, gnu_literal, false); gnu_list = tree_cons (DECL_NAME (gnu_literal), gnu_value, gnu_list); } if (!is_boolean) TYPE_VALUES (gnu_type) = nreverse (gnu_list); /* Note that the bounds are updated at the end of this function to avoid an infinite recursion since they refer to the type. */ goto discrete_type; } break; case E_Signed_Integer_Type: case E_Ordinary_Fixed_Point_Type: case E_Decimal_Fixed_Point_Type: /* For integer types, just make a signed type the appropriate number of bits. */ gnu_type = make_signed_type (esize); goto discrete_type; case E_Modular_Integer_Type: { /* For modular types, make the unsigned type of the proper number of bits and then set up the modulus, if required. */ tree gnu_modulus, gnu_high = NULL_TREE; /* Packed Array Impl. Types are supposed to be subtypes only. */ gcc_assert (!Is_Packed_Array_Impl_Type (gnat_entity)); gnu_type = make_unsigned_type (esize); /* Get the modulus in this type. If it overflows, assume it is because it is equal to 2**Esize. Note that there is no overflow checking done on unsigned type, so we detect the overflow by looking for a modulus of zero, which is otherwise invalid. */ gnu_modulus = UI_To_gnu (Modulus (gnat_entity), gnu_type); if (!integer_zerop (gnu_modulus)) { TYPE_MODULAR_P (gnu_type) = 1; SET_TYPE_MODULUS (gnu_type, gnu_modulus); gnu_high = fold_build2 (MINUS_EXPR, gnu_type, gnu_modulus, convert (gnu_type, integer_one_node)); } /* If the upper bound is not maximal, make an extra subtype. */ if (gnu_high && !tree_int_cst_equal (gnu_high, TYPE_MAX_VALUE (gnu_type))) { tree gnu_subtype = make_unsigned_type (esize); SET_TYPE_RM_MAX_VALUE (gnu_subtype, gnu_high); TREE_TYPE (gnu_subtype) = gnu_type; TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1; TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "UMT"); gnu_type = gnu_subtype; } } goto discrete_type; case E_Signed_Integer_Subtype: case E_Enumeration_Subtype: case E_Modular_Integer_Subtype: case E_Ordinary_Fixed_Point_Subtype: case E_Decimal_Fixed_Point_Subtype: /* For integral subtypes, we make a new INTEGER_TYPE. Note that we do not want to call create_range_type since we would like each subtype node to be distinct. ??? Historically this was in preparation for when memory aliasing is implemented, but that's obsolete now given the call to relate_alias_sets below. The TREE_TYPE field of the INTEGER_TYPE points to the base type; this fact is used by the arithmetic conversion functions. We elaborate the Ancestor_Subtype if it is not in the current unit and one of our bounds is non-static. We do this to ensure consistent naming in the case where several subtypes share the same bounds, by elaborating the first such subtype first, thus using its name. */ if (!definition && Present (Ancestor_Subtype (gnat_entity)) && !In_Extended_Main_Code_Unit (Ancestor_Subtype (gnat_entity)) && (!Compile_Time_Known_Value (Type_Low_Bound (gnat_entity)) || !Compile_Time_Known_Value (Type_High_Bound (gnat_entity)))) gnat_to_gnu_entity (Ancestor_Subtype (gnat_entity), gnu_expr, 0); /* Set the precision to the Esize except for bit-packed arrays. */ if (Is_Packed_Array_Impl_Type (gnat_entity) && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity))) esize = UI_To_Int (RM_Size (gnat_entity)); /* This should be an unsigned type if the base type is unsigned or if the lower bound is constant and non-negative or if the type is biased. */ if (Is_Unsigned_Type (Etype (gnat_entity)) || Is_Unsigned_Type (gnat_entity) || Has_Biased_Representation (gnat_entity)) gnu_type = make_unsigned_type (esize); else gnu_type = make_signed_type (esize); TREE_TYPE (gnu_type) = get_unpadded_type (Etype (gnat_entity)); SET_TYPE_RM_MIN_VALUE (gnu_type, elaborate_expression (Type_Low_Bound (gnat_entity), gnat_entity, "L", definition, true, Needs_Debug_Info (gnat_entity))); SET_TYPE_RM_MAX_VALUE (gnu_type, elaborate_expression (Type_High_Bound (gnat_entity), gnat_entity, "U", definition, true, Needs_Debug_Info (gnat_entity))); TYPE_BIASED_REPRESENTATION_P (gnu_type) = Has_Biased_Representation (gnat_entity); /* Inherit our alias set from what we're a subtype of. Subtypes are not different types and a pointer can designate any instance within a subtype hierarchy. */ relate_alias_sets (gnu_type, TREE_TYPE (gnu_type), ALIAS_SET_COPY); /* One of the above calls might have caused us to be elaborated, so don't blow up if so. */ if (present_gnu_tree (gnat_entity)) { maybe_present = true; break; } /* Attach the TYPE_STUB_DECL in case we have a parallel type. */ TYPE_STUB_DECL (gnu_type) = create_type_stub_decl (gnu_entity_name, gnu_type); /* For a packed array, make the original array type a parallel type. */ if (debug_info_p && Is_Packed_Array_Impl_Type (gnat_entity)) add_parallel_type_for_packed_array (gnu_type, gnat_entity); discrete_type: /* We have to handle clauses that under-align the type specially. */ if ((Present (Alignment_Clause (gnat_entity)) || (Is_Packed_Array_Impl_Type (gnat_entity) && Present (Alignment_Clause (Original_Array_Type (gnat_entity))))) && UI_Is_In_Int_Range (Alignment (gnat_entity))) { align = UI_To_Int (Alignment (gnat_entity)) * BITS_PER_UNIT; if (align >= TYPE_ALIGN (gnu_type)) align = 0; } /* If the type we are dealing with represents a bit-packed array, we need to have the bits left justified on big-endian targets and right justified on little-endian targets. We also need to ensure that when the value is read (e.g. for comparison of two such values), we only get the good bits, since the unused bits are uninitialized. Both goals are accomplished by wrapping up the modular type in an enclosing record type. */ if (Is_Packed_Array_Impl_Type (gnat_entity) && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity))) { tree gnu_field_type, gnu_field; /* Set the RM size before wrapping up the original type. */ SET_TYPE_RM_SIZE (gnu_type, UI_To_gnu (RM_Size (gnat_entity), bitsizetype)); TYPE_PACKED_ARRAY_TYPE_P (gnu_type) = 1; /* Create a stripped-down declaration, mainly for debugging. */ create_type_decl (gnu_entity_name, gnu_type, true, debug_info_p, gnat_entity); /* Now save it and build the enclosing record type. */ gnu_field_type = gnu_type; gnu_type = make_node (RECORD_TYPE); TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "JM"); TYPE_PACKED (gnu_type) = 1; TYPE_SIZE (gnu_type) = TYPE_SIZE (gnu_field_type); TYPE_SIZE_UNIT (gnu_type) = TYPE_SIZE_UNIT (gnu_field_type); SET_TYPE_ADA_SIZE (gnu_type, TYPE_RM_SIZE (gnu_field_type)); /* Propagate the alignment of the modular type to the record type, unless there is an alignment clause that under-aligns the type. This means that bit-packed arrays are given "ceil" alignment for their size by default, which may seem counter-intuitive but makes it possible to overlay them on modular types easily. */ TYPE_ALIGN (gnu_type) = align > 0 ? align : TYPE_ALIGN (gnu_field_type); relate_alias_sets (gnu_type, gnu_field_type, ALIAS_SET_COPY); /* Don't declare the field as addressable since we won't be taking its address and this would prevent create_field_decl from making a bitfield. */ gnu_field = create_field_decl (get_identifier ("OBJECT"), gnu_field_type, gnu_type, NULL_TREE, bitsize_zero_node, 1, 0); /* Do not emit debug info until after the parallel type is added. */ finish_record_type (gnu_type, gnu_field, 2, false); compute_record_mode (gnu_type); TYPE_JUSTIFIED_MODULAR_P (gnu_type) = 1; if (debug_info_p) { /* Make the original array type a parallel type. */ add_parallel_type_for_packed_array (gnu_type, gnat_entity); rest_of_record_type_compilation (gnu_type); } } /* If the type we are dealing with has got a smaller alignment than the natural one, we need to wrap it up in a record type and misalign the latter; we reuse the padding machinery for this purpose. Note that, even if the record type is marked as packed because of misalignment, we don't pack the field so as to give it the size of the type. */ else if (align > 0) { tree gnu_field_type, gnu_field; /* Set the RM size before wrapping up the type. */ SET_TYPE_RM_SIZE (gnu_type, UI_To_gnu (RM_Size (gnat_entity), bitsizetype)); /* Create a stripped-down declaration, mainly for debugging. */ create_type_decl (gnu_entity_name, gnu_type, true, debug_info_p, gnat_entity); /* Now save it and build the enclosing record type. */ gnu_field_type = gnu_type; gnu_type = make_node (RECORD_TYPE); TYPE_NAME (gnu_type) = create_concat_name (gnat_entity, "PAD"); TYPE_PACKED (gnu_type) = 1; TYPE_SIZE (gnu_type) = TYPE_SIZE (gnu_field_type); TYPE_SIZE_UNIT (gnu_type) = TYPE_SIZE_UNIT (gnu_field_type); SET_TYPE_ADA_SIZE (gnu_type, TYPE_RM_SIZE (gnu_field_type)); TYPE_ALIGN (gnu_type) = align; relate_alias_sets (gnu_type, gnu_field_type, ALIAS_SET_COPY); /* Don't declare the field as addressable since we won't be taking its address and this would prevent create_field_decl from making a bitfield. */ gnu_field = create_field_decl (get_identifier ("F"), gnu_field_type, gnu_type, TYPE_SIZE (gnu_field_type), bitsize_zero_node, 0, 0); finish_record_type (gnu_type, gnu_field, 2, debug_info_p); compute_record_mode (gnu_type); TYPE_PADDING_P (gnu_type) = 1; } break; case E_Floating_Point_Type: /* The type of the Low and High bounds can be our type if this is a type from Standard, so set them at the end of the function. */ gnu_type = make_node (REAL_TYPE); TYPE_PRECISION (gnu_type) = fp_size_to_prec (esize); layout_type (gnu_type); break; case E_Floating_Point_Subtype: /* See the E_Signed_Integer_Subtype case for the rationale. */ if (!definition && Present (Ancestor_Subtype (gnat_entity)) && !In_Extended_Main_Code_Unit (Ancestor_Subtype (gnat_entity)) && (!Compile_Time_Known_Value (Type_Low_Bound (gnat_entity)) || !Compile_Time_Known_Value (Type_High_Bound (gnat_entity)))) gnat_to_gnu_entity (Ancestor_Subtype (gnat_entity), gnu_expr, 0); gnu_type = make_node (REAL_TYPE); TREE_TYPE (gnu_type) = get_unpadded_type (Etype (gnat_entity)); TYPE_PRECISION (gnu_type) = fp_size_to_prec (esize); TYPE_GCC_MIN_VALUE (gnu_type) = TYPE_GCC_MIN_VALUE (TREE_TYPE (gnu_type)); TYPE_GCC_MAX_VALUE (gnu_type) = TYPE_GCC_MAX_VALUE (TREE_TYPE (gnu_type)); layout_type (gnu_type); SET_TYPE_RM_MIN_VALUE (gnu_type, elaborate_expression (Type_Low_Bound (gnat_entity), gnat_entity, "L", definition, true, Needs_Debug_Info (gnat_entity))); SET_TYPE_RM_MAX_VALUE (gnu_type, elaborate_expression (Type_High_Bound (gnat_entity), gnat_entity, "U", definition, true, Needs_Debug_Info (gnat_entity))); /* Inherit our alias set from what we're a subtype of, as for integer subtypes. */ relate_alias_sets (gnu_type, TREE_TYPE (gnu_type), ALIAS_SET_COPY); /* One of the above calls might have caused us to be elaborated, so don't blow up if so. */ maybe_present = true; break; /* Array Types and Subtypes Unconstrained array types are represented by E_Array_Type and constrained array types are represented by E_Array_Subtype. There are no actual objects of an unconstrained array type; all we have are pointers to that type. The following fields are defined on array types and subtypes: Component_Type Component type of the array. Number_Dimensions Number of dimensions (an int). First_Index Type of first index. */ case E_Array_Type: { const bool convention_fortran_p = (Convention (gnat_entity) == Convention_Fortran); const int ndim = Number_Dimensions (gnat_entity); tree gnu_template_type; tree gnu_ptr_template; tree gnu_template_reference, gnu_template_fields, gnu_fat_type; tree *gnu_index_types = XALLOCAVEC (tree, ndim); tree *gnu_temp_fields = XALLOCAVEC (tree, ndim); tree gnu_max_size = size_one_node, gnu_max_size_unit, tem, t; Entity_Id gnat_index, gnat_name; int index; tree comp_type; /* Create the type for the component now, as it simplifies breaking type reference loops. */ comp_type = gnat_to_gnu_component_type (gnat_entity, definition, debug_info_p); if (present_gnu_tree (gnat_entity)) { /* As a side effect, the type may have been translated. */ maybe_present = true; break; } /* We complete an existing dummy fat pointer type in place. This both avoids further complex adjustments in update_pointer_to and yields better debugging information in DWARF by leveraging the support for incomplete declarations of "tagged" types in the DWARF back-end. */ gnu_type = get_dummy_type (gnat_entity); if (gnu_type && TYPE_POINTER_TO (gnu_type)) { gnu_fat_type = TYPE_MAIN_VARIANT (TYPE_POINTER_TO (gnu_type)); TYPE_NAME (gnu_fat_type) = NULL_TREE; /* Save the contents of the dummy type for update_pointer_to. */ TYPE_POINTER_TO (gnu_type) = copy_type (gnu_fat_type); gnu_ptr_template = TREE_TYPE (TREE_CHAIN (TYPE_FIELDS (gnu_fat_type))); gnu_template_type = TREE_TYPE (gnu_ptr_template); } else { gnu_fat_type = make_node (RECORD_TYPE); gnu_template_type = make_node (RECORD_TYPE); gnu_ptr_template = build_pointer_type (gnu_template_type); } /* Make a node for the array. If we are not defining the array suppress expanding incomplete types. */ gnu_type = make_node (UNCONSTRAINED_ARRAY_TYPE); if (!definition) { defer_incomplete_level++; this_deferred = true; } /* Build the fat pointer type. Use a "void *" object instead of a pointer to the array type since we don't have the array type yet (it will reference the fat pointer via the bounds). */ tem = create_field_decl (get_identifier ("P_ARRAY"), ptr_type_node, gnu_fat_type, NULL_TREE, NULL_TREE, 0, 0); DECL_CHAIN (tem) = create_field_decl (get_identifier ("P_BOUNDS"), gnu_ptr_template, gnu_fat_type, NULL_TREE, NULL_TREE, 0, 0); if (COMPLETE_TYPE_P (gnu_fat_type)) { /* We are going to lay it out again so reset the alias set. */ alias_set_type alias_set = TYPE_ALIAS_SET (gnu_fat_type); TYPE_ALIAS_SET (gnu_fat_type) = -1; finish_fat_pointer_type (gnu_fat_type, tem); TYPE_ALIAS_SET (gnu_fat_type) = alias_set; for (t = gnu_fat_type; t; t = TYPE_NEXT_VARIANT (t)) { TYPE_FIELDS (t) = tem; SET_TYPE_UNCONSTRAINED_ARRAY (t, gnu_type); } } else { finish_fat_pointer_type (gnu_fat_type, tem); SET_TYPE_UNCONSTRAINED_ARRAY (gnu_fat_type, gnu_type); } /* Build a reference to the template from a PLACEHOLDER_EXPR that is the fat pointer. This will be used to access the individual fields once we build them. */ tem = build3 (COMPONENT_REF, gnu_ptr_template, build0 (PLACEHOLDER_EXPR, gnu_fat_type), DECL_CHAIN (TYPE_FIELDS (gnu_fat_type)), NULL_TREE); gnu_template_reference = build_unary_op (INDIRECT_REF, gnu_template_type, tem); TREE_READONLY (gnu_template_reference) = 1; TREE_THIS_NOTRAP (gnu_template_reference) = 1; /* Now create the GCC type for each index and add the fields for that index to the template. */ for (index = (convention_fortran_p ? ndim - 1 : 0), gnat_index = First_Index (gnat_entity); 0 <= index && index < ndim; index += (convention_fortran_p ? - 1 : 1), gnat_index = Next_Index (gnat_index)) { char field_name[16]; tree gnu_index_base_type = get_unpadded_type (Base_Type (Etype (gnat_index))); tree gnu_lb_field, gnu_hb_field, gnu_orig_min, gnu_orig_max; tree gnu_min, gnu_max, gnu_high; /* Make the FIELD_DECLs for the low and high bounds of this type and then make extractions of these fields from the template. */ sprintf (field_name, "LB%d", index); gnu_lb_field = create_field_decl (get_identifier (field_name), gnu_index_base_type, gnu_template_type, NULL_TREE, NULL_TREE, 0, 0); Sloc_to_locus (Sloc (gnat_entity), &DECL_SOURCE_LOCATION (gnu_lb_field)); field_name[0] = 'U'; gnu_hb_field = create_field_decl (get_identifier (field_name), gnu_index_base_type, gnu_template_type, NULL_TREE, NULL_TREE, 0, 0); Sloc_to_locus (Sloc (gnat_entity), &DECL_SOURCE_LOCATION (gnu_hb_field)); gnu_temp_fields[index] = chainon (gnu_lb_field, gnu_hb_field); /* We can't use build_component_ref here since the template type isn't complete yet. */ gnu_orig_min = build3 (COMPONENT_REF, gnu_index_base_type, gnu_template_reference, gnu_lb_field, NULL_TREE); gnu_orig_max = build3 (COMPONENT_REF, gnu_index_base_type, gnu_template_reference, gnu_hb_field, NULL_TREE); TREE_READONLY (gnu_orig_min) = TREE_READONLY (gnu_orig_max) = 1; gnu_min = convert (sizetype, gnu_orig_min); gnu_max = convert (sizetype, gnu_orig_max); /* Compute the size of this dimension. See the E_Array_Subtype case below for the rationale. */ gnu_high = build3 (COND_EXPR, sizetype, build2 (GE_EXPR, boolean_type_node, gnu_orig_max, gnu_orig_min), gnu_max, size_binop (MINUS_EXPR, gnu_min, size_one_node)); /* Make a range type with the new range in the Ada base type. Then make an index type with the size range in sizetype. */ gnu_index_types[index] = create_index_type (gnu_min, gnu_high, create_range_type (gnu_index_base_type, gnu_orig_min, gnu_orig_max), gnat_entity); /* Update the maximum size of the array in elements. */ if (gnu_max_size) { tree gnu_index_type = get_unpadded_type (Etype (gnat_index)); tree gnu_min = convert (sizetype, TYPE_MIN_VALUE (gnu_index_type)); tree gnu_max = convert (sizetype, TYPE_MAX_VALUE (gnu_index_type)); tree gnu_this_max = size_binop (PLUS_EXPR, size_one_node, size_binop (MINUS_EXPR, gnu_max, gnu_min)); if (TREE_CODE (gnu_this_max) == INTEGER_CST && TREE_OVERFLOW (gnu_this_max)) gnu_max_size = NULL_TREE; else gnu_max_size = size_binop (MULT_EXPR, gnu_max_size, gnu_this_max); } TYPE_NAME (gnu_index_types[index]) = create_concat_name (gnat_entity, field_name); } /* Install all the fields into the template. */ TYPE_NAME (gnu_template_type) = create_concat_name (gnat_entity, "XUB"); gnu_template_fields = NULL_TREE; for (index = 0; index < ndim; index++) gnu_template_fields = chainon (gnu_template_fields, gnu_temp_fields[index]); finish_record_type (gnu_template_type, gnu_template_fields, 0, debug_info_p); TYPE_READONLY (gnu_template_type) = 1; /* If Component_Size is not already specified, annotate it with the size of the component. */ if (Unknown_Component_Size (gnat_entity)) Set_Component_Size (gnat_entity, annotate_value (TYPE_SIZE (comp_type))); /* Compute the maximum size of the array in units and bits. */ if (gnu_max_size) { gnu_max_size_unit = size_binop (MULT_EXPR, gnu_max_size, TYPE_SIZE_UNIT (comp_type)); gnu_max_size = size_binop (MULT_EXPR, convert (bitsizetype, gnu_max_size), TYPE_SIZE (comp_type)); } else gnu_max_size_unit = NULL_TREE; /* Now build the array type. */ tem = comp_type; for (index = ndim - 1; index >= 0; index--) { tem = build_nonshared_array_type (tem, gnu_index_types[index]); if (Reverse_Storage_Order (gnat_entity) && !GNAT_Mode) sorry ("non-default Scalar_Storage_Order"); TYPE_MULTI_ARRAY_P (tem) = (index > 0); if (array_type_has_nonaliased_component (tem, gnat_entity)) TYPE_NONALIASED_COMPONENT (tem) = 1; } /* If an alignment is specified, use it if valid. But ignore it for the original type of packed array types. If the alignment was requested with an explicit alignment clause, state so. */ if (No (Packed_Array_Impl_Type (gnat_entity)) && Known_Alignment (gnat_entity)) { TYPE_ALIGN (tem) = validate_alignment (Alignment (gnat_entity), gnat_entity, TYPE_ALIGN (tem)); if (Present (Alignment_Clause (gnat_entity))) TYPE_USER_ALIGN (tem) = 1; } TYPE_CONVENTION_FORTRAN_P (tem) = convention_fortran_p; if (Treat_As_Volatile (gnat_entity)) tem = change_qualified_type (tem, TYPE_QUAL_VOLATILE); /* Adjust the type of the pointer-to-array field of the fat pointer and record the aliasing relationships if necessary. */ TREE_TYPE (TYPE_FIELDS (gnu_fat_type)) = build_pointer_type (tem); if (TYPE_ALIAS_SET_KNOWN_P (gnu_fat_type)) record_component_aliases (gnu_fat_type); /* The result type is an UNCONSTRAINED_ARRAY_TYPE that indicates the corresponding fat pointer. */ TREE_TYPE (gnu_type) = gnu_fat_type; TYPE_POINTER_TO (gnu_type) = gnu_fat_type; TYPE_REFERENCE_TO (gnu_type) = gnu_fat_type; SET_TYPE_MODE (gnu_type, BLKmode); TYPE_ALIGN (gnu_type) = TYPE_ALIGN (tem); /* If the maximum size doesn't overflow, use it. */ if (gnu_max_size && TREE_CODE (gnu_max_size) == INTEGER_CST && !TREE_OVERFLOW (gnu_max_size) && TREE_CODE (gnu_max_size_unit) == INTEGER_CST && !TREE_OVERFLOW (gnu_max_size_unit)) { TYPE_SIZE (tem) = size_binop (MIN_EXPR, gnu_max_size, TYPE_SIZE (tem)); TYPE_SIZE_UNIT (tem) = size_binop (MIN_EXPR, gnu_max_size_unit, TYPE_SIZE_UNIT (tem)); } create_type_decl (create_concat_name (gnat_entity, "XUA"), tem, !Comes_From_Source (gnat_entity), debug_info_p, gnat_entity); /* Give the fat pointer type a name. If this is a packed array, tell the debugger how to interpret the underlying bits. */ if (Present (Packed_Array_Impl_Type (gnat_entity))) gnat_name = Packed_Array_Impl_Type (gnat_entity); else gnat_name = gnat_entity; create_type_decl (create_concat_name (gnat_name, "XUP"), gnu_fat_type, !Comes_From_Source (gnat_entity), debug_info_p, gnat_entity); /* Create the type to be designated by thin pointers: a record type for the array and its template. We used to shift the fields to have the template at a negative offset, but this was somewhat of a kludge; we now shift thin pointer values explicitly but only those which have a TYPE_UNCONSTRAINED_ARRAY attached to the designated RECORD_TYPE. */ tem = build_unc_object_type (gnu_template_type, tem, create_concat_name (gnat_name, "XUT"), debug_info_p); SET_TYPE_UNCONSTRAINED_ARRAY (tem, gnu_type); TYPE_OBJECT_RECORD_TYPE (gnu_type) = tem; } break; case E_Array_Subtype: /* This is the actual data type for array variables. Multidimensional arrays are implemented as arrays of arrays. Note that arrays which have sparse enumeration subtypes as index components create sparse arrays, which is obviously space inefficient but so much easier to code for now. Also note that the subtype never refers to the unconstrained array type, which is somewhat at variance with Ada semantics. First check to see if this is simply a renaming of the array type. If so, the result is the array type. */ gnu_type = TYPE_MAIN_VARIANT (gnat_to_gnu_type (Etype (gnat_entity))); if (!Is_Constrained (gnat_entity)) ; else { Entity_Id gnat_index, gnat_base_index; const bool convention_fortran_p = (Convention (gnat_entity) == Convention_Fortran); const int ndim = Number_Dimensions (gnat_entity); tree gnu_base_type = gnu_type; tree *gnu_index_types = XALLOCAVEC (tree, ndim); tree gnu_max_size = size_one_node, gnu_max_size_unit; bool need_index_type_struct = false; int index; /* First create the GCC type for each index and find out whether special types are needed for debugging information. */ for (index = (convention_fortran_p ? ndim - 1 : 0), gnat_index = First_Index (gnat_entity), gnat_base_index = First_Index (Implementation_Base_Type (gnat_entity)); 0 <= index && index < ndim; index += (convention_fortran_p ? - 1 : 1), gnat_index = Next_Index (gnat_index), gnat_base_index = Next_Index (gnat_base_index)) { tree gnu_index_type = get_unpadded_type (Etype (gnat_index)); tree gnu_index_base_type = get_base_type (gnu_index_type); tree gnu_orig_min = convert (gnu_index_base_type, TYPE_MIN_VALUE (gnu_index_type)); tree gnu_orig_max = convert (gnu_index_base_type, TYPE_MAX_VALUE (gnu_index_type)); tree gnu_min = convert (sizetype, gnu_orig_min); tree gnu_max = convert (sizetype, gnu_orig_max); tree gnu_base_index_type = get_unpadded_type (Etype (gnat_base_index)); tree gnu_base_index_base_type = get_base_type (gnu_base_index_type); tree gnu_base_orig_min = convert (gnu_base_index_base_type, TYPE_MIN_VALUE (gnu_base_index_type)); tree gnu_base_orig_max = convert (gnu_base_index_base_type, TYPE_MAX_VALUE (gnu_base_index_type)); tree gnu_high; /* See if the base array type is already flat. If it is, we are probably compiling an ACATS test but it will cause the code below to malfunction if we don't handle it specially. */ if (TREE_CODE (gnu_base_orig_min) == INTEGER_CST && TREE_CODE (gnu_base_orig_max) == INTEGER_CST && tree_int_cst_lt (gnu_base_orig_max, gnu_base_orig_min)) { gnu_min = size_one_node; gnu_max = size_zero_node; gnu_high = gnu_max; } /* Similarly, if one of the values overflows in sizetype and the range is null, use 1..0 for the sizetype bounds. */ else if (TREE_CODE (gnu_min) == INTEGER_CST && TREE_CODE (gnu_max) == INTEGER_CST && (TREE_OVERFLOW (gnu_min) || TREE_OVERFLOW (gnu_max)) && tree_int_cst_lt (gnu_orig_max, gnu_orig_min)) { gnu_min = size_one_node; gnu_max = size_zero_node; gnu_high = gnu_max; } /* If the minimum and maximum values both overflow in sizetype, but the difference in the original type does not overflow in sizetype, ignore the overflow indication. */ else if (TREE_CODE (gnu_min) == INTEGER_CST && TREE_CODE (gnu_max) == INTEGER_CST && TREE_OVERFLOW (gnu_min) && TREE_OVERFLOW (gnu_max) && !TREE_OVERFLOW (convert (sizetype, fold_build2 (MINUS_EXPR, gnu_index_type, gnu_orig_max, gnu_orig_min)))) { TREE_OVERFLOW (gnu_min) = 0; TREE_OVERFLOW (gnu_max) = 0; gnu_high = gnu_max; } /* Compute the size of this dimension in the general case. We need to provide GCC with an upper bound to use but have to deal with the "superflat" case. There are three ways to do this. If we can prove that the array can never be superflat, we can just use the high bound of the index type. */ else if ((Nkind (gnat_index) == N_Range && cannot_be_superflat (gnat_index)) /* Bit-Packed Array Impl. Types are never superflat. */ || (Is_Packed_Array_Impl_Type (gnat_entity) && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity)))) gnu_high = gnu_max; /* Otherwise, if the high bound is constant but the low bound is not, we use the expression (hb >= lb) ? lb : hb + 1 for the lower bound. Note that the comparison must be done in the original type to avoid any overflow during the conversion. */ else if (TREE_CODE (gnu_max) == INTEGER_CST && TREE_CODE (gnu_min) != INTEGER_CST) { gnu_high = gnu_max; gnu_min = build_cond_expr (sizetype, build_binary_op (GE_EXPR, boolean_type_node, gnu_orig_max, gnu_orig_min), gnu_min, int_const_binop (PLUS_EXPR, gnu_max, size_one_node)); } /* Finally we use (hb >= lb) ? hb : lb - 1 for the upper bound in all the other cases. Note that, here as well as above, the condition used in the comparison must be equivalent to the condition (length != 0). This is relied upon in order to optimize array comparisons in compare_arrays. Moreover we use int_const_binop for the shift by 1 if the bound is constant to avoid any unwanted overflow. */ else gnu_high = build_cond_expr (sizetype, build_binary_op (GE_EXPR, boolean_type_node, gnu_orig_max, gnu_orig_min), gnu_max, TREE_CODE (gnu_min) == INTEGER_CST ? int_const_binop (MINUS_EXPR, gnu_min, size_one_node) : size_binop (MINUS_EXPR, gnu_min, size_one_node)); /* Reuse the index type for the range type. Then make an index type with the size range in sizetype. */ gnu_index_types[index] = create_index_type (gnu_min, gnu_high, gnu_index_type, gnat_entity); /* Update the maximum size of the array in elements. Here we see if any constraint on the index type of the base type can be used in the case of self-referential bound on the index type of the subtype. We look for a non-"infinite" and non-self-referential bound from any type involved and handle each bound separately. */ if (gnu_max_size) { tree gnu_base_min = convert (sizetype, gnu_base_orig_min); tree gnu_base_max = convert (sizetype, gnu_base_orig_max); tree gnu_base_index_base_type = get_base_type (gnu_base_index_type); tree gnu_base_base_min = convert (sizetype, TYPE_MIN_VALUE (gnu_base_index_base_type)); tree gnu_base_base_max = convert (sizetype, TYPE_MAX_VALUE (gnu_base_index_base_type)); if (!CONTAINS_PLACEHOLDER_P (gnu_min) || !(TREE_CODE (gnu_base_min) == INTEGER_CST && !TREE_OVERFLOW (gnu_base_min))) gnu_base_min = gnu_min; if (!CONTAINS_PLACEHOLDER_P (gnu_max) || !(TREE_CODE (gnu_base_max) == INTEGER_CST && !TREE_OVERFLOW (gnu_base_max))) gnu_base_max = gnu_max; if ((TREE_CODE (gnu_base_min) == INTEGER_CST && TREE_OVERFLOW (gnu_base_min)) || operand_equal_p (gnu_base_min, gnu_base_base_min, 0) || (TREE_CODE (gnu_base_max) == INTEGER_CST && TREE_OVERFLOW (gnu_base_max)) || operand_equal_p (gnu_base_max, gnu_base_base_max, 0)) gnu_max_size = NULL_TREE; else { tree gnu_this_max; /* Use int_const_binop if the bounds are constant to avoid any unwanted overflow. */ if (TREE_CODE (gnu_base_min) == INTEGER_CST && TREE_CODE (gnu_base_max) == INTEGER_CST) gnu_this_max = int_const_binop (PLUS_EXPR, size_one_node, int_const_binop (MINUS_EXPR, gnu_base_max, gnu_base_min)); else gnu_this_max = size_binop (PLUS_EXPR, size_one_node, size_binop (MINUS_EXPR, gnu_base_max, gnu_base_min)); gnu_max_size = size_binop (MULT_EXPR, gnu_max_size, gnu_this_max); } } /* We need special types for debugging information to point to the index types if they have variable bounds, are not integer types or are biased. */ if (TREE_CODE (gnu_orig_min) != INTEGER_CST || TREE_CODE (gnu_orig_max) != INTEGER_CST || TREE_CODE (gnu_index_type) != INTEGER_TYPE || (TREE_TYPE (gnu_index_type) && TREE_CODE (TREE_TYPE (gnu_index_type)) != INTEGER_TYPE) || TYPE_BIASED_REPRESENTATION_P (gnu_index_type)) need_index_type_struct = true; } /* Then flatten: create the array of arrays. For an array type used to implement a packed array, get the component type from the original array type since the representation clauses that can affect it are on the latter. */ if (Is_Packed_Array_Impl_Type (gnat_entity) && !Is_Bit_Packed_Array (Original_Array_Type (gnat_entity))) { gnu_type = gnat_to_gnu_type (Original_Array_Type (gnat_entity)); for (index = ndim - 1; index >= 0; index--) gnu_type = TREE_TYPE (gnu_type); /* One of the above calls might have caused us to be elaborated, so don't blow up if so. */ if (present_gnu_tree (gnat_entity)) { maybe_present = true; break; } } else { gnu_type = gnat_to_gnu_component_type (gnat_entity, definition, debug_info_p); /* One of the above calls might have caused us to be elaborated, so don't blow up if so. */ if (present_gnu_tree (gnat_entity)) { maybe_present = true; break; } } /* Compute the maximum size of the array in units and bits. */ if (gnu_max_size) { gnu_max_size_unit = size_binop (MULT_EXPR, gnu_max_size, TYPE_SIZE_UNIT (gnu_type)); gnu_max_size = size_binop (MULT_EXPR, convert (bitsizetype, gnu_max_size), TYPE_SIZE (gnu_type)); } else gnu_max_size_unit = NULL_TREE; /* Now build the array type. */ for (index = ndim - 1; index >= 0; index --) { gnu_type = build_nonshared_array_type (gnu_type, gnu_index_types[index]); TYPE_MULTI_ARRAY_P (gnu_type) = (index > 0); if (array_type_has_nonaliased_component (gnu_type, gnat_entity)) TYPE_NONALIASED_COMPONENT (gnu_type) = 1; } /* Attach the TYPE_STUB_DECL in case we have a parallel type. */ TYPE_STUB_DECL (gnu_type) = create_type_stub_decl (gnu_entity_name, gnu_type); /* If we are at file level and this is a multi-dimensional array, we need to make a variable corresponding to the stride of the inner dimensions. */ if (global_bindings_p () && ndim > 1) { tree gnu_arr_type; for (gnu_arr_type = TREE_TYPE (gnu_type), index = 1; TREE_CODE (gnu_arr_type) == ARRAY_TYPE; gnu_arr_type = TREE_TYPE (gnu_arr_type), index++) { tree eltype = TREE_TYPE (gnu_arr_type); char stride_name[32]; sprintf (stride_name, "ST%d", index); TYPE_SIZE (gnu_arr_type) = elaborate_expression_1 (TYPE_SIZE (gnu_arr_type), gnat_entity, stride_name, definition, false); /* ??? For now, store the size as a multiple of the alignment of the element type in bytes so that we can see the alignment from the tree. */ sprintf (stride_name, "ST%d_A_UNIT", index); TYPE_SIZE_UNIT (gnu_arr_type) = elaborate_expression_2 (TYPE_SIZE_UNIT (gnu_arr_type), gnat_entity, stride_name, definition, false, TYPE_ALIGN (eltype)); /* ??? create_type_decl is not invoked on the inner types so the MULT_EXPR node built above will never be marked. */ MARK_VISITED (TYPE_SIZE_UNIT (gnu_arr_type)); } } /* If we need to write out a record type giving the names of the bounds for debugging purposes, do it now and make the record type a parallel type. This is not needed for a packed array since the bounds are conveyed by the original array type. */ if (need_index_type_struct && debug_info_p && !Is_Packed_Array_Impl_Type (gnat_entity)) { tree gnu_bound_rec = make_node (RECORD_TYPE); tree gnu_field_list = NULL_TREE; tree gnu_field; TYPE_NAME (gnu_bound_rec) = create_concat_name (gnat_entity, "XA"); for (index = ndim - 1; index >= 0; index--) { tree gnu_index = TYPE_INDEX_TYPE (gnu_index_types[index]); tree gnu_index_name = TYPE_IDENTIFIER (gnu_index); /* Make sure to reference the types themselves, and not just their names, as the debugger may fall back on them. */ gnu_field = create_field_decl (gnu_index_name, gnu_index, gnu_bound_rec, NULL_TREE, NULL_TREE, 0, 0); DECL_CHAIN (gnu_field) = gnu_field_list; gnu_field_list = gnu_field; } finish_record_type (gnu_bound_rec, gnu_field_list, 0, true); add_parallel_type (gnu_type, gnu_bound_rec); } /* If this is a packed array type, make the original array type a parallel type. Otherwise, do it for the base array type if it isn't artificial to make sure it is kept in the debug info. */ if (debug_info_p) { if (Is_Packed_Array_Impl_Type (gnat_entity)) add_parallel_type_for_packed_array (gnu_type, gnat_entity); else { tree gnu_base_decl = gnat_to_gnu_entity (Etype (gnat_entity), NULL_TREE, 0); if (!DECL_ARTIFICIAL (gnu_base_decl)) add_parallel_type (gnu_type, TREE_TYPE (TREE_TYPE (gnu_base_decl))); } } TYPE_CONVENTION_FORTRAN_P (gnu_type) = convention_fortran_p; TYPE_PACKED_ARRAY_TYPE_P (gnu_type) = (Is_Packed_Array_Impl_Type (gnat_entity) && Is_Bit_Packed_Array (Original_Array_Type (gnat_entity))); /* If the size is self-referential and the maximum size doesn't overflow, use it. */ if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type)) && gnu_max_size && !(TREE_CODE (gnu_max_size) == INTEGER_CST && TREE_OVERFLOW (gnu_max_size)) && !(TREE_CODE (gnu_max_size_unit) == INTEGER_CST && TREE_OVERFLOW (gnu_max_size_unit))) { TYPE_SIZE (gnu_type) = size_binop (MIN_EXPR, gnu_max_size, TYPE_SIZE (gnu_type)); TYPE_SIZE_UNIT (gnu_type) = size_binop (MIN_EXPR, gnu_max_size_unit, TYPE_SIZE_UNIT (gnu_type)); } /* Set our alias set to that of our base type. This gives all array subtypes the same alias set. */ relate_alias_sets (gnu_type, gnu_base_type, ALIAS_SET_COPY); /* If this is a packed type, make this type the same as the packed array type, but do some adjusting in the type first. */ if (Present (Packed_Array_Impl_Type (gnat_entity))) { Entity_Id gnat_index; tree gnu_inner; /* First finish the type we had been making so that we output debugging information for it. */ process_attributes (&gnu_type, &attr_list, false, gnat_entity); if (Treat_As_Volatile (gnat_entity)) { const int quals = TYPE_QUAL_VOLATILE | (Is_Atomic_Or_VFA (gnat_entity) ? TYPE_QUAL_ATOMIC : 0); gnu_type = change_qualified_type (gnu_type, quals); } /* Make it artificial only if the base type was artificial too. That's sort of "morally" true and will make it possible for the debugger to look it up by name in DWARF, which is needed in order to decode the packed array type. */ gnu_decl = create_type_decl (gnu_entity_name, gnu_type, !Comes_From_Source (Etype (gnat_entity)) && !Comes_From_Source (gnat_entity), debug_info_p, gnat_entity); /* Save it as our equivalent in case the call below elaborates this type again. */ save_gnu_tree (gnat_entity, gnu_decl, false); gnu_decl = gnat_to_gnu_entity (Packed_Array_Impl_Type (gnat_entity), NULL_TREE, 0); this_made_decl = true; gnu_type = TREE_TYPE (gnu_decl); save_gnu_tree (gnat_entity, NULL_TREE, false); gnu_inner = gnu_type; while (TREE_CODE (gnu_inner) == RECORD_TYPE && (TYPE_JUSTIFIED_MODULAR_P (gnu_inner) || TYPE_PADDING_P (gnu_inner))) gnu_inner = TREE_TYPE (TYPE_FIELDS (gnu_inner)); /* We need to attach the index type to the type we just made so that the actual bounds can later be put into a template. */ if ((TREE_CODE (gnu_inner) == ARRAY_TYPE && !TYPE_ACTUAL_BOUNDS (gnu_inner)) || (TREE_CODE (gnu_inner) == INTEGER_TYPE && !TYPE_HAS_ACTUAL_BOUNDS_P (gnu_inner))) { if (TREE_CODE (gnu_inner) == INTEGER_TYPE) { /* The TYPE_ACTUAL_BOUNDS field is overloaded with the TYPE_MODULUS for modular types so we make an extra subtype if necessary. */ if (TYPE_MODULAR_P (gnu_inner)) { tree gnu_subtype = make_unsigned_type (TYPE_PRECISION (gnu_inner)); TREE_TYPE (gnu_subtype) = gnu_inner; TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1; SET_TYPE_RM_MIN_VALUE (gnu_subtype, TYPE_MIN_VALUE (gnu_inner)); SET_TYPE_RM_MAX_VALUE (gnu_subtype, TYPE_MAX_VALUE (gnu_inner)); gnu_inner = gnu_subtype; } TYPE_HAS_ACTUAL_BOUNDS_P (gnu_inner) = 1; #ifdef ENABLE_CHECKING /* Check for other cases of overloading. */ gcc_assert (!TYPE_ACTUAL_BOUNDS (gnu_inner)); #endif } for (gnat_index = First_Index (gnat_entity); Present (gnat_index); gnat_index = Next_Index (gnat_index)) SET_TYPE_ACTUAL_BOUNDS (gnu_inner, tree_cons (NULL_TREE, get_unpadded_type (Etype (gnat_index)), TYPE_ACTUAL_BOUNDS (gnu_inner))); if (Convention (gnat_entity) != Convention_Fortran) SET_TYPE_ACTUAL_BOUNDS (gnu_inner, nreverse (TYPE_ACTUAL_BOUNDS (gnu_inner))); if (TREE_CODE (gnu_type) == RECORD_TYPE && TYPE_JUSTIFIED_MODULAR_P (gnu_type)) TREE_TYPE (TYPE_FIELDS (gnu_type)) = gnu_inner; } } else /* Abort if packed array with no Packed_Array_Impl_Type. */ gcc_assert (!Is_Packed (gnat_entity)); } break; case E_String_Literal_Subtype: /* Create the type for a string literal. */ { Entity_Id gnat_full_type = (IN (Ekind (Etype (gnat_entity)), Private_Kind) && Present (Full_View (Etype (gnat_entity))) ? Full_View (Etype (gnat_entity)) : Etype (gnat_entity)); tree gnu_string_type = get_unpadded_type (gnat_full_type); tree gnu_string_array_type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_string_type)))); tree gnu_string_index_type = get_base_type (TREE_TYPE (TYPE_INDEX_TYPE (TYPE_DOMAIN (gnu_string_array_type)))); tree gnu_lower_bound = convert (gnu_string_index_type, gnat_to_gnu (String_Literal_Low_Bound (gnat_entity))); tree gnu_length = UI_To_gnu (String_Literal_Length (gnat_entity), gnu_string_index_type); tree gnu_upper_bound = build_binary_op (PLUS_EXPR, gnu_string_index_type, gnu_lower_bound, int_const_binop (MINUS_EXPR, gnu_length, convert (gnu_string_index_type, integer_one_node))); tree gnu_index_type = create_index_type (convert (sizetype, gnu_lower_bound), convert (sizetype, gnu_upper_bound), create_range_type (gnu_string_index_type, gnu_lower_bound, gnu_upper_bound), gnat_entity); gnu_type = build_nonshared_array_type (gnat_to_gnu_type (Component_Type (gnat_entity)), gnu_index_type); if (array_type_has_nonaliased_component (gnu_type, gnat_entity)) TYPE_NONALIASED_COMPONENT (gnu_type) = 1; relate_alias_sets (gnu_type, gnu_string_type, ALIAS_SET_COPY); } break; /* Record Types and Subtypes The following fields are defined on record types: Has_Discriminants True if the record has discriminants First_Discriminant Points to head of list of discriminants First_Entity Points to head of list of fields Is_Tagged_Type True if the record is tagged Implementation of Ada records and discriminated records: A record type definition is transformed into the equivalent of a C struct definition. The fields that are the discriminants which are found in the Full_Type_Declaration node and the elements of the Component_List found in the Record_Type_Definition node. The Component_List can be a recursive structure since each Variant of the Variant_Part of the Component_List has a Component_List. Processing of a record type definition comprises starting the list of field declarations here from the discriminants and the calling the function components_to_record to add the rest of the fields from the component list and return the gnu type node. The function components_to_record will call itself recursively as it traverses the tree. */ case E_Record_Type: if (Has_Complex_Representation (gnat_entity)) { gnu_type = build_complex_type (get_unpadded_type (Etype (Defining_Entity (First (Component_Items (Component_List (Type_Definition (Declaration_Node (gnat_entity))))))))); break; } { Node_Id full_definition = Declaration_Node (gnat_entity); Node_Id record_definition = Type_Definition (full_definition); Node_Id gnat_constr; Entity_Id gnat_field; tree gnu_field, gnu_field_list = NULL_TREE; tree gnu_get_parent; /* Set PACKED in keeping with gnat_to_gnu_field. */ const int packed = Is_Packed (gnat_entity) ? 1 : Component_Alignment (gnat_entity) == Calign_Storage_Unit ? -1 : (Known_Alignment (gnat_entity) || (Strict_Alignment (gnat_entity) && Known_RM_Size (gnat_entity))) ? -2 : 0; const bool has_discr = Has_Discriminants (gnat_entity); const bool has_rep = Has_Specified_Layout (gnat_entity); const bool is_extension = (Is_Tagged_Type (gnat_entity) && Nkind (record_definition) == N_Derived_Type_Definition); const bool is_unchecked_union = Is_Unchecked_Union (gnat_entity); bool all_rep = has_rep; /* See if all fields have a rep clause. Stop when we find one that doesn't. */ if (all_rep) for (gnat_field = First_Entity (gnat_entity); Present (gnat_field); gnat_field = Next_Entity (gnat_field)) if ((Ekind (gnat_field) == E_Component || Ekind (gnat_field) == E_Discriminant) && No (Component_Clause (gnat_field))) { all_rep = false; break; } /* If this is a record extension, go a level further to find the record definition. Also, verify we have a Parent_Subtype. */ if (is_extension) { if (!type_annotate_only || Present (Record_Extension_Part (record_definition))) record_definition = Record_Extension_Part (record_definition); gcc_assert (type_annotate_only || Present (Parent_Subtype (gnat_entity))); } /* Make a node for the record. If we are not defining the record, suppress expanding incomplete types. */ gnu_type = make_node (tree_code_for_record_type (gnat_entity)); TYPE_NAME (gnu_type) = gnu_entity_name; TYPE_PACKED (gnu_type) = (packed != 0) || has_rep; if (Reverse_Storage_Order (gnat_entity) && !GNAT_Mode) sorry ("non-default Scalar_Storage_Order"); process_attributes (&gnu_type, &attr_list, true, gnat_entity); if (!definition) { defer_incomplete_level++; this_deferred = true; } /* If both a size and rep clause was specified, put the size in the record type now so that it can get the proper mode. */ if (has_rep && Known_RM_Size (gnat_entity)) TYPE_SIZE (gnu_type) = UI_To_gnu (RM_Size (gnat_entity), bitsizetype); /* Always set the alignment here so that it can be used to set the mode, if it is making the alignment stricter. If it is invalid, it will be checked again below. If this is to be Atomic, choose a default alignment of a word unless we know the size and it's smaller. */ if (Known_Alignment (gnat_entity)) TYPE_ALIGN (gnu_type) = validate_alignment (Alignment (gnat_entity), gnat_entity, 0); else if (Is_Atomic_Or_VFA (gnat_entity) && Known_Esize (gnat_entity)) { unsigned int size = UI_To_Int (Esize (gnat_entity)); TYPE_ALIGN (gnu_type) = size >= BITS_PER_WORD ? BITS_PER_WORD : ceil_pow2 (size); } /* If a type needs strict alignment, the minimum size will be the type size instead of the RM size (see validate_size). Cap the alignment, lest it causes this type size to become too large. */ else if (Strict_Alignment (gnat_entity) && Known_RM_Size (gnat_entity)) { unsigned int raw_size = UI_To_Int (RM_Size (gnat_entity)); unsigned int raw_align = raw_size & -raw_size; if (raw_align < BIGGEST_ALIGNMENT) TYPE_ALIGN (gnu_type) = raw_align; } else TYPE_ALIGN (gnu_type) = 0; /* If we have a Parent_Subtype, make a field for the parent. If this record has rep clauses, force the position to zero. */ if (Present (Parent_Subtype (gnat_entity))) { Entity_Id gnat_parent = Parent_Subtype (gnat_entity); tree gnu_dummy_parent_type = make_node (RECORD_TYPE); tree gnu_parent; /* A major complexity here is that the parent subtype will reference our discriminants in its Stored_Constraint list. But those must reference the parent component of this record which is precisely of the parent subtype we have not built yet! To break the circle we first build a dummy COMPONENT_REF which represents the "get to the parent" operation and initialize each of those discriminants to a COMPONENT_REF of the above dummy parent referencing the corresponding discriminant of the base type of the parent subtype. */ gnu_get_parent = build3 (COMPONENT_REF, gnu_dummy_parent_type, build0 (PLACEHOLDER_EXPR, gnu_type), build_decl (input_location, FIELD_DECL, NULL_TREE, gnu_dummy_parent_type), NULL_TREE); if (has_discr) for (gnat_field = First_Stored_Discriminant (gnat_entity); Present (gnat_field); gnat_field = Next_Stored_Discriminant (gnat_field)) if (Present (Corresponding_Discriminant (gnat_field))) { tree gnu_field = gnat_to_gnu_field_decl (Corresponding_Discriminant (gnat_field)); save_gnu_tree (gnat_field, build3 (COMPONENT_REF, TREE_TYPE (gnu_field), gnu_get_parent, gnu_field, NULL_TREE), true); } /* Then we build the parent subtype. If it has discriminants but the type itself has unknown discriminants, this means that it doesn't contain information about how the discriminants are derived from those of the ancestor type, so it cannot be used directly. Instead it is built by cloning the parent subtype of the underlying record view of the type, for which the above derivation of discriminants has been made explicit. */ if (Has_Discriminants (gnat_parent) && Has_Unknown_Discriminants (gnat_entity)) { Entity_Id gnat_uview = Underlying_Record_View (gnat_entity); /* If we are defining the type, the underlying record view must already have been elaborated at this point. Otherwise do it now as its parent subtype cannot be technically elaborated on its own. */ if (definition) gcc_assert (present_gnu_tree (gnat_uview)); else gnat_to_gnu_entity (gnat_uview, NULL_TREE, 0); gnu_parent = gnat_to_gnu_type (Parent_Subtype (gnat_uview)); /* Substitute the "get to the parent" of the type for that of its underlying record view in the cloned type. */ for (gnat_field = First_Stored_Discriminant (gnat_uview); Present (gnat_field); gnat_field = Next_Stored_Discriminant (gnat_field)) if (Present (Corresponding_Discriminant (gnat_field))) { tree gnu_field = gnat_to_gnu_field_decl (gnat_field); tree gnu_ref = build3 (COMPONENT_REF, TREE_TYPE (gnu_field), gnu_get_parent, gnu_field, NULL_TREE); gnu_parent = substitute_in_type (gnu_parent, gnu_field, gnu_ref); } } else gnu_parent = gnat_to_gnu_type (gnat_parent); /* The parent field needs strict alignment so, if it is to be created with a component clause below, then we need to apply the same adjustment as in gnat_to_gnu_field. */ if (has_rep && TYPE_ALIGN (gnu_type) < TYPE_ALIGN (gnu_parent)) TYPE_ALIGN (gnu_type) = TYPE_ALIGN (gnu_parent); /* Finally we fix up both kinds of twisted COMPONENT_REF we have initially built. The discriminants must reference the fields of the parent subtype and not those of its base type for the placeholder machinery to properly work. */ if (has_discr) { /* The actual parent subtype is the full view. */ if (IN (Ekind (gnat_parent), Private_Kind)) { if (Present (Full_View (gnat_parent))) gnat_parent = Full_View (gnat_parent); else gnat_parent = Underlying_Full_View (gnat_parent); } for (gnat_field = First_Stored_Discriminant (gnat_entity); Present (gnat_field); gnat_field = Next_Stored_Discriminant (gnat_field)) if (Present (Corresponding_Discriminant (gnat_field))) { Entity_Id field; for (field = First_Stored_Discriminant (gnat_parent); Present (field); field = Next_Stored_Discriminant (field)) if (same_discriminant_p (gnat_field, field)) break; gcc_assert (Present (field)); TREE_OPERAND (get_gnu_tree (gnat_field), 1) = gnat_to_gnu_field_decl (field); } } /* The "get to the parent" COMPONENT_REF must be given its proper type... */ TREE_TYPE (gnu_get_parent) = gnu_parent; /* ...and reference the _Parent field of this record. */ gnu_field = create_field_decl (parent_name_id, gnu_parent, gnu_type, has_rep ? TYPE_SIZE (gnu_parent) : NULL_TREE, has_rep ? bitsize_zero_node : NULL_TREE, 0, 1); DECL_INTERNAL_P (gnu_field) = 1; TREE_OPERAND (gnu_get_parent, 1) = gnu_field; TYPE_FIELDS (gnu_type) = gnu_field; } /* Make the fields for the discriminants and put them into the record unless it's an Unchecked_Union. */ if (has_discr) for (gnat_field = First_Stored_Discriminant (gnat_entity); Present (gnat_field); gnat_field = Next_Stored_Discriminant (gnat_field)) { /* If this is a record extension and this discriminant is the renaming of another discriminant, we've handled it above. */ if (Present (Parent_Subtype (gnat_entity)) && Present (Corresponding_Discriminant (gnat_field))) continue; gnu_field = gnat_to_gnu_field (gnat_field, gnu_type, packed, definition, debug_info_p); /* Make an expression using a PLACEHOLDER_EXPR from the FIELD_DECL node just created and link that with the corresponding GNAT defining identifier. */ save_gnu_tree (gnat_field, build3 (COMPONENT_REF, TREE_TYPE (gnu_field), build0 (PLACEHOLDER_EXPR, gnu_type), gnu_field, NULL_TREE), true); if (!is_unchecked_union) { DECL_CHAIN (gnu_field) = gnu_field_list; gnu_field_list = gnu_field; } } /* If we have a derived untagged type that renames discriminants in the root type, the (stored) discriminants are a just copy of the discriminants of the root type. This means that any constraints added by the renaming in the derivation are disregarded as far as the layout of the derived type is concerned. To rescue them, we change the type of the (stored) discriminants to a subtype with the bounds of the type of the visible discriminants. */ if (has_discr && !is_extension && Stored_Constraint (gnat_entity) != No_Elist) for (gnat_constr = First_Elmt (Stored_Constraint (gnat_entity)); gnat_constr != No_Elmt; gnat_constr = Next_Elmt (gnat_constr)) if (Nkind (Node (gnat_constr)) == N_Identifier /* Ignore access discriminants. */ && !Is_Access_Type (Etype (Node (gnat_constr))) && Ekind (Entity (Node (gnat_constr))) == E_Discriminant) { Entity_Id gnat_discr = Entity (Node (gnat_constr)); tree gnu_discr_type, gnu_ref; /* If the scope of the discriminant is not the record type, this means that we're processing the implicit full view of a type derived from a private discriminated type: in this case, the Stored_Constraint list is simply copied from the partial view, see Build_Derived_Private_Type. So we need to retrieve the corresponding discriminant of the implicit full view, otherwise we will abort. */ if (Scope (gnat_discr) != gnat_entity) { Entity_Id field; for (field = First_Entity (gnat_entity); Present (field); field = Next_Entity (field)) if (Ekind (field) == E_Discriminant && same_discriminant_p (gnat_discr, field)) break; gcc_assert (Present (field)); gnat_discr = field; } gnu_discr_type = gnat_to_gnu_type (Etype (gnat_discr)); gnu_ref = gnat_to_gnu_entity (Original_Record_Component (gnat_discr), NULL_TREE, 0); /* GNU_REF must be an expression using a PLACEHOLDER_EXPR built just above for one of the stored discriminants. */ gcc_assert (TREE_TYPE (TREE_OPERAND (gnu_ref, 0)) == gnu_type); if (gnu_discr_type != TREE_TYPE (gnu_ref)) { const unsigned prec = TYPE_PRECISION (TREE_TYPE (gnu_ref)); tree gnu_subtype = TYPE_UNSIGNED (TREE_TYPE (gnu_ref)) ? make_unsigned_type (prec) : make_signed_type (prec); TREE_TYPE (gnu_subtype) = TREE_TYPE (gnu_ref); TYPE_EXTRA_SUBTYPE_P (gnu_subtype) = 1; SET_TYPE_RM_MIN_VALUE (gnu_subtype, TYPE_MIN_VALUE (gnu_discr_type)); SET_TYPE_RM_MAX_VALUE (gnu_subtype, TYPE_MAX_VALUE (gnu_discr_type)); TREE_TYPE (gnu_ref) = TREE_TYPE (TREE_OPERAND (gnu_ref, 1)) = gnu_subtype; } } /* Add the fields into the record type and finish it up. */ components_to_record (gnu_type, Component_List (record_definition), gnu_field_list, packed, definition, false, all_rep, is_unchecked_union, !Comes_From_Source (gnat_entity), debug_info_p, false, OK_To_Reorder_Components (gnat_entity), all_rep ? NULL_TREE : bitsize_zero_node, NULL); /* Fill in locations of fields. */ annotate_rep (gnat_entity, gnu_type); /* If there are any entities in the chain corresponding to components that we did not elaborate, ensure we elaborate their types if they are Itypes. */ for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp); gnat_temp = Next_Entity (gnat_temp)) if ((Ekind (gnat_temp) == E_Component || Ekind (gnat_temp) == E_Discriminant) && Is_Itype (Etype (gnat_temp)) && !present_gnu_tree (gnat_temp)) gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, 0); /* If this is a record type associated with an exception definition, equate its fields to those of the standard exception type. This will make it possible to convert between them. */ if (gnu_entity_name == exception_data_name_id) { tree gnu_std_field; for (gnu_field = TYPE_FIELDS (gnu_type), gnu_std_field = TYPE_FIELDS (except_type_node); gnu_field; gnu_field = DECL_CHAIN (gnu_field), gnu_std_field = DECL_CHAIN (gnu_std_field)) SET_DECL_ORIGINAL_FIELD_TO_FIELD (gnu_field, gnu_std_field); gcc_assert (!gnu_std_field); } } break; case E_Class_Wide_Subtype: /* If an equivalent type is present, that is what we should use. Otherwise, fall through to handle this like a record subtype since it may have constraints. */ if (gnat_equiv_type != gnat_entity) { gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0); maybe_present = true; break; } /* ... fall through ... */ case E_Record_Subtype: /* If Cloned_Subtype is Present it means this record subtype has identical layout to that type or subtype and we should use that GCC type for this one. The front end guarantees that the component list is shared. */ if (Present (Cloned_Subtype (gnat_entity))) { gnu_decl = gnat_to_gnu_entity (Cloned_Subtype (gnat_entity), NULL_TREE, 0); maybe_present = true; break; } /* Otherwise, first ensure the base type is elaborated. Then, if we are changing the type, make a new type with each field having the type of the field in the new subtype but the position computed by transforming every discriminant reference according to the constraints. We don't see any difference between private and non-private type here since derivations from types should have been deferred until the completion of the private type. */ else { Entity_Id gnat_base_type = Implementation_Base_Type (gnat_entity); tree gnu_base_type; if (!definition) { defer_incomplete_level++; this_deferred = true; } gnu_base_type = TYPE_MAIN_VARIANT (gnat_to_gnu_type (gnat_base_type)); if (present_gnu_tree (gnat_entity)) { maybe_present = true; break; } /* If this is a record subtype associated with a dispatch table, strip the suffix. This is necessary to make sure 2 different subtypes associated with the imported and exported views of a dispatch table are properly merged in LTO mode. */ if (Is_Dispatch_Table_Entity (gnat_entity)) { char *p; Get_Encoded_Name (gnat_entity); p = strchr (Name_Buffer, '_'); gcc_assert (p); strcpy (p+2, "dtS"); gnu_entity_name = get_identifier (Name_Buffer); } /* When the subtype has discriminants and these discriminants affect the initial shape it has inherited, factor them in. But for an Unchecked_Union (it must be an Itype), just return the type. We can't just test Is_Constrained because private subtypes without discriminants of types with discriminants with default expressions are Is_Constrained but aren't constrained! */ if (IN (Ekind (gnat_base_type), Record_Kind) && !Is_Unchecked_Union (gnat_base_type) && !Is_For_Access_Subtype (gnat_entity) && Has_Discriminants (gnat_entity) && Is_Constrained (gnat_entity) && Stored_Constraint (gnat_entity) != No_Elist) { vec gnu_subst_list = build_subst_list (gnat_entity, gnat_base_type, definition); tree gnu_unpad_base_type, gnu_rep_part, gnu_variant_part; tree gnu_pos_list, gnu_field_list = NULL_TREE; bool selected_variant = false, all_constant_pos = true; Entity_Id gnat_field; vec gnu_variant_list; gnu_type = make_node (RECORD_TYPE); TYPE_NAME (gnu_type) = gnu_entity_name; TYPE_PACKED (gnu_type) = TYPE_PACKED (gnu_base_type); process_attributes (&gnu_type, &attr_list, true, gnat_entity); /* Set the size, alignment and alias set of the new type to match that of the old one, doing required substitutions. */ copy_and_substitute_in_size (gnu_type, gnu_base_type, gnu_subst_list); if (TYPE_IS_PADDING_P (gnu_base_type)) gnu_unpad_base_type = TREE_TYPE (TYPE_FIELDS (gnu_base_type)); else gnu_unpad_base_type = gnu_base_type; /* Look for REP and variant parts in the base type. */ gnu_rep_part = get_rep_part (gnu_unpad_base_type); gnu_variant_part = get_variant_part (gnu_unpad_base_type); /* If there is a variant part, we must compute whether the constraints statically select a particular variant. If so, we simply drop the qualified union and flatten the list of fields. Otherwise we'll build a new qualified union for the variants that are still relevant. */ if (gnu_variant_part) { variant_desc *v; unsigned int i; gnu_variant_list = build_variant_list (TREE_TYPE (gnu_variant_part), gnu_subst_list, vNULL); /* If all the qualifiers are unconditionally true, the innermost variant is statically selected. */ selected_variant = true; FOR_EACH_VEC_ELT (gnu_variant_list, i, v) if (!integer_onep (v->qual)) { selected_variant = false; break; } /* Otherwise, create the new variants. */ if (!selected_variant) FOR_EACH_VEC_ELT (gnu_variant_list, i, v) { tree old_variant = v->type; tree new_variant = make_node (RECORD_TYPE); tree suffix = concat_name (DECL_NAME (gnu_variant_part), IDENTIFIER_POINTER (DECL_NAME (v->field))); TYPE_NAME (new_variant) = concat_name (TYPE_NAME (gnu_type), IDENTIFIER_POINTER (suffix)); copy_and_substitute_in_size (new_variant, old_variant, gnu_subst_list); v->new_type = new_variant; } } else { gnu_variant_list.create (0); selected_variant = false; } /* Make a list of fields and their position in the base type. */ gnu_pos_list = build_position_list (gnu_unpad_base_type, gnu_variant_list.exists () && !selected_variant, size_zero_node, bitsize_zero_node, BIGGEST_ALIGNMENT, NULL_TREE); /* Now go down every component in the subtype and compute its size and position from those of the component in the base type and from the constraints of the subtype. */ for (gnat_field = First_Entity (gnat_entity); Present (gnat_field); gnat_field = Next_Entity (gnat_field)) if ((Ekind (gnat_field) == E_Component || Ekind (gnat_field) == E_Discriminant) && !(Present (Corresponding_Discriminant (gnat_field)) && Is_Tagged_Type (gnat_base_type)) && Underlying_Type (Scope (Original_Record_Component (gnat_field))) == gnat_base_type) { Name_Id gnat_name = Chars (gnat_field); Entity_Id gnat_old_field = Original_Record_Component (gnat_field); tree gnu_old_field = gnat_to_gnu_field_decl (gnat_old_field); tree gnu_context = DECL_CONTEXT (gnu_old_field); tree gnu_field, gnu_field_type, gnu_size, gnu_pos; tree gnu_cont_type, gnu_last = NULL_TREE; /* If the type is the same, retrieve the GCC type from the old field to take into account possible adjustments. */ if (Etype (gnat_field) == Etype (gnat_old_field)) gnu_field_type = TREE_TYPE (gnu_old_field); else gnu_field_type = gnat_to_gnu_type (Etype (gnat_field)); /* If there was a component clause, the field types must be the same for the type and subtype, so copy the data from the old field to avoid recomputation here. Also if the field is justified modular and the optimization in gnat_to_gnu_field was applied. */ if (Present (Component_Clause (gnat_old_field)) || (TREE_CODE (gnu_field_type) == RECORD_TYPE && TYPE_JUSTIFIED_MODULAR_P (gnu_field_type) && TREE_TYPE (TYPE_FIELDS (gnu_field_type)) == TREE_TYPE (gnu_old_field))) { gnu_size = DECL_SIZE (gnu_old_field); gnu_field_type = TREE_TYPE (gnu_old_field); } /* If the old field was packed and of constant size, we have to get the old size here, as it might differ from what the Etype conveys and the latter might overlap onto the following field. Try to arrange the type for possible better packing along the way. */ else if (DECL_PACKED (gnu_old_field) && TREE_CODE (DECL_SIZE (gnu_old_field)) == INTEGER_CST) { gnu_size = DECL_SIZE (gnu_old_field); if (RECORD_OR_UNION_TYPE_P (gnu_field_type) && !TYPE_FAT_POINTER_P (gnu_field_type) && tree_fits_uhwi_p (TYPE_SIZE (gnu_field_type))) gnu_field_type = make_packable_type (gnu_field_type, true); } else gnu_size = TYPE_SIZE (gnu_field_type); /* If the context of the old field is the base type or its REP part (if any), put the field directly in the new type; otherwise look up the context in the variant list and put the field either in the new type if there is a selected variant or in one of the new variants. */ if (gnu_context == gnu_unpad_base_type || (gnu_rep_part && gnu_context == TREE_TYPE (gnu_rep_part))) gnu_cont_type = gnu_type; else { variant_desc *v; unsigned int i; tree rep_part; FOR_EACH_VEC_ELT (gnu_variant_list, i, v) if (gnu_context == v->type || ((rep_part = get_rep_part (v->type)) && gnu_context == TREE_TYPE (rep_part))) break; if (v) { if (selected_variant) gnu_cont_type = gnu_type; else gnu_cont_type = v->new_type; } else /* The front-end may pass us "ghost" components if it fails to recognize that a constrained subtype is statically constrained. Discard them. */ continue; } /* Now create the new field modeled on the old one. */ gnu_field = create_field_decl_from (gnu_old_field, gnu_field_type, gnu_cont_type, gnu_size, gnu_pos_list, gnu_subst_list); gnu_pos = DECL_FIELD_OFFSET (gnu_field); /* Put it in one of the new variants directly. */ if (gnu_cont_type != gnu_type) { DECL_CHAIN (gnu_field) = TYPE_FIELDS (gnu_cont_type); TYPE_FIELDS (gnu_cont_type) = gnu_field; } /* To match the layout crafted in components_to_record, if this is the _Tag or _Parent field, put it before any other fields. */ else if (gnat_name == Name_uTag || gnat_name == Name_uParent) gnu_field_list = chainon (gnu_field_list, gnu_field); /* Similarly, if this is the _Controller field, put it before the other fields except for the _Tag or _Parent field. */ else if (gnat_name == Name_uController && gnu_last) { DECL_CHAIN (gnu_field) = DECL_CHAIN (gnu_last); DECL_CHAIN (gnu_last) = gnu_field; } /* Otherwise, if this is a regular field, put it after the other fields. */ else { DECL_CHAIN (gnu_field) = gnu_field_list; gnu_field_list = gnu_field; if (!gnu_last) gnu_last = gnu_field; if (TREE_CODE (gnu_pos) != INTEGER_CST) all_constant_pos = false; } save_gnu_tree (gnat_field, gnu_field, false); } /* If there is a variant list, a selected variant and the fields all have a constant position, put them in order of increasing position to match that of constant CONSTRUCTORs. Likewise if there is no variant list but a REP part, since the latter has been flattened in the process. */ if (((gnu_variant_list.exists () && selected_variant) || (!gnu_variant_list.exists () && gnu_rep_part)) && all_constant_pos) { const int len = list_length (gnu_field_list); tree *field_arr = XALLOCAVEC (tree, len), t; int i; for (t = gnu_field_list, i = 0; t; t = DECL_CHAIN (t), i++) field_arr[i] = t; qsort (field_arr, len, sizeof (tree), compare_field_bitpos); gnu_field_list = NULL_TREE; for (i = 0; i < len; i++) { DECL_CHAIN (field_arr[i]) = gnu_field_list; gnu_field_list = field_arr[i]; } } /* If there is a variant list and no selected variant, we need to create the nest of variant parts from the old nest. */ else if (gnu_variant_list.exists () && !selected_variant) { tree new_variant_part = create_variant_part_from (gnu_variant_part, gnu_variant_list, gnu_type, gnu_pos_list, gnu_subst_list); DECL_CHAIN (new_variant_part) = gnu_field_list; gnu_field_list = new_variant_part; } /* Now go through the entities again looking for Itypes that we have not elaborated but should (e.g., Etypes of fields that have Original_Components). */ for (gnat_field = First_Entity (gnat_entity); Present (gnat_field); gnat_field = Next_Entity (gnat_field)) if ((Ekind (gnat_field) == E_Discriminant || Ekind (gnat_field) == E_Component) && !present_gnu_tree (Etype (gnat_field))) gnat_to_gnu_entity (Etype (gnat_field), NULL_TREE, 0); /* Do not emit debug info for the type yet since we're going to modify it below. */ finish_record_type (gnu_type, nreverse (gnu_field_list), 2, false); compute_record_mode (gnu_type); /* Fill in locations of fields. */ annotate_rep (gnat_entity, gnu_type); /* If debugging information is being written for the type, write a record that shows what we are a subtype of and also make a variable that indicates our size, if still variable. */ if (debug_info_p) { tree gnu_subtype_marker = make_node (RECORD_TYPE); tree gnu_unpad_base_name = TYPE_IDENTIFIER (gnu_unpad_base_type); tree gnu_size_unit = TYPE_SIZE_UNIT (gnu_type); TYPE_NAME (gnu_subtype_marker) = create_concat_name (gnat_entity, "XVS"); finish_record_type (gnu_subtype_marker, create_field_decl (gnu_unpad_base_name, build_reference_type (gnu_unpad_base_type), gnu_subtype_marker, NULL_TREE, NULL_TREE, 0, 0), 0, true); add_parallel_type (gnu_type, gnu_subtype_marker); if (definition && TREE_CODE (gnu_size_unit) != INTEGER_CST && !CONTAINS_PLACEHOLDER_P (gnu_size_unit)) TYPE_SIZE_UNIT (gnu_subtype_marker) = create_var_decl (create_concat_name (gnat_entity, "XVZ"), NULL_TREE, sizetype, gnu_size_unit, false, false, false, false, NULL, gnat_entity); } gnu_variant_list.release (); gnu_subst_list.release (); /* Now we can finalize it. */ rest_of_record_type_compilation (gnu_type); } /* Otherwise, go down all the components in the new type and make them equivalent to those in the base type. */ else { gnu_type = gnu_base_type; for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp); gnat_temp = Next_Entity (gnat_temp)) if ((Ekind (gnat_temp) == E_Discriminant && !Is_Unchecked_Union (gnat_base_type)) || Ekind (gnat_temp) == E_Component) save_gnu_tree (gnat_temp, gnat_to_gnu_field_decl (Original_Record_Component (gnat_temp)), false); } } break; case E_Access_Subprogram_Type: /* Use the special descriptor type for dispatch tables if needed, that is to say for the Prim_Ptr of a-tags.ads and its clones. Note that we are only required to do so for static tables in order to be compatible with the C++ ABI, but Ada 2005 allows to extend library level tagged types at the local level so we do it in the non-static case as well. */ if (TARGET_VTABLE_USES_DESCRIPTORS && Is_Dispatch_Table_Entity (gnat_entity)) { gnu_type = fdesc_type_node; gnu_size = TYPE_SIZE (gnu_type); break; } /* ... fall through ... */ case E_Anonymous_Access_Subprogram_Type: /* If we are not defining this entity, and we have incomplete entities being processed above us, make a dummy type and fill it in later. */ if (!definition && defer_incomplete_level != 0) { struct incomplete *p = XNEW (struct incomplete); gnu_type = build_pointer_type (make_dummy_type (Directly_Designated_Type (gnat_entity))); gnu_decl = create_type_decl (gnu_entity_name, gnu_type, !Comes_From_Source (gnat_entity), debug_info_p, gnat_entity); this_made_decl = true; gnu_type = TREE_TYPE (gnu_decl); save_gnu_tree (gnat_entity, gnu_decl, false); saved = true; p->old_type = TREE_TYPE (gnu_type); p->full_type = Directly_Designated_Type (gnat_entity); p->next = defer_incomplete_list; defer_incomplete_list = p; break; } /* ... fall through ... */ case E_Allocator_Type: case E_Access_Type: case E_Access_Attribute_Type: case E_Anonymous_Access_Type: case E_General_Access_Type: { /* The designated type and its equivalent type for gigi. */ Entity_Id gnat_desig_type = Directly_Designated_Type (gnat_entity); Entity_Id gnat_desig_equiv = Gigi_Equivalent_Type (gnat_desig_type); /* Whether it comes from a limited with. */ bool is_from_limited_with = (IN (Ekind (gnat_desig_equiv), Incomplete_Kind) && From_Limited_With (gnat_desig_equiv)); /* The "full view" of the designated type. If this is an incomplete entity from a limited with, treat its non-limited view as the full view. Otherwise, if this is an incomplete or private type, use the full view. In the former case, we might point to a private type, in which case, we need its full view. Also, we want to look at the actual type used for the representation, so this takes a total of three steps. */ Entity_Id gnat_desig_full_direct_first = (is_from_limited_with ? Non_Limited_View (gnat_desig_equiv) : (IN (Ekind (gnat_desig_equiv), Incomplete_Or_Private_Kind) ? Full_View (gnat_desig_equiv) : Empty)); Entity_Id gnat_desig_full_direct = ((is_from_limited_with && Present (gnat_desig_full_direct_first) && IN (Ekind (gnat_desig_full_direct_first), Private_Kind)) ? Full_View (gnat_desig_full_direct_first) : gnat_desig_full_direct_first); Entity_Id gnat_desig_full = Gigi_Equivalent_Type (gnat_desig_full_direct); /* The type actually used to represent the designated type, either gnat_desig_full or gnat_desig_equiv. */ Entity_Id gnat_desig_rep; /* True if this is a pointer to an unconstrained array. */ bool is_unconstrained_array; /* We want to know if we'll be seeing the freeze node for any incomplete type we may be pointing to. */ bool in_main_unit = (Present (gnat_desig_full) ? In_Extended_Main_Code_Unit (gnat_desig_full) : In_Extended_Main_Code_Unit (gnat_desig_type)); /* True if we make a dummy type here. */ bool made_dummy = false; /* The mode to be used for the pointer type. */ machine_mode p_mode = mode_for_size (esize, MODE_INT, 0); /* The GCC type used for the designated type. */ tree gnu_desig_type = NULL_TREE; if (!targetm.valid_pointer_mode (p_mode)) p_mode = ptr_mode; /* If either the designated type or its full view is an unconstrained array subtype, replace it with the type it's a subtype of. This avoids problems with multiple copies of unconstrained array types. Likewise, if the designated type is a subtype of an incomplete record type, use the parent type to avoid order of elaboration issues. This can lose some code efficiency, but there is no alternative. */ if (Ekind (gnat_desig_equiv) == E_Array_Subtype && !Is_Constrained (gnat_desig_equiv)) gnat_desig_equiv = Etype (gnat_desig_equiv); if (Present (gnat_desig_full) && ((Ekind (gnat_desig_full) == E_Array_Subtype && !Is_Constrained (gnat_desig_full)) || (Ekind (gnat_desig_full) == E_Record_Subtype && Ekind (Etype (gnat_desig_full)) == E_Record_Type))) gnat_desig_full = Etype (gnat_desig_full); /* Set the type that's actually the representation of the designated type and also flag whether we have a unconstrained array. */ gnat_desig_rep = Present (gnat_desig_full) ? gnat_desig_full : gnat_desig_equiv; is_unconstrained_array = Is_Array_Type (gnat_desig_rep) && !Is_Constrained (gnat_desig_rep); /* If we are pointing to an incomplete type whose completion is an unconstrained array, make dummy fat and thin pointer types to it. Likewise if the type itself is dummy or an unconstrained array. */ if (is_unconstrained_array && (Present (gnat_desig_full) || (present_gnu_tree (gnat_desig_equiv) && TYPE_IS_DUMMY_P (TREE_TYPE (get_gnu_tree (gnat_desig_equiv)))) || (!in_main_unit && defer_incomplete_level != 0 && !present_gnu_tree (gnat_desig_equiv)) || (in_main_unit && is_from_limited_with && Present (Freeze_Node (gnat_desig_equiv))))) { if (present_gnu_tree (gnat_desig_rep)) gnu_desig_type = TREE_TYPE (get_gnu_tree (gnat_desig_rep)); else { gnu_desig_type = make_dummy_type (gnat_desig_rep); made_dummy = true; } /* If the call above got something that has a pointer, the pointer is our type. This could have happened either because the type was elaborated or because somebody else executed the code. */ if (!TYPE_POINTER_TO (gnu_desig_type)) build_dummy_unc_pointer_types (gnat_desig_equiv, gnu_desig_type); gnu_type = TYPE_POINTER_TO (gnu_desig_type); } /* If we already know what the full type is, use it. */ else if (Present (gnat_desig_full) && present_gnu_tree (gnat_desig_full)) gnu_desig_type = TREE_TYPE (get_gnu_tree (gnat_desig_full)); /* Get the type of the thing we are to point to and build a pointer to it. If it is a reference to an incomplete or private type with a full view that is a record, make a dummy type node and get the actual type later when we have verified it is safe. */ else if ((!in_main_unit && !present_gnu_tree (gnat_desig_equiv) && Present (gnat_desig_full) && !present_gnu_tree (gnat_desig_full) && Is_Record_Type (gnat_desig_full)) /* Likewise if we are pointing to a record or array and we are to defer elaborating incomplete types. We do this as this access type may be the full view of a private type. Note that the unconstrained array case is handled above. */ || ((!in_main_unit || imported_p) && defer_incomplete_level != 0 && !present_gnu_tree (gnat_desig_equiv) && (Is_Record_Type (gnat_desig_rep) || Is_Array_Type (gnat_desig_rep))) /* If this is a reference from a limited_with type back to our main unit and there's a freeze node for it, either we have already processed the declaration and made the dummy type, in which case we just reuse the latter, or we have not yet, in which case we make the dummy type and it will be reused when the declaration is finally processed. In both cases, the pointer eventually created below will be automatically adjusted when the freeze node is processed. Note that the unconstrained array case is handled above. */ || (in_main_unit && is_from_limited_with && Present (Freeze_Node (gnat_desig_rep)))) { gnu_desig_type = make_dummy_type (gnat_desig_equiv); made_dummy = true; } /* Otherwise handle the case of a pointer to itself. */ else if (gnat_desig_equiv == gnat_entity) { gnu_type = build_pointer_type_for_mode (void_type_node, p_mode, No_Strict_Aliasing (gnat_entity)); TREE_TYPE (gnu_type) = TYPE_POINTER_TO (gnu_type) = gnu_type; } /* If expansion is disabled, the equivalent type of a concurrent type is absent, so build a dummy pointer type. */ else if (type_annotate_only && No (gnat_desig_equiv)) gnu_type = ptr_type_node; /* Finally, handle the default case where we can just elaborate our designated type. */ else gnu_desig_type = gnat_to_gnu_type (gnat_desig_equiv); /* It is possible that a call to gnat_to_gnu_type above resolved our type. If so, just return it. */ if (present_gnu_tree (gnat_entity)) { maybe_present = true; break; } /* If we haven't done it yet, build the pointer type the usual way. */ if (!gnu_type) { /* Modify the designated type if we are pointing only to constant objects, but don't do it for unconstrained arrays. */ if (Is_Access_Constant (gnat_entity) && TREE_CODE (gnu_desig_type) != UNCONSTRAINED_ARRAY_TYPE) { gnu_desig_type = change_qualified_type (gnu_desig_type, TYPE_QUAL_CONST); /* Some extra processing is required if we are building a pointer to an incomplete type (in the GCC sense). We might have such a type if we just made a dummy, or directly out of the call to gnat_to_gnu_type above if we are processing an access type for a record component designating the record type itself. */ if (TYPE_MODE (gnu_desig_type) == VOIDmode) { /* We must ensure that the pointer to variant we make will be processed by update_pointer_to when the initial type is completed. Pretend we made a dummy and let further processing act as usual. */ made_dummy = true; /* We must ensure that update_pointer_to will not retrieve the dummy variant when building a properly qualified version of the complete type. We take advantage of the fact that get_qualified_type is requiring TYPE_NAMEs to match to influence build_qualified_type and then also update_pointer_to here. */ TYPE_NAME (gnu_desig_type) = create_concat_name (gnat_desig_type, "INCOMPLETE_CST"); } } gnu_type = build_pointer_type_for_mode (gnu_desig_type, p_mode, No_Strict_Aliasing (gnat_entity)); } /* If we are not defining this object and we have made a dummy pointer, save our current definition, evaluate the actual type, and replace the tentative type we made with the actual one. If we are to defer actually looking up the actual type, make an entry in the deferred list. If this is from a limited with, we may have to defer to the end of the current unit. */ if ((!in_main_unit || is_from_limited_with) && made_dummy) { tree gnu_old_desig_type; if (TYPE_IS_FAT_POINTER_P (gnu_type)) { gnu_old_desig_type = TYPE_UNCONSTRAINED_ARRAY (gnu_type); if (esize == POINTER_SIZE) gnu_type = build_pointer_type (TYPE_OBJECT_RECORD_TYPE (gnu_old_desig_type)); } else gnu_old_desig_type = TREE_TYPE (gnu_type); process_attributes (&gnu_type, &attr_list, false, gnat_entity); gnu_decl = create_type_decl (gnu_entity_name, gnu_type, !Comes_From_Source (gnat_entity), debug_info_p, gnat_entity); this_made_decl = true; gnu_type = TREE_TYPE (gnu_decl); save_gnu_tree (gnat_entity, gnu_decl, false); saved = true; /* Note that the call to gnat_to_gnu_type on gnat_desig_equiv might update gnu_old_desig_type directly, in which case it will not be a dummy type any more when we get into update_pointer_to. This can happen e.g. when the designated type is a record type, because their elaboration starts with an initial node from make_dummy_type, which may be the same node as the one we got. Besides, variants of this non-dummy type might have been created along the way. update_pointer_to is expected to properly take care of those situations. */ if (defer_incomplete_level == 0 && !is_from_limited_with) { update_pointer_to (TYPE_MAIN_VARIANT (gnu_old_desig_type), gnat_to_gnu_type (gnat_desig_equiv)); } else { struct incomplete *p = XNEW (struct incomplete); struct incomplete **head = (is_from_limited_with ? &defer_limited_with : &defer_incomplete_list); p->old_type = gnu_old_desig_type; p->full_type = gnat_desig_equiv; p->next = *head; *head = p; } } } break; case E_Access_Protected_Subprogram_Type: case E_Anonymous_Access_Protected_Subprogram_Type: if (type_annotate_only && No (gnat_equiv_type)) gnu_type = ptr_type_node; else { /* The run-time representation is the equivalent type. */ gnu_type = gnat_to_gnu_type (gnat_equiv_type); maybe_present = true; } if (Is_Itype (Directly_Designated_Type (gnat_entity)) && !present_gnu_tree (Directly_Designated_Type (gnat_entity)) && No (Freeze_Node (Directly_Designated_Type (gnat_entity))) && !Is_Record_Type (Scope (Directly_Designated_Type (gnat_entity)))) gnat_to_gnu_entity (Directly_Designated_Type (gnat_entity), NULL_TREE, 0); break; case E_Access_Subtype: /* We treat this as identical to its base type; any constraint is meaningful only to the front-end. The designated type must be elaborated as well, if it does not have its own freeze node. Designated (sub)types created for constrained components of records with discriminants are not frozen by the front-end and thus not elaborated by gigi, because their use may appear before the base type is frozen, and because it is not clear that they are needed anywhere in gigi. With the current model, there is no correct place where they could be elaborated. */ gnu_type = gnat_to_gnu_type (Etype (gnat_entity)); if (Is_Itype (Directly_Designated_Type (gnat_entity)) && !present_gnu_tree (Directly_Designated_Type (gnat_entity)) && Is_Frozen (Directly_Designated_Type (gnat_entity)) && No (Freeze_Node (Directly_Designated_Type (gnat_entity)))) { /* If we are not defining this entity, and we have incomplete entities being processed above us, make a dummy type and elaborate it later. */ if (!definition && defer_incomplete_level != 0) { struct incomplete *p = XNEW (struct incomplete); p->old_type = make_dummy_type (Directly_Designated_Type (gnat_entity)); p->full_type = Directly_Designated_Type (gnat_entity); p->next = defer_incomplete_list; defer_incomplete_list = p; } else if (!IN (Ekind (Base_Type (Directly_Designated_Type (gnat_entity))), Incomplete_Or_Private_Kind)) gnat_to_gnu_entity (Directly_Designated_Type (gnat_entity), NULL_TREE, 0); } maybe_present = true; break; /* Subprogram Entities The following access functions are defined for subprograms: Etype Return type or Standard_Void_Type. First_Formal The first formal parameter. Is_Imported Indicates that the subprogram has appeared in an INTERFACE or IMPORT pragma. For now we assume that the external language is C. Is_Exported Likewise but for an EXPORT pragma. Is_Inlined True if the subprogram is to be inlined. Each parameter is first checked by calling must_pass_by_ref on its type to determine if it is passed by reference. For parameters which are copied in, if they are Ada In Out or Out parameters, their return value becomes part of a record which becomes the return type of the function (C function - note that this applies only to Ada procedures so there is no Ada return type). Additional code to store back the parameters will be generated on the caller side. This transformation is done here, not in the front-end. The intended result of the transformation can be seen from the equivalent source rewritings that follow: struct temp {int a,b}; procedure P (A,B: In Out ...) is temp P (int A,B) begin { .. .. end P; return {A,B}; } temp t; P(X,Y); t = P(X,Y); X = t.a , Y = t.b; For subprogram types we need to perform mainly the same conversions to GCC form that are needed for procedures and function declarations. The only difference is that at the end, we make a type declaration instead of a function declaration. */ case E_Subprogram_Type: case E_Function: case E_Procedure: { /* The type returned by a function or else Standard_Void_Type for a procedure. */ Entity_Id gnat_return_type = Etype (gnat_entity); tree gnu_return_type; /* The first GCC parameter declaration (a PARM_DECL node). The PARM_DECL nodes are chained through the DECL_CHAIN field, so this actually is the head of this parameter list. */ tree gnu_param_list = NULL_TREE; /* Non-null for subprograms containing parameters passed by copy-in copy-out (Ada In Out or Out parameters not passed by reference), in which case it is the list of nodes used to specify the values of the In Out/Out parameters that are returned as a record upon procedure return. The TREE_PURPOSE of an element of this list is a field of the record and the TREE_VALUE is the PARM_DECL corresponding to that field. This list will be saved in the TYPE_CI_CO_LIST field of the FUNCTION_TYPE node we create. */ tree gnu_cico_list = NULL_TREE; /* List of fields in return type of procedure with copy-in copy-out parameters. */ tree gnu_field_list = NULL_TREE; /* If an import pragma asks to map this subprogram to a GCC builtin, this is the builtin DECL node. */ tree gnu_builtin_decl = NULL_TREE; tree gnu_ext_name = create_concat_name (gnat_entity, NULL); Entity_Id gnat_param; enum inline_status_t inline_status = Has_Pragma_No_Inline (gnat_entity) ? is_suppressed : Has_Pragma_Inline_Always (gnat_entity) ? is_required : (Is_Inlined (gnat_entity) ? is_enabled : is_disabled); bool public_flag = Is_Public (gnat_entity) || imported_p; /* Subprograms marked both Intrinsic and Always_Inline need not have a body of their own. */ bool extern_flag = ((Is_Public (gnat_entity) && !definition) || imported_p || (Convention (gnat_entity) == Convention_Intrinsic && Has_Pragma_Inline_Always (gnat_entity))); bool artificial_flag = !Comes_From_Source (gnat_entity); /* The semantics of "pure" in Ada essentially matches that of "const" in the back-end. In particular, both properties are orthogonal to the "nothrow" property if the EH circuitry is explicit in the internal representation of the back-end. If we are to completely hide the EH circuitry from it, we need to declare that calls to pure Ada subprograms that can throw have side effects since they can trigger an "abnormal" transfer of control flow; thus they can be neither "const" nor "pure" in the back-end sense. */ bool const_flag = (Exception_Mechanism == Back_End_Exceptions && Is_Pure (gnat_entity)); bool noreturn_flag = No_Return (gnat_entity); bool return_by_direct_ref_p = false; bool return_by_invisi_ref_p = false; bool return_unconstrained_p = false; int parmnum; /* A parameter may refer to this type, so defer completion of any incomplete types. */ if (kind == E_Subprogram_Type && !definition) { defer_incomplete_level++; this_deferred = true; } /* If the subprogram has an alias, it is probably inherited, so we can use the original one. If the original "subprogram" is actually an enumeration literal, it may be the first use of its type, so we must elaborate that type now. */ if (Present (Alias (gnat_entity))) { if (Ekind (Alias (gnat_entity)) == E_Enumeration_Literal) gnat_to_gnu_entity (Etype (Alias (gnat_entity)), NULL_TREE, 0); gnu_decl = gnat_to_gnu_entity (Alias (gnat_entity), gnu_expr, 0); /* Elaborate any Itypes in the parameters of this entity. */ for (gnat_temp = First_Formal_With_Extras (gnat_entity); Present (gnat_temp); gnat_temp = Next_Formal_With_Extras (gnat_temp)) if (Is_Itype (Etype (gnat_temp))) gnat_to_gnu_entity (Etype (gnat_temp), NULL_TREE, 0); break; } /* If this subprogram is expectedly bound to a GCC builtin, fetch the corresponding DECL node. Proper generation of calls later on need proper parameter associations so we don't "break;" here. */ if (Convention (gnat_entity) == Convention_Intrinsic && Present (Interface_Name (gnat_entity))) { gnu_builtin_decl = builtin_decl_for (gnu_ext_name); /* Inability to find the builtin decl most often indicates a genuine mistake, but imports of unregistered intrinsics are sometimes issued on purpose to allow hooking in alternate bodies. We post a warning conditioned on Wshadow in this case, to let developers be notified on demand without risking false positives with common default sets of options. */ if (gnu_builtin_decl == NULL_TREE && warn_shadow) post_error ("?gcc intrinsic not found for&!", gnat_entity); } /* ??? What if we don't find the builtin node above ? warn ? err ? In the current state we neither warn nor err, and calls will just be handled as for regular subprograms. */ /* Look into the return type and get its associated GCC tree. If it is not void, compute various flags for the subprogram type. */ if (Ekind (gnat_return_type) == E_Void) gnu_return_type = void_type_node; else { /* Ada 2012 (AI05-0151): Incomplete types coming from a limited context may now appear in parameter and result profiles. If we are only annotating types, break circularities here. */ if (type_annotate_only && is_from_limited_with_of_main (gnat_return_type)) gnu_return_type = void_type_node; else gnu_return_type = gnat_to_gnu_type (gnat_return_type); /* If this function returns by reference, make the actual return type the pointer type and make a note of that. */ if (Returns_By_Ref (gnat_entity)) { gnu_return_type = build_reference_type (gnu_return_type); return_by_direct_ref_p = true; } /* If the return type is an unconstrained array type, the return value will be allocated on the secondary stack so the actual return type is the fat pointer type. */ else if (TREE_CODE (gnu_return_type) == UNCONSTRAINED_ARRAY_TYPE) { gnu_return_type = TREE_TYPE (gnu_return_type); return_unconstrained_p = true; } /* Likewise, if the return type requires a transient scope, the return value will also be allocated on the secondary stack so the actual return type is the pointer type. */ else if (Requires_Transient_Scope (gnat_return_type)) { gnu_return_type = build_reference_type (gnu_return_type); return_unconstrained_p = true; } /* If the Mechanism is By_Reference, ensure this function uses the target's by-invisible-reference mechanism, which may not be the same as above (e.g. it might be passing an extra parameter). */ else if (kind == E_Function && Mechanism (gnat_entity) == By_Reference) return_by_invisi_ref_p = true; /* Likewise, if the return type is itself By_Reference. */ else if (TYPE_IS_BY_REFERENCE_P (gnu_return_type)) return_by_invisi_ref_p = true; /* If the type is a padded type and the underlying type would not be passed by reference or the function has a foreign convention, return the underlying type. */ else if (TYPE_IS_PADDING_P (gnu_return_type) && (!default_pass_by_ref (TREE_TYPE (TYPE_FIELDS (gnu_return_type))) || Has_Foreign_Convention (gnat_entity))) gnu_return_type = TREE_TYPE (TYPE_FIELDS (gnu_return_type)); /* If the return type is unconstrained, that means it must have a maximum size. Use the padded type as the effective return type. And ensure the function uses the target's by-invisible-reference mechanism to avoid copying too much data when it returns. */ if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_return_type))) { tree orig_type = gnu_return_type; gnu_return_type = maybe_pad_type (gnu_return_type, max_size (TYPE_SIZE (gnu_return_type), true), 0, gnat_entity, false, false, definition, true); /* Declare it now since it will never be declared otherwise. This is necessary to ensure that its subtrees are properly marked. */ if (gnu_return_type != orig_type && !DECL_P (TYPE_NAME (gnu_return_type))) create_type_decl (TYPE_NAME (gnu_return_type), gnu_return_type, true, debug_info_p, gnat_entity); return_by_invisi_ref_p = true; } /* If the return type has a size that overflows, we cannot have a function that returns that type. This usage doesn't make sense anyway, so give an error here. */ if (!return_by_invisi_ref_p && TYPE_SIZE_UNIT (gnu_return_type) && TREE_CODE (TYPE_SIZE_UNIT (gnu_return_type)) == INTEGER_CST && !valid_constant_size_p (TYPE_SIZE_UNIT (gnu_return_type))) { post_error ("cannot return type whose size overflows", gnat_entity); gnu_return_type = copy_node (gnu_return_type); TYPE_SIZE (gnu_return_type) = bitsize_zero_node; TYPE_SIZE_UNIT (gnu_return_type) = size_zero_node; TYPE_MAIN_VARIANT (gnu_return_type) = gnu_return_type; TYPE_NEXT_VARIANT (gnu_return_type) = NULL_TREE; } } /* Loop over the parameters and get their associated GCC tree. While doing this, build a copy-in copy-out structure if we need one. */ for (gnat_param = First_Formal_With_Extras (gnat_entity), parmnum = 0; Present (gnat_param); gnat_param = Next_Formal_With_Extras (gnat_param), parmnum++) { Entity_Id gnat_param_type = Etype (gnat_param); tree gnu_param_name = get_entity_name (gnat_param); tree gnu_param_type, gnu_param, gnu_field; Mechanism_Type mech = Mechanism (gnat_param); bool copy_in_copy_out = false, fake_param_type; /* Ada 2012 (AI05-0151): Incomplete types coming from a limited context may now appear in parameter and result profiles. If we are only annotating types, break circularities here. */ if (type_annotate_only && is_from_limited_with_of_main (gnat_param_type)) { gnu_param_type = void_type_node; fake_param_type = true; } else { gnu_param_type = gnat_to_gnu_type (gnat_param_type); fake_param_type = false; } /* Builtins are expanded inline and there is no real call sequence involved. So the type expected by the underlying expander is always the type of each argument "as is". */ if (gnu_builtin_decl) mech = By_Copy; /* Handle the first parameter of a valued procedure specially. */ else if (Is_Valued_Procedure (gnat_entity) && parmnum == 0) mech = By_Copy_Return; /* Otherwise, see if a Mechanism was supplied that forced this parameter to be passed one way or another. */ else if (mech == Default || mech == By_Copy || mech == By_Reference) ; else if (mech > 0) { if (TREE_CODE (gnu_param_type) == UNCONSTRAINED_ARRAY_TYPE || TREE_CODE (TYPE_SIZE (gnu_param_type)) != INTEGER_CST || 0 < compare_tree_int (TYPE_SIZE (gnu_param_type), mech)) mech = By_Reference; else mech = By_Copy; } else { post_error ("unsupported mechanism for&", gnat_param); mech = Default; } /* Do not call gnat_to_gnu_param for a fake parameter type since it will try to use the real type again. */ if (fake_param_type) { if (Ekind (gnat_param) == E_Out_Parameter) gnu_param = NULL_TREE; else { gnu_param = create_param_decl (gnu_param_name, gnu_param_type, false); Set_Mechanism (gnat_param, mech == Default ? By_Copy : mech); if (Ekind (gnat_param) == E_In_Out_Parameter) copy_in_copy_out = true; } } else gnu_param = gnat_to_gnu_param (gnat_param, mech, gnat_entity, Has_Foreign_Convention (gnat_entity), ©_in_copy_out); /* We are returned either a PARM_DECL or a type if no parameter needs to be passed; in either case, adjust the type. */ if (DECL_P (gnu_param)) gnu_param_type = TREE_TYPE (gnu_param); else { gnu_param_type = gnu_param; gnu_param = NULL_TREE; } /* The failure of this assertion will very likely come from an order of elaboration issue for the type of the parameter. */ gcc_assert (kind == E_Subprogram_Type || !TYPE_IS_DUMMY_P (gnu_param_type) || type_annotate_only); if (gnu_param) { gnu_param_list = chainon (gnu_param, gnu_param_list); Sloc_to_locus (Sloc (gnat_param), &DECL_SOURCE_LOCATION (gnu_param)); save_gnu_tree (gnat_param, gnu_param, false); /* If a parameter is a pointer, this function may modify memory through it and thus shouldn't be considered a const function. Also, the memory may be modified between two calls, so they can't be CSE'ed. The latter case also handles by-ref parameters. */ if (POINTER_TYPE_P (gnu_param_type) || TYPE_IS_FAT_POINTER_P (gnu_param_type)) const_flag = false; } if (copy_in_copy_out) { if (!gnu_cico_list) { tree gnu_new_ret_type = make_node (RECORD_TYPE); /* If this is a function, we also need a field for the return value to be placed. */ if (TREE_CODE (gnu_return_type) != VOID_TYPE) { gnu_field = create_field_decl (get_identifier ("RETVAL"), gnu_return_type, gnu_new_ret_type, NULL_TREE, NULL_TREE, 0, 0); Sloc_to_locus (Sloc (gnat_entity), &DECL_SOURCE_LOCATION (gnu_field)); gnu_field_list = gnu_field; gnu_cico_list = tree_cons (gnu_field, void_type_node, NULL_TREE); } gnu_return_type = gnu_new_ret_type; TYPE_NAME (gnu_return_type) = get_identifier ("RETURN"); /* Set a default alignment to speed up accesses. But we shouldn't increase the size of the structure too much, lest it doesn't fit in return registers anymore. */ TYPE_ALIGN (gnu_return_type) = get_mode_alignment (ptr_mode); } gnu_field = create_field_decl (gnu_param_name, gnu_param_type, gnu_return_type, NULL_TREE, NULL_TREE, 0, 0); Sloc_to_locus (Sloc (gnat_param), &DECL_SOURCE_LOCATION (gnu_field)); DECL_CHAIN (gnu_field) = gnu_field_list; gnu_field_list = gnu_field; gnu_cico_list = tree_cons (gnu_field, gnu_param, gnu_cico_list); } } if (gnu_cico_list) { /* If we have a CICO list but it has only one entry, we convert this function into a function that returns this object. */ if (list_length (gnu_cico_list) == 1) gnu_return_type = TREE_TYPE (TREE_PURPOSE (gnu_cico_list)); /* Do not finalize the return type if the subprogram is stubbed since structures are incomplete for the back-end. */ else if (Convention (gnat_entity) != Convention_Stubbed) { finish_record_type (gnu_return_type, nreverse (gnu_field_list), 0, false); /* Try to promote the mode of the return type if it is passed in registers, again to speed up accesses. */ if (TYPE_MODE (gnu_return_type) == BLKmode && !targetm.calls.return_in_memory (gnu_return_type, NULL_TREE)) { unsigned int size = TREE_INT_CST_LOW (TYPE_SIZE (gnu_return_type)); unsigned int i = BITS_PER_UNIT; machine_mode mode; while (i < size) i <<= 1; mode = mode_for_size (i, MODE_INT, 0); if (mode != BLKmode) { SET_TYPE_MODE (gnu_return_type, mode); TYPE_ALIGN (gnu_return_type) = GET_MODE_ALIGNMENT (mode); TYPE_SIZE (gnu_return_type) = bitsize_int (GET_MODE_BITSIZE (mode)); TYPE_SIZE_UNIT (gnu_return_type) = size_int (GET_MODE_SIZE (mode)); } } if (debug_info_p) rest_of_record_type_compilation (gnu_return_type); } } /* Deal with platform-specific calling conventions. */ if (Has_Stdcall_Convention (gnat_entity)) prepend_one_attribute (&attr_list, ATTR_MACHINE_ATTRIBUTE, get_identifier ("stdcall"), NULL_TREE, gnat_entity); else if (Has_Thiscall_Convention (gnat_entity)) prepend_one_attribute (&attr_list, ATTR_MACHINE_ATTRIBUTE, get_identifier ("thiscall"), NULL_TREE, gnat_entity); /* If we should request stack realignment for a foreign convention subprogram, do so. Note that this applies to task entry points in particular. */ if (FOREIGN_FORCE_REALIGN_STACK && Has_Foreign_Convention (gnat_entity)) prepend_one_attribute (&attr_list, ATTR_MACHINE_ATTRIBUTE, get_identifier ("force_align_arg_pointer"), NULL_TREE, gnat_entity); /* Deal with a pragma Linker_Section on a subprogram. */ if ((kind == E_Function || kind == E_Procedure) && Present (Linker_Section_Pragma (gnat_entity))) prepend_one_attribute_pragma (&attr_list, Linker_Section_Pragma (gnat_entity)); /* The lists have been built in reverse. */ gnu_param_list = nreverse (gnu_param_list); gnu_cico_list = nreverse (gnu_cico_list); if (kind == E_Function) Set_Mechanism (gnat_entity, return_unconstrained_p || return_by_direct_ref_p || return_by_invisi_ref_p ? By_Reference : By_Copy); gnu_type = create_subprog_type (gnu_return_type, gnu_param_list, gnu_cico_list, return_unconstrained_p, return_by_direct_ref_p, return_by_invisi_ref_p); /* A procedure (something that doesn't return anything) shouldn't be considered const since there would be no reason for calling such a subprogram. Note that procedures with Out (or In Out) parameters have already been converted into a function with a return type. Similarly, if the function returns an unconstrained type, then the function will allocate the return value on the secondary stack and thus calls to it cannot be CSE'ed, lest the stack be reclaimed. */ if (TREE_CODE (gnu_return_type) == VOID_TYPE || return_unconstrained_p) const_flag = false; if (const_flag || noreturn_flag) { const int quals = (const_flag ? TYPE_QUAL_CONST : 0) | (noreturn_flag ? TYPE_QUAL_VOLATILE : 0); gnu_type = change_qualified_type (gnu_type, quals); } /* If we have a builtin decl for that function, use it. Check if the profiles are compatible and warn if they are not. The checker is expected to post extra diagnostics in this case. */ if (gnu_builtin_decl) { intrin_binding_t inb; inb.gnat_entity = gnat_entity; inb.ada_fntype = gnu_type; inb.btin_fntype = TREE_TYPE (gnu_builtin_decl); if (!intrin_profiles_compatible_p (&inb)) post_error ("?profile of& doesn''t match the builtin it binds!", gnat_entity); gnu_decl = gnu_builtin_decl; gnu_type = TREE_TYPE (gnu_builtin_decl); break; } /* If there was no specified Interface_Name and the external and internal names of the subprogram are the same, only use the internal name to allow disambiguation of nested subprograms. */ if (No (Interface_Name (gnat_entity)) && gnu_ext_name == gnu_entity_name) gnu_ext_name = NULL_TREE; /* If we are defining the subprogram and it has an Address clause we must get the address expression from the saved GCC tree for the subprogram if it has a Freeze_Node. Otherwise, we elaborate the address expression here since the front-end has guaranteed in that case that the elaboration has no effects. If there is an Address clause and we are not defining the object, just make it a constant. */ if (Present (Address_Clause (gnat_entity))) { tree gnu_address = NULL_TREE; if (definition) gnu_address = (present_gnu_tree (gnat_entity) ? get_gnu_tree (gnat_entity) : gnat_to_gnu (Expression (Address_Clause (gnat_entity)))); save_gnu_tree (gnat_entity, NULL_TREE, false); /* Convert the type of the object to a reference type that can alias everything as per 13.3(19). */ gnu_type = build_reference_type_for_mode (gnu_type, ptr_mode, true); if (gnu_address) gnu_address = convert (gnu_type, gnu_address); gnu_decl = create_var_decl (gnu_entity_name, gnu_ext_name, gnu_type, gnu_address, false, Is_Public (gnat_entity), extern_flag, false, NULL, gnat_entity); DECL_BY_REF_P (gnu_decl) = 1; } else if (kind == E_Subprogram_Type) { process_attributes (&gnu_type, &attr_list, false, gnat_entity); gnu_decl = create_type_decl (gnu_entity_name, gnu_type, artificial_flag, debug_info_p, gnat_entity); } else { gnu_decl = create_subprog_decl (gnu_entity_name, gnu_ext_name, gnu_type, gnu_param_list, inline_status, public_flag, extern_flag, artificial_flag, attr_list, gnat_entity); /* This is unrelated to the stub built right above. */ DECL_STUBBED_P (gnu_decl) = Convention (gnat_entity) == Convention_Stubbed; } } break; case E_Incomplete_Type: case E_Incomplete_Subtype: case E_Private_Type: case E_Private_Subtype: case E_Limited_Private_Type: case E_Limited_Private_Subtype: case E_Record_Type_With_Private: case E_Record_Subtype_With_Private: { bool is_from_limited_with = (IN (kind, Incomplete_Kind) && From_Limited_With (gnat_entity)); /* Get the "full view" of this entity. If this is an incomplete entity from a limited with, treat its non-limited view as the full view. Otherwise, use either the full view or the underlying full view, whichever is present. This is used in all the tests below. */ Entity_Id full_view = is_from_limited_with ? Non_Limited_View (gnat_entity) : Present (Full_View (gnat_entity)) ? Full_View (gnat_entity) : IN (kind, Private_Kind) ? Underlying_Full_View (gnat_entity) : Empty; /* If this is an incomplete type with no full view, it must be a Taft Amendment type, in which case we return a dummy type. Otherwise, just get the type from its Etype. */ if (No (full_view)) { if (kind == E_Incomplete_Type) { gnu_type = make_dummy_type (gnat_entity); gnu_decl = TYPE_STUB_DECL (gnu_type); } else { gnu_decl = gnat_to_gnu_entity (Etype (gnat_entity), NULL_TREE, 0); maybe_present = true; } break; } /* If we already made a type for the full view, reuse it. */ else if (present_gnu_tree (full_view)) { gnu_decl = get_gnu_tree (full_view); break; } /* Otherwise, if we are not defining the type now, get the type from the full view. But always get the type from the full view for define on use types, since otherwise we won't see them. Likewise if this is a non-limited view not declared in the main unit, which can happen for incomplete formal types instantiated on a type coming from a limited_with clause. */ else if (!definition || (Is_Itype (full_view) && No (Freeze_Node (gnat_entity))) || (Is_Itype (gnat_entity) && No (Freeze_Node (full_view))) || (is_from_limited_with && !In_Extended_Main_Code_Unit (full_view))) { gnu_decl = gnat_to_gnu_entity (full_view, NULL_TREE, 0); maybe_present = true; break; } /* For incomplete types, make a dummy type entry which will be replaced later. Save it as the full declaration's type so we can do any needed updates when we see it. */ gnu_type = make_dummy_type (gnat_entity); gnu_decl = TYPE_STUB_DECL (gnu_type); if (Has_Completion_In_Body (gnat_entity)) DECL_TAFT_TYPE_P (gnu_decl) = 1; save_gnu_tree (full_view, gnu_decl, 0); break; } case E_Class_Wide_Type: /* Class-wide types are always transformed into their root type. */ gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0); maybe_present = true; break; case E_Task_Type: case E_Task_Subtype: case E_Protected_Type: case E_Protected_Subtype: /* Concurrent types are always transformed into their record type. */ if (type_annotate_only && No (gnat_equiv_type)) gnu_type = void_type_node; else gnu_decl = gnat_to_gnu_entity (gnat_equiv_type, NULL_TREE, 0); maybe_present = true; break; case E_Label: gnu_decl = create_label_decl (gnu_entity_name, gnat_entity); break; case E_Block: case E_Loop: /* Nothing at all to do here, so just return an ERROR_MARK and claim we've already saved it, so we don't try to. */ gnu_decl = error_mark_node; saved = true; break; case E_Abstract_State: /* This is a SPARK annotation that only reaches here when compiling in ASIS mode. */ gcc_assert (type_annotate_only); gnu_decl = error_mark_node; saved = true; break; default: gcc_unreachable (); } /* If we had a case where we evaluated another type and it might have defined this one, handle it here. */ if (maybe_present && present_gnu_tree (gnat_entity)) { gnu_decl = get_gnu_tree (gnat_entity); saved = true; } /* If we are processing a type and there is either no decl for it or we just made one, do some common processing for the type, such as handling alignment and possible padding. */ if (is_type && (!gnu_decl || this_made_decl)) { /* Process the attributes, if not already done. Note that the type is already defined so we cannot pass true for IN_PLACE here. */ process_attributes (&gnu_type, &attr_list, false, gnat_entity); /* Tell the middle-end that objects of tagged types are guaranteed to be properly aligned. This is necessary because conversions to the class-wide type are translated into conversions to the root type, which can be less aligned than some of its derived types. */ if (Is_Tagged_Type (gnat_entity) || Is_Class_Wide_Equivalent_Type (gnat_entity)) TYPE_ALIGN_OK (gnu_type) = 1; /* Record whether the type is passed by reference. */ if (!VOID_TYPE_P (gnu_type) && Is_By_Reference_Type (gnat_entity)) TYPE_BY_REFERENCE_P (gnu_type) = 1; /* ??? Don't set the size for a String_Literal since it is either confirming or we don't handle it properly (if the low bound is non-constant). */ if (!gnu_size && kind != E_String_Literal_Subtype) { Uint gnat_size = Known_Esize (gnat_entity) ? Esize (gnat_entity) : RM_Size (gnat_entity); gnu_size = validate_size (gnat_size, gnu_type, gnat_entity, TYPE_DECL, false, Has_Size_Clause (gnat_entity)); } /* If a size was specified, see if we can make a new type of that size by rearranging the type, for example from a fat to a thin pointer. */ if (gnu_size) { gnu_type = make_type_from_size (gnu_type, gnu_size, Has_Biased_Representation (gnat_entity)); if (operand_equal_p (TYPE_SIZE (gnu_type), gnu_size, 0) && operand_equal_p (rm_size (gnu_type), gnu_size, 0)) gnu_size = NULL_TREE; } /* If the alignment has not already been processed and this is not an unconstrained array type, see if an alignment is specified. If not, we pick a default alignment for atomic objects. */ if (align != 0 || TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE) ; else if (Known_Alignment (gnat_entity)) { align = validate_alignment (Alignment (gnat_entity), gnat_entity, TYPE_ALIGN (gnu_type)); /* Warn on suspiciously large alignments. This should catch errors about the (alignment,byte)/(size,bit) discrepancy. */ if (align > BIGGEST_ALIGNMENT && Has_Alignment_Clause (gnat_entity)) { tree size; /* If a size was specified, take it into account. Otherwise use the RM size for records or unions as the type size has already been adjusted to the alignment. */ if (gnu_size) size = gnu_size; else if (RECORD_OR_UNION_TYPE_P (gnu_type) && !TYPE_FAT_POINTER_P (gnu_type)) size = rm_size (gnu_type); else size = TYPE_SIZE (gnu_type); /* Consider an alignment as suspicious if the alignment/size ratio is greater or equal to the byte/bit ratio. */ if (tree_fits_uhwi_p (size) && align >= tree_to_uhwi (size) * BITS_PER_UNIT) post_error_ne ("?suspiciously large alignment specified for&", Expression (Alignment_Clause (gnat_entity)), gnat_entity); } } else if (Is_Atomic_Or_VFA (gnat_entity) && !gnu_size && tree_fits_uhwi_p (TYPE_SIZE (gnu_type)) && integer_pow2p (TYPE_SIZE (gnu_type))) align = MIN (BIGGEST_ALIGNMENT, tree_to_uhwi (TYPE_SIZE (gnu_type))); else if (Is_Atomic_Or_VFA (gnat_entity) && gnu_size && tree_fits_uhwi_p (gnu_size) && integer_pow2p (gnu_size)) align = MIN (BIGGEST_ALIGNMENT, tree_to_uhwi (gnu_size)); /* See if we need to pad the type. If we did, and made a record, the name of the new type may be changed. So get it back for us when we make the new TYPE_DECL below. */ if (gnu_size || align > 0) gnu_type = maybe_pad_type (gnu_type, gnu_size, align, gnat_entity, false, !gnu_decl, definition, false); if (TYPE_IS_PADDING_P (gnu_type)) gnu_entity_name = TYPE_IDENTIFIER (gnu_type); /* Now set the RM size of the type. We cannot do it before padding because we need to accept arbitrary RM sizes on integral types. */ set_rm_size (RM_Size (gnat_entity), gnu_type, gnat_entity); /* If we are at global level, GCC will have applied variable_size to the type, but that won't have done anything. So, if it's not a constant or self-referential, call elaborate_expression_1 to make a variable for the size rather than calculating it each time. Handle both the RM size and the actual size. */ if (global_bindings_p () && TYPE_SIZE (gnu_type) && !TREE_CONSTANT (TYPE_SIZE (gnu_type)) && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))) { tree size = TYPE_SIZE (gnu_type); TYPE_SIZE (gnu_type) = elaborate_expression_1 (size, gnat_entity, "SIZE", definition, false); /* ??? For now, store the size as a multiple of the alignment in bytes so that we can see the alignment from the tree. */ TYPE_SIZE_UNIT (gnu_type) = elaborate_expression_2 (TYPE_SIZE_UNIT (gnu_type), gnat_entity, "SIZE_A_UNIT", definition, false, TYPE_ALIGN (gnu_type)); /* ??? gnu_type may come from an existing type so the MULT_EXPR node may not be marked by the call to create_type_decl below. */ MARK_VISITED (TYPE_SIZE_UNIT (gnu_type)); if (TREE_CODE (gnu_type) == RECORD_TYPE) { tree variant_part = get_variant_part (gnu_type); tree ada_size = TYPE_ADA_SIZE (gnu_type); if (variant_part) { tree union_type = TREE_TYPE (variant_part); tree offset = DECL_FIELD_OFFSET (variant_part); /* If the position of the variant part is constant, subtract it from the size of the type of the parent to get the new size. This manual CSE reduces the data size. */ if (TREE_CODE (offset) == INTEGER_CST) { tree bitpos = DECL_FIELD_BIT_OFFSET (variant_part); TYPE_SIZE (union_type) = size_binop (MINUS_EXPR, TYPE_SIZE (gnu_type), bit_from_pos (offset, bitpos)); TYPE_SIZE_UNIT (union_type) = size_binop (MINUS_EXPR, TYPE_SIZE_UNIT (gnu_type), byte_from_pos (offset, bitpos)); } else { TYPE_SIZE (union_type) = elaborate_expression_1 (TYPE_SIZE (union_type), gnat_entity, "VSIZE", definition, false); /* ??? For now, store the size as a multiple of the alignment in bytes so that we can see the alignment from the tree. */ TYPE_SIZE_UNIT (union_type) = elaborate_expression_2 (TYPE_SIZE_UNIT (union_type), gnat_entity, "VSIZE_A_UNIT", definition, false, TYPE_ALIGN (union_type)); /* ??? For now, store the offset as a multiple of the alignment in bytes so that we can see the alignment from the tree. */ DECL_FIELD_OFFSET (variant_part) = elaborate_expression_2 (offset, gnat_entity, "VOFFSET", definition, false, DECL_OFFSET_ALIGN (variant_part)); } DECL_SIZE (variant_part) = TYPE_SIZE (union_type); DECL_SIZE_UNIT (variant_part) = TYPE_SIZE_UNIT (union_type); } if (operand_equal_p (ada_size, size, 0)) ada_size = TYPE_SIZE (gnu_type); else ada_size = elaborate_expression_1 (ada_size, gnat_entity, "RM_SIZE", definition, false); SET_TYPE_ADA_SIZE (gnu_type, ada_size); } } /* If this is a record type or subtype, call elaborate_expression_2 on any field position. Do this for both global and local types. Skip any fields that we haven't made trees for to avoid problems with class wide types. */ if (IN (kind, Record_Kind)) for (gnat_temp = First_Entity (gnat_entity); Present (gnat_temp); gnat_temp = Next_Entity (gnat_temp)) if (Ekind (gnat_temp) == E_Component && present_gnu_tree (gnat_temp)) { tree gnu_field = get_gnu_tree (gnat_temp); /* ??? For now, store the offset as a multiple of the alignment in bytes so that we can see the alignment from the tree. */ if (!CONTAINS_PLACEHOLDER_P (DECL_FIELD_OFFSET (gnu_field))) { DECL_FIELD_OFFSET (gnu_field) = elaborate_expression_2 (DECL_FIELD_OFFSET (gnu_field), gnat_temp, "OFFSET", definition, false, DECL_OFFSET_ALIGN (gnu_field)); /* ??? The context of gnu_field is not necessarily gnu_type so the MULT_EXPR node built above may not be marked by the call to create_type_decl below. */ if (global_bindings_p ()) MARK_VISITED (DECL_FIELD_OFFSET (gnu_field)); } } if (Is_Atomic_Or_VFA (gnat_entity)) check_ok_for_atomic_type (gnu_type, gnat_entity, false); /* If this is not an unconstrained array type, set some flags. */ if (TREE_CODE (gnu_type) != UNCONSTRAINED_ARRAY_TYPE) { if (Present (Alignment_Clause (gnat_entity))) TYPE_USER_ALIGN (gnu_type) = 1; if (Universal_Aliasing (gnat_entity)) TYPE_UNIVERSAL_ALIASING_P (gnu_type) = 1; /* If it is passed by reference, force BLKmode to ensure that objects of this type will always be put in memory. */ if (TYPE_MODE (gnu_type) != BLKmode && AGGREGATE_TYPE_P (gnu_type) && TYPE_BY_REFERENCE_P (gnu_type)) SET_TYPE_MODE (gnu_type, BLKmode); if (Treat_As_Volatile (gnat_entity)) { const int quals = TYPE_QUAL_VOLATILE | (Is_Atomic_Or_VFA (gnat_entity) ? TYPE_QUAL_ATOMIC : 0); gnu_type = change_qualified_type (gnu_type, quals); } } if (!gnu_decl) gnu_decl = create_type_decl (gnu_entity_name, gnu_type, !Comes_From_Source (gnat_entity), debug_info_p, gnat_entity); else { TREE_TYPE (gnu_decl) = gnu_type; TYPE_STUB_DECL (gnu_type) = gnu_decl; } } if (is_type && !TYPE_IS_DUMMY_P (TREE_TYPE (gnu_decl))) { gnu_type = TREE_TYPE (gnu_decl); /* If this is a derived type, relate its alias set to that of its parent to avoid troubles when a call to an inherited primitive is inlined in a context where a derived object is accessed. The inlined code works on the parent view so the resulting code may access the same object using both the parent and the derived alias sets, which thus have to conflict. As the same issue arises with component references, the parent alias set also has to conflict with composite types enclosing derived components. For instance, if we have: type D is new T; type R is record Component : D; end record; we want T to conflict with both D and R, in addition to R being a superset of D by record/component construction. One way to achieve this is to perform an alias set copy from the parent to the derived type. This is not quite appropriate, though, as we don't want separate derived types to conflict with each other: type I1 is new Integer; type I2 is new Integer; We want I1 and I2 to both conflict with Integer but we do not want I1 to conflict with I2, and an alias set copy on derivation would have that effect. The option chosen is to make the alias set of the derived type a superset of that of its parent type. It trivially fulfills the simple requirement for the Integer derivation example above, and the component case as well by superset transitivity: superset superset R ----------> D ----------> T However, for composite types, conversions between derived types are translated into VIEW_CONVERT_EXPRs so a sequence like: type Comp1 is new Comp; type Comp2 is new Comp; procedure Proc (C : Comp1); C : Comp2; Proc (Comp1 (C)); is translated into: C : Comp2; Proc ((Comp1 &) &VIEW_CONVERT_EXPR (C)); and gimplified into: C : Comp2; Comp1 *C.0; C.0 = (Comp1 *) &C; Proc (C.0); i.e. generates code involving type punning. Therefore, Comp1 needs to conflict with Comp2 and an alias set copy is required. The language rules ensure the parent type is already frozen here. */ if (kind != E_Subprogram_Type && Is_Derived_Type (gnat_entity) && !type_annotate_only) { Entity_Id gnat_parent_type = Underlying_Type (Etype (gnat_entity)); /* For constrained packed array subtypes, the implementation type is used instead of the nominal type. */ if (kind == E_Array_Subtype && Is_Constrained (gnat_entity) && Present (Packed_Array_Impl_Type (gnat_parent_type))) gnat_parent_type = Packed_Array_Impl_Type (gnat_parent_type); relate_alias_sets (gnu_type, gnat_to_gnu_type (gnat_parent_type), Is_Composite_Type (gnat_entity) ? ALIAS_SET_COPY : ALIAS_SET_SUPERSET); } /* Back-annotate the Alignment of the type if not already in the tree. Likewise for sizes. */ if (Unknown_Alignment (gnat_entity)) { unsigned int double_align, align; bool is_capped_double, align_clause; /* If the default alignment of "double" or larger scalar types is specifically capped and this is not an array with an alignment clause on the component type, return the cap. */ if ((double_align = double_float_alignment) > 0) is_capped_double = is_double_float_or_array (gnat_entity, &align_clause); else if ((double_align = double_scalar_alignment) > 0) is_capped_double = is_double_scalar_or_array (gnat_entity, &align_clause); else is_capped_double = align_clause = false; if (is_capped_double && !align_clause) align = double_align; else align = TYPE_ALIGN (gnu_type) / BITS_PER_UNIT; Set_Alignment (gnat_entity, UI_From_Int (align)); } if (Unknown_Esize (gnat_entity) && TYPE_SIZE (gnu_type)) { tree gnu_size = TYPE_SIZE (gnu_type); /* If the size is self-referential, annotate the maximum value. */ if (CONTAINS_PLACEHOLDER_P (gnu_size)) gnu_size = max_size (gnu_size, true); /* If we are just annotating types and the type is tagged, the tag and the parent components are not generated by the front-end so sizes must be adjusted if there is no representation clause. */ if (type_annotate_only && Is_Tagged_Type (gnat_entity) && !VOID_TYPE_P (gnu_type) && (!TYPE_FIELDS (gnu_type) || integer_zerop (bit_position (TYPE_FIELDS (gnu_type))))) { tree pointer_size = bitsize_int (POINTER_SIZE), offset; Uint uint_size; if (Is_Derived_Type (gnat_entity)) { Entity_Id gnat_parent = Etype (Base_Type (gnat_entity)); offset = UI_To_gnu (Esize (gnat_parent), bitsizetype); Set_Alignment (gnat_entity, Alignment (gnat_parent)); } else offset = pointer_size; if (TYPE_FIELDS (gnu_type)) offset = round_up (offset, DECL_ALIGN (TYPE_FIELDS (gnu_type))); gnu_size = size_binop (PLUS_EXPR, gnu_size, offset); gnu_size = round_up (gnu_size, POINTER_SIZE); uint_size = annotate_value (gnu_size); Set_Esize (gnat_entity, uint_size); Set_RM_Size (gnat_entity, uint_size); } else Set_Esize (gnat_entity, annotate_value (gnu_size)); } if (Unknown_RM_Size (gnat_entity) && rm_size (gnu_type)) Set_RM_Size (gnat_entity, annotate_value (rm_size (gnu_type))); } /* If we really have a ..._DECL node, set a couple of flags on it. But we cannot do so if we are reusing the ..._DECL node made for an equivalent type or an alias or a renamed object as the predicates don't apply to it but to GNAT_ENTITY. */ if (DECL_P (gnu_decl) && !(is_type && gnat_equiv_type != gnat_entity) && !Present (Alias (gnat_entity)) && !(Present (Renamed_Object (gnat_entity)) && saved)) { if (!Comes_From_Source (gnat_entity)) DECL_ARTIFICIAL (gnu_decl) = 1; if (!debug_info_p) DECL_IGNORED_P (gnu_decl) = 1; } /* If we haven't already, associate the ..._DECL node that we just made with the input GNAT entity node. */ if (!saved) save_gnu_tree (gnat_entity, gnu_decl, false); /* Now we are sure gnat_entity has a corresponding ..._DECL node, eliminate as many deferred computations as possible. */ process_deferred_decl_context (false); /* If this is an enumeration or floating-point type, we were not able to set the bounds since they refer to the type. These are always static. */ if ((kind == E_Enumeration_Type && Present (First_Literal (gnat_entity))) || (kind == E_Floating_Point_Type)) { tree gnu_scalar_type = gnu_type; tree gnu_low_bound, gnu_high_bound; /* If this is a padded type, we need to use the underlying type. */ if (TYPE_IS_PADDING_P (gnu_scalar_type)) gnu_scalar_type = TREE_TYPE (TYPE_FIELDS (gnu_scalar_type)); /* If this is a floating point type and we haven't set a floating point type yet, use this in the evaluation of the bounds. */ if (!longest_float_type_node && kind == E_Floating_Point_Type) longest_float_type_node = gnu_scalar_type; gnu_low_bound = gnat_to_gnu (Type_Low_Bound (gnat_entity)); gnu_high_bound = gnat_to_gnu (Type_High_Bound (gnat_entity)); if (kind == E_Enumeration_Type) { /* Enumeration types have specific RM bounds. */ SET_TYPE_RM_MIN_VALUE (gnu_scalar_type, gnu_low_bound); SET_TYPE_RM_MAX_VALUE (gnu_scalar_type, gnu_high_bound); } else { /* Floating-point types don't have specific RM bounds. */ TYPE_GCC_MIN_VALUE (gnu_scalar_type) = gnu_low_bound; TYPE_GCC_MAX_VALUE (gnu_scalar_type) = gnu_high_bound; } } /* If we deferred processing of incomplete types, re-enable it. If there were no other disables and we have deferred types to process, do so. */ if (this_deferred && --defer_incomplete_level == 0 && defer_incomplete_list) { struct incomplete *p, *next; /* We are back to level 0 for the deferring of incomplete types. But processing these incomplete types below may itself require deferring, so preserve what we have and restart from scratch. */ p = defer_incomplete_list; defer_incomplete_list = NULL; for (; p; p = next) { next = p->next; if (p->old_type) update_pointer_to (TYPE_MAIN_VARIANT (p->old_type), gnat_to_gnu_type (p->full_type)); free (p); } } /* If we are not defining this type, see if it's on one of the lists of incomplete types. If so, handle the list entry now. */ if (is_type && !definition) { struct incomplete *p; for (p = defer_incomplete_list; p; p = p->next) if (p->old_type && p->full_type == gnat_entity) { update_pointer_to (TYPE_MAIN_VARIANT (p->old_type), TREE_TYPE (gnu_decl)); p->old_type = NULL_TREE; } for (p = defer_limited_with; p; p = p->next) if (p->old_type && Non_Limited_View (p->full_type) == gnat_entity) { update_pointer_to (TYPE_MAIN_VARIANT (p->old_type), TREE_TYPE (gnu_decl)); p->old_type = NULL_TREE; } } if (this_global) force_global--; /* If this is a packed array type whose original array type is itself an Itype without freeze node, make sure the latter is processed. */ if (Is_Packed_Array_Impl_Type (gnat_entity) && Is_Itype (Original_Array_Type (gnat_entity)) && No (Freeze_Node (Original_Array_Type (gnat_entity))) && !present_gnu_tree (Original_Array_Type (gnat_entity))) gnat_to_gnu_entity (Original_Array_Type (gnat_entity), NULL_TREE, 0); return gnu_decl; } /* Similar, but if the returned value is a COMPONENT_REF, return the FIELD_DECL. */ tree gnat_to_gnu_field_decl (Entity_Id gnat_entity) { tree gnu_field = gnat_to_gnu_entity (gnat_entity, NULL_TREE, 0); if (TREE_CODE (gnu_field) == COMPONENT_REF) gnu_field = TREE_OPERAND (gnu_field, 1); return gnu_field; } /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type. Return the GCC type corresponding to that entity. */ tree gnat_to_gnu_type (Entity_Id gnat_entity) { tree gnu_decl; /* The back end never attempts to annotate generic types. */ if (Is_Generic_Type (gnat_entity) && type_annotate_only) return void_type_node; gnu_decl = gnat_to_gnu_entity (gnat_entity, NULL_TREE, 0); gcc_assert (TREE_CODE (gnu_decl) == TYPE_DECL); return TREE_TYPE (gnu_decl); } /* Similar, but GNAT_ENTITY is assumed to refer to a GNAT type. Return the unpadded version of the GCC type corresponding to that entity. */ tree get_unpadded_type (Entity_Id gnat_entity) { tree type = gnat_to_gnu_type (gnat_entity); if (TYPE_IS_PADDING_P (type)) type = TREE_TYPE (TYPE_FIELDS (type)); return type; } /* Return the DECL associated with the public subprogram GNAT_ENTITY but whose type has been changed to that of the parameterless procedure, except if an alias is already present, in which case it is returned instead. */ tree get_minimal_subprog_decl (Entity_Id gnat_entity) { tree gnu_entity_name, gnu_ext_name; struct attrib *attr_list = NULL; /* See the E_Function/E_Procedure case of gnat_to_gnu_entity for the model of the handling applied here. */ while (Present (Alias (gnat_entity))) { gnat_entity = Alias (gnat_entity); if (present_gnu_tree (gnat_entity)) return get_gnu_tree (gnat_entity); } gnu_entity_name = get_entity_name (gnat_entity); gnu_ext_name = create_concat_name (gnat_entity, NULL); if (Has_Stdcall_Convention (gnat_entity)) prepend_one_attribute (&attr_list, ATTR_MACHINE_ATTRIBUTE, get_identifier ("stdcall"), NULL_TREE, gnat_entity); else if (Has_Thiscall_Convention (gnat_entity)) prepend_one_attribute (&attr_list, ATTR_MACHINE_ATTRIBUTE, get_identifier ("thiscall"), NULL_TREE, gnat_entity); if (No (Interface_Name (gnat_entity)) && gnu_ext_name == gnu_entity_name) gnu_ext_name = NULL_TREE; return create_subprog_decl (gnu_entity_name, gnu_ext_name, void_ftype, NULL_TREE, is_disabled, true, true, true, attr_list, gnat_entity); } /* Return whether the E_Subprogram_Type/E_Function/E_Procedure GNAT_ENTITY is a C++ imported method or equivalent. We use the predicate on 32-bit x86/Windows to find out whether we need to use the "thiscall" calling convention for GNAT_ENTITY. This convention is used for C++ methods (functions with METHOD_TYPE) by the back-end. */ bool is_cplusplus_method (Entity_Id gnat_entity) { if (Convention (gnat_entity) != Convention_CPP) return false; /* This is the main case: C++ method imported as a primitive operation. Note that a C++ class with no virtual functions can be imported as a limited record type so the operation is not necessarily dispatching. */ if (Is_Primitive (gnat_entity)) return true; /* A thunk needs to be handled like its associated primitive operation. */ if (Is_Subprogram (gnat_entity) && Is_Thunk (gnat_entity)) return true; /* A constructor is a method on the C++ side. */ if (Is_Constructor (gnat_entity)) return true; /* This is set on the E_Subprogram_Type built for a dispatching call. */ if (Is_Dispatch_Table_Entity (gnat_entity)) return true; return false; } /* Finalize the processing of From_Limited_With incomplete types. */ void finalize_from_limited_with (void) { struct incomplete *p, *next; p = defer_limited_with; defer_limited_with = NULL; for (; p; p = next) { next = p->next; if (p->old_type) update_pointer_to (TYPE_MAIN_VARIANT (p->old_type), gnat_to_gnu_type (p->full_type)); free (p); } } /* Return the equivalent type to be used for GNAT_ENTITY, if it's a kind of type (such E_Task_Type) that has a different type which Gigi uses for its representation. If the type does not have a special type for its representation, return GNAT_ENTITY. If a type is supposed to exist, but does not, abort unless annotating types, in which case return Empty. If GNAT_ENTITY is Empty, return Empty. */ Entity_Id Gigi_Equivalent_Type (Entity_Id gnat_entity) { Entity_Id gnat_equiv = gnat_entity; if (No (gnat_entity)) return gnat_entity; switch (Ekind (gnat_entity)) { case E_Class_Wide_Subtype: if (Present (Equivalent_Type (gnat_entity))) gnat_equiv = Equivalent_Type (gnat_entity); break; case E_Access_Protected_Subprogram_Type: case E_Anonymous_Access_Protected_Subprogram_Type: gnat_equiv = Equivalent_Type (gnat_entity); break; case E_Class_Wide_Type: gnat_equiv = Root_Type (gnat_entity); break; case E_Task_Type: case E_Task_Subtype: case E_Protected_Type: case E_Protected_Subtype: gnat_equiv = Corresponding_Record_Type (gnat_entity); break; default: break; } gcc_assert (Present (gnat_equiv) || type_annotate_only); return gnat_equiv; } /* Return a GCC tree for a type corresponding to the component type of the array type or subtype GNAT_ARRAY. DEFINITION is true if this component is for an array being defined. DEBUG_INFO_P is true if we need to write debug information for other types that we may create in the process. */ static tree gnat_to_gnu_component_type (Entity_Id gnat_array, bool definition, bool debug_info_p) { const Entity_Id gnat_type = Component_Type (gnat_array); tree gnu_type = gnat_to_gnu_type (gnat_type); tree gnu_comp_size; /* Try to get a smaller form of the component if needed. */ if ((Is_Packed (gnat_array) || Has_Component_Size_Clause (gnat_array)) && !Is_Bit_Packed_Array (gnat_array) && !Has_Aliased_Components (gnat_array) && !Strict_Alignment (gnat_type) && RECORD_OR_UNION_TYPE_P (gnu_type) && !TYPE_FAT_POINTER_P (gnu_type) && tree_fits_uhwi_p (TYPE_SIZE (gnu_type))) gnu_type = make_packable_type (gnu_type, false); if (Has_Atomic_Components (gnat_array)) check_ok_for_atomic_type (gnu_type, gnat_array, true); /* Get and validate any specified Component_Size. */ gnu_comp_size = validate_size (Component_Size (gnat_array), gnu_type, gnat_array, Is_Bit_Packed_Array (gnat_array) ? TYPE_DECL : VAR_DECL, true, Has_Component_Size_Clause (gnat_array)); /* If the array has aliased components and the component size can be zero, force at least unit size to ensure that the components have distinct addresses. */ if (!gnu_comp_size && Has_Aliased_Components (gnat_array) && (integer_zerop (TYPE_SIZE (gnu_type)) || (TREE_CODE (gnu_type) == ARRAY_TYPE && !TREE_CONSTANT (TYPE_SIZE (gnu_type))))) gnu_comp_size = size_binop (MAX_EXPR, TYPE_SIZE (gnu_type), bitsize_unit_node); /* If the component type is a RECORD_TYPE that has a self-referential size, then use the maximum size for the component size. */ if (!gnu_comp_size && TREE_CODE (gnu_type) == RECORD_TYPE && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))) gnu_comp_size = max_size (TYPE_SIZE (gnu_type), true); /* Honor the component size. This is not needed for bit-packed arrays. */ if (gnu_comp_size && !Is_Bit_Packed_Array (gnat_array)) { tree orig_type = gnu_type; unsigned int max_align; /* If an alignment is specified, use it as a cap on the component type so that it can be honored for the whole type. But ignore it for the original type of packed array types. */ if (No (Packed_Array_Impl_Type (gnat_array)) && Known_Alignment (gnat_array)) max_align = validate_alignment (Alignment (gnat_array), gnat_array, 0); else max_align = 0; gnu_type = make_type_from_size (gnu_type, gnu_comp_size, false); if (max_align > 0 && TYPE_ALIGN (gnu_type) > max_align) gnu_type = orig_type; else orig_type = gnu_type; gnu_type = maybe_pad_type (gnu_type, gnu_comp_size, 0, gnat_array, true, false, definition, true); /* If a padding record was made, declare it now since it will never be declared otherwise. This is necessary to ensure that its subtrees are properly marked. */ if (gnu_type != orig_type && !DECL_P (TYPE_NAME (gnu_type))) create_type_decl (TYPE_NAME (gnu_type), gnu_type, true, debug_info_p, gnat_array); } if (Has_Volatile_Components (gnat_array)) { const int quals = TYPE_QUAL_VOLATILE | (Has_Atomic_Components (gnat_array) ? TYPE_QUAL_ATOMIC : 0); gnu_type = change_qualified_type (gnu_type, quals); } return gnu_type; } /* Return a GCC tree for a parameter corresponding to GNAT_PARAM and using MECH as its passing mechanism, to be placed in the parameter list built for GNAT_SUBPROG. Assume a foreign convention for the latter if FOREIGN is true. Also set CICO to true if the parameter must use the copy-in copy-out implementation mechanism. The returned tree is a PARM_DECL, except for those cases where no parameter needs to be actually passed to the subprogram; the type of this "shadow" parameter is then returned instead. */ static tree gnat_to_gnu_param (Entity_Id gnat_param, Mechanism_Type mech, Entity_Id gnat_subprog, bool foreign, bool *cico) { tree gnu_param_name = get_entity_name (gnat_param); tree gnu_param_type = gnat_to_gnu_type (Etype (gnat_param)); bool in_param = (Ekind (gnat_param) == E_In_Parameter); /* The parameter can be indirectly modified if its address is taken. */ bool ro_param = in_param && !Address_Taken (gnat_param); bool by_return = false, by_component_ptr = false; bool by_ref = false; tree gnu_param; /* Copy-return is used only for the first parameter of a valued procedure. It's a copy mechanism for which a parameter is never allocated. */ if (mech == By_Copy_Return) { gcc_assert (Ekind (gnat_param) == E_Out_Parameter); mech = By_Copy; by_return = true; } /* If this is either a foreign function or if the underlying type won't be passed by reference and is as aligned as the original type, strip off possible padding type. */ if (TYPE_IS_PADDING_P (gnu_param_type)) { tree unpadded_type = TREE_TYPE (TYPE_FIELDS (gnu_param_type)); if (foreign || (!must_pass_by_ref (unpadded_type) && mech != By_Reference && (mech == By_Copy || !default_pass_by_ref (unpadded_type)) && TYPE_ALIGN (unpadded_type) >= TYPE_ALIGN (gnu_param_type))) gnu_param_type = unpadded_type; } /* If this is a read-only parameter, make a variant of the type that is read-only. ??? However, if this is an unconstrained array, that type can be very complex, so skip it for now. Likewise for any other self-referential type. */ if (ro_param && TREE_CODE (gnu_param_type) != UNCONSTRAINED_ARRAY_TYPE && !CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_param_type))) gnu_param_type = change_qualified_type (gnu_param_type, TYPE_QUAL_CONST); /* For foreign conventions, pass arrays as pointers to the element type. First check for unconstrained array and get the underlying array. */ if (foreign && TREE_CODE (gnu_param_type) == UNCONSTRAINED_ARRAY_TYPE) gnu_param_type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_param_type)))); /* For GCC builtins, pass Address integer types as (void *) */ if (Convention (gnat_subprog) == Convention_Intrinsic && Present (Interface_Name (gnat_subprog)) && Is_Descendent_Of_Address (Etype (gnat_param))) gnu_param_type = ptr_type_node; /* Arrays are passed as pointers to element type for foreign conventions. */ if (foreign && mech != By_Copy && TREE_CODE (gnu_param_type) == ARRAY_TYPE) { /* Strip off any multi-dimensional entries, then strip off the last array to get the component type. */ while (TREE_CODE (TREE_TYPE (gnu_param_type)) == ARRAY_TYPE && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_param_type))) gnu_param_type = TREE_TYPE (gnu_param_type); by_component_ptr = true; gnu_param_type = TREE_TYPE (gnu_param_type); if (ro_param) gnu_param_type = change_qualified_type (gnu_param_type, TYPE_QUAL_CONST); gnu_param_type = build_pointer_type (gnu_param_type); } /* Fat pointers are passed as thin pointers for foreign conventions. */ else if (foreign && TYPE_IS_FAT_POINTER_P (gnu_param_type)) gnu_param_type = make_type_from_size (gnu_param_type, size_int (POINTER_SIZE), 0); /* If we must pass or were requested to pass by reference, do so. If we were requested to pass by copy, do so. Otherwise, for foreign conventions, pass In Out or Out parameters or aggregates by reference. For COBOL and Fortran, pass all integer and FP types that way too. For Convention Ada, use the standard Ada default. */ else if (must_pass_by_ref (gnu_param_type) || mech == By_Reference || (mech != By_Copy && ((foreign && (!in_param || AGGREGATE_TYPE_P (gnu_param_type))) || (foreign && (Convention (gnat_subprog) == Convention_Fortran || Convention (gnat_subprog) == Convention_COBOL) && (INTEGRAL_TYPE_P (gnu_param_type) || FLOAT_TYPE_P (gnu_param_type))) || (!foreign && default_pass_by_ref (gnu_param_type))))) { /* We take advantage of 6.2(12) by considering that references built for parameters whose type isn't by-ref and for which the mechanism hasn't been forced to by-ref are restrict-qualified in the C sense. */ bool restrict_p = !TYPE_IS_BY_REFERENCE_P (gnu_param_type) && mech != By_Reference; gnu_param_type = build_reference_type (gnu_param_type); if (restrict_p) gnu_param_type = change_qualified_type (gnu_param_type, TYPE_QUAL_RESTRICT); by_ref = true; } /* Pass In Out or Out parameters using copy-in copy-out mechanism. */ else if (!in_param) *cico = true; if (mech == By_Copy && (by_ref || by_component_ptr)) post_error ("?cannot pass & by copy", gnat_param); /* If this is an Out parameter that isn't passed by reference and isn't a pointer or aggregate, we don't make a PARM_DECL for it. Instead, it will be a VAR_DECL created when we process the procedure, so just return its type. For the special parameter of a valued procedure, never pass it in. An exception is made to cover the RM-6.4.1 rule requiring "by copy" Out parameters with discriminants or implicit initial values to be handled like In Out parameters. These type are normally built as aggregates, hence passed by reference, except for some packed arrays which end up encoded in special integer types. Note that scalars can be given implicit initial values using the Default_Value aspect. The exception we need to make is then for packed arrays of records with discriminants or implicit initial values. We have no light/easy way to check for the latter case, so we merely check for packed arrays of records. This may lead to useless copy-in operations, but in very rare cases only, as these would be exceptions in a set of already exceptional situations. */ if (Ekind (gnat_param) == E_Out_Parameter && !by_ref && (by_return || (!POINTER_TYPE_P (gnu_param_type) && !AGGREGATE_TYPE_P (gnu_param_type) && !Has_Default_Aspect (Etype (gnat_param)))) && !(Is_Array_Type (Etype (gnat_param)) && Is_Packed (Etype (gnat_param)) && Is_Composite_Type (Component_Type (Etype (gnat_param))))) return gnu_param_type; gnu_param = create_param_decl (gnu_param_name, gnu_param_type, ro_param || by_ref || by_component_ptr); DECL_BY_REF_P (gnu_param) = by_ref; DECL_BY_COMPONENT_PTR_P (gnu_param) = by_component_ptr; DECL_POINTS_TO_READONLY_P (gnu_param) = (ro_param && (by_ref || by_component_ptr)); DECL_CAN_NEVER_BE_NULL_P (gnu_param) = Can_Never_Be_Null (gnat_param); /* If no Mechanism was specified, indicate what we're using, then back-annotate it. */ if (mech == Default) mech = (by_ref || by_component_ptr) ? By_Reference : By_Copy; Set_Mechanism (gnat_param, mech); return gnu_param; } /* Return true if GNAT_ENTITY is an incomplete entity coming from a limited with of the main unit and whose full view has not been elaborated yet. */ static bool is_from_limited_with_of_main (Entity_Id gnat_entity) { /* Class-wide types are always transformed into their root type. */ if (Ekind (gnat_entity) == E_Class_Wide_Type) gnat_entity = Root_Type (gnat_entity); if (IN (Ekind (gnat_entity), Incomplete_Kind) && From_Limited_With (gnat_entity)) { Entity_Id gnat_full_view = Non_Limited_View (gnat_entity); if (present_gnu_tree (gnat_full_view)) return false; return In_Extended_Main_Code_Unit (gnat_full_view); } return false; } /* Like build_qualified_type, but TYPE_QUALS is added to the existing qualifiers on TYPE. */ static tree change_qualified_type (tree type, int type_quals) { return build_qualified_type (type, TYPE_QUALS (type) | type_quals); } /* Return true if DISCR1 and DISCR2 represent the same discriminant. */ static bool same_discriminant_p (Entity_Id discr1, Entity_Id discr2) { while (Present (Corresponding_Discriminant (discr1))) discr1 = Corresponding_Discriminant (discr1); while (Present (Corresponding_Discriminant (discr2))) discr2 = Corresponding_Discriminant (discr2); return Original_Record_Component (discr1) == Original_Record_Component (discr2); } /* Return true if the array type GNU_TYPE, which represents a dimension of GNAT_TYPE, has a non-aliased component in the back-end sense. */ static bool array_type_has_nonaliased_component (tree gnu_type, Entity_Id gnat_type) { /* If the array type is not the innermost dimension of the GNAT type, then it has a non-aliased component. */ if (TREE_CODE (TREE_TYPE (gnu_type)) == ARRAY_TYPE && TYPE_MULTI_ARRAY_P (TREE_TYPE (gnu_type))) return true; /* If the array type has an aliased component in the front-end sense, then it also has an aliased component in the back-end sense. */ if (Has_Aliased_Components (gnat_type)) return false; /* If this is a derived type, then it has a non-aliased component if and only if its parent type also has one. */ if (Is_Derived_Type (gnat_type)) { tree gnu_parent_type = gnat_to_gnu_type (Etype (gnat_type)); int index; if (TREE_CODE (gnu_parent_type) == UNCONSTRAINED_ARRAY_TYPE) gnu_parent_type = TREE_TYPE (TREE_TYPE (TYPE_FIELDS (TREE_TYPE (gnu_parent_type)))); for (index = Number_Dimensions (gnat_type) - 1; index > 0; index--) gnu_parent_type = TREE_TYPE (gnu_parent_type); return TYPE_NONALIASED_COMPONENT (gnu_parent_type); } /* Otherwise, rely exclusively on properties of the element type. */ return type_for_nonaliased_component_p (TREE_TYPE (gnu_type)); } /* Return true if GNAT_ADDRESS is a value known at compile-time. */ static bool compile_time_known_address_p (Node_Id gnat_address) { /* Catch System'To_Address. */ if (Nkind (gnat_address) == N_Unchecked_Type_Conversion) gnat_address = Expression (gnat_address); return Compile_Time_Known_Value (gnat_address); } /* Return true if GNAT_RANGE, a N_Range node, cannot be superflat, i.e. if the inequality HB >= LB-1 is true. LB and HB are the low and high bounds. */ static bool cannot_be_superflat (Node_Id gnat_range) { Node_Id gnat_lb = Low_Bound (gnat_range), gnat_hb = High_Bound (gnat_range); Node_Id scalar_range; tree gnu_lb, gnu_hb, gnu_lb_minus_one; /* If the low bound is not constant, try to find an upper bound. */ while (Nkind (gnat_lb) != N_Integer_Literal && (Ekind (Etype (gnat_lb)) == E_Signed_Integer_Subtype || Ekind (Etype (gnat_lb)) == E_Modular_Integer_Subtype) && (scalar_range = Scalar_Range (Etype (gnat_lb))) && (Nkind (scalar_range) == N_Signed_Integer_Type_Definition || Nkind (scalar_range) == N_Range)) gnat_lb = High_Bound (scalar_range); /* If the high bound is not constant, try to find a lower bound. */ while (Nkind (gnat_hb) != N_Integer_Literal && (Ekind (Etype (gnat_hb)) == E_Signed_Integer_Subtype || Ekind (Etype (gnat_hb)) == E_Modular_Integer_Subtype) && (scalar_range = Scalar_Range (Etype (gnat_hb))) && (Nkind (scalar_range) == N_Signed_Integer_Type_Definition || Nkind (scalar_range) == N_Range)) gnat_hb = Low_Bound (scalar_range); /* If we have failed to find constant bounds, punt. */ if (Nkind (gnat_lb) != N_Integer_Literal || Nkind (gnat_hb) != N_Integer_Literal) return false; /* We need at least a signed 64-bit type to catch most cases. */ gnu_lb = UI_To_gnu (Intval (gnat_lb), sbitsizetype); gnu_hb = UI_To_gnu (Intval (gnat_hb), sbitsizetype); if (TREE_OVERFLOW (gnu_lb) || TREE_OVERFLOW (gnu_hb)) return false; /* If the low bound is the smallest integer, nothing can be smaller. */ gnu_lb_minus_one = size_binop (MINUS_EXPR, gnu_lb, sbitsize_one_node); if (TREE_OVERFLOW (gnu_lb_minus_one)) return true; return !tree_int_cst_lt (gnu_hb, gnu_lb_minus_one); } /* Return true if GNU_EXPR is (essentially) the address of a CONSTRUCTOR. */ static bool constructor_address_p (tree gnu_expr) { while (TREE_CODE (gnu_expr) == NOP_EXPR || TREE_CODE (gnu_expr) == CONVERT_EXPR || TREE_CODE (gnu_expr) == NON_LVALUE_EXPR) gnu_expr = TREE_OPERAND (gnu_expr, 0); return (TREE_CODE (gnu_expr) == ADDR_EXPR && TREE_CODE (TREE_OPERAND (gnu_expr, 0)) == CONSTRUCTOR); } /* Return true if the size in units represented by GNU_SIZE can be handled by an allocation. If STATIC_P is true, consider only what can be done with a static allocation. */ static bool allocatable_size_p (tree gnu_size, bool static_p) { /* We can allocate a fixed size if it is a valid for the middle-end. */ if (TREE_CODE (gnu_size) == INTEGER_CST) return valid_constant_size_p (gnu_size); /* We can allocate a variable size if this isn't a static allocation. */ else return !static_p; } /* Return true if GNU_EXPR needs a conversion to GNU_TYPE when used as the initial value of an object of GNU_TYPE. */ static bool initial_value_needs_conversion (tree gnu_type, tree gnu_expr) { /* Do not convert if the object's type is unconstrained because this would generate useless evaluations of the CONSTRUCTOR to compute the size. */ if (TREE_CODE (gnu_type) == UNCONSTRAINED_ARRAY_TYPE || CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_type))) return false; /* Do not convert if the object's type is a padding record whose field is of self-referential size because we want to copy only the actual data. */ if (type_is_padding_self_referential (gnu_type)) return false; /* Do not convert a call to a function that returns with variable size since we want to use the return slot optimization in this case. */ if (TREE_CODE (gnu_expr) == CALL_EXPR && return_type_with_variable_size_p (TREE_TYPE (gnu_expr))) return false; /* Do not convert to a record type with a variant part from a record type without one, to keep the object simpler. */ if (TREE_CODE (gnu_type) == RECORD_TYPE && TREE_CODE (TREE_TYPE (gnu_expr)) == RECORD_TYPE && get_variant_part (gnu_type) != NULL_TREE && get_variant_part (TREE_TYPE (gnu_expr)) == NULL_TREE) return false; /* In all the other cases, convert the expression to the object's type. */ return true; } /* Given GNAT_ENTITY, elaborate all expressions that are required to be elaborated at the point of its definition, but do nothing else. */ void elaborate_entity (Entity_Id gnat_entity) { switch (Ekind (gnat_entity)) { case E_Signed_Integer_Subtype: case E_Modular_Integer_Subtype: case E_Enumeration_Subtype: case E_Ordinary_Fixed_Point_Subtype: case E_Decimal_Fixed_Point_Subtype: case E_Floating_Point_Subtype: { Node_Id gnat_lb = Type_Low_Bound (gnat_entity); Node_Id gnat_hb = Type_High_Bound (gnat_entity); /* ??? Tests to avoid Constraint_Error in static expressions are needed until after the front stops generating bogus conversions on bounds of real types. */ if (!Raises_Constraint_Error (gnat_lb)) elaborate_expression (gnat_lb, gnat_entity, "L", true, false, Needs_Debug_Info (gnat_entity)); if (!Raises_Constraint_Error (gnat_hb)) elaborate_expression (gnat_hb, gnat_entity, "U", true, false, Needs_Debug_Info (gnat_entity)); break; } case E_Record_Subtype: case E_Private_Subtype: case E_Limited_Private_Subtype: case E_Record_Subtype_With_Private: if (Has_Discriminants (gnat_entity) && Is_Constrained (gnat_entity)) { Node_Id gnat_discriminant_expr; Entity_Id gnat_field; for (gnat_field = First_Discriminant (Implementation_Base_Type (gnat_entity)), gnat_discriminant_expr = First_Elmt (Discriminant_Constraint (gnat_entity)); Present (gnat_field); gnat_field = Next_Discriminant (gnat_field), gnat_discriminant_expr = Next_Elmt (gnat_discriminant_expr)) /* Ignore access discriminants. */ if (!Is_Access_Type (Etype (Node (gnat_discriminant_expr)))) elaborate_expression (Node (gnat_discriminant_expr), gnat_entity, get_entity_char (gnat_field), true, false, false); } break; } } /* Prepend to ATTR_LIST an entry for an attribute with provided TYPE, NAME, ARGS and ERROR_POINT. */ static void prepend_one_attribute (struct attrib **attr_list, enum attr_type attr_type, tree attr_name, tree attr_args, Node_Id attr_error_point) { struct attrib * attr = (struct attrib *) xmalloc (sizeof (struct attrib)); attr->type = attr_type; attr->name = attr_name; attr->args = attr_args; attr->error_point = attr_error_point; attr->next = *attr_list; *attr_list = attr; } /* Prepend to ATTR_LIST an entry for an attribute provided by GNAT_PRAGMA. */ static void prepend_one_attribute_pragma (struct attrib **attr_list, Node_Id gnat_pragma) { const Node_Id gnat_arg = Pragma_Argument_Associations (gnat_pragma); tree gnu_arg0 = NULL_TREE, gnu_arg1 = NULL_TREE; enum attr_type etype; /* Map the pragma at hand. Skip if this isn't one we know how to handle. */ switch (Get_Pragma_Id (Chars (Pragma_Identifier (gnat_pragma)))) { case Pragma_Machine_Attribute: etype = ATTR_MACHINE_ATTRIBUTE; break; case Pragma_Linker_Alias: etype = ATTR_LINK_ALIAS; break; case Pragma_Linker_Section: etype = ATTR_LINK_SECTION; break; case Pragma_Linker_Constructor: etype = ATTR_LINK_CONSTRUCTOR; break; case Pragma_Linker_Destructor: etype = ATTR_LINK_DESTRUCTOR; break; case Pragma_Weak_External: etype = ATTR_WEAK_EXTERNAL; break; case Pragma_Thread_Local_Storage: etype = ATTR_THREAD_LOCAL_STORAGE; break; default: return; } /* See what arguments we have and turn them into GCC trees for attribute handlers. These expect identifier for strings. We handle at most two arguments and static expressions only. */ if (Present (gnat_arg) && Present (First (gnat_arg))) { Node_Id gnat_arg0 = Next (First (gnat_arg)); Node_Id gnat_arg1 = Empty; if (Present (gnat_arg0) && Is_OK_Static_Expression (Expression (gnat_arg0))) { gnu_arg0 = gnat_to_gnu (Expression (gnat_arg0)); if (TREE_CODE (gnu_arg0) == STRING_CST) { gnu_arg0 = get_identifier (TREE_STRING_POINTER (gnu_arg0)); if (IDENTIFIER_LENGTH (gnu_arg0) == 0) return; } gnat_arg1 = Next (gnat_arg0); } if (Present (gnat_arg1) && Is_OK_Static_Expression (Expression (gnat_arg1))) { gnu_arg1 = gnat_to_gnu (Expression (gnat_arg1)); if (TREE_CODE (gnu_arg1) == STRING_CST) gnu_arg1 = get_identifier (TREE_STRING_POINTER (gnu_arg1)); } } /* Prepend to the list. Make a list of the argument we might have, as GCC expects it. */ prepend_one_attribute (attr_list, etype, gnu_arg0, gnu_arg1 ? build_tree_list (NULL_TREE, gnu_arg1) : NULL_TREE, Present (Next (First (gnat_arg))) ? Expression (Next (First (gnat_arg))) : gnat_pragma); } /* Prepend to ATTR_LIST the list of attributes for GNAT_ENTITY, if any. */ static void prepend_attributes (struct attrib **attr_list, Entity_Id gnat_entity) { Node_Id gnat_temp; /* Attributes are stored as Representation Item pragmas. */ for (gnat_temp = First_Rep_Item (gnat_entity); Present (gnat_temp); gnat_temp = Next_Rep_Item (gnat_temp)) if (Nkind (gnat_temp) == N_Pragma) prepend_one_attribute_pragma (attr_list, gnat_temp); } /* Given a GNAT tree GNAT_EXPR, for an expression which is a value within a type definition (either a bound or a discriminant value) for GNAT_ENTITY, return the GCC tree to use for that expression. S is the suffix to use if a variable needs to be created and DEFINITION is true if this is done for a definition of GNAT_ENTITY. If NEED_VALUE is true, we need a result; otherwise, we are just elaborating the expression for side-effects. If NEED_DEBUG is true, we need a variable for debugging purposes even if it isn't needed for code generation. */ static tree elaborate_expression (Node_Id gnat_expr, Entity_Id gnat_entity, const char *s, bool definition, bool need_value, bool need_debug) { tree gnu_expr; /* If we already elaborated this expression (e.g. it was involved in the definition of a private type), use the old value. */ if (present_gnu_tree (gnat_expr)) return get_gnu_tree (gnat_expr); /* If we don't need a value and this is static or a discriminant, we don't need to do anything. */ if (!need_value && (Is_OK_Static_Expression (gnat_expr) || (Nkind (gnat_expr) == N_Identifier && Ekind (Entity (gnat_expr)) == E_Discriminant))) return NULL_TREE; /* If it's a static expression, we don't need a variable for debugging. */ if (need_debug && Is_OK_Static_Expression (gnat_expr)) need_debug = false; /* Otherwise, convert this tree to its GCC equivalent and elaborate it. */ gnu_expr = elaborate_expression_1 (gnat_to_gnu (gnat_expr), gnat_entity, s, definition, need_debug); /* Save the expression in case we try to elaborate this entity again. Since it's not a DECL, don't check it. Don't save if it's a discriminant. */ if (!CONTAINS_PLACEHOLDER_P (gnu_expr)) save_gnu_tree (gnat_expr, gnu_expr, true); return need_value ? gnu_expr : error_mark_node; } /* Similar, but take a GNU expression and always return a result. */ static tree elaborate_expression_1 (tree gnu_expr, Entity_Id gnat_entity, const char *s, bool definition, bool need_debug) { const bool expr_public_p = Is_Public (gnat_entity); const bool expr_global_p = expr_public_p || global_bindings_p (); bool expr_variable_p, use_variable; /* If GNU_EXPR contains a placeholder, just return it. We rely on the fact that an expression cannot contain both a discriminant and a variable. */ if (CONTAINS_PLACEHOLDER_P (gnu_expr)) return gnu_expr; /* If GNU_EXPR is neither a constant nor based on a read-only variable, make a variable that is initialized to contain the expression when the package containing the definition is elaborated. If this entity is defined at top level, replace the expression by the variable; otherwise use a SAVE_EXPR if this is necessary. */ if (TREE_CONSTANT (gnu_expr)) expr_variable_p = false; else { /* Skip any conversions and simple constant arithmetics to see if the expression is based on a read-only variable. */ tree inner = remove_conversions (gnu_expr, true); inner = skip_simple_constant_arithmetic (inner); if (handled_component_p (inner)) inner = get_inner_constant_reference (inner); expr_variable_p = !(inner && TREE_CODE (inner) == VAR_DECL && (TREE_READONLY (inner) || DECL_READONLY_ONCE_ELAB (inner))); } /* We only need to use the variable if we are in a global context since GCC can do the right thing in the local case. However, when not optimizing, use it for bounds of loop iteration scheme to avoid code duplication. */ use_variable = expr_variable_p && (expr_global_p || (!optimize && definition && Is_Itype (gnat_entity) && Nkind (Associated_Node_For_Itype (gnat_entity)) == N_Loop_Parameter_Specification)); /* Now create it, possibly only for debugging purposes. */ if (use_variable || need_debug) { /* The following variable creation can happen when processing the body of subprograms that are defined out of the extended main unit and inlined. In this case, we are not at the global scope, and thus the new variable must not be tagged "external", as we used to do here as soon as DEFINITION was false. */ tree gnu_decl = create_var_decl_1 (create_concat_name (gnat_entity, s), NULL_TREE, TREE_TYPE (gnu_expr), gnu_expr, true, expr_public_p, !definition && expr_global_p, expr_global_p, !need_debug, NULL, gnat_entity); /* Whether or not gnat_entity comes from source, this variable is a compilation artifact. */ DECL_ARTIFICIAL (gnu_decl) = 1; /* Using this variable at debug time (if need_debug is true) requires a proper location. The back-end will compute a location for this variable only if the variable is used by the generated code. Returning the variable ensures the caller will use it in generated code. Note that there is no need for a location if the debug info contains an integer constant. FIXME: when the encoding-based debug scheme is dropped, move this condition to the top-level IF block: we will not need to create a variable anymore in such cases, then. */ if (use_variable || (need_debug && !TREE_CONSTANT (gnu_expr))) return gnu_decl; } return expr_variable_p ? gnat_save_expr (gnu_expr) : gnu_expr; } /* Similar, but take an alignment factor and make it explicit in the tree. */ static tree elaborate_expression_2 (tree gnu_expr, Entity_Id gnat_entity, const char *s, bool definition, bool need_debug, unsigned int align) { tree unit_align = size_int (align / BITS_PER_UNIT); return size_binop (MULT_EXPR, elaborate_expression_1 (size_binop (EXACT_DIV_EXPR, gnu_expr, unit_align), gnat_entity, s, definition, need_debug), unit_align); } /* Structure to hold internal data for elaborate_reference. */ struct er_data { Entity_Id entity; bool definition; unsigned int n; }; /* Wrapper function around elaborate_expression_1 for elaborate_reference. */ static tree elaborate_reference_1 (tree ref, void *data) { struct er_data *er = (struct er_data *)data; char suffix[16]; /* This is what elaborate_expression_1 does if NEED_DEBUG is false. */ if (TREE_CONSTANT (ref)) return ref; /* If this is a COMPONENT_REF of a fat pointer, elaborate the entire fat pointer. This may be more efficient, but will also allow us to more easily find the match for the PLACEHOLDER_EXPR. */ if (TREE_CODE (ref) == COMPONENT_REF && TYPE_IS_FAT_POINTER_P (TREE_TYPE (TREE_OPERAND (ref, 0)))) return build3 (COMPONENT_REF, TREE_TYPE (ref), elaborate_reference_1 (TREE_OPERAND (ref, 0), data), TREE_OPERAND (ref, 1), TREE_OPERAND (ref, 2)); sprintf (suffix, "EXP%d", ++er->n); return elaborate_expression_1 (ref, er->entity, suffix, er->definition, false); } /* Elaborate the reference REF to be used as renamed object for GNAT_ENTITY. DEFINITION is true if this is done for a definition of GNAT_ENTITY and INIT is set to the first arm of a COMPOUND_EXPR present in REF, if any. */ static tree elaborate_reference (tree ref, Entity_Id gnat_entity, bool definition, tree *init) { struct er_data er = { gnat_entity, definition, 0 }; return gnat_rewrite_reference (ref, elaborate_reference_1, &er, init); } /* Given a GNU tree and a GNAT list of choices, generate an expression to test the value passed against the list of choices. */ tree choices_to_gnu (tree operand, Node_Id choices) { Node_Id choice; Node_Id gnat_temp; tree result = boolean_false_node; tree this_test, low = 0, high = 0, single = 0; for (choice = First (choices); Present (choice); choice = Next (choice)) { switch (Nkind (choice)) { case N_Range: low = gnat_to_gnu (Low_Bound (choice)); high = gnat_to_gnu (High_Bound (choice)); this_test = build_binary_op (TRUTH_ANDIF_EXPR, boolean_type_node, build_binary_op (GE_EXPR, boolean_type_node, operand, low), build_binary_op (LE_EXPR, boolean_type_node, operand, high)); break; case N_Subtype_Indication: gnat_temp = Range_Expression (Constraint (choice)); low = gnat_to_gnu (Low_Bound (gnat_temp)); high = gnat_to_gnu (High_Bound (gnat_temp)); this_test = build_binary_op (TRUTH_ANDIF_EXPR, boolean_type_node, build_binary_op (GE_EXPR, boolean_type_node, operand, low), build_binary_op (LE_EXPR, boolean_type_node, operand, high)); break; case N_Identifier: case N_Expanded_Name: /* This represents either a subtype range, an enumeration literal, or a constant Ekind says which. If an enumeration literal or constant, fall through to the next case. */ if (Ekind (Entity (choice)) != E_Enumeration_Literal && Ekind (Entity (choice)) != E_Constant) { tree type = gnat_to_gnu_type (Entity (choice)); low = TYPE_MIN_VALUE (type); high = TYPE_MAX_VALUE (type); this_test = build_binary_op (TRUTH_ANDIF_EXPR, boolean_type_node, build_binary_op (GE_EXPR, boolean_type_node, operand, low), build_binary_op (LE_EXPR, boolean_type_node, operand, high)); break; } /* ... fall through ... */ case N_Character_Literal: case N_Integer_Literal: single = gnat_to_gnu (choice); this_test = build_binary_op (EQ_EXPR, boolean_type_node, operand, single); break; case N_Others_Choice: this_test = boolean_true_node; break; default: gcc_unreachable (); } result = build_binary_op (TRUTH_ORIF_EXPR, boolean_type_node, result, this_test); } return result; } /* Adjust PACKED setting as passed to gnat_to_gnu_field for a field of type FIELD_TYPE to be placed in RECORD_TYPE. Return the result. */ static int adjust_packed (tree field_type, tree record_type, int packed) { /* If the field contains an item of variable size, we cannot pack it because we cannot create temporaries of non-fixed size in case we need to take the address of the field. See addressable_p and the notes on the addressability issues for further details. */ if (type_has_variable_size (field_type)) return 0; /* If the alignment of the record is specified and the field type is over-aligned, request Storage_Unit alignment for the field. */ if (packed == -2) { if (TYPE_ALIGN (field_type) > TYPE_ALIGN (record_type)) return -1; else return 0; } return packed; } /* Return a GCC tree for a field corresponding to GNAT_FIELD to be placed in GNU_RECORD_TYPE. PACKED is 1 if the enclosing record is packed, -1 if the enclosing record has Component_Alignment of Storage_Unit, -2 if the enclosing record has a specified alignment. DEFINITION is true if this field is for a record being defined. DEBUG_INFO_P is true if we need to write debug information for types that we may create in the process. */ static tree gnat_to_gnu_field (Entity_Id gnat_field, tree gnu_record_type, int packed, bool definition, bool debug_info_p) { const Entity_Id gnat_field_type = Etype (gnat_field); const bool is_aliased = Is_Aliased (gnat_field); const bool is_atomic = (Is_Atomic_Or_VFA (gnat_field) || Is_Atomic_Or_VFA (gnat_field_type)); const bool is_independent = (Is_Independent (gnat_field) || Is_Independent (gnat_field_type)); const bool is_volatile = (Treat_As_Volatile (gnat_field) || Treat_As_Volatile (gnat_field_type)); const bool needs_strict_alignment = (is_aliased || is_independent || is_volatile || Strict_Alignment (gnat_field_type)); tree gnu_field_type = gnat_to_gnu_type (gnat_field_type); tree gnu_field_id = get_entity_name (gnat_field); tree gnu_field, gnu_size, gnu_pos; /* If this field requires strict alignment, we cannot pack it because it would very likely be under-aligned in the record. */ if (needs_strict_alignment) packed = 0; else packed = adjust_packed (gnu_field_type, gnu_record_type, packed); /* If a size is specified, use it. Otherwise, if the record type is packed, use the official RM size. See "Handling of Type'Size Values" in Einfo for further details. */ if (Known_Esize (gnat_field)) gnu_size = validate_size (Esize (gnat_field), gnu_field_type, gnat_field, FIELD_DECL, false, true); else if (packed == 1) gnu_size = validate_size (RM_Size (gnat_field_type), gnu_field_type, gnat_field, FIELD_DECL, false, true); else gnu_size = NULL_TREE; /* If we have a specified size that is smaller than that of the field's type, or a position is specified, and the field's type is a record that doesn't require strict alignment, see if we can get either an integral mode form of the type or a smaller form. If we can, show a size was specified for the field if there wasn't one already, so we know to make this a bitfield and avoid making things wider. Changing to an integral mode form is useful when the record is packed as we can then place the field at a non-byte-aligned position and so achieve tighter packing. This is in addition required if the field shares a byte with another field and the front-end lets the back-end handle the access to the field, because GCC cannot handle non-byte-aligned BLKmode fields. Changing to a smaller form is required if the specified size is smaller than that of the field's type and the type contains sub-fields that are padded, in order to avoid generating accesses to these sub-fields that are wider than the field. We avoid the transformation if it is not required or potentially useful, as it might entail an increase of the field's alignment and have ripple effects on the outer record type. A typical case is a field known to be byte-aligned and not to share a byte with another field. */ if (!needs_strict_alignment && RECORD_OR_UNION_TYPE_P (gnu_field_type) && !TYPE_FAT_POINTER_P (gnu_field_type) && tree_fits_uhwi_p (TYPE_SIZE (gnu_field_type)) && (packed == 1 || (gnu_size && (tree_int_cst_lt (gnu_size, TYPE_SIZE (gnu_field_type)) || (Present (Component_Clause (gnat_field)) && !(UI_To_Int (Component_Bit_Offset (gnat_field)) % BITS_PER_UNIT == 0 && value_factor_p (gnu_size, BITS_PER_UNIT))))))) { tree gnu_packable_type = make_packable_type (gnu_field_type, true); if (gnu_packable_type != gnu_field_type) { gnu_field_type = gnu_packable_type; if (!gnu_size) gnu_size = rm_size (gnu_field_type); } } if (Is_Atomic_Or_VFA (gnat_field)) check_ok_for_atomic_type (gnu_field_type, gnat_field, false); if (Present (Component_Clause (gnat_field))) { Node_Id gnat_clause = Component_Clause (gnat_field); Entity_Id gnat_parent = Parent_Subtype (Underlying_Type (Scope (gnat_field))); gnu_pos = UI_To_gnu (Component_Bit_Offset (gnat_field), bitsizetype); gnu_size = validate_size (Esize (gnat_field), gnu_field_type, gnat_field, FIELD_DECL, false, true); /* Ensure the position does not overlap with the parent subtype, if there is one. This test is omitted if the parent of the tagged type has a full rep clause since, in this case, component clauses are allowed to overlay the space allocated for the parent type and the front-end has checked that there are no overlapping components. */ if (Present (gnat_parent) && !Is_Fully_Repped_Tagged_Type (gnat_parent)) { tree gnu_parent = gnat_to_gnu_type (gnat_parent); if (TREE_CODE (TYPE_SIZE (gnu_parent)) == INTEGER_CST && tree_int_cst_lt (gnu_pos, TYPE_SIZE (gnu_parent))) post_error_ne_tree ("offset of& must be beyond parent{, minimum allowed is ^}", Position (gnat_clause), gnat_field, TYPE_SIZE_UNIT (gnu_parent)); } /* If this field needs strict alignment, make sure that the record is sufficiently aligned and that the position and size are consistent with the type. But don't do it if we are just annotating types and the field's type is tagged, since tagged types aren't fully laid out in this mode. Also, note that atomic implies volatile so the inner test sequences ordering is significant here. */ if (needs_strict_alignment && !(type_annotate_only && Is_Tagged_Type (gnat_field_type))) { const unsigned int type_align = TYPE_ALIGN (gnu_field_type); if (TYPE_ALIGN (gnu_record_type) < type_align) TYPE_ALIGN (gnu_record_type) = type_align; /* If the position is not a multiple of the alignment of the type, then error out and reset the position. */ if (!integer_zerop (size_binop (TRUNC_MOD_EXPR, gnu_pos, bitsize_int (type_align)))) { const char *s; if (is_atomic) s = "position of atomic field& must be multiple of ^ bits"; else if (is_aliased) s = "position of aliased field& must be multiple of ^ bits"; else if (is_independent) s = "position of independent field& must be multiple of ^ bits"; else if (is_volatile) s = "position of volatile field& must be multiple of ^ bits"; else if (Strict_Alignment (gnat_field_type)) s = "position of & with aliased or tagged part must be" " multiple of ^ bits"; else gcc_unreachable (); post_error_ne_num (s, First_Bit (gnat_clause), gnat_field, type_align); gnu_pos = NULL_TREE; } if (gnu_size) { tree gnu_type_size = TYPE_SIZE (gnu_field_type); const int cmp = tree_int_cst_compare (gnu_size, gnu_type_size); /* If the size is lower than that of the type, or greater for atomic and aliased, then error out and reset the size. */ if (cmp < 0 || (cmp > 0 && (is_atomic || is_aliased))) { const char *s; if (is_atomic) s = "size of atomic field& must be ^ bits"; else if (is_aliased) s = "size of aliased field& must be ^ bits"; else if (is_independent) s = "size of independent field& must be at least ^ bits"; else if (is_volatile) s = "size of volatile field& must be at least ^ bits"; else if (Strict_Alignment (gnat_field_type)) s = "size of & with aliased or tagged part must be" " at least ^ bits"; else gcc_unreachable (); post_error_ne_tree (s, Last_Bit (gnat_clause), gnat_field, gnu_type_size); gnu_size = NULL_TREE; } /* Likewise if the size is not a multiple of a byte, */ else if (!integer_zerop (size_binop (TRUNC_MOD_EXPR, gnu_size, bitsize_unit_node))) { const char *s; if (is_independent) s = "size of independent field& must be multiple of" " Storage_Unit"; else if (is_volatile) s = "size of volatile field& must be multiple of" " Storage_Unit"; else if (Strict_Alignment (gnat_field_type)) s = "size of & with aliased or tagged part must be" " multiple of Storage_Unit"; else gcc_unreachable (); post_error_ne (s, Last_Bit (gnat_clause), gnat_field); gnu_size = NULL_TREE; } } } } /* If the record has rep clauses and this is the tag field, make a rep clause for it as well. */ else if (Has_Specified_Layout (Scope (gnat_field)) && Chars (gnat_field) == Name_uTag) { gnu_pos = bitsize_zero_node; gnu_size = TYPE_SIZE (gnu_field_type); } else { gnu_pos = NULL_TREE; /* If we are packing the record and the field is BLKmode, round the size up to a byte boundary. */ if (packed && TYPE_MODE (gnu_field_type) == BLKmode && gnu_size) gnu_size = round_up (gnu_size, BITS_PER_UNIT); } /* We need to make the size the maximum for the type if it is self-referential and an unconstrained type. In that case, we can't pack the field since we can't make a copy to align it. */ if (TREE_CODE (gnu_field_type) == RECORD_TYPE && !gnu_size && CONTAINS_PLACEHOLDER_P (TYPE_SIZE (gnu_field_type)) && !Is_Constrained (Underlying_Type (gnat_field_type))) { gnu_size = max_size (TYPE_SIZE (gnu_field_type), true); packed = 0; } /* If a size is specified, adjust the field's type to it. */ if (gnu_size) { tree orig_field_type; /* If the field's type is justified modular, we would need to remove the wrapper to (better) meet the layout requirements. However we can do so only if the field is not aliased to preserve the unique layout and if the prescribed size is not greater than that of the packed array to preserve the justification. */ if (!needs_strict_alignment && TREE_CODE (gnu_field_type) == RECORD_TYPE && TYPE_JUSTIFIED_MODULAR_P (gnu_field_type) && tree_int_cst_compare (gnu_size, TYPE_ADA_SIZE (gnu_field_type)) <= 0) gnu_field_type = TREE_TYPE (TYPE_FIELDS (gnu_field_type)); /* Similarly if the field's type is a misaligned integral type, but there is no restriction on the size as there is no justification. */ if (!needs_strict_alignment && TYPE_IS_PADDING_P (gnu_field_type) && INTEGRAL_TYPE_P (TREE_TYPE (TYPE_FIELDS (gnu_field_type)))) gnu_field_type = TREE_TYPE (TYPE_FIELDS (gnu_field_type)); gnu_field_type = make_type_from_size (gnu_field_type, gnu_size, Has_Biased_Representation (gnat_field)); orig_field_type = gnu_field_type; gnu_field_type = maybe_pad_type (gnu_field_type, gnu_size, 0, gnat_field, false, false, definition, true); /* If a padding record was made, declare it now since it will never be declared otherwise. This is necessary to ensure that its subtrees are properly marked. */ if (gnu_field_type != orig_field_type && !DECL_P (TYPE_NAME (gnu_field_type))) create_type_decl (TYPE_NAME (gnu_field_type), gnu_field_type, true, debug_info_p, gnat_field); } /* Otherwise (or if there was an error), don't specify a position. */ else gnu_pos = NULL_TREE; gcc_assert (TREE_CODE (gnu_field_type) != RECORD_TYPE || !TYPE_CONTAINS_TEMPLATE_P (gnu_field_type)); /* Now create the decl for the field. */ gnu_field = create_field_decl (gnu_field_id, gnu_field_type, gnu_record_type, gnu_size, gnu_pos, packed, Is_Aliased (gnat_field)); Sloc_to_locus (Sloc (gnat_field), &DECL_SOURCE_LOCATION (gnu_field)); DECL_ALIASED_P (gnu_field) = Is_Aliased (gnat_field); TREE_THIS_VOLATILE (gnu_field) = TREE_SIDE_EFFECTS (gnu_field) = is_volatile; if (Ekind (gnat_field) == E_Discriminant) DECL_DISCRIMINANT_NUMBER (gnu_field) = UI_To_gnu (Discriminant_Number (gnat_field), sizetype); return gnu_field; } /* Return true if at least one member of COMPONENT_LIST needs strict alignment. */ static bool components_need_strict_alignment (Node_Id component_list) { Node_Id component_decl; for (component_decl = First_Non_Pragma (Component_Items (component_list)); Present (component_decl); component_decl = Next_Non_Pragma (component_decl)) { Entity_Id gnat_field = Defining_Entity (component_decl); if (Is_Aliased (gnat_field)) return true; if (Strict_Alignment (Etype (gnat_field))) return true; } return false; } /* Return true if TYPE is a type with variable size or a padding type with a field of variable size or a record that has a field with such a type. */ static bool type_has_variable_size (tree type) { tree field; if (!TREE_CONSTANT (TYPE_SIZE (type))) return true; if (TYPE_IS_PADDING_P (type) && !TREE_CONSTANT (DECL_SIZE (TYPE_FIELDS (type)))) return true; if (!RECORD_OR_UNION_TYPE_P (type)) return false; for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field)) if (type_has_variable_size (TREE_TYPE (field))) return true; return false; } /* Return true if FIELD is an artificial field. */ static bool field_is_artificial (tree field) { /* These fields are generated by the front-end proper. */ if (IDENTIFIER_POINTER (DECL_NAME (field)) [0] == '_') return true; /* These fields are generated by gigi. */ if (DECL_INTERNAL_P (field)) return true; return false; } /* Return true if FIELD is a non-artificial aliased field. */ static bool field_is_aliased (tree field) { if (field_is_artificial (field)) return false; return DECL_ALIASED_P (field); } /* Return true if FIELD is a non-artificial field with self-referential size. */ static bool field_has_self_size (tree field) { if (field_is_artificial (field)) return false; if (DECL_SIZE (field) && TREE_CODE (DECL_SIZE (field)) == INTEGER_CST) return false; return CONTAINS_PLACEHOLDER_P (TYPE_SIZE (TREE_TYPE (field))); } /* Return true if FIELD is a non-artificial field with variable size. */ static bool field_has_variable_size (tree field) { if (field_is_artificial (field)) return false; if (DECL_SIZE (field) && TREE_CODE (DECL_SIZE (field)) == INTEGER_CST) return false; return TREE_CODE (TYPE_SIZE (TREE_TYPE (field))) != INTEGER_CST; } /* qsort comparer for the bit positions of two record components. */ static int compare_field_bitpos (const PTR rt1, const PTR rt2) { const_tree const field1 = * (const_tree const *) rt1; const_tree const field2 = * (const_tree const *) rt2; const int ret = tree_int_cst_compare (bit_position (field1), bit_position (field2)); return ret ? ret : (int) (DECL_UID (field1) - DECL_UID (field2)); } /* Structure holding information for a given variant. */ typedef struct vinfo { /* The record type of the variant. */ tree type; /* The name of the variant. */ tree name; /* The qualifier of the variant. */ tree qual; /* Whether the variant has a rep clause. */ bool has_rep; /* Whether the variant is packed. */ bool packed; } vinfo_t; /* Translate and chain the GNAT_COMPONENT_LIST to the GNU_FIELD_LIST, set the result as the field list of GNU_RECORD_TYPE and finish it up. Return true if GNU_RECORD_TYPE has a rep clause which affects the layout (see below). When called from gnat_to_gnu_entity during the processing of a record type definition, the GCC node for the parent, if any, will be the single field of GNU_RECORD_TYPE and the GCC nodes for the discriminants will be on the GNU_FIELD_LIST. The other calls to this function are recursive calls for the component list of a variant and, in this case, GNU_FIELD_LIST is empty. PACKED is 1 if this is for a packed record, -1 if this is for a record with Component_Alignment of Storage_Unit, -2 if this is for a record with a specified alignment. DEFINITION is true if we are defining this record type. CANCEL_ALIGNMENT is true if the alignment should be zeroed before laying out the record. This means the alignment only serves to force fields to be bitfields, but not to require the record to be that aligned. This is used for variants. ALL_REP is true if a rep clause is present for all the fields. UNCHECKED_UNION is true if we are building this type for a record with a Pragma Unchecked_Union. ARTIFICIAL is true if this is a type that was generated by the compiler. DEBUG_INFO is true if we need to write debug information about the type. MAYBE_UNUSED is true if this type may be unused in the end; this doesn't mean that its contents may be unused as well, only the container itself. REORDER is true if we are permitted to reorder components of this type. FIRST_FREE_POS, if nonzero, is the first (lowest) free field position in the outer record type down to this variant level. It is nonzero only if all the fields down to this level have a rep clause and ALL_REP is false. P_GNU_REP_LIST, if nonzero, is a pointer to a list to which each field with a rep clause is to be added; in this case, that is all that should be done with such fields and the return value will be false. */ static bool components_to_record (tree gnu_record_type, Node_Id gnat_component_list, tree gnu_field_list, int packed, bool definition, bool cancel_alignment, bool all_rep, bool unchecked_union, bool artificial, bool debug_info, bool maybe_unused, bool reorder, tree first_free_pos, tree *p_gnu_rep_list) { bool all_rep_and_size = all_rep && TYPE_SIZE (gnu_record_type); bool variants_have_rep = all_rep; bool layout_with_rep = false; bool has_self_field = false; bool has_aliased_after_self_field = false; Node_Id component_decl, variant_part; tree gnu_field, gnu_next, gnu_last; tree gnu_variant_part = NULL_TREE; tree gnu_rep_list = NULL_TREE; tree gnu_var_list = NULL_TREE; tree gnu_self_list = NULL_TREE; tree gnu_zero_list = NULL_TREE; /* For each component referenced in a component declaration create a GCC field and add it to the list, skipping pragmas in the GNAT list. */ gnu_last = tree_last (gnu_field_list); if (Present (Component_Items (gnat_component_list))) for (component_decl = First_Non_Pragma (Component_Items (gnat_component_list)); Present (component_decl); component_decl = Next_Non_Pragma (component_decl)) { Entity_Id gnat_field = Defining_Entity (component_decl); Name_Id gnat_name = Chars (gnat_field); /* If present, the _Parent field must have been created as the single field of the record type. Put it before any other fields. */ if (gnat_name == Name_uParent) { gnu_field = TYPE_FIELDS (gnu_record_type); gnu_field_list = chainon (gnu_field_list, gnu_field); } else { gnu_field = gnat_to_gnu_field (gnat_field, gnu_record_type, packed, definition, debug_info); /* If this is the _Tag field, put it before any other fields. */ if (gnat_name == Name_uTag) gnu_field_list = chainon (gnu_field_list, gnu_field); /* If this is the _Controller field, put it before the other fields except for the _Tag or _Parent field. */ else if (gnat_name == Name_uController && gnu_last) { DECL_CHAIN (gnu_field) = DECL_CHAIN (gnu_last); DECL_CHAIN (gnu_last) = gnu_field; } /* If this is a regular field, put it after the other fields. */ else { DECL_CHAIN (gnu_field) = gnu_field_list; gnu_field_list = gnu_field; if (!gnu_last) gnu_last = gnu_field; /* And record information for the final layout. */ if (field_has_self_size (gnu_field)) has_self_field = true; else if (has_self_field && field_is_aliased (gnu_field)) has_aliased_after_self_field = true; } } save_gnu_tree (gnat_field, gnu_field, false); } /* At the end of the component list there may be a variant part. */ variant_part = Variant_Part (gnat_component_list); /* We create a QUAL_UNION_TYPE for the variant part since the variants are mutually exclusive and should go in the same memory. To do this we need to treat each variant as a record whose elements are created from the component list for the variant. So here we create the records from the lists for the variants and put them all into the QUAL_UNION_TYPE. If this is an Unchecked_Union, we make a UNION_TYPE instead or use GNU_RECORD_TYPE if there are no fields so far. */ if (Present (variant_part)) { Node_Id gnat_discr = Name (variant_part), variant; tree gnu_discr = gnat_to_gnu (gnat_discr); tree gnu_name = TYPE_IDENTIFIER (gnu_record_type); tree gnu_var_name = concat_name (get_identifier (Get_Name_String (Chars (gnat_discr))), "XVN"); tree gnu_union_type, gnu_union_name; tree this_first_free_pos, gnu_variant_list = NULL_TREE; bool union_field_needs_strict_alignment = false; auto_vec variant_types; vinfo_t *gnu_variant; unsigned int variants_align = 0; unsigned int i; gnu_union_name = concat_name (gnu_name, IDENTIFIER_POINTER (gnu_var_name)); /* Reuse the enclosing union if this is an Unchecked_Union whose fields are all in the variant part, to match the layout of C unions. There is an associated check below. */ if (TREE_CODE (gnu_record_type) == UNION_TYPE) gnu_union_type = gnu_record_type; else { gnu_union_type = make_node (unchecked_union ? UNION_TYPE : QUAL_UNION_TYPE); TYPE_NAME (gnu_union_type) = gnu_union_name; TYPE_ALIGN (gnu_union_type) = 0; TYPE_PACKED (gnu_union_type) = TYPE_PACKED (gnu_record_type); } /* If all the fields down to this level have a rep clause, find out whether all the fields at this level also have one. If so, then compute the new first free position to be passed downward. */ this_first_free_pos = first_free_pos; if (this_first_free_pos) { for (gnu_field = gnu_field_list; gnu_field; gnu_field = DECL_CHAIN (gnu_field)) if (DECL_FIELD_OFFSET (gnu_field)) { tree pos = bit_position (gnu_field); if (!tree_int_cst_lt (pos, this_first_free_pos)) this_first_free_pos = size_binop (PLUS_EXPR, pos, DECL_SIZE (gnu_field)); } else { this_first_free_pos = NULL_TREE; break; } } /* We build the variants in two passes. The bulk of the work is done in the first pass, that is to say translating the GNAT nodes, building the container types and computing the associated properties. However we cannot finish up the container types during this pass because we don't know where the variant part will be placed until the end. */ for (variant = First_Non_Pragma (Variants (variant_part)); Present (variant); variant = Next_Non_Pragma (variant)) { tree gnu_variant_type = make_node (RECORD_TYPE); tree gnu_inner_name, gnu_qual; bool has_rep; int field_packed; vinfo_t vinfo; Get_Variant_Encoding (variant); gnu_inner_name = get_identifier_with_length (Name_Buffer, Name_Len); TYPE_NAME (gnu_variant_type) = concat_name (gnu_union_name, IDENTIFIER_POINTER (gnu_inner_name)); /* Set the alignment of the inner type in case we need to make inner objects into bitfields, but then clear it out so the record actually gets only the alignment required. */ TYPE_ALIGN (gnu_variant_type) = TYPE_ALIGN (gnu_record_type); TYPE_PACKED (gnu_variant_type) = TYPE_PACKED (gnu_record_type); /* Similarly, if the outer record has a size specified and all the fields have a rep clause, we can propagate the size. */ if (all_rep_and_size) { TYPE_SIZE (gnu_variant_type) = TYPE_SIZE (gnu_record_type); TYPE_SIZE_UNIT (gnu_variant_type) = TYPE_SIZE_UNIT (gnu_record_type); } /* Add the fields into the record type for the variant. Note that we aren't sure to really use it at this point, see below. */ has_rep = components_to_record (gnu_variant_type, Component_List (variant), NULL_TREE, packed, definition, !all_rep_and_size, all_rep, unchecked_union, true, debug_info, true, reorder, this_first_free_pos, all_rep || this_first_free_pos ? NULL : &gnu_rep_list); /* Translate the qualifier and annotate the GNAT node. */ gnu_qual = choices_to_gnu (gnu_discr, Discrete_Choices (variant)); Set_Present_Expr (variant, annotate_value (gnu_qual)); /* Deal with packedness like in gnat_to_gnu_field. */ if (components_need_strict_alignment (Component_List (variant))) { field_packed = 0; union_field_needs_strict_alignment = true; } else field_packed = adjust_packed (gnu_variant_type, gnu_record_type, packed); /* Push this variant onto the stack for the second pass. */ vinfo.type = gnu_variant_type; vinfo.name = gnu_inner_name; vinfo.qual = gnu_qual; vinfo.has_rep = has_rep; vinfo.packed = field_packed; variant_types.safe_push (vinfo); /* Compute the global properties that will determine the placement of the variant part. */ variants_have_rep |= has_rep; if (!field_packed && TYPE_ALIGN (gnu_variant_type) > variants_align) variants_align = TYPE_ALIGN (gnu_variant_type); } /* Round up the first free position to the alignment of the variant part for the variants without rep clause. This will guarantee a consistent layout independently of the placement of the variant part. */ if (variants_have_rep && variants_align > 0 && this_first_free_pos) this_first_free_pos = round_up (this_first_free_pos, variants_align); /* In the second pass, the container types are adjusted if necessary and finished up, then the corresponding fields of the variant part are built with their qualifier, unless this is an unchecked union. */ FOR_EACH_VEC_ELT (variant_types, i, gnu_variant) { tree gnu_variant_type = gnu_variant->type; tree gnu_field_list = TYPE_FIELDS (gnu_variant_type); /* If this is an Unchecked_Union whose fields are all in the variant part and we have a single field with no representation clause or placed at offset zero, use the field directly to match the layout of C unions. */ if (TREE_CODE (gnu_record_type) == UNION_TYPE && gnu_field_list && !DECL_CHAIN (gnu_field_list) && (!DECL_FIELD_OFFSET (gnu_field_list) || integer_zerop (bit_position (gnu_field_list)))) { gnu_field = gnu_field_list; DECL_CONTEXT (gnu_field) = gnu_record_type; } else { /* Finalize the variant type now. We used to throw away empty record types but we no longer do that because we need them to generate complete debug info for the variant; otherwise, the union type definition will be lacking the fields associated with these empty variants. */ if (gnu_field_list && variants_have_rep && !gnu_variant->has_rep) { /* The variant part will be at offset 0 so we need to ensure that the fields are laid out starting from the first free position at this level. */ tree gnu_rep_type = make_node (RECORD_TYPE); tree gnu_rep_part; finish_record_type (gnu_rep_type, NULL_TREE, 0, debug_info); gnu_rep_part = create_rep_part (gnu_rep_type, gnu_variant_type, this_first_free_pos); DECL_CHAIN (gnu_rep_part) = gnu_field_list; gnu_field_list = gnu_rep_part; finish_record_type (gnu_variant_type, gnu_field_list, 0, false); } if (debug_info) rest_of_record_type_compilation (gnu_variant_type); create_type_decl (TYPE_NAME (gnu_variant_type), gnu_variant_type, true, debug_info, gnat_component_list); gnu_field = create_field_decl (gnu_variant->name, gnu_variant_type, gnu_union_type, all_rep_and_size ? TYPE_SIZE (gnu_variant_type) : 0, variants_have_rep ? bitsize_zero_node : 0, gnu_variant->packed, 0); DECL_INTERNAL_P (gnu_field) = 1; if (!unchecked_union) DECL_QUALIFIER (gnu_field) = gnu_variant->qual; } DECL_CHAIN (gnu_field) = gnu_variant_list; gnu_variant_list = gnu_field; } /* Only make the QUAL_UNION_TYPE if there are non-empty variants. */ if (gnu_variant_list) { int union_field_packed; if (all_rep_and_size) { TYPE_SIZE (gnu_union_type) = TYPE_SIZE (gnu_record_type); TYPE_SIZE_UNIT (gnu_union_type) = TYPE_SIZE_UNIT (gnu_record_type); } finish_record_type (gnu_union_type, nreverse (gnu_variant_list), all_rep_and_size ? 1 : 0, debug_info); /* If GNU_UNION_TYPE is our record type, it means we must have an Unchecked_Union with no fields. Verify that and, if so, just return. */ if (gnu_union_type == gnu_record_type) { gcc_assert (unchecked_union && !gnu_field_list && !gnu_rep_list); return variants_have_rep; } create_type_decl (TYPE_NAME (gnu_union_type), gnu_union_type, true, debug_info, gnat_component_list); /* Deal with packedness like in gnat_to_gnu_field. */ if (union_field_needs_strict_alignment) union_field_packed = 0; else union_field_packed = adjust_packed (gnu_union_type, gnu_record_type, packed); gnu_variant_part = create_field_decl (gnu_var_name, gnu_union_type, gnu_record_type, all_rep_and_size ? TYPE_SIZE (gnu_union_type) : 0, variants_have_rep ? bitsize_zero_node : 0, union_field_packed, 0); DECL_INTERNAL_P (gnu_variant_part) = 1; } } /* Scan GNU_FIELD_LIST and see if any fields have rep clauses and, if we are permitted to reorder components, self-referential sizes or variable sizes. If they do, pull them out and put them onto the appropriate list. We have to do this in a separate pass since we want to handle the discriminants but can't play with them until we've used them in debugging data above. Similarly, pull out the fields with zero size and no rep clause, as they would otherwise modify the layout and thus very likely run afoul of the Ada semantics, which are different from those of C here. ??? If we reorder them, debugging information will be wrong but there is nothing that can be done about this at the moment. */ gnu_last = NULL_TREE; #define MOVE_FROM_FIELD_LIST_TO(LIST) \ do { \ if (gnu_last) \ DECL_CHAIN (gnu_last) = gnu_next; \ else \ gnu_field_list = gnu_next; \ \ DECL_CHAIN (gnu_field) = (LIST); \ (LIST) = gnu_field; \ } while (0) for (gnu_field = gnu_field_list; gnu_field; gnu_field = gnu_next) { gnu_next = DECL_CHAIN (gnu_field); if (DECL_FIELD_OFFSET (gnu_field)) { MOVE_FROM_FIELD_LIST_TO (gnu_rep_list); continue; } if ((reorder || has_aliased_after_self_field) && field_has_self_size (gnu_field)) { MOVE_FROM_FIELD_LIST_TO (gnu_self_list); continue; } if (reorder && field_has_variable_size (gnu_field)) { MOVE_FROM_FIELD_LIST_TO (gnu_var_list); continue; } if (DECL_SIZE (gnu_field) && integer_zerop (DECL_SIZE (gnu_field))) { DECL_FIELD_OFFSET (gnu_field) = size_zero_node; SET_DECL_OFFSET_ALIGN (gnu_field, BIGGEST_ALIGNMENT); DECL_FIELD_BIT_OFFSET (gnu_field) = bitsize_zero_node; if (field_is_aliased (gnu_field)) TYPE_ALIGN (gnu_record_type) = MAX (TYPE_ALIGN (gnu_record_type), TYPE_ALIGN (TREE_TYPE (gnu_field))); MOVE_FROM_FIELD_LIST_TO (gnu_zero_list); continue; } gnu_last = gnu_field; } #undef MOVE_FROM_FIELD_LIST_TO gnu_field_list = nreverse (gnu_field_list); /* If permitted, we reorder the fields as follows: 1) all fixed length fields, 2) all fields whose length doesn't depend on discriminants, 3) all fields whose length depends on discriminants, 4) the variant part, within the record and within each variant recursively. */ if (reorder) gnu_field_list = chainon (gnu_field_list, chainon (gnu_var_list, gnu_self_list)); /* Otherwise, if there is an aliased field placed after a field whose length depends on discriminants, we put all the fields of the latter sort, last. We need to do this in case an object of this record type is mutable. */ else if (has_aliased_after_self_field) gnu_field_list = chainon (gnu_field_list, gnu_self_list); /* If P_REP_LIST is nonzero, this means that we are asked to move the fields in our REP list to the previous level because this level needs them in order to do a correct layout, i.e. avoid having overlapping fields. */ if (p_gnu_rep_list && gnu_rep_list) *p_gnu_rep_list = chainon (*p_gnu_rep_list, gnu_rep_list); /* Otherwise, sort the fields by bit position and put them into their own record, before the others, if we also have fields without rep clause. */ else if (gnu_rep_list) { tree gnu_rep_type, gnu_rep_part; int i, len = list_length (gnu_rep_list); tree *gnu_arr = XALLOCAVEC (tree, len); /* If all the fields have a rep clause, we can do a flat layout. */ layout_with_rep = !gnu_field_list && (!gnu_variant_part || variants_have_rep); gnu_rep_type = layout_with_rep ? gnu_record_type : make_node (RECORD_TYPE); for (gnu_field = gnu_rep_list, i = 0; gnu_field; gnu_field = DECL_CHAIN (gnu_field), i++) gnu_arr[i] = gnu_field; qsort (gnu_arr, len, sizeof (tree), compare_field_bitpos); /* Put the fields in the list in order of increasing position, which means we start from the end. */ gnu_rep_list = NULL_TREE; for (i = len - 1; i >= 0; i--) { DECL_CHAIN (gnu_arr[i]) = gnu_rep_list; gnu_rep_list = gnu_arr[i]; DECL_CONTEXT (gnu_arr[i]) = gnu_rep_type; } if (layout_with_rep) gnu_field_list = gnu_rep_list; else { finish_record_type (gnu_rep_type, gnu_rep_list, 1, debug_info); /* If FIRST_FREE_POS is nonzero, we need to ensure that the fields without rep clause are laid out starting from this position. Therefore, we force it as a minimal size on the REP part. */ gnu_rep_part = create_rep_part (gnu_rep_type, gnu_record_type, first_free_pos); /* Chain the REP part at the beginning of the field list. */ DECL_CHAIN (gnu_rep_part) = gnu_field_list; gnu_field_list = gnu_rep_part; } } /* Chain the variant part at the end of the field list. */ if (gnu_variant_part) gnu_field_list = chainon (gnu_field_list, gnu_variant_part); if (cancel_alignment) TYPE_ALIGN (gnu_record_type) = 0; TYPE_ARTIFICIAL (gnu_record_type) = artificial; finish_record_type (gnu_record_type, gnu_field_list, layout_with_rep ? 1 : 0, debug_info && !maybe_unused); /* Chain the fields with zero size at the beginning of the field list. */ if (gnu_zero_list) TYPE_FIELDS (gnu_record_type) = chainon (gnu_zero_list, TYPE_FIELDS (gnu_record_type)); return (gnu_rep_list && !p_gnu_rep_list) || variants_have_rep; } /* Given GNU_SIZE, a GCC tree representing a size, return a Uint to be placed into an Esize, Component_Bit_Offset, or Component_Size value in the GNAT tree. */ static Uint annotate_value (tree gnu_size) { TCode tcode; Node_Ref_Or_Val ops[3], ret, pre_op1 = No_Uint; struct tree_int_map in; int i; /* See if we've already saved the value for this node. */ if (EXPR_P (gnu_size)) { struct tree_int_map *e; in.base.from = gnu_size; e = annotate_value_cache->find (&in); if (e) return (Node_Ref_Or_Val) e->to; } else in.base.from = NULL_TREE; /* If we do not return inside this switch, TCODE will be set to the code to use for a Create_Node operand and LEN (set above) will be the number of recursive calls for us to make. */ switch (TREE_CODE (gnu_size)) { case INTEGER_CST: return TREE_OVERFLOW (gnu_size) ? No_Uint : UI_From_gnu (gnu_size); case COMPONENT_REF: /* The only case we handle here is a simple discriminant reference. */ if (DECL_DISCRIMINANT_NUMBER (TREE_OPERAND (gnu_size, 1))) { tree n = DECL_DISCRIMINANT_NUMBER (TREE_OPERAND (gnu_size, 1)); /* Climb up the chain of successive extensions, if any. */ while (TREE_CODE (TREE_OPERAND (gnu_size, 0)) == COMPONENT_REF && DECL_NAME (TREE_OPERAND (TREE_OPERAND (gnu_size, 0), 1)) == parent_name_id) gnu_size = TREE_OPERAND (gnu_size, 0); if (TREE_CODE (TREE_OPERAND (gnu_size, 0)) == PLACEHOLDER_EXPR) return Create_Node (Discrim_Val, annotate_value (n), No_Uint, No_Uint); } return No_Uint; CASE_CONVERT: case NON_LVALUE_EXPR: return annotate_value (TREE_OPERAND (gnu_size, 0)); /* Now just list the operations we handle. */ case COND_EXPR: tcode = Cond_Expr; break; case PLUS_EXPR: tcode = Plus_Expr; break; case MINUS_EXPR: tcode = Minus_Expr; break; case MULT_EXPR: tcode = Mult_Expr; break; case TRUNC_DIV_EXPR: tcode = Trunc_Div_Expr; break; case CEIL_DIV_EXPR: tcode = Ceil_Div_Expr; break; case FLOOR_DIV_EXPR: tcode = Floor_Div_Expr; break; case TRUNC_MOD_EXPR: tcode = Trunc_Mod_Expr; break; case CEIL_MOD_EXPR: tcode = Ceil_Mod_Expr; break; case FLOOR_MOD_EXPR: tcode = Floor_Mod_Expr; break; case EXACT_DIV_EXPR: tcode = Exact_Div_Expr; break; case NEGATE_EXPR: tcode = Negate_Expr; break; case MIN_EXPR: tcode = Min_Expr; break; case MAX_EXPR: tcode = Max_Expr; break; case ABS_EXPR: tcode = Abs_Expr; break; case TRUTH_ANDIF_EXPR: tcode = Truth_Andif_Expr; break; case TRUTH_ORIF_EXPR: tcode = Truth_Orif_Expr; break; case TRUTH_AND_EXPR: tcode = Truth_And_Expr; break; case TRUTH_OR_EXPR: tcode = Truth_Or_Expr; break; case TRUTH_XOR_EXPR: tcode = Truth_Xor_Expr; break; case TRUTH_NOT_EXPR: tcode = Truth_Not_Expr; break; case LT_EXPR: tcode = Lt_Expr; break; case LE_EXPR: tcode = Le_Expr; break; case GT_EXPR: tcode = Gt_Expr; break; case GE_EXPR: tcode = Ge_Expr; break; case EQ_EXPR: tcode = Eq_Expr; break; case NE_EXPR: tcode = Ne_Expr; break; case BIT_AND_EXPR: tcode = Bit_And_Expr; /* For negative values in sizetype, build NEGATE_EXPR of the opposite. Such values appear in expressions with aligning patterns. Note that, since sizetype is unsigned, we have to jump through some hoops. */ if (TREE_CODE (TREE_OPERAND (gnu_size, 1)) == INTEGER_CST) { tree op1 = TREE_OPERAND (gnu_size, 1); wide_int signed_op1 = wi::sext (op1, TYPE_PRECISION (sizetype)); if (wi::neg_p (signed_op1)) { op1 = wide_int_to_tree (sizetype, wi::neg (signed_op1)); pre_op1 = annotate_value (build1 (NEGATE_EXPR, sizetype, op1)); } } break; case CALL_EXPR: /* In regular mode, inline back only if symbolic annotation is requested in order to avoid memory explosion on big discriminated record types. But not in ASIS mode, as symbolic annotation is required for DDA. */ if (List_Representation_Info == 3 || type_annotate_only) { tree t = maybe_inline_call_in_expr (gnu_size); if (t) return annotate_value (t); } else return Uint_Minus_1; /* Fall through... */ default: return No_Uint; } /* Now get each of the operands that's relevant for this code. If any cannot be expressed as a repinfo node, say we can't. */ for (i = 0; i < 3; i++) ops[i] = No_Uint; for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (gnu_size)); i++) { if (i == 1 && pre_op1 != No_Uint) ops[i] = pre_op1; else ops[i] = annotate_value (TREE_OPERAND (gnu_size, i)); if (ops[i] == No_Uint) return No_Uint; } ret = Create_Node (tcode, ops[0], ops[1], ops[2]); /* Save the result in the cache. */ if (in.base.from) { struct tree_int_map **h; /* We can't assume the hash table data hasn't moved since the initial look up, so we have to search again. Allocating and inserting an entry at that point would be an alternative, but then we'd better discard the entry if we decided not to cache it. */ h = annotate_value_cache->find_slot (&in, INSERT); gcc_assert (!*h); *h = ggc_alloc (); (*h)->base.from = gnu_size; (*h)->to = ret; } return ret; } /* Given GNAT_ENTITY, an object (constant, variable, parameter, exception) and GNU_TYPE, its corresponding GCC type, set Esize and Alignment to the size and alignment used by Gigi. Prefer SIZE over TYPE_SIZE if non-null. BY_REF is true if the object is used by reference. */ void annotate_object (Entity_Id gnat_entity, tree gnu_type, tree size, bool by_ref) { if (by_ref) { if (TYPE_IS_FAT_POINTER_P (gnu_type)) gnu_type = TYPE_UNCONSTRAINED_ARRAY (gnu_type); else gnu_type = TREE_TYPE (gnu_type); } if (Unknown_Esize (gnat_entity)) { if (TREE_CODE (gnu_type) == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (gnu_type)) size = TYPE_SIZE (TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (gnu_type)))); else if (!size) size = TYPE_SIZE (gnu_type); if (size) Set_Esize (gnat_entity, annotate_value (size)); } if (Unknown_Alignment (gnat_entity)) Set_Alignment (gnat_entity, UI_From_Int (TYPE_ALIGN (gnu_type) / BITS_PER_UNIT)); } /* Return first element of field list whose TREE_PURPOSE is the same as ELEM. Return NULL_TREE if there is no such element in the list. */ static tree purpose_member_field (const_tree elem, tree list) { while (list) { tree field = TREE_PURPOSE (list); if (SAME_FIELD_P (field, elem)) return list; list = TREE_CHAIN (list); } return NULL_TREE; } /* Given GNAT_ENTITY, a record type, and GNU_TYPE, its corresponding GCC type, set Component_Bit_Offset and Esize of the components to the position and size used by Gigi. */ static void annotate_rep (Entity_Id gnat_entity, tree gnu_type) { Entity_Id gnat_field; tree gnu_list; /* We operate by first making a list of all fields and their position (we can get the size easily) and then update all the sizes in the tree. */ gnu_list = build_position_list (gnu_type, false, size_zero_node, bitsize_zero_node, BIGGEST_ALIGNMENT, NULL_TREE); for (gnat_field = First_Entity (gnat_entity); Present (gnat_field); gnat_field = Next_Entity (gnat_field)) if (Ekind (gnat_field) == E_Component || (Ekind (gnat_field) == E_Discriminant && !Is_Unchecked_Union (Scope (gnat_field)))) { tree t = purpose_member_field (gnat_to_gnu_field_decl (gnat_field), gnu_list); if (t) { tree parent_offset; /* If we are just annotating types and the type is tagged, the tag and the parent components are not generated by the front-end so we need to add the appropriate offset to each component without representation clause. */ if (type_annotate_only && Is_Tagged_Type (gnat_entity) && No (Component_Clause (gnat_field))) { /* For a component appearing in the current extension, the offset is the size of the parent. */ if (Is_Derived_Type (gnat_entity) && Original_Record_Component (gnat_field) == gnat_field) parent_offset = UI_To_gnu (Esize (Etype (Base_Type (gnat_entity))), bitsizetype); else parent_offset = bitsize_int (POINTER_SIZE); if (TYPE_FIELDS (gnu_type)) parent_offset = round_up (parent_offset, DECL_ALIGN (TYPE_FIELDS (gnu_type))); } else parent_offset = bitsize_zero_node; Set_Component_Bit_Offset (gnat_field, annotate_value (size_binop (PLUS_EXPR, bit_from_pos (TREE_VEC_ELT (TREE_VALUE (t), 0), TREE_VEC_ELT (TREE_VALUE (t), 2)), parent_offset))); Set_Esize (gnat_field, annotate_value (DECL_SIZE (TREE_PURPOSE (t)))); } else if (Is_Tagged_Type (gnat_entity) && Is_Derived_Type (gnat_entity)) { /* If there is no entry, this is an inherited component whose position is the same as in the parent type. */ Set_Component_Bit_Offset (gnat_field, Component_Bit_Offset (Original_Record_Component (gnat_field))); Set_Esize (gnat_field, Esize (Original_Record_Component (gnat_field))); } } } /* Scan all fields in GNU_TYPE and return a TREE_LIST where TREE_PURPOSE is the FIELD_DECL and TREE_VALUE a TREE_VEC containing the byte position, the value to be placed into DECL_OFFSET_ALIGN and the bit position. The list of fields is flattened, except for variant parts if DO_NOT_FLATTEN_VARIANT is set to true. GNU_POS is to be added to the position, GNU_BITPOS to the bit position, OFFSET_ALIGN is the present offset alignment. GNU_LIST is a pre-existing list to be chained to the newly created entries. */ static tree build_position_list (tree gnu_type, bool do_not_flatten_variant, tree gnu_pos, tree gnu_bitpos, unsigned int offset_align, tree gnu_list) { tree gnu_field; for (gnu_field = TYPE_FIELDS (gnu_type); gnu_field; gnu_field = DECL_CHAIN (gnu_field)) { tree gnu_our_bitpos = size_binop (PLUS_EXPR, gnu_bitpos, DECL_FIELD_BIT_OFFSET (gnu_field)); tree gnu_our_offset = size_binop (PLUS_EXPR, gnu_pos, DECL_FIELD_OFFSET (gnu_field)); unsigned int our_offset_align = MIN (offset_align, DECL_OFFSET_ALIGN (gnu_field)); tree v = make_tree_vec (3); TREE_VEC_ELT (v, 0) = gnu_our_offset; TREE_VEC_ELT (v, 1) = size_int (our_offset_align); TREE_VEC_ELT (v, 2) = gnu_our_bitpos; gnu_list = tree_cons (gnu_field, v, gnu_list); /* Recurse on internal fields, flattening the nested fields except for those in the variant part, if requested. */ if (DECL_INTERNAL_P (gnu_field)) { tree gnu_field_type = TREE_TYPE (gnu_field); if (do_not_flatten_variant && TREE_CODE (gnu_field_type) == QUAL_UNION_TYPE) gnu_list = build_position_list (gnu_field_type, do_not_flatten_variant, size_zero_node, bitsize_zero_node, BIGGEST_ALIGNMENT, gnu_list); else gnu_list = build_position_list (gnu_field_type, do_not_flatten_variant, gnu_our_offset, gnu_our_bitpos, our_offset_align, gnu_list); } } return gnu_list; } /* Return a list describing the substitutions needed to reflect the discriminant substitutions from GNAT_TYPE to GNAT_SUBTYPE. They can be in any order. The values in an element of the list are in the form of operands to SUBSTITUTE_IN_EXPR. DEFINITION is true if this is for a definition of GNAT_SUBTYPE. */ static vec build_subst_list (Entity_Id gnat_subtype, Entity_Id gnat_type, bool definition) { vec gnu_list = vNULL; Entity_Id gnat_discrim; Node_Id gnat_constr; for (gnat_discrim = First_Stored_Discriminant (gnat_type), gnat_constr = First_Elmt (Stored_Constraint (gnat_subtype)); Present (gnat_discrim); gnat_discrim = Next_Stored_Discriminant (gnat_discrim), gnat_constr = Next_Elmt (gnat_constr)) /* Ignore access discriminants. */ if (!Is_Access_Type (Etype (Node (gnat_constr)))) { tree gnu_field = gnat_to_gnu_field_decl (gnat_discrim); tree replacement = convert (TREE_TYPE (gnu_field), elaborate_expression (Node (gnat_constr), gnat_subtype, get_entity_char (gnat_discrim), definition, true, false)); subst_pair s = {gnu_field, replacement}; gnu_list.safe_push (s); } return gnu_list; } /* Scan all fields in QUAL_UNION_TYPE and return a list describing the variants of QUAL_UNION_TYPE that are still relevant after applying the substitutions described in SUBST_LIST. GNU_LIST is a pre-existing list to be prepended to the newly created entries. */ static vec build_variant_list (tree qual_union_type, vec subst_list, vec gnu_list) { tree gnu_field; for (gnu_field = TYPE_FIELDS (qual_union_type); gnu_field; gnu_field = DECL_CHAIN (gnu_field)) { tree qual = DECL_QUALIFIER (gnu_field); unsigned int i; subst_pair *s; FOR_EACH_VEC_ELT (subst_list, i, s) qual = SUBSTITUTE_IN_EXPR (qual, s->discriminant, s->replacement); /* If the new qualifier is not unconditionally false, its variant may still be accessed. */ if (!integer_zerop (qual)) { tree variant_type = TREE_TYPE (gnu_field), variant_subpart; variant_desc v = {variant_type, gnu_field, qual, NULL_TREE}; gnu_list.safe_push (v); /* Recurse on the variant subpart of the variant, if any. */ variant_subpart = get_variant_part (variant_type); if (variant_subpart) gnu_list = build_variant_list (TREE_TYPE (variant_subpart), subst_list, gnu_list); /* If the new qualifier is unconditionally true, the subsequent variants cannot be accessed. */ if (integer_onep (qual)) break; } } return gnu_list; } /* UINT_SIZE is a Uint giving the specified size for an object of GNU_TYPE corresponding to GNAT_OBJECT. If the size is valid, return an INTEGER_CST corresponding to its value. Otherwise, return NULL_TREE. KIND is set to VAR_DECL if we are specifying the size of an object, TYPE_DECL for the size of a type, and FIELD_DECL for the size of a field. COMPONENT_P is true if we are being called to process the Component_Size of GNAT_OBJECT; this is used only for error messages. ZERO_OK is true if a size of zero is permitted; if ZERO_OK is false, it means that a size of zero should be treated as an unspecified size. */ static tree validate_size (Uint uint_size, tree gnu_type, Entity_Id gnat_object, enum tree_code kind, bool component_p, bool zero_ok) { Node_Id gnat_error_node; tree type_size, size; /* Return 0 if no size was specified. */ if (uint_size == No_Uint) return NULL_TREE; /* Ignore a negative size since that corresponds to our back-annotation. */ if (UI_Lt (uint_size, Uint_0)) return NULL_TREE; /* Find the node to use for error messages. */ if ((Ekind (gnat_object) == E_Component || Ekind (gnat_object) == E_Discriminant) && Present (Component_Clause (gnat_object))) gnat_error_node = Last_Bit (Component_Clause (gnat_object)); else if (Present (Size_Clause (gnat_object))) gnat_error_node = Expression (Size_Clause (gnat_object)); else gnat_error_node = gnat_object; /* Get the size as an INTEGER_CST. Issue an error if a size was specified but cannot be represented in bitsizetype. */ size = UI_To_gnu (uint_size, bitsizetype); if (TREE_OVERFLOW (size)) { if (component_p) post_error_ne ("component size for& is too large", gnat_error_node, gnat_object); else post_error_ne ("size for& is too large", gnat_error_node, gnat_object); return NULL_TREE; } /* Ignore a zero size if it is not permitted. */ if (!zero_ok && integer_zerop (size)) return NULL_TREE; /* The size of objects is always a multiple of a byte. */ if (kind == VAR_DECL && !integer_zerop (size_binop (TRUNC_MOD_EXPR, size, bitsize_unit_node))) { if (component_p) post_error_ne ("component size for& is not a multiple of Storage_Unit", gnat_error_node, gnat_object); else post_error_ne ("size for& is not a multiple of Storage_Unit", gnat_error_node, gnat_object); return NULL_TREE; } /* If this is an integral type or a packed array type, the front-end has already verified the size, so we need not do it here (which would mean checking against the bounds). However, if this is an aliased object, it may not be smaller than the type of the object. */ if ((INTEGRAL_TYPE_P (gnu_type) || TYPE_IS_PACKED_ARRAY_TYPE_P (gnu_type)) && !(kind == VAR_DECL && Is_Aliased (gnat_object))) return size; /* If the object is a record that contains a template, add the size of the template to the specified size. */ if (TREE_CODE (gnu_type) == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (gnu_type)) size = size_binop (PLUS_EXPR, DECL_SIZE (TYPE_FIELDS (gnu_type)), size); if (kind == VAR_DECL /* If a type needs strict alignment, a component of this type in a packed record cannot be packed and thus uses the type size. */ || (kind == TYPE_DECL && Strict_Alignment (gnat_object))) type_size = TYPE_SIZE (gnu_type); else type_size = rm_size (gnu_type); /* Modify the size of a discriminated type to be the maximum size. */ if (type_size && CONTAINS_PLACEHOLDER_P (type_size)) type_size = max_size (type_size, true); /* If this is an access type or a fat pointer, the minimum size is that given by the smallest integral mode that's valid for pointers. */ if (TREE_CODE (gnu_type) == POINTER_TYPE || TYPE_IS_FAT_POINTER_P (gnu_type)) { machine_mode p_mode = GET_CLASS_NARROWEST_MODE (MODE_INT); while (!targetm.valid_pointer_mode (p_mode)) p_mode = GET_MODE_WIDER_MODE (p_mode); type_size = bitsize_int (GET_MODE_BITSIZE (p_mode)); } /* Issue an error either if the default size of the object isn't a constant or if the new size is smaller than it. */ if (TREE_CODE (type_size) != INTEGER_CST || TREE_OVERFLOW (type_size) || tree_int_cst_lt (size, type_size)) { if (component_p) post_error_ne_tree ("component size for& too small{, minimum allowed is ^}", gnat_error_node, gnat_object, type_size); else post_error_ne_tree ("size for& too small{, minimum allowed is ^}", gnat_error_node, gnat_object, type_size); return NULL_TREE; } return size; } /* Similarly, but both validate and process a value of RM size. This routine is only called for types. */ static void set_rm_size (Uint uint_size, tree gnu_type, Entity_Id gnat_entity) { Node_Id gnat_attr_node; tree old_size, size; /* Do nothing if no size was specified. */ if (uint_size == No_Uint) return; /* Ignore a negative size since that corresponds to our back-annotation. */ if (UI_Lt (uint_size, Uint_0)) return; /* Only issue an error if a Value_Size clause was explicitly given. Otherwise, we'd be duplicating an error on the Size clause. */ gnat_attr_node = Get_Attribute_Definition_Clause (gnat_entity, Attr_Value_Size); /* Get the size as an INTEGER_CST. Issue an error if a size was specified but cannot be represented in bitsizetype. */ size = UI_To_gnu (uint_size, bitsizetype); if (TREE_OVERFLOW (size)) { if (Present (gnat_attr_node)) post_error_ne ("Value_Size for& is too large", gnat_attr_node, gnat_entity); return; } /* Ignore a zero size unless a Value_Size clause exists, or a size clause exists, or this is an integer type, in which case the front-end will have always set it. */ if (No (gnat_attr_node) && integer_zerop (size) && !Has_Size_Clause (gnat_entity) && !Is_Discrete_Or_Fixed_Point_Type (gnat_entity)) return; old_size = rm_size (gnu_type); /* If the old size is self-referential, get the maximum size. */ if (CONTAINS_PLACEHOLDER_P (old_size)) old_size = max_size (old_size, true); /* Issue an error either if the old size of the object isn't a constant or if the new size is smaller than it. The front-end has already verified this for scalar and packed array types. */ if (TREE_CODE (old_size) != INTEGER_CST || TREE_OVERFLOW (old_size) || (AGGREGATE_TYPE_P (gnu_type) && !(TREE_CODE (gnu_type) == ARRAY_TYPE && TYPE_PACKED_ARRAY_TYPE_P (gnu_type)) && !(TYPE_IS_PADDING_P (gnu_type) && TREE_CODE (TREE_TYPE (TYPE_FIELDS (gnu_type))) == ARRAY_TYPE && TYPE_PACKED_ARRAY_TYPE_P (TREE_TYPE (TYPE_FIELDS (gnu_type)))) && tree_int_cst_lt (size, old_size))) { if (Present (gnat_attr_node)) post_error_ne_tree ("Value_Size for& too small{, minimum allowed is ^}", gnat_attr_node, gnat_entity, old_size); return; } /* Otherwise, set the RM size proper for integral types... */ if ((TREE_CODE (gnu_type) == INTEGER_TYPE && Is_Discrete_Or_Fixed_Point_Type (gnat_entity)) || (TREE_CODE (gnu_type) == ENUMERAL_TYPE || TREE_CODE (gnu_type) == BOOLEAN_TYPE)) SET_TYPE_RM_SIZE (gnu_type, size); /* ...or the Ada size for record and union types. */ else if (RECORD_OR_UNION_TYPE_P (gnu_type) && !TYPE_FAT_POINTER_P (gnu_type)) SET_TYPE_ADA_SIZE (gnu_type, size); } /* ALIGNMENT is a Uint giving the alignment specified for GNAT_ENTITY, a type or object whose present alignment is ALIGN. If this alignment is valid, return it. Otherwise, give an error and return ALIGN. */ static unsigned int validate_alignment (Uint alignment, Entity_Id gnat_entity, unsigned int align) { unsigned int max_allowed_alignment = get_target_maximum_allowed_alignment (); unsigned int new_align; Node_Id gnat_error_node; /* Don't worry about checking alignment if alignment was not specified by the source program and we already posted an error for this entity. */ if (Error_Posted (gnat_entity) && !Has_Alignment_Clause (gnat_entity)) return align; /* Post the error on the alignment clause if any. Note, for the implicit base type of an array type, the alignment clause is on the first subtype. */ if (Present (Alignment_Clause (gnat_entity))) gnat_error_node = Expression (Alignment_Clause (gnat_entity)); else if (Is_Itype (gnat_entity) && Is_Array_Type (gnat_entity) && Etype (gnat_entity) == gnat_entity && Present (Alignment_Clause (First_Subtype (gnat_entity)))) gnat_error_node = Expression (Alignment_Clause (First_Subtype (gnat_entity))); else gnat_error_node = gnat_entity; /* Within GCC, an alignment is an integer, so we must make sure a value is specified that fits in that range. Also, there is an upper bound to alignments we can support/allow. */ if (!UI_Is_In_Int_Range (alignment) || ((new_align = UI_To_Int (alignment)) > max_allowed_alignment)) post_error_ne_num ("largest supported alignment for& is ^", gnat_error_node, gnat_entity, max_allowed_alignment); else if (!(Present (Alignment_Clause (gnat_entity)) && From_At_Mod (Alignment_Clause (gnat_entity))) && new_align * BITS_PER_UNIT < align) { unsigned int double_align; bool is_capped_double, align_clause; /* If the default alignment of "double" or larger scalar types is specifically capped and the new alignment is above the cap, do not post an error and change the alignment only if there is an alignment clause; this makes it possible to have the associated GCC type overaligned by default for performance reasons. */ if ((double_align = double_float_alignment) > 0) { Entity_Id gnat_type = Is_Type (gnat_entity) ? gnat_entity : Etype (gnat_entity); is_capped_double = is_double_float_or_array (gnat_type, &align_clause); } else if ((double_align = double_scalar_alignment) > 0) { Entity_Id gnat_type = Is_Type (gnat_entity) ? gnat_entity : Etype (gnat_entity); is_capped_double = is_double_scalar_or_array (gnat_type, &align_clause); } else is_capped_double = align_clause = false; if (is_capped_double && new_align >= double_align) { if (align_clause) align = new_align * BITS_PER_UNIT; } else { if (is_capped_double) align = double_align * BITS_PER_UNIT; post_error_ne_num ("alignment for& must be at least ^", gnat_error_node, gnat_entity, align / BITS_PER_UNIT); } } else { new_align = (new_align > 0 ? new_align * BITS_PER_UNIT : 1); if (new_align > align) align = new_align; } return align; } /* Verify that TYPE is something we can implement atomically. If not, issue an error for GNAT_ENTITY. COMPONENT_P is true if we are being called to process a component type. */ static void check_ok_for_atomic_type (tree type, Entity_Id gnat_entity, bool component_p) { Node_Id gnat_error_point = gnat_entity; Node_Id gnat_node; machine_mode mode; enum mode_class mclass; unsigned int align; tree size; /* If this is an anonymous base type, nothing to check, the error will be reported on the source type if need be. */ if (!Comes_From_Source (gnat_entity)) return; mode = TYPE_MODE (type); mclass = GET_MODE_CLASS (mode); align = TYPE_ALIGN (type); size = TYPE_SIZE (type); /* Consider all aligned floating-point types atomic and any aligned types that are represented by integers no wider than a machine word. */ if ((mclass == MODE_FLOAT || ((mclass == MODE_INT || mclass == MODE_PARTIAL_INT) && GET_MODE_BITSIZE (mode) <= BITS_PER_WORD)) && align >= GET_MODE_ALIGNMENT (mode)) return; /* For the moment, also allow anything that has an alignment equal to its size and which is smaller than a word. */ if (size && TREE_CODE (size) == INTEGER_CST && compare_tree_int (size, align) == 0 && align <= BITS_PER_WORD) return; for (gnat_node = First_Rep_Item (gnat_entity); Present (gnat_node); gnat_node = Next_Rep_Item (gnat_node)) if (Nkind (gnat_node) == N_Pragma) { unsigned char pragma_id = Get_Pragma_Id (Chars (Pragma_Identifier (gnat_node))); if ((pragma_id == Pragma_Atomic && !component_p) || (pragma_id == Pragma_Atomic_Components && component_p)) { gnat_error_point = First (Pragma_Argument_Associations (gnat_node)); break; } } if (component_p) post_error_ne ("atomic access to component of & cannot be guaranteed", gnat_error_point, gnat_entity); else if (Is_Volatile_Full_Access (gnat_entity)) post_error_ne ("volatile full access to & cannot be guaranteed", gnat_error_point, gnat_entity); else post_error_ne ("atomic access to & cannot be guaranteed", gnat_error_point, gnat_entity); } /* Helper for the intrin compatibility checks family. Evaluate whether two types are definitely incompatible. */ static bool intrin_types_incompatible_p (tree t1, tree t2) { enum tree_code code; if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2)) return false; if (TYPE_MODE (t1) != TYPE_MODE (t2)) return true; if (TREE_CODE (t1) != TREE_CODE (t2)) return true; code = TREE_CODE (t1); switch (code) { case INTEGER_TYPE: case REAL_TYPE: return TYPE_PRECISION (t1) != TYPE_PRECISION (t2); case POINTER_TYPE: case REFERENCE_TYPE: /* Assume designated types are ok. We'd need to account for char * and void * variants to do better, which could rapidly get messy and isn't clearly worth the effort. */ return false; default: break; } return false; } /* Helper for intrin_profiles_compatible_p, to perform compatibility checks on the Ada/builtin argument lists for the INB binding. */ static bool intrin_arglists_compatible_p (intrin_binding_t * inb) { function_args_iterator ada_iter, btin_iter; function_args_iter_init (&ada_iter, inb->ada_fntype); function_args_iter_init (&btin_iter, inb->btin_fntype); /* Sequence position of the last argument we checked. */ int argpos = 0; while (1) { tree ada_type = function_args_iter_cond (&ada_iter); tree btin_type = function_args_iter_cond (&btin_iter); /* If we've exhausted both lists simultaneously, we're done. */ if (ada_type == NULL_TREE && btin_type == NULL_TREE) break; /* If one list is shorter than the other, they fail to match. */ if (ada_type == NULL_TREE || btin_type == NULL_TREE) return false; /* If we're done with the Ada args and not with the internal builtin args, or the other way around, complain. */ if (ada_type == void_type_node && btin_type != void_type_node) { post_error ("?Ada arguments list too short!", inb->gnat_entity); return false; } if (btin_type == void_type_node && ada_type != void_type_node) { post_error_ne_num ("?Ada arguments list too long ('> ^)!", inb->gnat_entity, inb->gnat_entity, argpos); return false; } /* Otherwise, check that types match for the current argument. */ argpos ++; if (intrin_types_incompatible_p (ada_type, btin_type)) { post_error_ne_num ("?intrinsic binding type mismatch on argument ^!", inb->gnat_entity, inb->gnat_entity, argpos); return false; } function_args_iter_next (&ada_iter); function_args_iter_next (&btin_iter); } return true; } /* Helper for intrin_profiles_compatible_p, to perform compatibility checks on the Ada/builtin return values for the INB binding. */ static bool intrin_return_compatible_p (intrin_binding_t * inb) { tree ada_return_type = TREE_TYPE (inb->ada_fntype); tree btin_return_type = TREE_TYPE (inb->btin_fntype); /* Accept function imported as procedure, common and convenient. */ if (VOID_TYPE_P (ada_return_type) && !VOID_TYPE_P (btin_return_type)) return true; /* If return type is Address (integer type), map it to void *. */ if (Is_Descendent_Of_Address (Etype (inb->gnat_entity))) ada_return_type = ptr_type_node; /* Check return types compatibility otherwise. Note that this handles void/void as well. */ if (intrin_types_incompatible_p (btin_return_type, ada_return_type)) { post_error ("?intrinsic binding type mismatch on return value!", inb->gnat_entity); return false; } return true; } /* Check and return whether the Ada and gcc builtin profiles bound by INB are compatible. Issue relevant warnings when they are not. This is intended as a light check to diagnose the most obvious cases, not as a full fledged type compatibility predicate. It is the programmer's responsibility to ensure correctness of the Ada declarations in Imports, especially when binding straight to a compiler internal. */ static bool intrin_profiles_compatible_p (intrin_binding_t * inb) { /* Check compatibility on return values and argument lists, each responsible for posting warnings as appropriate. Ensure use of the proper sloc for this purpose. */ bool arglists_compatible_p, return_compatible_p; location_t saved_location = input_location; Sloc_to_locus (Sloc (inb->gnat_entity), &input_location); return_compatible_p = intrin_return_compatible_p (inb); arglists_compatible_p = intrin_arglists_compatible_p (inb); input_location = saved_location; return return_compatible_p && arglists_compatible_p; } /* Return a FIELD_DECL node modeled on OLD_FIELD. FIELD_TYPE is its type and RECORD_TYPE is the type of the parent. If SIZE is nonzero, it is the specified size for this field. POS_LIST is a position list describing the layout of OLD_FIELD and SUBST_LIST a substitution list to be applied to this layout. */ static tree create_field_decl_from (tree old_field, tree field_type, tree record_type, tree size, tree pos_list, vec subst_list) { tree t = TREE_VALUE (purpose_member (old_field, pos_list)); tree pos = TREE_VEC_ELT (t, 0), bitpos = TREE_VEC_ELT (t, 2); unsigned int offset_align = tree_to_uhwi (TREE_VEC_ELT (t, 1)); tree new_pos, new_field; unsigned int i; subst_pair *s; if (CONTAINS_PLACEHOLDER_P (pos)) FOR_EACH_VEC_ELT (subst_list, i, s) pos = SUBSTITUTE_IN_EXPR (pos, s->discriminant, s->replacement); /* If the position is now a constant, we can set it as the position of the field when we make it. Otherwise, we need to deal with it specially. */ if (TREE_CONSTANT (pos)) new_pos = bit_from_pos (pos, bitpos); else new_pos = NULL_TREE; new_field = create_field_decl (DECL_NAME (old_field), field_type, record_type, size, new_pos, DECL_PACKED (old_field), !DECL_NONADDRESSABLE_P (old_field)); if (!new_pos) { normalize_offset (&pos, &bitpos, offset_align); /* Finalize the position. */ DECL_FIELD_OFFSET (new_field) = variable_size (pos); DECL_FIELD_BIT_OFFSET (new_field) = bitpos; SET_DECL_OFFSET_ALIGN (new_field, offset_align); DECL_SIZE (new_field) = size; DECL_SIZE_UNIT (new_field) = convert (sizetype, size_binop (CEIL_DIV_EXPR, size, bitsize_unit_node)); layout_decl (new_field, DECL_OFFSET_ALIGN (new_field)); } DECL_INTERNAL_P (new_field) = DECL_INTERNAL_P (old_field); SET_DECL_ORIGINAL_FIELD_TO_FIELD (new_field, old_field); DECL_DISCRIMINANT_NUMBER (new_field) = DECL_DISCRIMINANT_NUMBER (old_field); TREE_THIS_VOLATILE (new_field) = TREE_THIS_VOLATILE (old_field); return new_field; } /* Create the REP part of RECORD_TYPE with REP_TYPE. If MIN_SIZE is nonzero, it is the minimal size the REP_PART must have. */ static tree create_rep_part (tree rep_type, tree record_type, tree min_size) { tree field; if (min_size && !tree_int_cst_lt (TYPE_SIZE (rep_type), min_size)) min_size = NULL_TREE; field = create_field_decl (get_identifier ("REP"), rep_type, record_type, min_size, NULL_TREE, 0, 1); DECL_INTERNAL_P (field) = 1; return field; } /* Return the REP part of RECORD_TYPE, if any. Otherwise return NULL. */ static tree get_rep_part (tree record_type) { tree field = TYPE_FIELDS (record_type); /* The REP part is the first field, internal, another record, and its name starts with an 'R'. */ if (field && DECL_INTERNAL_P (field) && TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE && IDENTIFIER_POINTER (DECL_NAME (field)) [0] == 'R') return field; return NULL_TREE; } /* Return the variant part of RECORD_TYPE, if any. Otherwise return NULL. */ tree get_variant_part (tree record_type) { tree field; /* The variant part is the only internal field that is a qualified union. */ for (field = TYPE_FIELDS (record_type); field; field = DECL_CHAIN (field)) if (DECL_INTERNAL_P (field) && TREE_CODE (TREE_TYPE (field)) == QUAL_UNION_TYPE) return field; return NULL_TREE; } /* Return a new variant part modeled on OLD_VARIANT_PART. VARIANT_LIST is the list of variants to be used and RECORD_TYPE is the type of the parent. POS_LIST is a position list describing the layout of fields present in OLD_VARIANT_PART and SUBST_LIST a substitution list to be applied to this layout. */ static tree create_variant_part_from (tree old_variant_part, vec variant_list, tree record_type, tree pos_list, vec subst_list) { tree offset = DECL_FIELD_OFFSET (old_variant_part); tree old_union_type = TREE_TYPE (old_variant_part); tree new_union_type, new_variant_part; tree union_field_list = NULL_TREE; variant_desc *v; unsigned int i; /* First create the type of the variant part from that of the old one. */ new_union_type = make_node (QUAL_UNION_TYPE); TYPE_NAME (new_union_type) = concat_name (TYPE_NAME (record_type), IDENTIFIER_POINTER (DECL_NAME (old_variant_part))); /* If the position of the variant part is constant, subtract it from the size of the type of the parent to get the new size. This manual CSE reduces the code size when not optimizing. */ if (TREE_CODE (offset) == INTEGER_CST) { tree bitpos = DECL_FIELD_BIT_OFFSET (old_variant_part); tree first_bit = bit_from_pos (offset, bitpos); TYPE_SIZE (new_union_type) = size_binop (MINUS_EXPR, TYPE_SIZE (record_type), first_bit); TYPE_SIZE_UNIT (new_union_type) = size_binop (MINUS_EXPR, TYPE_SIZE_UNIT (record_type), byte_from_pos (offset, bitpos)); SET_TYPE_ADA_SIZE (new_union_type, size_binop (MINUS_EXPR, TYPE_ADA_SIZE (record_type), first_bit)); TYPE_ALIGN (new_union_type) = TYPE_ALIGN (old_union_type); relate_alias_sets (new_union_type, old_union_type, ALIAS_SET_COPY); } else copy_and_substitute_in_size (new_union_type, old_union_type, subst_list); /* Now finish up the new variants and populate the union type. */ FOR_EACH_VEC_ELT_REVERSE (variant_list, i, v) { tree old_field = v->field, new_field; tree old_variant, old_variant_subpart, new_variant, field_list; /* Skip variants that don't belong to this nesting level. */ if (DECL_CONTEXT (old_field) != old_union_type) continue; /* Retrieve the list of fields already added to the new variant. */ new_variant = v->new_type; field_list = TYPE_FIELDS (new_variant); /* If the old variant had a variant subpart, we need to create a new variant subpart and add it to the field list. */ old_variant = v->type; old_variant_subpart = get_variant_part (old_variant); if (old_variant_subpart) { tree new_variant_subpart = create_variant_part_from (old_variant_subpart, variant_list, new_variant, pos_list, subst_list); DECL_CHAIN (new_variant_subpart) = field_list; field_list = new_variant_subpart; } /* Finish up the new variant and create the field. No need for debug info thanks to the XVS type. */ finish_record_type (new_variant, nreverse (field_list), 2, false); compute_record_mode (new_variant); create_type_decl (TYPE_NAME (new_variant), new_variant, true, false, Empty); new_field = create_field_decl_from (old_field, new_variant, new_union_type, TYPE_SIZE (new_variant), pos_list, subst_list); DECL_QUALIFIER (new_field) = v->qual; DECL_INTERNAL_P (new_field) = 1; DECL_CHAIN (new_field) = union_field_list; union_field_list = new_field; } /* Finish up the union type and create the variant part. No need for debug info thanks to the XVS type. Note that we don't reverse the field list because VARIANT_LIST has been traversed in reverse order. */ finish_record_type (new_union_type, union_field_list, 2, false); compute_record_mode (new_union_type); create_type_decl (TYPE_NAME (new_union_type), new_union_type, true, false, Empty); new_variant_part = create_field_decl_from (old_variant_part, new_union_type, record_type, TYPE_SIZE (new_union_type), pos_list, subst_list); DECL_INTERNAL_P (new_variant_part) = 1; /* With multiple discriminants it is possible for an inner variant to be statically selected while outer ones are not; in this case, the list of fields of the inner variant is not flattened and we end up with a qualified union with a single member. Drop the useless container. */ if (!DECL_CHAIN (union_field_list)) { DECL_CONTEXT (union_field_list) = record_type; DECL_FIELD_OFFSET (union_field_list) = DECL_FIELD_OFFSET (new_variant_part); DECL_FIELD_BIT_OFFSET (union_field_list) = DECL_FIELD_BIT_OFFSET (new_variant_part); SET_DECL_OFFSET_ALIGN (union_field_list, DECL_OFFSET_ALIGN (new_variant_part)); new_variant_part = union_field_list; } return new_variant_part; } /* Copy the size (and alignment and alias set) from OLD_TYPE to NEW_TYPE, which are both RECORD_TYPE, after applying the substitutions described in SUBST_LIST. */ static void copy_and_substitute_in_size (tree new_type, tree old_type, vec subst_list) { unsigned int i; subst_pair *s; TYPE_SIZE (new_type) = TYPE_SIZE (old_type); TYPE_SIZE_UNIT (new_type) = TYPE_SIZE_UNIT (old_type); SET_TYPE_ADA_SIZE (new_type, TYPE_ADA_SIZE (old_type)); TYPE_ALIGN (new_type) = TYPE_ALIGN (old_type); relate_alias_sets (new_type, old_type, ALIAS_SET_COPY); if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE (new_type))) FOR_EACH_VEC_ELT (subst_list, i, s) TYPE_SIZE (new_type) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (new_type), s->discriminant, s->replacement); if (CONTAINS_PLACEHOLDER_P (TYPE_SIZE_UNIT (new_type))) FOR_EACH_VEC_ELT (subst_list, i, s) TYPE_SIZE_UNIT (new_type) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (new_type), s->discriminant, s->replacement); if (CONTAINS_PLACEHOLDER_P (TYPE_ADA_SIZE (new_type))) FOR_EACH_VEC_ELT (subst_list, i, s) SET_TYPE_ADA_SIZE (new_type, SUBSTITUTE_IN_EXPR (TYPE_ADA_SIZE (new_type), s->discriminant, s->replacement)); /* Finalize the size. */ TYPE_SIZE (new_type) = variable_size (TYPE_SIZE (new_type)); TYPE_SIZE_UNIT (new_type) = variable_size (TYPE_SIZE_UNIT (new_type)); } /* Add a parallel type to GNU_TYPE, the translation of GNAT_ENTITY, which is the implementation type of a packed array type (Is_Packed_Array_Impl_Type). The parallel type is the original array type if it has been translated. */ static void add_parallel_type_for_packed_array (tree gnu_type, Entity_Id gnat_entity) { Entity_Id gnat_original_array_type = Underlying_Type (Original_Array_Type (gnat_entity)); tree gnu_original_array_type; if (!present_gnu_tree (gnat_original_array_type)) return; gnu_original_array_type = gnat_to_gnu_type (gnat_original_array_type); if (TYPE_IS_DUMMY_P (gnu_original_array_type)) return; add_parallel_type (gnu_type, gnu_original_array_type); } /* Given a type T, a FIELD_DECL F, and a replacement value R, return a type with all size expressions that contain F in a PLACEHOLDER_EXPR updated by replacing F with R. The function doesn't update the layout of the type, i.e. it assumes that the substitution is purely formal. That's why the replacement value R must itself contain a PLACEHOLDER_EXPR. */ tree substitute_in_type (tree t, tree f, tree r) { tree nt; gcc_assert (CONTAINS_PLACEHOLDER_P (r)); switch (TREE_CODE (t)) { case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE: case REAL_TYPE: /* First the domain types of arrays. */ if (CONTAINS_PLACEHOLDER_P (TYPE_GCC_MIN_VALUE (t)) || CONTAINS_PLACEHOLDER_P (TYPE_GCC_MAX_VALUE (t))) { tree low = SUBSTITUTE_IN_EXPR (TYPE_GCC_MIN_VALUE (t), f, r); tree high = SUBSTITUTE_IN_EXPR (TYPE_GCC_MAX_VALUE (t), f, r); if (low == TYPE_GCC_MIN_VALUE (t) && high == TYPE_GCC_MAX_VALUE (t)) return t; nt = copy_type (t); TYPE_GCC_MIN_VALUE (nt) = low; TYPE_GCC_MAX_VALUE (nt) = high; if (TREE_CODE (t) == INTEGER_TYPE && TYPE_INDEX_TYPE (t)) SET_TYPE_INDEX_TYPE (nt, substitute_in_type (TYPE_INDEX_TYPE (t), f, r)); return nt; } /* Then the subtypes. */ if (CONTAINS_PLACEHOLDER_P (TYPE_RM_MIN_VALUE (t)) || CONTAINS_PLACEHOLDER_P (TYPE_RM_MAX_VALUE (t))) { tree low = SUBSTITUTE_IN_EXPR (TYPE_RM_MIN_VALUE (t), f, r); tree high = SUBSTITUTE_IN_EXPR (TYPE_RM_MAX_VALUE (t), f, r); if (low == TYPE_RM_MIN_VALUE (t) && high == TYPE_RM_MAX_VALUE (t)) return t; nt = copy_type (t); SET_TYPE_RM_MIN_VALUE (nt, low); SET_TYPE_RM_MAX_VALUE (nt, high); return nt; } return t; case COMPLEX_TYPE: nt = substitute_in_type (TREE_TYPE (t), f, r); if (nt == TREE_TYPE (t)) return t; return build_complex_type (nt); case FUNCTION_TYPE: /* These should never show up here. */ gcc_unreachable (); case ARRAY_TYPE: { tree component = substitute_in_type (TREE_TYPE (t), f, r); tree domain = substitute_in_type (TYPE_DOMAIN (t), f, r); if (component == TREE_TYPE (t) && domain == TYPE_DOMAIN (t)) return t; nt = build_nonshared_array_type (component, domain); TYPE_ALIGN (nt) = TYPE_ALIGN (t); TYPE_USER_ALIGN (nt) = TYPE_USER_ALIGN (t); SET_TYPE_MODE (nt, TYPE_MODE (t)); TYPE_SIZE (nt) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (t), f, r); TYPE_SIZE_UNIT (nt) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (t), f, r); TYPE_NONALIASED_COMPONENT (nt) = TYPE_NONALIASED_COMPONENT (t); TYPE_MULTI_ARRAY_P (nt) = TYPE_MULTI_ARRAY_P (t); TYPE_CONVENTION_FORTRAN_P (nt) = TYPE_CONVENTION_FORTRAN_P (t); return nt; } case RECORD_TYPE: case UNION_TYPE: case QUAL_UNION_TYPE: { bool changed_field = false; tree field; /* Start out with no fields, make new fields, and chain them in. If we haven't actually changed the type of any field, discard everything we've done and return the old type. */ nt = copy_type (t); TYPE_FIELDS (nt) = NULL_TREE; for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field)) { tree new_field = copy_node (field), new_n; new_n = substitute_in_type (TREE_TYPE (field), f, r); if (new_n != TREE_TYPE (field)) { TREE_TYPE (new_field) = new_n; changed_field = true; } new_n = SUBSTITUTE_IN_EXPR (DECL_FIELD_OFFSET (field), f, r); if (new_n != DECL_FIELD_OFFSET (field)) { DECL_FIELD_OFFSET (new_field) = new_n; changed_field = true; } /* Do the substitution inside the qualifier, if any. */ if (TREE_CODE (t) == QUAL_UNION_TYPE) { new_n = SUBSTITUTE_IN_EXPR (DECL_QUALIFIER (field), f, r); if (new_n != DECL_QUALIFIER (field)) { DECL_QUALIFIER (new_field) = new_n; changed_field = true; } } DECL_CONTEXT (new_field) = nt; SET_DECL_ORIGINAL_FIELD_TO_FIELD (new_field, field); DECL_CHAIN (new_field) = TYPE_FIELDS (nt); TYPE_FIELDS (nt) = new_field; } if (!changed_field) return t; TYPE_FIELDS (nt) = nreverse (TYPE_FIELDS (nt)); TYPE_SIZE (nt) = SUBSTITUTE_IN_EXPR (TYPE_SIZE (t), f, r); TYPE_SIZE_UNIT (nt) = SUBSTITUTE_IN_EXPR (TYPE_SIZE_UNIT (t), f, r); SET_TYPE_ADA_SIZE (nt, SUBSTITUTE_IN_EXPR (TYPE_ADA_SIZE (t), f, r)); return nt; } default: return t; } } /* Return the RM size of GNU_TYPE. This is the actual number of bits needed to represent the object. */ tree rm_size (tree gnu_type) { /* For integral types, we store the RM size explicitly. */ if (INTEGRAL_TYPE_P (gnu_type) && TYPE_RM_SIZE (gnu_type)) return TYPE_RM_SIZE (gnu_type); /* Return the RM size of the actual data plus the size of the template. */ if (TREE_CODE (gnu_type) == RECORD_TYPE && TYPE_CONTAINS_TEMPLATE_P (gnu_type)) return size_binop (PLUS_EXPR, rm_size (TREE_TYPE (DECL_CHAIN (TYPE_FIELDS (gnu_type)))), DECL_SIZE (TYPE_FIELDS (gnu_type))); /* For record or union types, we store the size explicitly. */ if (RECORD_OR_UNION_TYPE_P (gnu_type) && !TYPE_FAT_POINTER_P (gnu_type) && TYPE_ADA_SIZE (gnu_type)) return TYPE_ADA_SIZE (gnu_type); /* For other types, this is just the size. */ return TYPE_SIZE (gnu_type); } /* Return the name to be used for GNAT_ENTITY. If a type, create a fully-qualified name, possibly with type information encoding. Otherwise, return the name. */ static const char * get_entity_char (Entity_Id gnat_entity) { Get_Encoded_Name (gnat_entity); return ggc_strdup (Name_Buffer); } tree get_entity_name (Entity_Id gnat_entity) { Get_Encoded_Name (gnat_entity); return get_identifier_with_length (Name_Buffer, Name_Len); } /* Return an identifier representing the external name to be used for GNAT_ENTITY. If SUFFIX is specified, the name is followed by "___" and the specified suffix. */ tree create_concat_name (Entity_Id gnat_entity, const char *suffix) { const Entity_Kind kind = Ekind (gnat_entity); const bool has_suffix = (suffix != NULL); String_Template temp = {1, has_suffix ? strlen (suffix) : 0}; String_Pointer sp = {suffix, &temp}; Get_External_Name (gnat_entity, has_suffix, sp); /* A variable using the Stdcall convention lives in a DLL. We adjust its name to use the jump table, the _imp__NAME contains the address for the NAME variable. */ if ((kind == E_Variable || kind == E_Constant) && Has_Stdcall_Convention (gnat_entity)) { const int len = strlen (STDCALL_PREFIX) + Name_Len; char *new_name = (char *) alloca (len + 1); strcpy (new_name, STDCALL_PREFIX); strcat (new_name, Name_Buffer); return get_identifier_with_length (new_name, len); } return get_identifier_with_length (Name_Buffer, Name_Len); } /* Given GNU_NAME, an IDENTIFIER_NODE containing a name and SUFFIX, a string, return a new IDENTIFIER_NODE that is the concatenation of the name followed by "___" and the specified suffix. */ tree concat_name (tree gnu_name, const char *suffix) { const int len = IDENTIFIER_LENGTH (gnu_name) + 3 + strlen (suffix); char *new_name = (char *) alloca (len + 1); strcpy (new_name, IDENTIFIER_POINTER (gnu_name)); strcat (new_name, "___"); strcat (new_name, suffix); return get_identifier_with_length (new_name, len); } /* Initialize data structures of the decl.c module. */ void init_gnat_decl (void) { /* Initialize the cache of annotated values. */ annotate_value_cache = hash_table::create_ggc (512); } /* Destroy data structures of the decl.c module. */ void destroy_gnat_decl (void) { /* Destroy the cache of annotated values. */ annotate_value_cache->empty (); annotate_value_cache = NULL; } #include "gt-ada-decl.h"