/* Callgraph based intraprocedural optimizations. Copyright (C) 2003, 2004 Free Software Foundation, Inc. Contributed by Jan Hubicka This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GCC is distributed in the hope that it will be useful, but WITHOUT 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 COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* This module implements main driver of compilation process as well as few basic intraprocedural optimizers. The main scope of this file is to act as an interface in between tree based frontends and the backend (and middle end) The front-end is supposed to use following functionality: - cgraph_finalize_function This function is called once front-end has parsed whole body of function and it is certain that the function body nor the declaration will change. (There is one exception needed for implementing GCC extern inline function.) - cgraph_varpool_finalize_variable This function has same behavior as the above but is used for static variables. - cgraph_finalize_compilation_unit This function is called once compilation unit is finalized and it will no longer change. In the unit-at-a-time the call-graph construction and local function analysis takes place here. Bodies of unreachable functions are released to conserve memory usage. ??? The compilation unit in this point of view should be compilation unit as defined by the language - for instance C frontend allows multiple compilation units to be parsed at once and it should call function each time parsing is done so we save memory. - cgraph_optimize In this unit-at-a-time compilation the intra procedural analysis takes place here. In particular the static functions whose address is never taken are marked as local. Backend can then use this information to modify calling conventions, do better inlining or similar optimizations. - cgraph_assemble_pending_functions - cgraph_varpool_assemble_pending_variables In non-unit-at-a-time mode these functions can be used to force compilation of functions or variables that are known to be needed at given stage of compilation - cgraph_mark_needed_node - cgraph_varpool_mark_needed_node When function or variable is referenced by some hidden way (for instance via assembly code and marked by attribute "used"), the call-graph data structure must be updated accordingly by this function. - analyze_expr callback This function is responsible for lowering tree nodes not understood by generic code into understandable ones or alternatively marking callgraph and varpool nodes referenced by the as needed. ??? On the tree-ssa genericizing should take place here and we will avoid need for these hooks (replacing them by genericizing hook) - expand_function callback This function is used to expand function and pass it into RTL back-end. Front-end should not make any assumptions about when this function can be called. In particular cgraph_assemble_pending_functions, cgraph_varpool_assemble_pending_variables, cgraph_finalize_function, cgraph_varpool_finalize_function, cgraph_optimize can cause arbitrarily previously finalized functions to be expanded. We implement two compilation modes. - unit-at-a-time: In this mode analyzing of all functions is deferred to cgraph_finalize_compilation_unit and expansion into cgraph_optimize. In cgraph_finalize_compilation_unit the reachable functions are analyzed. During analysis the call-graph edges from reachable functions are constructed and their destinations are marked as reachable. References to functions and variables are discovered too and variables found to be needed output to the assembly file. Via mark_referenced call in assemble_variable functions referenced by static variables are noticed too. The intra-procedural information is produced and it's existence indicated by global_info_ready. Once this flag is set it is impossible to change function from !reachable to reachable and thus assemble_variable no longer call mark_referenced. Finally the call-graph is topologically sorted and all reachable functions that has not been completely inlined or are not external are output. ??? It is possible that reference to function or variable is optimized out. We can not deal with this nicely because topological order is not suitable for it. For tree-ssa we may consider another pass doing optimization and re-discovering reachable functions. ??? Reorganize code so variables are output very last and only if they really has been referenced by produced code, so we catch more cases where reference has been optimized out. - non-unit-at-a-time All functions are variables are output as early as possible to conserve memory consumption. This may or may not result in less memory used but it is still needed for some legacy code that rely on particular ordering of things output from the compiler. Varpool data structures are not used and variables are output directly. Functions are output early using call of cgraph_assemble_pending_function from cgraph_finalize_function. The decision on whether function is needed is made more conservative so uninlininable static functions are needed too. During the call-graph construction the edge destinations are not marked as reachable and it is completely relied upn assemble_variable to mark them. Inlining decision heuristics ??? Move this to separate file after tree-ssa merge. We separate inlining decisions from the inliner itself and store it inside callgraph as so called inline plan. Refer to cgraph.c documentation about particular representation of inline plans in the callgraph The implementation of particular heuristics is separated from the rest of code to make it easier to replace it with more complicated implementation in the future. The rest of inlining code acts as a library aimed to modify the callgraph and verify that the parameters on code size growth fits. To mark given call inline, use cgraph_mark_inline function, the verification is performed by cgraph_default_inline_p and cgraph_check_inline_limits. The heuristics implements simple knapsack style algorithm ordering all functions by their "profitability" (estimated by code size growth) and inlining them in priority order. cgraph_decide_inlining implements heuristics taking whole callgraph into account, while cgraph_decide_inlining_incrementally considers only one function at a time and is used in non-unit-at-a-time mode. */ /* Additionally this file gathers information about how local statics are used. This is done in cgraph_characterize_statics. After the call graph has been built, each function is analyzed to determine which local static variables are either read or written or have their address taken. Any local static that has its address taken is removed from consideration. Once the local read and writes are determined, a transitive closure of this information is performed over the call graph to determine the worst case set of side effects of each call. In a later part of the compiler, these local and global sets are examined to make the call clobbering less traumatic both with respect to aliasing and to code generation. */ #include "config.h" #include "system.h" #include "coretypes.h" #include "tm.h" #include "tree.h" #include "rtl.h" #include "tree-flow.h" #include "tree-inline.h" #include "langhooks.h" #include "pointer-set.h" #include "toplev.h" #include "flags.h" #include "ggc.h" #include "debug.h" #include "target.h" #include "cgraph.h" #include "diagnostic.h" #include "timevar.h" #include "params.h" #include "fibheap.h" #include "c-common.h" #include "intl.h" #include "function.h" #include "tree-gimple.h" #define INSNS_PER_CALL 10 static void cgraph_expand_all_functions (void); static void cgraph_mark_functions_to_output (void); static void cgraph_expand_function (struct cgraph_node *); static tree record_call_1 (tree *, int *, void *); static void cgraph_mark_local_and_external_functions (void); static bool cgraph_default_inline_p (struct cgraph_node *n); static void cgraph_analyze_function (struct cgraph_node *node); static void cgraph_decide_inlining_incrementally (struct cgraph_node *); /* Statistics we collect about inlining algorithm. */ static int ncalls_inlined; static int nfunctions_inlined; static int initial_insns; static int overall_insns; /* Records tree nodes seen in cgraph_create_edges. Simply using walk_tree_without_duplicates doesn't guarantee each node is visited once because it gets a new htab upon each recursive call from record_calls_1. */ static struct pointer_set_t *visited_nodes; static FILE *cgraph_dump_file; /* These splay trees contain all of the static variables that are being considered by the compilation level alias analysis. For module_at_a_time compilation, this is the set of static but not public variables. Any variables that either have their address taken or participate in otherwise unsavory operations are deleted from this list. */ static GTY((param1_is(tree), param2_is(tree))) splay_tree static_vars_to_consider_by_tree; /* FIXME -- PROFILE-RESTRUCTURE: change comment from DECL_UID to var-ann. */ /* same as above but indexed by DECL_UID */ static GTY((param1_is(int), param2_is(tree))) splay_tree static_vars_to_consider_by_uid; /* This bitmap is used to knock out the module static variables whose addresses have been taken and passed around. This is indexed by uid. */ static bitmap module_statics_escape; /* FIXME -- PROFILE-RESTRUCTURE: change comment from DECL_UID to var-ann. */ /* A bit is set for every module static we are considering and is indexed by DECL_UID. This is ored into the local info when asm code is found that clobbers all memory. */ static GTY(()) bitmap all_module_statics; /* Holds the value of "memory". */ static tree memory_identifier; /* Determine if function DECL is needed. That is, visible to something either outside this translation unit, something magic in the system configury, or (if not doing unit-at-a-time) to something we havn't seen yet. */ static bool decide_is_function_needed (struct cgraph_node *node, tree decl) { tree origin; /* If we decided it was needed before, but at the time we didn't have the body of the function available, then it's still needed. We have to go back and re-check its dependencies now. */ if (node->needed) return true; /* Externally visible functions must be output. The exception is COMDAT functions that must be output only when they are needed. */ if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl) && !DECL_EXTERNAL (decl)) return true; /* Constructors and destructors are reachable from the runtime by some mechanism. */ if (DECL_STATIC_CONSTRUCTOR (decl) || DECL_STATIC_DESTRUCTOR (decl)) return true; /* If the user told us it is used, then it must be so. */ if (lookup_attribute ("used", DECL_ATTRIBUTES (decl))) return true; /* ??? If the assembler name is set by hand, it is possible to assemble the name later after finalizing the function and the fact is noticed in assemble_name then. This is arguably a bug. */ if (DECL_ASSEMBLER_NAME_SET_P (decl) && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))) return true; if (flag_unit_at_a_time) return false; /* If not doing unit at a time, then we'll only defer this function if its marked for inlining. Otherwise we want to emit it now. */ /* "extern inline" functions are never output locally. */ if (DECL_EXTERNAL (decl)) return false; /* Nested functions of extern inline function shall not be emit unless we inlined the origin. */ for (origin = decl_function_context (decl); origin; origin = decl_function_context (origin)) if (DECL_EXTERNAL (origin)) return false; /* We want to emit COMDAT functions only when absolutely necessary. */ if (DECL_COMDAT (decl)) return false; if (!DECL_INLINE (decl) || (!node->local.disregard_inline_limits /* When declared inline, defer even the uninlinable functions. This allows them to be eliminated when unused. */ && !DECL_DECLARED_INLINE_P (decl) && (!node->local.inlinable || !cgraph_default_inline_p (node)))) return true; return false; } /* Debugging function for postorder and inorder code. NOTE is a string that is printed before the nodes are printed. ORDER is an array of cgraph_nodes that has COUNT useful nodes in it. */ static void print_order (const char * note, struct cgraph_node** order, int count) { int i; fprintf (cgraph_dump_file, "\n\n ordered call graph: %s\n", note); for (i = count - 1; i >= 0; i--) { struct cgraph_edge *edge; fprintf (cgraph_dump_file, "\n %s<-(", cgraph_node_name (order[i])); for (edge = order[i]->callers; edge; edge = edge->next_caller) fprintf (cgraph_dump_file, " %s", cgraph_node_name (edge->caller)); fprintf (cgraph_dump_file, ")"); } fprintf (cgraph_dump_file, "\n"); } /* FIXME -- PROFILE-RESTRUCTURE: Remove this function, it becomes a nop. */ /* Convert IN_DECL bitmap which is indexed by DECL_UID to IN_ANN, a bitmap indexed by var_ann (VAR_DECL)->uid. */ static void convert_UIDs_in_bitmap (bitmap in_ann, bitmap in_decl) { int index; bitmap_iterator bi; EXECUTE_IF_SET_IN_BITMAP(in_decl, 0, index, bi) { splay_tree_node n = splay_tree_lookup (static_vars_to_consider_by_uid, index); if (n != NULL) { tree t = (tree)n->value; var_ann_t va = var_ann (t); if (va) bitmap_set_bit(in_ann, va->uid); } } } /* FIXME -- PROFILE-RESTRUCTURE: Delete all stmts initing *_decl_uid variables. Add code to create a var_ann for tree node within the cgraph_node and have it point to the newly created static_vars_info. */ /* Create a new static_vars_info structure and place it into cgraph_node, NODE. INIT_GLOBAL causes the global part of the structure to be initialized. */ static static_vars_info_t new_static_vars_info(struct cgraph_node* node, bool init_global) { static_vars_info_t info = ggc_calloc (1, sizeof (struct static_vars_info_d)); local_static_vars_info_t l = ggc_calloc (1, sizeof (struct local_static_vars_info_d)); /* Add the info to the tree's annotation. */ var_ann_t var_ann = get_var_ann(node->decl); node->static_vars_info = info; var_ann->static_vars_info = info; info->local = l; l->statics_read_by_decl_uid = BITMAP_GGC_ALLOC (); l->statics_written_by_decl_uid = BITMAP_GGC_ALLOC (); if (init_global) { global_static_vars_info_t g = ggc_calloc (1, sizeof (struct global_static_vars_info_d)); info->global = g; g->statics_read_by_decl_uid = BITMAP_GGC_ALLOC (); g->statics_written_by_decl_uid = BITMAP_GGC_ALLOC (); g->statics_read_by_ann_uid = BITMAP_GGC_ALLOC (); g->statics_written_by_ann_uid = BITMAP_GGC_ALLOC (); g->statics_not_read_by_decl_uid = BITMAP_GGC_ALLOC (); g->statics_not_written_by_decl_uid = BITMAP_GGC_ALLOC (); g->statics_not_read_by_ann_uid = BITMAP_GGC_ALLOC (); g->statics_not_written_by_ann_uid = BITMAP_GGC_ALLOC (); } return info; } /* FIXME -- PROFILE-RESTRUCTURE: Remove this function, it becomes a nop. */ /* The bitmaps used to represent the static global variables are indexed by DECL_UID however, this is not used inside of functions to index the ssa variables. The denser var_ann (VAR_DECL)->uid is used there. This function is called from tree_dfa:find_referenced_vars after the denser representation is built. This function invalidates any cached indexes. */ void cgraph_reset_static_var_maps (void) { struct cgraph_node *node; for (node = cgraph_nodes; node; node = node->next) { static_vars_info_t info = node->static_vars_info; if (info) { global_static_vars_info_t g = info->global; if (g->var_anns_valid) { bitmap_clear (g->statics_read_by_ann_uid); bitmap_clear (g->statics_written_by_ann_uid); bitmap_clear (g->statics_not_read_by_ann_uid); bitmap_clear (g->statics_not_written_by_ann_uid); g->var_anns_valid = false; } } else /* Handle the case where a cgraph node has been inserted after the analysis. We know nothing. */ new_static_vars_info(node, true); } } /* Get the global static_vars_info structure for the function FN and make sure the ann_uid's bitmaps are properly converted. */ static global_static_vars_info_t get_global_static_vars_info (tree fn) { global_static_vars_info_t g; /* Was not compiled -O2 or higher. */ static_vars_info_t info = get_var_ann(fn)->static_vars_info; if (!info) return NULL; g = info->global; if (!g->var_anns_valid) { convert_UIDs_in_bitmap (g->statics_read_by_ann_uid, g->statics_read_by_decl_uid); convert_UIDs_in_bitmap (g->statics_written_by_ann_uid, g->statics_written_by_decl_uid); convert_UIDs_in_bitmap (g->statics_not_read_by_ann_uid, g->statics_not_read_by_decl_uid); convert_UIDs_in_bitmap (g->statics_not_written_by_ann_uid, g->statics_not_written_by_decl_uid); g->var_anns_valid = true; } return g; } /* Return a bitmap indexed by var_ann (VAR_DECL)->uid for the static variables that are not read during the execution of the function FN. Returns NULL if no data is available, such as it was not compiled with -O2 or higher. */ bitmap get_global_statics_not_read (tree fn) { global_static_vars_info_t g = get_global_static_vars_info (fn); if (g) return g->statics_not_read_by_ann_uid; else return NULL; } /* Return a bitmap indexed by var_ann (VAR_DECL)->uid for the static variables that are not written during the execution of the function FN. Note that variables written may or may not be read during the function call. Returns NULL if no data is available, such as it was not compiled with -O2 or higher. */ bitmap get_global_statics_not_written (tree fn) { global_static_vars_info_t g = get_global_static_vars_info (fn); if (g) return g->statics_not_written_by_ann_uid; else return NULL; } /* When not doing unit-at-a-time, output all functions enqueued. Return true when such a functions were found. */ bool cgraph_assemble_pending_functions (void) { bool output = false; if (flag_unit_at_a_time) return false; while (cgraph_nodes_queue) { struct cgraph_node *n = cgraph_nodes_queue; cgraph_nodes_queue = cgraph_nodes_queue->next_needed; n->next_needed = NULL; if (!n->global.inlined_to && !DECL_EXTERNAL (n->decl)) { cgraph_expand_function (n); output = true; } } return output; } /* DECL has been parsed. Take it, queue it, compile it at the whim of the logic in effect. If NESTED is true, then our caller cannot stand to have the garbage collector run at the moment. We would need to either create a new GC context, or just not compile right now. */ void cgraph_finalize_function (tree decl, bool nested) { struct cgraph_node *node = cgraph_node (decl); if (node->local.finalized) { /* As an GCC extension we allow redefinition of the function. The semantics when both copies of bodies differ is not well defined. We replace the old body with new body so in unit at a time mode we always use new body, while in normal mode we may end up with old body inlined into some functions and new body expanded and inlined in others. ??? It may make more sense to use one body for inlining and other body for expanding the function but this is difficult to do. */ /* If node->output is set, then this is a unit-at-a-time compilation and we have already begun whole-unit analysis. This is *not* testing for whether we've already emitted the function. That case can be sort-of legitimately seen with real function redefinition errors. I would argue that the front end should never present us with such a case, but don't enforce that for now. */ gcc_assert (!node->output); /* Reset our data structures so we can analyze the function again. */ memset (&node->local, 0, sizeof (node->local)); memset (&node->global, 0, sizeof (node->global)); memset (&node->rtl, 0, sizeof (node->rtl)); node->analyzed = false; node->local.redefined_extern_inline = true; while (node->callees) cgraph_remove_edge (node->callees); /* We may need to re-queue the node for assembling in case we already proceeded it and ignored as not needed. */ if (node->reachable && !flag_unit_at_a_time) { struct cgraph_node *n; for (n = cgraph_nodes_queue; n; n = n->next_needed) if (n == node) break; if (!n) node->reachable = 0; } } notice_global_symbol (decl); node->decl = decl; node->local.finalized = true; if (node->nested) lower_nested_functions (decl); gcc_assert (!node->nested); /* If not unit at a time, then we need to create the call graph now, so that called functions can be queued and emitted now. */ if (!flag_unit_at_a_time) { cgraph_analyze_function (node); cgraph_decide_inlining_incrementally (node); } if (decide_is_function_needed (node, decl)) cgraph_mark_needed_node (node); /* If not unit at a time, go ahead and emit everything we've found to be reachable at this time. */ if (!nested) { if (!cgraph_assemble_pending_functions ()) ggc_collect (); } /* If we've not yet emitted decl, tell the debug info about it. */ if (!TREE_ASM_WRITTEN (decl)) (*debug_hooks->deferred_inline_function) (decl); /* Possibly warn about unused parameters. */ if (warn_unused_parameter) do_warn_unused_parameter (decl); } /* Walk tree and record all calls. Called via walk_tree. */ static tree record_call_1 (tree *tp, int *walk_subtrees, void *data) { tree t = *tp; switch (TREE_CODE (t)) { case VAR_DECL: /* ??? Really, we should mark this decl as *potentially* referenced by this function and re-examine whether the decl is actually used after rtl has been generated. */ if (TREE_STATIC (t)) { cgraph_varpool_mark_needed_node (cgraph_varpool_node (t)); if (lang_hooks.callgraph.analyze_expr) return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees, data); } break; case ADDR_EXPR: if (flag_unit_at_a_time) { /* Record dereferences to the functions. This makes the functions reachable unconditionally. */ tree decl = TREE_OPERAND (*tp, 0); if (TREE_CODE (decl) == FUNCTION_DECL) cgraph_mark_needed_node (cgraph_node (decl)); } break; case CALL_EXPR: { tree decl = get_callee_fndecl (*tp); if (decl && TREE_CODE (decl) == FUNCTION_DECL) { cgraph_create_edge (data, cgraph_node (decl), *tp); /* When we see a function call, we don't want to look at the function reference in the ADDR_EXPR that is hanging from the CALL_EXPR we're examining here, because we would conclude incorrectly that the function's address could be taken by something that is not a function call. So only walk the function parameter list, skip the other subtrees. */ walk_tree (&TREE_OPERAND (*tp, 1), record_call_1, data, visited_nodes); *walk_subtrees = 0; } break; } default: /* Save some cycles by not walking types and declaration as we won't find anything useful there anyway. */ if (IS_TYPE_OR_DECL_P (*tp)) { *walk_subtrees = 0; break; } if ((unsigned int) TREE_CODE (t) >= LAST_AND_UNUSED_TREE_CODE) return lang_hooks.callgraph.analyze_expr (tp, walk_subtrees, data); break; } return NULL; } /* Create cgraph edges for function calls inside BODY from NODE. */ void cgraph_create_edges (struct cgraph_node *node, tree body) { /* The nodes we're interested in are never shared, so walk the tree ignoring duplicates. */ visited_nodes = pointer_set_create (); walk_tree (&body, record_call_1, node, visited_nodes); pointer_set_destroy (visited_nodes); visited_nodes = NULL; } static bool error_found; /* Callbrack of verify_cgraph_node. Check that all call_exprs have cgraph nodes. */ static tree verify_cgraph_node_1 (tree *tp, int *walk_subtrees, void *data) { tree t = *tp; tree decl; if (TREE_CODE (t) == CALL_EXPR && (decl = get_callee_fndecl (t))) { struct cgraph_edge *e = cgraph_edge (data, t); if (e) { if (e->aux) { error ("Shared call_expr:"); debug_tree (t); error_found = true; } if (e->callee->decl != cgraph_node (decl)->decl) { error ("Edge points to wrong declaration:"); debug_tree (e->callee->decl); fprintf (stderr," Instead of:"); debug_tree (decl); } e->aux = (void *)1; } else { error ("Missing callgraph edge for call expr:"); debug_tree (t); error_found = true; } } /* Save some cycles by not walking types and declaration as we won't find anything useful there anyway. */ if (IS_TYPE_OR_DECL_P (*tp)) *walk_subtrees = 0; return NULL_TREE; } /* Verify cgraph nodes of given cgraph node. */ void verify_cgraph_node (struct cgraph_node *node) { struct cgraph_edge *e; struct cgraph_node *main_clone; timevar_push (TV_CGRAPH_VERIFY); error_found = false; for (e = node->callees; e; e = e->next_callee) if (e->aux) { error ("Aux field set for edge %s->%s", cgraph_node_name (e->caller), cgraph_node_name (e->callee)); error_found = true; } for (e = node->callers; e; e = e->next_caller) { if (!e->inline_failed) { if (node->global.inlined_to != (e->caller->global.inlined_to ? e->caller->global.inlined_to : e->caller)) { error ("Inlined_to pointer is wrong"); error_found = true; } if (node->callers->next_caller) { error ("Multiple inline callers"); error_found = true; } } else if (node->global.inlined_to) { error ("Inlined_to pointer set for noninline callers"); error_found = true; } } if (!node->callers && node->global.inlined_to) { error ("Inlined_to pointer is set but no predecesors found"); error_found = true; } if (node->global.inlined_to == node) { error ("Inlined_to pointer reffers to itself"); error_found = true; } for (main_clone = cgraph_node (node->decl); main_clone; main_clone = main_clone->next_clone) if (main_clone == node) break; if (!node) { error ("Node not found in DECL_ASSEMBLER_NAME hash"); error_found = true; } if (node->analyzed && DECL_SAVED_TREE (node->decl) && !TREE_ASM_WRITTEN (node->decl) && (!DECL_EXTERNAL (node->decl) || node->global.inlined_to)) { walk_tree_without_duplicates (&DECL_SAVED_TREE (node->decl), verify_cgraph_node_1, node); for (e = node->callees; e; e = e->next_callee) { if (!e->aux) { error ("Edge %s->%s has no corresponding call_expr", cgraph_node_name (e->caller), cgraph_node_name (e->callee)); error_found = true; } e->aux = 0; } } if (error_found) { dump_cgraph_node (stderr, node); internal_error ("verify_cgraph_node failed."); } timevar_pop (TV_CGRAPH_VERIFY); } /* Verify whole cgraph structure. */ void verify_cgraph (void) { struct cgraph_node *node; if (sorrycount || errorcount) return; for (node = cgraph_nodes; node; node = node->next) verify_cgraph_node (node); } /* Analyze the function scheduled to be output. */ static void cgraph_analyze_function (struct cgraph_node *node) { tree decl = node->decl; struct cgraph_edge *e; current_function_decl = decl; /* First kill forward declaration so reverse inlining works properly. */ cgraph_create_edges (node, DECL_SAVED_TREE (decl)); node->local.inlinable = tree_inlinable_function_p (decl); node->local.self_insns = estimate_num_insns (DECL_SAVED_TREE (decl)); if (node->local.inlinable) node->local.disregard_inline_limits = lang_hooks.tree_inlining.disregard_inline_limits (decl); for (e = node->callers; e; e = e->next_caller) { if (node->local.redefined_extern_inline) e->inline_failed = N_("redefined extern inline functions are not " "considered for inlining"); else if (!node->local.inlinable) e->inline_failed = N_("function not inlinable"); else e->inline_failed = N_("function not considered for inlining"); } if (flag_really_no_inline && !node->local.disregard_inline_limits) node->local.inlinable = 0; /* Inlining characteristics are maintained by the cgraph_mark_inline. */ node->global.insns = node->local.self_insns; node->analyzed = true; current_function_decl = NULL; } /* Analyze the whole compilation unit once it is parsed completely. */ void cgraph_finalize_compilation_unit (void) { struct cgraph_node *node; if (!flag_unit_at_a_time) { cgraph_assemble_pending_functions (); return; } cgraph_varpool_assemble_pending_decls (); if (!quiet_flag) fprintf (stderr, "\nAnalyzing compilation unit\n"); timevar_push (TV_CGRAPH); if (cgraph_dump_file) { fprintf (cgraph_dump_file, "Initial entry points:"); for (node = cgraph_nodes; node; node = node->next) if (node->needed && DECL_SAVED_TREE (node->decl)) fprintf (cgraph_dump_file, " %s", cgraph_node_name (node)); fprintf (cgraph_dump_file, "\n"); } /* Propagate reachability flag and lower representation of all reachable functions. In the future, lowering will introduce new functions and new entry points on the way (by template instantiation and virtual method table generation for instance). */ while (cgraph_nodes_queue) { struct cgraph_edge *edge; tree decl = cgraph_nodes_queue->decl; node = cgraph_nodes_queue; cgraph_nodes_queue = cgraph_nodes_queue->next_needed; node->next_needed = NULL; /* ??? It is possible to create extern inline function and later using weak alas attribute to kill its body. See gcc.c-torture/compile/20011119-1.c */ if (!DECL_SAVED_TREE (decl)) continue; gcc_assert (!node->analyzed && node->reachable); gcc_assert (DECL_SAVED_TREE (decl)); cgraph_analyze_function (node); for (edge = node->callees; edge; edge = edge->next_callee) if (!edge->callee->reachable) cgraph_mark_reachable_node (edge->callee); cgraph_varpool_assemble_pending_decls (); } /* Collect entry points to the unit. */ if (cgraph_dump_file) { fprintf (cgraph_dump_file, "Unit entry points:"); for (node = cgraph_nodes; node; node = node->next) if (node->needed && DECL_SAVED_TREE (node->decl)) fprintf (cgraph_dump_file, " %s", cgraph_node_name (node)); fprintf (cgraph_dump_file, "\n\nInitial "); dump_cgraph (cgraph_dump_file); } if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nReclaiming functions:"); for (node = cgraph_nodes; node; node = node->next) { tree decl = node->decl; if (!node->reachable && DECL_SAVED_TREE (decl)) { if (cgraph_dump_file) fprintf (cgraph_dump_file, " %s", cgraph_node_name (node)); cgraph_remove_node (node); } else node->next_needed = NULL; } if (cgraph_dump_file) { fprintf (cgraph_dump_file, "\n\nReclaimed "); dump_cgraph (cgraph_dump_file); } ggc_collect (); timevar_pop (TV_CGRAPH); } /* Figure out what functions we want to assemble. */ static void cgraph_mark_functions_to_output (void) { struct cgraph_node *node; for (node = cgraph_nodes; node; node = node->next) { tree decl = node->decl; struct cgraph_edge *e; gcc_assert (!node->output); for (e = node->callers; e; e = e->next_caller) if (e->inline_failed) break; /* We need to output all local functions that are used and not always inlined, as well as those that are reachable from outside the current compilation unit. */ if (DECL_SAVED_TREE (decl) && !node->global.inlined_to && (node->needed || (e && node->reachable)) && !TREE_ASM_WRITTEN (decl) && !DECL_EXTERNAL (decl)) node->output = 1; else { /* We should've reclaimed all functions that are not needed. */ #ifdef ENABLE_CHECKING if (!node->global.inlined_to && DECL_SAVED_TREE (decl) && !DECL_EXTERNAL (decl)) { dump_cgraph_node (stderr, node); internal_error ("failed to reclaim unneeded function"); } #endif gcc_assert (node->global.inlined_to || !DECL_SAVED_TREE (decl) || DECL_EXTERNAL (decl)); } } } /* Expand function specified by NODE. */ static void cgraph_expand_function (struct cgraph_node *node) { tree decl = node->decl; /* We ought to not compile any inline clones. */ gcc_assert (!node->global.inlined_to); if (flag_unit_at_a_time) announce_function (decl); /* Generate RTL for the body of DECL. */ lang_hooks.callgraph.expand_function (decl); /* Make sure that BE didn't give up on compiling. */ /* ??? Can happen with nested function of extern inline. */ gcc_assert (TREE_ASM_WRITTEN (node->decl)); current_function_decl = NULL; if (!cgraph_preserve_function_body_p (node->decl)) { DECL_SAVED_TREE (node->decl) = NULL; DECL_STRUCT_FUNCTION (node->decl) = NULL; DECL_INITIAL (node->decl) = error_mark_node; /* Eliminate all call edges. This is important so the call_expr no longer points to the dead function body. */ while (node->callees) cgraph_remove_edge (node->callees); } } /* Fill array order with all nodes with output flag set in the reverse topological order. */ static int cgraph_postorder (struct cgraph_node **order) { struct cgraph_node *node, *node2; int stack_size = 0; int order_pos = 0; struct cgraph_edge *edge, last; struct cgraph_node **stack = xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *)); /* We have to deal with cycles nicely, so use a depth first traversal output algorithm. Ignore the fact that some functions won't need to be output and put them into order as well, so we get dependencies right through intline functions. */ for (node = cgraph_nodes; node; node = node->next) node->aux = NULL; for (node = cgraph_nodes; node; node = node->next) if (!node->aux) { node2 = node; if (!node->callers) node->aux = &last; else node->aux = node->callers; while (node2) { while (node2->aux != &last) { edge = node2->aux; if (edge->next_caller) node2->aux = edge->next_caller; else node2->aux = &last; if (!edge->caller->aux) { if (!edge->caller->callers) edge->caller->aux = &last; else edge->caller->aux = edge->caller->callers; stack[stack_size++] = node2; node2 = edge->caller; break; } } if (node2->aux == &last) { order[order_pos++] = node2; if (stack_size) node2 = stack[--stack_size]; else node2 = NULL; } } } free (stack); return order_pos; } struct searchc_env { struct cgraph_node **stack; int stack_size; struct cgraph_node **result; int order_pos; splay_tree nodes_marked_new; bool reduce; int count; }; struct dfs_info { int dfn_number; int low_link; bool new; bool on_stack; }; /* This is an implementation of Tarjan's strongly connected region finder as reprinted in Aho Hopcraft and Ullman's The Design and Analysis of Computer Programs (1975) pages 192-193. This version has been customized for cgraph_nodes. The env parameter is because it is recursive and there are no nested functions here. This function should only be called from itself or cgraph_reduced_inorder. ENV is a stack env and would be unnecessary if C had nested functions. V is the node to start searching from. */ static void searchc (struct searchc_env* env, struct cgraph_node *v) { struct cgraph_edge *edge; struct dfs_info *v_info = v->aux; /* mark node as old */ v_info->new = false; splay_tree_remove (env->nodes_marked_new, v->uid); v_info->dfn_number = env->count; v_info->low_link = env->count; env->count++; env->stack[(env->stack_size)++] = v; v_info->on_stack = true; for (edge = v->callers; edge; edge = edge->next_caller) { struct dfs_info * w_info; struct cgraph_node *w = edge->caller; /* skip the nodes that we are supposed to ignore */ if (w->aux) { w_info = w->aux; if (w_info->new) { searchc (env, w); v_info->low_link = (v_info->low_link < w_info->low_link) ? v_info->low_link : w_info->low_link; } else if ((w_info->dfn_number < v_info->dfn_number) && (w_info->on_stack)) v_info->low_link = (w_info->dfn_number < v_info->low_link) ? w_info->dfn_number : v_info->low_link; } } if (v_info->low_link == v_info->dfn_number) { struct cgraph_node *last = NULL; struct cgraph_node *x; struct dfs_info *x_info; do { x = env->stack[--(env->stack_size)]; x_info = x->aux; x_info->on_stack = false; if (env->reduce) { x->next_cycle = last; last = x; } else env->result[env->order_pos++] = x; } while (v != x); if (env->reduce) env->result[env->order_pos++] = v; } } /* Topsort the call graph by caller relation. Put the result in ORDER. The REDUCE flag is true if you want the cycles reduced to single nodes. Only consider nodes that have the output bit set. */ static int cgraph_reduced_inorder (struct cgraph_node **order, bool reduce) { struct cgraph_node *node; struct searchc_env env; splay_tree_node result; env.stack = xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *)); env.stack_size = 0; env.result = order; env.order_pos = 0; env.nodes_marked_new = splay_tree_new (splay_tree_compare_ints, 0, 0); env.count = 1; env.reduce = reduce; for (node = cgraph_nodes; node; node = node->next) if (node->output) { struct dfs_info *info = xcalloc (1, sizeof (struct dfs_info)); info->new = true; info->on_stack = false; node->aux = info; node->next_cycle = NULL; splay_tree_insert (env.nodes_marked_new, node->uid, (splay_tree_value)node); } else node->aux = NULL; result = splay_tree_min (env.nodes_marked_new); while (result) { node = (struct cgraph_node *)result->value; searchc (&env, node); result = splay_tree_min (env.nodes_marked_new); } splay_tree_delete (env.nodes_marked_new); free (env.stack); for (node = cgraph_nodes; node; node = node->next) if (node->aux) { free (node->aux); node->aux = NULL; } return env.order_pos; } /* Perform reachability analysis and reclaim all unreachable nodes. This function also remove unneeded bodies of extern inline functions and thus needs to be done only after inlining decisions has been made. */ static bool cgraph_remove_unreachable_nodes (void) { struct cgraph_node *first = (void *) 1; struct cgraph_node *node; bool changed = false; int insns = 0; #ifdef ENABLE_CHECKING verify_cgraph (); #endif if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nReclaiming functions:"); #ifdef ENABLE_CHECKING for (node = cgraph_nodes; node; node = node->next) gcc_assert (!node->aux); #endif for (node = cgraph_nodes; node; node = node->next) if (node->needed && !node->global.inlined_to && (!DECL_EXTERNAL (node->decl) || !node->analyzed)) { node->aux = first; first = node; } else gcc_assert (!node->aux); /* Perform reachability analysis. As a special case do not consider extern inline functions not inlined as live because we won't output them at all. */ while (first != (void *) 1) { struct cgraph_edge *e; node = first; first = first->aux; for (e = node->callees; e; e = e->next_callee) if (!e->callee->aux && node->analyzed && (!e->inline_failed || !e->callee->analyzed || !DECL_EXTERNAL (e->callee->decl))) { e->callee->aux = first; first = e->callee; } } /* Remove unreachable nodes. Extern inline functions need special care; Unreachable extern inline functions shall be removed. Reachable extern inline functions we never inlined shall get their bodies eliminated. Reachable extern inline functions we sometimes inlined will be turned into unanalyzed nodes so they look like for true extern functions to the rest of code. Body of such functions is released via remove_node once the inline clones are eliminated. */ for (node = cgraph_nodes; node; node = node->next) { if (!node->aux) { int local_insns; tree decl = node->decl; node->global.inlined_to = NULL; if (DECL_STRUCT_FUNCTION (decl)) local_insns = node->local.self_insns; else local_insns = 0; if (cgraph_dump_file) fprintf (cgraph_dump_file, " %s", cgraph_node_name (node)); if (!node->analyzed || !DECL_EXTERNAL (node->decl)) cgraph_remove_node (node); else { struct cgraph_edge *e; for (e = node->callers; e; e = e->next_caller) if (e->caller->aux) break; if (e || node->needed) { struct cgraph_node *clone; for (clone = node->next_clone; clone; clone = clone->next_clone) if (clone->aux) break; if (!clone) { DECL_SAVED_TREE (node->decl) = NULL; DECL_STRUCT_FUNCTION (node->decl) = NULL; DECL_INITIAL (node->decl) = error_mark_node; } while (node->callees) cgraph_remove_edge (node->callees); node->analyzed = false; } else cgraph_remove_node (node); } if (!DECL_SAVED_TREE (decl)) insns += local_insns; changed = true; } } for (node = cgraph_nodes; node; node = node->next) node->aux = NULL; if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nReclaimed %i insns", insns); return changed; } /* Estimate size of the function after inlining WHAT into TO. */ static int cgraph_estimate_size_after_inlining (int times, struct cgraph_node *to, struct cgraph_node *what) { return (what->global.insns - INSNS_PER_CALL) * times + to->global.insns; } /* Estimate the growth caused by inlining NODE into all callees. */ static int cgraph_estimate_growth (struct cgraph_node *node) { int growth = 0; struct cgraph_edge *e; for (e = node->callers; e; e = e->next_caller) if (e->inline_failed) growth += (cgraph_estimate_size_after_inlining (1, e->caller, node) - e->caller->global.insns); /* ??? Wrong for self recursive functions or cases where we decide to not inline for different reasons, but it is not big deal as in that case we will keep the body around, but we will also avoid some inlining. */ if (!node->needed && !DECL_EXTERNAL (node->decl)) growth -= node->global.insns; return growth; } /* E is expected to be an edge being inlined. Clone destination node of the edge and redirect it to the new clone. DUPLICATE is used for bookkeeping on whether we are actually creating new clones or re-using node originally representing out-of-line function call. */ void cgraph_clone_inlined_nodes (struct cgraph_edge *e, bool duplicate) { struct cgraph_node *n; /* We may eliminate the need for out-of-line copy to be output. In that case just go ahead and re-use it. */ if (!e->callee->callers->next_caller && (!e->callee->needed || DECL_EXTERNAL (e->callee->decl)) && duplicate && flag_unit_at_a_time) { gcc_assert (!e->callee->global.inlined_to); if (!DECL_EXTERNAL (e->callee->decl)) overall_insns -= e->callee->global.insns, nfunctions_inlined++; duplicate = 0; } else if (duplicate) { n = cgraph_clone_node (e->callee); cgraph_redirect_edge_callee (e, n); } if (e->caller->global.inlined_to) e->callee->global.inlined_to = e->caller->global.inlined_to; else e->callee->global.inlined_to = e->caller; /* Recursively clone all bodies. */ for (e = e->callee->callees; e; e = e->next_callee) if (!e->inline_failed) cgraph_clone_inlined_nodes (e, duplicate); } /* Mark edge E as inlined and update callgraph accordingly. */ void cgraph_mark_inline_edge (struct cgraph_edge *e) { int old_insns = 0, new_insns = 0; struct cgraph_node *to = NULL, *what; gcc_assert (e->inline_failed); e->inline_failed = NULL; if (!e->callee->global.inlined && flag_unit_at_a_time) DECL_POSSIBLY_INLINED (e->callee->decl) = true; e->callee->global.inlined = true; cgraph_clone_inlined_nodes (e, true); what = e->callee; /* Now update size of caller and all functions caller is inlined into. */ for (;e && !e->inline_failed; e = e->caller->callers) { old_insns = e->caller->global.insns; new_insns = cgraph_estimate_size_after_inlining (1, e->caller, what); gcc_assert (new_insns >= 0); to = e->caller; to->global.insns = new_insns; } gcc_assert (what->global.inlined_to == to); overall_insns += new_insns - old_insns; ncalls_inlined++; } /* Mark all calls of EDGE->CALLEE inlined into EDGE->CALLER. Return following unredirected edge in the list of callers of EDGE->CALLEE */ static struct cgraph_edge * cgraph_mark_inline (struct cgraph_edge *edge) { struct cgraph_node *to = edge->caller; struct cgraph_node *what = edge->callee; struct cgraph_edge *e, *next; int times = 0; /* Look for all calls, mark them inline and clone recursively all inlined functions. */ for (e = what->callers; e; e = next) { next = e->next_caller; if (e->caller == to && e->inline_failed) { cgraph_mark_inline_edge (e); if (e == edge) edge = next; times++; } } gcc_assert (times); return edge; } /* Return false when inlining WHAT into TO is not good idea as it would cause too large growth of function bodies. */ static bool cgraph_check_inline_limits (struct cgraph_node *to, struct cgraph_node *what, const char **reason) { int times = 0; struct cgraph_edge *e; int newsize; int limit; if (to->global.inlined_to) to = to->global.inlined_to; for (e = to->callees; e; e = e->next_callee) if (e->callee == what) times++; /* When inlining large function body called once into small function, take the inlined function as base for limiting the growth. */ if (to->local.self_insns > what->local.self_insns) limit = to->local.self_insns; else limit = what->local.self_insns; limit += limit * PARAM_VALUE (PARAM_LARGE_FUNCTION_GROWTH) / 100; newsize = cgraph_estimate_size_after_inlining (times, to, what); if (newsize > PARAM_VALUE (PARAM_LARGE_FUNCTION_INSNS) && newsize > limit) { if (reason) *reason = N_("--param large-function-growth limit reached"); return false; } return true; } /* Return true when function N is small enough to be inlined. */ static bool cgraph_default_inline_p (struct cgraph_node *n) { if (!DECL_INLINE (n->decl) || !DECL_SAVED_TREE (n->decl)) return false; if (DECL_DECLARED_INLINE_P (n->decl)) return n->global.insns < MAX_INLINE_INSNS_SINGLE; else return n->global.insns < MAX_INLINE_INSNS_AUTO; } /* Return true when inlining WHAT would create recursive inlining. We call recursive inlining all cases where same function appears more than once in the single recursion nest path in the inline graph. */ static bool cgraph_recursive_inlining_p (struct cgraph_node *to, struct cgraph_node *what, const char **reason) { bool recursive; if (to->global.inlined_to) recursive = what->decl == to->global.inlined_to->decl; else recursive = what->decl == to->decl; /* Marking recursive function inline has sane semantic and thus we should not warn on it. */ if (recursive && reason) *reason = (what->local.disregard_inline_limits ? N_("recursive inlining") : ""); return recursive; } /* Recompute heap nodes for each of callees. */ static void update_callee_keys (fibheap_t heap, struct fibnode **heap_node, struct cgraph_node *node) { struct cgraph_edge *e; for (e = node->callees; e; e = e->next_callee) if (e->inline_failed && heap_node[e->callee->uid]) fibheap_replace_key (heap, heap_node[e->callee->uid], cgraph_estimate_growth (e->callee)); else if (!e->inline_failed) update_callee_keys (heap, heap_node, e->callee); } /* Enqueue all recursive calls from NODE into queue linked via aux pointers in between FIRST and LAST. WHERE is used for bookkeeping while looking int calls inlined within NODE. */ static void lookup_recursive_calls (struct cgraph_node *node, struct cgraph_node *where, struct cgraph_edge **first, struct cgraph_edge **last) { struct cgraph_edge *e; for (e = where->callees; e; e = e->next_callee) if (e->callee == node) { if (!*first) *first = e; else (*last)->aux = e; *last = e; } for (e = where->callees; e; e = e->next_callee) if (!e->inline_failed) lookup_recursive_calls (node, e->callee, first, last); } /* Decide on recursive inlining: in the case function has recursive calls, inline until body size reaches given argument. */ static void cgraph_decide_recursive_inlining (struct cgraph_node *node) { int limit = PARAM_VALUE (PARAM_MAX_INLINE_INSNS_RECURSIVE_AUTO); int max_depth = PARAM_VALUE (PARAM_MAX_INLINE_RECURSIVE_DEPTH_AUTO); struct cgraph_edge *first_call = NULL, *last_call = NULL; struct cgraph_edge *last_in_current_depth; struct cgraph_edge *e; struct cgraph_node *master_clone; int depth = 0; int n = 0; if (DECL_DECLARED_INLINE_P (node->decl)) { limit = PARAM_VALUE (PARAM_MAX_INLINE_INSNS_RECURSIVE); max_depth = PARAM_VALUE (PARAM_MAX_INLINE_RECURSIVE_DEPTH); } /* Make sure that function is small enough to be considered for inlining. */ if (!max_depth || cgraph_estimate_size_after_inlining (1, node, node) >= limit) return; lookup_recursive_calls (node, node, &first_call, &last_call); if (!first_call) return; if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nPerforming recursive inlining on %s\n", cgraph_node_name (node)); /* We need original clone to copy around. */ master_clone = cgraph_clone_node (node); master_clone->needed = true; for (e = master_clone->callees; e; e = e->next_callee) if (!e->inline_failed) cgraph_clone_inlined_nodes (e, true); /* Do the inlining and update list of recursive call during process. */ last_in_current_depth = last_call; while (first_call && cgraph_estimate_size_after_inlining (1, node, master_clone) <= limit) { struct cgraph_edge *curr = first_call; first_call = first_call->aux; curr->aux = NULL; cgraph_redirect_edge_callee (curr, master_clone); cgraph_mark_inline_edge (curr); lookup_recursive_calls (node, curr->callee, &first_call, &last_call); if (last_in_current_depth && ++depth >= max_depth) break; n++; } /* Cleanup queue pointers. */ while (first_call) { struct cgraph_edge *next = first_call->aux; first_call->aux = NULL; first_call = next; } if (cgraph_dump_file) fprintf (cgraph_dump_file, "\n Inlined %i times, body grown from %i to %i insns\n", n, master_clone->global.insns, node->global.insns); /* Remove master clone we used for inlining. We rely that clones inlined into master clone gets queued just before master clone so we don't need recursion. */ for (node = cgraph_nodes; node != master_clone; node = node->next) if (node->global.inlined_to == master_clone) cgraph_remove_node (node); cgraph_remove_node (master_clone); } /* Set inline_failed for all callers of given function to REASON. */ static void cgraph_set_inline_failed (struct cgraph_node *node, const char *reason) { struct cgraph_edge *e; if (cgraph_dump_file) fprintf (cgraph_dump_file, "Inlining failed: %s\n", reason); for (e = node->callers; e; e = e->next_caller) if (e->inline_failed) e->inline_failed = reason; } /* We use greedy algorithm for inlining of small functions: All inline candidates are put into prioritized heap based on estimated growth of the overall number of instructions and then update the estimates. INLINED and INLINED_CALEES are just pointers to arrays large enough to be passed to cgraph_inlined_into and cgraph_inlined_callees. */ static void cgraph_decide_inlining_of_small_functions (void) { struct cgraph_node *node; fibheap_t heap = fibheap_new (); struct fibnode **heap_node = xcalloc (cgraph_max_uid, sizeof (struct fibnode *)); int max_insns = ((HOST_WIDEST_INT) initial_insns * (100 + PARAM_VALUE (PARAM_INLINE_UNIT_GROWTH)) / 100); /* Put all inline candidates into the heap. */ for (node = cgraph_nodes; node; node = node->next) { if (!node->local.inlinable || !node->callers || node->local.disregard_inline_limits) continue; if (!cgraph_default_inline_p (node)) { cgraph_set_inline_failed (node, N_("--param max-inline-insns-single limit reached")); continue; } heap_node[node->uid] = fibheap_insert (heap, cgraph_estimate_growth (node), node); } if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nDeciding on smaller functions:\n"); while (overall_insns <= max_insns && (node = fibheap_extract_min (heap))) { struct cgraph_edge *e, *next; int old_insns = overall_insns; heap_node[node->uid] = NULL; if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nConsidering %s with %i insns\n" " Estimated growth is %+i insns.\n", cgraph_node_name (node), node->global.insns, cgraph_estimate_growth (node)); if (!cgraph_default_inline_p (node)) { cgraph_set_inline_failed (node, N_("--param max-inline-insns-single limit reached after inlining into the callee")); continue; } for (e = node->callers; e; e = next) { next = e->next_caller; if (e->inline_failed) { struct cgraph_node *where; if (cgraph_recursive_inlining_p (e->caller, e->callee, &e->inline_failed) || !cgraph_check_inline_limits (e->caller, e->callee, &e->inline_failed)) { if (cgraph_dump_file) fprintf (cgraph_dump_file, " Not inlining into %s:%s.\n", cgraph_node_name (e->caller), e->inline_failed); continue; } next = cgraph_mark_inline (e); where = e->caller; if (where->global.inlined_to) where = where->global.inlined_to; if (heap_node[where->uid]) fibheap_replace_key (heap, heap_node[where->uid], cgraph_estimate_growth (where)); if (cgraph_dump_file) fprintf (cgraph_dump_file, " Inlined into %s which now has %i insns.\n", cgraph_node_name (e->caller), e->caller->global.insns); } } cgraph_decide_recursive_inlining (node); /* Similarly all functions called by the function we just inlined are now called more times; update keys. */ update_callee_keys (heap, heap_node, node); if (cgraph_dump_file) fprintf (cgraph_dump_file, " Inlined for a net change of %+i insns.\n", overall_insns - old_insns); } while ((node = fibheap_extract_min (heap)) != NULL) if (!node->local.disregard_inline_limits) cgraph_set_inline_failed (node, N_("--param inline-unit-growth limit reached")); fibheap_delete (heap); free (heap_node); } /* Decide on the inlining. We do so in the topological order to avoid expenses on updating data structures. */ static void cgraph_decide_inlining (void) { struct cgraph_node *node; int nnodes; struct cgraph_node **order = xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *)); int old_insns = 0; int i; for (node = cgraph_nodes; node; node = node->next) initial_insns += node->local.self_insns; overall_insns = initial_insns; nnodes = cgraph_postorder (order); if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nDeciding on inlining. Starting with %i insns.\n", initial_insns); for (node = cgraph_nodes; node; node = node->next) node->aux = 0; if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nInlining always_inline functions:\n"); /* In the first pass mark all always_inline edges. Do this with a priority so none of our later choices will make this impossible. */ for (i = nnodes - 1; i >= 0; i--) { struct cgraph_edge *e, *next; node = order[i]; if (!node->local.disregard_inline_limits) continue; if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nConsidering %s %i insns (always inline)\n", cgraph_node_name (node), node->global.insns); old_insns = overall_insns; for (e = node->callers; e; e = next) { next = e->next_caller; if (!e->inline_failed) continue; if (cgraph_recursive_inlining_p (e->caller, e->callee, &e->inline_failed)) continue; cgraph_mark_inline_edge (e); if (cgraph_dump_file) fprintf (cgraph_dump_file, " Inlined into %s which now has %i insns.\n", cgraph_node_name (e->caller), e->caller->global.insns); } if (cgraph_dump_file) fprintf (cgraph_dump_file, " Inlined for a net change of %+i insns.\n", overall_insns - old_insns); } if (!flag_really_no_inline) { cgraph_decide_inlining_of_small_functions (); if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nDeciding on functions called once:\n"); /* And finally decide what functions are called once. */ for (i = nnodes - 1; i >= 0; i--) { node = order[i]; if (node->callers && !node->callers->next_caller && !node->needed && node->local.inlinable && node->callers->inline_failed && !DECL_EXTERNAL (node->decl) && !DECL_COMDAT (node->decl)) { bool ok = true; struct cgraph_node *node1; /* Verify that we won't duplicate the caller. */ for (node1 = node->callers->caller; node1->callers && !node1->callers->inline_failed && ok; node1 = node1->callers->caller) if (node1->callers->next_caller || node1->needed) ok = false; if (ok) { if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nConsidering %s %i insns.\n" " Called once from %s %i insns.\n", cgraph_node_name (node), node->global.insns, cgraph_node_name (node->callers->caller), node->callers->caller->global.insns); old_insns = overall_insns; if (cgraph_check_inline_limits (node->callers->caller, node, NULL)) { cgraph_mark_inline (node->callers); if (cgraph_dump_file) fprintf (cgraph_dump_file, " Inlined into %s which now has %i insns" " for a net change of %+i insns.\n", cgraph_node_name (node->callers->caller), node->callers->caller->global.insns, overall_insns - old_insns); } else { if (cgraph_dump_file) fprintf (cgraph_dump_file, " Inline limit reached, not inlined.\n"); } } } } } /* We will never output extern functions we didn't inline. ??? Perhaps we can prevent accounting of growth of external inline functions. */ cgraph_remove_unreachable_nodes (); if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nInlined %i calls, eliminated %i functions, " "%i insns turned to %i insns.\n\n", ncalls_inlined, nfunctions_inlined, initial_insns, overall_insns); free (order); } /* Decide on the inlining. We do so in the topological order to avoid expenses on updating data structures. */ static void cgraph_decide_inlining_incrementally (struct cgraph_node *node) { struct cgraph_edge *e; /* First of all look for always inline functions. */ for (e = node->callees; e; e = e->next_callee) if (e->callee->local.disregard_inline_limits && e->inline_failed && !cgraph_recursive_inlining_p (node, e->callee, &e->inline_failed) /* ??? It is possible that renaming variable removed the function body in duplicate_decls. See gcc.c-torture/compile/20011119-2.c */ && DECL_SAVED_TREE (e->callee->decl)) cgraph_mark_inline (e); /* Now do the automatic inlining. */ if (!flag_really_no_inline) for (e = node->callees; e; e = e->next_callee) if (e->callee->local.inlinable && e->inline_failed && !e->callee->local.disregard_inline_limits && !cgraph_recursive_inlining_p (node, e->callee, &e->inline_failed) && cgraph_check_inline_limits (node, e->callee, &e->inline_failed) && DECL_SAVED_TREE (e->callee->decl)) { if (cgraph_default_inline_p (e->callee)) cgraph_mark_inline (e); else e->inline_failed = N_("--param max-inline-insns-single limit reached"); } } /* Return true when CALLER_DECL should be inlined into CALLEE_DECL. */ bool cgraph_inline_p (struct cgraph_edge *e, const char **reason) { *reason = e->inline_failed; return !e->inline_failed; } /* FIXME this needs to be enhanced. If we are compiling a single module this returns true if the variable is a module level static, but if we are doing whole program compilation, this could return true if TREE_PUBLIC is true. */ /* Return true if the variable T is the right kind of static variable to perform compilation unit scope escape analysis. */ static inline bool has_proper_scope_for_analysis (tree t) { return (TREE_STATIC(t)) && !(TREE_PUBLIC(t)) && !(TREE_THIS_VOLATILE(t)); } /* Check to see if T is a read or address of operation on a static var we are interested in analyzing. FN is passed in to get access to its bit vectors. */ static void check_rhs_var (struct cgraph_node *fn, tree t) { if (TREE_CODE (t) == ADDR_EXPR) { tree x = TREE_OPERAND (t, 0); if ((TREE_CODE (x) == VAR_DECL) && has_proper_scope_for_analysis (x)) { if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nadding address:%s", lang_hooks.decl_printable_name (x, 2)); /* FIXME -- PROFILE-RESTRUCTURE: Change the call from DECL_UID to get the uid from the var_ann field. */ bitmap_set_bit (module_statics_escape, DECL_UID (x)); } } t = get_base_address (t); if (!t) return; if ((TREE_CODE (t) == VAR_DECL) && has_proper_scope_for_analysis (t)) { if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nadding rhs:%s", lang_hooks.decl_printable_name (t, 2)); /* FIXME -- PROFILE-RESTRUCTURE: Change the call from DECL_UID to get the uid from the var_ann field. */ bitmap_set_bit (fn->static_vars_info->local->statics_read_by_decl_uid, DECL_UID (t)); } } /* Check to see if T is an assignment to a static var we are interrested in analyzing. FN is passed in to get access to its bit vectors. */ static void check_lhs_var (struct cgraph_node *fn, tree t) { t = get_base_address (t); if (!t) return; if ((TREE_CODE (t) == VAR_DECL) && has_proper_scope_for_analysis (t)) { if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nadding lhs:%s", lang_hooks.decl_printable_name (t, 2)); /* FIXME -- PROFILE-RESTRUCTURE: Change the call from DECL_UID to get the uid from the var_ann field. */ bitmap_set_bit (fn->static_vars_info->local->statics_written_by_decl_uid, DECL_UID (t)); } } /* This is a scaled down version of get_asm_expr_operands from tree_ssa_operands.c. The version there runs much later and assumes that aliasing information is already available. Here we are just trying to find if the set of inputs and outputs contain references or address of operations to local static variables. FN is the function being analyzed and STMT is the actual asm statement. */ static void get_asm_expr_operands (struct cgraph_node * fn, tree stmt) { int noutputs = list_length (ASM_OUTPUTS (stmt)); const char **oconstraints = (const char **) alloca ((noutputs) * sizeof (const char *)); int i; tree link; const char *constraint; bool allows_mem, allows_reg, is_inout; for (i=0, link = ASM_OUTPUTS (stmt); link; ++i, link = TREE_CHAIN (link)) { oconstraints[i] = constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); parse_output_constraint (&constraint, i, 0, 0, &allows_mem, &allows_reg, &is_inout); /* Memory operands are addressable. Note that STMT needs the address of this operand. */ if (!allows_reg && allows_mem) { check_lhs_var (fn, TREE_VALUE (link)); } } for (link = ASM_INPUTS (stmt); link; link = TREE_CHAIN (link)) { constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (link))); parse_input_constraint (&constraint, 0, 0, noutputs, 0, oconstraints, &allows_mem, &allows_reg); /* Memory operands are addressable. Note that STMT needs the address of this operand. */ if (!allows_reg && allows_mem) { check_rhs_var (fn, TREE_VALUE (link)); } } for (link = ASM_CLOBBERS (stmt); link; link = TREE_CHAIN (link)) if (TREE_VALUE (link) == memory_identifier) { /* Abandon all hope, ye who enter here. */ local_static_vars_info_t l = fn->static_vars_info->local; bitmap_a_or_b (l->statics_read_by_decl_uid, l->statics_read_by_decl_uid, all_module_statics); bitmap_a_or_b (l->statics_written_by_decl_uid, l->statics_written_by_decl_uid, all_module_statics); } } /* Check the parameters of a function call from CALLER to CALL_EXPR to see if any of them are static vars. Also check to see if this is either an indirect call, a call outside the compilation unit, or has special attributes that effect the clobbers. The caller parameter is the tree node for the caller and the second operand is the tree node for the entire call expression. */ static void process_call_for_static_vars(struct cgraph_node * caller, tree call_expr) { int flags = call_expr_flags(call_expr); tree operandList = TREE_OPERAND (call_expr, 1); tree operand; for (operand = operandList; operand != NULL_TREE; operand = TREE_CHAIN (operand)) { tree argument = TREE_VALUE (operand); check_rhs_var (caller, argument); } /* Const and pure functions have less clobber effects than other functions so we process these first. Otherwise if it is a call outside the compilation unit or an indirect call we punt. This leaves local calls which will be processed by following the call graph. */ if (flags & ECF_CONST) return; else if (flags & ECF_PURE) caller->local.calls_write_all = true; else { tree callee_t = get_callee_fndecl (call_expr); if (callee_t == NULL) { /* Indirect call. */ caller->local.calls_read_all = true; caller->local.calls_write_all = true; } else { struct cgraph_node* callee = cgraph_node(callee_t); if (callee->local.external) { caller->local.calls_read_all = true; caller->local.calls_write_all = true; } } } } /* FIXME -- PROFILE-RESTRUCTURE: Change to walk by explicitly walking the basic blocks rather than calling walktree. */ /* Walk tree and record all calls. Called via walk_tree. FIXME When this is moved into the tree-profiling-branch, and is dealing with low GIMPLE, this routine should be changed to use tree iterators rather than being a walk_tree callback. The data is the function that is being scanned. */ /* TP is the part of the tree currently under the microscope. WALK_SUBTREES is part of the walk_tree api but is unused here. DATA is cgraph_node of the function being walked. */ static tree scan_for_static_refs (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, void *data) { struct cgraph_node *fn = data; tree t = *tp; switch (TREE_CODE (t)) { case MODIFY_EXPR: { /* First look on the lhs and see what variable is stored to */ tree rhs = TREE_OPERAND (t, 1); check_lhs_var (fn, TREE_OPERAND (t, 0)); /* Next check the operands on the rhs to see if they are ok. */ switch (TREE_CODE_CLASS (TREE_CODE (rhs))) { case tcc_binary: check_rhs_var (fn, TREE_OPERAND (rhs, 0)); check_rhs_var (fn, TREE_OPERAND (rhs, 1)); break; case tcc_unary: case tcc_reference: check_rhs_var (fn, TREE_OPERAND (rhs, 0)); break; case tcc_declaration: check_rhs_var (fn, rhs); break; case tcc_expression: switch (TREE_CODE (rhs)) { case ADDR_EXPR: check_rhs_var (fn, rhs); break; case CALL_EXPR: process_call_for_static_vars (fn, rhs); break; default: break; } break; default: break; } } break; case CALL_EXPR: process_call_for_static_vars (fn, t); break; case ASM_EXPR: get_asm_expr_operands (fn, t); break; default: break; } return NULL; } /* This is the main routine for finding the reference patterns for global variables within a function FN */ static void cgraph_characterize_statics_local (struct cgraph_node *fn) { tree decl = fn->decl; static_vars_info_t info = new_static_vars_info(fn, false); local_static_vars_info_t l = info->local; /* The nodes we're interested in are never shared, so walk the tree ignoring duplicates. */ visited_nodes = pointer_set_create (); /* FIXME -- PROFILE-RESTRUCTURE: Remove creation of _decl_uid vars. */ l->statics_read_by_decl_uid = BITMAP_GGC_ALLOC (); l->statics_written_by_decl_uid = BITMAP_GGC_ALLOC (); if (cgraph_dump_file) fprintf (cgraph_dump_file, "\n local analysis of %s", cgraph_node_name (fn)); walk_tree (&DECL_SAVED_TREE (decl), scan_for_static_refs, fn, visited_nodes); pointer_set_destroy (visited_nodes); visited_nodes = NULL; } /* Lookup the tree node for the static variable that has UID and conver the name to a string for debugging. */ static const char * cgraph_get_static_name_by_uid (int index) { splay_tree_node stn = splay_tree_lookup (static_vars_to_consider_by_uid, index); if (stn) return lang_hooks.decl_printable_name ((tree)(stn->value), 2); return NULL; } /* Clear out any the static variable with uid INDEX from further consideration because it escapes (i.e. has had its address taken). */ static void clear_static_vars_maps (int index) { splay_tree_node stn = splay_tree_lookup (static_vars_to_consider_by_uid, index); if (stn) { splay_tree_remove (static_vars_to_consider_by_tree, stn->value); splay_tree_remove (static_vars_to_consider_by_uid, index); } } /* FIXME -- PROFILE-RESTRUCTURE: Change all *_decl_uid to *_ann_uid. */ /* Or in all of the bits from every callee into X, the caller's, bit vector. There are several cases to check to avoid the sparse bitmap oring. */ static void cgraph_propagate_bits (struct cgraph_node *x) { static_vars_info_t x_info = x->static_vars_info; global_static_vars_info_t x_global = x_info->global; struct cgraph_edge *e; for (e = x->callees; e; e = e->next_callee) { struct cgraph_node *y = e->callee; /* We are only going to look at edges that point to nodes that have their output bit set. */ if (y->output) { static_vars_info_t y_info; global_static_vars_info_t y_global; y_info = y->static_vars_info; y_global = y_info->global; if (x_global->statics_read_by_decl_uid != all_module_statics) { if (y_global->statics_read_by_decl_uid == all_module_statics) x_global->statics_read_by_decl_uid = all_module_statics; /* Skip bitmaps that are pointer equal to node's bitmap (no reason to spin within the cycle). */ else if (x_global->statics_read_by_decl_uid != y_global->statics_read_by_decl_uid) bitmap_a_or_b (x_global->statics_read_by_decl_uid, x_global->statics_read_by_decl_uid, y_global->statics_read_by_decl_uid); } if (x_global->statics_written_by_decl_uid != all_module_statics) { if (y_global->statics_written_by_decl_uid == all_module_statics) x_global->statics_written_by_decl_uid = all_module_statics; /* Skip bitmaps that are pointer equal to node's bitmap (no reason to spin within the cycle). */ else if (x_global->statics_written_by_decl_uid != y_global->statics_written_by_decl_uid) bitmap_a_or_b (x_global->statics_written_by_decl_uid, x_global->statics_written_by_decl_uid, y_global->statics_written_by_decl_uid); } } } } /* FIXME -- PROFILE-RESTRUCTURE: Change all *_decl_uid to *_ann_uid except where noted below. */ /* The main routine for analyzing global static variable usage. See comments at top for description. */ static void cgraph_characterize_statics (void) { struct cgraph_node *node; struct cgraph_node *w; struct cgraph_node **order = xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *)); int order_pos = 0; int i; struct cgraph_varpool_node *vnode; tree global; /* get rid of the splay trees from the previous compilation unit. */ static_vars_to_consider_by_tree = splay_tree_new_ggc (splay_tree_compare_pointers); static_vars_to_consider_by_uid = splay_tree_new_ggc (splay_tree_compare_ints); if (module_statics_escape) { bitmap_clear (module_statics_escape); bitmap_clear (all_module_statics); } else { module_statics_escape = BITMAP_XMALLOC (); all_module_statics = BITMAP_GGC_ALLOC (); } /* Find all of the global variables that we wish to analyze. */ for (vnode = cgraph_varpool_nodes_queue; vnode; vnode = vnode->next_needed) { global = vnode->decl; if ((TREE_CODE (global) == VAR_DECL) && has_proper_scope_for_analysis (global)) { splay_tree_insert (static_vars_to_consider_by_tree, (splay_tree_key) global, (splay_tree_value) global); /* FIXME -- PROFILE-RESTRUCTURE: Change the call from DECL_UID to get the uid from the var_ann field. */ splay_tree_insert (static_vars_to_consider_by_uid, DECL_UID (global), (splay_tree_value)global); if (cgraph_dump_file) fprintf (cgraph_dump_file, "\nConsidering global:%s", lang_hooks.decl_printable_name (global, 2)); /* FIXME -- PROFILE-RESTRUCTURE: Change the call from DECL_UID to get the uid from the var_ann field. */ bitmap_set_bit (all_module_statics, DECL_UID (global)); } } order_pos = cgraph_reduced_inorder (order, false); if (cgraph_dump_file) print_order("new", order, order_pos); for (i = order_pos - 1; i >= 0; i--) { node = order[i]; /* Scan each function to determine the variable usage patterns. */ cgraph_characterize_statics_local (node); } /* Prune out the variables that were found to behave badly (i.e. have there address taken). */ { int index; bitmap_iterator bi; EXECUTE_IF_SET_IN_BITMAP (module_statics_escape, 0, index, bi) { clear_static_vars_maps (index); } bitmap_operation (all_module_statics, all_module_statics, module_statics_escape, BITMAP_AND_COMPL); for (i = order_pos - 1; i >= 0; i--) { local_static_vars_info_t l; node = order[i]; l = node->static_vars_info->local; bitmap_operation (l->statics_read_by_decl_uid, l->statics_read_by_decl_uid, module_statics_escape, BITMAP_AND_COMPL); bitmap_operation (l->statics_written_by_decl_uid, l->statics_written_by_decl_uid, module_statics_escape, BITMAP_AND_COMPL); } } if (cgraph_dump_file) { for (i = order_pos - 1; i >= 0; i--) { int index; local_static_vars_info_t l; bitmap_iterator bi; node = order[i]; l = node->static_vars_info->local; fprintf (cgraph_dump_file, "\nFunction name:%s/%i:", cgraph_node_name (node), node->uid); fprintf (cgraph_dump_file, "\n locals read: "); EXECUTE_IF_SET_IN_BITMAP (l->statics_read_by_decl_uid, 0, index, bi) { fprintf (cgraph_dump_file, "%s ", cgraph_get_static_name_by_uid (index)); } fprintf (cgraph_dump_file, "\n locals written: "); EXECUTE_IF_SET_IN_BITMAP (l->statics_written_by_decl_uid, 0, index, bi) { fprintf(cgraph_dump_file, "%s ", cgraph_get_static_name_by_uid (index)); } } } /* Propagate the local information thru the call graph to produce the global information. All the nodes within a cycle will have the same info so we collapse cycles first. Then we can do the propagation in one pass from the leaves to the roots. */ order_pos = cgraph_reduced_inorder (order, true); for (i = order_pos - 1; i >= 0; i--) { static_vars_info_t node_info; global_static_vars_info_t node_g = ggc_calloc (1, sizeof (struct global_static_vars_info_d)); local_static_vars_info_t node_l; bool read_all; bool write_all; node = order[i]; node_info = node->static_vars_info; node_info->global = node_g; node_l = node_info->local; read_all = node->local.calls_read_all; write_all = node->local.calls_write_all; /* If any node in a cycle is calls_read_all or calls_write_all they all are. */ w = node->next_cycle; while (w) { read_all |= w->local.calls_read_all; write_all |= w->local.calls_write_all; w = w->next_cycle; } /* Initialized the bitmaps for the reduced nodes */ if (read_all) node_g->statics_read_by_decl_uid = all_module_statics; else { node_g->statics_read_by_decl_uid = BITMAP_GGC_ALLOC (); bitmap_copy (node_g->statics_read_by_decl_uid, node_l->statics_read_by_decl_uid); } if (write_all) node_g->statics_written_by_decl_uid = all_module_statics; else { node_g->statics_written_by_decl_uid = BITMAP_GGC_ALLOC (); bitmap_copy (node_g->statics_written_by_decl_uid, node_l->statics_written_by_decl_uid); } w = node->next_cycle; while (w) { /* All nodes within a cycle share the same global info bitmaps. */ static_vars_info_t w_info = w->static_vars_info; local_static_vars_info_t w_l; w_info->global = node_g; w_l = w_info->local; /* These global bitmaps are initialized from the local info of all of the nodes in the region. However there is no need to do any work if the bitmaps were set to all_module_statics. */ if (!read_all) bitmap_a_or_b (node_g->statics_read_by_decl_uid, node_g->statics_read_by_decl_uid, w_l->statics_read_by_decl_uid); if (!write_all) bitmap_a_or_b (node_g->statics_written_by_decl_uid, node_g->statics_written_by_decl_uid, w_l->statics_written_by_decl_uid); w = w->next_cycle; } cgraph_propagate_bits (node); w = node->next_cycle; while (w) { cgraph_propagate_bits (w); w = w->next_cycle; } } if (cgraph_dump_file) { for (i = order_pos - 1; i >= 0; i--) { static_vars_info_t node_info; global_static_vars_info_t node_g; int index; bitmap_iterator bi; node = order[i]; node_info = node->static_vars_info; node_g = node_info->global; fprintf (cgraph_dump_file, "\nFunction name:%s/%i:", cgraph_node_name (node), node->uid); w = node->next_cycle; while (w) { fprintf (cgraph_dump_file, "\n next cycle: %s/%i ", cgraph_node_name (w), w->uid); w = w->next_cycle; } fprintf (cgraph_dump_file, "\n globals read: "); EXECUTE_IF_SET_IN_BITMAP (node_g->statics_read_by_decl_uid, 0, index, bi) { fprintf (cgraph_dump_file, "%s ", cgraph_get_static_name_by_uid (index)); } fprintf (cgraph_dump_file, "\n globals written: "); EXECUTE_IF_SET_IN_BITMAP (node_g->statics_written_by_decl_uid, 0, index, bi) { fprintf (cgraph_dump_file, "%s ", cgraph_get_static_name_by_uid (index)); } } } /* Cleanup. */ for (i = order_pos - 1; i >= 0; i--) { static_vars_info_t node_info; global_static_vars_info_t node_g; node = order[i]; node_info = node->static_vars_info; node_g = node_info->global; node_g->var_anns_valid = false; /* Create the complimentary sets. These are more useful for certain apis. */ node_g->statics_not_read_by_decl_uid = BITMAP_GGC_ALLOC (); node_g->statics_not_written_by_decl_uid = BITMAP_GGC_ALLOC (); /* FIXME -- PROFILE-RESTRUCTURE: Delete next 4 assignments. */ node_g->statics_read_by_ann_uid = BITMAP_GGC_ALLOC (); node_g->statics_written_by_ann_uid = BITMAP_GGC_ALLOC (); node_g->statics_not_read_by_ann_uid = BITMAP_GGC_ALLOC (); node_g->statics_not_written_by_ann_uid = BITMAP_GGC_ALLOC (); if (node_g->statics_read_by_decl_uid != all_module_statics) { bitmap_operation (node_g->statics_not_read_by_decl_uid, all_module_statics, node_g->statics_read_by_decl_uid, BITMAP_AND_COMPL); } if (node_g->statics_written_by_decl_uid != all_module_statics) bitmap_operation (node_g->statics_not_written_by_decl_uid, all_module_statics, node_g->statics_written_by_decl_uid, BITMAP_AND_COMPL); w = node->next_cycle; while (w) { struct cgraph_node * last = w; w = w->next_cycle; last->next_cycle = NULL; } } free (order); } /* Expand all functions that must be output. Attempt to topologically sort the nodes so function is output when all called functions are already assembled to allow data to be propagated across the callgraph. Use a stack to get smaller distance between a function and its callees (later we may choose to use a more sophisticated algorithm for function reordering; we will likely want to use subsections to make the output functions appear in top-down order). */ static void cgraph_expand_all_functions (void) { struct cgraph_node *node; struct cgraph_node **order = xcalloc (cgraph_n_nodes, sizeof (struct cgraph_node *)); int order_pos = 0, new_order_pos = 0; int i; order_pos = cgraph_postorder (order); gcc_assert (order_pos == cgraph_n_nodes); /* Garbage collector may remove inline clones we eliminate during optimization. So we must be sure to not reference them. */ for (i = 0; i < order_pos; i++) if (order[i]->output) order[new_order_pos++] = order[i]; for (i = new_order_pos - 1; i >= 0; i--) { node = order[i]; if (node->output) { gcc_assert (node->reachable); node->output = 0; cgraph_expand_function (node); } } free (order); } /* Mark all local and external functions. A local function is one whose calls can occur only in the current compilation unit and all its calls are explicit, so we can change its calling convention. We simply mark all static functions whose address is not taken as local. An external function is one whose body is outside the current compilation unit. */ static void cgraph_mark_local_and_external_functions (void) { struct cgraph_node *node; /* Figure out functions we want to assemble. */ for (node = cgraph_nodes; node; node = node->next) { node->local.local = (!node->needed && DECL_SAVED_TREE (node->decl) && !TREE_PUBLIC (node->decl)); node->local.external = (!DECL_SAVED_TREE (node->decl) && TREE_PUBLIC (node->decl)); } if (cgraph_dump_file) { fprintf (cgraph_dump_file, "\nMarking local functions:"); for (node = cgraph_nodes; node; node = node->next) if (node->local.local) fprintf (cgraph_dump_file, " %s", cgraph_node_name (node)); fprintf (cgraph_dump_file, "\n\n"); fprintf (cgraph_dump_file, "\nMarking external functions:"); for (node = cgraph_nodes; node; node = node->next) if (node->local.external) fprintf (cgraph_dump_file, " %s", cgraph_node_name (node)); fprintf (cgraph_dump_file, "\n\n"); } } /* Return true when function body of DECL still needs to be kept around for later re-use. */ bool cgraph_preserve_function_body_p (tree decl) { struct cgraph_node *node; /* Keep the body; we're going to dump it. */ if (dump_enabled_p (TDI_tree_all)) return true; if (!cgraph_global_info_ready) return (DECL_INLINE (decl) && !flag_really_no_inline); /* Look if there is any clone around. */ for (node = cgraph_node (decl); node; node = node->next_clone) if (node->global.inlined_to) return true; return false; } /* Perform simple optimizations based on callgraph. */ void cgraph_optimize (void) { #ifdef ENABLE_CHECKING verify_cgraph (); #endif if (!flag_unit_at_a_time) return; timevar_push (TV_CGRAPHOPT); if (!quiet_flag) fprintf (stderr, "Performing intraprocedural optimizations\n"); cgraph_mark_local_and_external_functions (); if (cgraph_dump_file) { fprintf (cgraph_dump_file, "Marked "); dump_cgraph (cgraph_dump_file); } if (flag_inline_trees) cgraph_decide_inlining (); cgraph_global_info_ready = true; if (cgraph_dump_file) { fprintf (cgraph_dump_file, "Optimized "); dump_cgraph (cgraph_dump_file); } timevar_pop (TV_CGRAPHOPT); /* Output everything. */ if (!quiet_flag) fprintf (stderr, "Assembling functions:\n"); #ifdef ENABLE_CHECKING verify_cgraph (); #endif /* This call was moved here from cgraph_expand_all_functions so that cgraph_characterize_statics could use the output flag of the cgraph node. */ cgraph_mark_functions_to_output (); cgraph_characterize_statics (); cgraph_expand_all_functions (); if (cgraph_dump_file) { fprintf (cgraph_dump_file, "\nFinal "); dump_cgraph (cgraph_dump_file); } #ifdef ENABLE_CHECKING verify_cgraph (); /* Double check that all inline clones are gone and that all function bodies have been released from memory. */ if (flag_unit_at_a_time && !dump_enabled_p (TDI_tree_all) && !(sorrycount || errorcount)) { struct cgraph_node *node; bool error_found = false; for (node = cgraph_nodes; node; node = node->next) if (node->analyzed && (node->global.inlined_to || DECL_SAVED_TREE (node->decl))) { error_found = true; dump_cgraph_node (stderr, node); } if (error_found) internal_error ("Nodes with no released memory found."); } #endif } /* Generate and emit a static constructor or destructor. WHICH must be one of 'I' or 'D'. BODY should be a STATEMENT_LIST containing GENERIC statements. */ void cgraph_build_static_cdtor (char which, tree body, int priority) { static int counter = 0; char which_buf[16]; tree decl, name, resdecl; sprintf (which_buf, "%c_%d", which, counter++); name = get_file_function_name_long (which_buf); decl = build_decl (FUNCTION_DECL, name, build_function_type (void_type_node, void_list_node)); current_function_decl = decl; resdecl = build_decl (RESULT_DECL, NULL_TREE, void_type_node); DECL_ARTIFICIAL (resdecl) = 1; DECL_IGNORED_P (resdecl) = 1; DECL_RESULT (decl) = resdecl; allocate_struct_function (decl); TREE_STATIC (decl) = 1; TREE_USED (decl) = 1; DECL_ARTIFICIAL (decl) = 1; DECL_IGNORED_P (decl) = 1; DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (decl) = 1; DECL_SAVED_TREE (decl) = body; TREE_PUBLIC (decl) = ! targetm.have_ctors_dtors; DECL_UNINLINABLE (decl) = 1; DECL_INITIAL (decl) = make_node (BLOCK); TREE_USED (DECL_INITIAL (decl)) = 1; DECL_SOURCE_LOCATION (decl) = input_location; cfun->function_end_locus = input_location; switch (which) { case 'I': DECL_STATIC_CONSTRUCTOR (decl) = 1; break; case 'D': DECL_STATIC_DESTRUCTOR (decl) = 1; break; default: gcc_unreachable (); } gimplify_function_tree (decl); /* ??? We will get called LATE in the compilation process. */ if (cgraph_global_info_ready) tree_rest_of_compilation (decl); else cgraph_finalize_function (decl, 0); if (targetm.have_ctors_dtors) { void (*fn) (rtx, int); if (which == 'I') fn = targetm.asm_out.constructor; else fn = targetm.asm_out.destructor; fn (XEXP (DECL_RTL (decl), 0), priority); } } void init_cgraph (void) { cgraph_dump_file = dump_begin (TDI_cgraph, NULL); memory_identifier = get_identifier("memory"); } #include "gt-cgraphunit.h"