| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- E X P _ U T I L -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2013, 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 Casing; use Casing; |
| with Checks; use Checks; |
| with Debug; use Debug; |
| with Einfo; use Einfo; |
| with Elists; use Elists; |
| with Errout; use Errout; |
| with Exp_Aggr; use Exp_Aggr; |
| with Exp_Ch6; use Exp_Ch6; |
| with Exp_Ch7; use Exp_Ch7; |
| with Inline; use Inline; |
| with Itypes; use Itypes; |
| with Lib; use Lib; |
| with Nlists; use Nlists; |
| with Nmake; use Nmake; |
| with Opt; use Opt; |
| with Restrict; use Restrict; |
| with Rident; use Rident; |
| with Sem; use Sem; |
| with Sem_Aux; use Sem_Aux; |
| with Sem_Ch8; use Sem_Ch8; |
| with Sem_Eval; use Sem_Eval; |
| with Sem_Prag; use Sem_Prag; |
| with Sem_Res; use Sem_Res; |
| with Sem_Type; use Sem_Type; |
| with Sem_Util; use Sem_Util; |
| with Snames; use Snames; |
| with Stand; use Stand; |
| with Stringt; use Stringt; |
| with Targparm; use Targparm; |
| with Tbuild; use Tbuild; |
| with Ttypes; use Ttypes; |
| with Urealp; use Urealp; |
| with Validsw; use Validsw; |
| |
| package body Exp_Util is |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| function Build_Task_Array_Image |
| (Loc : Source_Ptr; |
| Id_Ref : Node_Id; |
| A_Type : Entity_Id; |
| Dyn : Boolean := False) return Node_Id; |
| -- Build function to generate the image string for a task that is an array |
| -- component, concatenating the images of each index. To avoid storage |
| -- leaks, the string is built with successive slice assignments. The flag |
| -- Dyn indicates whether this is called for the initialization procedure of |
| -- an array of tasks, or for the name of a dynamically created task that is |
| -- assigned to an indexed component. |
| |
| function Build_Task_Image_Function |
| (Loc : Source_Ptr; |
| Decls : List_Id; |
| Stats : List_Id; |
| Res : Entity_Id) return Node_Id; |
| -- Common processing for Task_Array_Image and Task_Record_Image. Build |
| -- function body that computes image. |
| |
| procedure Build_Task_Image_Prefix |
| (Loc : Source_Ptr; |
| Len : out Entity_Id; |
| Res : out Entity_Id; |
| Pos : out Entity_Id; |
| Prefix : Entity_Id; |
| Sum : Node_Id; |
| Decls : List_Id; |
| Stats : List_Id); |
| -- Common processing for Task_Array_Image and Task_Record_Image. Create |
| -- local variables and assign prefix of name to result string. |
| |
| function Build_Task_Record_Image |
| (Loc : Source_Ptr; |
| Id_Ref : Node_Id; |
| Dyn : Boolean := False) return Node_Id; |
| -- Build function to generate the image string for a task that is a record |
| -- component. Concatenate name of variable with that of selector. The flag |
| -- Dyn indicates whether this is called for the initialization procedure of |
| -- record with task components, or for a dynamically created task that is |
| -- assigned to a selected component. |
| |
| function Make_CW_Equivalent_Type |
| (T : Entity_Id; |
| E : Node_Id) return Entity_Id; |
| -- T is a class-wide type entity, E is the initial expression node that |
| -- constrains T in case such as: " X: T := E" or "new T'(E)". This function |
| -- returns the entity of the Equivalent type and inserts on the fly the |
| -- necessary declaration such as: |
| -- |
| -- type anon is record |
| -- _parent : Root_Type (T); constrained with E discriminants (if any) |
| -- Extension : String (1 .. expr to match size of E); |
| -- end record; |
| -- |
| -- This record is compatible with any object of the class of T thanks to |
| -- the first field and has the same size as E thanks to the second. |
| |
| function Make_Literal_Range |
| (Loc : Source_Ptr; |
| Literal_Typ : Entity_Id) return Node_Id; |
| -- Produce a Range node whose bounds are: |
| -- Low_Bound (Literal_Type) .. |
| -- Low_Bound (Literal_Type) + (Length (Literal_Typ) - 1) |
| -- this is used for expanding declarations like X : String := "sdfgdfg"; |
| -- |
| -- If the index type of the target array is not integer, we generate: |
| -- Low_Bound (Literal_Type) .. |
| -- Literal_Type'Val |
| -- (Literal_Type'Pos (Low_Bound (Literal_Type)) |
| -- + (Length (Literal_Typ) -1)) |
| |
| function Make_Non_Empty_Check |
| (Loc : Source_Ptr; |
| N : Node_Id) return Node_Id; |
| -- Produce a boolean expression checking that the unidimensional array |
| -- node N is not empty. |
| |
| function New_Class_Wide_Subtype |
| (CW_Typ : Entity_Id; |
| N : Node_Id) return Entity_Id; |
| -- Create an implicit subtype of CW_Typ attached to node N |
| |
| function Requires_Cleanup_Actions |
| (L : List_Id; |
| Lib_Level : Boolean; |
| Nested_Constructs : Boolean) return Boolean; |
| -- Given a list L, determine whether it contains one of the following: |
| -- |
| -- 1) controlled objects |
| -- 2) library-level tagged types |
| -- |
| -- Lib_Level is True when the list comes from a construct at the library |
| -- level, and False otherwise. Nested_Constructs is True when any nested |
| -- packages declared in L must be processed, and False otherwise. |
| |
| ------------------------------------- |
| -- Activate_Atomic_Synchronization -- |
| ------------------------------------- |
| |
| procedure Activate_Atomic_Synchronization (N : Node_Id) is |
| Msg_Node : Node_Id; |
| |
| begin |
| case Nkind (Parent (N)) is |
| |
| -- Check for cases of appearing in the prefix of a construct where |
| -- we don't need atomic synchronization for this kind of usage. |
| |
| when |
| -- Nothing to do if we are the prefix of an attribute, since we |
| -- do not want an atomic sync operation for things like 'Size. |
| |
| N_Attribute_Reference | |
| |
| -- The N_Reference node is like an attribute |
| |
| N_Reference | |
| |
| -- Nothing to do for a reference to a component (or components) |
| -- of a composite object. Only reads and updates of the object |
| -- as a whole require atomic synchronization (RM C.6 (15)). |
| |
| N_Indexed_Component | |
| N_Selected_Component | |
| N_Slice => |
| |
| -- For all the above cases, nothing to do if we are the prefix |
| |
| if Prefix (Parent (N)) = N then |
| return; |
| end if; |
| |
| when others => null; |
| end case; |
| |
| -- Go ahead and set the flag |
| |
| Set_Atomic_Sync_Required (N); |
| |
| -- Generate info message if requested |
| |
| if Warn_On_Atomic_Synchronization then |
| case Nkind (N) is |
| when N_Identifier => |
| Msg_Node := N; |
| |
| when N_Selected_Component | N_Expanded_Name => |
| Msg_Node := Selector_Name (N); |
| |
| when N_Explicit_Dereference | N_Indexed_Component => |
| Msg_Node := Empty; |
| |
| when others => |
| pragma Assert (False); |
| return; |
| end case; |
| |
| if Present (Msg_Node) then |
| Error_Msg_N |
| ("?N?info: atomic synchronization set for &", Msg_Node); |
| else |
| Error_Msg_N |
| ("?N?info: atomic synchronization set", N); |
| end if; |
| end if; |
| end Activate_Atomic_Synchronization; |
| |
| ---------------------- |
| -- Adjust_Condition -- |
| ---------------------- |
| |
| procedure Adjust_Condition (N : Node_Id) is |
| begin |
| if No (N) then |
| return; |
| end if; |
| |
| declare |
| Loc : constant Source_Ptr := Sloc (N); |
| T : constant Entity_Id := Etype (N); |
| Ti : Entity_Id; |
| |
| begin |
| -- Defend against a call where the argument has no type, or has a |
| -- type that is not Boolean. This can occur because of prior errors. |
| |
| if No (T) or else not Is_Boolean_Type (T) then |
| return; |
| end if; |
| |
| -- Apply validity checking if needed |
| |
| if Validity_Checks_On and Validity_Check_Tests then |
| Ensure_Valid (N); |
| end if; |
| |
| -- Immediate return if standard boolean, the most common case, |
| -- where nothing needs to be done. |
| |
| if Base_Type (T) = Standard_Boolean then |
| return; |
| end if; |
| |
| -- Case of zero/non-zero semantics or non-standard enumeration |
| -- representation. In each case, we rewrite the node as: |
| |
| -- ityp!(N) /= False'Enum_Rep |
| |
| -- where ityp is an integer type with large enough size to hold any |
| -- value of type T. |
| |
| if Nonzero_Is_True (T) or else Has_Non_Standard_Rep (T) then |
| if Esize (T) <= Esize (Standard_Integer) then |
| Ti := Standard_Integer; |
| else |
| Ti := Standard_Long_Long_Integer; |
| end if; |
| |
| Rewrite (N, |
| Make_Op_Ne (Loc, |
| Left_Opnd => Unchecked_Convert_To (Ti, N), |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Enum_Rep, |
| Prefix => |
| New_Occurrence_Of (First_Literal (T), Loc)))); |
| Analyze_And_Resolve (N, Standard_Boolean); |
| |
| else |
| Rewrite (N, Convert_To (Standard_Boolean, N)); |
| Analyze_And_Resolve (N, Standard_Boolean); |
| end if; |
| end; |
| end Adjust_Condition; |
| |
| ------------------------ |
| -- Adjust_Result_Type -- |
| ------------------------ |
| |
| procedure Adjust_Result_Type (N : Node_Id; T : Entity_Id) is |
| begin |
| -- Ignore call if current type is not Standard.Boolean |
| |
| if Etype (N) /= Standard_Boolean then |
| return; |
| end if; |
| |
| -- If result is already of correct type, nothing to do. Note that |
| -- this will get the most common case where everything has a type |
| -- of Standard.Boolean. |
| |
| if Base_Type (T) = Standard_Boolean then |
| return; |
| |
| else |
| declare |
| KP : constant Node_Kind := Nkind (Parent (N)); |
| |
| begin |
| -- If result is to be used as a Condition in the syntax, no need |
| -- to convert it back, since if it was changed to Standard.Boolean |
| -- using Adjust_Condition, that is just fine for this usage. |
| |
| if KP in N_Raise_xxx_Error or else KP in N_Has_Condition then |
| return; |
| |
| -- If result is an operand of another logical operation, no need |
| -- to reset its type, since Standard.Boolean is just fine, and |
| -- such operations always do Adjust_Condition on their operands. |
| |
| elsif KP in N_Op_Boolean |
| or else KP in N_Short_Circuit |
| or else KP = N_Op_Not |
| then |
| return; |
| |
| -- Otherwise we perform a conversion from the current type, which |
| -- must be Standard.Boolean, to the desired type. |
| |
| else |
| Set_Analyzed (N); |
| Rewrite (N, Convert_To (T, N)); |
| Analyze_And_Resolve (N, T); |
| end if; |
| end; |
| end if; |
| end Adjust_Result_Type; |
| |
| -------------------------- |
| -- Append_Freeze_Action -- |
| -------------------------- |
| |
| procedure Append_Freeze_Action (T : Entity_Id; N : Node_Id) is |
| Fnode : Node_Id; |
| |
| begin |
| Ensure_Freeze_Node (T); |
| Fnode := Freeze_Node (T); |
| |
| if No (Actions (Fnode)) then |
| Set_Actions (Fnode, New_List (N)); |
| else |
| Append (N, Actions (Fnode)); |
| end if; |
| |
| end Append_Freeze_Action; |
| |
| --------------------------- |
| -- Append_Freeze_Actions -- |
| --------------------------- |
| |
| procedure Append_Freeze_Actions (T : Entity_Id; L : List_Id) is |
| Fnode : Node_Id; |
| |
| begin |
| if No (L) then |
| return; |
| end if; |
| |
| Ensure_Freeze_Node (T); |
| Fnode := Freeze_Node (T); |
| |
| if No (Actions (Fnode)) then |
| Set_Actions (Fnode, L); |
| else |
| Append_List (L, Actions (Fnode)); |
| end if; |
| end Append_Freeze_Actions; |
| |
| ------------------------------------ |
| -- Build_Allocate_Deallocate_Proc -- |
| ------------------------------------ |
| |
| procedure Build_Allocate_Deallocate_Proc |
| (N : Node_Id; |
| Is_Allocate : Boolean) |
| is |
| Desig_Typ : Entity_Id; |
| Expr : Node_Id; |
| Pool_Id : Entity_Id; |
| Proc_To_Call : Node_Id := Empty; |
| Ptr_Typ : Entity_Id; |
| |
| function Find_Finalize_Address (Typ : Entity_Id) return Entity_Id; |
| -- Locate TSS primitive Finalize_Address in type Typ |
| |
| function Find_Object (E : Node_Id) return Node_Id; |
| -- Given an arbitrary expression of an allocator, try to find an object |
| -- reference in it, otherwise return the original expression. |
| |
| function Is_Allocate_Deallocate_Proc (Subp : Entity_Id) return Boolean; |
| -- Determine whether subprogram Subp denotes a custom allocate or |
| -- deallocate. |
| |
| --------------------------- |
| -- Find_Finalize_Address -- |
| --------------------------- |
| |
| function Find_Finalize_Address (Typ : Entity_Id) return Entity_Id is |
| Utyp : Entity_Id := Typ; |
| |
| begin |
| -- Handle protected class-wide or task class-wide types |
| |
| if Is_Class_Wide_Type (Utyp) then |
| if Is_Concurrent_Type (Root_Type (Utyp)) then |
| Utyp := Root_Type (Utyp); |
| |
| elsif Is_Private_Type (Root_Type (Utyp)) |
| and then Present (Full_View (Root_Type (Utyp))) |
| and then Is_Concurrent_Type (Full_View (Root_Type (Utyp))) |
| then |
| Utyp := Full_View (Root_Type (Utyp)); |
| end if; |
| end if; |
| |
| -- Handle private types |
| |
| if Is_Private_Type (Utyp) and then Present (Full_View (Utyp)) then |
| Utyp := Full_View (Utyp); |
| end if; |
| |
| -- Handle protected and task types |
| |
| if Is_Concurrent_Type (Utyp) |
| and then Present (Corresponding_Record_Type (Utyp)) |
| then |
| Utyp := Corresponding_Record_Type (Utyp); |
| end if; |
| |
| Utyp := Underlying_Type (Base_Type (Utyp)); |
| |
| -- Deal with non-tagged derivation of private views. If the parent is |
| -- now known to be protected, the finalization routine is the one |
| -- defined on the corresponding record of the ancestor (corresponding |
| -- records do not automatically inherit operations, but maybe they |
| -- should???) |
| |
| if Is_Untagged_Derivation (Typ) then |
| if Is_Protected_Type (Typ) then |
| Utyp := Corresponding_Record_Type (Root_Type (Base_Type (Typ))); |
| else |
| Utyp := Underlying_Type (Root_Type (Base_Type (Typ))); |
| |
| if Is_Protected_Type (Utyp) then |
| Utyp := Corresponding_Record_Type (Utyp); |
| end if; |
| end if; |
| end if; |
| |
| -- If the underlying_type is a subtype, we are dealing with the |
| -- completion of a private type. We need to access the base type and |
| -- generate a conversion to it. |
| |
| if Utyp /= Base_Type (Utyp) then |
| pragma Assert (Is_Private_Type (Typ)); |
| |
| Utyp := Base_Type (Utyp); |
| end if; |
| |
| -- When dealing with an internally built full view for a type with |
| -- unknown discriminants, use the original record type. |
| |
| if Is_Underlying_Record_View (Utyp) then |
| Utyp := Etype (Utyp); |
| end if; |
| |
| return TSS (Utyp, TSS_Finalize_Address); |
| end Find_Finalize_Address; |
| |
| ----------------- |
| -- Find_Object -- |
| ----------------- |
| |
| function Find_Object (E : Node_Id) return Node_Id is |
| Expr : Node_Id; |
| |
| begin |
| pragma Assert (Is_Allocate); |
| |
| Expr := E; |
| loop |
| if Nkind_In (Expr, N_Qualified_Expression, |
| N_Unchecked_Type_Conversion) |
| then |
| Expr := Expression (Expr); |
| |
| elsif Nkind (Expr) = N_Explicit_Dereference then |
| Expr := Prefix (Expr); |
| |
| else |
| exit; |
| end if; |
| end loop; |
| |
| return Expr; |
| end Find_Object; |
| |
| --------------------------------- |
| -- Is_Allocate_Deallocate_Proc -- |
| --------------------------------- |
| |
| function Is_Allocate_Deallocate_Proc (Subp : Entity_Id) return Boolean is |
| begin |
| -- Look for a subprogram body with only one statement which is a |
| -- call to Allocate_Any_Controlled / Deallocate_Any_Controlled. |
| |
| if Ekind (Subp) = E_Procedure |
| and then Nkind (Parent (Parent (Subp))) = N_Subprogram_Body |
| then |
| declare |
| HSS : constant Node_Id := |
| Handled_Statement_Sequence (Parent (Parent (Subp))); |
| Proc : Entity_Id; |
| |
| begin |
| if Present (Statements (HSS)) |
| and then Nkind (First (Statements (HSS))) = |
| N_Procedure_Call_Statement |
| then |
| Proc := Entity (Name (First (Statements (HSS)))); |
| |
| return |
| Is_RTE (Proc, RE_Allocate_Any_Controlled) |
| or else Is_RTE (Proc, RE_Deallocate_Any_Controlled); |
| end if; |
| end; |
| end if; |
| |
| return False; |
| end Is_Allocate_Deallocate_Proc; |
| |
| -- Start of processing for Build_Allocate_Deallocate_Proc |
| |
| begin |
| -- Do not perform this expansion in Alfa mode because it is not |
| -- necessary. |
| |
| if Alfa_Mode then |
| return; |
| end if; |
| |
| -- Obtain the attributes of the allocation / deallocation |
| |
| if Nkind (N) = N_Free_Statement then |
| Expr := Expression (N); |
| Ptr_Typ := Base_Type (Etype (Expr)); |
| Proc_To_Call := Procedure_To_Call (N); |
| |
| else |
| if Nkind (N) = N_Object_Declaration then |
| Expr := Expression (N); |
| else |
| Expr := N; |
| end if; |
| |
| -- In certain cases an allocator with a qualified expression may |
| -- be relocated and used as the initialization expression of a |
| -- temporary: |
| |
| -- before: |
| -- Obj : Ptr_Typ := new Desig_Typ'(...); |
| |
| -- after: |
| -- Tmp : Ptr_Typ := new Desig_Typ'(...); |
| -- Obj : Ptr_Typ := Tmp; |
| |
| -- Since the allocator is always marked as analyzed to avoid infinite |
| -- expansion, it will never be processed by this routine given that |
| -- the designated type needs finalization actions. Detect this case |
| -- and complete the expansion of the allocator. |
| |
| if Nkind (Expr) = N_Identifier |
| and then Nkind (Parent (Entity (Expr))) = N_Object_Declaration |
| and then Nkind (Expression (Parent (Entity (Expr)))) = N_Allocator |
| then |
| Build_Allocate_Deallocate_Proc (Parent (Entity (Expr)), True); |
| return; |
| end if; |
| |
| -- The allocator may have been rewritten into something else in which |
| -- case the expansion performed by this routine does not apply. |
| |
| if Nkind (Expr) /= N_Allocator then |
| return; |
| end if; |
| |
| Ptr_Typ := Base_Type (Etype (Expr)); |
| Proc_To_Call := Procedure_To_Call (Expr); |
| end if; |
| |
| Pool_Id := Associated_Storage_Pool (Ptr_Typ); |
| Desig_Typ := Available_View (Designated_Type (Ptr_Typ)); |
| |
| -- Handle concurrent types |
| |
| if Is_Concurrent_Type (Desig_Typ) |
| and then Present (Corresponding_Record_Type (Desig_Typ)) |
| then |
| Desig_Typ := Corresponding_Record_Type (Desig_Typ); |
| end if; |
| |
| -- Do not process allocations / deallocations without a pool |
| |
| if No (Pool_Id) then |
| return; |
| |
| -- Do not process allocations on / deallocations from the secondary |
| -- stack. |
| |
| elsif Is_RTE (Pool_Id, RE_SS_Pool) then |
| return; |
| |
| -- Do not replicate the machinery if the allocator / free has already |
| -- been expanded and has a custom Allocate / Deallocate. |
| |
| elsif Present (Proc_To_Call) |
| and then Is_Allocate_Deallocate_Proc (Proc_To_Call) |
| then |
| return; |
| end if; |
| |
| if Needs_Finalization (Desig_Typ) then |
| |
| -- Certain run-time configurations and targets do not provide support |
| -- for controlled types. |
| |
| if Restriction_Active (No_Finalization) then |
| return; |
| |
| -- Do nothing if the access type may never allocate / deallocate |
| -- objects. |
| |
| elsif No_Pool_Assigned (Ptr_Typ) then |
| return; |
| |
| -- Access-to-controlled types are not supported on .NET/JVM since |
| -- these targets cannot support pools and address arithmetic. |
| |
| elsif VM_Target /= No_VM then |
| return; |
| end if; |
| |
| -- The allocation / deallocation of a controlled object must be |
| -- chained on / detached from a finalization master. |
| |
| pragma Assert (Present (Finalization_Master (Ptr_Typ))); |
| |
| -- The only other kind of allocation / deallocation supported by this |
| -- routine is on / from a subpool. |
| |
| elsif Nkind (Expr) = N_Allocator |
| and then No (Subpool_Handle_Name (Expr)) |
| then |
| return; |
| end if; |
| |
| declare |
| Loc : constant Source_Ptr := Sloc (N); |
| Addr_Id : constant Entity_Id := Make_Temporary (Loc, 'A'); |
| Alig_Id : constant Entity_Id := Make_Temporary (Loc, 'L'); |
| Proc_Id : constant Entity_Id := Make_Temporary (Loc, 'P'); |
| Size_Id : constant Entity_Id := Make_Temporary (Loc, 'S'); |
| |
| Actuals : List_Id; |
| Fin_Addr_Id : Entity_Id; |
| Fin_Mas_Act : Node_Id; |
| Fin_Mas_Id : Entity_Id; |
| Proc_To_Call : Entity_Id; |
| Subpool : Node_Id := Empty; |
| |
| begin |
| -- Step 1: Construct all the actuals for the call to library routine |
| -- Allocate_Any_Controlled / Deallocate_Any_Controlled. |
| |
| -- a) Storage pool |
| |
| Actuals := New_List (New_Reference_To (Pool_Id, Loc)); |
| |
| if Is_Allocate then |
| |
| -- b) Subpool |
| |
| if Nkind (Expr) = N_Allocator then |
| Subpool := Subpool_Handle_Name (Expr); |
| end if; |
| |
| -- If a subpool is present it can be an arbitrary name, so make |
| -- the actual by copying the tree. |
| |
| if Present (Subpool) then |
| Append_To (Actuals, New_Copy_Tree (Subpool, New_Sloc => Loc)); |
| else |
| Append_To (Actuals, Make_Null (Loc)); |
| end if; |
| |
| -- c) Finalization master |
| |
| if Needs_Finalization (Desig_Typ) then |
| Fin_Mas_Id := Finalization_Master (Ptr_Typ); |
| Fin_Mas_Act := New_Reference_To (Fin_Mas_Id, Loc); |
| |
| -- Handle the case where the master is actually a pointer to a |
| -- master. This case arises in build-in-place functions. |
| |
| if Is_Access_Type (Etype (Fin_Mas_Id)) then |
| Append_To (Actuals, Fin_Mas_Act); |
| else |
| Append_To (Actuals, |
| Make_Attribute_Reference (Loc, |
| Prefix => Fin_Mas_Act, |
| Attribute_Name => Name_Unrestricted_Access)); |
| end if; |
| else |
| Append_To (Actuals, Make_Null (Loc)); |
| end if; |
| |
| -- d) Finalize_Address |
| |
| -- Primitive Finalize_Address is never generated in CodePeer mode |
| -- since it contains an Unchecked_Conversion. |
| |
| if Needs_Finalization (Desig_Typ) and then not CodePeer_Mode then |
| Fin_Addr_Id := Find_Finalize_Address (Desig_Typ); |
| pragma Assert (Present (Fin_Addr_Id)); |
| |
| Append_To (Actuals, |
| Make_Attribute_Reference (Loc, |
| Prefix => New_Reference_To (Fin_Addr_Id, Loc), |
| Attribute_Name => Name_Unrestricted_Access)); |
| else |
| Append_To (Actuals, Make_Null (Loc)); |
| end if; |
| end if; |
| |
| -- e) Address |
| -- f) Storage_Size |
| -- g) Alignment |
| |
| Append_To (Actuals, New_Reference_To (Addr_Id, Loc)); |
| Append_To (Actuals, New_Reference_To (Size_Id, Loc)); |
| |
| if Is_Allocate or else not Is_Class_Wide_Type (Desig_Typ) then |
| Append_To (Actuals, New_Reference_To (Alig_Id, Loc)); |
| |
| -- For deallocation of class wide types we obtain the value of |
| -- alignment from the Type Specific Record of the deallocated object. |
| -- This is needed because the frontend expansion of class-wide types |
| -- into equivalent types confuses the backend. |
| |
| else |
| -- Generate: |
| -- Obj.all'Alignment |
| |
| -- ... because 'Alignment applied to class-wide types is expanded |
| -- into the code that reads the value of alignment from the TSD |
| -- (see Expand_N_Attribute_Reference) |
| |
| Append_To (Actuals, |
| Unchecked_Convert_To (RTE (RE_Storage_Offset), |
| Make_Attribute_Reference (Loc, |
| Prefix => |
| Make_Explicit_Dereference (Loc, Relocate_Node (Expr)), |
| Attribute_Name => Name_Alignment))); |
| end if; |
| |
| -- h) Is_Controlled |
| |
| -- Generate a run-time check to determine whether a class-wide object |
| -- is truly controlled. |
| |
| if Needs_Finalization (Desig_Typ) then |
| if Is_Class_Wide_Type (Desig_Typ) |
| or else Is_Generic_Actual_Type (Desig_Typ) |
| then |
| declare |
| Flag_Id : constant Entity_Id := Make_Temporary (Loc, 'F'); |
| Flag_Expr : Node_Id; |
| Param : Node_Id; |
| Temp : Node_Id; |
| |
| begin |
| if Is_Allocate then |
| Temp := Find_Object (Expression (Expr)); |
| else |
| Temp := Expr; |
| end if; |
| |
| -- Processing for generic actuals |
| |
| if Is_Generic_Actual_Type (Desig_Typ) then |
| Flag_Expr := |
| New_Reference_To (Boolean_Literals |
| (Needs_Finalization (Base_Type (Desig_Typ))), Loc); |
| |
| -- Processing for subtype indications |
| |
| elsif Nkind (Temp) in N_Has_Entity |
| and then Is_Type (Entity (Temp)) |
| then |
| Flag_Expr := |
| New_Reference_To (Boolean_Literals |
| (Needs_Finalization (Entity (Temp))), Loc); |
| |
| -- Generate a runtime check to test the controlled state of |
| -- an object for the purposes of allocation / deallocation. |
| |
| else |
| -- The following case arises when allocating through an |
| -- interface class-wide type, generate: |
| -- |
| -- Temp.all |
| |
| if Is_RTE (Etype (Temp), RE_Tag_Ptr) then |
| Param := |
| Make_Explicit_Dereference (Loc, |
| Prefix => |
| Relocate_Node (Temp)); |
| |
| -- Generate: |
| -- Temp'Tag |
| |
| else |
| Param := |
| Make_Attribute_Reference (Loc, |
| Prefix => |
| Relocate_Node (Temp), |
| Attribute_Name => Name_Tag); |
| end if; |
| |
| -- Generate: |
| -- Needs_Finalization (<Param>) |
| |
| Flag_Expr := |
| Make_Function_Call (Loc, |
| Name => |
| New_Reference_To (RTE (RE_Needs_Finalization), Loc), |
| Parameter_Associations => New_List (Param)); |
| end if; |
| |
| -- Create the temporary which represents the finalization |
| -- state of the expression. Generate: |
| -- |
| -- F : constant Boolean := <Flag_Expr>; |
| |
| Insert_Action (N, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Flag_Id, |
| Constant_Present => True, |
| Object_Definition => |
| New_Reference_To (Standard_Boolean, Loc), |
| Expression => Flag_Expr)); |
| |
| -- The flag acts as the last actual |
| |
| Append_To (Actuals, New_Reference_To (Flag_Id, Loc)); |
| end; |
| |
| -- The object is statically known to be controlled |
| |
| else |
| Append_To (Actuals, New_Reference_To (Standard_True, Loc)); |
| end if; |
| |
| else |
| Append_To (Actuals, New_Reference_To (Standard_False, Loc)); |
| end if; |
| |
| -- i) On_Subpool |
| |
| if Is_Allocate then |
| Append_To (Actuals, |
| New_Reference_To (Boolean_Literals (Present (Subpool)), Loc)); |
| end if; |
| |
| -- Step 2: Build a wrapper Allocate / Deallocate which internally |
| -- calls Allocate_Any_Controlled / Deallocate_Any_Controlled. |
| |
| -- Select the proper routine to call |
| |
| if Is_Allocate then |
| Proc_To_Call := RTE (RE_Allocate_Any_Controlled); |
| else |
| Proc_To_Call := RTE (RE_Deallocate_Any_Controlled); |
| end if; |
| |
| -- Create a custom Allocate / Deallocate routine which has identical |
| -- profile to that of System.Storage_Pools. |
| |
| Insert_Action (N, |
| Make_Subprogram_Body (Loc, |
| Specification => |
| |
| -- procedure Pnn |
| |
| Make_Procedure_Specification (Loc, |
| Defining_Unit_Name => Proc_Id, |
| Parameter_Specifications => New_List ( |
| |
| -- P : Root_Storage_Pool |
| |
| Make_Parameter_Specification (Loc, |
| Defining_Identifier => Make_Temporary (Loc, 'P'), |
| Parameter_Type => |
| New_Reference_To (RTE (RE_Root_Storage_Pool), Loc)), |
| |
| -- A : [out] Address |
| |
| Make_Parameter_Specification (Loc, |
| Defining_Identifier => Addr_Id, |
| Out_Present => Is_Allocate, |
| Parameter_Type => |
| New_Reference_To (RTE (RE_Address), Loc)), |
| |
| -- S : Storage_Count |
| |
| Make_Parameter_Specification (Loc, |
| Defining_Identifier => Size_Id, |
| Parameter_Type => |
| New_Reference_To (RTE (RE_Storage_Count), Loc)), |
| |
| -- L : Storage_Count |
| |
| Make_Parameter_Specification (Loc, |
| Defining_Identifier => Alig_Id, |
| Parameter_Type => |
| New_Reference_To (RTE (RE_Storage_Count), Loc)))), |
| |
| Declarations => No_List, |
| |
| Handled_Statement_Sequence => |
| Make_Handled_Sequence_Of_Statements (Loc, |
| Statements => New_List ( |
| Make_Procedure_Call_Statement (Loc, |
| Name => New_Reference_To (Proc_To_Call, Loc), |
| Parameter_Associations => Actuals))))); |
| |
| -- The newly generated Allocate / Deallocate becomes the default |
| -- procedure to call when the back end processes the allocation / |
| -- deallocation. |
| |
| if Is_Allocate then |
| Set_Procedure_To_Call (Expr, Proc_Id); |
| else |
| Set_Procedure_To_Call (N, Proc_Id); |
| end if; |
| end; |
| end Build_Allocate_Deallocate_Proc; |
| |
| ------------------------ |
| -- Build_Runtime_Call -- |
| ------------------------ |
| |
| function Build_Runtime_Call (Loc : Source_Ptr; RE : RE_Id) return Node_Id is |
| begin |
| -- If entity is not available, we can skip making the call (this avoids |
| -- junk duplicated error messages in a number of cases). |
| |
| if not RTE_Available (RE) then |
| return Make_Null_Statement (Loc); |
| else |
| return |
| Make_Procedure_Call_Statement (Loc, |
| Name => New_Reference_To (RTE (RE), Loc)); |
| end if; |
| end Build_Runtime_Call; |
| |
| ---------------------------- |
| -- Build_Task_Array_Image -- |
| ---------------------------- |
| |
| -- This function generates the body for a function that constructs the |
| -- image string for a task that is an array component. The function is |
| -- local to the init proc for the array type, and is called for each one |
| -- of the components. The constructed image has the form of an indexed |
| -- component, whose prefix is the outer variable of the array type. |
| -- The n-dimensional array type has known indexes Index, Index2... |
| |
| -- Id_Ref is an indexed component form created by the enclosing init proc. |
| -- Its successive indexes are Val1, Val2, ... which are the loop variables |
| -- in the loops that call the individual task init proc on each component. |
| |
| -- The generated function has the following structure: |
| |
| -- function F return String is |
| -- Pref : string renames Task_Name; |
| -- T1 : String := Index1'Image (Val1); |
| -- ... |
| -- Tn : String := indexn'image (Valn); |
| -- Len : Integer := T1'Length + ... + Tn'Length + n + 1; |
| -- -- Len includes commas and the end parentheses. |
| -- Res : String (1..Len); |
| -- Pos : Integer := Pref'Length; |
| -- |
| -- begin |
| -- Res (1 .. Pos) := Pref; |
| -- Pos := Pos + 1; |
| -- Res (Pos) := '('; |
| -- Pos := Pos + 1; |
| -- Res (Pos .. Pos + T1'Length - 1) := T1; |
| -- Pos := Pos + T1'Length; |
| -- Res (Pos) := '.'; |
| -- Pos := Pos + 1; |
| -- ... |
| -- Res (Pos .. Pos + Tn'Length - 1) := Tn; |
| -- Res (Len) := ')'; |
| -- |
| -- return Res; |
| -- end F; |
| -- |
| -- Needless to say, multidimensional arrays of tasks are rare enough that |
| -- the bulkiness of this code is not really a concern. |
| |
| function Build_Task_Array_Image |
| (Loc : Source_Ptr; |
| Id_Ref : Node_Id; |
| A_Type : Entity_Id; |
| Dyn : Boolean := False) return Node_Id |
| is |
| Dims : constant Nat := Number_Dimensions (A_Type); |
| -- Number of dimensions for array of tasks |
| |
| Temps : array (1 .. Dims) of Entity_Id; |
| -- Array of temporaries to hold string for each index |
| |
| Indx : Node_Id; |
| -- Index expression |
| |
| Len : Entity_Id; |
| -- Total length of generated name |
| |
| Pos : Entity_Id; |
| -- Running index for substring assignments |
| |
| Pref : constant Entity_Id := Make_Temporary (Loc, 'P'); |
| -- Name of enclosing variable, prefix of resulting name |
| |
| Res : Entity_Id; |
| -- String to hold result |
| |
| Val : Node_Id; |
| -- Value of successive indexes |
| |
| Sum : Node_Id; |
| -- Expression to compute total size of string |
| |
| T : Entity_Id; |
| -- Entity for name at one index position |
| |
| Decls : constant List_Id := New_List; |
| Stats : constant List_Id := New_List; |
| |
| begin |
| -- For a dynamic task, the name comes from the target variable. For a |
| -- static one it is a formal of the enclosing init proc. |
| |
| if Dyn then |
| Get_Name_String (Chars (Entity (Prefix (Id_Ref)))); |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Pref, |
| Object_Definition => New_Occurrence_Of (Standard_String, Loc), |
| Expression => |
| Make_String_Literal (Loc, |
| Strval => String_From_Name_Buffer))); |
| |
| else |
| Append_To (Decls, |
| Make_Object_Renaming_Declaration (Loc, |
| Defining_Identifier => Pref, |
| Subtype_Mark => New_Occurrence_Of (Standard_String, Loc), |
| Name => Make_Identifier (Loc, Name_uTask_Name))); |
| end if; |
| |
| Indx := First_Index (A_Type); |
| Val := First (Expressions (Id_Ref)); |
| |
| for J in 1 .. Dims loop |
| T := Make_Temporary (Loc, 'T'); |
| Temps (J) := T; |
| |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => T, |
| Object_Definition => New_Occurrence_Of (Standard_String, Loc), |
| Expression => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Image, |
| Prefix => New_Occurrence_Of (Etype (Indx), Loc), |
| Expressions => New_List (New_Copy_Tree (Val))))); |
| |
| Next_Index (Indx); |
| Next (Val); |
| end loop; |
| |
| Sum := Make_Integer_Literal (Loc, Dims + 1); |
| |
| Sum := |
| Make_Op_Add (Loc, |
| Left_Opnd => Sum, |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => New_Occurrence_Of (Pref, Loc), |
| Expressions => New_List (Make_Integer_Literal (Loc, 1)))); |
| |
| for J in 1 .. Dims loop |
| Sum := |
| Make_Op_Add (Loc, |
| Left_Opnd => Sum, |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => |
| New_Occurrence_Of (Temps (J), Loc), |
| Expressions => New_List (Make_Integer_Literal (Loc, 1)))); |
| end loop; |
| |
| Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats); |
| |
| Set_Character_Literal_Name (Char_Code (Character'Pos ('('))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => |
| Make_Indexed_Component (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Expressions => New_List (New_Occurrence_Of (Pos, Loc))), |
| Expression => |
| Make_Character_Literal (Loc, |
| Chars => Name_Find, |
| Char_Literal_Value => UI_From_Int (Character'Pos ('('))))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Pos, Loc), |
| Expression => |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Occurrence_Of (Pos, Loc), |
| Right_Opnd => Make_Integer_Literal (Loc, 1)))); |
| |
| for J in 1 .. Dims loop |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => |
| Make_Slice (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Discrete_Range => |
| Make_Range (Loc, |
| Low_Bound => New_Occurrence_Of (Pos, Loc), |
| High_Bound => |
| Make_Op_Subtract (Loc, |
| Left_Opnd => |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Occurrence_Of (Pos, Loc), |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => |
| New_Occurrence_Of (Temps (J), Loc), |
| Expressions => |
| New_List (Make_Integer_Literal (Loc, 1)))), |
| Right_Opnd => Make_Integer_Literal (Loc, 1)))), |
| |
| Expression => New_Occurrence_Of (Temps (J), Loc))); |
| |
| if J < Dims then |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Pos, Loc), |
| Expression => |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Occurrence_Of (Pos, Loc), |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => New_Occurrence_Of (Temps (J), Loc), |
| Expressions => |
| New_List (Make_Integer_Literal (Loc, 1)))))); |
| |
| Set_Character_Literal_Name (Char_Code (Character'Pos (','))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => Make_Indexed_Component (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Expressions => New_List (New_Occurrence_Of (Pos, Loc))), |
| Expression => |
| Make_Character_Literal (Loc, |
| Chars => Name_Find, |
| Char_Literal_Value => UI_From_Int (Character'Pos (','))))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Pos, Loc), |
| Expression => |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Occurrence_Of (Pos, Loc), |
| Right_Opnd => Make_Integer_Literal (Loc, 1)))); |
| end if; |
| end loop; |
| |
| Set_Character_Literal_Name (Char_Code (Character'Pos (')'))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => |
| Make_Indexed_Component (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Expressions => New_List (New_Occurrence_Of (Len, Loc))), |
| Expression => |
| Make_Character_Literal (Loc, |
| Chars => Name_Find, |
| Char_Literal_Value => UI_From_Int (Character'Pos (')'))))); |
| return Build_Task_Image_Function (Loc, Decls, Stats, Res); |
| end Build_Task_Array_Image; |
| |
| ---------------------------- |
| -- Build_Task_Image_Decls -- |
| ---------------------------- |
| |
| function Build_Task_Image_Decls |
| (Loc : Source_Ptr; |
| Id_Ref : Node_Id; |
| A_Type : Entity_Id; |
| In_Init_Proc : Boolean := False) return List_Id |
| is |
| Decls : constant List_Id := New_List; |
| T_Id : Entity_Id := Empty; |
| Decl : Node_Id; |
| Expr : Node_Id := Empty; |
| Fun : Node_Id := Empty; |
| Is_Dyn : constant Boolean := |
| Nkind (Parent (Id_Ref)) = N_Assignment_Statement |
| and then |
| Nkind (Expression (Parent (Id_Ref))) = N_Allocator; |
| |
| begin |
| -- If Discard_Names or No_Implicit_Heap_Allocations are in effect, |
| -- generate a dummy declaration only. |
| |
| if Restriction_Active (No_Implicit_Heap_Allocations) |
| or else Global_Discard_Names |
| then |
| T_Id := Make_Temporary (Loc, 'J'); |
| Name_Len := 0; |
| |
| return |
| New_List ( |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => T_Id, |
| Object_Definition => New_Occurrence_Of (Standard_String, Loc), |
| Expression => |
| Make_String_Literal (Loc, |
| Strval => String_From_Name_Buffer))); |
| |
| else |
| if Nkind (Id_Ref) = N_Identifier |
| or else Nkind (Id_Ref) = N_Defining_Identifier |
| then |
| -- For a simple variable, the image of the task is built from |
| -- the name of the variable. To avoid possible conflict with the |
| -- anonymous type created for a single protected object, add a |
| -- numeric suffix. |
| |
| T_Id := |
| Make_Defining_Identifier (Loc, |
| New_External_Name (Chars (Id_Ref), 'T', 1)); |
| |
| Get_Name_String (Chars (Id_Ref)); |
| |
| Expr := |
| Make_String_Literal (Loc, |
| Strval => String_From_Name_Buffer); |
| |
| elsif Nkind (Id_Ref) = N_Selected_Component then |
| T_Id := |
| Make_Defining_Identifier (Loc, |
| New_External_Name (Chars (Selector_Name (Id_Ref)), 'T')); |
| Fun := Build_Task_Record_Image (Loc, Id_Ref, Is_Dyn); |
| |
| elsif Nkind (Id_Ref) = N_Indexed_Component then |
| T_Id := |
| Make_Defining_Identifier (Loc, |
| New_External_Name (Chars (A_Type), 'N')); |
| |
| Fun := Build_Task_Array_Image (Loc, Id_Ref, A_Type, Is_Dyn); |
| end if; |
| end if; |
| |
| if Present (Fun) then |
| Append (Fun, Decls); |
| Expr := Make_Function_Call (Loc, |
| Name => New_Occurrence_Of (Defining_Entity (Fun), Loc)); |
| |
| if not In_Init_Proc and then VM_Target = No_VM then |
| Set_Uses_Sec_Stack (Defining_Entity (Fun)); |
| end if; |
| end if; |
| |
| Decl := Make_Object_Declaration (Loc, |
| Defining_Identifier => T_Id, |
| Object_Definition => New_Occurrence_Of (Standard_String, Loc), |
| Constant_Present => True, |
| Expression => Expr); |
| |
| Append (Decl, Decls); |
| return Decls; |
| end Build_Task_Image_Decls; |
| |
| ------------------------------- |
| -- Build_Task_Image_Function -- |
| ------------------------------- |
| |
| function Build_Task_Image_Function |
| (Loc : Source_Ptr; |
| Decls : List_Id; |
| Stats : List_Id; |
| Res : Entity_Id) return Node_Id |
| is |
| Spec : Node_Id; |
| |
| begin |
| Append_To (Stats, |
| Make_Simple_Return_Statement (Loc, |
| Expression => New_Occurrence_Of (Res, Loc))); |
| |
| Spec := Make_Function_Specification (Loc, |
| Defining_Unit_Name => Make_Temporary (Loc, 'F'), |
| Result_Definition => New_Occurrence_Of (Standard_String, Loc)); |
| |
| -- Calls to 'Image use the secondary stack, which must be cleaned up |
| -- after the task name is built. |
| |
| return Make_Subprogram_Body (Loc, |
| Specification => Spec, |
| Declarations => Decls, |
| Handled_Statement_Sequence => |
| Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats)); |
| end Build_Task_Image_Function; |
| |
| ----------------------------- |
| -- Build_Task_Image_Prefix -- |
| ----------------------------- |
| |
| procedure Build_Task_Image_Prefix |
| (Loc : Source_Ptr; |
| Len : out Entity_Id; |
| Res : out Entity_Id; |
| Pos : out Entity_Id; |
| Prefix : Entity_Id; |
| Sum : Node_Id; |
| Decls : List_Id; |
| Stats : List_Id) |
| is |
| begin |
| Len := Make_Temporary (Loc, 'L', Sum); |
| |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Len, |
| Object_Definition => New_Occurrence_Of (Standard_Integer, Loc), |
| Expression => Sum)); |
| |
| Res := Make_Temporary (Loc, 'R'); |
| |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Res, |
| Object_Definition => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Occurrence_Of (Standard_String, Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint (Loc, |
| Constraints => |
| New_List ( |
| Make_Range (Loc, |
| Low_Bound => Make_Integer_Literal (Loc, 1), |
| High_Bound => New_Occurrence_Of (Len, Loc))))))); |
| |
| Pos := Make_Temporary (Loc, 'P'); |
| |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Pos, |
| Object_Definition => New_Occurrence_Of (Standard_Integer, Loc))); |
| |
| -- Pos := Prefix'Length; |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Pos, Loc), |
| Expression => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => New_Occurrence_Of (Prefix, Loc), |
| Expressions => New_List (Make_Integer_Literal (Loc, 1))))); |
| |
| -- Res (1 .. Pos) := Prefix; |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => |
| Make_Slice (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Discrete_Range => |
| Make_Range (Loc, |
| Low_Bound => Make_Integer_Literal (Loc, 1), |
| High_Bound => New_Occurrence_Of (Pos, Loc))), |
| |
| Expression => New_Occurrence_Of (Prefix, Loc))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Pos, Loc), |
| Expression => |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Occurrence_Of (Pos, Loc), |
| Right_Opnd => Make_Integer_Literal (Loc, 1)))); |
| end Build_Task_Image_Prefix; |
| |
| ----------------------------- |
| -- Build_Task_Record_Image -- |
| ----------------------------- |
| |
| function Build_Task_Record_Image |
| (Loc : Source_Ptr; |
| Id_Ref : Node_Id; |
| Dyn : Boolean := False) return Node_Id |
| is |
| Len : Entity_Id; |
| -- Total length of generated name |
| |
| Pos : Entity_Id; |
| -- Index into result |
| |
| Res : Entity_Id; |
| -- String to hold result |
| |
| Pref : constant Entity_Id := Make_Temporary (Loc, 'P'); |
| -- Name of enclosing variable, prefix of resulting name |
| |
| Sum : Node_Id; |
| -- Expression to compute total size of string |
| |
| Sel : Entity_Id; |
| -- Entity for selector name |
| |
| Decls : constant List_Id := New_List; |
| Stats : constant List_Id := New_List; |
| |
| begin |
| -- For a dynamic task, the name comes from the target variable. For a |
| -- static one it is a formal of the enclosing init proc. |
| |
| if Dyn then |
| Get_Name_String (Chars (Entity (Prefix (Id_Ref)))); |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Pref, |
| Object_Definition => New_Occurrence_Of (Standard_String, Loc), |
| Expression => |
| Make_String_Literal (Loc, |
| Strval => String_From_Name_Buffer))); |
| |
| else |
| Append_To (Decls, |
| Make_Object_Renaming_Declaration (Loc, |
| Defining_Identifier => Pref, |
| Subtype_Mark => New_Occurrence_Of (Standard_String, Loc), |
| Name => Make_Identifier (Loc, Name_uTask_Name))); |
| end if; |
| |
| Sel := Make_Temporary (Loc, 'S'); |
| |
| Get_Name_String (Chars (Selector_Name (Id_Ref))); |
| |
| Append_To (Decls, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Sel, |
| Object_Definition => New_Occurrence_Of (Standard_String, Loc), |
| Expression => |
| Make_String_Literal (Loc, |
| Strval => String_From_Name_Buffer))); |
| |
| Sum := Make_Integer_Literal (Loc, Nat (Name_Len + 1)); |
| |
| Sum := |
| Make_Op_Add (Loc, |
| Left_Opnd => Sum, |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => |
| New_Occurrence_Of (Pref, Loc), |
| Expressions => New_List (Make_Integer_Literal (Loc, 1)))); |
| |
| Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats); |
| |
| Set_Character_Literal_Name (Char_Code (Character'Pos ('.'))); |
| |
| -- Res (Pos) := '.'; |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => Make_Indexed_Component (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Expressions => New_List (New_Occurrence_Of (Pos, Loc))), |
| Expression => |
| Make_Character_Literal (Loc, |
| Chars => Name_Find, |
| Char_Literal_Value => |
| UI_From_Int (Character'Pos ('.'))))); |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Pos, Loc), |
| Expression => |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Occurrence_Of (Pos, Loc), |
| Right_Opnd => Make_Integer_Literal (Loc, 1)))); |
| |
| -- Res (Pos .. Len) := Selector; |
| |
| Append_To (Stats, |
| Make_Assignment_Statement (Loc, |
| Name => Make_Slice (Loc, |
| Prefix => New_Occurrence_Of (Res, Loc), |
| Discrete_Range => |
| Make_Range (Loc, |
| Low_Bound => New_Occurrence_Of (Pos, Loc), |
| High_Bound => New_Occurrence_Of (Len, Loc))), |
| Expression => New_Occurrence_Of (Sel, Loc))); |
| |
| return Build_Task_Image_Function (Loc, Decls, Stats, Res); |
| end Build_Task_Record_Image; |
| |
| ---------------------------------- |
| -- Component_May_Be_Bit_Aligned -- |
| ---------------------------------- |
| |
| function Component_May_Be_Bit_Aligned (Comp : Entity_Id) return Boolean is |
| UT : Entity_Id; |
| |
| begin |
| -- If no component clause, then everything is fine, since the back end |
| -- never bit-misaligns by default, even if there is a pragma Packed for |
| -- the record. |
| |
| if No (Comp) or else No (Component_Clause (Comp)) then |
| return False; |
| end if; |
| |
| UT := Underlying_Type (Etype (Comp)); |
| |
| -- It is only array and record types that cause trouble |
| |
| if not Is_Record_Type (UT) and then not Is_Array_Type (UT) then |
| return False; |
| |
| -- If we know that we have a small (64 bits or less) record or small |
| -- bit-packed array, then everything is fine, since the back end can |
| -- handle these cases correctly. |
| |
| elsif Esize (Comp) <= 64 |
| and then (Is_Record_Type (UT) or else Is_Bit_Packed_Array (UT)) |
| then |
| return False; |
| |
| -- Otherwise if the component is not byte aligned, we know we have the |
| -- nasty unaligned case. |
| |
| elsif Normalized_First_Bit (Comp) /= Uint_0 |
| or else Esize (Comp) mod System_Storage_Unit /= Uint_0 |
| then |
| return True; |
| |
| -- If we are large and byte aligned, then OK at this level |
| |
| else |
| return False; |
| end if; |
| end Component_May_Be_Bit_Aligned; |
| |
| ----------------------------------- |
| -- Corresponding_Runtime_Package -- |
| ----------------------------------- |
| |
| function Corresponding_Runtime_Package (Typ : Entity_Id) return RTU_Id is |
| Pkg_Id : RTU_Id := RTU_Null; |
| |
| begin |
| pragma Assert (Is_Concurrent_Type (Typ)); |
| |
| if Ekind (Typ) in Protected_Kind then |
| if Has_Entries (Typ) |
| |
| -- A protected type without entries that covers an interface and |
| -- overrides the abstract routines with protected procedures is |
| -- considered equivalent to a protected type with entries in the |
| -- context of dispatching select statements. It is sufficient to |
| -- check for the presence of an interface list in the declaration |
| -- node to recognize this case. |
| |
| or else Present (Interface_List (Parent (Typ))) |
| or else |
| (((Has_Attach_Handler (Typ) and then not Restricted_Profile) |
| or else Has_Interrupt_Handler (Typ)) |
| and then not Restriction_Active (No_Dynamic_Attachment)) |
| then |
| if Abort_Allowed |
| or else Restriction_Active (No_Entry_Queue) = False |
| or else Number_Entries (Typ) > 1 |
| or else (Has_Attach_Handler (Typ) |
| and then not Restricted_Profile) |
| then |
| Pkg_Id := System_Tasking_Protected_Objects_Entries; |
| else |
| Pkg_Id := System_Tasking_Protected_Objects_Single_Entry; |
| end if; |
| |
| else |
| Pkg_Id := System_Tasking_Protected_Objects; |
| end if; |
| end if; |
| |
| return Pkg_Id; |
| end Corresponding_Runtime_Package; |
| |
| ------------------------------- |
| -- Convert_To_Actual_Subtype -- |
| ------------------------------- |
| |
| procedure Convert_To_Actual_Subtype (Exp : Entity_Id) is |
| Act_ST : Entity_Id; |
| |
| begin |
| Act_ST := Get_Actual_Subtype (Exp); |
| |
| if Act_ST = Etype (Exp) then |
| return; |
| else |
| Rewrite (Exp, Convert_To (Act_ST, Relocate_Node (Exp))); |
| Analyze_And_Resolve (Exp, Act_ST); |
| end if; |
| end Convert_To_Actual_Subtype; |
| |
| ----------------------------------- |
| -- Current_Sem_Unit_Declarations -- |
| ----------------------------------- |
| |
| function Current_Sem_Unit_Declarations return List_Id is |
| U : Node_Id := Unit (Cunit (Current_Sem_Unit)); |
| Decls : List_Id; |
| |
| begin |
| -- If the current unit is a package body, locate the visible |
| -- declarations of the package spec. |
| |
| if Nkind (U) = N_Package_Body then |
| U := Unit (Library_Unit (Cunit (Current_Sem_Unit))); |
| end if; |
| |
| if Nkind (U) = N_Package_Declaration then |
| U := Specification (U); |
| Decls := Visible_Declarations (U); |
| |
| if No (Decls) then |
| Decls := New_List; |
| Set_Visible_Declarations (U, Decls); |
| end if; |
| |
| else |
| Decls := Declarations (U); |
| |
| if No (Decls) then |
| Decls := New_List; |
| Set_Declarations (U, Decls); |
| end if; |
| end if; |
| |
| return Decls; |
| end Current_Sem_Unit_Declarations; |
| |
| ----------------------- |
| -- Duplicate_Subexpr -- |
| ----------------------- |
| |
| function Duplicate_Subexpr |
| (Exp : Node_Id; |
| Name_Req : Boolean := False) return Node_Id |
| is |
| begin |
| Remove_Side_Effects (Exp, Name_Req); |
| return New_Copy_Tree (Exp); |
| end Duplicate_Subexpr; |
| |
| --------------------------------- |
| -- Duplicate_Subexpr_No_Checks -- |
| --------------------------------- |
| |
| function Duplicate_Subexpr_No_Checks |
| (Exp : Node_Id; |
| Name_Req : Boolean := False) return Node_Id |
| is |
| New_Exp : Node_Id; |
| begin |
| Remove_Side_Effects (Exp, Name_Req); |
| New_Exp := New_Copy_Tree (Exp); |
| Remove_Checks (New_Exp); |
| return New_Exp; |
| end Duplicate_Subexpr_No_Checks; |
| |
| ----------------------------------- |
| -- Duplicate_Subexpr_Move_Checks -- |
| ----------------------------------- |
| |
| function Duplicate_Subexpr_Move_Checks |
| (Exp : Node_Id; |
| Name_Req : Boolean := False) return Node_Id |
| is |
| New_Exp : Node_Id; |
| begin |
| Remove_Side_Effects (Exp, Name_Req); |
| New_Exp := New_Copy_Tree (Exp); |
| Remove_Checks (Exp); |
| return New_Exp; |
| end Duplicate_Subexpr_Move_Checks; |
| |
| -------------------- |
| -- Ensure_Defined -- |
| -------------------- |
| |
| procedure Ensure_Defined (Typ : Entity_Id; N : Node_Id) is |
| IR : Node_Id; |
| |
| begin |
| -- An itype reference must only be created if this is a local itype, so |
| -- that gigi can elaborate it on the proper objstack. |
| |
| if Is_Itype (Typ) and then Scope (Typ) = Current_Scope then |
| IR := Make_Itype_Reference (Sloc (N)); |
| Set_Itype (IR, Typ); |
| Insert_Action (N, IR); |
| end if; |
| end Ensure_Defined; |
| |
| -------------------- |
| -- Entry_Names_OK -- |
| -------------------- |
| |
| function Entry_Names_OK return Boolean is |
| begin |
| return |
| not Restricted_Profile |
| and then not Global_Discard_Names |
| and then not Restriction_Active (No_Implicit_Heap_Allocations) |
| and then not Restriction_Active (No_Local_Allocators); |
| end Entry_Names_OK; |
| |
| ------------------- |
| -- Evaluate_Name -- |
| ------------------- |
| |
| procedure Evaluate_Name (Nam : Node_Id) is |
| K : constant Node_Kind := Nkind (Nam); |
| |
| begin |
| -- For an explicit dereference, we simply force the evaluation of the |
| -- name expression. The dereference provides a value that is the address |
| -- for the renamed object, and it is precisely this value that we want |
| -- to preserve. |
| |
| if K = N_Explicit_Dereference then |
| Force_Evaluation (Prefix (Nam)); |
| |
| -- For a selected component, we simply evaluate the prefix |
| |
| elsif K = N_Selected_Component then |
| Evaluate_Name (Prefix (Nam)); |
| |
| -- For an indexed component, or an attribute reference, we evaluate the |
| -- prefix, which is itself a name, recursively, and then force the |
| -- evaluation of all the subscripts (or attribute expressions). |
| |
| elsif Nkind_In (K, N_Indexed_Component, N_Attribute_Reference) then |
| Evaluate_Name (Prefix (Nam)); |
| |
| declare |
| E : Node_Id; |
| |
| begin |
| E := First (Expressions (Nam)); |
| while Present (E) loop |
| Force_Evaluation (E); |
| |
| if Original_Node (E) /= E then |
| Set_Do_Range_Check (E, Do_Range_Check (Original_Node (E))); |
| end if; |
| |
| Next (E); |
| end loop; |
| end; |
| |
| -- For a slice, we evaluate the prefix, as for the indexed component |
| -- case and then, if there is a range present, either directly or as the |
| -- constraint of a discrete subtype indication, we evaluate the two |
| -- bounds of this range. |
| |
| elsif K = N_Slice then |
| Evaluate_Name (Prefix (Nam)); |
| |
| declare |
| DR : constant Node_Id := Discrete_Range (Nam); |
| Constr : Node_Id; |
| Rexpr : Node_Id; |
| |
| begin |
| if Nkind (DR) = N_Range then |
| Force_Evaluation (Low_Bound (DR)); |
| Force_Evaluation (High_Bound (DR)); |
| |
| elsif Nkind (DR) = N_Subtype_Indication then |
| Constr := Constraint (DR); |
| |
| if Nkind (Constr) = N_Range_Constraint then |
| Rexpr := Range_Expression (Constr); |
| |
| Force_Evaluation (Low_Bound (Rexpr)); |
| Force_Evaluation (High_Bound (Rexpr)); |
| end if; |
| end if; |
| end; |
| |
| -- For a type conversion, the expression of the conversion must be the |
| -- name of an object, and we simply need to evaluate this name. |
| |
| elsif K = N_Type_Conversion then |
| Evaluate_Name (Expression (Nam)); |
| |
| -- For a function call, we evaluate the call |
| |
| elsif K = N_Function_Call then |
| Force_Evaluation (Nam); |
| |
| -- The remaining cases are direct name, operator symbol and character |
| -- literal. In all these cases, we do nothing, since we want to |
| -- reevaluate each time the renamed object is used. |
| |
| else |
| return; |
| end if; |
| end Evaluate_Name; |
| |
| --------------------- |
| -- Evolve_And_Then -- |
| --------------------- |
| |
| procedure Evolve_And_Then (Cond : in out Node_Id; Cond1 : Node_Id) is |
| begin |
| if No (Cond) then |
| Cond := Cond1; |
| else |
| Cond := |
| Make_And_Then (Sloc (Cond1), |
| Left_Opnd => Cond, |
| Right_Opnd => Cond1); |
| end if; |
| end Evolve_And_Then; |
| |
| -------------------- |
| -- Evolve_Or_Else -- |
| -------------------- |
| |
| procedure Evolve_Or_Else (Cond : in out Node_Id; Cond1 : Node_Id) is |
| begin |
| if No (Cond) then |
| Cond := Cond1; |
| else |
| Cond := |
| Make_Or_Else (Sloc (Cond1), |
| Left_Opnd => Cond, |
| Right_Opnd => Cond1); |
| end if; |
| end Evolve_Or_Else; |
| |
| ------------------------------ |
| -- Expand_Subtype_From_Expr -- |
| ------------------------------ |
| |
| -- This function is applicable for both static and dynamic allocation of |
| -- objects which are constrained by an initial expression. Basically it |
| -- transforms an unconstrained subtype indication into a constrained one. |
| |
| -- The expression may also be transformed in certain cases in order to |
| -- avoid multiple evaluation. In the static allocation case, the general |
| -- scheme is: |
| |
| -- Val : T := Expr; |
| |
| -- is transformed into |
| |
| -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr; |
| -- |
| -- Here are the main cases : |
| -- |
| -- <if Expr is a Slice> |
| -- Val : T ([Index_Subtype (Expr)]) := Expr; |
| -- |
| -- <elsif Expr is a String Literal> |
| -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr; |
| -- |
| -- <elsif Expr is Constrained> |
| -- subtype T is Type_Of_Expr |
| -- Val : T := Expr; |
| -- |
| -- <elsif Expr is an entity_name> |
| -- Val : T (constraints taken from Expr) := Expr; |
| -- |
| -- <else> |
| -- type Axxx is access all T; |
| -- Rval : Axxx := Expr'ref; |
| -- Val : T (constraints taken from Rval) := Rval.all; |
| |
| -- ??? note: when the Expression is allocated in the secondary stack |
| -- we could use it directly instead of copying it by declaring |
| -- Val : T (...) renames Rval.all |
| |
| procedure Expand_Subtype_From_Expr |
| (N : Node_Id; |
| Unc_Type : Entity_Id; |
| Subtype_Indic : Node_Id; |
| Exp : Node_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (N); |
| Exp_Typ : constant Entity_Id := Etype (Exp); |
| T : Entity_Id; |
| |
| begin |
| -- In general we cannot build the subtype if expansion is disabled, |
| -- because internal entities may not have been defined. However, to |
| -- avoid some cascaded errors, we try to continue when the expression is |
| -- an array (or string), because it is safe to compute the bounds. It is |
| -- in fact required to do so even in a generic context, because there |
| -- may be constants that depend on the bounds of a string literal, both |
| -- standard string types and more generally arrays of characters. |
| |
| if not Expander_Active |
| and then (No (Etype (Exp)) or else not Is_String_Type (Etype (Exp))) |
| then |
| return; |
| end if; |
| |
| if Nkind (Exp) = N_Slice then |
| declare |
| Slice_Type : constant Entity_Id := Etype (First_Index (Exp_Typ)); |
| |
| begin |
| Rewrite (Subtype_Indic, |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (Unc_Type, Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint (Loc, |
| Constraints => New_List |
| (New_Reference_To (Slice_Type, Loc))))); |
| |
| -- This subtype indication may be used later for constraint checks |
| -- we better make sure that if a variable was used as a bound of |
| -- of the original slice, its value is frozen. |
| |
| Force_Evaluation (Low_Bound (Scalar_Range (Slice_Type))); |
| Force_Evaluation (High_Bound (Scalar_Range (Slice_Type))); |
| end; |
| |
| elsif Ekind (Exp_Typ) = E_String_Literal_Subtype then |
| Rewrite (Subtype_Indic, |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (Unc_Type, Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint (Loc, |
| Constraints => New_List ( |
| Make_Literal_Range (Loc, |
| Literal_Typ => Exp_Typ))))); |
| |
| elsif Is_Constrained (Exp_Typ) |
| and then not Is_Class_Wide_Type (Unc_Type) |
| then |
| if Is_Itype (Exp_Typ) then |
| |
| -- Within an initialization procedure, a selected component |
| -- denotes a component of the enclosing record, and it appears as |
| -- an actual in a call to its own initialization procedure. If |
| -- this component depends on the outer discriminant, we must |
| -- generate the proper actual subtype for it. |
| |
| if Nkind (Exp) = N_Selected_Component |
| and then Within_Init_Proc |
| then |
| declare |
| Decl : constant Node_Id := |
| Build_Actual_Subtype_Of_Component (Exp_Typ, Exp); |
| begin |
| if Present (Decl) then |
| Insert_Action (N, Decl); |
| T := Defining_Identifier (Decl); |
| else |
| T := Exp_Typ; |
| end if; |
| end; |
| |
| -- No need to generate a new one (new what???) |
| |
| else |
| T := Exp_Typ; |
| end if; |
| |
| else |
| T := Make_Temporary (Loc, 'T'); |
| |
| Insert_Action (N, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => T, |
| Subtype_Indication => New_Reference_To (Exp_Typ, Loc))); |
| |
| -- This type is marked as an itype even though it has an explicit |
| -- declaration since otherwise Is_Generic_Actual_Type can get |
| -- set, resulting in the generation of spurious errors. (See |
| -- sem_ch8.Analyze_Package_Renaming and sem_type.covers) |
| |
| Set_Is_Itype (T); |
| Set_Associated_Node_For_Itype (T, Exp); |
| end if; |
| |
| Rewrite (Subtype_Indic, New_Reference_To (T, Loc)); |
| |
| -- Nothing needs to be done for private types with unknown discriminants |
| -- if the underlying type is not an unconstrained composite type or it |
| -- is an unchecked union. |
| |
| elsif Is_Private_Type (Unc_Type) |
| and then Has_Unknown_Discriminants (Unc_Type) |
| and then (not Is_Composite_Type (Underlying_Type (Unc_Type)) |
| or else Is_Constrained (Underlying_Type (Unc_Type)) |
| or else Is_Unchecked_Union (Underlying_Type (Unc_Type))) |
| then |
| null; |
| |
| -- Case of derived type with unknown discriminants where the parent type |
| -- also has unknown discriminants. |
| |
| elsif Is_Record_Type (Unc_Type) |
| and then not Is_Class_Wide_Type (Unc_Type) |
| and then Has_Unknown_Discriminants (Unc_Type) |
| and then Has_Unknown_Discriminants (Underlying_Type (Unc_Type)) |
| then |
| -- Nothing to be done if no underlying record view available |
| |
| if No (Underlying_Record_View (Unc_Type)) then |
| null; |
| |
| -- Otherwise use the Underlying_Record_View to create the proper |
| -- constrained subtype for an object of a derived type with unknown |
| -- discriminants. |
| |
| else |
| Remove_Side_Effects (Exp); |
| Rewrite (Subtype_Indic, |
| Make_Subtype_From_Expr (Exp, Underlying_Record_View (Unc_Type))); |
| end if; |
| |
| -- Renamings of class-wide interface types require no equivalent |
| -- constrained type declarations because we only need to reference |
| -- the tag component associated with the interface. The same is |
| -- presumably true for class-wide types in general, so this test |
| -- is broadened to include all class-wide renamings, which also |
| -- avoids cases of unbounded recursion in Remove_Side_Effects. |
| -- (Is this really correct, or are there some cases of class-wide |
| -- renamings that require action in this procedure???) |
| |
| elsif Present (N) |
| and then Nkind (N) = N_Object_Renaming_Declaration |
| and then Is_Class_Wide_Type (Unc_Type) |
| then |
| null; |
| |
| -- In Ada 95 nothing to be done if the type of the expression is limited |
| -- because in this case the expression cannot be copied, and its use can |
| -- only be by reference. |
| |
| -- In Ada 2005 the context can be an object declaration whose expression |
| -- is a function that returns in place. If the nominal subtype has |
| -- unknown discriminants, the call still provides constraints on the |
| -- object, and we have to create an actual subtype from it. |
| |
| -- If the type is class-wide, the expression is dynamically tagged and |
| -- we do not create an actual subtype either. Ditto for an interface. |
| -- For now this applies only if the type is immutably limited, and the |
| -- function being called is build-in-place. This will have to be revised |
| -- when build-in-place functions are generalized to other types. |
| |
| elsif Is_Immutably_Limited_Type (Exp_Typ) |
| and then |
| (Is_Class_Wide_Type (Exp_Typ) |
| or else Is_Interface (Exp_Typ) |
| or else not Has_Unknown_Discriminants (Exp_Typ) |
| or else not Is_Composite_Type (Unc_Type)) |
| then |
| null; |
| |
| -- For limited objects initialized with build in place function calls, |
| -- nothing to be done; otherwise we prematurely introduce an N_Reference |
| -- node in the expression initializing the object, which breaks the |
| -- circuitry that detects and adds the additional arguments to the |
| -- called function. |
| |
| elsif Is_Build_In_Place_Function_Call (Exp) then |
| null; |
| |
| else |
| Remove_Side_Effects (Exp); |
| Rewrite (Subtype_Indic, |
| Make_Subtype_From_Expr (Exp, Unc_Type)); |
| end if; |
| end Expand_Subtype_From_Expr; |
| |
| ------------------------ |
| -- Find_Interface_ADT -- |
| ------------------------ |
| |
| function Find_Interface_ADT |
| (T : Entity_Id; |
| Iface : Entity_Id) return Elmt_Id |
| is |
| ADT : Elmt_Id; |
| Typ : Entity_Id := T; |
| |
| begin |
| pragma Assert (Is_Interface (Iface)); |
| |
| -- Handle private types |
| |
| if Has_Private_Declaration (Typ) and then Present (Full_View (Typ)) then |
| Typ := Full_View (Typ); |
| end if; |
| |
| -- Handle access types |
| |
| if Is_Access_Type (Typ) then |
| Typ := Designated_Type (Typ); |
| end if; |
| |
| -- Handle task and protected types implementing interfaces |
| |
| if Is_Concurrent_Type (Typ) then |
| Typ := Corresponding_Record_Type (Typ); |
| end if; |
| |
| pragma Assert |
| (not Is_Class_Wide_Type (Typ) |
| and then Ekind (Typ) /= E_Incomplete_Type); |
| |
| if Is_Ancestor (Iface, Typ, Use_Full_View => True) then |
| return First_Elmt (Access_Disp_Table (Typ)); |
| |
| else |
| ADT := |
| Next_Elmt (Next_Elmt (First_Elmt (Access_Disp_Table (Typ)))); |
| while Present (ADT) |
| and then Present (Related_Type (Node (ADT))) |
| and then Related_Type (Node (ADT)) /= Iface |
| and then not Is_Ancestor (Iface, Related_Type (Node (ADT)), |
| Use_Full_View => True) |
| loop |
| Next_Elmt (ADT); |
| end loop; |
| |
| pragma Assert (Present (Related_Type (Node (ADT)))); |
| return ADT; |
| end if; |
| end Find_Interface_ADT; |
| |
| ------------------------ |
| -- Find_Interface_Tag -- |
| ------------------------ |
| |
| function Find_Interface_Tag |
| (T : Entity_Id; |
| Iface : Entity_Id) return Entity_Id |
| is |
| AI_Tag : Entity_Id; |
| Found : Boolean := False; |
| Typ : Entity_Id := T; |
| |
| procedure Find_Tag (Typ : Entity_Id); |
| -- Internal subprogram used to recursively climb to the ancestors |
| |
| -------------- |
| -- Find_Tag -- |
| -------------- |
| |
| procedure Find_Tag (Typ : Entity_Id) is |
| AI_Elmt : Elmt_Id; |
| AI : Node_Id; |
| |
| begin |
| -- This routine does not handle the case in which the interface is an |
| -- ancestor of Typ. That case is handled by the enclosing subprogram. |
| |
| pragma Assert (Typ /= Iface); |
| |
| -- Climb to the root type handling private types |
| |
| if Present (Full_View (Etype (Typ))) then |
| if Full_View (Etype (Typ)) /= Typ then |
| Find_Tag (Full_View (Etype (Typ))); |
| end if; |
| |
| elsif Etype (Typ) /= Typ then |
| Find_Tag (Etype (Typ)); |
| end if; |
| |
| -- Traverse the list of interfaces implemented by the type |
| |
| if not Found |
| and then Present (Interfaces (Typ)) |
| and then not (Is_Empty_Elmt_List (Interfaces (Typ))) |
| then |
| -- Skip the tag associated with the primary table |
| |
| pragma Assert (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag)); |
| AI_Tag := Next_Tag_Component (First_Tag_Component (Typ)); |
| pragma Assert (Present (AI_Tag)); |
| |
| AI_Elmt := First_Elmt (Interfaces (Typ)); |
| while Present (AI_Elmt) loop |
| AI := Node (AI_Elmt); |
| |
| if AI = Iface |
| or else Is_Ancestor (Iface, AI, Use_Full_View => True) |
| then |
| Found := True; |
| return; |
| end if; |
| |
| AI_Tag := Next_Tag_Component (AI_Tag); |
| Next_Elmt (AI_Elmt); |
| end loop; |
| end if; |
| end Find_Tag; |
| |
| -- Start of processing for Find_Interface_Tag |
| |
| begin |
| pragma Assert (Is_Interface (Iface)); |
| |
| -- Handle access types |
| |
| if Is_Access_Type (Typ) then |
| Typ := Designated_Type (Typ); |
| end if; |
| |
| -- Handle class-wide types |
| |
| if Is_Class_Wide_Type (Typ) then |
| Typ := Root_Type (Typ); |
| end if; |
| |
| -- Handle private types |
| |
| if Has_Private_Declaration (Typ) and then Present (Full_View (Typ)) then |
| Typ := Full_View (Typ); |
| end if; |
| |
| -- Handle entities from the limited view |
| |
| if Ekind (Typ) = E_Incomplete_Type then |
| pragma Assert (Present (Non_Limited_View (Typ))); |
| Typ := Non_Limited_View (Typ); |
| end if; |
| |
| -- Handle task and protected types implementing interfaces |
| |
| if Is_Concurrent_Type (Typ) then |
| Typ := Corresponding_Record_Type (Typ); |
| end if; |
| |
| -- If the interface is an ancestor of the type, then it shared the |
| -- primary dispatch table. |
| |
| if Is_Ancestor (Iface, Typ, Use_Full_View => True) then |
| pragma Assert (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag)); |
| return First_Tag_Component (Typ); |
| |
| -- Otherwise we need to search for its associated tag component |
| |
| else |
| Find_Tag (Typ); |
| pragma Assert (Found); |
| return AI_Tag; |
| end if; |
| end Find_Interface_Tag; |
| |
| ------------------ |
| -- Find_Prim_Op -- |
| ------------------ |
| |
| function Find_Prim_Op (T : Entity_Id; Name : Name_Id) return Entity_Id is |
| Prim : Elmt_Id; |
| Typ : Entity_Id := T; |
| Op : Entity_Id; |
| |
| begin |
| if Is_Class_Wide_Type (Typ) then |
| Typ := Root_Type (Typ); |
| end if; |
| |
| Typ := Underlying_Type (Typ); |
| |
| -- Loop through primitive operations |
| |
| Prim := First_Elmt (Primitive_Operations (Typ)); |
| while Present (Prim) loop |
| Op := Node (Prim); |
| |
| -- We can retrieve primitive operations by name if it is an internal |
| -- name. For equality we must check that both of its operands have |
| -- the same type, to avoid confusion with user-defined equalities |
| -- than may have a non-symmetric signature. |
| |
| exit when Chars (Op) = Name |
| and then |
| (Name /= Name_Op_Eq |
| or else Etype (First_Formal (Op)) = Etype (Last_Formal (Op))); |
| |
| Next_Elmt (Prim); |
| |
| -- Raise Program_Error if no primitive found |
| |
| if No (Prim) then |
| raise Program_Error; |
| end if; |
| end loop; |
| |
| return Node (Prim); |
| end Find_Prim_Op; |
| |
| ------------------ |
| -- Find_Prim_Op -- |
| ------------------ |
| |
| function Find_Prim_Op |
| (T : Entity_Id; |
| Name : TSS_Name_Type) return Entity_Id |
| is |
| Inher_Op : Entity_Id := Empty; |
| Own_Op : Entity_Id := Empty; |
| Prim_Elmt : Elmt_Id; |
| Prim_Id : Entity_Id; |
| Typ : Entity_Id := T; |
| |
| begin |
| if Is_Class_Wide_Type (Typ) then |
| Typ := Root_Type (Typ); |
| end if; |
| |
| Typ := Underlying_Type (Typ); |
| |
| -- This search is based on the assertion that the dispatching version |
| -- of the TSS routine always precedes the real primitive. |
| |
| Prim_Elmt := First_Elmt (Primitive_Operations (Typ)); |
| while Present (Prim_Elmt) loop |
| Prim_Id := Node (Prim_Elmt); |
| |
| if Is_TSS (Prim_Id, Name) then |
| if Present (Alias (Prim_Id)) then |
| Inher_Op := Prim_Id; |
| else |
| Own_Op := Prim_Id; |
| end if; |
| end if; |
| |
| Next_Elmt (Prim_Elmt); |
| end loop; |
| |
| if Present (Own_Op) then |
| return Own_Op; |
| elsif Present (Inher_Op) then |
| return Inher_Op; |
| else |
| raise Program_Error; |
| end if; |
| end Find_Prim_Op; |
| |
| ---------------------------- |
| -- Find_Protection_Object -- |
| ---------------------------- |
| |
| function Find_Protection_Object (Scop : Entity_Id) return Entity_Id is |
| S : Entity_Id; |
| |
| begin |
| S := Scop; |
| while Present (S) loop |
| if Ekind_In (S, E_Entry, E_Entry_Family, E_Function, E_Procedure) |
| and then Present (Protection_Object (S)) |
| then |
| return Protection_Object (S); |
| end if; |
| |
| S := Scope (S); |
| end loop; |
| |
| -- If we do not find a Protection object in the scope chain, then |
| -- something has gone wrong, most likely the object was never created. |
| |
| raise Program_Error; |
| end Find_Protection_Object; |
| |
| -------------------------- |
| -- Find_Protection_Type -- |
| -------------------------- |
| |
| function Find_Protection_Type (Conc_Typ : Entity_Id) return Entity_Id is |
| Comp : Entity_Id; |
| Typ : Entity_Id := Conc_Typ; |
| |
| begin |
| if Is_Concurrent_Type (Typ) then |
| Typ := Corresponding_Record_Type (Typ); |
| end if; |
| |
| -- Since restriction violations are not considered serious errors, the |
| -- expander remains active, but may leave the corresponding record type |
| -- malformed. In such cases, component _object is not available so do |
| -- not look for it. |
| |
| if not Analyzed (Typ) then |
| return Empty; |
| end if; |
| |
| Comp := First_Component (Typ); |
| while Present (Comp) loop |
| if Chars (Comp) = Name_uObject then |
| return Base_Type (Etype (Comp)); |
| end if; |
| |
| Next_Component (Comp); |
| end loop; |
| |
| -- The corresponding record of a protected type should always have an |
| -- _object field. |
| |
| raise Program_Error; |
| end Find_Protection_Type; |
| |
| ---------------------- |
| -- Force_Evaluation -- |
| ---------------------- |
| |
| procedure Force_Evaluation (Exp : Node_Id; Name_Req : Boolean := False) is |
| begin |
| Remove_Side_Effects (Exp, Name_Req, Variable_Ref => True); |
| end Force_Evaluation; |
| |
| --------------------------------- |
| -- Fully_Qualified_Name_String -- |
| --------------------------------- |
| |
| function Fully_Qualified_Name_String (E : Entity_Id) return String_Id is |
| procedure Internal_Full_Qualified_Name (E : Entity_Id); |
| -- Compute recursively the qualified name without NUL at the end, adding |
| -- it to the currently started string being generated |
| |
| ---------------------------------- |
| -- Internal_Full_Qualified_Name -- |
| ---------------------------------- |
| |
| procedure Internal_Full_Qualified_Name (E : Entity_Id) is |
| Ent : Entity_Id; |
| |
| begin |
| -- Deal properly with child units |
| |
| if Nkind (E) = N_Defining_Program_Unit_Name then |
| Ent := Defining_Identifier (E); |
| else |
| Ent := E; |
| end if; |
| |
| -- Compute qualification recursively (only "Standard" has no scope) |
| |
| if Present (Scope (Scope (Ent))) then |
| Internal_Full_Qualified_Name (Scope (Ent)); |
| Store_String_Char (Get_Char_Code ('.')); |
| end if; |
| |
| -- Every entity should have a name except some expanded blocks |
| -- don't bother about those. |
| |
| if Chars (Ent) = No_Name then |
| return; |
| end if; |
| |
| -- Generates the entity name in upper case |
| |
| Get_Decoded_Name_String (Chars (Ent)); |
| Set_All_Upper_Case; |
| Store_String_Chars (Name_Buffer (1 .. Name_Len)); |
| return; |
| end Internal_Full_Qualified_Name; |
| |
| -- Start of processing for Full_Qualified_Name |
| |
| begin |
| Start_String; |
| Internal_Full_Qualified_Name (E); |
| Store_String_Char (Get_Char_Code (ASCII.NUL)); |
| return End_String; |
| end Fully_Qualified_Name_String; |
| |
| ------------------------ |
| -- Generate_Poll_Call -- |
| ------------------------ |
| |
| procedure Generate_Poll_Call (N : Node_Id) is |
| begin |
| -- No poll call if polling not active |
| |
| if not Polling_Required then |
| return; |
| |
| -- Otherwise generate require poll call |
| |
| else |
| Insert_Before_And_Analyze (N, |
| Make_Procedure_Call_Statement (Sloc (N), |
| Name => New_Occurrence_Of (RTE (RE_Poll), Sloc (N)))); |
| end if; |
| end Generate_Poll_Call; |
| |
| --------------------------------- |
| -- Get_Current_Value_Condition -- |
| --------------------------------- |
| |
| -- Note: the implementation of this procedure is very closely tied to the |
| -- implementation of Set_Current_Value_Condition. In the Get procedure, we |
| -- interpret Current_Value fields set by the Set procedure, so the two |
| -- procedures need to be closely coordinated. |
| |
| procedure Get_Current_Value_Condition |
| (Var : Node_Id; |
| Op : out Node_Kind; |
| Val : out Node_Id) |
| is |
| Loc : constant Source_Ptr := Sloc (Var); |
| Ent : constant Entity_Id := Entity (Var); |
| |
| procedure Process_Current_Value_Condition |
| (N : Node_Id; |
| S : Boolean); |
| -- N is an expression which holds either True (S = True) or False (S = |
| -- False) in the condition. This procedure digs out the expression and |
| -- if it refers to Ent, sets Op and Val appropriately. |
| |
| ------------------------------------- |
| -- Process_Current_Value_Condition -- |
| ------------------------------------- |
| |
| procedure Process_Current_Value_Condition |
| (N : Node_Id; |
| S : Boolean) |
| is |
| Cond : Node_Id; |
| Sens : Boolean; |
| |
| begin |
| Cond := N; |
| Sens := S; |
| |
| -- Deal with NOT operators, inverting sense |
| |
| while Nkind (Cond) = N_Op_Not loop |
| Cond := Right_Opnd (Cond); |
| Sens := not Sens; |
| end loop; |
| |
| -- Deal with AND THEN and AND cases |
| |
| if Nkind_In (Cond, N_And_Then, N_Op_And) then |
| |
| -- Don't ever try to invert a condition that is of the form of an |
| -- AND or AND THEN (since we are not doing sufficiently general |
| -- processing to allow this). |
| |
| if Sens = False then |
| Op := N_Empty; |
| Val := Empty; |
| return; |
| end if; |
| |
| -- Recursively process AND and AND THEN branches |
| |
| Process_Current_Value_Condition (Left_Opnd (Cond), True); |
| |
| if Op /= N_Empty then |
| return; |
| end if; |
| |
| Process_Current_Value_Condition (Right_Opnd (Cond), True); |
| return; |
| |
| -- Case of relational operator |
| |
| elsif Nkind (Cond) in N_Op_Compare then |
| Op := Nkind (Cond); |
| |
| -- Invert sense of test if inverted test |
| |
| if Sens = False then |
| case Op is |
| when N_Op_Eq => Op := N_Op_Ne; |
| when N_Op_Ne => Op := N_Op_Eq; |
| when N_Op_Lt => Op := N_Op_Ge; |
| when N_Op_Gt => Op := N_Op_Le; |
| when N_Op_Le => Op := N_Op_Gt; |
| when N_Op_Ge => Op := N_Op_Lt; |
| when others => raise Program_Error; |
| end case; |
| end if; |
| |
| -- Case of entity op value |
| |
| if Is_Entity_Name (Left_Opnd (Cond)) |
| and then Ent = Entity (Left_Opnd (Cond)) |
| and then Compile_Time_Known_Value (Right_Opnd (Cond)) |
| then |
| Val := Right_Opnd (Cond); |
| |
| -- Case of value op entity |
| |
| elsif Is_Entity_Name (Right_Opnd (Cond)) |
| and then Ent = Entity (Right_Opnd (Cond)) |
| and then Compile_Time_Known_Value (Left_Opnd (Cond)) |
| then |
| Val := Left_Opnd (Cond); |
| |
| -- We are effectively swapping operands |
| |
| case Op is |
| when N_Op_Eq => null; |
| when N_Op_Ne => null; |
| when N_Op_Lt => Op := N_Op_Gt; |
| when N_Op_Gt => Op := N_Op_Lt; |
| when N_Op_Le => Op := N_Op_Ge; |
| when N_Op_Ge => Op := N_Op_Le; |
| when others => raise Program_Error; |
| end case; |
| |
| else |
| Op := N_Empty; |
| end if; |
| |
| return; |
| |
| -- Case of Boolean variable reference, return as though the |
| -- reference had said var = True. |
| |
| else |
| if Is_Entity_Name (Cond) and then Ent = Entity (Cond) then |
| Val := New_Occurrence_Of (Standard_True, Sloc (Cond)); |
| |
| if Sens = False then |
| Op := N_Op_Ne; |
| else |
| Op := N_Op_Eq; |
| end if; |
| end if; |
| end if; |
| end Process_Current_Value_Condition; |
| |
| -- Start of processing for Get_Current_Value_Condition |
| |
| begin |
| Op := N_Empty; |
| Val := Empty; |
| |
| -- Immediate return, nothing doing, if this is not an object |
| |
| if Ekind (Ent) not in Object_Kind then |
| return; |
| end if; |
| |
| -- Otherwise examine current value |
| |
| declare |
| CV : constant Node_Id := Current_Value (Ent); |
| Sens : Boolean; |
| Stm : Node_Id; |
| |
| begin |
| -- If statement. Condition is known true in THEN section, known False |
| -- in any ELSIF or ELSE part, and unknown outside the IF statement. |
| |
| if Nkind (CV) = N_If_Statement then |
| |
| -- Before start of IF statement |
| |
| if Loc < Sloc (CV) then |
| return; |
| |
| -- After end of IF statement |
| |
| elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then |
| return; |
| end if; |
| |
| -- At this stage we know that we are within the IF statement, but |
| -- unfortunately, the tree does not record the SLOC of the ELSE so |
| -- we cannot use a simple SLOC comparison to distinguish between |
| -- the then/else statements, so we have to climb the tree. |
| |
| declare |
| N : Node_Id; |
| |
| begin |
| N := Parent (Var); |
| while Parent (N) /= CV loop |
| N := Parent (N); |
| |
| -- If we fall off the top of the tree, then that's odd, but |
| -- perhaps it could occur in some error situation, and the |
| -- safest response is simply to assume that the outcome of |
| -- the condition is unknown. No point in bombing during an |
| -- attempt to optimize things. |
| |
| if No (N) then |
| return; |
| end if; |
| end loop; |
| |
| -- Now we have N pointing to a node whose parent is the IF |
| -- statement in question, so now we can tell if we are within |
| -- the THEN statements. |
| |
| if Is_List_Member (N) |
| and then List_Containing (N) = Then_Statements (CV) |
| then |
| Sens := True; |
| |
| -- If the variable reference does not come from source, we |
| -- cannot reliably tell whether it appears in the else part. |
| -- In particular, if it appears in generated code for a node |
| -- that requires finalization, it may be attached to a list |
| -- that has not been yet inserted into the code. For now, |
| -- treat it as unknown. |
| |
| elsif not Comes_From_Source (N) then |
| return; |
| |
| -- Otherwise we must be in ELSIF or ELSE part |
| |
| else |
| Sens := False; |
| end if; |
| end; |
| |
| -- ELSIF part. Condition is known true within the referenced |
| -- ELSIF, known False in any subsequent ELSIF or ELSE part, |
| -- and unknown before the ELSE part or after the IF statement. |
| |
| elsif Nkind (CV) = N_Elsif_Part then |
| |
| -- if the Elsif_Part had condition_actions, the elsif has been |
| -- rewritten as a nested if, and the original elsif_part is |
| -- detached from the tree, so there is no way to obtain useful |
| -- information on the current value of the variable. |
| -- Can this be improved ??? |
| |
| if No (Parent (CV)) then |
| return; |
| end if; |
| |
| Stm := Parent (CV); |
| |
| -- Before start of ELSIF part |
| |
| if Loc < Sloc (CV) then |
| return; |
| |
| -- After end of IF statement |
| |
| elsif Loc >= Sloc (Stm) + |
| Text_Ptr (UI_To_Int (End_Span (Stm))) |
| then |
| return; |
| end if; |
| |
| -- Again we lack the SLOC of the ELSE, so we need to climb the |
| -- tree to see if we are within the ELSIF part in question. |
| |
| declare |
| N : Node_Id; |
| |
| begin |
| N := Parent (Var); |
| while Parent (N) /= Stm loop |
| N := Parent (N); |
| |
| -- If we fall off the top of the tree, then that's odd, but |
| -- perhaps it could occur in some error situation, and the |
| -- safest response is simply to assume that the outcome of |
| -- the condition is unknown. No point in bombing during an |
| -- attempt to optimize things. |
| |
| if No (N) then |
| return; |
| end if; |
| end loop; |
| |
| -- Now we have N pointing to a node whose parent is the IF |
| -- statement in question, so see if is the ELSIF part we want. |
| -- the THEN statements. |
| |
| if N = CV then |
| Sens := True; |
| |
| -- Otherwise we must be in subsequent ELSIF or ELSE part |
| |
| else |
| Sens := False; |
| end if; |
| end; |
| |
| -- Iteration scheme of while loop. The condition is known to be |
| -- true within the body of the loop. |
| |
| elsif Nkind (CV) = N_Iteration_Scheme then |
| declare |
| Loop_Stmt : constant Node_Id := Parent (CV); |
| |
| begin |
| -- Before start of body of loop |
| |
| if Loc < Sloc (Loop_Stmt) then |
| return; |
| |
| -- After end of LOOP statement |
| |
| elsif Loc >= Sloc (End_Label (Loop_Stmt)) then |
| return; |
| |
| -- We are within the body of the loop |
| |
| else |
| Sens := True; |
| end if; |
| end; |
| |
| -- All other cases of Current_Value settings |
| |
| else |
| return; |
| end if; |
| |
| -- If we fall through here, then we have a reportable condition, Sens |
| -- is True if the condition is true and False if it needs inverting. |
| |
| Process_Current_Value_Condition (Condition (CV), Sens); |
| end; |
| end Get_Current_Value_Condition; |
| |
| --------------------- |
| -- Get_Stream_Size -- |
| --------------------- |
| |
| function Get_Stream_Size (E : Entity_Id) return Uint is |
| begin |
| -- If we have a Stream_Size clause for this type use it |
| |
| if Has_Stream_Size_Clause (E) then |
| return Static_Integer (Expression (Stream_Size_Clause (E))); |
| |
| -- Otherwise the Stream_Size if the size of the type |
| |
| else |
| return Esize (E); |
| end if; |
| end Get_Stream_Size; |
| |
| --------------------------- |
| -- Has_Access_Constraint -- |
| --------------------------- |
| |
| function Has_Access_Constraint (E : Entity_Id) return Boolean is |
| Disc : Entity_Id; |
| T : constant Entity_Id := Etype (E); |
| |
| begin |
| if Has_Per_Object_Constraint (E) and then Has_Discriminants (T) then |
| Disc := First_Discriminant (T); |
| while Present (Disc) loop |
| if Is_Access_Type (Etype (Disc)) then |
| return True; |
| end if; |
| |
| Next_Discriminant (Disc); |
| end loop; |
| |
| return False; |
| else |
| return False; |
| end if; |
| end Has_Access_Constraint; |
| |
| ---------------------------------- |
| -- Has_Following_Address_Clause -- |
| ---------------------------------- |
| |
| -- Should this function check the private part in a package ??? |
| |
| function Has_Following_Address_Clause (D : Node_Id) return Boolean is |
| Id : constant Entity_Id := Defining_Identifier (D); |
| Decl : Node_Id; |
| |
| begin |
| Decl := Next (D); |
| while Present (Decl) loop |
| if Nkind (Decl) = N_At_Clause |
| and then Chars (Identifier (Decl)) = Chars (Id) |
| then |
| return True; |
| |
| elsif Nkind (Decl) = N_Attribute_Definition_Clause |
| and then Chars (Decl) = Name_Address |
| and then Chars (Name (Decl)) = Chars (Id) |
| then |
| return True; |
| end if; |
| |
| Next (Decl); |
| end loop; |
| |
| return False; |
| end Has_Following_Address_Clause; |
| |
| -------------------- |
| -- Homonym_Number -- |
| -------------------- |
| |
| function Homonym_Number (Subp : Entity_Id) return Nat is |
| Count : Nat; |
| Hom : Entity_Id; |
| |
| begin |
| Count := 1; |
| Hom := Homonym (Subp); |
| while Present (Hom) loop |
| if Scope (Hom) = Scope (Subp) then |
| Count := Count + 1; |
| end if; |
| |
| Hom := Homonym (Hom); |
| end loop; |
| |
| return Count; |
| end Homonym_Number; |
| |
| ----------------------------------- |
| -- In_Library_Level_Package_Body -- |
| ----------------------------------- |
| |
| function In_Library_Level_Package_Body (Id : Entity_Id) return Boolean is |
| begin |
| -- First determine whether the entity appears at the library level, then |
| -- look at the containing unit. |
| |
| if Is_Library_Level_Entity (Id) then |
| declare |
| Container : constant Node_Id := Cunit (Get_Source_Unit (Id)); |
| |
| begin |
| return Nkind (Unit (Container)) = N_Package_Body; |
| end; |
| end if; |
| |
| return False; |
| end In_Library_Level_Package_Body; |
| |
| ------------------------------ |
| -- In_Unconditional_Context -- |
| ------------------------------ |
| |
| function In_Unconditional_Context (Node : Node_Id) return Boolean is |
| P : Node_Id; |
| |
| begin |
| P := Node; |
| while Present (P) loop |
| case Nkind (P) is |
| when N_Subprogram_Body => |
| return True; |
| |
| when N_If_Statement => |
| return False; |
| |
| when N_Loop_Statement => |
| return False; |
| |
| when N_Case_Statement => |
| return False; |
| |
| when others => |
| P := Parent (P); |
| end case; |
| end loop; |
| |
| return False; |
| end In_Unconditional_Context; |
| |
| ------------------- |
| -- Insert_Action -- |
| ------------------- |
| |
| procedure Insert_Action (Assoc_Node : Node_Id; Ins_Action : Node_Id) is |
| begin |
| if Present (Ins_Action) then |
| Insert_Actions (Assoc_Node, New_List (Ins_Action)); |
| end if; |
| end Insert_Action; |
| |
| -- Version with check(s) suppressed |
| |
| procedure Insert_Action |
| (Assoc_Node : Node_Id; Ins_Action : Node_Id; Suppress : Check_Id) |
| is |
| begin |
| Insert_Actions (Assoc_Node, New_List (Ins_Action), Suppress); |
| end Insert_Action; |
| |
| ------------------------- |
| -- Insert_Action_After -- |
| ------------------------- |
| |
| procedure Insert_Action_After |
| (Assoc_Node : Node_Id; |
| Ins_Action : Node_Id) |
| is |
| begin |
| Insert_Actions_After (Assoc_Node, New_List (Ins_Action)); |
| end Insert_Action_After; |
| |
| -------------------- |
| -- Insert_Actions -- |
| -------------------- |
| |
| procedure Insert_Actions (Assoc_Node : Node_Id; Ins_Actions : List_Id) is |
| N : Node_Id; |
| P : Node_Id; |
| |
| Wrapped_Node : Node_Id := Empty; |
| |
| begin |
| if No (Ins_Actions) or else Is_Empty_List (Ins_Actions) then |
| return; |
| end if; |
| |
| -- Ignore insert of actions from inside default expression (or other |
| -- similar "spec expression") in the special spec-expression analyze |
| -- mode. Any insertions at this point have no relevance, since we are |
| -- only doing the analyze to freeze the types of any static expressions. |
| -- See section "Handling of Default Expressions" in the spec of package |
| -- Sem for further details. |
| |
| if In_Spec_Expression then |
| return; |
| end if; |
| |
| -- If the action derives from stuff inside a record, then the actions |
| -- are attached to the current scope, to be inserted and analyzed on |
| -- exit from the scope. The reason for this is that we may also be |
| -- generating freeze actions at the same time, and they must eventually |
| -- be elaborated in the correct order. |
| |
| if Is_Record_Type (Current_Scope) |
| and then not Is_Frozen (Current_Scope) |
| then |
| if No (Scope_Stack.Table |
| (Scope_Stack.Last).Pending_Freeze_Actions) |
| then |
| Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions := |
| Ins_Actions; |
| else |
| Append_List |
| (Ins_Actions, |
| Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions); |
| end if; |
| |
| return; |
| end if; |
| |
| -- We now intend to climb up the tree to find the right point to |
| -- insert the actions. We start at Assoc_Node, unless this node is a |
| -- subexpression in which case we start with its parent. We do this for |
| -- two reasons. First it speeds things up. Second, if Assoc_Node is |
| -- itself one of the special nodes like N_And_Then, then we assume that |
| -- an initial request to insert actions for such a node does not expect |
| -- the actions to get deposited in the node for later handling when the |
| -- node is expanded, since clearly the node is being dealt with by the |
| -- caller. Note that in the subexpression case, N is always the child we |
| -- came from. |
| |
| -- N_Raise_xxx_Error is an annoying special case, it is a statement if |
| -- it has type Standard_Void_Type, and a subexpression otherwise. |
| -- otherwise. Procedure calls, and similarly procedure attribute |
| -- references, are also statements. |
| |
| if Nkind (Assoc_Node) in N_Subexpr |
| and then (Nkind (Assoc_Node) not in N_Raise_xxx_Error |
| or else Etype (Assoc_Node) /= Standard_Void_Type) |
| and then Nkind (Assoc_Node) /= N_Procedure_Call_Statement |
| and then (Nkind (Assoc_Node) /= N_Attribute_Reference |
| or else |
| not Is_Procedure_Attribute_Name |
| (Attribute_Name (Assoc_Node))) |
| then |
| N := Assoc_Node; |
| P := Parent (Assoc_Node); |
| |
| -- Non-subexpression case. Note that N is initially Empty in this case |
| -- (N is only guaranteed Non-Empty in the subexpr case). |
| |
| else |
| N := Empty; |
| P := Assoc_Node; |
| end if; |
| |
| -- Capture root of the transient scope |
| |
| if Scope_Is_Transient then |
| Wrapped_Node := Node_To_Be_Wrapped; |
| end if; |
| |
| loop |
| pragma Assert (Present (P)); |
| |
| -- Make sure that inserted actions stay in the transient scope |
| |
| if Present (Wrapped_Node) and then N = Wrapped_Node then |
| Store_Before_Actions_In_Scope (Ins_Actions); |
| return; |
| end if; |
| |
| case Nkind (P) is |
| |
| -- Case of right operand of AND THEN or OR ELSE. Put the actions |
| -- in the Actions field of the right operand. They will be moved |
| -- out further when the AND THEN or OR ELSE operator is expanded. |
| -- Nothing special needs to be done for the left operand since |
| -- in that case the actions are executed unconditionally. |
| |
| when N_Short_Circuit => |
| if N = Right_Opnd (P) then |
| |
| -- We are now going to either append the actions to the |
| -- actions field of the short-circuit operation. We will |
| -- also analyze the actions now. |
| |
| -- This analysis is really too early, the proper thing would |
| -- be to just park them there now, and only analyze them if |
| -- we find we really need them, and to it at the proper |
| -- final insertion point. However attempting to this proved |
| -- tricky, so for now we just kill current values before and |
| -- after the analyze call to make sure we avoid peculiar |
| -- optimizations from this out of order insertion. |
| |
| Kill_Current_Values; |
| |
| if Present (Actions (P)) then |
| Insert_List_After_And_Analyze |
| (Last (Actions (P)), Ins_Actions); |
| else |
| Set_Actions (P, Ins_Actions); |
| Analyze_List (Actions (P)); |
| end if; |
| |
| Kill_Current_Values; |
| |
| return; |
| end if; |
| |
| -- Then or Else dependent expression of an if expression. Add |
| -- actions to Then_Actions or Else_Actions field as appropriate. |
| -- The actions will be moved further out when the if is expanded. |
| |
| when N_If_Expression => |
| declare |
| ThenX : constant Node_Id := Next (First (Expressions (P))); |
| ElseX : constant Node_Id := Next (ThenX); |
| |
| begin |
| -- If the enclosing expression is already analyzed, as |
| -- is the case for nested elaboration checks, insert the |
| -- conditional further out. |
| |
| if Analyzed (P) then |
| null; |
| |
| -- Actions belong to the then expression, temporarily place |
| -- them as Then_Actions of the if expression. They will be |
| -- moved to the proper place later when the if expression |
| -- is expanded. |
| |
| elsif N = ThenX then |
| if Present (Then_Actions (P)) then |
| Insert_List_After_And_Analyze |
| (Last (Then_Actions (P)), Ins_Actions); |
| else |
| Set_Then_Actions (P, Ins_Actions); |
| Analyze_List (Then_Actions (P)); |
| end if; |
| |
| return; |
| |
| -- Actions belong to the else expression, temporarily place |
| -- them as Else_Actions of the if expression. They will be |
| -- moved to the proper place later when the if expression |
| -- is expanded. |
| |
| elsif N = ElseX then |
| if Present (Else_Actions (P)) then |
| Insert_List_After_And_Analyze |
| (Last (Else_Actions (P)), Ins_Actions); |
| else |
| Set_Else_Actions (P, Ins_Actions); |
| Analyze_List (Else_Actions (P)); |
| end if; |
| |
| return; |
| |
| -- Actions belong to the condition. In this case they are |
| -- unconditionally executed, and so we can continue the |
| -- search for the proper insert point. |
| |
| else |
| null; |
| end if; |
| end; |
| |
| -- Alternative of case expression, we place the action in the |
| -- Actions field of the case expression alternative, this will |
| -- be handled when the case expression is expanded. |
| |
| when N_Case_Expression_Alternative => |
| if Present (Actions (P)) then |
| Insert_List_After_And_Analyze |
| (Last (Actions (P)), Ins_Actions); |
| else |
| Set_Actions (P, Ins_Actions); |
| Analyze_List (Actions (P)); |
| end if; |
| |
| return; |
| |
| -- Case of appearing within an Expressions_With_Actions node. When |
| -- the new actions come from the expression of the expression with |
| -- actions, they must be added to the existing actions. The other |
| -- alternative is when the new actions are related to one of the |
| -- existing actions of the expression with actions. In that case |
| -- they must be inserted further up the tree. |
| |
| when N_Expression_With_Actions => |
| if N = Expression (P) then |
| Insert_List_After_And_Analyze |
| (Last (Actions (P)), Ins_Actions); |
| return; |
| end if; |
| |
| -- Case of appearing in the condition of a while expression or |
| -- elsif. We insert the actions into the Condition_Actions field. |
| -- They will be moved further out when the while loop or elsif |
| -- is analyzed. |
| |
| when N_Iteration_Scheme | |
| N_Elsif_Part |
| => |
| if N = Condition (P) then |
| if Present (Condition_Actions (P)) then |
| Insert_List_After_And_Analyze |
| (Last (Condition_Actions (P)), Ins_Actions); |
| else |
| Set_Condition_Actions (P, Ins_Actions); |
| |
| -- Set the parent of the insert actions explicitly. This |
| -- is not a syntactic field, but we need the parent field |
| -- set, in particular so that freeze can understand that |
| -- it is dealing with condition actions, and properly |
| -- insert the freezing actions. |
| |
| Set_Parent (Ins_Actions, P); |
| Analyze_List (Condition_Actions (P)); |
| end if; |
| |
| return; |
| end if; |
| |
| -- Statements, declarations, pragmas, representation clauses |
| |
| when |
| -- Statements |
| |
| N_Procedure_Call_Statement | |
| N_Statement_Other_Than_Procedure_Call | |
| |
| -- Pragmas |
| |
| N_Pragma | |
| |
| -- Representation_Clause |
| |
| N_At_Clause | |
| N_Attribute_Definition_Clause | |
| N_Enumeration_Representation_Clause | |
| N_Record_Representation_Clause | |
| |
| -- Declarations |
| |
| N_Abstract_Subprogram_Declaration | |
| N_Entry_Body | |
| N_Exception_Declaration | |
| N_Exception_Renaming_Declaration | |
| N_Expression_Function | |
| N_Formal_Abstract_Subprogram_Declaration | |
| N_Formal_Concrete_Subprogram_Declaration | |
| N_Formal_Object_Declaration | |
| N_Formal_Type_Declaration | |
| N_Full_Type_Declaration | |
| N_Function_Instantiation | |
| N_Generic_Function_Renaming_Declaration | |
| N_Generic_Package_Declaration | |
| N_Generic_Package_Renaming_Declaration | |
| N_Generic_Procedure_Renaming_Declaration | |
| N_Generic_Subprogram_Declaration | |
| N_Implicit_Label_Declaration | |
| N_Incomplete_Type_Declaration | |
| N_Number_Declaration | |
| N_Object_Declaration | |
| N_Object_Renaming_Declaration | |
| N_Package_Body | |
| N_Package_Body_Stub | |
| N_Package_Declaration | |
| N_Package_Instantiation | |
| N_Package_Renaming_Declaration | |
| N_Private_Extension_Declaration | |
| N_Private_Type_Declaration | |
| N_Procedure_Instantiation | |
| N_Protected_Body | |
| N_Protected_Body_Stub | |
| N_Protected_Type_Declaration | |
| N_Single_Task_Declaration | |
| N_Subprogram_Body | |
| N_Subprogram_Body_Stub | |
| N_Subprogram_Declaration | |
| N_Subprogram_Renaming_Declaration | |
| N_Subtype_Declaration | |
| N_Task_Body | |
| N_Task_Body_Stub | |
| N_Task_Type_Declaration | |
| |
| -- Use clauses can appear in lists of declarations |
| |
| N_Use_Package_Clause | |
| N_Use_Type_Clause | |
| |
| -- Freeze entity behaves like a declaration or statement |
| |
| N_Freeze_Entity |
| => |
| -- Do not insert here if the item is not a list member (this |
| -- happens for example with a triggering statement, and the |
| -- proper approach is to insert before the entire select). |
| |
| if not Is_List_Member (P) then |
| null; |
| |
| -- Do not insert if parent of P is an N_Component_Association |
| -- node (i.e. we are in the context of an N_Aggregate or |
| -- N_Extension_Aggregate node. In this case we want to insert |
| -- before the entire aggregate. |
| |
| elsif Nkind (Parent (P)) = N_Component_Association then |
| null; |
| |
| -- Do not insert if the parent of P is either an N_Variant node |
| -- or an N_Record_Definition node, meaning in either case that |
| -- P is a member of a component list, and that therefore the |
| -- actions should be inserted outside the complete record |
| -- declaration. |
| |
| elsif Nkind_In (Parent (P), N_Variant, N_Record_Definition) then |
| null; |
| |
| -- Do not insert freeze nodes within the loop generated for |
| -- an aggregate, because they may be elaborated too late for |
| -- subsequent use in the back end: within a package spec the |
| -- loop is part of the elaboration procedure and is only |
| -- elaborated during the second pass. |
| |
| -- If the loop comes from source, or the entity is local to the |
| -- loop itself it must remain within. |
| |
| elsif Nkind (Parent (P)) = N_Loop_Statement |
| and then not Comes_From_Source (Parent (P)) |
| and then Nkind (First (Ins_Actions)) = N_Freeze_Entity |
| and then |
| Scope (Entity (First (Ins_Actions))) /= Current_Scope |
| then |
| null; |
| |
| -- Otherwise we can go ahead and do the insertion |
| |
| elsif P = Wrapped_Node then |
| Store_Before_Actions_In_Scope (Ins_Actions); |
| return; |
| |
| else |
| Insert_List_Before_And_Analyze (P, Ins_Actions); |
| return; |
| end if; |
| |
| -- A special case, N_Raise_xxx_Error can act either as a statement |
| -- or a subexpression. We tell the difference by looking at the |
| -- Etype. It is set to Standard_Void_Type in the statement case. |
| |
| when |
| N_Raise_xxx_Error => |
| if Etype (P) = Standard_Void_Type then |
| if P = Wrapped_Node then |
| Store_Before_Actions_In_Scope (Ins_Actions); |
| else |
| Insert_List_Before_And_Analyze (P, Ins_Actions); |
| end if; |
| |
| return; |
| |
| -- In the subexpression case, keep climbing |
| |
| else |
| null; |
| end if; |
| |
| -- If a component association appears within a loop created for |
| -- an array aggregate, attach the actions to the association so |
| -- they can be subsequently inserted within the loop. For other |
| -- component associations insert outside of the aggregate. For |
| -- an association that will generate a loop, its Loop_Actions |
| -- attribute is already initialized (see exp_aggr.adb). |
| |
| -- The list of loop_actions can in turn generate additional ones, |
| -- that are inserted before the associated node. If the associated |
| -- node is outside the aggregate, the new actions are collected |
| -- at the end of the loop actions, to respect the order in which |
| -- they are to be elaborated. |
| |
| when |
| N_Component_Association => |
| if Nkind (Parent (P)) = N_Aggregate |
| and then Present (Loop_Actions (P)) |
| then |
| if Is_Empty_List (Loop_Actions (P)) then |
| Set_Loop_Actions (P, Ins_Actions); |
| Analyze_List (Ins_Actions); |
| |
| else |
| declare |
| Decl : Node_Id; |
| |
| begin |
| -- Check whether these actions were generated by a |
| -- declaration that is part of the loop_ actions |
| -- for the component_association. |
| |
| Decl := Assoc_Node; |
| while Present (Decl) loop |
| exit when Parent (Decl) = P |
| and then Is_List_Member (Decl) |
| and then |
| List_Containing (Decl) = Loop_Actions (P); |
| Decl := Parent (Decl); |
| end loop; |
| |
| if Present (Decl) then |
| Insert_List_Before_And_Analyze |
| (Decl, Ins_Actions); |
| else |
| Insert_List_After_And_Analyze |
| (Last (Loop_Actions (P)), Ins_Actions); |
| end if; |
| end; |
| end if; |
| |
| return; |
| |
| else |
| null; |
| end if; |
| |
| -- Another special case, an attribute denoting a procedure call |
| |
| when |
| N_Attribute_Reference => |
| if Is_Procedure_Attribute_Name (Attribute_Name (P)) then |
| if P = Wrapped_Node then |
| Store_Before_Actions_In_Scope (Ins_Actions); |
| else |
| Insert_List_Before_And_Analyze (P, Ins_Actions); |
| end if; |
| |
| return; |
| |
| -- In the subexpression case, keep climbing |
| |
| else |
| null; |
| end if; |
| |
| -- A contract node should not belong to the tree |
| |
| when N_Contract => |
| raise Program_Error; |
| |
| -- For all other node types, keep climbing tree |
| |
| when |
| N_Abortable_Part | |
| N_Accept_Alternative | |
| N_Access_Definition | |
| N_Access_Function_Definition | |
| N_Access_Procedure_Definition | |
| N_Access_To_Object_Definition | |
| N_Aggregate | |
| N_Allocator | |
| N_Aspect_Specification | |
| N_Case_Expression | |
| N_Case_Statement_Alternative | |
| N_Character_Literal | |
| N_Compilation_Unit | |
| N_Compilation_Unit_Aux | |
| N_Component_Clause | |
| N_Component_Declaration | |
| N_Component_Definition | |
| N_Component_List | |
| N_Constrained_Array_Definition | |
| N_Decimal_Fixed_Point_Definition | |
| N_Defining_Character_Literal | |
| N_Defining_Identifier | |
| N_Defining_Operator_Symbol | |
| N_Defining_Program_Unit_Name | |
| N_Delay_Alternative | |
| N_Delta_Constraint | |
| N_Derived_Type_Definition | |
| N_Designator | |
| N_Digits_Constraint | |
| N_Discriminant_Association | |
| N_Discriminant_Specification | |
| N_Empty | |
| N_Entry_Body_Formal_Part | |
| N_Entry_Call_Alternative | |
| N_Entry_Declaration | |
| N_Entry_Index_Specification | |
| N_Enumeration_Type_Definition | |
| N_Error | |
| N_Exception_Handler | |
| N_Expanded_Name | |
| N_Explicit_Dereference | |
| N_Extension_Aggregate | |
| N_Floating_Point_Definition | |
| N_Formal_Decimal_Fixed_Point_Definition | |
| N_Formal_Derived_Type_Definition | |
| N_Formal_Discrete_Type_Definition | |
| N_Formal_Floating_Point_Definition | |
| N_Formal_Modular_Type_Definition | |
| N_Formal_Ordinary_Fixed_Point_Definition | |
| N_Formal_Package_Declaration | |
| N_Formal_Private_Type_Definition | |
| N_Formal_Incomplete_Type_Definition | |
| N_Formal_Signed_Integer_Type_Definition | |
| N_Function_Call | |
| N_Function_Specification | |
| N_Generic_Association | |
| N_Handled_Sequence_Of_Statements | |
| N_Identifier | |
| N_In | |
| N_Index_Or_Discriminant_Constraint | |
| N_Indexed_Component | |
| N_Integer_Literal | |
| N_Iterator_Specification | |
| N_Itype_Reference | |
| N_Label | |
| N_Loop_Parameter_Specification | |
| N_Mod_Clause | |
| N_Modular_Type_Definition | |
| N_Not_In | |
| N_Null | |
| N_Op_Abs | |
| N_Op_Add | |
| N_Op_And | |
| N_Op_Concat | |
| N_Op_Divide | |
| N_Op_Eq | |
| N_Op_Expon | |
| N_Op_Ge | |
| N_Op_Gt | |
| N_Op_Le | |
| N_Op_Lt | |
| N_Op_Minus | |
| N_Op_Mod | |
| N_Op_Multiply | |
| N_Op_Ne | |
| N_Op_Not | |
| N_Op_Or | |
| N_Op_Plus | |
| N_Op_Rem | |
| N_Op_Rotate_Left | |
| N_Op_Rotate_Right | |
| N_Op_Shift_Left | |
| N_Op_Shift_Right | |
| N_Op_Shift_Right_Arithmetic | |
| N_Op_Subtract | |
| N_Op_Xor | |
| N_Operator_Symbol | |
| N_Ordinary_Fixed_Point_Definition | |
| N_Others_Choice | |
| N_Package_Specification | |
| N_Parameter_Association | |
| N_Parameter_Specification | |
| N_Pop_Constraint_Error_Label | |
| N_Pop_Program_Error_Label | |
| N_Pop_Storage_Error_Label | |
| N_Pragma_Argument_Association | |
| N_Procedure_Specification | |
| N_Protected_Definition | |
| N_Push_Constraint_Error_Label | |
| N_Push_Program_Error_Label | |
| N_Push_Storage_Error_Label | |
| N_Qualified_Expression | |
| N_Quantified_Expression | |
| N_Range | |
| N_Range_Constraint | |
| N_Real_Literal | |
| N_Real_Range_Specification | |
| N_Record_Definition | |
| N_Reference | |
| N_SCIL_Dispatch_Table_Tag_Init | |
| N_SCIL_Dispatching_Call | |
| N_SCIL_Membership_Test | |
| N_Selected_Component | |
| N_Signed_Integer_Type_Definition | |
| N_Single_Protected_Declaration | |
| N_Slice | |
| N_String_Literal | |
| N_Subprogram_Info | |
| N_Subtype_Indication | |
| N_Subunit | |
| N_Task_Definition | |
| N_Terminate_Alternative | |
| N_Triggering_Alternative | |
| N_Type_Conversion | |
| N_Unchecked_Expression | |
| N_Unchecked_Type_Conversion | |
| N_Unconstrained_Array_Definition | |
| N_Unused_At_End | |
| N_Unused_At_Start | |
| N_Variant | |
| N_Variant_Part | |
| N_Validate_Unchecked_Conversion | |
| N_With_Clause |
| => |
| null; |
| |
| end case; |
| |
| -- If we fall through above tests, keep climbing tree |
| |
| N := P; |
| |
| if Nkind (Parent (N)) = N_Subunit then |
| |
| -- This is the proper body corresponding to a stub. Insertion must |
| -- be done at the point of the stub, which is in the declarative |
| -- part of the parent unit. |
| |
| P := Corresponding_Stub (Parent (N)); |
| |
| else |
| P := Parent (N); |
| end if; |
| end loop; |
| end Insert_Actions; |
| |
| -- Version with check(s) suppressed |
| |
| procedure Insert_Actions |
| (Assoc_Node : Node_Id; |
| Ins_Actions : List_Id; |
| Suppress : Check_Id) |
| is |
| begin |
| if Suppress = All_Checks then |
| declare |
| Sva : constant Suppress_Array := Scope_Suppress.Suppress; |
| begin |
| Scope_Suppress.Suppress := (others => True); |
| Insert_Actions (Assoc_Node, Ins_Actions); |
| Scope_Suppress.Suppress := Sva; |
| end; |
| |
| else |
| declare |
| Svg : constant Boolean := Scope_Suppress.Suppress (Suppress); |
| begin |
| Scope_Suppress.Suppress (Suppress) := True; |
| Insert_Actions (Assoc_Node, Ins_Actions); |
| Scope_Suppress.Suppress (Suppress) := Svg; |
| end; |
| end if; |
| end Insert_Actions; |
| |
| -------------------------- |
| -- Insert_Actions_After -- |
| -------------------------- |
| |
| procedure Insert_Actions_After |
| (Assoc_Node : Node_Id; |
| Ins_Actions : List_Id) |
| is |
| begin |
| if Scope_Is_Transient and then Assoc_Node = Node_To_Be_Wrapped then |
| Store_After_Actions_In_Scope (Ins_Actions); |
| else |
| Insert_List_After_And_Analyze (Assoc_Node, Ins_Actions); |
| end if; |
| end Insert_Actions_After; |
| |
| --------------------------------- |
| -- Insert_Library_Level_Action -- |
| --------------------------------- |
| |
| procedure Insert_Library_Level_Action (N : Node_Id) is |
| Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit)); |
| |
| begin |
| Push_Scope (Cunit_Entity (Main_Unit)); |
| -- ??? should this be Current_Sem_Unit instead of Main_Unit? |
| |
| if No (Actions (Aux)) then |
| Set_Actions (Aux, New_List (N)); |
| else |
| Append (N, Actions (Aux)); |
| end if; |
| |
| Analyze (N); |
| Pop_Scope; |
| end Insert_Library_Level_Action; |
| |
| ---------------------------------- |
| -- Insert_Library_Level_Actions -- |
| ---------------------------------- |
| |
| procedure Insert_Library_Level_Actions (L : List_Id) is |
| Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit)); |
| |
| begin |
| if Is_Non_Empty_List (L) then |
| Push_Scope (Cunit_Entity (Main_Unit)); |
| -- ??? should this be Current_Sem_Unit instead of Main_Unit? |
| |
| if No (Actions (Aux)) then |
| Set_Actions (Aux, L); |
| Analyze_List (L); |
| else |
| Insert_List_After_And_Analyze (Last (Actions (Aux)), L); |
| end if; |
| |
| Pop_Scope; |
| end if; |
| end Insert_Library_Level_Actions; |
| |
| ---------------------- |
| -- Inside_Init_Proc -- |
| ---------------------- |
| |
| function Inside_Init_Proc return Boolean is |
| S : Entity_Id; |
| |
| begin |
| S := Current_Scope; |
| while Present (S) and then S /= Standard_Standard loop |
| if Is_Init_Proc (S) then |
| return True; |
| else |
| S := Scope (S); |
| end if; |
| end loop; |
| |
| return False; |
| end Inside_Init_Proc; |
| |
| ---------------------------- |
| -- Is_All_Null_Statements -- |
| ---------------------------- |
| |
| function Is_All_Null_Statements (L : List_Id) return Boolean is |
| Stm : Node_Id; |
| |
| begin |
| Stm := First (L); |
| while Present (Stm) loop |
| if Nkind (Stm) /= N_Null_Statement then |
| return False; |
| end if; |
| |
| Next (Stm); |
| end loop; |
| |
| return True; |
| end Is_All_Null_Statements; |
| |
| -------------------------------------------------- |
| -- Is_Displacement_Of_Object_Or_Function_Result -- |
| -------------------------------------------------- |
| |
| function Is_Displacement_Of_Object_Or_Function_Result |
| (Obj_Id : Entity_Id) return Boolean |
| is |
| function Is_Controlled_Function_Call (N : Node_Id) return Boolean; |
| -- Determine if particular node denotes a controlled function call |
| |
| function Is_Displace_Call (N : Node_Id) return Boolean; |
| -- Determine whether a particular node is a call to Ada.Tags.Displace. |
| -- The call might be nested within other actions such as conversions. |
| |
| function Is_Source_Object (N : Node_Id) return Boolean; |
| -- Determine whether a particular node denotes a source object |
| |
| --------------------------------- |
| -- Is_Controlled_Function_Call -- |
| --------------------------------- |
| |
| function Is_Controlled_Function_Call (N : Node_Id) return Boolean is |
| Expr : Node_Id := Original_Node (N); |
| |
| begin |
| if Nkind (Expr) = N_Function_Call then |
| Expr := Name (Expr); |
| end if; |
| |
| -- The function call may appear in object.operation format |
| |
| if Nkind (Expr) = N_Selected_Component then |
| Expr := Selector_Name (Expr); |
| end if; |
| |
| return |
| Nkind_In (Expr, N_Expanded_Name, N_Identifier) |
| and then Ekind (Entity (Expr)) = E_Function |
| and then Needs_Finalization (Etype (Entity (Expr))); |
| end Is_Controlled_Function_Call; |
| |
| ---------------------- |
| -- Is_Displace_Call -- |
| ---------------------- |
| |
| function Is_Displace_Call (N : Node_Id) return Boolean is |
| Call : Node_Id := N; |
| |
| begin |
| -- Strip various actions which may precede a call to Displace |
| |
| loop |
| if Nkind (Call) = N_Explicit_Dereference then |
| Call := Prefix (Call); |
| |
| elsif Nkind_In (Call, N_Type_Conversion, |
| N_Unchecked_Type_Conversion) |
| then |
| Call := Expression (Call); |
| |
| else |
| exit; |
| end if; |
| end loop; |
| |
| return |
| Present (Call) |
| and then Nkind (Call) = N_Function_Call |
| and then Is_RTE (Entity (Name (Call)), RE_Displace); |
| end Is_Displace_Call; |
| |
| ---------------------- |
| -- Is_Source_Object -- |
| ---------------------- |
| |
| function Is_Source_Object (N : Node_Id) return Boolean is |
| begin |
| return |
| Present (N) |
| and then Nkind (N) in N_Has_Entity |
| and then Is_Object (Entity (N)) |
| and then Comes_From_Source (N); |
| end Is_Source_Object; |
| |
| -- Local variables |
| |
| Decl : constant Node_Id := Parent (Obj_Id); |
| Obj_Typ : constant Entity_Id := Base_Type (Etype (Obj_Id)); |
| Orig_Decl : constant Node_Id := Original_Node (Decl); |
| |
| -- Start of processing for Is_Displacement_Of_Object_Or_Function_Result |
| |
| begin |
| -- Case 1: |
| |
| -- Obj : CW_Type := Function_Call (...); |
| |
| -- rewritten into: |
| |
| -- Tmp : ... := Function_Call (...)'reference; |
| -- Obj : CW_Type renames (... Ada.Tags.Displace (Tmp)); |
| |
| -- where the return type of the function and the class-wide type require |
| -- dispatch table pointer displacement. |
| |
| -- Case 2: |
| |
| -- Obj : CW_Type := Src_Obj; |
| |
| -- rewritten into: |
| |
| -- Obj : CW_Type renames (... Ada.Tags.Displace (Src_Obj)); |
| |
| -- where the type of the source object and the class-wide type require |
| -- dispatch table pointer displacement. |
| |
| return |
| Nkind (Decl) = N_Object_Renaming_Declaration |
| and then Nkind (Orig_Decl) = N_Object_Declaration |
| and then Comes_From_Source (Orig_Decl) |
| and then Is_Class_Wide_Type (Obj_Typ) |
| and then Is_Displace_Call (Renamed_Object (Obj_Id)) |
| and then |
| (Is_Controlled_Function_Call (Expression (Orig_Decl)) |
| or else Is_Source_Object (Expression (Orig_Decl))); |
| end Is_Displacement_Of_Object_Or_Function_Result; |
| |
| ------------------------------ |
| -- Is_Finalizable_Transient -- |
| ------------------------------ |
| |
| function Is_Finalizable_Transient |
| (Decl : Node_Id; |
| Rel_Node : Node_Id) return Boolean |
| is |
| Obj_Id : constant Entity_Id := Defining_Identifier (Decl); |
| Obj_Typ : constant Entity_Id := Base_Type (Etype (Obj_Id)); |
| Desig : Entity_Id := Obj_Typ; |
| |
| function Initialized_By_Access (Trans_Id : Entity_Id) return Boolean; |
| -- Determine whether transient object Trans_Id is initialized either |
| -- by a function call which returns an access type or simply renames |
| -- another pointer. |
| |
| function Initialized_By_Aliased_BIP_Func_Call |
| (Trans_Id : Entity_Id) return Boolean; |
| -- Determine whether transient object Trans_Id is initialized by a |
| -- build-in-place function call where the BIPalloc parameter is of |
| -- value 1 and BIPaccess is not null. This case creates an aliasing |
| -- between the returned value and the value denoted by BIPaccess. |
| |
| function Is_Aliased |
| (Trans_Id : Entity_Id; |
| First_Stmt : Node_Id) return Boolean; |
| -- Determine whether transient object Trans_Id has been renamed or |
| -- aliased through 'reference in the statement list starting from |
| -- First_Stmt. |
| |
| function Is_Allocated (Trans_Id : Entity_Id) return Boolean; |
| -- Determine whether transient object Trans_Id is allocated on the heap |
| |
| function Is_Iterated_Container |
| (Trans_Id : Entity_Id; |
| First_Stmt : Node_Id) return Boolean; |
| -- Determine whether transient object Trans_Id denotes a container which |
| -- is in the process of being iterated in the statement list starting |
| -- from First_Stmt. |
| |
| --------------------------- |
| -- Initialized_By_Access -- |
| --------------------------- |
| |
| function Initialized_By_Access (Trans_Id : Entity_Id) return Boolean is |
| Expr : constant Node_Id := Expression (Parent (Trans_Id)); |
| |
| begin |
| return |
| Present (Expr) |
| and then Nkind (Expr) /= N_Reference |
| and then Is_Access_Type (Etype (Expr)); |
| end Initialized_By_Access; |
| |
| ------------------------------------------ |
| -- Initialized_By_Aliased_BIP_Func_Call -- |
| ------------------------------------------ |
| |
| function Initialized_By_Aliased_BIP_Func_Call |
| (Trans_Id : Entity_Id) return Boolean |
| is |
| Call : Node_Id := Expression (Parent (Trans_Id)); |
| |
| begin |
| -- Build-in-place calls usually appear in 'reference format |
| |
| if Nkind (Call) = N_Reference then |
| Call := Prefix (Call); |
| end if; |
| |
| if Is_Build_In_Place_Function_Call (Call) then |
| declare |
| Access_Nam : Name_Id := No_Name; |
| Access_OK : Boolean := False; |
| Actual : Node_Id; |
| Alloc_Nam : Name_Id := No_Name; |
| Alloc_OK : Boolean := False; |
| Formal : Node_Id; |
| Func_Id : Entity_Id; |
| Param : Node_Id; |
| |
| begin |
| -- Examine all parameter associations of the function call |
| |
| Param := First (Parameter_Associations (Call)); |
| while Present (Param) loop |
| if Nkind (Param) = N_Parameter_Association |
| and then Nkind (Selector_Name (Param)) = N_Identifier |
| then |
| Actual := Explicit_Actual_Parameter (Param); |
| Formal := Selector_Name (Param); |
| |
| -- Construct the names of formals BIPaccess and BIPalloc |
| -- using the function name retrieved from an arbitrary |
| -- formal. |
| |
| if Access_Nam = No_Name |
| and then Alloc_Nam = No_Name |
| and then Present (Entity (Formal)) |
| then |
| Func_Id := Scope (Entity (Formal)); |
| |
| Access_Nam := |
| New_External_Name (Chars (Func_Id), |
| BIP_Formal_Suffix (BIP_Object_Access)); |
| |
| Alloc_Nam := |
| New_External_Name (Chars (Func_Id), |
| BIP_Formal_Suffix (BIP_Alloc_Form)); |
| end if; |
| |
| -- A match for BIPaccess => Temp has been found |
| |
| if Chars (Formal) = Access_Nam |
| and then Nkind (Actual) /= N_Null |
| then |
| Access_OK := True; |
| end if; |
| |
| -- A match for BIPalloc => 1 has been found |
| |
| if Chars (Formal) = Alloc_Nam |
| and then Nkind (Actual) = N_Integer_Literal |
| and then Intval (Actual) = Uint_1 |
| then |
| Alloc_OK := True; |
| end if; |
| end if; |
| |
| Next (Param); |
| end loop; |
| |
| return Access_OK and Alloc_OK; |
| end; |
| end if; |
| |
| return False; |
| end Initialized_By_Aliased_BIP_Func_Call; |
| |
| ---------------- |
| -- Is_Aliased -- |
| ---------------- |
| |
| function Is_Aliased |
| (Trans_Id : Entity_Id; |
| First_Stmt : Node_Id) return Boolean |
| is |
| function Find_Renamed_Object (Ren_Decl : Node_Id) return Entity_Id; |
| -- Given an object renaming declaration, retrieve the entity of the |
| -- renamed name. Return Empty if the renamed name is anything other |
| -- than a variable or a constant. |
| |
| ------------------------- |
| -- Find_Renamed_Object -- |
| ------------------------- |
| |
| function Find_Renamed_Object (Ren_Decl : Node_Id) return Entity_Id is |
| Ren_Obj : Node_Id := Empty; |
| |
| function Find_Object (N : Node_Id) return Traverse_Result; |
| -- Try to detect an object which is either a constant or a |
| -- variable. |
| |
| ----------------- |
| -- Find_Object -- |
| ----------------- |
| |
| function Find_Object (N : Node_Id) return Traverse_Result is |
| begin |
| -- Stop the search once a constant or a variable has been |
| -- detected. |
| |
| if Nkind (N) = N_Identifier |
| and then Present (Entity (N)) |
| and then Ekind_In (Entity (N), E_Constant, E_Variable) |
| then |
| Ren_Obj := Entity (N); |
| return Abandon; |
| end if; |
| |
| return OK; |
| end Find_Object; |
| |
| procedure Search is new Traverse_Proc (Find_Object); |
| |
| -- Local variables |
| |
| Typ : constant Entity_Id := Etype (Defining_Identifier (Ren_Decl)); |
| |
| -- Start of processing for Find_Renamed_Object |
| |
| begin |
| -- Actions related to dispatching calls may appear as renamings of |
| -- tags. Do not process this type of renaming because it does not |
| -- use the actual value of the object. |
| |
| if not Is_RTE (Typ, RE_Tag_Ptr) then |
| Search (Name (Ren_Decl)); |
| end if; |
| |
| return Ren_Obj; |
| end Find_Renamed_Object; |
| |
| -- Local variables |
| |
| Expr : Node_Id; |
| Ren_Obj : Entity_Id; |
| Stmt : Node_Id; |
| |
| -- Start of processing for Is_Aliased |
| |
| begin |
| Stmt := First_Stmt; |
| while Present (Stmt) loop |
| if Nkind (Stmt) = N_Object_Declaration then |
| Expr := Expression (Stmt); |
| |
| if Present (Expr) |
| and then Nkind (Expr) = N_Reference |
| and then Nkind (Prefix (Expr)) = N_Identifier |
| and then Entity (Prefix (Expr)) = Trans_Id |
| then |
| return True; |
| end if; |
| |
| elsif Nkind (Stmt) = N_Object_Renaming_Declaration then |
| Ren_Obj := Find_Renamed_Object (Stmt); |
| |
| if Present (Ren_Obj) and then Ren_Obj = Trans_Id then |
| return True; |
| end if; |
| end if; |
| |
| Next (Stmt); |
| end loop; |
| |
| return False; |
| end Is_Aliased; |
| |
| ------------------ |
| -- Is_Allocated -- |
| ------------------ |
| |
| function Is_Allocated (Trans_Id : Entity_Id) return Boolean is |
| Expr : constant Node_Id := Expression (Parent (Trans_Id)); |
| begin |
| return |
| Is_Access_Type (Etype (Trans_Id)) |
| and then Present (Expr) |
| and then Nkind (Expr) = N_Allocator; |
| end Is_Allocated; |
| |
| --------------------------- |
| -- Is_Iterated_Container -- |
| --------------------------- |
| |
| function Is_Iterated_Container |
| (Trans_Id : Entity_Id; |
| First_Stmt : Node_Id) return Boolean |
| is |
| Aspect : Node_Id; |
| Call : Node_Id; |
| Iter : Entity_Id; |
| Param : Node_Id; |
| Stmt : Node_Id; |
| Typ : Entity_Id; |
| |
| begin |
| -- It is not possible to iterate over containers in non-Ada 2012 code |
| |
| if Ada_Version < Ada_2012 then |
| return False; |
| end if; |
| |
| Typ := Etype (Trans_Id); |
| |
| -- Handle access type created for secondary stack use |
| |
| if Is_Access_Type (Typ) then |
| Typ := Designated_Type (Typ); |
| end if; |
| |
| -- Look for aspect Default_Iterator |
| |
| if Has_Aspects (Parent (Typ)) then |
| Aspect := Find_Aspect (Typ, Aspect_Default_Iterator); |
| |
| if Present (Aspect) then |
| Iter := Entity (Aspect); |
| |
| -- Examine the statements following the container object and |
| -- look for a call to the default iterate routine where the |
| -- first parameter is the transient. Such a call appears as: |
| |
| -- It : Access_To_CW_Iterator := |
| -- Iterate (Tran_Id.all, ...)'reference; |
| |
| Stmt := First_Stmt; |
| while Present (Stmt) loop |
| |
| -- Detect an object declaration which is initialized by a |
| -- secondary stack function call. |
| |
| if Nkind (Stmt) = N_Object_Declaration |
| and then Present (Expression (Stmt)) |
| and then Nkind (Expression (Stmt)) = N_Reference |
| and then Nkind (Prefix (Expression (Stmt))) = |
| N_Function_Call |
| then |
| Call := Prefix (Expression (Stmt)); |
| |
| -- The call must invoke the default iterate routine of |
| -- the container and the transient object must appear as |
| -- the first actual parameter. Skip any calls whose names |
| -- are not entities. |
| |
| if Is_Entity_Name (Name (Call)) |
| and then Entity (Name (Call)) = Iter |
| and then Present (Parameter_Associations (Call)) |
| then |
| Param := First (Parameter_Associations (Call)); |
| |
| if Nkind (Param) = N_Explicit_Dereference |
| and then Entity (Prefix (Param)) = Trans_Id |
| then |
| return True; |
| end if; |
| end if; |
| end if; |
| |
| Next (Stmt); |
| end loop; |
| end if; |
| end if; |
| |
| return False; |
| end Is_Iterated_Container; |
| |
| -- Start of processing for Is_Finalizable_Transient |
| |
| begin |
| -- Handle access types |
| |
| if Is_Access_Type (Desig) then |
| Desig := Available_View (Designated_Type (Desig)); |
| end if; |
| |
| return |
| Ekind_In (Obj_Id, E_Constant, E_Variable) |
| and then Needs_Finalization (Desig) |
| and then Requires_Transient_Scope (Desig) |
| and then Nkind (Rel_Node) /= N_Simple_Return_Statement |
| |
| -- Do not consider renamed or 'reference-d transient objects because |
| -- the act of renaming extends the object's lifetime. |
| |
| and then not Is_Aliased (Obj_Id, Decl) |
| |
| -- Do not consider transient objects allocated on the heap since |
| -- they are attached to a finalization master. |
| |
| and then not Is_Allocated (Obj_Id) |
| |
| -- If the transient object is a pointer, check that it is not |
| -- initialized by a function which returns a pointer or acts as a |
| -- renaming of another pointer. |
| |
| and then |
| (not Is_Access_Type (Obj_Typ) |
| or else not Initialized_By_Access (Obj_Id)) |
| |
| -- Do not consider transient objects which act as indirect aliases |
| -- of build-in-place function results. |
| |
| and then not Initialized_By_Aliased_BIP_Func_Call (Obj_Id) |
| |
| -- Do not consider conversions of tags to class-wide types |
| |
| and then not Is_Tag_To_Class_Wide_Conversion (Obj_Id) |
| |
| -- Do not consider containers in the context of iterator loops. Such |
| -- transient objects must exist for as long as the loop is around, |
| -- otherwise any operation carried out by the iterator will fail. |
| |
| and then not Is_Iterated_Container (Obj_Id, Decl); |
| end Is_Finalizable_Transient; |
| |
| --------------------------------- |
| -- Is_Fully_Repped_Tagged_Type -- |
| --------------------------------- |
| |
| function Is_Fully_Repped_Tagged_Type (T : Entity_Id) return Boolean is |
| U : constant Entity_Id := Underlying_Type (T); |
| Comp : Entity_Id; |
| |
| begin |
| if No (U) or else not Is_Tagged_Type (U) then |
| return False; |
| elsif Has_Discriminants (U) then |
| return False; |
| elsif not Has_Specified_Layout (U) then |
| return False; |
| end if; |
| |
| -- Here we have a tagged type, see if it has any unlayed out fields |
| -- other than a possible tag and parent fields. If so, we return False. |
| |
| Comp := First_Component (U); |
| while Present (Comp) loop |
| if not Is_Tag (Comp) |
| and then Chars (Comp) /= Name_uParent |
| and then No (Component_Clause (Comp)) |
| then |
| return False; |
| else |
| Next_Component (Comp); |
| end if; |
| end loop; |
| |
| -- All components are layed out |
| |
| return True; |
| end Is_Fully_Repped_Tagged_Type; |
| |
| ---------------------------------- |
| -- Is_Library_Level_Tagged_Type -- |
| ---------------------------------- |
| |
| function Is_Library_Level_Tagged_Type (Typ : Entity_Id) return Boolean is |
| begin |
| return Is_Tagged_Type (Typ) and then Is_Library_Level_Entity (Typ); |
| end Is_Library_Level_Tagged_Type; |
| |
| -------------------------- |
| -- Is_Non_BIP_Func_Call -- |
| -------------------------- |
| |
| function Is_Non_BIP_Func_Call (Expr : Node_Id) return Boolean is |
| begin |
| -- The expected call is of the format |
| -- |
| -- Func_Call'reference |
| |
| return |
| Nkind (Expr) = N_Reference |
| and then Nkind (Prefix (Expr)) = N_Function_Call |
| and then not Is_Build_In_Place_Function_Call (Prefix (Expr)); |
| end Is_Non_BIP_Func_Call; |
| |
| ---------------------------------- |
| -- Is_Possibly_Unaligned_Object -- |
| ---------------------------------- |
| |
| function Is_Possibly_Unaligned_Object (N : Node_Id) return Boolean is |
| T : constant Entity_Id := Etype (N); |
| |
| begin |
| -- If renamed object, apply test to underlying object |
| |
| if Is_Entity_Name (N) |
| and then Is_Object (Entity (N)) |
| and then Present (Renamed_Object (Entity (N))) |
| then |
| return Is_Possibly_Unaligned_Object (Renamed_Object (Entity (N))); |
| end if; |
| |
| -- Tagged and controlled types and aliased types are always aligned, as |
| -- are concurrent types. |
| |
| if Is_Aliased (T) |
| or else Has_Controlled_Component (T) |
| or else Is_Concurrent_Type (T) |
| or else Is_Tagged_Type (T) |
| or else Is_Controlled (T) |
| then |
| return False; |
| end if; |
| |
| -- If this is an element of a packed array, may be unaligned |
| |
| if Is_Ref_To_Bit_Packed_Array (N) then |
| return True; |
| end if; |
| |
| -- Case of indexed component reference: test whether prefix is unaligned |
| |
| if Nkind (N) = N_Indexed_Component then |
| return Is_Possibly_Unaligned_Object (Prefix (N)); |
| |
| -- Case of selected component reference |
| |
| elsif Nkind (N) = N_Selected_Component then |
| declare |
| P : constant Node_Id := Prefix (N); |
| C : constant Entity_Id := Entity (Selector_Name (N)); |
| M : Nat; |
| S : Nat; |
| |
| begin |
| -- If component reference is for an array with non-static bounds, |
| -- then it is always aligned: we can only process unaligned arrays |
| -- with static bounds (more precisely compile time known bounds). |
| |
| if Is_Array_Type (T) |
| and then not Compile_Time_Known_Bounds (T) |
| then |
| return False; |
| end if; |
| |
| -- If component is aliased, it is definitely properly aligned |
| |
| if Is_Aliased (C) then |
| return False; |
| end if; |
| |
| -- If component is for a type implemented as a scalar, and the |
| -- record is packed, and the component is other than the first |
| -- component of the record, then the component may be unaligned. |
| |
| if Is_Packed (Etype (P)) |
| and then Represented_As_Scalar (Etype (C)) |
| and then First_Entity (Scope (C)) /= C |
| then |
| return True; |
| end if; |
| |
| -- Compute maximum possible alignment for T |
| |
| -- If alignment is known, then that settles things |
| |
| if Known_Alignment (T) then |
| M := UI_To_Int (Alignment (T)); |
| |
| -- If alignment is not known, tentatively set max alignment |
| |
| else |
| M := Ttypes.Maximum_Alignment; |
| |
| -- We can reduce this if the Esize is known since the default |
| -- alignment will never be more than the smallest power of 2 |
| -- that does not exceed this Esize value. |
| |
| if Known_Esize (T) then |
| S := UI_To_Int (Esize (T)); |
| |
| while (M / 2) >= S loop |
| M := M / 2; |
| end loop; |
| end if; |
| end if; |
| |
| -- The following code is historical, it used to be present but it |
| -- is too cautious, because the front-end does not know the proper |
| -- default alignments for the target. Also, if the alignment is |
| -- not known, the front end can't know in any case! If a copy is |
| -- needed, the back-end will take care of it. This whole section |
| -- including this comment can be removed later ??? |
| |
| -- If the component reference is for a record that has a specified |
| -- alignment, and we either know it is too small, or cannot tell, |
| -- then the component may be unaligned. |
| |
| -- What is the following commented out code ??? |
| |
| -- if Known_Alignment (Etype (P)) |
| -- and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment |
| -- and then M > Alignment (Etype (P)) |
| -- then |
| -- return True; |
| -- end if; |
| |
| -- Case of component clause present which may specify an |
| -- unaligned position. |
| |
| if Present (Component_Clause (C)) then |
| |
| -- Otherwise we can do a test to make sure that the actual |
| -- start position in the record, and the length, are both |
| -- consistent with the required alignment. If not, we know |
| -- that we are unaligned. |
| |
| declare |
| Align_In_Bits : constant Nat := M * System_Storage_Unit; |
| begin |
| if Component_Bit_Offset (C) mod Align_In_Bits /= 0 |
| or else Esize (C) mod Align_In_Bits /= 0 |
| then |
| return True; |
| end if; |
| end; |
| end if; |
| |
| -- Otherwise, for a component reference, test prefix |
| |
| return Is_Possibly_Unaligned_Object (P); |
| end; |
| |
| -- If not a component reference, must be aligned |
| |
| else |
| return False; |
| end if; |
| end Is_Possibly_Unaligned_Object; |
| |
| --------------------------------- |
| -- Is_Possibly_Unaligned_Slice -- |
| --------------------------------- |
| |
| function Is_Possibly_Unaligned_Slice (N : Node_Id) return Boolean is |
| begin |
| -- Go to renamed object |
| |
| if Is_Entity_Name (N) |
| and then Is_Object (Entity (N)) |
| and then Present (Renamed_Object (Entity (N))) |
| then |
| return Is_Possibly_Unaligned_Slice (Renamed_Object (Entity (N))); |
| end if; |
| |
| -- The reference must be a slice |
| |
| if Nkind (N) /= N_Slice then |
| return False; |
| end if; |
| |
| -- Always assume the worst for a nested record component with a |
| -- component clause, which gigi/gcc does not appear to handle well. |
| -- It is not clear why this special test is needed at all ??? |
| |
| if Nkind (Prefix (N)) = N_Selected_Component |
| and then Nkind (Prefix (Prefix (N))) = N_Selected_Component |
| and then |
| Present (Component_Clause (Entity (Selector_Name (Prefix (N))))) |
| then |
| return True; |
| end if; |
| |
| -- We only need to worry if the target has strict alignment |
| |
| if not Target_Strict_Alignment then |
| return False; |
| end if; |
| |
| -- If it is a slice, then look at the array type being sliced |
| |
| declare |
| Sarr : constant Node_Id := Prefix (N); |
| -- Prefix of the slice, i.e. the array being sliced |
| |
| Styp : constant Entity_Id := Etype (Prefix (N)); |
| -- Type of the array being sliced |
| |
| Pref : Node_Id; |
| Ptyp : Entity_Id; |
| |
| begin |
| -- The problems arise if the array object that is being sliced |
| -- is a component of a record or array, and we cannot guarantee |
| -- the alignment of the array within its containing object. |
| |
| -- To investigate this, we look at successive prefixes to see |
| -- if we have a worrisome indexed or selected component. |
| |
| Pref := Sarr; |
| loop |
| -- Case of array is part of an indexed component reference |
| |
| if Nkind (Pref) = N_Indexed_Component then |
| Ptyp := Etype (Prefix (Pref)); |
| |
| -- The only problematic case is when the array is packed, in |
| -- which case we really know nothing about the alignment of |
| -- individual components. |
| |
| if Is_Bit_Packed_Array (Ptyp) then |
| return True; |
| end if; |
| |
| -- Case of array is part of a selected component reference |
| |
| elsif Nkind (Pref) = N_Selected_Component then |
| Ptyp := Etype (Prefix (Pref)); |
| |
| -- We are definitely in trouble if the record in question |
| -- has an alignment, and either we know this alignment is |
| -- inconsistent with the alignment of the slice, or we don't |
| -- know what the alignment of the slice should be. |
| |
| if Known_Alignment (Ptyp) |
| and then (Unknown_Alignment (Styp) |
| or else Alignment (Styp) > Alignment (Ptyp)) |
| then |
| return True; |
| end if; |
| |
| -- We are in potential trouble if the record type is packed. |
| -- We could special case when we know that the array is the |
| -- first component, but that's not such a simple case ??? |
| |
| if Is_Packed (Ptyp) then |
| return True; |
| end if; |
| |
| -- We are in trouble if there is a component clause, and |
| -- either we do not know the alignment of the slice, or |
| -- the alignment of the slice is inconsistent with the |
| -- bit position specified by the component clause. |
| |
| declare |
| Field : constant Entity_Id := Entity (Selector_Name (Pref)); |
| begin |
| if Present (Component_Clause (Field)) |
| and then |
| (Unknown_Alignment (Styp) |
| or else |
| (Component_Bit_Offset (Field) mod |
| (System_Storage_Unit * Alignment (Styp))) /= 0) |
| then |
| return True; |
| end if; |
| end; |
| |
| -- For cases other than selected or indexed components we know we |
| -- are OK, since no issues arise over alignment. |
| |
| else |
| return False; |
| end if; |
| |
| -- We processed an indexed component or selected component |
| -- reference that looked safe, so keep checking prefixes. |
| |
| Pref := Prefix (Pref); |
| end loop; |
| end; |
| end Is_Possibly_Unaligned_Slice; |
| |
| ------------------------------- |
| -- Is_Related_To_Func_Return -- |
| ------------------------------- |
| |
| function Is_Related_To_Func_Return (Id : Entity_Id) return Boolean is |
| Expr : constant Node_Id := Related_Expression (Id); |
| begin |
| return |
| Present (Expr) |
| and then Nkind (Expr) = N_Explicit_Dereference |
| and then Nkind (Parent (Expr)) = N_Simple_Return_Statement; |
| end Is_Related_To_Func_Return; |
| |
| -------------------------------- |
| -- Is_Ref_To_Bit_Packed_Array -- |
| -------------------------------- |
| |
| function Is_Ref_To_Bit_Packed_Array (N : Node_Id) return Boolean is |
| Result : Boolean; |
| Expr : Node_Id; |
| |
| begin |
| if Is_Entity_Name (N) |
| and then Is_Object (Entity (N)) |
| and then Present (Renamed_Object (Entity (N))) |
| then |
| return Is_Ref_To_Bit_Packed_Array (Renamed_Object (Entity (N))); |
| end if; |
| |
| if Nkind_In (N, N_Indexed_Component, N_Selected_Component) then |
| if Is_Bit_Packed_Array (Etype (Prefix (N))) then |
| Result := True; |
| else |
| Result := Is_Ref_To_Bit_Packed_Array (Prefix (N)); |
| end if; |
| |
| if Result and then Nkind (N) = N_Indexed_Component then |
| Expr := First (Expressions (N)); |
| while Present (Expr) loop |
| Force_Evaluation (Expr); |
| Next (Expr); |
| end loop; |
| end if; |
| |
| return Result; |
| |
| else |
| return False; |
| end if; |
| end Is_Ref_To_Bit_Packed_Array; |
| |
| -------------------------------- |
| -- Is_Ref_To_Bit_Packed_Slice -- |
| -------------------------------- |
| |
| function Is_Ref_To_Bit_Packed_Slice (N : Node_Id) return Boolean is |
| begin |
| if Nkind (N) = N_Type_Conversion then |
| return Is_Ref_To_Bit_Packed_Slice (Expression (N)); |
| |
| elsif Is_Entity_Name (N) |
| and then Is_Object (Entity (N)) |
| and then Present (Renamed_Object (Entity (N))) |
| then |
| return Is_Ref_To_Bit_Packed_Slice (Renamed_Object (Entity (N))); |
| |
| elsif Nkind (N) = N_Slice |
| and then Is_Bit_Packed_Array (Etype (Prefix (N))) |
| then |
| return True; |
| |
| elsif Nkind_In (N, N_Indexed_Component, N_Selected_Component) then |
| return Is_Ref_To_Bit_Packed_Slice (Prefix (N)); |
| |
| else |
| return False; |
| end if; |
| end Is_Ref_To_Bit_Packed_Slice; |
| |
| ----------------------- |
| -- Is_Renamed_Object -- |
| ----------------------- |
| |
| function Is_Renamed_Object (N : Node_Id) return Boolean is |
| Pnod : constant Node_Id := Parent (N); |
| Kind : constant Node_Kind := Nkind (Pnod); |
| begin |
| if Kind = N_Object_Renaming_Declaration then |
| return True; |
| elsif Nkind_In (Kind, N_Indexed_Component, N_Selected_Component) then |
| return Is_Renamed_Object (Pnod); |
| else |
| return False; |
| end if; |
| end Is_Renamed_Object; |
| |
| -------------------------------------- |
| -- Is_Secondary_Stack_BIP_Func_Call -- |
| -------------------------------------- |
| |
| function Is_Secondary_Stack_BIP_Func_Call (Expr : Node_Id) return Boolean is |
| Call : Node_Id := Expr; |
| |
| begin |
| -- Build-in-place calls usually appear in 'reference format. Note that |
| -- the accessibility check machinery may add an extra 'reference due to |
| -- side effect removal. |
| |
| while Nkind (Call) = N_Reference loop |
| Call := Prefix (Call); |
| end loop; |
| |
| if Nkind_In (Call, N_Qualified_Expression, |
| N_Unchecked_Type_Conversion) |
| then |
| Call := Expression (Call); |
| end if; |
| |
| if Is_Build_In_Place_Function_Call (Call) then |
| declare |
| Access_Nam : Name_Id := No_Name; |
| Actual : Node_Id; |
| Param : Node_Id; |
| Formal : Node_Id; |
| |
| begin |
| -- Examine all parameter associations of the function call |
| |
| Param := First (Parameter_Associations (Call)); |
| while Present (Param) loop |
| if Nkind (Param) = N_Parameter_Association |
| and then Nkind (Selector_Name (Param)) = N_Identifier |
| then |
| Formal := Selector_Name (Param); |
| Actual := Explicit_Actual_Parameter (Param); |
| |
| -- Construct the name of formal BIPalloc. It is much easier |
| -- to extract the name of the function using an arbitrary |
| -- formal's scope rather than the Name field of Call. |
| |
| if Access_Nam = No_Name |
| and then Present (Entity (Formal)) |
| then |
| Access_Nam := |
| New_External_Name |
| (Chars (Scope (Entity (Formal))), |
| BIP_Formal_Suffix (BIP_Alloc_Form)); |
| end if; |
| |
| -- A match for BIPalloc => 2 has been found |
| |
| if Chars (Formal) = Access_Nam |
| and then Nkind (Actual) = N_Integer_Literal |
| and then Intval (Actual) = Uint_2 |
| then |
| return True; |
| end if; |
| end if; |
| |
| Next (Param); |
| end loop; |
| end; |
| end if; |
| |
| return False; |
| end Is_Secondary_Stack_BIP_Func_Call; |
| |
| ------------------------------------- |
| -- Is_Tag_To_Class_Wide_Conversion -- |
| ------------------------------------- |
| |
| function Is_Tag_To_Class_Wide_Conversion |
| (Obj_Id : Entity_Id) return Boolean |
| is |
| Expr : constant Node_Id := Expression (Parent (Obj_Id)); |
| |
| begin |
| return |
| Is_Class_Wide_Type (Etype (Obj_Id)) |
| and then Present (Expr) |
| and then Nkind (Expr) = N_Unchecked_Type_Conversion |
| and then Etype (Expression (Expr)) = RTE (RE_Tag); |
| end Is_Tag_To_Class_Wide_Conversion; |
| |
| ---------------------------- |
| -- Is_Untagged_Derivation -- |
| ---------------------------- |
| |
| function Is_Untagged_Derivation (T : Entity_Id) return Boolean is |
| begin |
| return (not Is_Tagged_Type (T) and then Is_Derived_Type (T)) |
| or else |
| (Is_Private_Type (T) and then Present (Full_View (T)) |
| and then not Is_Tagged_Type (Full_View (T)) |
| and then Is_Derived_Type (Full_View (T)) |
| and then Etype (Full_View (T)) /= T); |
| end Is_Untagged_Derivation; |
| |
| --------------------------- |
| -- Is_Volatile_Reference -- |
| --------------------------- |
| |
| function Is_Volatile_Reference (N : Node_Id) return Boolean is |
| begin |
| if Nkind (N) in N_Has_Etype |
| and then Present (Etype (N)) |
| and then Treat_As_Volatile (Etype (N)) |
| then |
| return True; |
| |
| elsif Is_Entity_Name (N) then |
| return Treat_As_Volatile (Entity (N)); |
| |
| elsif Nkind (N) = N_Slice then |
| return Is_Volatile_Reference (Prefix (N)); |
| |
| elsif Nkind_In (N, N_Indexed_Component, N_Selected_Component) then |
| if (Is_Entity_Name (Prefix (N)) |
| and then Has_Volatile_Components (Entity (Prefix (N)))) |
| or else (Present (Etype (Prefix (N))) |
| and then Has_Volatile_Components (Etype (Prefix (N)))) |
| then |
| return True; |
| else |
| return Is_Volatile_Reference (Prefix (N)); |
| end if; |
| |
| else |
| return False; |
| end if; |
| end Is_Volatile_Reference; |
| |
| -------------------------- |
| -- Is_VM_By_Copy_Actual -- |
| -------------------------- |
| |
| function Is_VM_By_Copy_Actual (N : Node_Id) return Boolean is |
| begin |
| return VM_Target /= No_VM |
| and then (Nkind (N) = N_Slice |
| or else |
| (Nkind (N) = N_Identifier |
| and then Present (Renamed_Object (Entity (N))) |
| and then Nkind (Renamed_Object (Entity (N))) = |
| N_Slice)); |
| end Is_VM_By_Copy_Actual; |
| |
| -------------------- |
| -- Kill_Dead_Code -- |
| -------------------- |
| |
| procedure Kill_Dead_Code (N : Node_Id; Warn : Boolean := False) is |
| W : Boolean := Warn; |
| -- Set False if warnings suppressed |
| |
| begin |
| if Present (N) then |
| Remove_Warning_Messages (N); |
| |
| -- Generate warning if appropriate |
| |
| if W then |
| |
| -- We suppress the warning if this code is under control of an |
| -- if statement, whose condition is a simple identifier, and |
| -- either we are in an instance, or warnings off is set for this |
| -- identifier. The reason for killing it in the instance case is |
| -- that it is common and reasonable for code to be deleted in |
| -- instances for various reasons. |
| |
| if Nkind (Parent (N)) = N_If_Statement then |
| declare |
| C : constant Node_Id := Condition (Parent (N)); |
| begin |
| if Nkind (C) = N_Identifier |
| and then |
| (In_Instance |
| or else (Present (Entity (C)) |
| and then Has_Warnings_Off (Entity (C)))) |
| then |
| W := False; |
| end if; |
| end; |
| end if; |
| |
| -- Generate warning if not suppressed |
| |
| if W then |
| Error_Msg_F |
| ("?t?this code can never be executed and has been deleted!", |
| N); |
| end if; |
| end if; |
| |
| -- Recurse into block statements and bodies to process declarations |
| -- and statements. |
| |
| if Nkind (N) = N_Block_Statement |
| or else Nkind (N) = N_Subprogram_Body |
| or else Nkind (N) = N_Package_Body |
| then |
| Kill_Dead_Code (Declarations (N), False); |
| Kill_Dead_Code (Statements (Handled_Statement_Sequence (N))); |
| |
| if Nkind (N) = N_Subprogram_Body then |
| Set_Is_Eliminated (Defining_Entity (N)); |
| end if; |
| |
| elsif Nkind (N) = N_Package_Declaration then |
| Kill_Dead_Code (Visible_Declarations (Specification (N))); |
| Kill_Dead_Code (Private_Declarations (Specification (N))); |
| |
| -- ??? After this point, Delete_Tree has been called on all |
| -- declarations in Specification (N), so references to entities |
| -- therein look suspicious. |
| |
| declare |
| E : Entity_Id := First_Entity (Defining_Entity (N)); |
| begin |
| while Present (E) loop |
| if Ekind (E) = E_Operator then |
| Set_Is_Eliminated (E); |
| end if; |
| |
| Next_Entity (E); |
| end loop; |
| end; |
| |
| -- Recurse into composite statement to kill individual statements in |
| -- particular instantiations. |
| |
| elsif Nkind (N) = N_If_Statement then |
| Kill_Dead_Code (Then_Statements (N)); |
| Kill_Dead_Code (Elsif_Parts (N)); |
| Kill_Dead_Code (Else_Statements (N)); |
| |
| elsif Nkind (N) = N_Loop_Statement then |
| Kill_Dead_Code (Statements (N)); |
| |
| elsif Nkind (N) = N_Case_Statement then |
| declare |
| Alt : Node_Id; |
| begin |
| Alt := First (Alternatives (N)); |
| while Present (Alt) loop |
| Kill_Dead_Code (Statements (Alt)); |
| Next (Alt); |
| end loop; |
| end; |
| |
| elsif Nkind (N) = N_Case_Statement_Alternative then |
| Kill_Dead_Code (Statements (N)); |
| |
| -- Deal with dead instances caused by deleting instantiations |
| |
| elsif Nkind (N) in N_Generic_Instantiation then |
| Remove_Dead_Instance (N); |
| end if; |
| end if; |
| end Kill_Dead_Code; |
| |
| -- Case where argument is a list of nodes to be killed |
| |
| procedure Kill_Dead_Code (L : List_Id; Warn : Boolean := False) is |
| N : Node_Id; |
| W : Boolean; |
| begin |
| W := Warn; |
| if Is_Non_Empty_List (L) then |
| N := First (L); |
| while Present (N) loop |
| Kill_Dead_Code (N, W); |
| W := False; |
| Next (N); |
| end loop; |
| end if; |
| end Kill_Dead_Code; |
| |
| ------------------------ |
| -- Known_Non_Negative -- |
| ------------------------ |
| |
| function Known_Non_Negative (Opnd : Node_Id) return Boolean is |
| begin |
| if Is_OK_Static_Expression (Opnd) and then Expr_Value (Opnd) >= 0 then |
| return True; |
| |
| else |
| declare |
| Lo : constant Node_Id := Type_Low_Bound (Etype (Opnd)); |
| begin |
| return |
| Is_OK_Static_Expression (Lo) and then Expr_Value (Lo) >= 0; |
| end; |
| end if; |
| end Known_Non_Negative; |
| |
| -------------------- |
| -- Known_Non_Null -- |
| -------------------- |
| |
| function Known_Non_Null (N : Node_Id) return Boolean is |
| begin |
| -- Checks for case where N is an entity reference |
| |
| if Is_Entity_Name (N) and then Present (Entity (N)) then |
| declare |
| E : constant Entity_Id := Entity (N); |
| Op : Node_Kind; |
| Val : Node_Id; |
| |
| begin |
| -- First check if we are in decisive conditional |
| |
| Get_Current_Value_Condition (N, Op, Val); |
| |
| if Known_Null (Val) then |
| if Op = N_Op_Eq then |
| return False; |
| elsif Op = N_Op_Ne then |
| return True; |
| end if; |
| end if; |
| |
| -- If OK to do replacement, test Is_Known_Non_Null flag |
| |
| if OK_To_Do_Constant_Replacement (E) then |
| return Is_Known_Non_Null (E); |
| |
| -- Otherwise if not safe to do replacement, then say so |
| |
| else |
| return False; |
| end if; |
| end; |
| |
| -- True if access attribute |
| |
| elsif Nkind (N) = N_Attribute_Reference |
| and then (Attribute_Name (N) = Name_Access |
| or else |
| Attribute_Name (N) = Name_Unchecked_Access |
| or else |
| Attribute_Name (N) = Name_Unrestricted_Access) |
| then |
| return True; |
| |
| -- True if allocator |
| |
| elsif Nkind (N) = N_Allocator then |
| return True; |
| |
| -- For a conversion, true if expression is known non-null |
| |
| elsif Nkind (N) = N_Type_Conversion then |
| return Known_Non_Null (Expression (N)); |
| |
| -- Above are all cases where the value could be determined to be |
| -- non-null. In all other cases, we don't know, so return False. |
| |
| else |
| return False; |
| end if; |
| end Known_Non_Null; |
| |
| ---------------- |
| -- Known_Null -- |
| ---------------- |
| |
| function Known_Null (N : Node_Id) return Boolean is |
| begin |
| -- Checks for case where N is an entity reference |
| |
| if Is_Entity_Name (N) and then Present (Entity (N)) then |
| declare |
| E : constant Entity_Id := Entity (N); |
| Op : Node_Kind; |
| Val : Node_Id; |
| |
| begin |
| -- Constant null value is for sure null |
| |
| if Ekind (E) = E_Constant |
| and then Known_Null (Constant_Value (E)) |
| then |
| return True; |
| end if; |
| |
| -- First check if we are in decisive conditional |
| |
| Get_Current_Value_Condition (N, Op, Val); |
| |
| if Known_Null (Val) then |
| if Op = N_Op_Eq then |
| return True; |
| elsif Op = N_Op_Ne then |
| return False; |
| end if; |
| end if; |
| |
| -- If OK to do replacement, test Is_Known_Null flag |
| |
| if OK_To_Do_Constant_Replacement (E) then |
| return Is_Known_Null (E); |
| |
| -- Otherwise if not safe to do replacement, then say so |
| |
| else |
| return False; |
| end if; |
| end; |
| |
| -- True if explicit reference to null |
| |
| elsif Nkind (N) = N_Null then |
| return True; |
| |
| -- For a conversion, true if expression is known null |
| |
| elsif Nkind (N) = N_Type_Conversion then |
| return Known_Null (Expression (N)); |
| |
| -- Above are all cases where the value could be determined to be null. |
| -- In all other cases, we don't know, so return False. |
| |
| else |
| return False; |
| end if; |
| end Known_Null; |
| |
| ----------------------------- |
| -- Make_CW_Equivalent_Type -- |
| ----------------------------- |
| |
| -- Create a record type used as an equivalent of any member of the class |
| -- which takes its size from exp. |
| |
| -- Generate the following code: |
| |
| -- type Equiv_T is record |
| -- _parent : T (List of discriminant constraints taken from Exp); |
| -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8); |
| -- end Equiv_T; |
| -- |
| -- ??? Note that this type does not guarantee same alignment as all |
| -- derived types |
| |
| function Make_CW_Equivalent_Type |
| (T : Entity_Id; |
| E : Node_Id) return Entity_Id |
| is |
| Loc : constant Source_Ptr := Sloc (E); |
| Root_Typ : constant Entity_Id := Root_Type (T); |
| List_Def : constant List_Id := Empty_List; |
| Comp_List : constant List_Id := New_List; |
| Equiv_Type : Entity_Id; |
| Range_Type : Entity_Id; |
| Str_Type : Entity_Id; |
| Constr_Root : Entity_Id; |
| Sizexpr : Node_Id; |
| |
| begin |
| -- If the root type is already constrained, there are no discriminants |
| -- in the expression. |
| |
| if not Has_Discriminants (Root_Typ) |
| or else Is_Constrained (Root_Typ) |
| then |
| Constr_Root := Root_Typ; |
| else |
| Constr_Root := Make_Temporary (Loc, 'R'); |
| |
| -- subtype cstr__n is T (List of discr constraints taken from Exp) |
| |
| Append_To (List_Def, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Constr_Root, |
| Subtype_Indication => Make_Subtype_From_Expr (E, Root_Typ))); |
| end if; |
| |
| -- Generate the range subtype declaration |
| |
| Range_Type := Make_Temporary (Loc, 'G'); |
| |
| if not Is_Interface (Root_Typ) then |
| |
| -- subtype rg__xx is |
| -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit |
| |
| Sizexpr := |
| Make_Op_Subtract (Loc, |
| Left_Opnd => |
| Make_Attribute_Reference (Loc, |
| Prefix => |
| OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)), |
| Attribute_Name => Name_Size), |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Prefix => New_Reference_To (Constr_Root, Loc), |
| Attribute_Name => Name_Object_Size)); |
| else |
| -- subtype rg__xx is |
| -- Storage_Offset range 1 .. Expr'size / Storage_Unit |
| |
| Sizexpr := |
| Make_Attribute_Reference (Loc, |
| Prefix => |
| OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)), |
| Attribute_Name => Name_Size); |
| end if; |
| |
| Set_Paren_Count (Sizexpr, 1); |
| |
| Append_To (List_Def, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Range_Type, |
| Subtype_Indication => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (RTE (RE_Storage_Offset), Loc), |
| Constraint => Make_Range_Constraint (Loc, |
| Range_Expression => |
| Make_Range (Loc, |
| Low_Bound => Make_Integer_Literal (Loc, 1), |
| High_Bound => |
| Make_Op_Divide (Loc, |
| Left_Opnd => Sizexpr, |
| Right_Opnd => Make_Integer_Literal (Loc, |
| Intval => System_Storage_Unit))))))); |
| |
| -- subtype str__nn is Storage_Array (rg__x); |
| |
| Str_Type := Make_Temporary (Loc, 'S'); |
| Append_To (List_Def, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Str_Type, |
| Subtype_Indication => |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (RTE (RE_Storage_Array), Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint (Loc, |
| Constraints => |
| New_List (New_Reference_To (Range_Type, Loc)))))); |
| |
| -- type Equiv_T is record |
| -- [ _parent : Tnn; ] |
| -- E : Str_Type; |
| -- end Equiv_T; |
| |
| Equiv_Type := Make_Temporary (Loc, 'T'); |
| Set_Ekind (Equiv_Type, E_Record_Type); |
| Set_Parent_Subtype (Equiv_Type, Constr_Root); |
| |
| -- Set Is_Class_Wide_Equivalent_Type very early to trigger the special |
| -- treatment for this type. In particular, even though _parent's type |
| -- is a controlled type or contains controlled components, we do not |
| -- want to set Has_Controlled_Component on it to avoid making it gain |
| -- an unwanted _controller component. |
| |
| Set_Is_Class_Wide_Equivalent_Type (Equiv_Type); |
| |
| if not Is_Interface (Root_Typ) then |
| Append_To (Comp_List, |
| Make_Component_Declaration (Loc, |
| Defining_Identifier => |
| Make_Defining_Identifier (Loc, Name_uParent), |
| Component_Definition => |
| Make_Component_Definition (Loc, |
| Aliased_Present => False, |
| Subtype_Indication => New_Reference_To (Constr_Root, Loc)))); |
| end if; |
| |
| Append_To (Comp_List, |
| Make_Component_Declaration (Loc, |
| Defining_Identifier => Make_Temporary (Loc, 'C'), |
| Component_Definition => |
| Make_Component_Definition (Loc, |
| Aliased_Present => False, |
| Subtype_Indication => New_Reference_To (Str_Type, Loc)))); |
| |
| Append_To (List_Def, |
| Make_Full_Type_Declaration (Loc, |
| Defining_Identifier => Equiv_Type, |
| Type_Definition => |
| Make_Record_Definition (Loc, |
| Component_List => |
| Make_Component_List (Loc, |
| Component_Items => Comp_List, |
| Variant_Part => Empty)))); |
| |
| -- Suppress all checks during the analysis of the expanded code to avoid |
| -- the generation of spurious warnings under ZFP run-time. |
| |
| Insert_Actions (E, List_Def, Suppress => All_Checks); |
| return Equiv_Type; |
| end Make_CW_Equivalent_Type; |
| |
| ------------------------- |
| -- Make_Invariant_Call -- |
| ------------------------- |
| |
| function Make_Invariant_Call (Expr : Node_Id) return Node_Id is |
| Loc : constant Source_Ptr := Sloc (Expr); |
| Typ : constant Entity_Id := Etype (Expr); |
| |
| begin |
| pragma Assert |
| (Has_Invariants (Typ) and then Present (Invariant_Procedure (Typ))); |
| |
| if Check_Enabled (Name_Invariant) |
| or else |
| Check_Enabled (Name_Assertion) |
| then |
| return |
| Make_Procedure_Call_Statement (Loc, |
| Name => |
| New_Occurrence_Of (Invariant_Procedure (Typ), Loc), |
| Parameter_Associations => New_List (Relocate_Node (Expr))); |
| |
| else |
| return |
| Make_Null_Statement (Loc); |
| end if; |
| end Make_Invariant_Call; |
| |
| ------------------------ |
| -- Make_Literal_Range -- |
| ------------------------ |
| |
| function Make_Literal_Range |
| (Loc : Source_Ptr; |
| Literal_Typ : Entity_Id) return Node_Id |
| is |
| Lo : constant Node_Id := |
| New_Copy_Tree (String_Literal_Low_Bound (Literal_Typ)); |
| Index : constant Entity_Id := Etype (Lo); |
| |
| Hi : Node_Id; |
| Length_Expr : constant Node_Id := |
| Make_Op_Subtract (Loc, |
| Left_Opnd => |
| Make_Integer_Literal (Loc, |
| Intval => String_Literal_Length (Literal_Typ)), |
| Right_Opnd => |
| Make_Integer_Literal (Loc, 1)); |
| |
| begin |
| Set_Analyzed (Lo, False); |
| |
| if Is_Integer_Type (Index) then |
| Hi := |
| Make_Op_Add (Loc, |
| Left_Opnd => New_Copy_Tree (Lo), |
| Right_Opnd => Length_Expr); |
| else |
| Hi := |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Val, |
| Prefix => New_Occurrence_Of (Index, Loc), |
| Expressions => New_List ( |
| Make_Op_Add (Loc, |
| Left_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Pos, |
| Prefix => New_Occurrence_Of (Index, Loc), |
| Expressions => New_List (New_Copy_Tree (Lo))), |
| Right_Opnd => Length_Expr))); |
| end if; |
| |
| return |
| Make_Range (Loc, |
| Low_Bound => Lo, |
| High_Bound => Hi); |
| end Make_Literal_Range; |
| |
| -------------------------- |
| -- Make_Non_Empty_Check -- |
| -------------------------- |
| |
| function Make_Non_Empty_Check |
| (Loc : Source_Ptr; |
| N : Node_Id) return Node_Id |
| is |
| begin |
| return |
| Make_Op_Ne (Loc, |
| Left_Opnd => |
| Make_Attribute_Reference (Loc, |
| Attribute_Name => Name_Length, |
| Prefix => Duplicate_Subexpr_No_Checks (N, Name_Req => True)), |
| Right_Opnd => |
| Make_Integer_Literal (Loc, 0)); |
| end Make_Non_Empty_Check; |
| |
| ------------------------- |
| -- Make_Predicate_Call -- |
| ------------------------- |
| |
| function Make_Predicate_Call |
| (Typ : Entity_Id; |
| Expr : Node_Id) return Node_Id |
| is |
| Loc : constant Source_Ptr := Sloc (Expr); |
| |
| begin |
| pragma Assert (Present (Predicate_Function (Typ))); |
| |
| return |
| Make_Function_Call (Loc, |
| Name => |
| New_Occurrence_Of (Predicate_Function (Typ), Loc), |
| Parameter_Associations => New_List (Relocate_Node (Expr))); |
| end Make_Predicate_Call; |
| |
| -------------------------- |
| -- Make_Predicate_Check -- |
| -------------------------- |
| |
| function Make_Predicate_Check |
| (Typ : Entity_Id; |
| Expr : Node_Id) return Node_Id |
| is |
| Loc : constant Source_Ptr := Sloc (Expr); |
| |
| begin |
| return |
| Make_Pragma (Loc, |
| Pragma_Identifier => Make_Identifier (Loc, Name_Check), |
| Pragma_Argument_Associations => New_List ( |
| Make_Pragma_Argument_Association (Loc, |
| Expression => Make_Identifier (Loc, Name_Predicate)), |
| Make_Pragma_Argument_Association (Loc, |
| Expression => Make_Predicate_Call (Typ, Expr)))); |
| end Make_Predicate_Check; |
| |
| ---------------------------- |
| -- Make_Subtype_From_Expr -- |
| ---------------------------- |
| |
| -- 1. If Expr is an unconstrained array expression, creates |
| -- Unc_Type(Expr'first(1)..Expr'last(1),..., Expr'first(n)..Expr'last(n)) |
| |
| -- 2. If Expr is a unconstrained discriminated type expression, creates |
| -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n) |
| |
| -- 3. If Expr is class-wide, creates an implicit class wide subtype |
| |
| function Make_Subtype_From_Expr |
| (E : Node_Id; |
| Unc_Typ : Entity_Id) return Node_Id |
| is |
| Loc : constant Source_Ptr := Sloc (E); |
| List_Constr : constant List_Id := New_List; |
| D : Entity_Id; |
| |
| Full_Subtyp : Entity_Id; |
| Priv_Subtyp : Entity_Id; |
| Utyp : Entity_Id; |
| Full_Exp : Node_Id; |
| |
| begin |
| if Is_Private_Type (Unc_Typ) |
| and then Has_Unknown_Discriminants (Unc_Typ) |
| then |
| -- Prepare the subtype completion, Go to base type to |
| -- find underlying type, because the type may be a generic |
| -- actual or an explicit subtype. |
| |
| Utyp := Underlying_Type (Base_Type (Unc_Typ)); |
| Full_Subtyp := Make_Temporary (Loc, 'C'); |
| Full_Exp := |
| Unchecked_Convert_To (Utyp, Duplicate_Subexpr_No_Checks (E)); |
| Set_Parent (Full_Exp, Parent (E)); |
| |
| Priv_Subtyp := Make_Temporary (Loc, 'P'); |
| |
| Insert_Action (E, |
| Make_Subtype_Declaration (Loc, |
| Defining_Identifier => Full_Subtyp, |
| Subtype_Indication => Make_Subtype_From_Expr (Full_Exp, Utyp))); |
| |
| -- Define the dummy private subtype |
| |
| Set_Ekind (Priv_Subtyp, Subtype_Kind (Ekind (Unc_Typ))); |
| Set_Etype (Priv_Subtyp, Base_Type (Unc_Typ)); |
| Set_Scope (Priv_Subtyp, Full_Subtyp); |
| Set_Is_Constrained (Priv_Subtyp); |
| Set_Is_Tagged_Type (Priv_Subtyp, Is_Tagged_Type (Unc_Typ)); |
| Set_Is_Itype (Priv_Subtyp); |
| Set_Associated_Node_For_Itype (Priv_Subtyp, E); |
| |
| if Is_Tagged_Type (Priv_Subtyp) then |
| Set_Class_Wide_Type |
| (Base_Type (Priv_Subtyp), Class_Wide_Type (Unc_Typ)); |
| Set_Direct_Primitive_Operations (Priv_Subtyp, |
| Direct_Primitive_Operations (Unc_Typ)); |
| end if; |
| |
| Set_Full_View (Priv_Subtyp, Full_Subtyp); |
| |
| return New_Reference_To (Priv_Subtyp, Loc); |
| |
| elsif Is_Array_Type (Unc_Typ) then |
| for J in 1 .. Number_Dimensions (Unc_Typ) loop |
| Append_To (List_Constr, |
| Make_Range (Loc, |
| Low_Bound => |
| Make_Attribute_Reference (Loc, |
| Prefix => Duplicate_Subexpr_No_Checks (E), |
| Attribute_Name => Name_First, |
| Expressions => New_List ( |
| Make_Integer_Literal (Loc, J))), |
| |
| High_Bound => |
| Make_Attribute_Reference (Loc, |
| Prefix => Duplicate_Subexpr_No_Checks (E), |
| Attribute_Name => Name_Last, |
| Expressions => New_List ( |
| Make_Integer_Literal (Loc, J))))); |
| end loop; |
| |
| elsif Is_Class_Wide_Type (Unc_Typ) then |
| declare |
| CW_Subtype : Entity_Id; |
| EQ_Typ : Entity_Id := Empty; |
| |
| begin |
| -- A class-wide equivalent type is not needed when VM_Target |
| -- because the VM back-ends handle the class-wide object |
| -- initialization itself (and doesn't need or want the |
| -- additional intermediate type to handle the assignment). |
| |
| if Expander_Active and then Tagged_Type_Expansion then |
| |
| -- If this is the class_wide type of a completion that is a |
| -- record subtype, set the type of the class_wide type to be |
| -- the full base type, for use in the expanded code for the |
| -- equivalent type. Should this be done earlier when the |
| -- completion is analyzed ??? |
| |
| if Is_Private_Type (Etype (Unc_Typ)) |
| and then |
| Ekind (Full_View (Etype (Unc_Typ))) = E_Record_Subtype |
| then |
| Set_Etype (Unc_Typ, Base_Type (Full_View (Etype (Unc_Typ)))); |
| end if; |
| |
| EQ_Typ := Make_CW_Equivalent_Type (Unc_Typ, E); |
| end if; |
| |
| CW_Subtype := New_Class_Wide_Subtype (Unc_Typ, E); |
| Set_Equivalent_Type (CW_Subtype, EQ_Typ); |
| Set_Cloned_Subtype (CW_Subtype, Base_Type (Unc_Typ)); |
| |
| return New_Occurrence_Of (CW_Subtype, Loc); |
| end; |
| |
| -- Indefinite record type with discriminants |
| |
| else |
| D := First_Discriminant (Unc_Typ); |
| while Present (D) loop |
| Append_To (List_Constr, |
| Make_Selected_Component (Loc, |
| Prefix => Duplicate_Subexpr_No_Checks (E), |
| Selector_Name => New_Reference_To (D, Loc))); |
| |
| Next_Discriminant (D); |
| end loop; |
| end if; |
| |
| return |
| Make_Subtype_Indication (Loc, |
| Subtype_Mark => New_Reference_To (Unc_Typ, Loc), |
| Constraint => |
| Make_Index_Or_Discriminant_Constraint (Loc, |
| Constraints => List_Constr)); |
| end Make_Subtype_From_Expr; |
| |
| ----------------------------- |
| -- May_Generate_Large_Temp -- |
| ----------------------------- |
| |
| -- At the current time, the only types that we return False for (i.e. where |
| -- we decide we know they cannot generate large temps) are ones where we |
| -- know the size is 256 bits or less at compile time, and we are still not |
| -- doing a thorough job on arrays and records ??? |
| |
| function May_Generate_Large_Temp (Typ : Entity_Id) return Boolean is |
| begin |
| if not Size_Known_At_Compile_Time (Typ) then |
| return False; |
| |
| elsif Esize (Typ) /= 0 and then Esize (Typ) <= 256 then |
| return False; |
| |
| elsif Is_Array_Type (Typ) and then Present (Packed_Array_Type (Typ)) then |
| return May_Generate_Large_Temp (Packed_Array_Type (Typ)); |
| |
| -- We could do more here to find other small types ??? |
| |
| else |
| return True; |
| end if; |
| end May_Generate_Large_Temp; |
| |
| ------------------------ |
| -- Needs_Finalization -- |
| ------------------------ |
| |
| function Needs_Finalization (T : Entity_Id) return Boolean is |
| function Has_Some_Controlled_Component (Rec : Entity_Id) return Boolean; |
| -- If type is not frozen yet, check explicitly among its components, |
| -- because the Has_Controlled_Component flag is not necessarily set. |
| |
| ----------------------------------- |
| -- Has_Some_Controlled_Component -- |
| ----------------------------------- |
| |
| function Has_Some_Controlled_Component |
| (Rec : Entity_Id) return Boolean |
| is |
| Comp : Entity_Id; |
| |
| begin |
| if Has_Controlled_Component (Rec) then |
| return True; |
| |
| elsif not Is_Frozen (Rec) then |
| if Is_Record_Type (Rec) then |
| Comp := First_Entity (Rec); |
| |
| while Present (Comp) loop |
| if not Is_Type (Comp) |
| and then Needs_Finalization (Etype (Comp)) |
| then |
| return True; |
| end if; |
| |
| Next_Entity (Comp); |
| end loop; |
| |
| return False; |
| |
| elsif Is_Array_Type (Rec) then |
| return Needs_Finalization (Component_Type (Rec)); |
| |
| else |
| return Has_Controlled_Component (Rec); |
| end if; |
| else |
| return False; |
| end if; |
| end Has_Some_Controlled_Component; |
| |
| -- Start of processing for Needs_Finalization |
| |
| begin |
| -- Certain run-time configurations and targets do not provide support |
| -- for controlled types. |
| |
| if Restriction_Active (No_Finalization) then |
| return False; |
| |
| -- C, C++, CIL and Java types are not considered controlled. It is |
| -- assumed that the non-Ada side will handle their clean up. |
| |
| elsif Convention (T) = Convention_C |
| or else Convention (T) = Convention_CIL |
| or else Convention (T) = Convention_CPP |
| or else Convention (T) = Convention_Java |
| then |
| return False; |
| |
| else |
| -- Class-wide types are treated as controlled because derivations |
| -- from the root type can introduce controlled components. |
| |
| return |
| Is_Class_Wide_Type (T) |
| or else Is_Controlled (T) |
| or else Has_Controlled_Component (T) |
| or else Has_Some_Controlled_Component (T) |
| or else |
| (Is_Concurrent_Type (T) |
| and then Present (Corresponding_Record_Type (T)) |
| and then Needs_Finalization (Corresponding_Record_Type (T))); |
| end if; |
| end Needs_Finalization; |
| |
| ---------------------------- |
| -- Needs_Constant_Address -- |
| ---------------------------- |
| |
| function Needs_Constant_Address |
| (Decl : Node_Id; |
| Typ : Entity_Id) return Boolean |
| is |
| begin |
| |
| -- If we have no initialization of any kind, then we don't need to place |
| -- any restrictions on the address clause, because the object will be |
| -- elaborated after the address clause is evaluated. This happens if the |
| -- declaration has no initial expression, or the type has no implicit |
| -- initialization, or the object is imported. |
| |
| -- The same holds for all initialized scalar types and all access types. |
| -- Packed bit arrays of size up to 64 are represented using a modular |
| -- type with an initialization (to zero) and can be processed like other |
| -- initialized scalar types. |
| |
| -- If the type is controlled, code to attach the object to a |
| -- finalization chain is generated at the point of declaration, and |
| -- therefore the elaboration of the object cannot be delayed: the |
| -- address expression must be a constant. |
| |
| if No (Expression (Decl)) |
| and then not Needs_Finalization (Typ) |
| and then |
| (not Has_Non_Null_Base_Init_Proc (Typ) |
| or else Is_Imported (Defining_Identifier (Decl))) |
| then |
| return False; |
| |
| elsif (Present (Expression (Decl)) and then Is_Scalar_Type (Typ)) |
| or else Is_Access_Type (Typ) |
| or else |
| (Is_Bit_Packed_Array (Typ) |
| and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))) |
| then |
| return False; |
| |
| else |
| |
| -- Otherwise, we require the address clause to be constant because |
| -- the call to the initialization procedure (or the attach code) has |
| -- to happen at the point of the declaration. |
| |
| -- Actually the IP call has been moved to the freeze actions anyway, |
| -- so maybe we can relax this restriction??? |
| |
| return True; |
| end if; |
| end Needs_Constant_Address; |
| |
| ---------------------------- |
| -- New_Class_Wide_Subtype -- |
| ---------------------------- |
| |
| function New_Class_Wide_Subtype |
| (CW_Typ : Entity_Id; |
| N : Node_Id) return Entity_Id |
| is |
| Res : constant Entity_Id := Create_Itype (E_Void, N); |
| Res_Name : constant Name_Id := Chars (Res); |
| Res_Scope : constant Entity_Id := Scope (Res); |
| |
| begin |
| Copy_Node (CW_Typ, Res); |
| Set_Comes_From_Source (Res, False); |
| Set_Sloc (Res, Sloc (N)); |
| Set_Is_Itype (Res); |
| Set_Associated_Node_For_Itype (Res, N); |
| Set_Is_Public (Res, False); -- By default, may be changed below. |
| Set_Public_Status (Res); |
| Set_Chars (Res, Res_Name); |
| Set_Scope (Res, Res_Scope); |
| Set_Ekind (Res, E_Class_Wide_Subtype); |
| Set_Next_Entity (Res, Empty); |
| Set_Etype (Res, Base_Type (CW_Typ)); |
| Set_Is_Frozen (Res, False); |
| Set_Freeze_Node (Res, Empty); |
| return (Res); |
| end New_Class_Wide_Subtype; |
| |
| -------------------------------- |
| -- Non_Limited_Designated_Type -- |
| --------------------------------- |
| |
| function Non_Limited_Designated_Type (T : Entity_Id) return Entity_Id is |
| Desig : constant Entity_Id := Designated_Type (T); |
| begin |
| if Ekind (Desig) = E_Incomplete_Type |
| and then Present (Non_Limited_View (Desig)) |
| then |
| return Non_Limited_View (Desig); |
| else |
| return Desig; |
| end if; |
| end Non_Limited_Designated_Type; |
| |
| ----------------------------------- |
| -- OK_To_Do_Constant_Replacement -- |
| ----------------------------------- |
| |
| function OK_To_Do_Constant_Replacement (E : Entity_Id) return Boolean is |
| ES : constant Entity_Id := Scope (E); |
| CS : Entity_Id; |
| |
| begin |
| -- Do not replace statically allocated objects, because they may be |
| -- modified outside the current scope. |
| |
| if Is_Statically_Allocated (E) then |
| return False; |
| |
| -- Do not replace aliased or volatile objects, since we don't know what |
| -- else might change the value. |
| |
| elsif Is_Aliased (E) or else Treat_As_Volatile (E) then |
| return False; |
| |
| -- Debug flag -gnatdM disconnects this optimization |
| |
| elsif Debug_Flag_MM then |
| return False; |
| |
| -- Otherwise check scopes |
| |
| else |
| CS := Current_Scope; |
| |
| loop |
| -- If we are in right scope, replacement is safe |
| |
| if CS = ES then |
| return True; |
| |
| -- Packages do not affect the determination of safety |
| |
| elsif Ekind (CS) = E_Package then |
| exit when CS = Standard_Standard; |
| CS := Scope (CS); |
| |
| -- Blocks do not affect the determination of safety |
| |
| elsif Ekind (CS) = E_Block then |
| CS := Scope (CS); |
| |
| -- Loops do not affect the determination of safety. Note that we |
| -- kill all current values on entry to a loop, so we are just |
| -- talking about processing within a loop here. |
| |
| elsif Ekind (CS) = E_Loop then |
| CS := Scope (CS); |
| |
| -- Otherwise, the reference is dubious, and we cannot be sure that |
| -- it is safe to do the replacement. |
| |
| else |
| exit; |
| end if; |
| end loop; |
| |
| return False; |
| end if; |
| end OK_To_Do_Constant_Replacement; |
| |
| ------------------------------------ |
| -- Possible_Bit_Aligned_Component -- |
| ------------------------------------ |
| |
| function Possible_Bit_Aligned_Component (N : Node_Id) return Boolean is |
| begin |
| case Nkind (N) is |
| |
| -- Case of indexed component |
| |
| when N_Indexed_Component => |
| declare |
| P : constant Node_Id := Prefix (N); |
| Ptyp : constant Entity_Id := Etype (P); |
| |
| begin |
| -- If we know the component size and it is less than 64, then |
| -- we are definitely OK. The back end always does assignment of |
| -- misaligned small objects correctly. |
| |
| if Known_Static_Component_Size (Ptyp) |
| and then Component_Size (Ptyp) <= 64 |
| then |
| return False; |
| |
| -- Otherwise, we need to test the prefix, to see if we are |
| -- indexing from a possibly unaligned component. |
| |
| else |
| return Possible_Bit_Aligned_Component (P); |
| end if; |
| end; |
| |
| -- Case of selected component |
| |
| when N_Selected_Component => |
| declare |
| P : constant Node_Id := Prefix (N); |
| Comp : constant Entity_Id := Entity (Selector_Name (N)); |
| |
| begin |
| -- If there is no component clause, then we are in the clear |
| -- since the back end will never misalign a large component |
| -- unless it is forced to do so. In the clear means we need |
| -- only the recursive test on the prefix. |
| |
| if Component_May_Be_Bit_Aligned (Comp) then |
| return True; |
| else |
| return Possible_Bit_Aligned_Component (P); |
| end if; |
| end; |
| |
| -- For a slice, test the prefix, if that is possibly misaligned, |
| -- then for sure the slice is! |
| |
| when N_Slice => |
| return Possible_Bit_Aligned_Component (Prefix (N)); |
| |
| -- For an unchecked conversion, check whether the expression may |
| -- be bit-aligned. |
| |
| when N_Unchecked_Type_Conversion => |
| return Possible_Bit_Aligned_Component (Expression (N)); |
| |
| -- If we have none of the above, it means that we have fallen off the |
| -- top testing prefixes recursively, and we now have a stand alone |
| -- object, where we don't have a problem. |
| |
| when others => |
| return False; |
| |
| end case; |
| end Possible_Bit_Aligned_Component; |
| |
| ----------------------------------------------- |
| -- Process_Statements_For_Controlled_Objects -- |
| ----------------------------------------------- |
| |
| procedure Process_Statements_For_Controlled_Objects (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| |
| function Are_Wrapped (L : List_Id) return Boolean; |
| -- Determine whether list L contains only one statement which is a block |
| |
| function Wrap_Statements_In_Block (L : List_Id) return Node_Id; |
| -- Given a list of statements L, wrap it in a block statement and return |
| -- the generated node. |
| |
| ----------------- |
| -- Are_Wrapped -- |
| ----------------- |
| |
| function Are_Wrapped (L : List_Id) return Boolean is |
| Stmt : constant Node_Id := First (L); |
| begin |
| return |
| Present (Stmt) |
| and then No (Next (Stmt)) |
| and then Nkind (Stmt) = N_Block_Statement; |
| end Are_Wrapped; |
| |
| ------------------------------ |
| -- Wrap_Statements_In_Block -- |
| ------------------------------ |
| |
| function Wrap_Statements_In_Block (L : List_Id) return Node_Id is |
| begin |
| return |
| Make_Block_Statement (Loc, |
| Declarations => No_List, |
| Handled_Statement_Sequence => |
| Make_Handled_Sequence_Of_Statements (Loc, |
| Statements => L)); |
| end Wrap_Statements_In_Block; |
| |
| -- Local variables |
| |
| Block : Node_Id; |
| |
| -- Start of processing for Process_Statements_For_Controlled_Objects |
| |
| begin |
| -- Whenever a non-handled statement list is wrapped in a block, the |
| -- block must be explicitly analyzed to redecorate all entities in the |
| -- list and ensure that a finalizer is properly built. |
| |
| case Nkind (N) is |
| when N_Elsif_Part | |
| N_If_Statement | |
| N_Conditional_Entry_Call | |
| N_Selective_Accept => |
| |
| -- Check the "then statements" for elsif parts and if statements |
| |
| if Nkind_In (N, N_Elsif_Part, N_If_Statement) |
| and then not Is_Empty_List (Then_Statements (N)) |
| and then not Are_Wrapped (Then_Statements (N)) |
| and then Requires_Cleanup_Actions |
| (Then_Statements (N), False, False) |
| then |
| Block := Wrap_Statements_In_Block (Then_Statements (N)); |
| Set_Then_Statements (N, New_List (Block)); |
| |
| Analyze (Block); |
| end if; |
| |
| -- Check the "else statements" for conditional entry calls, if |
| -- statements and selective accepts. |
| |
| if Nkind_In (N, N_Conditional_Entry_Call, |
| N_If_Statement, |
| N_Selective_Accept) |
| and then not Is_Empty_List (Else_Statements (N)) |
| and then not Are_Wrapped (Else_Statements (N)) |
| and then Requires_Cleanup_Actions |
| (Else_Statements (N), False, False) |
| then |
| Block := Wrap_Statements_In_Block (Else_Statements (N)); |
| Set_Else_Statements (N, New_List (Block)); |
| |
| Analyze (Block); |
| end if; |
| |
| when N_Abortable_Part | |
| N_Accept_Alternative | |
| N_Case_Statement_Alternative | |
| N_Delay_Alternative | |
| N_Entry_Call_Alternative | |
| N_Exception_Handler | |
| N_Loop_Statement | |
| N_Triggering_Alternative => |
| |
| if not Is_Empty_List (Statements (N)) |
| and then not Are_Wrapped (Statements (N)) |
| and then Requires_Cleanup_Actions (Statements (N), False, False) |
| then |
| Block := Wrap_Statements_In_Block (Statements (N)); |
| Set_Statements (N, New_List (Block)); |
| |
| Analyze (Block); |
| end if; |
| |
| when others => |
| null; |
| end case; |
| end Process_Statements_For_Controlled_Objects; |
| |
| ---------------------- |
| -- Remove_Init_Call -- |
| ---------------------- |
| |
| function Remove_Init_Call |
| (Var : Entity_Id; |
| Rep_Clause : Node_Id) return Node_Id |
| is |
| Par : constant Node_Id := Parent (Var); |
| Typ : constant Entity_Id := Etype (Var); |
| |
| Init_Proc : Entity_Id; |
| -- Initialization procedure for Typ |
| |
| function Find_Init_Call_In_List (From : Node_Id) return Node_Id; |
| -- Look for init call for Var starting at From and scanning the |
| -- enclosing list until Rep_Clause or the end of the list is reached. |
| |
| ---------------------------- |
| -- Find_Init_Call_In_List -- |
| ---------------------------- |
| |
| function Find_Init_Call_In_List (From : Node_Id) return Node_Id is |
| Init_Call : Node_Id; |
| |
| begin |
| Init_Call := From; |
| while Present (Init_Call) and then Init_Call /= Rep_Clause loop |
| if Nkind (Init_Call) = N_Procedure_Call_Statement |
| and then Is_Entity_Name (Name (Init_Call)) |
| and then Entity (Name (Init_Call)) = Init_Proc |
| then |
| return Init_Call; |
| end if; |
| |
| Next (Init_Call); |
| end loop; |
| |
| return Empty; |
| end Find_Init_Call_In_List; |
| |
| Init_Call : Node_Id; |
| |
| -- Start of processing for Find_Init_Call |
| |
| begin |
| if Present (Initialization_Statements (Var)) then |
| Init_Call := Initialization_Statements (Var); |
| Set_Initialization_Statements (Var, Empty); |
| |
| elsif not Has_Non_Null_Base_Init_Proc (Typ) then |
| |
| -- No init proc for the type, so obviously no call to be found |
| |
| return Empty; |
| |
| else |
| -- We might be able to handle other cases below by just properly |
| -- setting Initialization_Statements at the point where the init proc |
| -- call is generated??? |
| |
| Init_Proc := Base_Init_Proc (Typ); |
| |
| -- First scan the list containing the declaration of Var |
| |
| Init_Call := Find_Init_Call_In_List (From => Next (Par)); |
| |
| -- If not found, also look on Var's freeze actions list, if any, |
| -- since the init call may have been moved there (case of an address |
| -- clause applying to Var). |
| |
| if No (Init_Call) and then Present (Freeze_Node (Var)) then |
| Init_Call := |
| Find_Init_Call_In_List (First (Actions (Freeze_Node (Var)))); |
| end if; |
| |
| -- If the initialization call has actuals that use the secondary |
| -- stack, the call may have been wrapped into a temporary block, in |
| -- which case the block itself has to be removed. |
| |
| if No (Init_Call) and then Nkind (Next (Par)) = N_Block_Statement then |
| declare |
| Blk : constant Node_Id := Next (Par); |
| begin |
| if Present |
| (Find_Init_Call_In_List |
| (First (Statements (Handled_Statement_Sequence (Blk))))) |
| then |
| Init_Call := Blk; |
| end if; |
| end; |
| end if; |
| end if; |
| |
| if Present (Init_Call) then |
| Remove (Init_Call); |
| end if; |
| return Init_Call; |
| end Remove_Init_Call; |
| |
| ------------------------- |
| -- Remove_Side_Effects -- |
| ------------------------- |
| |
| procedure Remove_Side_Effects |
| (Exp : Node_Id; |
| Name_Req : Boolean := False; |
| Variable_Ref : Boolean := False) |
| is |
| Loc : constant Source_Ptr := Sloc (Exp); |
| Exp_Type : constant Entity_Id := Etype (Exp); |
| Svg_Suppress : constant Suppress_Record := Scope_Suppress; |
| Def_Id : Entity_Id; |
| E : Node_Id; |
| New_Exp : Node_Id; |
| Ptr_Typ_Decl : Node_Id; |
| Ref_Type : Entity_Id; |
| Res : Node_Id; |
| |
| function Side_Effect_Free (N : Node_Id) return Boolean; |
| -- Determines if the tree N represents an expression that is known not |
| -- to have side effects, and for which no processing is required. |
| |
| function Side_Effect_Free (L : List_Id) return Boolean; |
| -- Determines if all elements of the list L are side effect free |
| |
| function Safe_Prefixed_Reference (N : Node_Id) return Boolean; |
| -- The argument N is a construct where the Prefix is dereferenced if it |
| -- is an access type and the result is a variable. The call returns True |
| -- if the construct is side effect free (not considering side effects in |
| -- other than the prefix which are to be tested by the caller). |
| |
| function Within_In_Parameter (N : Node_Id) return Boolean; |
| -- Determines if N is a subcomponent of a composite in-parameter. If so, |
| -- N is not side-effect free when the actual is global and modifiable |
| -- indirectly from within a subprogram, because it may be passed by |
| -- reference. The front-end must be conservative here and assume that |
| -- this may happen with any array or record type. On the other hand, we |
| -- cannot create temporaries for all expressions for which this |
| -- condition is true, for various reasons that might require clearing up |
| -- ??? For example, discriminant references that appear out of place, or |
| -- spurious type errors with class-wide expressions. As a result, we |
| -- limit the transformation to loop bounds, which is so far the only |
| -- case that requires it. |
| |
| ----------------------------- |
| -- Safe_Prefixed_Reference -- |
| ----------------------------- |
| |
| function Safe_Prefixed_Reference (N : Node_Id) return Boolean is |
| begin |
| -- If prefix is not side effect free, definitely not safe |
| |
| if not Side_Effect_Free (Prefix (N)) then |
| return False; |
| |
| -- If the prefix is of an access type that is not access-to-constant, |
| -- then this construct is a variable reference, which means it is to |
| -- be considered to have side effects if Variable_Ref is set True. |
| |
| elsif Is_Access_Type (Etype (Prefix (N))) |
| and then not Is_Access_Constant (Etype (Prefix (N))) |
| and then Variable_Ref |
| then |
| -- Exception is a prefix that is the result of a previous removal |
| -- of side-effects. |
| |
| return Is_Entity_Name (Prefix (N)) |
| and then not Comes_From_Source (Prefix (N)) |
| and then Ekind (Entity (Prefix (N))) = E_Constant |
| and then Is_Internal_Name (Chars (Entity (Prefix (N)))); |
| |
| -- If the prefix is an explicit dereference then this construct is a |
| -- variable reference, which means it is to be considered to have |
| -- side effects if Variable_Ref is True. |
| |
| -- We do NOT exclude dereferences of access-to-constant types because |
| -- we handle them as constant view of variables. |
| |
| elsif Nkind (Prefix (N)) = N_Explicit_Dereference |
| and then Variable_Ref |
| then |
| return False; |
| |
| -- Note: The following test is the simplest way of solving a complex |
| -- problem uncovered by the following test (Side effect on loop bound |
| -- that is a subcomponent of a global variable: |
| |
| -- with Text_Io; use Text_Io; |
| -- procedure Tloop is |
| -- type X is |
| -- record |
| -- V : Natural := 4; |
| -- S : String (1..5) := (others => 'a'); |
| -- end record; |
| -- X1 : X; |
| |
| -- procedure Modi; |
| |
| -- generic |
| -- with procedure Action; |
| -- procedure Loop_G (Arg : X; Msg : String) |
| |
| -- procedure Loop_G (Arg : X; Msg : String) is |
| -- begin |
| -- Put_Line ("begin loop_g " & Msg & " will loop till: " |
| -- & Natural'Image (Arg.V)); |
| -- for Index in 1 .. Arg.V loop |
| -- Text_Io.Put_Line |
| -- (Natural'Image (Index) & " " & Arg.S (Index)); |
| -- if Index > 2 then |
| -- Modi; |
| -- end if; |
| -- end loop; |
| -- Put_Line ("end loop_g " & Msg); |
| -- end; |
| |
| -- procedure Loop1 is new Loop_G (Modi); |
| -- procedure Modi is |
| -- begin |
| -- X1.V := 1; |
| -- Loop1 (X1, "from modi"); |
| -- end; |
| -- |
| -- begin |
| -- Loop1 (X1, "initial"); |
| -- end; |
| |
| -- The output of the above program should be: |
| |
| -- begin loop_g initial will loop till: 4 |
| -- 1 a |
| -- 2 a |
| -- 3 a |
| -- begin loop_g from modi will loop till: 1 |
| -- 1 a |
| -- end loop_g from modi |
| -- 4 a |
| -- begin loop_g from modi will loop till: 1 |
| -- 1 a |
| -- end loop_g from modi |
| -- end loop_g initial |
| |
| -- If a loop bound is a subcomponent of a global variable, a |
| -- modification of that variable within the loop may incorrectly |
| -- affect the execution of the loop. |
| |
| elsif Nkind (Parent (Parent (N))) = N_Loop_Parameter_Specification |
| and then Within_In_Parameter (Prefix (N)) |
| and then Variable_Ref |
| then |
| return False; |
| |
| -- All other cases are side effect free |
| |
| else |
| return True; |
| end if; |
| end Safe_Prefixed_Reference; |
| |
| ---------------------- |
| -- Side_Effect_Free -- |
| ---------------------- |
| |
| function Side_Effect_Free (N : Node_Id) return Boolean is |
| begin |
| -- Note on checks that could raise Constraint_Error. Strictly, if we |
| -- take advantage of 11.6, these checks do not count as side effects. |
| -- However, we would prefer to consider that they are side effects, |
| -- since the backend CSE does not work very well on expressions which |
| -- can raise Constraint_Error. On the other hand if we don't consider |
| -- them to be side effect free, then we get some awkward expansions |
| -- in -gnato mode, resulting in code insertions at a point where we |
| -- do not have a clear model for performing the insertions. |
| |
| -- Special handling for entity names |
| |
| if Is_Entity_Name (N) then |
| |
| -- Variables are considered to be a side effect if Variable_Ref |
| -- is set or if we have a volatile reference and Name_Req is off. |
| -- If Name_Req is True then we can't help returning a name which |
| -- effectively allows multiple references in any case. |
| |
| if Is_Variable (N, Use_Original_Node => False) then |
| return not Variable_Ref |
| and then (not Is_Volatile_Reference (N) or else Name_Req); |
| |
| -- Any other entity (e.g. a subtype name) is definitely side |
| -- effect free. |
| |
| else |
| return True; |
| end if; |
| |
| -- A value known at compile time is always side effect free |
| |
| elsif Compile_Time_Known_Value (N) then |
| return True; |
| |
| -- A variable renaming is not side-effect free, because the renaming |
| -- will function like a macro in the front-end in some cases, and an |
| -- assignment can modify the component designated by N, so we need to |
| -- create a temporary for it. |
| |
| -- The guard testing for Entity being present is needed at least in |
| -- the case of rewritten predicate expressions, and may well also be |
| -- appropriate elsewhere. Obviously we can't go testing the entity |
| -- field if it does not exist, so it's reasonable to say that this is |
| -- not the renaming case if it does not exist. |
| |
| elsif Is_Entity_Name (Original_Node (N)) |
| and then Present (Entity (Original_Node (N))) |
| and then Is_Renaming_Of_Object (Entity (Original_Node (N))) |
| and then Ekind (Entity (Original_Node (N))) /= E_Constant |
| then |
| declare |
| RO : constant Node_Id := |
| Renamed_Object (Entity (Original_Node (N))); |
| |
| begin |
| -- If the renamed object is an indexed component, or an |
| -- explicit dereference, then the designated object could |
| -- be modified by an assignment. |
| |
| if Nkind_In (RO, N_Indexed_Component, |
| N_Explicit_Dereference) |
| then |
| return False; |
| |
| -- A selected component must have a safe prefix |
| |
| elsif Nkind (RO) = N_Selected_Component then |
| return Safe_Prefixed_Reference (RO); |
| |
| -- In all other cases, designated object cannot be changed so |
| -- we are side effect free. |
| |
| else |
| return True; |
| end if; |
| end; |
| |
| -- Remove_Side_Effects generates an object renaming declaration to |
| -- capture the expression of a class-wide expression. In VM targets |
| -- the frontend performs no expansion for dispatching calls to |
| -- class- wide types since they are handled by the VM. Hence, we must |
| -- locate here if this node corresponds to a previous invocation of |
| -- Remove_Side_Effects to avoid a never ending loop in the frontend. |
| |
| elsif VM_Target /= No_VM |
| and then not Comes_From_Source (N) |
| and then Nkind (Parent (N)) = N_Object_Renaming_Declaration |
| and then Is_Class_Wide_Type (Etype (N)) |
| then |
| return True; |
| end if; |
| |
| -- For other than entity names and compile time known values, |
| -- check the node kind for special processing. |
| |
| case Nkind (N) is |
| |
| -- An attribute reference is side effect free if its expressions |
| -- are side effect free and its prefix is side effect free or |
| -- is an entity reference. |
| |
| -- Is this right? what about x'first where x is a variable??? |
| |
| when N_Attribute_Reference => |
| return Side_Effect_Free (Expressions (N)) |
| and then Attribute_Name (N) /= Name_Input |
| and then (Is_Entity_Name (Prefix (N)) |
| or else Side_Effect_Free (Prefix (N))); |
| |
| -- A binary operator is side effect free if and both operands are |
| -- side effect free. For this purpose binary operators include |
| -- membership tests and short circuit forms. |
| |
| when N_Binary_Op | N_Membership_Test | N_Short_Circuit => |
| return Side_Effect_Free (Left_Opnd (N)) |
| and then |
| Side_Effect_Free (Right_Opnd (N)); |
| |
| -- An explicit dereference is side effect free only if it is |
| -- a side effect free prefixed reference. |
| |
| when N_Explicit_Dereference => |
| return Safe_Prefixed_Reference (N); |
| |
| -- A call to _rep_to_pos is side effect free, since we generate |
| -- this pure function call ourselves. Moreover it is critically |
| -- important to make this exception, since otherwise we can have |
| -- discriminants in array components which don't look side effect |
| -- free in the case of an array whose index type is an enumeration |
| -- type with an enumeration rep clause. |
| |
| -- All other function calls are not side effect free |
| |
| when N_Function_Call => |
| return Nkind (Name (N)) = N_Identifier |
| and then Is_TSS (Name (N), TSS_Rep_To_Pos) |
| and then |
| Side_Effect_Free (First (Parameter_Associations (N))); |
| |
| -- An indexed component is side effect free if it is a side |
| -- effect free prefixed reference and all the indexing |
| -- expressions are side effect free. |
| |
| when N_Indexed_Component => |
| return Side_Effect_Free (Expressions (N)) |
| and then Safe_Prefixed_Reference (N); |
| |
| -- A type qualification is side effect free if the expression |
| -- is side effect free. |
| |
| when N_Qualified_Expression => |
| return Side_Effect_Free (Expression (N)); |
| |
| -- A selected component is side effect free only if it is a side |
| -- effect free prefixed reference. If it designates a component |
| -- with a rep. clause it must be treated has having a potential |
| -- side effect, because it may be modified through a renaming, and |
| -- a subsequent use of the renaming as a macro will yield the |
| -- wrong value. This complex interaction between renaming and |
| -- removing side effects is a reminder that the latter has become |
| -- a headache to maintain, and that it should be removed in favor |
| -- of the gcc mechanism to capture values ??? |
| |
| when N_Selected_Component => |
| if Nkind (Parent (N)) = N_Explicit_Dereference |
| and then Has_Non_Standard_Rep (Designated_Type (Etype (N))) |
| then |
| return False; |
| else |
| return Safe_Prefixed_Reference (N); |
| end if; |
| |
| -- A range is side effect free if the bounds are side effect free |
| |
| when N_Range => |
| return Side_Effect_Free (Low_Bound (N)) |
| and then Side_Effect_Free (High_Bound (N)); |
| |
| -- A slice is side effect free if it is a side effect free |
| -- prefixed reference and the bounds are side effect free. |
| |
| when N_Slice => |
| return Side_Effect_Free (Discrete_Range (N)) |
| and then Safe_Prefixed_Reference (N); |
| |
| -- A type conversion is side effect free if the expression to be |
| -- converted is side effect free. |
| |
| when N_Type_Conversion => |
| return Side_Effect_Free (Expression (N)); |
| |
| -- A unary operator is side effect free if the operand |
| -- is side effect free. |
| |
| when N_Unary_Op => |
| return Side_Effect_Free (Right_Opnd (N)); |
| |
| -- An unchecked type conversion is side effect free only if it |
| -- is safe and its argument is side effect free. |
| |
| when N_Unchecked_Type_Conversion => |
| return Safe_Unchecked_Type_Conversion (N) |
| and then Side_Effect_Free (Expression (N)); |
| |
| -- An unchecked expression is side effect free if its expression |
| -- is side effect free. |
| |
| when N_Unchecked_Expression => |
| return Side_Effect_Free (Expression (N)); |
| |
| -- A literal is side effect free |
| |
| when N_Character_Literal | |
| N_Integer_Literal | |
| N_Real_Literal | |
| N_String_Literal => |
| return True; |
| |
| -- We consider that anything else has side effects. This is a bit |
| -- crude, but we are pretty close for most common cases, and we |
| -- are certainly correct (i.e. we never return True when the |
| -- answer should be False). |
| |
| when others => |
| return False; |
| end case; |
| end Side_Effect_Free; |
| |
| -- A list is side effect free if all elements of the list are side |
| -- effect free. |
| |
| function Side_Effect_Free (L : List_Id) return Boolean is |
| N : Node_Id; |
| |
| begin |
| if L = No_List or else L = Error_List then |
| return True; |
| |
| else |
| N := First (L); |
| while Present (N) loop |
| if not Side_Effect_Free (N) then |
| return False; |
| else |
| Next (N); |
| end if; |
| end loop; |
| |
| return True; |
| end if; |
| end Side_Effect_Free; |
| |
| ------------------------- |
| -- Within_In_Parameter -- |
| ------------------------- |
| |
| function Within_In_Parameter (N : Node_Id) return Boolean is |
| begin |
| if not Comes_From_Source (N) then |
| return False; |
| |
| elsif Is_Entity_Name (N) then |
| return Ekind (Entity (N)) = E_In_Parameter; |
| |
| elsif Nkind_In (N, N_Indexed_Component, N_Selected_Component) then |
| return Within_In_Parameter (Prefix (N)); |
| |
| else |
| return False; |
| end if; |
| end Within_In_Parameter; |
| |
| -- Start of processing for Remove_Side_Effects |
| |
| begin |
| -- Handle cases in which there is nothing to do |
| |
| if not Expander_Active then |
| return; |
| end if; |
| |
| -- Cannot generate temporaries if the invocation to remove side effects |
| -- was issued too early and the type of the expression is not resolved |
| -- (this happens because routines Duplicate_Subexpr_XX implicitly invoke |
| -- Remove_Side_Effects). |
| |
| if No (Exp_Type) |
| or else Ekind (Exp_Type) = E_Access_Attribute_Type |
| then |
| return; |
| |
| -- No action needed for side-effect free expressions |
| |
| elsif Side_Effect_Free (Exp) then |
| return; |
| end if; |
| |
| -- The remaining procesaing is done with all checks suppressed |
| |
| -- Note: from now on, don't use return statements, instead do a goto |
| -- Leave, to ensure that we properly restore Scope_Suppress.Suppress. |
| |
| Scope_Suppress.Suppress := (others => True); |
| |
| -- If it is a scalar type and we need to capture the value, just make |
| -- a copy. Likewise for a function call, an attribute reference, an |
| -- allocator, or an operator. And if we have a volatile reference and |
| -- Name_Req is not set (see comments above for Side_Effect_Free). |
| |
| if Is_Elementary_Type (Exp_Type) |
| and then (Variable_Ref |
| or else Nkind_In (Exp, N_Function_Call, |
| N_Attribute_Reference, |
| N_Allocator) |
| or else Nkind (Exp) in N_Op |
| or else (not Name_Req and then Is_Volatile_Reference (Exp))) |
| then |
| Def_Id := Make_Temporary (Loc, 'R', Exp); |
| Set_Etype (Def_Id, Exp_Type); |
| Res := New_Reference_To (Def_Id, Loc); |
| |
| -- If the expression is a packed reference, it must be reanalyzed and |
| -- expanded, depending on context. This is the case for actuals where |
| -- a constraint check may capture the actual before expansion of the |
| -- call is complete. |
| |
| if Nkind (Exp) = N_Indexed_Component |
| and then Is_Packed (Etype (Prefix (Exp))) |
| then |
| Set_Analyzed (Exp, False); |
| Set_Analyzed (Prefix (Exp), False); |
| end if; |
| |
| E := |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Object_Definition => New_Reference_To (Exp_Type, Loc), |
| Constant_Present => True, |
| Expression => Relocate_Node (Exp)); |
| |
| Set_Assignment_OK (E); |
| Insert_Action (Exp, E); |
| |
| -- If the expression has the form v.all then we can just capture the |
| -- pointer, and then do an explicit dereference on the result. |
| |
| elsif Nkind (Exp) = N_Explicit_Dereference then |
| Def_Id := Make_Temporary (Loc, 'R', Exp); |
| Res := |
| Make_Explicit_Dereference (Loc, New_Reference_To (Def_Id, Loc)); |
| |
| Insert_Action (Exp, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Object_Definition => |
| New_Reference_To (Etype (Prefix (Exp)), Loc), |
| Constant_Present => True, |
| Expression => Relocate_Node (Prefix (Exp)))); |
| |
| -- Similar processing for an unchecked conversion of an expression of |
| -- the form v.all, where we want the same kind of treatment. |
| |
| elsif Nkind (Exp) = N_Unchecked_Type_Conversion |
| and then Nkind (Expression (Exp)) = N_Explicit_Dereference |
| then |
| Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref); |
| goto Leave; |
| |
| -- If this is a type conversion, leave the type conversion and remove |
| -- the side effects in the expression. This is important in several |
| -- circumstances: for change of representations, and also when this is a |
| -- view conversion to a smaller object, where gigi can end up creating |
| -- its own temporary of the wrong size. |
| |
| elsif Nkind (Exp) = N_Type_Conversion then |
| Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref); |
| goto Leave; |
| |
| -- If this is an unchecked conversion that Gigi can't handle, make |
| -- a copy or a use a renaming to capture the value. |
| |
| elsif Nkind (Exp) = N_Unchecked_Type_Conversion |
| and then not Safe_Unchecked_Type_Conversion (Exp) |
| then |
| if CW_Or_Has_Controlled_Part (Exp_Type) then |
| |
| -- Use a renaming to capture the expression, rather than create |
| -- a controlled temporary. |
| |
| Def_Id := Make_Temporary (Loc, 'R', Exp); |
| Res := New_Reference_To (Def_Id, Loc); |
| |
| Insert_Action (Exp, |
| Make_Object_Renaming_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Subtype_Mark => New_Reference_To (Exp_Type, Loc), |
| Name => Relocate_Node (Exp))); |
| |
| else |
| Def_Id := Make_Temporary (Loc, 'R', Exp); |
| Set_Etype (Def_Id, Exp_Type); |
| Res := New_Reference_To (Def_Id, Loc); |
| |
| E := |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Object_Definition => New_Reference_To (Exp_Type, Loc), |
| Constant_Present => not Is_Variable (Exp), |
| Expression => Relocate_Node (Exp)); |
| |
| Set_Assignment_OK (E); |
| Insert_Action (Exp, E); |
| end if; |
| |
| -- For expressions that denote objects, we can use a renaming scheme. |
| -- This is needed for correctness in the case of a volatile object of |
| -- a non-volatile type because the Make_Reference call of the "default" |
| -- approach would generate an illegal access value (an access value |
| -- cannot designate such an object - see Analyze_Reference). We skip |
| -- using this scheme if we have an object of a volatile type and we do |
| -- not have Name_Req set true (see comments above for Side_Effect_Free). |
| |
| -- In Ada 2012 a qualified expression is an object, but for purposes of |
| -- removing side effects it still need to be transformed into a separate |
| -- declaration, particularly if the expression is an aggregate. |
| |
| elsif Is_Object_Reference (Exp) |
| and then Nkind (Exp) /= N_Function_Call |
| and then Nkind (Exp) /= N_Qualified_Expression |
| and then (Name_Req or else not Treat_As_Volatile (Exp_Type)) |
| then |
| Def_Id := Make_Temporary (Loc, 'R', Exp); |
| |
| if Nkind (Exp) = N_Selected_Component |
| and then Nkind (Prefix (Exp)) = N_Function_Call |
| and then Is_Array_Type (Exp_Type) |
| then |
| -- Avoid generating a variable-sized temporary, by generating |
| -- the renaming declaration just for the function call. The |
| -- transformation could be refined to apply only when the array |
| -- component is constrained by a discriminant??? |
| |
| Res := |
| Make_Selected_Component (Loc, |
| Prefix => New_Occurrence_Of (Def_Id, Loc), |
| Selector_Name => Selector_Name (Exp)); |
| |
| Insert_Action (Exp, |
| Make_Object_Renaming_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Subtype_Mark => |
| New_Reference_To (Base_Type (Etype (Prefix (Exp))), Loc), |
| Name => Relocate_Node (Prefix (Exp)))); |
| |
| else |
| Res := New_Reference_To (Def_Id, Loc); |
| |
| Insert_Action (Exp, |
| Make_Object_Renaming_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Subtype_Mark => New_Reference_To (Exp_Type, Loc), |
| Name => Relocate_Node (Exp))); |
| end if; |
| |
| -- If this is a packed reference, or a selected component with |
| -- a non-standard representation, a reference to the temporary |
| -- will be replaced by a copy of the original expression (see |
| -- Exp_Ch2.Expand_Renaming). Otherwise the temporary must be |
| -- elaborated by gigi, and is of course not to be replaced in-line |
| -- by the expression it renames, which would defeat the purpose of |
| -- removing the side-effect. |
| |
| if Nkind_In (Exp, N_Selected_Component, N_Indexed_Component) |
| and then Has_Non_Standard_Rep (Etype (Prefix (Exp))) |
| then |
| null; |
| else |
| Set_Is_Renaming_Of_Object (Def_Id, False); |
| end if; |
| |
| -- Otherwise we generate a reference to the value |
| |
| else |
| -- An expression which is in Alfa mode is considered side effect free |
| -- if the resulting value is captured by a variable or a constant. |
| |
| if Alfa_Mode and then Nkind (Parent (Exp)) = N_Object_Declaration then |
| goto Leave; |
| end if; |
| |
| -- Special processing for function calls that return a limited type. |
| -- We need to build a declaration that will enable build-in-place |
| -- expansion of the call. This is not done if the context is already |
| -- an object declaration, to prevent infinite recursion. |
| |
| -- This is relevant only in Ada 2005 mode. In Ada 95 programs we have |
| -- to accommodate functions returning limited objects by reference. |
| |
| if Ada_Version >= Ada_2005 |
| and then Nkind (Exp) = N_Function_Call |
| and then Is_Immutably_Limited_Type (Etype (Exp)) |
| and then Nkind (Parent (Exp)) /= N_Object_Declaration |
| then |
| declare |
| Obj : constant Entity_Id := Make_Temporary (Loc, 'F', Exp); |
| Decl : Node_Id; |
| |
| begin |
| Decl := |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Obj, |
| Object_Definition => New_Occurrence_Of (Exp_Type, Loc), |
| Expression => Relocate_Node (Exp)); |
| |
| Insert_Action (Exp, Decl); |
| Set_Etype (Obj, Exp_Type); |
| Rewrite (Exp, New_Occurrence_Of (Obj, Loc)); |
| goto Leave; |
| end; |
| end if; |
| |
| Def_Id := Make_Temporary (Loc, 'R', Exp); |
| Set_Etype (Def_Id, Exp_Type); |
| |
| -- The regular expansion of functions with side effects involves the |
| -- generation of an access type to capture the return value found on |
| -- the secondary stack. Since Alfa (and why) cannot process access |
| -- types, use a different approach which ignores the secondary stack |
| -- and "copies" the returned object. |
| |
| if Alfa_Mode then |
| Res := New_Reference_To (Def_Id, Loc); |
| Ref_Type := Exp_Type; |
| |
| -- Regular expansion utilizing an access type and 'reference |
| |
| else |
| Res := |
| Make_Explicit_Dereference (Loc, |
| Prefix => New_Reference_To (Def_Id, Loc)); |
| |
| -- Generate: |
| -- type Ann is access all <Exp_Type>; |
| |
| Ref_Type := Make_Temporary (Loc, 'A'); |
| |
| Ptr_Typ_Decl := |
| Make_Full_Type_Declaration (Loc, |
| Defining_Identifier => Ref_Type, |
| Type_Definition => |
| Make_Access_To_Object_Definition (Loc, |
| All_Present => True, |
| Subtype_Indication => |
| New_Reference_To (Exp_Type, Loc))); |
| |
| Insert_Action (Exp, Ptr_Typ_Decl); |
| end if; |
| |
| E := Exp; |
| if Nkind (E) = N_Explicit_Dereference then |
| New_Exp := Relocate_Node (Prefix (E)); |
| else |
| E := Relocate_Node (E); |
| |
| -- Do not generate a 'reference in Alfa mode since the access type |
| -- is not created in the first place. |
| |
| if Alfa_Mode then |
| New_Exp := E; |
| |
| -- Otherwise generate reference, marking the value as non-null |
| -- since we know it cannot be null and we don't want a check. |
| |
| else |
| New_Exp := Make_Reference (Loc, E); |
| Set_Is_Known_Non_Null (Def_Id); |
| end if; |
| end if; |
| |
| if Is_Delayed_Aggregate (E) then |
| |
| -- The expansion of nested aggregates is delayed until the |
| -- enclosing aggregate is expanded. As aggregates are often |
| -- qualified, the predicate applies to qualified expressions as |
| -- well, indicating that the enclosing aggregate has not been |
| -- expanded yet. At this point the aggregate is part of a |
| -- stand-alone declaration, and must be fully expanded. |
| |
| if Nkind (E) = N_Qualified_Expression then |
| Set_Expansion_Delayed (Expression (E), False); |
| Set_Analyzed (Expression (E), False); |
| else |
| Set_Expansion_Delayed (E, False); |
| end if; |
| |
| Set_Analyzed (E, False); |
| end if; |
| |
| Insert_Action (Exp, |
| Make_Object_Declaration (Loc, |
| Defining_Identifier => Def_Id, |
| Object_Definition => New_Reference_To (Ref_Type, Loc), |
| Constant_Present => True, |
| Expression => New_Exp)); |
| end if; |
| |
| -- Preserve the Assignment_OK flag in all copies, since at least one |
| -- copy may be used in a context where this flag must be set (otherwise |
| -- why would the flag be set in the first place). |
| |
| Set_Assignment_OK (Res, Assignment_OK (Exp)); |
| |
| -- Finally rewrite the original expression and we are done |
| |
| Rewrite (Exp, Res); |
| Analyze_And_Resolve (Exp, Exp_Type); |
| |
| <<Leave>> |
| Scope_Suppress := Svg_Suppress; |
| end Remove_Side_Effects; |
| |
| --------------------------- |
| -- Represented_As_Scalar -- |
| --------------------------- |
| |
| function Represented_As_Scalar (T : Entity_Id) return Boolean is |
| UT : constant Entity_Id := Underlying_Type (T); |
| begin |
| return Is_Scalar_Type (UT) |
| or else (Is_Bit_Packed_Array (UT) |
| and then Is_Scalar_Type (Packed_Array_Type (UT))); |
| end Represented_As_Scalar; |
| |
| ------------------------------ |
| -- Requires_Cleanup_Actions -- |
| ------------------------------ |
| |
| function Requires_Cleanup_Actions |
| (N : Node_Id; |
| Lib_Level : Boolean) return Boolean |
| is |
| At_Lib_Level : constant Boolean := |
| Lib_Level |
| and then Nkind_In (N, N_Package_Body, |
| N_Package_Specification); |
| -- N is at the library level if the top-most context is a package and |
| -- the path taken to reach N does not inlcude non-package constructs. |
| |
| begin |
| case Nkind (N) is |
| when N_Accept_Statement | |
| N_Block_Statement | |
| N_Entry_Body | |
| N_Package_Body | |
| N_Protected_Body | |
| N_Subprogram_Body | |
| N_Task_Body => |
| return |
| Requires_Cleanup_Actions (Declarations (N), At_Lib_Level, True) |
| or else |
| (Present (Handled_Statement_Sequence (N)) |
| and then |
| Requires_Cleanup_Actions |
| (Statements (Handled_Statement_Sequence (N)), |
| At_Lib_Level, True)); |
| |
| when N_Package_Specification => |
| return |
| Requires_Cleanup_Actions |
| (Visible_Declarations (N), At_Lib_Level, True) |
| or else |
| Requires_Cleanup_Actions |
| (Private_Declarations (N), At_Lib_Level, True); |
| |
| when others => |
| return False; |
| end case; |
| end Requires_Cleanup_Actions; |
| |
| ------------------------------ |
| -- Requires_Cleanup_Actions -- |
| ------------------------------ |
| |
| function Requires_Cleanup_Actions |
| (L : List_Id; |
| Lib_Level : Boolean; |
| Nested_Constructs : Boolean) return Boolean |
| is |
| Decl : Node_Id; |
| Expr : Node_Id; |
| Obj_Id : Entity_Id; |
| Obj_Typ : Entity_Id; |
| Pack_Id : Entity_Id; |
| Typ : Entity_Id; |
| |
| begin |
| if No (L) |
| or else Is_Empty_List (L) |
| then |
| return False; |
| end if; |
| |
| Decl := First (L); |
| while Present (Decl) loop |
| |
| -- Library-level tagged types |
| |
| if Nkind (Decl) = N_Full_Type_Declaration then |
| Typ := Defining_Identifier (Decl); |
| |
| if Is_Tagged_Type (Typ) |
| and then Is_Library_Level_Entity (Typ) |
| and then Convention (Typ) = Convention_Ada |
| and then Present (Access_Disp_Table (Typ)) |
| and then RTE_Available (RE_Unregister_Tag) |
| and then not No_Run_Time_Mode |
| and then not Is_Abstract_Type (Typ) |
| then |
| return True; |
| end if; |
| |
| -- Regular object declarations |
| |
| elsif Nkind (Decl) = N_Object_Declaration then |
| Obj_Id := Defining_Identifier (Decl); |
| Obj_Typ := Base_Type (Etype (Obj_Id)); |
| Expr := Expression (Decl); |
| |
| -- Bypass any form of processing for objects which have their |
| -- finalization disabled. This applies only to objects at the |
| -- library level. |
| |
| if Lib_Level and then Finalize_Storage_Only (Obj_Typ) then |
| null; |
| |
| -- Transient variables are treated separately in order to minimize |
| -- the size of the generated code. See Exp_Ch7.Process_Transient_ |
| -- Objects. |
| |
| elsif Is_Processed_Transient (Obj_Id) then |
| null; |
| |
| -- The object is of the form: |
| -- Obj : Typ [:= Expr]; |
| -- |
| -- Do not process the incomplete view of a deferred constant. Do |
| -- not consider tag-to-class-wide conversions. |
| |
| elsif not Is_Imported (Obj_Id) |
| and then Needs_Finalization (Obj_Typ) |
| and then not (Ekind (Obj_Id) = E_Constant |
| and then not Has_Completion (Obj_Id)) |
| and then not Is_Tag_To_Class_Wide_Conversion (Obj_Id) |
| then |
| return True; |
| |
| -- The object is of the form: |
| -- Obj : Access_Typ := Non_BIP_Function_Call'reference; |
| -- |
| -- Obj : Access_Typ := |
| -- BIP_Function_Call (BIPalloc => 2, ...)'reference; |
| |
| elsif Is_Access_Type (Obj_Typ) |
| and then Needs_Finalization |
| (Available_View (Designated_Type (Obj_Typ))) |
| and then Present (Expr) |
| and then |
| (Is_Secondary_Stack_BIP_Func_Call (Expr) |
| or else |
| (Is_Non_BIP_Func_Call (Expr) |
| and then not Is_Related_To_Func_Return (Obj_Id))) |
| then |
| return True; |
| |
| -- Processing for "hook" objects generated for controlled |
| -- transients declared inside an Expression_With_Actions. |
| |
| elsif Is_Access_Type (Obj_Typ) |
| and then Present (Status_Flag_Or_Transient_Decl (Obj_Id)) |
| and then Nkind (Status_Flag_Or_Transient_Decl (Obj_Id)) = |
| N_Object_Declaration |
| and then Is_Finalizable_Transient |
| (Status_Flag_Or_Transient_Decl (Obj_Id), Decl) |
| then |
| return True; |
| |
| -- Processing for intermediate results of if expressions where |
| -- one of the alternatives uses a controlled function call. |
| |
| elsif Is_Access_Type (Obj_Typ) |
| and then Present (Status_Flag_Or_Transient_Decl (Obj_Id)) |
| and then Nkind (Status_Flag_Or_Transient_Decl (Obj_Id)) = |
| N_Defining_Identifier |
| and then Present (Expr) |
| and then Nkind (Expr) = N_Null |
| then |
| return True; |
| |
| -- Simple protected objects which use type System.Tasking. |
| -- Protected_Objects.Protection to manage their locks should be |
| -- treated as controlled since they require manual cleanup. |
| |
| elsif Ekind (Obj_Id) = E_Variable |
| and then |
| (Is_Simple_Protected_Type (Obj_Typ) |
| or else Has_Simple_Protected_Object (Obj_Typ)) |
| then |
| return True; |
| end if; |
| |
| -- Specific cases of object renamings |
| |
| elsif Nkind (Decl) = N_Object_Renaming_Declaration then |
| Obj_Id := Defining_Identifier (Decl); |
| Obj_Typ := Base_Type (Etype (Obj_Id)); |
| |
| -- Bypass any form of processing for objects which have their |
| -- finalization disabled. This applies only to objects at the |
| -- library level. |
| |
| if Lib_Level and then Finalize_Storage_Only (Obj_Typ) then |
| null; |
| |
| -- Return object of a build-in-place function. This case is |
| -- recognized and marked by the expansion of an extended return |
| -- statement (see Expand_N_Extended_Return_Statement). |
| |
| elsif Needs_Finalization (Obj_Typ) |
| and then Is_Return_Object (Obj_Id) |
| and then Present (Status_Flag_Or_Transient_Decl (Obj_Id)) |
| then |
| return True; |
| |
| -- Detect a case where a source object has been initialized by |
| -- a controlled function call or another object which was later |
| -- rewritten as a class-wide conversion of Ada.Tags.Displace. |
| |
| -- Obj1 : CW_Type := Src_Obj; |
| -- Obj2 : CW_Type := Function_Call (...); |
| |
| -- Obj1 : CW_Type renames (... Ada.Tags.Displace (Src_Obj)); |
| -- Tmp : ... := Function_Call (...)'reference; |
| -- Obj2 : CW_Type renames (... Ada.Tags.Displace (Tmp)); |
| |
| elsif Is_Displacement_Of_Object_Or_Function_Result (Obj_Id) then |
| return True; |
| end if; |
| |
| -- Inspect the freeze node of an access-to-controlled type and look |
| -- for a delayed finalization master. This case arises when the |
| -- freeze actions are inserted at a later time than the expansion of |
| -- the context. Since Build_Finalizer is never called on a single |
| -- construct twice, the master will be ultimately left out and never |
| -- finalized. This is also needed for freeze actions of designated |
| -- types themselves, since in some cases the finalization master is |
| -- associated with a designated type's freeze node rather than that |
| -- of the access type (see handling for freeze actions in |
| -- Build_Finalization_Master). |
| |
| elsif Nkind (Decl) = N_Freeze_Entity |
| and then Present (Actions (Decl)) |
| then |
| Typ := Entity (Decl); |
| |
| if ((Is_Access_Type (Typ) |
| and then not Is_Access_Subprogram_Type (Typ) |
| and then Needs_Finalization |
| (Available_View (Designated_Type (Typ)))) |
| or else |
| (Is_Type (Typ) |
| and then Needs_Finalization (Typ))) |
| and then Requires_Cleanup_Actions |
| (Actions (Decl), Lib_Level, Nested_Constructs) |
| then |
| return True; |
| end if; |
| |
| -- Nested package declarations |
| |
| elsif Nested_Constructs |
| and then Nkind (Decl) = N_Package_Declaration |
| then |
| Pack_Id := Defining_Unit_Name (Specification (Decl)); |
| |
| if Nkind (Pack_Id) = N_Defining_Program_Unit_Name then |
| Pack_Id := Defining_Identifier (Pack_Id); |
| end if; |
| |
| if Ekind (Pack_Id) /= E_Generic_Package |
| and then |
| Requires_Cleanup_Actions (Specification (Decl), Lib_Level) |
| then |
| return True; |
| end if; |
| |
| -- Nested package bodies |
| |
| elsif Nested_Constructs and then Nkind (Decl) = N_Package_Body then |
| Pack_Id := Corresponding_Spec (Decl); |
| |
| if Ekind (Pack_Id) /= E_Generic_Package |
| and then Requires_Cleanup_Actions (Decl, Lib_Level) |
| then |
| return True; |
| end if; |
| end if; |
| |
| Next (Decl); |
| end loop; |
| |
| return False; |
| end Requires_Cleanup_Actions; |
| |
| ------------------------------------ |
| -- Safe_Unchecked_Type_Conversion -- |
| ------------------------------------ |
| |
| -- Note: this function knows quite a bit about the exact requirements of |
| -- Gigi with respect to unchecked type conversions, and its code must be |
| -- coordinated with any changes in Gigi in this area. |
| |
| -- The above requirements should be documented in Sinfo ??? |
| |
| function Safe_Unchecked_Type_Conversion (Exp : Node_Id) return Boolean is |
| Otyp : Entity_Id; |
| Ityp : Entity_Id; |
| Oalign : Uint; |
| Ialign : Uint; |
| Pexp : constant Node_Id := Parent (Exp); |
| |
| begin |
| -- If the expression is the RHS of an assignment or object declaration |
| -- we are always OK because there will always be a target. |
| |
| -- Object renaming declarations, (generated for view conversions of |
| -- actuals in inlined calls), like object declarations, provide an |
| -- explicit type, and are safe as well. |
| |
| if (Nkind (Pexp) = N_Assignment_Statement |
| and then Expression (Pexp) = Exp) |
| or else Nkind_In (Pexp, N_Object_Declaration, |
| N_Object_Renaming_Declaration) |
| then |
| return True; |
| |
| -- If the expression is the prefix of an N_Selected_Component we should |
| -- also be OK because GCC knows to look inside the conversion except if |
| -- the type is discriminated. We assume that we are OK anyway if the |
| -- type is not set yet or if it is controlled since we can't afford to |
| -- introduce a temporary in this case. |
| |
| elsif Nkind (Pexp) = N_Selected_Component |
| and then Prefix (Pexp) = Exp |
| then |
| if No (Etype (Pexp)) then |
| return True; |
| else |
| return |
| not Has_Discriminants (Etype (Pexp)) |
| or else Is_Constrained (Etype (Pexp)); |
| end if; |
| end if; |
| |
| -- Set the output type, this comes from Etype if it is set, otherwise we |
| -- take it from the subtype mark, which we assume was already fully |
| -- analyzed. |
| |
| if Present (Etype (Exp)) then |
| Otyp := Etype (Exp); |
| else |
| Otyp := Entity (Subtype_Mark (Exp)); |
| end if; |
| |
| -- The input type always comes from the expression, and we assume |
| -- this is indeed always analyzed, so we can simply get the Etype. |
| |
| Ityp := Etype (Expression (Exp)); |
| |
| -- Initialize alignments to unknown so far |
| |
| Oalign := No_Uint; |
| Ialign := No_Uint; |
| |
| -- Replace a concurrent type by its corresponding record type and each |
| -- type by its underlying type and do the tests on those. The original |
| -- type may be a private type whose completion is a concurrent type, so |
| -- find the underlying type first. |
| |
| if Present (Underlying_Type (Otyp)) then |
| Otyp := Underlying_Type (Otyp); |
| end if; |
| |
| if Present (Underlying_Type (Ityp)) then |
| Ityp := Underlying_Type (Ityp); |
| end if; |
| |
| if Is_Concurrent_Type (Otyp) then |
| Otyp := Corresponding_Record_Type (Otyp); |
| end if; |
| |
| if Is_Concurrent_Type (Ityp) then |
| Ityp := Corresponding_Record_Type (Ityp); |
| end if; |
| |
| -- If the base types are the same, we know there is no problem since |
| -- this conversion will be a noop. |
| |
| if Implementation_Base_Type (Otyp) = Implementation_Base_Type (Ityp) then |
| return True; |
| |
| -- Same if this is an upwards conversion of an untagged type, and there |
| -- are no constraints involved (could be more general???) |
| |
| elsif Etype (Ityp) = Otyp |
| and then not Is_Tagged_Type (Ityp) |
| and then not Has_Discriminants (Ityp) |
| and then No (First_Rep_Item (Base_Type (Ityp))) |
| then |
| return True; |
| |
| -- If the expression has an access type (object or subprogram) we assume |
| -- that the conversion is safe, because the size of the target is safe, |
| -- even if it is a record (which might be treated as having unknown size |
| -- at this point). |
| |
| elsif Is_Access_Type (Ityp) then |
| return True; |
| |
| -- If the size of output type is known at compile time, there is never |
| -- a problem. Note that unconstrained records are considered to be of |
| -- known size, but we can't consider them that way here, because we are |
| -- talking about the actual size of the object. |
| |
| -- We also make sure that in addition to the size being known, we do not |
| -- have a case which might generate an embarrassingly large temp in |
| -- stack checking mode. |
| |
| elsif Size_Known_At_Compile_Time (Otyp) |
| and then |
| (not Stack_Checking_Enabled |
| or else not May_Generate_Large_Temp (Otyp)) |
| and then not (Is_Record_Type (Otyp) and then not Is_Constrained (Otyp)) |
| then |
| return True; |
| |
| -- If either type is tagged, then we know the alignment is OK so |
| -- Gigi will be able to use pointer punning. |
| |
| elsif Is_Tagged_Type (Otyp) or else Is_Tagged_Type (Ityp) then |
| return True; |
| |
| -- If either type is a limited record type, we cannot do a copy, so say |
| -- safe since there's nothing else we can do. |
| |
| elsif Is_Limited_Record (Otyp) or else Is_Limited_Record (Ityp) then |
| return True; |
| |
| -- Conversions to and from packed array types are always ignored and |
| -- hence are safe. |
| |
| elsif Is_Packed_Array_Type (Otyp) |
| or else Is_Packed_Array_Type (Ityp) |
| then |
| return True; |
| end if; |
| |
| -- The only other cases known to be safe is if the input type's |
| -- alignment is known to be at least the maximum alignment for the |
| -- target or if both alignments are known and the output type's |
| -- alignment is no stricter than the input's. We can use the component |
| -- type alignement for an array if a type is an unpacked array type. |
| |
| if Present (Alignment_Clause (Otyp)) then |
| Oalign := Expr_Value (Expression (Alignment_Clause (Otyp))); |
| |
| elsif Is_Array_Type (Otyp) |
| and then Present (Alignment_Clause (Component_Type (Otyp))) |
| then |
| Oalign := Expr_Value (Expression (Alignment_Clause |
| (Component_Type (Otyp)))); |
| end if; |
| |
| if Present (Alignment_Clause (Ityp)) then |
| Ialign := Expr_Value (Expression (Alignment_Clause (Ityp))); |
| |
| elsif Is_Array_Type (Ityp) |
| and then Present (Alignment_Clause (Component_Type (Ityp))) |
| then |
| Ialign := Expr_Value (Expression (Alignment_Clause |
| (Component_Type (Ityp)))); |
| end if; |
| |
| if Ialign /= No_Uint and then Ialign > Maximum_Alignment then |
| return True; |
| |
| elsif Ialign /= No_Uint and then Oalign /= No_Uint |
| and then Ialign <= Oalign |
| then |
| return True; |
| |
| -- Otherwise, Gigi cannot handle this and we must make a temporary |
| |
| else |
| return False; |
| end if; |
| end Safe_Unchecked_Type_Conversion; |
| |
| --------------------------------- |
| -- Set_Current_Value_Condition -- |
| --------------------------------- |
| |
| -- Note: the implementation of this procedure is very closely tied to the |
| -- implementation of Get_Current_Value_Condition. Here we set required |
| -- Current_Value fields, and in Get_Current_Value_Condition, we interpret |
| -- them, so they must have a consistent view. |
| |
| procedure Set_Current_Value_Condition (Cnode : Node_Id) is |
| |
| procedure Set_Entity_Current_Value (N : Node_Id); |
| -- If N is an entity reference, where the entity is of an appropriate |
| -- kind, then set the current value of this entity to Cnode, unless |
| -- there is already a definite value set there. |
| |
| procedure Set_Expression_Current_Value (N : Node_Id); |
| -- If N is of an appropriate form, sets an appropriate entry in current |
| -- value fields of relevant entities. Multiple entities can be affected |
| -- in the case of an AND or AND THEN. |
| |
| ------------------------------ |
| -- Set_Entity_Current_Value -- |
| ------------------------------ |
| |
| procedure Set_Entity_Current_Value (N : Node_Id) is |
| begin |
| if Is_Entity_Name (N) then |
| declare |
| Ent : constant Entity_Id := Entity (N); |
| |
| begin |
| -- Don't capture if not safe to do so |
| |
| if not Safe_To_Capture_Value (N, Ent, Cond => True) then |
| return; |
| end if; |
| |
| -- Here we have a case where the Current_Value field may need |
| -- to be set. We set it if it is not already set to a compile |
| -- time expression value. |
| |
| -- Note that this represents a decision that one condition |
| -- blots out another previous one. That's certainly right if |
| -- they occur at the same level. If the second one is nested, |
| -- then the decision is neither right nor wrong (it would be |
| -- equally OK to leave the outer one in place, or take the new |
| -- inner one. Really we should record both, but our data |
| -- structures are not that elaborate. |
| |
| if Nkind (Current_Value (Ent)) not in N_Subexpr then |
| Set_Current_Value (Ent, Cnode); |
| end if; |
| end; |
| end if; |
| end Set_Entity_Current_Value; |
| |
| ---------------------------------- |
| -- Set_Expression_Current_Value -- |
| ---------------------------------- |
| |
| procedure Set_Expression_Current_Value (N : Node_Id) is |
| Cond : Node_Id; |
| |
| begin |
| Cond := N; |
| |
| -- Loop to deal with (ignore for now) any NOT operators present. The |
| -- presence of NOT operators will be handled properly when we call |
| -- Get_Current_Value_Condition. |
| |
| while Nkind (Cond) = N_Op_Not loop |
| Cond := Right_Opnd (Cond); |
| end loop; |
| |
| -- For an AND or AND THEN, recursively process operands |
| |
| if Nkind (Cond) = N_Op_And or else Nkind (Cond) = N_And_Then then |
| Set_Expression_Current_Value (Left_Opnd (Cond)); |
| Set_Expression_Current_Value (Right_Opnd (Cond)); |
| return; |
| end if; |
| |
| -- Check possible relational operator |
| |
| if Nkind (Cond) in N_Op_Compare then |
| if Compile_Time_Known_Value (Right_Opnd (Cond)) then |
| Set_Entity_Current_Value (Left_Opnd (Cond)); |
| elsif Compile_Time_Known_Value (Left_Opnd (Cond)) then |
| Set_Entity_Current_Value (Right_Opnd (Cond)); |
| end if; |
| |
| -- Check possible boolean variable reference |
| |
| else |
| Set_Entity_Current_Value (Cond); |
| end if; |
| end Set_Expression_Current_Value; |
| |
| -- Start of processing for Set_Current_Value_Condition |
| |
| begin |
| Set_Expression_Current_Value (Condition (Cnode)); |
| end Set_Current_Value_Condition; |
| |
| -------------------------- |
| -- Set_Elaboration_Flag -- |
| -------------------------- |
| |
| procedure Set_Elaboration_Flag (N : Node_Id; Spec_Id : Entity_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| Ent : constant Entity_Id := Elaboration_Entity (Spec_Id); |
| Asn : Node_Id; |
| |
| begin |
| if Present (Ent) then |
| |
| -- Nothing to do if at the compilation unit level, because in this |
| -- case the flag is set by the binder generated elaboration routine. |
| |
| if Nkind (Parent (N)) = N_Compilation_Unit then |
| null; |
| |
| -- Here we do need to generate an assignment statement |
| |
| else |
| Check_Restriction (No_Elaboration_Code, N); |
| Asn := |
| Make_Assignment_Statement (Loc, |
| Name => New_Occurrence_Of (Ent, Loc), |
| Expression => Make_Integer_Literal (Loc, Uint_1)); |
| |
| if Nkind (Parent (N)) = N_Subunit then |
| Insert_After (Corresponding_Stub (Parent (N)), Asn); |
| else |
| Insert_After (N, Asn); |
| end if; |
| |
| Analyze (Asn); |
| |
| -- Kill current value indication. This is necessary because the |
| -- tests of this flag are inserted out of sequence and must not |
| -- pick up bogus indications of the wrong constant value. |
| |
| Set_Current_Value (Ent, Empty); |
| end if; |
| end if; |
| end Set_Elaboration_Flag; |
| |
| ---------------------------- |
| -- Set_Renamed_Subprogram -- |
| ---------------------------- |
| |
| procedure Set_Renamed_Subprogram (N : Node_Id; E : Entity_Id) is |
| begin |
| -- If input node is an identifier, we can just reset it |
| |
| if Nkind (N) = N_Identifier then |
| Set_Chars (N, Chars (E)); |
| Set_Entity (N, E); |
| |
| -- Otherwise we have to do a rewrite, preserving Comes_From_Source |
| |
| else |
| declare |
| CS : constant Boolean := Comes_From_Source (N); |
| begin |
| Rewrite (N, Make_Identifier (Sloc (N), Chars (E))); |
| Set_Entity (N, E); |
| Set_Comes_From_Source (N, CS); |
| Set_Analyzed (N, True); |
| end; |
| end if; |
| end Set_Renamed_Subprogram; |
| |
| ---------------------------------- |
| -- Silly_Boolean_Array_Not_Test -- |
| ---------------------------------- |
| |
| -- This procedure implements an odd and silly test. We explicitly check |
| -- for the case where the 'First of the component type is equal to the |
| -- 'Last of this component type, and if this is the case, we make sure |
| -- that constraint error is raised. The reason is that the NOT is bound |
| -- to cause CE in this case, and we will not otherwise catch it. |
| |
| -- No such check is required for AND and OR, since for both these cases |
| -- False op False = False, and True op True = True. For the XOR case, |
| -- see Silly_Boolean_Array_Xor_Test. |
| |
| -- Believe it or not, this was reported as a bug. Note that nearly always, |
| -- the test will evaluate statically to False, so the code will be |
| -- statically removed, and no extra overhead caused. |
| |
| procedure Silly_Boolean_Array_Not_Test (N : Node_Id; T : Entity_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| CT : constant Entity_Id := Component_Type (T); |
| |
| begin |
| -- The check we install is |
| |
| -- constraint_error when |
| -- component_type'first = component_type'last |
| -- and then array_type'Length /= 0) |
| |
| -- We need the last guard because we don't want to raise CE for empty |
| -- arrays since no out of range values result. (Empty arrays with a |
| -- component type of True .. True -- very useful -- even the ACATS |
| -- does not test that marginal case!) |
| |
| Insert_Action (N, |
| Make_Raise_Constraint_Error (Loc, |
| Condition => |
| Make_And_Then (Loc, |
| Left_Opnd => |
| Make_Op_Eq (Loc, |
| Left_Opnd => |
| Make_Attribute_Reference (Loc, |
| Prefix => New_Occurrence_Of (CT, Loc), |
| Attribute_Name => Name_First), |
| |
| Right_Opnd => |
| Make_Attribute_Reference (Loc, |
| Prefix => New_Occurrence_Of (CT, Loc), |
| Attribute_Name => Name_Last)), |
| |
| Right_Opnd => Make_Non_Empty_Check (Loc, Right_Opnd (N))), |
| Reason => CE_Range_Check_Failed)); |
| end Silly_Boolean_Array_Not_Test; |
| |
| ---------------------------------- |
| -- Silly_Boolean_Array_Xor_Test -- |
| ---------------------------------- |
| |
| -- This procedure implements an odd and silly test. We explicitly check |
| -- for the XOR case where the component type is True .. True, since this |
| -- will raise constraint error. A special check is required since CE |
| -- will not be generated otherwise (cf Expand_Packed_Not). |
| |
| -- No such check is required for AND and OR, since for both these cases |
| -- False op False = False, and True op True = True, and no check is |
| -- required for the case of False .. False, since False xor False = False. |
| -- See also Silly_Boolean_Array_Not_Test |
| |
| procedure Silly_Boolean_Array_Xor_Test (N : Node_Id; T : Entity_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| CT : constant Entity_Id := Component_Type (T); |
| |
| begin |
| -- The check we install is |
| |
| -- constraint_error when |
| -- Boolean (component_type'First) |
| -- and then Boolean (component_type'Last) |
| -- and then array_type'Length /= 0) |
| |
| -- We need the last guard because we don't want to raise CE for empty |
| -- arrays since no out of range values result (Empty arrays with a |
| -- component type of True .. True -- very useful -- even the ACATS |
| -- does not test that marginal case!). |
| |
| Insert_Action (N, |
| Make_Raise_Constraint_Error (Loc, |
| Condition => |
| Make_And_Then (Loc, |
| Left_Opnd => |
| Make_And_Then (Loc, |
| Left_Opnd => |
| Convert_To (Standard_Boolean, |
| Make_Attribute_Reference (Loc, |
| Prefix => New_Occurrence_Of (CT, Loc), |
| Attribute_Name => Name_First)), |
| |
| Right_Opnd => |
| Convert_To (Standard_Boolean, |
| Make_Attribute_Reference (Loc, |
| Prefix => New_Occurrence_Of (CT, Loc), |
| Attribute_Name => Name_Last))), |
| |
| Right_Opnd => Make_Non_Empty_Check (Loc, Right_Opnd (N))), |
| Reason => CE_Range_Check_Failed)); |
| end Silly_Boolean_Array_Xor_Test; |
| |
| -------------------------- |
| -- Target_Has_Fixed_Ops -- |
| -------------------------- |
| |
| Integer_Sized_Small : Ureal; |
| -- Set to 2.0 ** -(Integer'Size - 1) the first time that this function is |
| -- called (we don't want to compute it more than once!) |
| |
| Long_Integer_Sized_Small : Ureal; |
| -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this function |
| -- is called (we don't want to compute it more than once) |
| |
| First_Time_For_THFO : Boolean := True; |
| -- Set to False after first call (if Fractional_Fixed_Ops_On_Target) |
| |
| function Target_Has_Fixed_Ops |
| (Left_Typ : Entity_Id; |
| Right_Typ : Entity_Id; |
| Result_Typ : Entity_Id) return Boolean |
| is |
| function Is_Fractional_Type (Typ : Entity_Id) return Boolean; |
| -- Return True if the given type is a fixed-point type with a small |
| -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have |
| -- an absolute value less than 1.0. This is currently limited to |
| -- fixed-point types that map to Integer or Long_Integer. |
| |
| ------------------------ |
| -- Is_Fractional_Type -- |
| ------------------------ |
| |
| function Is_Fractional_Type (Typ : Entity_Id) return Boolean is |
| begin |
| if Esize (Typ) = Standard_Integer_Size then |
| return Small_Value (Typ) = Integer_Sized_Small; |
| |
| elsif Esize (Typ) = Standard_Long_Integer_Size then |
| return Small_Value (Typ) = Long_Integer_Sized_Small; |
| |
| else |
| return False; |
| end if; |
| end Is_Fractional_Type; |
| |
| -- Start of processing for Target_Has_Fixed_Ops |
| |
| begin |
| -- Return False if Fractional_Fixed_Ops_On_Target is false |
| |
| if not Fractional_Fixed_Ops_On_Target then |
| return False; |
| end if; |
| |
| -- Here the target has Fractional_Fixed_Ops, if first time, compute |
| -- standard constants used by Is_Fractional_Type. |
| |
| if First_Time_For_THFO then |
| First_Time_For_THFO := False; |
| |
| Integer_Sized_Small := |
| UR_From_Components |
| (Num => Uint_1, |
| Den => UI_From_Int (Standard_Integer_Size - 1), |
| Rbase => 2); |
| |
| Long_Integer_Sized_Small := |
| UR_From_Components |
| (Num => Uint_1, |
| Den => UI_From_Int (Standard_Long_Integer_Size - 1), |
| Rbase => 2); |
| end if; |
| |
| -- Return True if target supports fixed-by-fixed multiply/divide for |
| -- fractional fixed-point types (see Is_Fractional_Type) and the operand |
| -- and result types are equivalent fractional types. |
| |
| return Is_Fractional_Type (Base_Type (Left_Typ)) |
| and then Is_Fractional_Type (Base_Type (Right_Typ)) |
| and then Is_Fractional_Type (Base_Type (Result_Typ)) |
| and then Esize (Left_Typ) = Esize (Right_Typ) |
| and then Esize (Left_Typ) = Esize (Result_Typ); |
| end Target_Has_Fixed_Ops; |
| |
| ------------------------------------------ |
| -- Type_May_Have_Bit_Aligned_Components -- |
| ------------------------------------------ |
| |
| function Type_May_Have_Bit_Aligned_Components |
| (Typ : Entity_Id) return Boolean |
| is |
| begin |
| -- Array type, check component type |
| |
| if Is_Array_Type (Typ) then |
| return |
| Type_May_Have_Bit_Aligned_Components (Component_Type (Typ)); |
| |
| -- Record type, check components |
| |
| elsif Is_Record_Type (Typ) then |
| declare |
| E : Entity_Id; |
| |
| begin |
| E := First_Component_Or_Discriminant (Typ); |
| while Present (E) loop |
| if Component_May_Be_Bit_Aligned (E) |
| or else Type_May_Have_Bit_Aligned_Components (Etype (E)) |
| then |
| return True; |
| end if; |
| |
| Next_Component_Or_Discriminant (E); |
| end loop; |
| |
| return False; |
| end; |
| |
| -- Type other than array or record is always OK |
| |
| else |
| return False; |
| end if; |
| end Type_May_Have_Bit_Aligned_Components; |
| |
| ---------------------------------- |
| -- Within_Case_Or_If_Expression -- |
| ---------------------------------- |
| |
| function Within_Case_Or_If_Expression (N : Node_Id) return Boolean is |
| Par : Node_Id; |
| |
| begin |
| -- Locate an enclosing case or if expression. Note: these constructs can |
| -- get expanded into Expression_With_Actions, hence the need to test |
| -- using the original node. |
| |
| Par := N; |
| while Present (Par) loop |
| if Nkind_In (Original_Node (Par), N_Case_Expression, |
| N_If_Expression) |
| then |
| return True; |
| |
| -- Prevent the search from going too far |
| |
| elsif Nkind_In (Par, N_Entry_Body, |
| N_Package_Body, |
| N_Package_Declaration, |
| N_Protected_Body, |
| N_Subprogram_Body, |
| N_Task_Body) |
| then |
| return False; |
| end if; |
| |
| Par := Parent (Par); |
| end loop; |
| |
| return False; |
| end Within_Case_Or_If_Expression; |
| |
| ---------------------------- |
| -- Wrap_Cleanup_Procedure -- |
| ---------------------------- |
| |
| procedure Wrap_Cleanup_Procedure (N : Node_Id) is |
| Loc : constant Source_Ptr := Sloc (N); |
| Stseq : constant Node_Id := Handled_Statement_Sequence (N); |
| Stmts : constant List_Id := Statements (Stseq); |
| |
| begin |
| if Abort_Allowed then |
| Prepend_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer)); |
| Append_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer)); |
| end if; |
| end Wrap_Cleanup_Procedure; |
| |
| end Exp_Util; |