------------------------------------------------------------------------------ -- -- -- GNAT COMPILER COMPONENTS -- -- -- -- I N L I N E -- -- -- -- B o d y -- -- -- -- Copyright (C) 1992-2017, 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 distributed with GNAT; see file COPYING3. If not, go to -- -- http://www.gnu.org/licenses for a complete copy of the license. -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with Aspects; use Aspects; with Atree; use Atree; with Debug; use Debug; with Einfo; use Einfo; with Elists; use Elists; with Errout; use Errout; with Expander; use Expander; with Exp_Ch6; use Exp_Ch6; with Exp_Ch7; use Exp_Ch7; with Exp_Tss; use Exp_Tss; with Exp_Util; use Exp_Util; with Fname; use Fname; with Fname.UF; use Fname.UF; with Lib; use Lib; with Namet; use Namet; with Nmake; use Nmake; with Nlists; use Nlists; with Output; use Output; with Sem_Aux; use Sem_Aux; with Sem_Ch8; use Sem_Ch8; with Sem_Ch10; use Sem_Ch10; with Sem_Ch12; use Sem_Ch12; with Sem_Prag; use Sem_Prag; with Sem_Util; use Sem_Util; with Sinfo; use Sinfo; with Sinput; use Sinput; with Snames; use Snames; with Stand; use Stand; with Uname; use Uname; with Tbuild; use Tbuild; package body Inline is Check_Inlining_Restrictions : constant Boolean := True; -- In the following cases the frontend rejects inlining because they -- are not handled well by the backend. This variable facilitates -- disabling these restrictions to evaluate future versions of the -- GCC backend in which some of the restrictions may be supported. -- -- - subprograms that have: -- - nested subprograms -- - instantiations -- - package declarations -- - task or protected object declarations -- - some of the following statements: -- - abort -- - asynchronous-select -- - conditional-entry-call -- - delay-relative -- - delay-until -- - selective-accept -- - timed-entry-call Inlined_Calls : Elist_Id; -- List of frontend inlined calls Backend_Calls : Elist_Id; -- List of inline calls passed to the backend Backend_Inlined_Subps : Elist_Id; -- List of subprograms inlined by the backend Backend_Not_Inlined_Subps : Elist_Id; -- List of subprograms that cannot be inlined by the backend -------------------- -- Inlined Bodies -- -------------------- -- Inlined functions are actually placed in line by the backend if the -- corresponding bodies are available (i.e. compiled). Whenever we find -- a call to an inlined subprogram, we add the name of the enclosing -- compilation unit to a worklist. After all compilation, and after -- expansion of generic bodies, we traverse the list of pending bodies -- and compile them as well. package Inlined_Bodies is new Table.Table ( Table_Component_Type => Entity_Id, Table_Index_Type => Int, Table_Low_Bound => 0, Table_Initial => Alloc.Inlined_Bodies_Initial, Table_Increment => Alloc.Inlined_Bodies_Increment, Table_Name => "Inlined_Bodies"); ----------------------- -- Inline Processing -- ----------------------- -- For each call to an inlined subprogram, we make entries in a table -- that stores caller and callee, and indicates the call direction from -- one to the other. We also record the compilation unit that contains -- the callee. After analyzing the bodies of all such compilation units, -- we compute the transitive closure of inlined subprograms called from -- the main compilation unit and make it available to the code generator -- in no particular order, thus allowing cycles in the call graph. Last_Inlined : Entity_Id := Empty; -- For each entry in the table we keep a list of successors in topological -- order, i.e. callers of the current subprogram. type Subp_Index is new Nat; No_Subp : constant Subp_Index := 0; -- The subprogram entities are hashed into the Inlined table Num_Hash_Headers : constant := 512; Hash_Headers : array (Subp_Index range 0 .. Num_Hash_Headers - 1) of Subp_Index; type Succ_Index is new Nat; No_Succ : constant Succ_Index := 0; type Succ_Info is record Subp : Subp_Index; Next : Succ_Index; end record; -- The following table stores list elements for the successor lists. These -- lists cannot be chained directly through entries in the Inlined table, -- because a given subprogram can appear in several such lists. package Successors is new Table.Table ( Table_Component_Type => Succ_Info, Table_Index_Type => Succ_Index, Table_Low_Bound => 1, Table_Initial => Alloc.Successors_Initial, Table_Increment => Alloc.Successors_Increment, Table_Name => "Successors"); type Subp_Info is record Name : Entity_Id := Empty; Next : Subp_Index := No_Subp; First_Succ : Succ_Index := No_Succ; Main_Call : Boolean := False; Processed : Boolean := False; end record; package Inlined is new Table.Table ( Table_Component_Type => Subp_Info, Table_Index_Type => Subp_Index, Table_Low_Bound => 1, Table_Initial => Alloc.Inlined_Initial, Table_Increment => Alloc.Inlined_Increment, Table_Name => "Inlined"); ----------------------- -- Local Subprograms -- ----------------------- procedure Add_Call (Called : Entity_Id; Caller : Entity_Id := Empty); -- Make two entries in Inlined table, for an inlined subprogram being -- called, and for the inlined subprogram that contains the call. If -- the call is in the main compilation unit, Caller is Empty. procedure Add_Inlined_Subprogram (E : Entity_Id); -- Add subprogram E to the list of inlined subprogram for the unit function Add_Subp (E : Entity_Id) return Subp_Index; -- Make entry in Inlined table for subprogram E, or return table index -- that already holds E. function Get_Code_Unit_Entity (E : Entity_Id) return Entity_Id; pragma Inline (Get_Code_Unit_Entity); -- Return the entity node for the unit containing E. Always return the spec -- for a package. function Has_Initialized_Type (E : Entity_Id) return Boolean; -- If a candidate for inlining contains type declarations for types with -- nontrivial initialization procedures, they are not worth inlining. function Has_Single_Return (N : Node_Id) return Boolean; -- In general we cannot inline functions that return unconstrained type. -- However, we can handle such functions if all return statements return a -- local variable that is the only declaration in the body of the function. -- In that case the call can be replaced by that local variable as is done -- for other inlined calls. function In_Main_Unit_Or_Subunit (E : Entity_Id) return Boolean; -- Return True if E is in the main unit or its spec or in a subunit function Is_Nested (E : Entity_Id) return Boolean; -- If the function is nested inside some other function, it will always -- be compiled if that function is, so don't add it to the inline list. -- We cannot compile a nested function outside the scope of the containing -- function anyway. This is also the case if the function is defined in a -- task body or within an entry (for example, an initialization procedure). procedure Remove_Aspects_And_Pragmas (Body_Decl : Node_Id); -- Remove all aspects and/or pragmas that have no meaning in inlined body -- Body_Decl. The analysis of these items is performed on the non-inlined -- body. The items currently removed are: -- Contract_Cases -- Global -- Depends -- Postcondition -- Precondition -- Refined_Global -- Refined_Depends -- Refined_Post -- Test_Case -- Unmodified -- Unreferenced ------------------------------ -- Deferred Cleanup Actions -- ------------------------------ -- The cleanup actions for scopes that contain instantiations is delayed -- until after expansion of those instantiations, because they may contain -- finalizable objects or tasks that affect the cleanup code. A scope -- that contains instantiations only needs to be finalized once, even -- if it contains more than one instance. We keep a list of scopes -- that must still be finalized, and call cleanup_actions after all -- the instantiations have been completed. To_Clean : Elist_Id; procedure Add_Scope_To_Clean (Inst : Entity_Id); -- Build set of scopes on which cleanup actions must be performed procedure Cleanup_Scopes; -- Complete cleanup actions on scopes that need it -------------- -- Add_Call -- -------------- procedure Add_Call (Called : Entity_Id; Caller : Entity_Id := Empty) is P1 : constant Subp_Index := Add_Subp (Called); P2 : Subp_Index; J : Succ_Index; begin if Present (Caller) then P2 := Add_Subp (Caller); -- Add P1 to the list of successors of P2, if not already there. -- Note that P2 may contain more than one call to P1, and only -- one needs to be recorded. J := Inlined.Table (P2).First_Succ; while J /= No_Succ loop if Successors.Table (J).Subp = P1 then return; end if; J := Successors.Table (J).Next; end loop; -- On exit, make a successor entry for P1 Successors.Increment_Last; Successors.Table (Successors.Last).Subp := P1; Successors.Table (Successors.Last).Next := Inlined.Table (P2).First_Succ; Inlined.Table (P2).First_Succ := Successors.Last; else Inlined.Table (P1).Main_Call := True; end if; end Add_Call; ---------------------- -- Add_Inlined_Body -- ---------------------- procedure Add_Inlined_Body (E : Entity_Id; N : Node_Id) is type Inline_Level_Type is (Dont_Inline, Inline_Call, Inline_Package); -- Level of inlining for the call: Dont_Inline means no inlining, -- Inline_Call means that only the call is considered for inlining, -- Inline_Package means that the call is considered for inlining and -- its package compiled and scanned for more inlining opportunities. function Must_Inline return Inline_Level_Type; -- Inlining is only done if the call statement N is in the main unit, -- or within the body of another inlined subprogram. ----------------- -- Must_Inline -- ----------------- function Must_Inline return Inline_Level_Type is Scop : Entity_Id; Comp : Node_Id; begin -- Check if call is in main unit Scop := Current_Scope; -- Do not try to inline if scope is standard. This could happen, for -- example, for a call to Add_Global_Declaration, and it causes -- trouble to try to inline at this level. if Scop = Standard_Standard then return Dont_Inline; end if; -- Otherwise lookup scope stack to outer scope while Scope (Scop) /= Standard_Standard and then not Is_Child_Unit (Scop) loop Scop := Scope (Scop); end loop; Comp := Parent (Scop); while Nkind (Comp) /= N_Compilation_Unit loop Comp := Parent (Comp); end loop; -- If the call is in the main unit, inline the call and compile the -- package of the subprogram to find more calls to be inlined. if Comp = Cunit (Main_Unit) or else Comp = Library_Unit (Cunit (Main_Unit)) then Add_Call (E); return Inline_Package; end if; -- The call is not in the main unit. See if it is in some subprogram -- that can be inlined outside its unit. If so, inline the call and, -- if the inlining level is set to 1, stop there; otherwise also -- compile the package as above. Scop := Current_Scope; while Scope (Scop) /= Standard_Standard and then not Is_Child_Unit (Scop) loop if Is_Overloadable (Scop) and then Is_Inlined (Scop) and then not Is_Nested (Scop) then Add_Call (E, Scop); if Inline_Level = 1 then return Inline_Call; else return Inline_Package; end if; end if; Scop := Scope (Scop); end loop; return Dont_Inline; end Must_Inline; Level : Inline_Level_Type; -- Start of processing for Add_Inlined_Body begin Append_New_Elmt (N, To => Backend_Calls); -- Skip subprograms that cannot be inlined outside their unit if Is_Abstract_Subprogram (E) or else Convention (E) = Convention_Protected or else Is_Nested (E) then return; end if; -- Find out whether the call must be inlined. Unless the result is -- Dont_Inline, Must_Inline also creates an edge for the call in the -- callgraph; however, it will not be activated until after Is_Called -- is set on the subprogram. Level := Must_Inline; if Level = Dont_Inline then return; end if; -- If the call was generated by the compiler and is to a subprogram in -- a run-time unit, we need to suppress debugging information for it, -- so that the code that is eventually inlined will not affect the -- debugging of the program. We do not do it if the call comes from -- source because, even if the call is inlined, the user may expect it -- to be present in the debugging information. if not Comes_From_Source (N) and then In_Extended_Main_Source_Unit (N) and then Is_Predefined_Unit (Get_Source_Unit (E)) then Set_Needs_Debug_Info (E, False); end if; -- If the subprogram is an expression function, then there is no need to -- load any package body since the body of the function is in the spec. if Is_Expression_Function (E) then Set_Is_Called (E); return; end if; -- Find unit containing E, and add to list of inlined bodies if needed. -- If the body is already present, no need to load any other unit. This -- is the case for an initialization procedure, which appears in the -- package declaration that contains the type. It is also the case if -- the body has already been analyzed. Finally, if the unit enclosing -- E is an instance, the instance body will be analyzed in any case, -- and there is no need to add the enclosing unit (whose body might not -- be available). -- Library-level functions must be handled specially, because there is -- no enclosing package to retrieve. In this case, it is the body of -- the function that will have to be loaded. declare Pack : constant Entity_Id := Get_Code_Unit_Entity (E); begin if Pack = E then Set_Is_Called (E); Inlined_Bodies.Increment_Last; Inlined_Bodies.Table (Inlined_Bodies.Last) := E; elsif Ekind (Pack) = E_Package then Set_Is_Called (E); if Is_Generic_Instance (Pack) then null; -- Do not inline the package if the subprogram is an init proc -- or other internally generated subprogram, because in that -- case the subprogram body appears in the same unit that -- declares the type, and that body is visible to the back end. -- Do not inline it either if it is in the main unit. -- Extend the -gnatn2 processing to -gnatn1 for Inline_Always -- calls if the back-end takes care of inlining the call. -- Note that Level in Inline_Package | Inline_Call here. elsif ((Level = Inline_Call and then Has_Pragma_Inline_Always (E) and then Back_End_Inlining) or else Level = Inline_Package) and then not Is_Inlined (Pack) and then not Is_Internal (E) and then not In_Main_Unit_Or_Subunit (Pack) then Set_Is_Inlined (Pack); Inlined_Bodies.Increment_Last; Inlined_Bodies.Table (Inlined_Bodies.Last) := Pack; end if; end if; -- Ensure that Analyze_Inlined_Bodies will be invoked after -- completing the analysis of the current unit. Inline_Processing_Required := True; end; end Add_Inlined_Body; ---------------------------- -- Add_Inlined_Subprogram -- ---------------------------- procedure Add_Inlined_Subprogram (E : Entity_Id) is Decl : constant Node_Id := Parent (Declaration_Node (E)); Pack : constant Entity_Id := Get_Code_Unit_Entity (E); procedure Register_Backend_Inlined_Subprogram (Subp : Entity_Id); -- Append Subp to the list of subprograms inlined by the backend procedure Register_Backend_Not_Inlined_Subprogram (Subp : Entity_Id); -- Append Subp to the list of subprograms that cannot be inlined by -- the backend. ----------------------------------------- -- Register_Backend_Inlined_Subprogram -- ----------------------------------------- procedure Register_Backend_Inlined_Subprogram (Subp : Entity_Id) is begin Append_New_Elmt (Subp, To => Backend_Inlined_Subps); end Register_Backend_Inlined_Subprogram; --------------------------------------------- -- Register_Backend_Not_Inlined_Subprogram -- --------------------------------------------- procedure Register_Backend_Not_Inlined_Subprogram (Subp : Entity_Id) is begin Append_New_Elmt (Subp, To => Backend_Not_Inlined_Subps); end Register_Backend_Not_Inlined_Subprogram; -- Start of processing for Add_Inlined_Subprogram begin -- If the subprogram is to be inlined, and if its unit is known to be -- inlined or is an instance whose body will be analyzed anyway or the -- subprogram was generated as a body by the compiler (for example an -- initialization procedure) or its declaration was provided along with -- the body (for example an expression function), and if it is declared -- at the library level not in the main unit, and if it can be inlined -- by the back-end, then insert it in the list of inlined subprograms. if Is_Inlined (E) and then (Is_Inlined (Pack) or else Is_Generic_Instance (Pack) or else Nkind (Decl) = N_Subprogram_Body or else Present (Corresponding_Body (Decl))) and then not In_Main_Unit_Or_Subunit (E) and then not Is_Nested (E) and then not Has_Initialized_Type (E) then Register_Backend_Inlined_Subprogram (E); if No (Last_Inlined) then Set_First_Inlined_Subprogram (Cunit (Main_Unit), E); else Set_Next_Inlined_Subprogram (Last_Inlined, E); end if; Last_Inlined := E; else Register_Backend_Not_Inlined_Subprogram (E); end if; end Add_Inlined_Subprogram; ------------------------ -- Add_Scope_To_Clean -- ------------------------ procedure Add_Scope_To_Clean (Inst : Entity_Id) is Scop : constant Entity_Id := Enclosing_Dynamic_Scope (Inst); Elmt : Elmt_Id; begin -- If the instance appears in a library-level package declaration, -- all finalization is global, and nothing needs doing here. if Scop = Standard_Standard then return; end if; -- If the instance is within a generic unit, no finalization code -- can be generated. Note that at this point all bodies have been -- analyzed, and the scope stack itself is not present, and the flag -- Inside_A_Generic is not set. declare S : Entity_Id; begin S := Scope (Inst); while Present (S) and then S /= Standard_Standard loop if Is_Generic_Unit (S) then return; end if; S := Scope (S); end loop; end; Elmt := First_Elmt (To_Clean); while Present (Elmt) loop if Node (Elmt) = Scop then return; end if; Elmt := Next_Elmt (Elmt); end loop; Append_Elmt (Scop, To_Clean); end Add_Scope_To_Clean; -------------- -- Add_Subp -- -------------- function Add_Subp (E : Entity_Id) return Subp_Index is Index : Subp_Index := Subp_Index (E) mod Num_Hash_Headers; J : Subp_Index; procedure New_Entry; -- Initialize entry in Inlined table procedure New_Entry is begin Inlined.Increment_Last; Inlined.Table (Inlined.Last).Name := E; Inlined.Table (Inlined.Last).Next := No_Subp; Inlined.Table (Inlined.Last).First_Succ := No_Succ; Inlined.Table (Inlined.Last).Main_Call := False; Inlined.Table (Inlined.Last).Processed := False; end New_Entry; -- Start of processing for Add_Subp begin if Hash_Headers (Index) = No_Subp then New_Entry; Hash_Headers (Index) := Inlined.Last; return Inlined.Last; else J := Hash_Headers (Index); while J /= No_Subp loop if Inlined.Table (J).Name = E then return J; else Index := J; J := Inlined.Table (J).Next; end if; end loop; -- On exit, subprogram was not found. Enter in table. Index is -- the current last entry on the hash chain. New_Entry; Inlined.Table (Index).Next := Inlined.Last; return Inlined.Last; end if; end Add_Subp; ---------------------------- -- Analyze_Inlined_Bodies -- ---------------------------- procedure Analyze_Inlined_Bodies is Comp_Unit : Node_Id; J : Int; Pack : Entity_Id; Subp : Subp_Index; S : Succ_Index; type Pending_Index is new Nat; package Pending_Inlined is new Table.Table ( Table_Component_Type => Subp_Index, Table_Index_Type => Pending_Index, Table_Low_Bound => 1, Table_Initial => Alloc.Inlined_Initial, Table_Increment => Alloc.Inlined_Increment, Table_Name => "Pending_Inlined"); -- The workpile used to compute the transitive closure -- Start of processing for Analyze_Inlined_Bodies begin if Serious_Errors_Detected = 0 then Push_Scope (Standard_Standard); J := 0; while J <= Inlined_Bodies.Last and then Serious_Errors_Detected = 0 loop Pack := Inlined_Bodies.Table (J); while Present (Pack) and then Scope (Pack) /= Standard_Standard and then not Is_Child_Unit (Pack) loop Pack := Scope (Pack); end loop; Comp_Unit := Parent (Pack); while Present (Comp_Unit) and then Nkind (Comp_Unit) /= N_Compilation_Unit loop Comp_Unit := Parent (Comp_Unit); end loop; -- Load the body if it exists and contains inlineable entities, -- unless it is the main unit, or is an instance whose body has -- already been analyzed. if Present (Comp_Unit) and then Comp_Unit /= Cunit (Main_Unit) and then Body_Required (Comp_Unit) and then (Nkind (Unit (Comp_Unit)) /= N_Package_Declaration or else (No (Corresponding_Body (Unit (Comp_Unit))) and then Body_Needed_For_Inlining (Defining_Entity (Unit (Comp_Unit))))) then declare Bname : constant Unit_Name_Type := Get_Body_Name (Get_Unit_Name (Unit (Comp_Unit))); OK : Boolean; begin if not Is_Loaded (Bname) then Style_Check := False; Load_Needed_Body (Comp_Unit, OK); if not OK then -- Warn that a body was not available for inlining -- by the back-end. Error_Msg_Unit_1 := Bname; Error_Msg_N ("one or more inlined subprograms accessed in $!??", Comp_Unit); Error_Msg_File_1 := Get_File_Name (Bname, Subunit => False); Error_Msg_N ("\but file{ was not found!??", Comp_Unit); end if; end if; end; end if; J := J + 1; if J > Inlined_Bodies.Last then -- The analysis of required bodies may have produced additional -- generic instantiations. To obtain further inlining, we need -- to perform another round of generic body instantiations. Instantiate_Bodies; -- Symmetrically, the instantiation of required generic bodies -- may have caused additional bodies to be inlined. To obtain -- further inlining, we keep looping over the inlined bodies. end if; end loop; -- The list of inlined subprograms is an overestimate, because it -- includes inlined functions called from functions that are compiled -- as part of an inlined package, but are not themselves called. An -- accurate computation of just those subprograms that are needed -- requires that we perform a transitive closure over the call graph, -- starting from calls in the main compilation unit. for Index in Inlined.First .. Inlined.Last loop if not Is_Called (Inlined.Table (Index).Name) then -- This means that Add_Inlined_Body added the subprogram to the -- table but wasn't able to handle its code unit. Do nothing. Inlined.Table (Index).Processed := True; elsif Inlined.Table (Index).Main_Call then Pending_Inlined.Increment_Last; Pending_Inlined.Table (Pending_Inlined.Last) := Index; Inlined.Table (Index).Processed := True; else Set_Is_Called (Inlined.Table (Index).Name, False); end if; end loop; -- Iterate over the workpile until it is emptied, propagating the -- Is_Called flag to the successors of the processed subprogram. while Pending_Inlined.Last >= Pending_Inlined.First loop Subp := Pending_Inlined.Table (Pending_Inlined.Last); Pending_Inlined.Decrement_Last; S := Inlined.Table (Subp).First_Succ; while S /= No_Succ loop Subp := Successors.Table (S).Subp; if not Inlined.Table (Subp).Processed then Set_Is_Called (Inlined.Table (Subp).Name); Pending_Inlined.Increment_Last; Pending_Inlined.Table (Pending_Inlined.Last) := Subp; Inlined.Table (Subp).Processed := True; end if; S := Successors.Table (S).Next; end loop; end loop; -- Finally add the called subprograms to the list of inlined -- subprograms for the unit. for Index in Inlined.First .. Inlined.Last loop if Is_Called (Inlined.Table (Index).Name) then Add_Inlined_Subprogram (Inlined.Table (Index).Name); end if; end loop; Pop_Scope; end if; end Analyze_Inlined_Bodies; -------------------------- -- Build_Body_To_Inline -- -------------------------- procedure Build_Body_To_Inline (N : Node_Id; Spec_Id : Entity_Id) is Decl : constant Node_Id := Unit_Declaration_Node (Spec_Id); Analysis_Status : constant Boolean := Full_Analysis; Original_Body : Node_Id; Body_To_Analyze : Node_Id; Max_Size : constant := 10; function Has_Pending_Instantiation return Boolean; -- If some enclosing body contains instantiations that appear before -- the corresponding generic body, the enclosing body has a freeze node -- so that it can be elaborated after the generic itself. This might -- conflict with subsequent inlinings, so that it is unsafe to try to -- inline in such a case. function Has_Single_Return_In_GNATprove_Mode return Boolean; -- This function is called only in GNATprove mode, and it returns -- True if the subprogram has no return statement or a single return -- statement as last statement. It returns False for subprogram with -- a single return as last statement inside one or more blocks, as -- inlining would generate gotos in that case as well (although the -- goto is useless in that case). function Uses_Secondary_Stack (Bod : Node_Id) return Boolean; -- If the body of the subprogram includes a call that returns an -- unconstrained type, the secondary stack is involved, and it -- is not worth inlining. ------------------------------- -- Has_Pending_Instantiation -- ------------------------------- function Has_Pending_Instantiation return Boolean is S : Entity_Id; begin S := Current_Scope; while Present (S) loop if Is_Compilation_Unit (S) or else Is_Child_Unit (S) then return False; elsif Ekind (S) = E_Package and then Has_Forward_Instantiation (S) then return True; end if; S := Scope (S); end loop; return False; end Has_Pending_Instantiation; ----------------------------------------- -- Has_Single_Return_In_GNATprove_Mode -- ----------------------------------------- function Has_Single_Return_In_GNATprove_Mode return Boolean is Body_To_Inline : constant Node_Id := N; Last_Statement : Node_Id := Empty; function Check_Return (N : Node_Id) return Traverse_Result; -- Returns OK on node N if this is not a return statement different -- from the last statement in the subprogram. ------------------ -- Check_Return -- ------------------ function Check_Return (N : Node_Id) return Traverse_Result is begin case Nkind (N) is when N_Extended_Return_Statement | N_Simple_Return_Statement => if N = Last_Statement then return OK; else return Abandon; end if; -- Skip locally declared subprogram bodies inside the body to -- inline, as the return statements inside those do not count. when N_Subprogram_Body => if N = Body_To_Inline then return OK; else return Skip; end if; when others => return OK; end case; end Check_Return; function Check_All_Returns is new Traverse_Func (Check_Return); -- Start of processing for Has_Single_Return_In_GNATprove_Mode begin -- Retrieve the last statement Last_Statement := Last (Statements (Handled_Statement_Sequence (N))); -- Check that the last statement is the only possible return -- statement in the subprogram. return Check_All_Returns (N) = OK; end Has_Single_Return_In_GNATprove_Mode; -------------------------- -- Uses_Secondary_Stack -- -------------------------- function Uses_Secondary_Stack (Bod : Node_Id) return Boolean is function Check_Call (N : Node_Id) return Traverse_Result; -- Look for function calls that return an unconstrained type ---------------- -- Check_Call -- ---------------- function Check_Call (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Function_Call and then Is_Entity_Name (Name (N)) and then Is_Composite_Type (Etype (Entity (Name (N)))) and then not Is_Constrained (Etype (Entity (Name (N)))) then Cannot_Inline ("cannot inline & (call returns unconstrained type)?", N, Spec_Id); return Abandon; else return OK; end if; end Check_Call; function Check_Calls is new Traverse_Func (Check_Call); begin return Check_Calls (Bod) = Abandon; end Uses_Secondary_Stack; -- Start of processing for Build_Body_To_Inline begin -- Return immediately if done already if Nkind (Decl) = N_Subprogram_Declaration and then Present (Body_To_Inline (Decl)) then return; -- Subprograms that have return statements in the middle of the body are -- inlined with gotos. GNATprove does not currently support gotos, so -- we prevent such inlining. elsif GNATprove_Mode and then not Has_Single_Return_In_GNATprove_Mode then Cannot_Inline ("cannot inline & (multiple returns)?", N, Spec_Id); return; -- Functions that return unconstrained composite types require -- secondary stack handling, and cannot currently be inlined, unless -- all return statements return a local variable that is the first -- local declaration in the body. elsif Ekind (Spec_Id) = E_Function and then not Is_Scalar_Type (Etype (Spec_Id)) and then not Is_Access_Type (Etype (Spec_Id)) and then not Is_Constrained (Etype (Spec_Id)) then if not Has_Single_Return (N) then Cannot_Inline ("cannot inline & (unconstrained return type)?", N, Spec_Id); return; end if; -- Ditto for functions that return controlled types, where controlled -- actions interfere in complex ways with inlining. elsif Ekind (Spec_Id) = E_Function and then Needs_Finalization (Etype (Spec_Id)) then Cannot_Inline ("cannot inline & (controlled return type)?", N, Spec_Id); return; end if; if Present (Declarations (N)) and then Has_Excluded_Declaration (Spec_Id, Declarations (N)) then return; end if; if Present (Handled_Statement_Sequence (N)) then if Present (Exception_Handlers (Handled_Statement_Sequence (N))) then Cannot_Inline ("cannot inline& (exception handler)?", First (Exception_Handlers (Handled_Statement_Sequence (N))), Spec_Id); return; elsif Has_Excluded_Statement (Spec_Id, Statements (Handled_Statement_Sequence (N))) then return; end if; end if; -- We do not inline a subprogram that is too large, unless it is marked -- Inline_Always or we are in GNATprove mode. This pragma does not -- suppress the other checks on inlining (forbidden declarations, -- handlers, etc). if not (Has_Pragma_Inline_Always (Spec_Id) or else GNATprove_Mode) and then List_Length (Statements (Handled_Statement_Sequence (N))) > Max_Size then Cannot_Inline ("cannot inline& (body too large)?", N, Spec_Id); return; end if; if Has_Pending_Instantiation then Cannot_Inline ("cannot inline& (forward instance within enclosing body)?", N, Spec_Id); return; end if; -- Within an instance, the body to inline must be treated as a nested -- generic, so that the proper global references are preserved. -- Note that we do not do this at the library level, because it is not -- needed, and furthermore this causes trouble if front-end inlining -- is activated (-gnatN). if In_Instance and then Scope (Current_Scope) /= Standard_Standard then Save_Env (Scope (Current_Scope), Scope (Current_Scope)); Original_Body := Copy_Generic_Node (N, Empty, Instantiating => True); else Original_Body := Copy_Separate_Tree (N); end if; -- We need to capture references to the formals in order to substitute -- the actuals at the point of inlining, i.e. instantiation. To treat -- the formals as globals to the body to inline, we nest it within a -- dummy parameterless subprogram, declared within the real one. To -- avoid generating an internal name (which is never public, and which -- affects serial numbers of other generated names), we use an internal -- symbol that cannot conflict with user declarations. Set_Parameter_Specifications (Specification (Original_Body), No_List); Set_Defining_Unit_Name (Specification (Original_Body), Make_Defining_Identifier (Sloc (N), Name_uParent)); Set_Corresponding_Spec (Original_Body, Empty); -- Remove all aspects/pragmas that have no meaning in an inlined body Remove_Aspects_And_Pragmas (Original_Body); Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, Instantiating => False); -- Set return type of function, which is also global and does not need -- to be resolved. if Ekind (Spec_Id) = E_Function then Set_Result_Definition (Specification (Body_To_Analyze), New_Occurrence_Of (Etype (Spec_Id), Sloc (N))); end if; if No (Declarations (N)) then Set_Declarations (N, New_List (Body_To_Analyze)); else Append (Body_To_Analyze, Declarations (N)); end if; -- The body to inline is pre-analyzed. In GNATprove mode we must disable -- full analysis as well so that light expansion does not take place -- either, and name resolution is unaffected. Expander_Mode_Save_And_Set (False); Full_Analysis := False; Analyze (Body_To_Analyze); Push_Scope (Defining_Entity (Body_To_Analyze)); Save_Global_References (Original_Body); End_Scope; Remove (Body_To_Analyze); Expander_Mode_Restore; Full_Analysis := Analysis_Status; -- Restore environment if previously saved if In_Instance and then Scope (Current_Scope) /= Standard_Standard then Restore_Env; end if; -- If secondary stack is used, there is no point in inlining. We have -- already issued the warning in this case, so nothing to do. if Uses_Secondary_Stack (Body_To_Analyze) then return; end if; Set_Body_To_Inline (Decl, Original_Body); Set_Ekind (Defining_Entity (Original_Body), Ekind (Spec_Id)); Set_Is_Inlined (Spec_Id); end Build_Body_To_Inline; ------------------------------------------- -- Call_Can_Be_Inlined_In_GNATprove_Mode -- ------------------------------------------- function Call_Can_Be_Inlined_In_GNATprove_Mode (N : Node_Id; Subp : Entity_Id) return Boolean is F : Entity_Id; A : Node_Id; begin F := First_Formal (Subp); A := First_Actual (N); while Present (F) loop if Ekind (F) /= E_Out_Parameter and then not Same_Type (Etype (F), Etype (A)) and then (Is_By_Reference_Type (Etype (A)) or else Is_Limited_Type (Etype (A))) then return False; end if; Next_Formal (F); Next_Actual (A); end loop; return True; end Call_Can_Be_Inlined_In_GNATprove_Mode; -------------------------------------- -- Can_Be_Inlined_In_GNATprove_Mode -- -------------------------------------- function Can_Be_Inlined_In_GNATprove_Mode (Spec_Id : Entity_Id; Body_Id : Entity_Id) return Boolean is function Has_Formal_With_Discriminant_Dependent_Fields (Id : Entity_Id) return Boolean; -- Returns true if the subprogram has at least one formal parameter of -- an unconstrained record type with per-object constraints on component -- types. function Has_Some_Contract (Id : Entity_Id) return Boolean; -- Return True if subprogram Id has any contract. The presence of -- Extensions_Visible or Volatile_Function is also considered as a -- contract here. function Is_Unit_Subprogram (Id : Entity_Id) return Boolean; -- Return True if subprogram Id defines a compilation unit -- Shouldn't this be in Sem_Aux??? function In_Package_Spec (Id : Entity_Id) return Boolean; -- Return True if subprogram Id is defined in the package specification, -- either its visible or private part. --------------------------------------------------- -- Has_Formal_With_Discriminant_Dependent_Fields -- --------------------------------------------------- function Has_Formal_With_Discriminant_Dependent_Fields (Id : Entity_Id) return Boolean is function Has_Discriminant_Dependent_Component (Typ : Entity_Id) return Boolean; -- Determine whether unconstrained record type Typ has at least one -- component that depends on a discriminant. ------------------------------------------ -- Has_Discriminant_Dependent_Component -- ------------------------------------------ function Has_Discriminant_Dependent_Component (Typ : Entity_Id) return Boolean is Comp : Entity_Id; begin -- Inspect all components of the record type looking for one that -- depends on a discriminant. Comp := First_Component (Typ); while Present (Comp) loop if Has_Discriminant_Dependent_Constraint (Comp) then return True; end if; Next_Component (Comp); end loop; return False; end Has_Discriminant_Dependent_Component; -- Local variables Subp_Id : constant Entity_Id := Ultimate_Alias (Id); Formal : Entity_Id; Formal_Typ : Entity_Id; -- Start of processing for -- Has_Formal_With_Discriminant_Dependent_Fields begin -- Inspect all parameters of the subprogram looking for a formal -- of an unconstrained record type with at least one discriminant -- dependent component. Formal := First_Formal (Subp_Id); while Present (Formal) loop Formal_Typ := Etype (Formal); if Is_Record_Type (Formal_Typ) and then not Is_Constrained (Formal_Typ) and then Has_Discriminant_Dependent_Component (Formal_Typ) then return True; end if; Next_Formal (Formal); end loop; return False; end Has_Formal_With_Discriminant_Dependent_Fields; ----------------------- -- Has_Some_Contract -- ----------------------- function Has_Some_Contract (Id : Entity_Id) return Boolean is Items : Node_Id; begin -- A call to an expression function may precede the actual body which -- is inserted at the end of the enclosing declarations. Ensure that -- the related entity is decorated before inspecting the contract. if Is_Subprogram_Or_Generic_Subprogram (Id) then Items := Contract (Id); -- Note that Classifications is not Empty when Extensions_Visible -- or Volatile_Function is present, which causes such subprograms -- to be considered to have a contract here. This is fine as we -- want to avoid inlining these too. return Present (Items) and then (Present (Pre_Post_Conditions (Items)) or else Present (Contract_Test_Cases (Items)) or else Present (Classifications (Items))); end if; return False; end Has_Some_Contract; --------------------- -- In_Package_Spec -- --------------------- function In_Package_Spec (Id : Entity_Id) return Boolean is P : constant Node_Id := Parent (Subprogram_Spec (Id)); -- Parent of the subprogram's declaration begin return Nkind (Enclosing_Declaration (P)) = N_Package_Declaration; end In_Package_Spec; ------------------------ -- Is_Unit_Subprogram -- ------------------------ function Is_Unit_Subprogram (Id : Entity_Id) return Boolean is Decl : Node_Id := Parent (Parent (Id)); begin if Nkind (Parent (Id)) = N_Defining_Program_Unit_Name then Decl := Parent (Decl); end if; return Nkind (Parent (Decl)) = N_Compilation_Unit; end Is_Unit_Subprogram; -- Local declarations Id : Entity_Id; -- Procedure or function entity for the subprogram -- Start of processing for Can_Be_Inlined_In_GNATprove_Mode begin pragma Assert (Present (Spec_Id) or else Present (Body_Id)); if Present (Spec_Id) then Id := Spec_Id; else Id := Body_Id; end if; -- Only local subprograms without contracts are inlined in GNATprove -- mode, as these are the subprograms which a user is not interested in -- analyzing in isolation, but rather in the context of their call. This -- is a convenient convention, that could be changed for an explicit -- pragma/aspect one day. -- In a number of special cases, inlining is not desirable or not -- possible, see below. -- Do not inline unit-level subprograms if Is_Unit_Subprogram (Id) then return False; -- Do not inline subprograms declared in package specs, because they are -- not local, i.e. can be called either from anywhere (if declared in -- visible part) or from the child units (if declared in private part). elsif In_Package_Spec (Id) then return False; -- Do not inline subprograms declared in other units. This is important -- in particular for subprograms defined in the private part of a -- package spec, when analyzing one of its child packages, as otherwise -- we issue spurious messages about the impossibility to inline such -- calls. elsif not In_Extended_Main_Code_Unit (Id) then return False; -- Do not inline subprograms marked No_Return, possibly used for -- signaling errors, which GNATprove handles specially. elsif No_Return (Id) then return False; -- Do not inline subprograms that have a contract on the spec or the -- body. Use the contract(s) instead in GNATprove. This also prevents -- inlining of subprograms with Extensions_Visible or Volatile_Function. elsif (Present (Spec_Id) and then Has_Some_Contract (Spec_Id)) or else (Present (Body_Id) and then Has_Some_Contract (Body_Id)) then return False; -- Do not inline expression functions, which are directly inlined at the -- prover level. elsif (Present (Spec_Id) and then Is_Expression_Function (Spec_Id)) or else (Present (Body_Id) and then Is_Expression_Function (Body_Id)) then return False; -- Do not inline generic subprogram instances. The visibility rules of -- generic instances plays badly with inlining. elsif Is_Generic_Instance (Spec_Id) then return False; -- Only inline subprograms whose spec is marked SPARK_Mode On. For -- the subprogram body, a similar check is performed after the body -- is analyzed, as this is where a pragma SPARK_Mode might be inserted. elsif Present (Spec_Id) and then (No (SPARK_Pragma (Spec_Id)) or else Get_SPARK_Mode_From_Annotation (SPARK_Pragma (Spec_Id)) /= On) then return False; -- Subprograms in generic instances are currently not inlined, to avoid -- problems with inlining of standard library subprograms. elsif Instantiation_Location (Sloc (Id)) /= No_Location then return False; -- Do not inline subprograms and entries defined inside protected types, -- which typically are not helper subprograms, which also avoids getting -- spurious messages on calls that cannot be inlined. elsif Within_Protected_Type (Id) then return False; -- Do not inline predicate functions (treated specially by GNATprove) elsif Is_Predicate_Function (Id) then return False; -- Do not inline subprograms with a parameter of an unconstrained -- record type if it has discrimiant dependent fields. Indeed, with -- such parameters, the frontend cannot always ensure type compliance -- in record component accesses (in particular with records containing -- packed arrays). elsif Has_Formal_With_Discriminant_Dependent_Fields (Id) then return False; -- Otherwise, this is a subprogram declared inside the private part of a -- package, or inside a package body, or locally in a subprogram, and it -- does not have any contract. Inline it. else return True; end if; end Can_Be_Inlined_In_GNATprove_Mode; ------------------- -- Cannot_Inline -- ------------------- procedure Cannot_Inline (Msg : String; N : Node_Id; Subp : Entity_Id; Is_Serious : Boolean := False) is begin -- In GNATprove mode, inlining is the technical means by which the -- higher-level goal of contextual analysis is reached, so issue -- messages about failure to apply contextual analysis to a -- subprogram, rather than failure to inline it. if GNATprove_Mode and then Msg (Msg'First .. Msg'First + 12) = "cannot inline" then declare Len1 : constant Positive := String (String'("cannot inline"))'Length; Len2 : constant Positive := String (String'("info: no contextual analysis of"))'Length; New_Msg : String (1 .. Msg'Length + Len2 - Len1); begin New_Msg (1 .. Len2) := "info: no contextual analysis of"; New_Msg (Len2 + 1 .. Msg'Length + Len2 - Len1) := Msg (Msg'First + Len1 .. Msg'Last); Cannot_Inline (New_Msg, N, Subp, Is_Serious); return; end; end if; pragma Assert (Msg (Msg'Last) = '?'); -- Legacy front-end inlining model if not Back_End_Inlining then -- Do not emit warning if this is a predefined unit which is not -- the main unit. With validity checks enabled, some predefined -- subprograms may contain nested subprograms and become ineligible -- for inlining. if Is_Predefined_Unit (Get_Source_Unit (Subp)) and then not In_Extended_Main_Source_Unit (Subp) then null; -- In GNATprove mode, issue a warning, and indicate that the -- subprogram is not always inlined by setting flag Is_Inlined_Always -- to False. elsif GNATprove_Mode then Set_Is_Inlined_Always (Subp, False); Error_Msg_NE (Msg & "p?", N, Subp); elsif Has_Pragma_Inline_Always (Subp) then -- Remove last character (question mark) to make this into an -- error, because the Inline_Always pragma cannot be obeyed. Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp); elsif Ineffective_Inline_Warnings then Error_Msg_NE (Msg & "p?", N, Subp); end if; -- New semantics relying on back-end inlining elsif Is_Serious then -- Remove last character (question mark) to make this into an error. Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp); -- In GNATprove mode, issue a warning, and indicate that the subprogram -- is not always inlined by setting flag Is_Inlined_Always to False. elsif GNATprove_Mode then Set_Is_Inlined_Always (Subp, False); Error_Msg_NE (Msg & "p?", N, Subp); else -- Do not emit warning if this is a predefined unit which is not -- the main unit. This behavior is currently provided for backward -- compatibility but it will be removed when we enforce the -- strictness of the new rules. if Is_Predefined_Unit (Get_Source_Unit (Subp)) and then not In_Extended_Main_Source_Unit (Subp) then null; elsif Has_Pragma_Inline_Always (Subp) then -- Emit a warning if this is a call to a runtime subprogram -- which is located inside a generic. Previously this call -- was silently skipped. if Is_Generic_Instance (Subp) then declare Gen_P : constant Entity_Id := Generic_Parent (Parent (Subp)); begin if Is_Predefined_Unit (Get_Source_Unit (Gen_P)) then Set_Is_Inlined (Subp, False); Error_Msg_NE (Msg & "p?", N, Subp); return; end if; end; end if; -- Remove last character (question mark) to make this into an -- error, because the Inline_Always pragma cannot be obeyed. Error_Msg_NE (Msg (Msg'First .. Msg'Last - 1), N, Subp); else Set_Is_Inlined (Subp, False); if Ineffective_Inline_Warnings then Error_Msg_NE (Msg & "p?", N, Subp); end if; end if; end if; end Cannot_Inline; -------------------------------------------- -- Check_And_Split_Unconstrained_Function -- -------------------------------------------- procedure Check_And_Split_Unconstrained_Function (N : Node_Id; Spec_Id : Entity_Id; Body_Id : Entity_Id) is procedure Build_Body_To_Inline (N : Node_Id; Spec_Id : Entity_Id); -- Use generic machinery to build an unexpanded body for the subprogram. -- This body is subsequently used for inline expansions at call sites. function Can_Split_Unconstrained_Function (N : Node_Id) return Boolean; -- Return true if we generate code for the function body N, the function -- body N has no local declarations and its unique statement is a single -- extended return statement with a handled statements sequence. procedure Split_Unconstrained_Function (N : Node_Id; Spec_Id : Entity_Id); -- N is an inlined function body that returns an unconstrained type and -- has a single extended return statement. Split N in two subprograms: -- a procedure P' and a function F'. The formals of P' duplicate the -- formals of N plus an extra formal which is used to return a value; -- its body is composed by the declarations and list of statements -- of the extended return statement of N. -------------------------- -- Build_Body_To_Inline -- -------------------------- procedure Build_Body_To_Inline (N : Node_Id; Spec_Id : Entity_Id) is procedure Generate_Subprogram_Body (N : Node_Id; Body_To_Inline : out Node_Id); -- Generate a parameterless duplicate of subprogram body N. Note that -- occurrences of pragmas referencing the formals are removed since -- they have no meaning when the body is inlined and the formals are -- rewritten (the analysis of the non-inlined body will handle these -- pragmas). A new internal name is associated with Body_To_Inline. ----------------------------- -- Generate_Body_To_Inline -- ----------------------------- procedure Generate_Subprogram_Body (N : Node_Id; Body_To_Inline : out Node_Id) is begin -- Within an instance, the body to inline must be treated as a -- nested generic so that proper global references are preserved. -- Note that we do not do this at the library level, because it -- is not needed, and furthermore this causes trouble if front -- end inlining is activated (-gnatN). if In_Instance and then Scope (Current_Scope) /= Standard_Standard then Body_To_Inline := Copy_Generic_Node (N, Empty, Instantiating => True); else Body_To_Inline := Copy_Separate_Tree (N); end if; -- Remove aspects/pragmas that have no meaning in an inlined body Remove_Aspects_And_Pragmas (Body_To_Inline); -- We need to capture references to the formals in order -- to substitute the actuals at the point of inlining, i.e. -- instantiation. To treat the formals as globals to the body to -- inline, we nest it within a dummy parameterless subprogram, -- declared within the real one. Set_Parameter_Specifications (Specification (Body_To_Inline), No_List); -- A new internal name is associated with Body_To_Inline to avoid -- conflicts when the non-inlined body N is analyzed. Set_Defining_Unit_Name (Specification (Body_To_Inline), Make_Defining_Identifier (Sloc (N), New_Internal_Name ('P'))); Set_Corresponding_Spec (Body_To_Inline, Empty); end Generate_Subprogram_Body; -- Local variables Decl : constant Node_Id := Unit_Declaration_Node (Spec_Id); Original_Body : Node_Id; Body_To_Analyze : Node_Id; begin pragma Assert (Current_Scope = Spec_Id); -- Within an instance, the body to inline must be treated as a nested -- generic, so that the proper global references are preserved. We -- do not do this at the library level, because it is not needed, and -- furthermore this causes trouble if front-end inlining is activated -- (-gnatN). if In_Instance and then Scope (Current_Scope) /= Standard_Standard then Save_Env (Scope (Current_Scope), Scope (Current_Scope)); end if; -- Capture references to formals in order to substitute the actuals -- at the point of inlining or instantiation. To treat the formals -- as globals to the body to inline, nest the body within a dummy -- parameterless subprogram, declared within the real one. Generate_Subprogram_Body (N, Original_Body); Body_To_Analyze := Copy_Generic_Node (Original_Body, Empty, Instantiating => False); -- Set return type of function, which is also global and does not -- need to be resolved. if Ekind (Spec_Id) = E_Function then Set_Result_Definition (Specification (Body_To_Analyze), New_Occurrence_Of (Etype (Spec_Id), Sloc (N))); end if; if No (Declarations (N)) then Set_Declarations (N, New_List (Body_To_Analyze)); else Append_To (Declarations (N), Body_To_Analyze); end if; Preanalyze (Body_To_Analyze); Push_Scope (Defining_Entity (Body_To_Analyze)); Save_Global_References (Original_Body); End_Scope; Remove (Body_To_Analyze); -- Restore environment if previously saved if In_Instance and then Scope (Current_Scope) /= Standard_Standard then Restore_Env; end if; pragma Assert (No (Body_To_Inline (Decl))); Set_Body_To_Inline (Decl, Original_Body); Set_Ekind (Defining_Entity (Original_Body), Ekind (Spec_Id)); end Build_Body_To_Inline; -------------------------------------- -- Can_Split_Unconstrained_Function -- -------------------------------------- function Can_Split_Unconstrained_Function (N : Node_Id) return Boolean is Ret_Node : constant Node_Id := First (Statements (Handled_Statement_Sequence (N))); D : Node_Id; begin -- No user defined declarations allowed in the function except inside -- the unique return statement; implicit labels are the only allowed -- declarations. if not Is_Empty_List (Declarations (N)) then D := First (Declarations (N)); while Present (D) loop if Nkind (D) /= N_Implicit_Label_Declaration then return False; end if; Next (D); end loop; end if; -- We only split the inlined function when we are generating the code -- of its body; otherwise we leave duplicated split subprograms in -- the tree which (if referenced) generate wrong references at link -- time. return In_Extended_Main_Code_Unit (N) and then Present (Ret_Node) and then Nkind (Ret_Node) = N_Extended_Return_Statement and then No (Next (Ret_Node)) and then Present (Handled_Statement_Sequence (Ret_Node)); end Can_Split_Unconstrained_Function; ---------------------------------- -- Split_Unconstrained_Function -- ---------------------------------- procedure Split_Unconstrained_Function (N : Node_Id; Spec_Id : Entity_Id) is Loc : constant Source_Ptr := Sloc (N); Ret_Node : constant Node_Id := First (Statements (Handled_Statement_Sequence (N))); Ret_Obj : constant Node_Id := First (Return_Object_Declarations (Ret_Node)); procedure Build_Procedure (Proc_Id : out Entity_Id; Decl_List : out List_Id); -- Build a procedure containing the statements found in the extended -- return statement of the unconstrained function body N. --------------------- -- Build_Procedure -- --------------------- procedure Build_Procedure (Proc_Id : out Entity_Id; Decl_List : out List_Id) is Formal : Entity_Id; Formal_List : constant List_Id := New_List; Proc_Spec : Node_Id; Proc_Body : Node_Id; Subp_Name : constant Name_Id := New_Internal_Name ('F'); Body_Decl_List : List_Id := No_List; Param_Type : Node_Id; begin if Nkind (Object_Definition (Ret_Obj)) = N_Identifier then Param_Type := New_Copy (Object_Definition (Ret_Obj)); else Param_Type := New_Copy (Subtype_Mark (Object_Definition (Ret_Obj))); end if; Append_To (Formal_List, Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Chars => Chars (Defining_Identifier (Ret_Obj))), In_Present => False, Out_Present => True, Null_Exclusion_Present => False, Parameter_Type => Param_Type)); Formal := First_Formal (Spec_Id); -- Note that we copy the parameter type rather than creating -- a reference to it, because it may be a class-wide entity -- that will not be retrieved by name. while Present (Formal) loop Append_To (Formal_List, Make_Parameter_Specification (Loc, Defining_Identifier => Make_Defining_Identifier (Sloc (Formal), Chars => Chars (Formal)), In_Present => In_Present (Parent (Formal)), Out_Present => Out_Present (Parent (Formal)), Null_Exclusion_Present => Null_Exclusion_Present (Parent (Formal)), Parameter_Type => New_Copy_Tree (Parameter_Type (Parent (Formal))), Expression => Copy_Separate_Tree (Expression (Parent (Formal))))); Next_Formal (Formal); end loop; Proc_Id := Make_Defining_Identifier (Loc, Chars => Subp_Name); Proc_Spec := Make_Procedure_Specification (Loc, Defining_Unit_Name => Proc_Id, Parameter_Specifications => Formal_List); Decl_List := New_List; Append_To (Decl_List, Make_Subprogram_Declaration (Loc, Proc_Spec)); -- Can_Convert_Unconstrained_Function checked that the function -- has no local declarations except implicit label declarations. -- Copy these declarations to the built procedure. if Present (Declarations (N)) then Body_Decl_List := New_List; declare D : Node_Id; New_D : Node_Id; begin D := First (Declarations (N)); while Present (D) loop pragma Assert (Nkind (D) = N_Implicit_Label_Declaration); New_D := Make_Implicit_Label_Declaration (Loc, Make_Defining_Identifier (Loc, Chars => Chars (Defining_Identifier (D))), Label_Construct => Empty); Append_To (Body_Decl_List, New_D); Next (D); end loop; end; end if; pragma Assert (Present (Handled_Statement_Sequence (Ret_Node))); Proc_Body := Make_Subprogram_Body (Loc, Specification => Copy_Separate_Tree (Proc_Spec), Declarations => Body_Decl_List, Handled_Statement_Sequence => Copy_Separate_Tree (Handled_Statement_Sequence (Ret_Node))); Set_Defining_Unit_Name (Specification (Proc_Body), Make_Defining_Identifier (Loc, Subp_Name)); Append_To (Decl_List, Proc_Body); end Build_Procedure; -- Local variables New_Obj : constant Node_Id := Copy_Separate_Tree (Ret_Obj); Blk_Stmt : Node_Id; Proc_Id : Entity_Id; Proc_Call : Node_Id; -- Start of processing for Split_Unconstrained_Function begin -- Build the associated procedure, analyze it and insert it before -- the function body N. declare Scope : constant Entity_Id := Current_Scope; Decl_List : List_Id; begin Pop_Scope; Build_Procedure (Proc_Id, Decl_List); Insert_Actions (N, Decl_List); Set_Is_Inlined (Proc_Id); Push_Scope (Scope); end; -- Build the call to the generated procedure declare Actual_List : constant List_Id := New_List; Formal : Entity_Id; begin Append_To (Actual_List, New_Occurrence_Of (Defining_Identifier (New_Obj), Loc)); Formal := First_Formal (Spec_Id); while Present (Formal) loop Append_To (Actual_List, New_Occurrence_Of (Formal, Loc)); -- Avoid spurious warning on unreferenced formals Set_Referenced (Formal); Next_Formal (Formal); end loop; Proc_Call := Make_Procedure_Call_Statement (Loc, Name => New_Occurrence_Of (Proc_Id, Loc), Parameter_Associations => Actual_List); end; -- Generate: -- declare -- New_Obj : ... -- begin -- Proc (New_Obj, ...); -- return New_Obj; -- end; Blk_Stmt := Make_Block_Statement (Loc, Declarations => New_List (New_Obj), Handled_Statement_Sequence => Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List ( Proc_Call, Make_Simple_Return_Statement (Loc, Expression => New_Occurrence_Of (Defining_Identifier (New_Obj), Loc))))); Rewrite (Ret_Node, Blk_Stmt); end Split_Unconstrained_Function; -- Local variables Decl : constant Node_Id := Unit_Declaration_Node (Spec_Id); -- Start of processing for Check_And_Split_Unconstrained_Function begin pragma Assert (Back_End_Inlining and then Ekind (Spec_Id) = E_Function and then Returns_Unconstrained_Type (Spec_Id) and then Comes_From_Source (Body_Id) and then (Has_Pragma_Inline_Always (Spec_Id) or else Optimization_Level > 0)); -- This routine must not be used in GNATprove mode since GNATprove -- relies on frontend inlining pragma Assert (not GNATprove_Mode); -- No need to split the function if we cannot generate the code if Serious_Errors_Detected /= 0 then return; end if; -- No action needed in stubs since the attribute Body_To_Inline -- is not available if Nkind (Decl) = N_Subprogram_Body_Stub then return; -- Cannot build the body to inline if the attribute is already set. -- This attribute may have been set if this is a subprogram renaming -- declarations (see Freeze.Build_Renamed_Body). elsif Present (Body_To_Inline (Decl)) then return; -- Check excluded declarations elsif Present (Declarations (N)) and then Has_Excluded_Declaration (Spec_Id, Declarations (N)) then return; -- Check excluded statements. There is no need to protect us against -- exception handlers since they are supported by the GCC backend. elsif Present (Handled_Statement_Sequence (N)) and then Has_Excluded_Statement (Spec_Id, Statements (Handled_Statement_Sequence (N))) then return; end if; -- Build the body to inline only if really needed if Can_Split_Unconstrained_Function (N) then Split_Unconstrained_Function (N, Spec_Id); Build_Body_To_Inline (N, Spec_Id); Set_Is_Inlined (Spec_Id); end if; end Check_And_Split_Unconstrained_Function; ------------------------------------- -- Check_Package_Body_For_Inlining -- ------------------------------------- procedure Check_Package_Body_For_Inlining (N : Node_Id; P : Entity_Id) is Bname : Unit_Name_Type; E : Entity_Id; OK : Boolean; begin -- Legacy implementation (relying on frontend inlining) if not Back_End_Inlining and then Is_Compilation_Unit (P) and then not Is_Generic_Instance (P) then Bname := Get_Body_Name (Get_Unit_Name (Unit (N))); E := First_Entity (P); while Present (E) loop if Has_Pragma_Inline_Always (E) or else (Has_Pragma_Inline (E) and Front_End_Inlining) then if not Is_Loaded (Bname) then Load_Needed_Body (N, OK); if OK then -- Check we are not trying to inline a parent whose body -- depends on a child, when we are compiling the body of -- the child. Otherwise we have a potential elaboration -- circularity with inlined subprograms and with -- Taft-Amendment types. declare Comp : Node_Id; -- Body just compiled Child_Spec : Entity_Id; -- Spec of main unit Ent : Entity_Id; -- For iteration With_Clause : Node_Id; -- Context of body. begin if Nkind (Unit (Cunit (Main_Unit))) = N_Package_Body and then Present (Body_Entity (P)) then Child_Spec := Defining_Entity ((Unit (Library_Unit (Cunit (Main_Unit))))); Comp := Parent (Unit_Declaration_Node (Body_Entity (P))); -- Check whether the context of the body just -- compiled includes a child of itself, and that -- child is the spec of the main compilation. With_Clause := First (Context_Items (Comp)); while Present (With_Clause) loop if Nkind (With_Clause) = N_With_Clause and then Scope (Entity (Name (With_Clause))) = P and then Entity (Name (With_Clause)) = Child_Spec then Error_Msg_Node_2 := Child_Spec; Error_Msg_NE ("body of & depends on child unit&??", With_Clause, P); Error_Msg_N ("\subprograms in body cannot be inlined??", With_Clause); -- Disable further inlining from this unit, -- and keep Taft-amendment types incomplete. Ent := First_Entity (P); while Present (Ent) loop if Is_Type (Ent) and then Has_Completion_In_Body (Ent) then Set_Full_View (Ent, Empty); elsif Is_Subprogram (Ent) then Set_Is_Inlined (Ent, False); end if; Next_Entity (Ent); end loop; return; end if; Next (With_Clause); end loop; end if; end; elsif Ineffective_Inline_Warnings then Error_Msg_Unit_1 := Bname; Error_Msg_N ("unable to inline subprograms defined in $??", P); Error_Msg_N ("\body not found??", P); return; end if; end if; return; end if; Next_Entity (E); end loop; end if; end Check_Package_Body_For_Inlining; -------------------- -- Cleanup_Scopes -- -------------------- procedure Cleanup_Scopes is Elmt : Elmt_Id; Decl : Node_Id; Scop : Entity_Id; begin Elmt := First_Elmt (To_Clean); while Present (Elmt) loop Scop := Node (Elmt); if Ekind (Scop) = E_Entry then Scop := Protected_Body_Subprogram (Scop); elsif Is_Subprogram (Scop) and then Is_Protected_Type (Scope (Scop)) and then Present (Protected_Body_Subprogram (Scop)) then -- If a protected operation contains an instance, its cleanup -- operations have been delayed, and the subprogram has been -- rewritten in the expansion of the enclosing protected body. It -- is the corresponding subprogram that may require the cleanup -- operations, so propagate the information that triggers cleanup -- activity. Set_Uses_Sec_Stack (Protected_Body_Subprogram (Scop), Uses_Sec_Stack (Scop)); Scop := Protected_Body_Subprogram (Scop); end if; if Ekind (Scop) = E_Block then Decl := Parent (Block_Node (Scop)); else Decl := Unit_Declaration_Node (Scop); if Nkind_In (Decl, N_Subprogram_Declaration, N_Task_Type_Declaration, N_Subprogram_Body_Stub) then Decl := Unit_Declaration_Node (Corresponding_Body (Decl)); end if; end if; Push_Scope (Scop); Expand_Cleanup_Actions (Decl); End_Scope; Elmt := Next_Elmt (Elmt); end loop; end Cleanup_Scopes; ------------------------- -- Expand_Inlined_Call -- ------------------------- procedure Expand_Inlined_Call (N : Node_Id; Subp : Entity_Id; Orig_Subp : Entity_Id) is Loc : constant Source_Ptr := Sloc (N); Is_Predef : constant Boolean := Is_Predefined_Unit (Get_Source_Unit (Subp)); Orig_Bod : constant Node_Id := Body_To_Inline (Unit_Declaration_Node (Subp)); Blk : Node_Id; Decl : Node_Id; Decls : constant List_Id := New_List; Exit_Lab : Entity_Id := Empty; F : Entity_Id; A : Node_Id; Lab_Decl : Node_Id := Empty; Lab_Id : Node_Id; New_A : Node_Id; Num_Ret : Nat := 0; Ret_Type : Entity_Id; Targ : Node_Id := Empty; -- The target of the call. If context is an assignment statement then -- this is the left-hand side of the assignment, else it is a temporary -- to which the return value is assigned prior to rewriting the call. Targ1 : Node_Id := Empty; -- A separate target used when the return type is unconstrained Temp : Entity_Id; Temp_Typ : Entity_Id; Return_Object : Entity_Id := Empty; -- Entity in declaration in an extended_return_statement Is_Unc : Boolean; Is_Unc_Decl : Boolean; -- If the type returned by the function is unconstrained and the call -- can be inlined, special processing is required. procedure Declare_Postconditions_Result; -- When generating C code, declare _Result, which may be used in the -- inlined _Postconditions procedure to verify the return value. procedure Make_Exit_Label; -- Build declaration for exit label to be used in Return statements, -- sets Exit_Lab (the label node) and Lab_Decl (corresponding implicit -- declaration). Does nothing if Exit_Lab already set. function Process_Formals (N : Node_Id) return Traverse_Result; -- Replace occurrence of a formal with the corresponding actual, or the -- thunk generated for it. Replace a return statement with an assignment -- to the target of the call, with appropriate conversions if needed. function Process_Sloc (Nod : Node_Id) return Traverse_Result; -- If the call being expanded is that of an internal subprogram, set the -- sloc of the generated block to that of the call itself, so that the -- expansion is skipped by the "next" command in gdb. Same processing -- for a subprogram in a predefined file, e.g. Ada.Tags. If -- Debug_Generated_Code is true, suppress this change to simplify our -- own development. Same in GNATprove mode, to ensure that warnings and -- diagnostics point to the proper location. procedure Reset_Dispatching_Calls (N : Node_Id); -- In subtree N search for occurrences of dispatching calls that use the -- Ada 2005 Object.Operation notation and the object is a formal of the -- inlined subprogram. Reset the entity associated with Operation in all -- the found occurrences. procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id); -- If the function body is a single expression, replace call with -- expression, else insert block appropriately. procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id); -- If procedure body has no local variables, inline body without -- creating block, otherwise rewrite call with block. function Formal_Is_Used_Once (Formal : Entity_Id) return Boolean; -- Determine whether a formal parameter is used only once in Orig_Bod ----------------------------------- -- Declare_Postconditions_Result -- ----------------------------------- procedure Declare_Postconditions_Result is Enclosing_Subp : constant Entity_Id := Scope (Subp); begin pragma Assert (Modify_Tree_For_C and then Is_Subprogram (Enclosing_Subp) and then Present (Postconditions_Proc (Enclosing_Subp))); if Ekind (Enclosing_Subp) = E_Function then if Nkind (First (Parameter_Associations (N))) in N_Numeric_Or_String_Literal then Append_To (Declarations (Blk), Make_Object_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uResult), Constant_Present => True, Object_Definition => New_Occurrence_Of (Etype (Enclosing_Subp), Loc), Expression => New_Copy_Tree (First (Parameter_Associations (N))))); else Append_To (Declarations (Blk), Make_Object_Renaming_Declaration (Loc, Defining_Identifier => Make_Defining_Identifier (Loc, Name_uResult), Subtype_Mark => New_Occurrence_Of (Etype (Enclosing_Subp), Loc), Name => New_Copy_Tree (First (Parameter_Associations (N))))); end if; end if; end Declare_Postconditions_Result; --------------------- -- Make_Exit_Label -- --------------------- procedure Make_Exit_Label is Lab_Ent : Entity_Id; begin if No (Exit_Lab) then Lab_Ent := Make_Temporary (Loc, 'L'); Lab_Id := New_Occurrence_Of (Lab_Ent, Loc); Exit_Lab := Make_Label (Loc, Lab_Id); Lab_Decl := Make_Implicit_Label_Declaration (Loc, Defining_Identifier => Lab_Ent, Label_Construct => Exit_Lab); end if; end Make_Exit_Label; --------------------- -- Process_Formals -- --------------------- function Process_Formals (N : Node_Id) return Traverse_Result is A : Entity_Id; E : Entity_Id; Ret : Node_Id; begin if Is_Entity_Name (N) and then Present (Entity (N)) then E := Entity (N); if Is_Formal (E) and then Scope (E) = Subp then A := Renamed_Object (E); -- Rewrite the occurrence of the formal into an occurrence of -- the actual. Also establish visibility on the proper view of -- the actual's subtype for the body's context (if the actual's -- subtype is private at the call point but its full view is -- visible to the body, then the inlined tree here must be -- analyzed with the full view). if Is_Entity_Name (A) then Rewrite (N, New_Occurrence_Of (Entity (A), Sloc (N))); Check_Private_View (N); elsif Nkind (A) = N_Defining_Identifier then Rewrite (N, New_Occurrence_Of (A, Sloc (N))); Check_Private_View (N); -- Numeric literal else Rewrite (N, New_Copy (A)); end if; end if; return Skip; elsif Is_Entity_Name (N) and then Present (Return_Object) and then Chars (N) = Chars (Return_Object) then -- Occurrence within an extended return statement. The return -- object is local to the body been inlined, and thus the generic -- copy is not analyzed yet, so we match by name, and replace it -- with target of call. if Nkind (Targ) = N_Defining_Identifier then Rewrite (N, New_Occurrence_Of (Targ, Loc)); else Rewrite (N, New_Copy_Tree (Targ)); end if; return Skip; elsif Nkind (N) = N_Simple_Return_Statement then if No (Expression (N)) then Num_Ret := Num_Ret + 1; Make_Exit_Label; Rewrite (N, Make_Goto_Statement (Loc, Name => New_Copy (Lab_Id))); else if Nkind (Parent (N)) = N_Handled_Sequence_Of_Statements and then Nkind (Parent (Parent (N))) = N_Subprogram_Body then -- Function body is a single expression. No need for -- exit label. null; else Num_Ret := Num_Ret + 1; Make_Exit_Label; end if; -- Because of the presence of private types, the views of the -- expression and the context may be different, so place an -- unchecked conversion to the context type to avoid spurious -- errors, e.g. when the expression is a numeric literal and -- the context is private. If the expression is an aggregate, -- use a qualified expression, because an aggregate is not a -- legal argument of a conversion. Ditto for numeric literals -- and attributes that yield a universal type, because those -- must be resolved to a specific type. if Nkind_In (Expression (N), N_Aggregate, N_Null) or else Yields_Universal_Type (Expression (N)) then Ret := Make_Qualified_Expression (Sloc (N), Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)), Expression => Relocate_Node (Expression (N))); else Ret := Unchecked_Convert_To (Ret_Type, Relocate_Node (Expression (N))); end if; if Nkind (Targ) = N_Defining_Identifier then Rewrite (N, Make_Assignment_Statement (Loc, Name => New_Occurrence_Of (Targ, Loc), Expression => Ret)); else Rewrite (N, Make_Assignment_Statement (Loc, Name => New_Copy (Targ), Expression => Ret)); end if; Set_Assignment_OK (Name (N)); if Present (Exit_Lab) then Insert_After (N, Make_Goto_Statement (Loc, Name => New_Copy (Lab_Id))); end if; end if; return OK; -- An extended return becomes a block whose first statement is the -- assignment of the initial expression of the return object to the -- target of the call itself. elsif Nkind (N) = N_Extended_Return_Statement then declare Return_Decl : constant Entity_Id := First (Return_Object_Declarations (N)); Assign : Node_Id; begin Return_Object := Defining_Identifier (Return_Decl); if Present (Expression (Return_Decl)) then if Nkind (Targ) = N_Defining_Identifier then Assign := Make_Assignment_Statement (Loc, Name => New_Occurrence_Of (Targ, Loc), Expression => Expression (Return_Decl)); else Assign := Make_Assignment_Statement (Loc, Name => New_Copy (Targ), Expression => Expression (Return_Decl)); end if; Set_Assignment_OK (Name (Assign)); if No (Handled_Statement_Sequence (N)) then Set_Handled_Statement_Sequence (N, Make_Handled_Sequence_Of_Statements (Loc, Statements => New_List)); end if; Prepend (Assign, Statements (Handled_Statement_Sequence (N))); end if; Rewrite (N, Make_Block_Statement (Loc, Handled_Statement_Sequence => Handled_Statement_Sequence (N))); return OK; end; -- Remove pragma Unreferenced since it may refer to formals that -- are not visible in the inlined body, and in any case we will -- not be posting warnings on the inlined body so it is unneeded. elsif Nkind (N) = N_Pragma and then Pragma_Name (N) = Name_Unreferenced then Rewrite (N, Make_Null_Statement (Sloc (N))); return OK; else return OK; end if; end Process_Formals; procedure Replace_Formals is new Traverse_Proc (Process_Formals); ------------------ -- Process_Sloc -- ------------------ function Process_Sloc (Nod : Node_Id) return Traverse_Result is begin if not Debug_Generated_Code then Set_Sloc (Nod, Sloc (N)); Set_Comes_From_Source (Nod, False); end if; return OK; end Process_Sloc; procedure Reset_Slocs is new Traverse_Proc (Process_Sloc); ------------------------------ -- Reset_Dispatching_Calls -- ------------------------------ procedure Reset_Dispatching_Calls (N : Node_Id) is function Do_Reset (N : Node_Id) return Traverse_Result; -- Comment required ??? -------------- -- Do_Reset -- -------------- function Do_Reset (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Procedure_Call_Statement and then Nkind (Name (N)) = N_Selected_Component and then Nkind (Prefix (Name (N))) = N_Identifier and then Is_Formal (Entity (Prefix (Name (N)))) and then Is_Dispatching_Operation (Entity (Selector_Name (Name (N)))) then Set_Entity (Selector_Name (Name (N)), Empty); end if; return OK; end Do_Reset; function Do_Reset_Calls is new Traverse_Func (Do_Reset); -- Local variables Dummy : constant Traverse_Result := Do_Reset_Calls (N); pragma Unreferenced (Dummy); -- Start of processing for Reset_Dispatching_Calls begin null; end Reset_Dispatching_Calls; --------------------------- -- Rewrite_Function_Call -- --------------------------- procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id) is HSS : constant Node_Id := Handled_Statement_Sequence (Blk); Fst : constant Node_Id := First (Statements (HSS)); begin -- Optimize simple case: function body is a single return statement, -- which has been expanded into an assignment. if Is_Empty_List (Declarations (Blk)) and then Nkind (Fst) = N_Assignment_Statement and then No (Next (Fst)) then -- The function call may have been rewritten as the temporary -- that holds the result of the call, in which case remove the -- now useless declaration. if Nkind (N) = N_Identifier and then Nkind (Parent (Entity (N))) = N_Object_Declaration then Rewrite (Parent (Entity (N)), Make_Null_Statement (Loc)); end if; Rewrite (N, Expression (Fst)); elsif Nkind (N) = N_Identifier and then Nkind (Parent (Entity (N))) = N_Object_Declaration then -- The block assigns the result of the call to the temporary Insert_After (Parent (Entity (N)), Blk); -- If the context is an assignment, and the left-hand side is free of -- side-effects, the replacement is also safe. -- Can this be generalized further??? elsif Nkind (Parent (N)) = N_Assignment_Statement and then (Is_Entity_Name (Name (Parent (N))) or else (Nkind (Name (Parent (N))) = N_Explicit_Dereference and then Is_Entity_Name (Prefix (Name (Parent (N))))) or else (Nkind (Name (Parent (N))) = N_Selected_Component and then Is_Entity_Name (Prefix (Name (Parent (N)))))) then -- Replace assignment with the block declare Original_Assignment : constant Node_Id := Parent (N); begin -- Preserve the original assignment node to keep the complete -- assignment subtree consistent enough for Analyze_Assignment -- to proceed (specifically, the original Lhs node must still -- have an assignment statement as its parent). -- We cannot rely on Original_Node to go back from the block -- node to the assignment node, because the assignment might -- already be a rewrite substitution. Discard_Node (Relocate_Node (Original_Assignment)); Rewrite (Original_Assignment, Blk); end; elsif Nkind (Parent (N)) = N_Object_Declaration then -- A call to a function which returns an unconstrained type -- found in the expression initializing an object-declaration is -- expanded into a procedure call which must be added after the -- object declaration. if Is_Unc_Decl and Back_End_Inlining then Insert_Action_After (Parent (N), Blk); else Set_Expression (Parent (N), Empty); Insert_After (Parent (N), Blk); end if; elsif Is_Unc and then not Back_End_Inlining then Insert_Before (Parent (N), Blk); end if; end Rewrite_Function_Call; ---------------------------- -- Rewrite_Procedure_Call -- ---------------------------- procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id) is HSS : constant Node_Id := Handled_Statement_Sequence (Blk); begin -- If there is a transient scope for N, this will be the scope of the -- actions for N, and the statements in Blk need to be within this -- scope. For example, they need to have visibility on the constant -- declarations created for the formals. -- If N needs no transient scope, and if there are no declarations in -- the inlined body, we can do a little optimization and insert the -- statements for the body directly after N, and rewrite N to a -- null statement, instead of rewriting N into a full-blown block -- statement. if not Scope_Is_Transient and then Is_Empty_List (Declarations (Blk)) then Insert_List_After (N, Statements (HSS)); Rewrite (N, Make_Null_Statement (Loc)); else Rewrite (N, Blk); end if; end Rewrite_Procedure_Call; ------------------------- -- Formal_Is_Used_Once -- ------------------------- function Formal_Is_Used_Once (Formal : Entity_Id) return Boolean is Use_Counter : Int := 0; function Count_Uses (N : Node_Id) return Traverse_Result; -- Traverse the tree and count the uses of the formal parameter. -- In this case, for optimization purposes, we do not need to -- continue the traversal once more than one use is encountered. ---------------- -- Count_Uses -- ---------------- function Count_Uses (N : Node_Id) return Traverse_Result is begin -- The original node is an identifier if Nkind (N) = N_Identifier and then Present (Entity (N)) -- Original node's entity points to the one in the copied body and then Nkind (Entity (N)) = N_Identifier and then Present (Entity (Entity (N))) -- The entity of the copied node is the formal parameter and then Entity (Entity (N)) = Formal then Use_Counter := Use_Counter + 1; if Use_Counter > 1 then -- Denote more than one use and abandon the traversal Use_Counter := 2; return Abandon; end if; end if; return OK; end Count_Uses; procedure Count_Formal_Uses is new Traverse_Proc (Count_Uses); -- Start of processing for Formal_Is_Used_Once begin Count_Formal_Uses (Orig_Bod); return Use_Counter = 1; end Formal_Is_Used_Once; -- Start of processing for Expand_Inlined_Call begin -- Initializations for old/new semantics if not Back_End_Inlining then Is_Unc := Is_Array_Type (Etype (Subp)) and then not Is_Constrained (Etype (Subp)); Is_Unc_Decl := False; else Is_Unc := Returns_Unconstrained_Type (Subp) and then Optimization_Level > 0; Is_Unc_Decl := Nkind (Parent (N)) = N_Object_Declaration and then Is_Unc; end if; -- Check for an illegal attempt to inline a recursive procedure. If the -- subprogram has parameters this is detected when trying to supply a -- binding for parameters that already have one. For parameterless -- subprograms this must be done explicitly. if In_Open_Scopes (Subp) then Cannot_Inline ("cannot inline call to recursive subprogram?", N, Subp); Set_Is_Inlined (Subp, False); return; -- Skip inlining if this is not a true inlining since the attribute -- Body_To_Inline is also set for renamings (see sinfo.ads). For a -- true inlining, Orig_Bod has code rather than being an entity. elsif Nkind (Orig_Bod) in N_Entity then return; -- Skip inlining if the function returns an unconstrained type using -- an extended return statement since this part of the new inlining -- model which is not yet supported by the current implementation. ??? elsif Is_Unc and then Nkind (First (Statements (Handled_Statement_Sequence (Orig_Bod)))) = N_Extended_Return_Statement and then not Back_End_Inlining then return; end if; if Nkind (Orig_Bod) = N_Defining_Identifier or else Nkind (Orig_Bod) = N_Defining_Operator_Symbol then -- Subprogram is renaming_as_body. Calls occurring after the renaming -- can be replaced with calls to the renamed entity directly, because -- the subprograms are subtype conformant. If the renamed subprogram -- is an inherited operation, we must redo the expansion because -- implicit conversions may be needed. Similarly, if the renamed -- entity is inlined, expand the call for further optimizations. Set_Name (N, New_Occurrence_Of (Orig_Bod, Loc)); if Present (Alias (Orig_Bod)) or else Is_Inlined (Orig_Bod) then Expand_Call (N); end if; return; end if; -- Register the call in the list of inlined calls Append_New_Elmt (N, To => Inlined_Calls); -- Use generic machinery to copy body of inlined subprogram, as if it -- were an instantiation, resetting source locations appropriately, so -- that nested inlined calls appear in the main unit. Save_Env (Subp, Empty); Set_Copied_Sloc_For_Inlined_Body (N, Defining_Entity (Orig_Bod)); -- Old semantics if not Back_End_Inlining then declare Bod : Node_Id; begin Bod := Copy_Generic_Node (Orig_Bod, Empty, Instantiating => True); Blk := Make_Block_Statement (Loc, Declarations => Declarations (Bod), Handled_Statement_Sequence => Handled_Statement_Sequence (Bod)); if No (Declarations (Bod)) then Set_Declarations (Blk, New_List); end if; -- When generating C code, declare _Result, which may be used to -- verify the return value. if Modify_Tree_For_C and then Nkind (N) = N_Procedure_Call_Statement and then Chars (Name (N)) = Name_uPostconditions then Declare_Postconditions_Result; end if; -- For the unconstrained case, capture the name of the local -- variable that holds the result. This must be the first -- declaration in the block, because its bounds cannot depend -- on local variables. Otherwise there is no way to declare the -- result outside of the block. Needless to say, in general the -- bounds will depend on the actuals in the call. -- If the context is an assignment statement, as is the case -- for the expansion of an extended return, the left-hand side -- provides bounds even if the return type is unconstrained. if Is_Unc then declare First_Decl : Node_Id; begin First_Decl := First (Declarations (Blk)); if Nkind (First_Decl) /= N_Object_Declaration then return; end if; if Nkind (Parent (N)) /= N_Assignment_Statement then Targ1 := Defining_Identifier (First_Decl); else Targ1 := Name (Parent (N)); end if; end; end if; end; -- New semantics else declare Bod : Node_Id; begin -- General case if not Is_Unc then Bod := Copy_Generic_Node (Orig_Bod, Empty, Instantiating => True); Blk := Make_Block_Statement (Loc, Declarations => Declarations (Bod), Handled_Statement_Sequence => Handled_Statement_Sequence (Bod)); -- Inline a call to a function that returns an unconstrained type. -- The semantic analyzer checked that frontend-inlined functions -- returning unconstrained types have no declarations and have -- a single extended return statement. As part of its processing -- the function was split into two subprograms: a procedure P' and -- a function F' that has a block with a call to procedure P' (see -- Split_Unconstrained_Function). else pragma Assert (Nkind (First (Statements (Handled_Statement_Sequence (Orig_Bod)))) = N_Block_Statement); declare Blk_Stmt : constant Node_Id := First (Statements (Handled_Statement_Sequence (Orig_Bod))); First_Stmt : constant Node_Id := First (Statements (Handled_Statement_Sequence (Blk_Stmt))); Second_Stmt : constant Node_Id := Next (First_Stmt); begin pragma Assert (Nkind (First_Stmt) = N_Procedure_Call_Statement and then Nkind (Second_Stmt) = N_Simple_Return_Statement and then No (Next (Second_Stmt))); Bod := Copy_Generic_Node (First (Statements (Handled_Statement_Sequence (Orig_Bod))), Empty, Instantiating => True); Blk := Bod; -- Capture the name of the local variable that holds the -- result. This must be the first declaration in the block, -- because its bounds cannot depend on local variables. -- Otherwise there is no way to declare the result outside -- of the block. Needless to say, in general the bounds will -- depend on the actuals in the call. if Nkind (Parent (N)) /= N_Assignment_Statement then Targ1 := Defining_Identifier (First (Declarations (Blk))); -- If the context is an assignment statement, as is the case -- for the expansion of an extended return, the left-hand -- side provides bounds even if the return type is -- unconstrained. else Targ1 := Name (Parent (N)); end if; end; end if; if No (Declarations (Bod)) then Set_Declarations (Blk, New_List); end if; end; end if; -- If this is a derived function, establish the proper return type if Present (Orig_Subp) and then Orig_Subp /= Subp then Ret_Type := Etype (Orig_Subp); else Ret_Type := Etype (Subp); end if; -- Create temporaries for the actuals that are expressions, or that are -- scalars and require copying to preserve semantics. F := First_Formal (Subp); A := First_Actual (N); while Present (F) loop if Present (Renamed_Object (F)) then -- If expander is active, it is an error to try to inline a -- recursive program. In GNATprove mode, just indicate that the -- inlining will not happen, and mark the subprogram as not always -- inlined. if GNATprove_Mode then Cannot_Inline ("cannot inline call to recursive subprogram?", N, Subp); Set_Is_Inlined_Always (Subp, False); else Error_Msg_N ("cannot inline call to recursive subprogram", N); end if; return; end if; -- Reset Last_Assignment for any parameters of mode out or in out, to -- prevent spurious warnings about overwriting for assignments to the -- formal in the inlined code. if Is_Entity_Name (A) and then Ekind (F) /= E_In_Parameter then Set_Last_Assignment (Entity (A), Empty); end if; -- If the argument may be a controlling argument in a call within -- the inlined body, we must preserve its classwide nature to insure -- that dynamic dispatching take place subsequently. If the formal -- has a constraint it must be preserved to retain the semantics of -- the body. if Is_Class_Wide_Type (Etype (F)) or else (Is_Access_Type (Etype (F)) and then Is_Class_Wide_Type (Designated_Type (Etype (F)))) then Temp_Typ := Etype (F); elsif Base_Type (Etype (F)) = Base_Type (Etype (A)) and then Etype (F) /= Base_Type (Etype (F)) and then Is_Constrained (Etype (F)) then Temp_Typ := Etype (F); else Temp_Typ := Etype (A); end if; -- If the actual is a simple name or a literal, no need to -- create a temporary, object can be used directly. -- If the actual is a literal and the formal has its address taken, -- we cannot pass the literal itself as an argument, so its value -- must be captured in a temporary. Skip this optimization in -- GNATprove mode, to make sure any check on a type conversion -- will be issued. if (Is_Entity_Name (A) and then (not Is_Scalar_Type (Etype (A)) or else Ekind (Entity (A)) = E_Enumeration_Literal) and then not GNATprove_Mode) -- When the actual is an identifier and the corresponding formal is -- used only once in the original body, the formal can be substituted -- directly with the actual parameter. Skip this optimization in -- GNATprove mode, to make sure any check on a type conversion -- will be issued. or else (Nkind (A) = N_Identifier and then Formal_Is_Used_Once (F) and then not GNATprove_Mode) or else (Nkind_In (A, N_Real_Literal, N_Integer_Literal, N_Character_Literal) and then not Address_Taken (F)) then if Etype (F) /= Etype (A) then Set_Renamed_Object (F, Unchecked_Convert_To (Etype (F), Relocate_Node (A))); else Set_Renamed_Object (F, A); end if; else Temp := Make_Temporary (Loc, 'C'); -- If the actual for an in/in-out parameter is a view conversion, -- make it into an unchecked conversion, given that an untagged -- type conversion is not a proper object for a renaming. -- In-out conversions that involve real conversions have already -- been transformed in Expand_Actuals. if Nkind (A) = N_Type_Conversion and then Ekind (F) /= E_In_Parameter then New_A := Make_Unchecked_Type_Conversion (Loc, Subtype_Mark => New_Occurrence_Of (Etype (F), Loc), Expression => Relocate_Node (Expression (A))); -- In GNATprove mode, keep the most precise type of the actual for -- the temporary variable, when the formal type is unconstrained. -- Otherwise, the AST may contain unexpected assignment statements -- to a temporary variable of unconstrained type renaming a local -- variable of constrained type, which is not expected by -- GNATprove. elsif Etype (F) /= Etype (A) and then (not GNATprove_Mode or else Is_Constrained (Etype (F))) then New_A := Unchecked_Convert_To (Etype (F), Relocate_Node (A)); Temp_Typ := Etype (F); else New_A := Relocate_Node (A); end if; Set_Sloc (New_A, Sloc (N)); -- If the actual has a by-reference type, it cannot be copied, -- so its value is captured in a renaming declaration. Otherwise -- declare a local constant initialized with the actual. -- We also use a renaming declaration for expressions of an array -- type that is not bit-packed, both for efficiency reasons and to -- respect the semantics of the call: in most cases the original -- call will pass the parameter by reference, and thus the inlined -- code will have the same semantics. -- Finally, we need a renaming declaration in the case of limited -- types for which initialization cannot be by copy either. if Ekind (F) = E_In_Parameter and then not Is_By_Reference_Type (Etype (A)) and then not Is_Limited_Type (Etype (A)) and then (not Is_Array_Type (Etype (A)) or else not Is_Object_Reference (A) or else Is_Bit_Packed_Array (Etype (A))) then Decl := Make_Object_Declaration (Loc, Defining_Identifier => Temp, Constant_Present => True, Object_Definition => New_Occurrence_Of (Temp_Typ, Loc), Expression => New_A); else -- In GNATprove mode, make an explicit copy of input -- parameters when formal and actual types differ, to make -- sure any check on the type conversion will be issued. -- The legality of the copy is ensured by calling first -- Call_Can_Be_Inlined_In_GNATprove_Mode. if GNATprove_Mode and then Ekind (F) /= E_Out_Parameter and then not Same_Type (Etype (F), Etype (A)) then pragma Assert (not (Is_By_Reference_Type (Etype (A)))); pragma Assert (not (Is_Limited_Type (Etype (A)))); Append_To (Decls, Make_Object_Declaration (Loc, Defining_Identifier => Make_Temporary (Loc, 'C'), Constant_Present => True, Object_Definition => New_Occurrence_Of (Temp_Typ, Loc), Expression => New_Copy_Tree (New_A))); end if; Decl := Make_Object_Renaming_Declaration (Loc, Defining_Identifier => Temp, Subtype_Mark => New_Occurrence_Of (Temp_Typ, Loc), Name => New_A); end if; Append (Decl, Decls); Set_Renamed_Object (F, Temp); end if; Next_Formal (F); Next_Actual (A); end loop; -- Establish target of function call. If context is not assignment or -- declaration, create a temporary as a target. The declaration for the -- temporary may be subsequently optimized away if the body is a single -- expression, or if the left-hand side of the assignment is simple -- enough, i.e. an entity or an explicit dereference of one. if Ekind (Subp) = E_Function then if Nkind (Parent (N)) = N_Assignment_Statement and then Is_Entity_Name (Name (Parent (N))) then Targ := Name (Parent (N)); elsif Nkind (Parent (N)) = N_Assignment_Statement and then Nkind (Name (Parent (N))) = N_Explicit_Dereference and then Is_Entity_Name (Prefix (Name (Parent (N)))) then Targ := Name (Parent (N)); elsif Nkind (Parent (N)) = N_Assignment_Statement and then Nkind (Name (Parent (N))) = N_Selected_Component and then Is_Entity_Name (Prefix (Name (Parent (N)))) then Targ := New_Copy_Tree (Name (Parent (N))); elsif Nkind (Parent (N)) = N_Object_Declaration and then Is_Limited_Type (Etype (Subp)) then Targ := Defining_Identifier (Parent (N)); -- New semantics: In an object declaration avoid an extra copy -- of the result of a call to an inlined function that returns -- an unconstrained type elsif Back_End_Inlining and then Nkind (Parent (N)) = N_Object_Declaration and then Is_Unc then Targ := Defining_Identifier (Parent (N)); else -- Replace call with temporary and create its declaration Temp := Make_Temporary (Loc, 'C'); Set_Is_Internal (Temp); -- For the unconstrained case, the generated temporary has the -- same constrained declaration as the result variable. It may -- eventually be possible to remove that temporary and use the -- result variable directly. if Is_Unc and then Nkind (Parent (N)) /= N_Assignment_Statement then Decl := Make_Object_Declaration (Loc, Defining_Identifier => Temp, Object_Definition => New_Copy_Tree (Object_Definition (Parent (Targ1)))); Replace_Formals (Decl); else Decl := Make_Object_Declaration (Loc, Defining_Identifier => Temp, Object_Definition => New_Occurrence_Of (Ret_Type, Loc)); Set_Etype (Temp, Ret_Type); end if; Set_No_Initialization (Decl); Append (Decl, Decls); Rewrite (N, New_Occurrence_Of (Temp, Loc)); Targ := Temp; end if; end if; Insert_Actions (N, Decls); if Is_Unc_Decl then -- Special management for inlining a call to a function that returns -- an unconstrained type and initializes an object declaration: we -- avoid generating undesired extra calls and goto statements. -- Given: -- function Func (...) return String is -- begin -- declare -- Result : String (1 .. 4); -- begin -- Proc (Result, ...); -- return Result; -- end; -- end Func; -- Result : String := Func (...); -- Replace this object declaration by: -- Result : String (1 .. 4); -- Proc (Result, ...); Remove_Homonym (Targ); Decl := Make_Object_Declaration (Loc, Defining_Identifier => Targ, Object_Definition => New_Copy_Tree (Object_Definition (Parent (Targ1)))); Replace_Formals (Decl); Rewrite (Parent (N), Decl); Analyze (Parent (N)); -- Avoid spurious warnings since we know that this declaration is -- referenced by the procedure call. Set_Never_Set_In_Source (Targ, False); -- Remove the local declaration of the extended return stmt from the -- inlined code Remove (Parent (Targ1)); -- Update the reference to the result (since we have rewriten the -- object declaration) declare Blk_Call_Stmt : Node_Id; begin -- Capture the call to the procedure Blk_Call_Stmt := First (Statements (Handled_Statement_Sequence (Blk))); pragma Assert (Nkind (Blk_Call_Stmt) = N_Procedure_Call_Statement); Remove (First (Parameter_Associations (Blk_Call_Stmt))); Prepend_To (Parameter_Associations (Blk_Call_Stmt), New_Occurrence_Of (Targ, Loc)); end; -- Remove the return statement pragma Assert (Nkind (Last (Statements (Handled_Statement_Sequence (Blk)))) = N_Simple_Return_Statement); Remove (Last (Statements (Handled_Statement_Sequence (Blk)))); end if; -- Traverse the tree and replace formals with actuals or their thunks. -- Attach block to tree before analysis and rewriting. Replace_Formals (Blk); Set_Parent (Blk, N); if GNATprove_Mode then null; elsif not Comes_From_Source (Subp) or else Is_Predef then Reset_Slocs (Blk); end if; if Is_Unc_Decl then -- No action needed since return statement has been already removed null; elsif Present (Exit_Lab) then -- If there's a single return statement at the end of the subprogram, -- the corresponding goto statement and the corresponding label are -- useless. if Num_Ret = 1 and then Nkind (Last (Statements (Handled_Statement_Sequence (Blk)))) = N_Goto_Statement then Remove (Last (Statements (Handled_Statement_Sequence (Blk)))); else Append (Lab_Decl, (Declarations (Blk))); Append (Exit_Lab, Statements (Handled_Statement_Sequence (Blk))); end if; end if; -- Analyze Blk with In_Inlined_Body set, to avoid spurious errors -- on conflicting private views that Gigi would ignore. If this is a -- predefined unit, analyze with checks off, as is done in the non- -- inlined run-time units. declare I_Flag : constant Boolean := In_Inlined_Body; begin In_Inlined_Body := True; if Is_Predef then declare Style : constant Boolean := Style_Check; begin Style_Check := False; -- Search for dispatching calls that use the Object.Operation -- notation using an Object that is a parameter of the inlined -- function. We reset the decoration of Operation to force -- the reanalysis of the inlined dispatching call because -- the actual object has been inlined. Reset_Dispatching_Calls (Blk); Analyze (Blk, Suppress => All_Checks); Style_Check := Style; end; else Analyze (Blk); end if; In_Inlined_Body := I_Flag; end; if Ekind (Subp) = E_Procedure then Rewrite_Procedure_Call (N, Blk); else Rewrite_Function_Call (N, Blk); if Is_Unc_Decl then null; -- For the unconstrained case, the replacement of the call has been -- made prior to the complete analysis of the generated declarations. -- Propagate the proper type now. elsif Is_Unc then if Nkind (N) = N_Identifier then Set_Etype (N, Etype (Entity (N))); else Set_Etype (N, Etype (Targ1)); end if; end if; end if; Restore_Env; -- Cleanup mapping between formals and actuals for other expansions F := First_Formal (Subp); while Present (F) loop Set_Renamed_Object (F, Empty); Next_Formal (F); end loop; end Expand_Inlined_Call; -------------------------- -- Get_Code_Unit_Entity -- -------------------------- function Get_Code_Unit_Entity (E : Entity_Id) return Entity_Id is Unit : Entity_Id := Cunit_Entity (Get_Code_Unit (E)); begin if Ekind (Unit) = E_Package_Body then Unit := Spec_Entity (Unit); end if; return Unit; end Get_Code_Unit_Entity; ------------------------------ -- Has_Excluded_Declaration -- ------------------------------ function Has_Excluded_Declaration (Subp : Entity_Id; Decls : List_Id) return Boolean is D : Node_Id; function Is_Unchecked_Conversion (D : Node_Id) return Boolean; -- Nested subprograms make a given body ineligible for inlining, but -- we make an exception for instantiations of unchecked conversion. -- The body has not been analyzed yet, so check the name, and verify -- that the visible entity with that name is the predefined unit. ----------------------------- -- Is_Unchecked_Conversion -- ----------------------------- function Is_Unchecked_Conversion (D : Node_Id) return Boolean is Id : constant Node_Id := Name (D); Conv : Entity_Id; begin if Nkind (Id) = N_Identifier and then Chars (Id) = Name_Unchecked_Conversion then Conv := Current_Entity (Id); elsif Nkind_In (Id, N_Selected_Component, N_Expanded_Name) and then Chars (Selector_Name (Id)) = Name_Unchecked_Conversion then Conv := Current_Entity (Selector_Name (Id)); else return False; end if; return Present (Conv) and then Is_Predefined_Unit (Get_Source_Unit (Conv)) and then Is_Intrinsic_Subprogram (Conv); end Is_Unchecked_Conversion; -- Start of processing for Has_Excluded_Declaration begin -- No action needed if the check is not needed if not Check_Inlining_Restrictions then return False; end if; D := First (Decls); while Present (D) loop -- First declarations universally excluded if Nkind (D) = N_Package_Declaration then Cannot_Inline ("cannot inline & (nested package declaration)?", D, Subp); return True; elsif Nkind (D) = N_Package_Instantiation then Cannot_Inline ("cannot inline & (nested package instantiation)?", D, Subp); return True; end if; -- Then declarations excluded only for front-end inlining if Back_End_Inlining then null; elsif Nkind (D) = N_Task_Type_Declaration or else Nkind (D) = N_Single_Task_Declaration then Cannot_Inline ("cannot inline & (nested task type declaration)?", D, Subp); return True; elsif Nkind (D) = N_Protected_Type_Declaration or else Nkind (D) = N_Single_Protected_Declaration then Cannot_Inline ("cannot inline & (nested protected type declaration)?", D, Subp); return True; elsif Nkind (D) = N_Subprogram_Body then Cannot_Inline ("cannot inline & (nested subprogram)?", D, Subp); return True; elsif Nkind (D) = N_Function_Instantiation and then not Is_Unchecked_Conversion (D) then Cannot_Inline ("cannot inline & (nested function instantiation)?", D, Subp); return True; elsif Nkind (D) = N_Procedure_Instantiation then Cannot_Inline ("cannot inline & (nested procedure instantiation)?", D, Subp); return True; -- Subtype declarations with predicates will generate predicate -- functions, i.e. nested subprogram bodies, so inlining is not -- possible. elsif Nkind (D) = N_Subtype_Declaration and then Present (Aspect_Specifications (D)) then declare A : Node_Id; A_Id : Aspect_Id; begin A := First (Aspect_Specifications (D)); while Present (A) loop A_Id := Get_Aspect_Id (Chars (Identifier (A))); if A_Id = Aspect_Predicate or else A_Id = Aspect_Static_Predicate or else A_Id = Aspect_Dynamic_Predicate then Cannot_Inline ("cannot inline & (subtype declaration with " & "predicate)?", D, Subp); return True; end if; Next (A); end loop; end; end if; Next (D); end loop; return False; end Has_Excluded_Declaration; ---------------------------- -- Has_Excluded_Statement -- ---------------------------- function Has_Excluded_Statement (Subp : Entity_Id; Stats : List_Id) return Boolean is S : Node_Id; E : Node_Id; begin -- No action needed if the check is not needed if not Check_Inlining_Restrictions then return False; end if; S := First (Stats); while Present (S) loop if Nkind_In (S, N_Abort_Statement, N_Asynchronous_Select, N_Conditional_Entry_Call, N_Delay_Relative_Statement, N_Delay_Until_Statement, N_Selective_Accept, N_Timed_Entry_Call) then Cannot_Inline ("cannot inline & (non-allowed statement)?", S, Subp); return True; elsif Nkind (S) = N_Block_Statement then if Present (Declarations (S)) and then Has_Excluded_Declaration (Subp, Declarations (S)) then return True; elsif Present (Handled_Statement_Sequence (S)) then if not Back_End_Inlining and then Present (Exception_Handlers (Handled_Statement_Sequence (S))) then Cannot_Inline ("cannot inline& (exception handler)?", First (Exception_Handlers (Handled_Statement_Sequence (S))), Subp); return True; elsif Has_Excluded_Statement (Subp, Statements (Handled_Statement_Sequence (S))) then return True; end if; end if; elsif Nkind (S) = N_Case_Statement then E := First (Alternatives (S)); while Present (E) loop if Has_Excluded_Statement (Subp, Statements (E)) then return True; end if; Next (E); end loop; elsif Nkind (S) = N_If_Statement then if Has_Excluded_Statement (Subp, Then_Statements (S)) then return True; end if; if Present (Elsif_Parts (S)) then E := First (Elsif_Parts (S)); while Present (E) loop if Has_Excluded_Statement (Subp, Then_Statements (E)) then return True; end if; Next (E); end loop; end if; if Present (Else_Statements (S)) and then Has_Excluded_Statement (Subp, Else_Statements (S)) then return True; end if; elsif Nkind (S) = N_Loop_Statement and then Has_Excluded_Statement (Subp, Statements (S)) then return True; elsif Nkind (S) = N_Extended_Return_Statement then if Present (Handled_Statement_Sequence (S)) and then Has_Excluded_Statement (Subp, Statements (Handled_Statement_Sequence (S))) then return True; elsif not Back_End_Inlining and then Present (Handled_Statement_Sequence (S)) and then Present (Exception_Handlers (Handled_Statement_Sequence (S))) then Cannot_Inline ("cannot inline& (exception handler)?", First (Exception_Handlers (Handled_Statement_Sequence (S))), Subp); return True; end if; end if; Next (S); end loop; return False; end Has_Excluded_Statement; -------------------------- -- Has_Initialized_Type -- -------------------------- function Has_Initialized_Type (E : Entity_Id) return Boolean is E_Body : constant Node_Id := Subprogram_Body (E); Decl : Node_Id; begin if No (E_Body) then -- imported subprogram return False; else Decl := First (Declarations (E_Body)); while Present (Decl) loop if Nkind (Decl) = N_Full_Type_Declaration and then Present (Init_Proc (Defining_Identifier (Decl))) then return True; end if; Next (Decl); end loop; end if; return False; end Has_Initialized_Type; ----------------------- -- Has_Single_Return -- ----------------------- function Has_Single_Return (N : Node_Id) return Boolean is Return_Statement : Node_Id := Empty; function Check_Return (N : Node_Id) return Traverse_Result; ------------------ -- Check_Return -- ------------------ function Check_Return (N : Node_Id) return Traverse_Result is begin if Nkind (N) = N_Simple_Return_Statement then if Present (Expression (N)) and then Is_Entity_Name (Expression (N)) then if No (Return_Statement) then Return_Statement := N; return OK; elsif Chars (Expression (N)) = Chars (Expression (Return_Statement)) then return OK; else return Abandon; end if; -- A return statement within an extended return is a noop -- after inlining. elsif No (Expression (N)) and then Nkind (Parent (Parent (N))) = N_Extended_Return_Statement then return OK; else -- Expression has wrong form return Abandon; end if; -- We can only inline a build-in-place function if it has a single -- extended return. elsif Nkind (N) = N_Extended_Return_Statement then if No (Return_Statement) then Return_Statement := N; return OK; else return Abandon; end if; else return OK; end if; end Check_Return; function Check_All_Returns is new Traverse_Func (Check_Return); -- Start of processing for Has_Single_Return begin if Check_All_Returns (N) /= OK then return False; elsif Nkind (Return_Statement) = N_Extended_Return_Statement then return True; else return Present (Declarations (N)) and then Present (First (Declarations (N))) and then Chars (Expression (Return_Statement)) = Chars (Defining_Identifier (First (Declarations (N)))); end if; end Has_Single_Return; ----------------------------- -- In_Main_Unit_Or_Subunit -- ----------------------------- function In_Main_Unit_Or_Subunit (E : Entity_Id) return Boolean is Comp : Node_Id := Cunit (Get_Code_Unit (E)); begin -- Check whether the subprogram or package to inline is within the main -- unit or its spec or within a subunit. In either case there are no -- additional bodies to process. If the subprogram appears in a parent -- of the current unit, the check on whether inlining is possible is -- done in Analyze_Inlined_Bodies. while Nkind (Unit (Comp)) = N_Subunit loop Comp := Library_Unit (Comp); end loop; return Comp = Cunit (Main_Unit) or else Comp = Library_Unit (Cunit (Main_Unit)); end In_Main_Unit_Or_Subunit; ---------------- -- Initialize -- ---------------- procedure Initialize is begin Pending_Descriptor.Init; Pending_Instantiations.Init; Inlined_Bodies.Init; Successors.Init; Inlined.Init; for J in Hash_Headers'Range loop Hash_Headers (J) := No_Subp; end loop; Inlined_Calls := No_Elist; Backend_Calls := No_Elist; Backend_Inlined_Subps := No_Elist; Backend_Not_Inlined_Subps := No_Elist; end Initialize; ------------------------ -- Instantiate_Bodies -- ------------------------ -- Generic bodies contain all the non-local references, so an -- instantiation does not need any more context than Standard -- itself, even if the instantiation appears in an inner scope. -- Generic associations have verified that the contract model is -- satisfied, so that any error that may occur in the analysis of -- the body is an internal error. procedure Instantiate_Bodies is J : Nat; Info : Pending_Body_Info; begin if Serious_Errors_Detected = 0 then Expander_Active := (Operating_Mode = Opt.Generate_Code); Push_Scope (Standard_Standard); To_Clean := New_Elmt_List; if Is_Generic_Unit (Cunit_Entity (Main_Unit)) then Start_Generic; end if; -- A body instantiation may generate additional instantiations, so -- the following loop must scan to the end of a possibly expanding -- set (that's why we can't simply use a FOR loop here). J := 0; while J <= Pending_Instantiations.Last and then Serious_Errors_Detected = 0 loop Info := Pending_Instantiations.Table (J); -- If the instantiation node is absent, it has been removed -- as part of unreachable code. if No (Info.Inst_Node) then null; elsif Nkind (Info.Act_Decl) = N_Package_Declaration then Instantiate_Package_Body (Info); Add_Scope_To_Clean (Defining_Entity (Info.Act_Decl)); else Instantiate_Subprogram_Body (Info); end if; J := J + 1; end loop; -- Reset the table of instantiations. Additional instantiations -- may be added through inlining, when additional bodies are -- analyzed. Pending_Instantiations.Init; -- We can now complete the cleanup actions of scopes that contain -- pending instantiations (skipped for generic units, since we -- never need any cleanups in generic units). if Expander_Active and then not Is_Generic_Unit (Main_Unit_Entity) then Cleanup_Scopes; elsif Is_Generic_Unit (Cunit_Entity (Main_Unit)) then End_Generic; end if; Pop_Scope; end if; end Instantiate_Bodies; --------------- -- Is_Nested -- --------------- function Is_Nested (E : Entity_Id) return Boolean is Scop : Entity_Id; begin Scop := Scope (E); while Scop /= Standard_Standard loop if Ekind (Scop) in Subprogram_Kind then return True; elsif Ekind (Scop) = E_Task_Type or else Ekind (Scop) = E_Entry or else Ekind (Scop) = E_Entry_Family then return True; end if; Scop := Scope (Scop); end loop; return False; end Is_Nested; ------------------------ -- List_Inlining_Info -- ------------------------ procedure List_Inlining_Info is Elmt : Elmt_Id; Nod : Node_Id; Count : Nat; begin if not Debug_Flag_Dot_J then return; end if; -- Generate listing of calls inlined by the frontend if Present (Inlined_Calls) then Count := 0; Elmt := First_Elmt (Inlined_Calls); while Present (Elmt) loop Nod := Node (Elmt); if In_Extended_Main_Code_Unit (Nod) then Count := Count + 1; if Count = 1 then Write_Str ("List of calls inlined by the frontend"); Write_Eol; end if; Write_Str (" "); Write_Int (Count); Write_Str (":"); Write_Location (Sloc (Nod)); Write_Str (":"); Output.Write_Eol; end if; Next_Elmt (Elmt); end loop; end if; -- Generate listing of calls passed to the backend if Present (Backend_Calls) then Count := 0; Elmt := First_Elmt (Backend_Calls); while Present (Elmt) loop Nod := Node (Elmt); if In_Extended_Main_Code_Unit (Nod) then Count := Count + 1; if Count = 1 then Write_Str ("List of inlined calls passed to the backend"); Write_Eol; end if; Write_Str (" "); Write_Int (Count); Write_Str (":"); Write_Location (Sloc (Nod)); Output.Write_Eol; end if; Next_Elmt (Elmt); end loop; end if; -- Generate listing of subprograms passed to the backend if Present (Backend_Inlined_Subps) and then Back_End_Inlining then Count := 0; Elmt := First_Elmt (Backend_Inlined_Subps); while Present (Elmt) loop Nod := Node (Elmt); Count := Count + 1; if Count = 1 then Write_Str ("List of inlined subprograms passed to the backend"); Write_Eol; end if; Write_Str (" "); Write_Int (Count); Write_Str (":"); Write_Name (Chars (Nod)); Write_Str (" ("); Write_Location (Sloc (Nod)); Write_Str (")"); Output.Write_Eol; Next_Elmt (Elmt); end loop; end if; -- Generate listing of subprograms that cannot be inlined by the backend if Present (Backend_Not_Inlined_Subps) and then Back_End_Inlining then Count := 0; Elmt := First_Elmt (Backend_Not_Inlined_Subps); while Present (Elmt) loop Nod := Node (Elmt); Count := Count + 1; if Count = 1 then Write_Str ("List of subprograms that cannot be inlined by the backend"); Write_Eol; end if; Write_Str (" "); Write_Int (Count); Write_Str (":"); Write_Name (Chars (Nod)); Write_Str (" ("); Write_Location (Sloc (Nod)); Write_Str (")"); Output.Write_Eol; Next_Elmt (Elmt); end loop; end if; end List_Inlining_Info; ---------- -- Lock -- ---------- procedure Lock is begin Pending_Instantiations.Release; Pending_Instantiations.Locked := True; Inlined_Bodies.Release; Inlined_Bodies.Locked := True; Successors.Release; Successors.Locked := True; Inlined.Release; Inlined.Locked := True; end Lock; -------------------------------- -- Remove_Aspects_And_Pragmas -- -------------------------------- procedure Remove_Aspects_And_Pragmas (Body_Decl : Node_Id) is procedure Remove_Items (List : List_Id); -- Remove all useless aspects/pragmas from a particular list ------------------ -- Remove_Items -- ------------------ procedure Remove_Items (List : List_Id) is Item : Node_Id; Item_Id : Node_Id; Next_Item : Node_Id; begin -- Traverse the list looking for an aspect specification or a pragma Item := First (List); while Present (Item) loop Next_Item := Next (Item); if Nkind (Item) = N_Aspect_Specification then Item_Id := Identifier (Item); elsif Nkind (Item) = N_Pragma then Item_Id := Pragma_Identifier (Item); else Item_Id := Empty; end if; if Present (Item_Id) and then Nam_In (Chars (Item_Id), Name_Contract_Cases, Name_Global, Name_Depends, Name_Postcondition, Name_Precondition, Name_Refined_Global, Name_Refined_Depends, Name_Refined_Post, Name_Test_Case, Name_Unmodified, Name_Unreferenced, Name_Unused) then Remove (Item); end if; Item := Next_Item; end loop; end Remove_Items; -- Start of processing for Remove_Aspects_And_Pragmas begin Remove_Items (Aspect_Specifications (Body_Decl)); Remove_Items (Declarations (Body_Decl)); -- Pragmas Unmodified, Unreferenced, and Unused may additionally appear -- in the body of the subprogram. Remove_Items (Statements (Handled_Statement_Sequence (Body_Decl))); end Remove_Aspects_And_Pragmas; -------------------------- -- Remove_Dead_Instance -- -------------------------- procedure Remove_Dead_Instance (N : Node_Id) is J : Int; begin J := 0; while J <= Pending_Instantiations.Last loop if Pending_Instantiations.Table (J).Inst_Node = N then Pending_Instantiations.Table (J).Inst_Node := Empty; return; end if; J := J + 1; end loop; end Remove_Dead_Instance; end Inline;