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author | upstream source tree <ports@midipix.org> | 2015-03-15 20:14:05 -0400 |
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committer | upstream source tree <ports@midipix.org> | 2015-03-15 20:14:05 -0400 |
commit | 554fd8c5195424bdbcabf5de30fdc183aba391bd (patch) | |
tree | 976dc5ab7fddf506dadce60ae936f43f58787092 /gcc/ada/inline.adb | |
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Diffstat (limited to 'gcc/ada/inline.adb')
-rw-r--r-- | gcc/ada/inline.adb | 1233 |
1 files changed, 1233 insertions, 0 deletions
diff --git a/gcc/ada/inline.adb b/gcc/ada/inline.adb new file mode 100644 index 000000000..f40edd92d --- /dev/null +++ b/gcc/ada/inline.adb @@ -0,0 +1,1233 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT COMPILER COMPONENTS -- +-- -- +-- I N L I N E -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 1992-2010, 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 Atree; use Atree; +with Einfo; use Einfo; +with Elists; use Elists; +with Errout; use Errout; +with Exp_Ch7; use Exp_Ch7; +with Exp_Tss; use Exp_Tss; +with Fname; use Fname; +with Fname.UF; use Fname.UF; +with Lib; use Lib; +with Namet; use Namet; +with Nlists; use Nlists; +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_Util; use Sem_Util; +with Sinfo; use Sinfo; +with Snames; use Snames; +with Stand; use Stand; +with Uname; use Uname; + +package body Inline is + + -------------------- + -- 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 a prerequisite 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 produce a list of subprograms in topological order, for use by the + -- back-end. If P2 is a prerequisite of P1, then P1 calls P2, and for + -- proper inlining the back-end must analyze the body of P2 before that of + -- P1. The code below guarantees that the transitive closure of inlined + -- subprograms called from the main compilation unit is made available to + -- the code generator. + + 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; + First_Succ : Succ_Index := No_Succ; + Count : Integer := 0; + Listed : Boolean := False; + Main_Call : Boolean := False; + Next : Subp_Index := No_Subp; + Next_Nopred : Subp_Index := No_Subp; + 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 -- + ----------------------- + + function Scope_In_Main_Unit (Scop : Entity_Id) return Boolean; + -- Return True if Scop is in the main unit or its spec + + 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. + + 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 Has_Initialized_Type (E : Entity_Id) return Boolean; + -- If a candidate for inlining contains type declarations for types with + -- non-trivial initialization procedures, they are not worth inlining. + + 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 Add_Inlined_Subprogram (Index : Subp_Index); + -- Add subprogram to Inlined List once all of its predecessors have been + -- placed on the list. Decrement the count of all its successors, and + -- add them to list (recursively) if count drops to zero. + + ------------------------------ + -- 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 P2 to the list of successors of P1, 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 (P1).First_Succ; + while J /= No_Succ loop + if Successors.Table (J).Subp = P2 then + return; + end if; + + J := Successors.Table (J).Next; + end loop; + + -- On exit, make a successor entry for P2 + + Successors.Increment_Last; + Successors.Table (Successors.Last).Subp := P2; + Successors.Table (Successors.Last).Next := + Inlined.Table (P1).First_Succ; + Inlined.Table (P1).First_Succ := Successors.Last; + + Inlined.Table (P2).Count := Inlined.Table (P2).Count + 1; + + else + Inlined.Table (P1).Main_Call := True; + end if; + end Add_Call; + + ---------------------- + -- Add_Inlined_Body -- + ---------------------- + + procedure Add_Inlined_Body (E : Entity_Id) is + Pack : Entity_Id; + + function Must_Inline return Boolean; + -- 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 Boolean 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 False; + 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 Comp = Cunit (Main_Unit) + or else Comp = Library_Unit (Cunit (Main_Unit)) + then + Add_Call (E); + return True; + end if; + + -- Call is not in main unit. See if it's in some inlined subprogram + + 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) + then + Add_Call (E, Scop); + return True; + end if; + + Scop := Scope (Scop); + end loop; + + return False; + end Must_Inline; + + -- Start of processing for Add_Inlined_Body + + begin + -- 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. + + if not Is_Abstract_Subprogram (E) and then not Is_Nested (E) + and then Convention (E) /= Convention_Protected + then + Pack := Scope (E); + + if Must_Inline + and then Ekind (Pack) = E_Package + then + Set_Is_Called (E); + + if Pack = Standard_Standard then + + -- Library-level inlined function. Add function itself to + -- list of needed units. + + Inlined_Bodies.Increment_Last; + Inlined_Bodies.Table (Inlined_Bodies.Last) := E; + + elsif Is_Generic_Instance (Pack) then + null; + + elsif not Is_Inlined (Pack) + and then not Has_Completion (E) + then + Set_Is_Inlined (Pack); + Inlined_Bodies.Increment_Last; + Inlined_Bodies.Table (Inlined_Bodies.Last) := Pack; + end if; + end if; + end if; + end Add_Inlined_Body; + + ---------------------------- + -- Add_Inlined_Subprogram -- + ---------------------------- + + procedure Add_Inlined_Subprogram (Index : Subp_Index) is + E : constant Entity_Id := Inlined.Table (Index).Name; + Pack : constant Entity_Id := Cunit_Entity (Get_Code_Unit (E)); + Succ : Succ_Index; + Subp : Subp_Index; + + function Back_End_Cannot_Inline (Subp : Entity_Id) return Boolean; + -- There are various conditions under which back-end inlining cannot + -- be done reliably: + -- + -- a) If a body has handlers, it must not be inlined, because this + -- may violate program semantics, and because in zero-cost exception + -- mode it will lead to undefined symbols at link time. + -- + -- b) If a body contains inlined function instances, it cannot be + -- inlined under ZCX because the numeric suffix generated by gigi + -- will be different in the body and the place of the inlined call. + -- + -- If the body to be inlined contains calls to subprograms declared + -- in the same body that have no previous spec, the back-end cannot + -- inline either because the bodies to be inlined are processed before + -- the rest of the enclosing package body, and gigi will then find + -- references to entities that have not been elaborated yet. + -- + -- This procedure must be carefully coordinated with the back end. + + ---------------------------- + -- Back_End_Cannot_Inline -- + ---------------------------- + + function Back_End_Cannot_Inline (Subp : Entity_Id) return Boolean is + Decl : constant Node_Id := Unit_Declaration_Node (Subp); + Body_Ent : Entity_Id; + Ent : Entity_Id; + Bad_Call : Node_Id; + + function Process (N : Node_Id) return Traverse_Result; + -- Look for calls to subprograms with no previous spec, declared + -- in the same enclosing package body. + + ------------- + -- Process -- + ------------- + + function Process (N : Node_Id) return Traverse_Result is + begin + if Nkind (N) = N_Procedure_Call_Statement + or else Nkind (N) = N_Function_Call + then + if Is_Entity_Name (Name (N)) + and then Comes_From_Source (Entity (Name (N))) + and then + Nkind (Unit_Declaration_Node (Entity (Name (N)))) + = N_Subprogram_Body + and then In_Same_Extended_Unit (Subp, Entity (Name (N))) + then + Bad_Call := N; + return Abandon; + else + return OK; + end if; + else + return OK; + end if; + end Process; + + function Has_Exposed_Call is new Traverse_Func (Process); + + -- Start of processing for Back_End_Cannot_Inline + + begin + if Nkind (Decl) = N_Subprogram_Declaration + and then Present (Corresponding_Body (Decl)) + then + Body_Ent := Corresponding_Body (Decl); + else + return False; + end if; + + -- If subprogram is marked Inline_Always, inlining is mandatory + + if Has_Pragma_Inline_Always (Subp) then + return False; + end if; + + if Present + (Exception_Handlers + (Handled_Statement_Sequence + (Unit_Declaration_Node (Corresponding_Body (Decl))))) + then + return True; + end if; + + Ent := First_Entity (Body_Ent); + while Present (Ent) loop + if Is_Subprogram (Ent) + and then Is_Generic_Instance (Ent) + then + return True; + end if; + + Next_Entity (Ent); + end loop; + + if Has_Exposed_Call + (Unit_Declaration_Node (Corresponding_Body (Decl))) = Abandon + then + if Ineffective_Inline_Warnings then + Error_Msg_N + ("?call to subprogram with no separate spec" + & " prevents inlining!!", Bad_Call); + end if; + + return True; + else + return False; + end if; + end Back_End_Cannot_Inline; + + -- Start of processing for Add_Inlined_Subprogram + + begin + -- Insert the current subprogram in the list of inlined subprograms, if + -- it can actually be inlined by the back-end, and if its unit is known + -- to be inlined, or is an instance whose body will be analyzed anyway. + + if (Is_Inlined (Pack) or else Is_Generic_Instance (Pack)) + and then not Scope_In_Main_Unit (E) + and then Is_Inlined (E) + and then not Is_Nested (E) + and then not Has_Initialized_Type (E) + then + if Back_End_Cannot_Inline (E) then + Set_Is_Inlined (E, False); + + else + 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; + end if; + end if; + + Inlined.Table (Index).Listed := True; + + -- Now add to the list those callers of the current subprogram that + -- are themselves called. They may appear on the graph as callers + -- of the current one, even if they are themselves not called, and + -- there is no point in including them in the list for the backend. + -- Furthermore, they might not even be public, in which case the + -- back-end cannot handle them at all. + + Succ := Inlined.Table (Index).First_Succ; + while Succ /= No_Succ loop + Subp := Successors.Table (Succ).Subp; + Inlined.Table (Subp).Count := Inlined.Table (Subp).Count - 1; + + if Inlined.Table (Subp).Count = 0 + and then Is_Called (Inlined.Table (Subp).Name) + then + Add_Inlined_Subprogram (Subp); + end if; + + Succ := Successors.Table (Succ).Next; + end loop; + 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 appears within a generic subprogram there is nothing + -- to finalize either. + + declare + S : Entity_Id; + + begin + S := Scope (Inst); + while Present (S) and then S /= Standard_Standard loop + if Is_Generic_Subprogram (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).First_Succ := No_Succ; + Inlined.Table (Inlined.Last).Count := 0; + Inlined.Table (Inlined.Last).Listed := False; + Inlined.Table (Inlined.Last).Main_Call := False; + Inlined.Table (Inlined.Last).Next := No_Subp; + Inlined.Table (Inlined.Last).Next_Nopred := No_Subp; + 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; + S : Succ_Index; + + function Is_Ancestor_Of_Main + (U_Name : Entity_Id; + Nam : Node_Id) return Boolean; + -- Determine whether the unit whose body is loaded is an ancestor of + -- the main unit, and has a with_clause on it. The body is not + -- analyzed yet, so the check is purely lexical: the name of the with + -- clause is a selected component, and names of ancestors must match. + + ------------------------- + -- Is_Ancestor_Of_Main -- + ------------------------- + + function Is_Ancestor_Of_Main + (U_Name : Entity_Id; + Nam : Node_Id) return Boolean + is + Pref : Node_Id; + + begin + if Nkind (Nam) /= N_Selected_Component then + return False; + + else + if Chars (Selector_Name (Nam)) /= + Chars (Cunit_Entity (Main_Unit)) + then + return False; + end if; + + Pref := Prefix (Nam); + if Nkind (Pref) = N_Identifier then + + -- Par is an ancestor of Par.Child. + + return Chars (Pref) = Chars (U_Name); + + elsif Nkind (Pref) = N_Selected_Component + and then Chars (Selector_Name (Pref)) = Chars (U_Name) + then + -- Par.Child is an ancestor of Par.Child.Grand. + + return True; -- should check that ancestor match + + else + -- A is an ancestor of A.B.C if it is an ancestor of A.B + + return Is_Ancestor_Of_Main (U_Name, Pref); + end if; + end if; + end Is_Ancestor_Of_Main; + + -- Start of processing for Analyze_Inlined_Bodies + + begin + Analyzing_Inlined_Bodies := False; + + 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, unless it 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)))) + 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, Do_Analyze => False); + + 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); + + else + -- If the package to be inlined is an ancestor unit of + -- the main unit, and it has a semantic dependence on + -- it, the inlining cannot take place to prevent an + -- elaboration circularity. The desired body is not + -- analyzed yet, to prevent the completion of Taft + -- amendment types that would lead to elaboration + -- circularities in gigi. + + declare + U_Id : constant Entity_Id := + Defining_Entity (Unit (Comp_Unit)); + Body_Unit : constant Node_Id := + Library_Unit (Comp_Unit); + Item : Node_Id; + + begin + Item := First (Context_Items (Body_Unit)); + while Present (Item) loop + if Nkind (Item) = N_With_Clause + and then + Is_Ancestor_Of_Main (U_Id, Name (Item)) + then + Set_Is_Inlined (U_Id, False); + exit; + end if; + + Next (Item); + end loop; + + -- If no suspicious with_clauses, analyze the body. + + if Is_Inlined (U_Id) then + Semantics (Body_Unit); + end if; + end; + end if; + end if; + end; + end if; + + J := J + 1; + end loop; + + -- The analysis of required bodies may have produced additional + -- generic instantiations. To obtain further inlining, we perform + -- another round of generic body instantiations. Establishing a + -- fully recursive loop between inlining and generic instantiations + -- is unlikely to yield more than this one additional pass. + + Instantiate_Bodies; + + -- 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 program. Here we do one step of + -- the inverse transitive closure, and reset the Is_Called flag on + -- subprograms all of whose callers are not. + + for Index in Inlined.First .. Inlined.Last loop + S := Inlined.Table (Index).First_Succ; + + if S /= No_Succ + and then not Inlined.Table (Index).Main_Call + then + Set_Is_Called (Inlined.Table (Index).Name, False); + + while S /= No_Succ loop + if Is_Called + (Inlined.Table (Successors.Table (S).Subp).Name) + or else Inlined.Table (Successors.Table (S).Subp).Main_Call + then + Set_Is_Called (Inlined.Table (Index).Name); + exit; + end if; + + S := Successors.Table (S).Next; + end loop; + end if; + end loop; + + -- Now that the units are compiled, chain the subprograms within + -- that are called and inlined. Produce list of inlined subprograms + -- sorted in topological order. Start with all subprograms that + -- have no prerequisites, i.e. inlined subprograms that do not call + -- other inlined subprograms. + + for Index in Inlined.First .. Inlined.Last loop + + if Is_Called (Inlined.Table (Index).Name) + and then Inlined.Table (Index).Count = 0 + and then not Inlined.Table (Index).Listed + then + Add_Inlined_Subprogram (Index); + end if; + end loop; + + -- Because Add_Inlined_Subprogram treats recursively nodes that have + -- no prerequisites left, at the end of the loop all subprograms + -- must have been listed. If there are any unlisted subprograms + -- left, there must be some recursive chains that cannot be inlined. + + for Index in Inlined.First .. Inlined.Last loop + if Is_Called (Inlined.Table (Index).Name) + and then Inlined.Table (Index).Count /= 0 + and then not Is_Predefined_File_Name + (Unit_File_Name + (Get_Source_Unit (Inlined.Table (Index).Name))) + then + Error_Msg_N + ("& cannot be inlined?", Inlined.Table (Index).Name); + + -- A warning on the first one might be sufficient ??? + end if; + end loop; + + Pop_Scope; + end if; + end Analyze_Inlined_Bodies; + + ----------------------------- + -- Check_Body_For_Inlining -- + ----------------------------- + + procedure Check_Body_For_Inlining (N : Node_Id; P : Entity_Id) is + Bname : Unit_Name_Type; + E : Entity_Id; + OK : Boolean; + + begin + if 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 (Front_End_Inlining and then Has_Pragma_Inline (E)) + 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_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)); + Set_Finalization_Chain_Entity + (Protected_Body_Subprogram (Scop), + Finalization_Chain_Entity (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 (Decl) = N_Subprogram_Declaration + or else Nkind (Decl) = N_Task_Type_Declaration + or else Nkind (Decl) = 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; + + -------------------------- + -- Has_Initialized_Type -- + -------------------------- + + function Has_Initialized_Type (E : Entity_Id) return Boolean is + E_Body : constant Node_Id := Get_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; + + ---------------- + -- Initialize -- + ---------------- + + procedure Initialize is + begin + Analyzing_Inlined_Bodies := False; + 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; + 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 : Int; + 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). + -- pending instantiations. + + 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; + + ---------- + -- Lock -- + ---------- + + procedure Lock is + begin + Pending_Instantiations.Locked := True; + Inlined_Bodies.Locked := True; + Successors.Locked := True; + Inlined.Locked := True; + Pending_Instantiations.Release; + Inlined_Bodies.Release; + Successors.Release; + Inlined.Release; + end Lock; + + -------------------------- + -- 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; + + ------------------------ + -- Scope_In_Main_Unit -- + ------------------------ + + function Scope_In_Main_Unit (Scop : Entity_Id) return Boolean is + Comp : constant Node_Id := Cunit (Get_Code_Unit (Scop)); + + begin + -- Check whether the scope of the subprogram to inline is within the + -- main unit or within its spec. 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. + + return + Comp = Cunit (Main_Unit) + or else Comp = Library_Unit (Cunit (Main_Unit)); + end Scope_In_Main_Unit; + +end Inline; |