| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- E X P A N D E R -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2014, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 3, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNAT; see file COPYING3. If not, go to -- |
| -- http://www.gnu.org/licenses for a complete copy of the license. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Atree; use Atree; |
| with Debug_A; use Debug_A; |
| with Exp_Aggr; use Exp_Aggr; |
| with Exp_SPARK; use Exp_SPARK; |
| with Exp_Attr; use Exp_Attr; |
| with Exp_Ch2; use Exp_Ch2; |
| with Exp_Ch3; use Exp_Ch3; |
| with Exp_Ch4; use Exp_Ch4; |
| with Exp_Ch5; use Exp_Ch5; |
| with Exp_Ch6; use Exp_Ch6; |
| with Exp_Ch7; use Exp_Ch7; |
| with Exp_Ch8; use Exp_Ch8; |
| with Exp_Ch9; use Exp_Ch9; |
| with Exp_Ch11; use Exp_Ch11; |
| with Exp_Ch12; use Exp_Ch12; |
| with Exp_Ch13; use Exp_Ch13; |
| with Exp_Prag; use Exp_Prag; |
| with Opt; use Opt; |
| with Rtsfind; use Rtsfind; |
| with Sem; use Sem; |
| with Sem_Ch8; use Sem_Ch8; |
| with Sem_Util; use Sem_Util; |
| with Sinfo; use Sinfo; |
| with Table; |
| |
| package body Expander is |
| |
| ---------------- |
| -- Local Data -- |
| ---------------- |
| |
| -- The following table is used to save values of the Expander_Active flag |
| -- when they are saved by Expander_Mode_Save_And_Set. We use an extendible |
| -- table (which is a bit of overkill) because it is easier than figuring |
| -- out a maximum value or bothering with range checks. |
| |
| package Expander_Flags is new Table.Table ( |
| Table_Component_Type => Boolean, |
| Table_Index_Type => Int, |
| Table_Low_Bound => 0, |
| Table_Initial => 32, |
| Table_Increment => 200, |
| Table_Name => "Expander_Flags"); |
| |
| ------------ |
| -- Expand -- |
| ------------ |
| |
| procedure Expand (N : Node_Id) is |
| begin |
| -- If we were analyzing a default expression (or other spec expression) |
| -- the Full_Analysis flag must be off. If we are in expansion mode then |
| -- we must be performing a full analysis. If we are analyzing a generic |
| -- then Expansion must be off. |
| |
| pragma Assert |
| (not (Full_Analysis and then In_Spec_Expression) |
| and then (Full_Analysis or else not Expander_Active) |
| and then not (Inside_A_Generic and then Expander_Active)); |
| |
| -- The GNATprove_Mode flag indicates that a light expansion for formal |
| -- verification should be used. This expansion is never done inside |
| -- generics, because otherwise, this breaks the name resolution |
| -- mechanism for generic instances. |
| |
| if GNATprove_Mode then |
| if not Inside_A_Generic then |
| Expand_SPARK (N); |
| end if; |
| |
| Set_Analyzed (N, Full_Analysis); |
| |
| -- Regular expansion is normally followed by special handling for |
| -- transient scopes for unconstrained results, etc. but this is not |
| -- needed, and in general cannot be done correctly, in this mode, so |
| -- we are all done. |
| |
| return; |
| |
| -- There are three reasons for the Expander_Active flag to be false |
| |
| -- The first is when are not generating code. In this mode the |
| -- Full_Analysis flag indicates whether we are performing a complete |
| -- analysis, in which case Full_Analysis = True or a pre-analysis in |
| -- which case Full_Analysis = False. See the spec of Sem for more info |
| -- on this. |
| |
| -- The second reason for the Expander_Active flag to be False is that |
| -- we are performing a pre-analysis. During pre-analysis all expansion |
| -- activity is turned off to make sure nodes are semantically decorated |
| -- but no extra nodes are generated. This is for instance needed for |
| -- the first pass of aggregate semantic processing. Note that in this |
| -- case the Full_Analysis flag is set to False because the node will |
| -- subsequently be re-analyzed with expansion on (see the spec of sem). |
| |
| -- Finally, expansion is turned off in a regular compilation if there |
| -- are serious errors. In that case there will be no further expansion, |
| -- but one cleanup action may be required: if a transient scope was |
| -- created (e.g. for a function that returns an unconstrained type) the |
| -- scope may still be on the stack, and must be removed explicitly, |
| -- given that the expansion actions that would normally process it will |
| -- not take place. This prevents cascaded errors due to stack mismatch. |
| |
| elsif not Expander_Active then |
| Set_Analyzed (N, Full_Analysis); |
| |
| if Serious_Errors_Detected > 0 and then Scope_Is_Transient then |
| Scope_Stack.Table |
| (Scope_Stack.Last).Actions_To_Be_Wrapped := (others => No_List); |
| Pop_Scope; |
| end if; |
| |
| return; |
| |
| else |
| begin |
| Debug_A_Entry ("expanding ", N); |
| |
| -- Processing depends on node kind. For full details on the |
| -- expansion activity required in each case, see bodies of |
| -- corresponding expand routines. |
| |
| case Nkind (N) is |
| |
| when N_Abort_Statement => |
| Expand_N_Abort_Statement (N); |
| |
| when N_Accept_Statement => |
| Expand_N_Accept_Statement (N); |
| |
| when N_Aggregate => |
| Expand_N_Aggregate (N); |
| |
| when N_Allocator => |
| Expand_N_Allocator (N); |
| |
| when N_And_Then => |
| Expand_N_And_Then (N); |
| |
| when N_Assignment_Statement => |
| Expand_N_Assignment_Statement (N); |
| |
| when N_Asynchronous_Select => |
| Expand_N_Asynchronous_Select (N); |
| |
| when N_Attribute_Definition_Clause => |
| Expand_N_Attribute_Definition_Clause (N); |
| |
| when N_Attribute_Reference => |
| Expand_N_Attribute_Reference (N); |
| |
| when N_Block_Statement => |
| Expand_N_Block_Statement (N); |
| |
| when N_Case_Expression => |
| Expand_N_Case_Expression (N); |
| |
| when N_Case_Statement => |
| Expand_N_Case_Statement (N); |
| |
| when N_Conditional_Entry_Call => |
| Expand_N_Conditional_Entry_Call (N); |
| |
| when N_Delay_Relative_Statement => |
| Expand_N_Delay_Relative_Statement (N); |
| |
| when N_Delay_Until_Statement => |
| Expand_N_Delay_Until_Statement (N); |
| |
| when N_Entry_Body => |
| Expand_N_Entry_Body (N); |
| |
| when N_Entry_Call_Statement => |
| Expand_N_Entry_Call_Statement (N); |
| |
| when N_Entry_Declaration => |
| Expand_N_Entry_Declaration (N); |
| |
| when N_Exception_Declaration => |
| Expand_N_Exception_Declaration (N); |
| |
| when N_Exception_Renaming_Declaration => |
| Expand_N_Exception_Renaming_Declaration (N); |
| |
| when N_Exit_Statement => |
| Expand_N_Exit_Statement (N); |
| |
| when N_Expanded_Name => |
| Expand_N_Expanded_Name (N); |
| |
| when N_Explicit_Dereference => |
| Expand_N_Explicit_Dereference (N); |
| |
| when N_Expression_With_Actions => |
| Expand_N_Expression_With_Actions (N); |
| |
| when N_Extended_Return_Statement => |
| Expand_N_Extended_Return_Statement (N); |
| |
| when N_Extension_Aggregate => |
| Expand_N_Extension_Aggregate (N); |
| |
| when N_Free_Statement => |
| Expand_N_Free_Statement (N); |
| |
| when N_Freeze_Entity => |
| Expand_N_Freeze_Entity (N); |
| |
| when N_Full_Type_Declaration => |
| Expand_N_Full_Type_Declaration (N); |
| |
| when N_Function_Call => |
| Expand_N_Function_Call (N); |
| |
| when N_Generic_Instantiation => |
| Expand_N_Generic_Instantiation (N); |
| |
| when N_Goto_Statement => |
| Expand_N_Goto_Statement (N); |
| |
| when N_Handled_Sequence_Of_Statements => |
| Expand_N_Handled_Sequence_Of_Statements (N); |
| |
| when N_Identifier => |
| Expand_N_Identifier (N); |
| |
| when N_If_Expression => |
| Expand_N_If_Expression (N); |
| |
| when N_Indexed_Component => |
| Expand_N_Indexed_Component (N); |
| |
| when N_If_Statement => |
| Expand_N_If_Statement (N); |
| |
| when N_In => |
| Expand_N_In (N); |
| |
| when N_Loop_Statement => |
| Expand_N_Loop_Statement (N); |
| |
| when N_Not_In => |
| Expand_N_Not_In (N); |
| |
| when N_Null => |
| Expand_N_Null (N); |
| |
| when N_Object_Declaration => |
| Expand_N_Object_Declaration (N); |
| |
| when N_Object_Renaming_Declaration => |
| Expand_N_Object_Renaming_Declaration (N); |
| |
| when N_Op_Add => |
| Expand_N_Op_Add (N); |
| |
| when N_Op_Abs => |
| Expand_N_Op_Abs (N); |
| |
| when N_Op_And => |
| Expand_N_Op_And (N); |
| |
| when N_Op_Concat => |
| Expand_N_Op_Concat (N); |
| |
| when N_Op_Divide => |
| Expand_N_Op_Divide (N); |
| |
| when N_Op_Eq => |
| Expand_N_Op_Eq (N); |
| |
| when N_Op_Expon => |
| Expand_N_Op_Expon (N); |
| |
| when N_Op_Ge => |
| Expand_N_Op_Ge (N); |
| |
| when N_Op_Gt => |
| Expand_N_Op_Gt (N); |
| |
| when N_Op_Le => |
| Expand_N_Op_Le (N); |
| |
| when N_Op_Lt => |
| Expand_N_Op_Lt (N); |
| |
| when N_Op_Minus => |
| Expand_N_Op_Minus (N); |
| |
| when N_Op_Mod => |
| Expand_N_Op_Mod (N); |
| |
| when N_Op_Multiply => |
| Expand_N_Op_Multiply (N); |
| |
| when N_Op_Ne => |
| Expand_N_Op_Ne (N); |
| |
| when N_Op_Not => |
| Expand_N_Op_Not (N); |
| |
| when N_Op_Or => |
| Expand_N_Op_Or (N); |
| |
| when N_Op_Plus => |
| Expand_N_Op_Plus (N); |
| |
| when N_Op_Rem => |
| Expand_N_Op_Rem (N); |
| |
| when N_Op_Rotate_Left => |
| Expand_N_Op_Rotate_Left (N); |
| |
| when N_Op_Rotate_Right => |
| Expand_N_Op_Rotate_Right (N); |
| |
| when N_Op_Shift_Left => |
| Expand_N_Op_Shift_Left (N); |
| |
| when N_Op_Shift_Right => |
| Expand_N_Op_Shift_Right (N); |
| |
| when N_Op_Shift_Right_Arithmetic => |
| Expand_N_Op_Shift_Right_Arithmetic (N); |
| |
| when N_Op_Subtract => |
| Expand_N_Op_Subtract (N); |
| |
| when N_Op_Xor => |
| Expand_N_Op_Xor (N); |
| |
| when N_Or_Else => |
| Expand_N_Or_Else (N); |
| |
| when N_Package_Body => |
| Expand_N_Package_Body (N); |
| |
| when N_Package_Declaration => |
| Expand_N_Package_Declaration (N); |
| |
| when N_Package_Renaming_Declaration => |
| Expand_N_Package_Renaming_Declaration (N); |
| |
| when N_Subprogram_Renaming_Declaration => |
| Expand_N_Subprogram_Renaming_Declaration (N); |
| |
| when N_Pragma => |
| Expand_N_Pragma (N); |
| |
| when N_Procedure_Call_Statement => |
| Expand_N_Procedure_Call_Statement (N); |
| |
| when N_Protected_Type_Declaration => |
| Expand_N_Protected_Type_Declaration (N); |
| |
| when N_Protected_Body => |
| Expand_N_Protected_Body (N); |
| |
| when N_Qualified_Expression => |
| Expand_N_Qualified_Expression (N); |
| |
| when N_Quantified_Expression => |
| Expand_N_Quantified_Expression (N); |
| |
| when N_Raise_Statement => |
| Expand_N_Raise_Statement (N); |
| |
| when N_Raise_Constraint_Error => |
| Expand_N_Raise_Constraint_Error (N); |
| |
| when N_Raise_Expression => |
| Expand_N_Raise_Expression (N); |
| |
| when N_Raise_Program_Error => |
| Expand_N_Raise_Program_Error (N); |
| |
| when N_Raise_Storage_Error => |
| Expand_N_Raise_Storage_Error (N); |
| |
| when N_Real_Literal => |
| Expand_N_Real_Literal (N); |
| |
| when N_Record_Representation_Clause => |
| Expand_N_Record_Representation_Clause (N); |
| |
| when N_Requeue_Statement => |
| Expand_N_Requeue_Statement (N); |
| |
| when N_Simple_Return_Statement => |
| Expand_N_Simple_Return_Statement (N); |
| |
| when N_Selected_Component => |
| Expand_N_Selected_Component (N); |
| |
| when N_Selective_Accept => |
| Expand_N_Selective_Accept (N); |
| |
| when N_Single_Task_Declaration => |
| Expand_N_Single_Task_Declaration (N); |
| |
| when N_Slice => |
| Expand_N_Slice (N); |
| |
| when N_Subtype_Indication => |
| Expand_N_Subtype_Indication (N); |
| |
| when N_Subprogram_Body => |
| Expand_N_Subprogram_Body (N); |
| |
| when N_Subprogram_Body_Stub => |
| Expand_N_Subprogram_Body_Stub (N); |
| |
| when N_Subprogram_Declaration => |
| Expand_N_Subprogram_Declaration (N); |
| |
| when N_Task_Body => |
| Expand_N_Task_Body (N); |
| |
| when N_Task_Type_Declaration => |
| Expand_N_Task_Type_Declaration (N); |
| |
| when N_Timed_Entry_Call => |
| Expand_N_Timed_Entry_Call (N); |
| |
| when N_Type_Conversion => |
| Expand_N_Type_Conversion (N); |
| |
| when N_Unchecked_Expression => |
| Expand_N_Unchecked_Expression (N); |
| |
| when N_Unchecked_Type_Conversion => |
| Expand_N_Unchecked_Type_Conversion (N); |
| |
| when N_Variant_Part => |
| Expand_N_Variant_Part (N); |
| |
| -- For all other node kinds, no expansion activity required |
| |
| when others => |
| null; |
| |
| end case; |
| |
| exception |
| when RE_Not_Available => |
| return; |
| end; |
| |
| -- Set result as analyzed and then do a possible transient wrap. The |
| -- transient wrap must be done after the Analyzed flag is set on, so |
| -- that we do not get a recursive attempt to expand the node N. |
| |
| Set_Analyzed (N); |
| |
| -- Deal with transient scopes |
| |
| if Scope_Is_Transient and then N = Node_To_Be_Wrapped then |
| case Nkind (N) is |
| when N_Statement_Other_Than_Procedure_Call | |
| N_Procedure_Call_Statement => |
| Wrap_Transient_Statement (N); |
| |
| when N_Object_Declaration | |
| N_Object_Renaming_Declaration | |
| N_Subtype_Declaration => |
| Wrap_Transient_Declaration (N); |
| |
| when others => Wrap_Transient_Expression (N); |
| end case; |
| end if; |
| |
| Debug_A_Exit ("expanding ", N, " (done)"); |
| end if; |
| end Expand; |
| |
| --------------------------- |
| -- Expander_Mode_Restore -- |
| --------------------------- |
| |
| procedure Expander_Mode_Restore is |
| begin |
| -- Not active (has no effect) in ASIS and GNATprove modes (see comments |
| -- in spec of Expander_Mode_Save_And_Set). |
| |
| if ASIS_Mode or GNATprove_Mode then |
| return; |
| end if; |
| |
| -- Otherwise restore the flag |
| |
| Expander_Active := Expander_Flags.Table (Expander_Flags.Last); |
| Expander_Flags.Decrement_Last; |
| |
| -- Keep expander off if serious errors detected. In this case we do not |
| -- need expansion, and continued expansion may cause cascaded errors or |
| -- compiler bombs. |
| |
| if Serious_Errors_Detected /= 0 then |
| Expander_Active := False; |
| end if; |
| end Expander_Mode_Restore; |
| |
| -------------------------------- |
| -- Expander_Mode_Save_And_Set -- |
| -------------------------------- |
| |
| procedure Expander_Mode_Save_And_Set (Status : Boolean) is |
| begin |
| -- Not active (has no effect) in ASIS and GNATprove modes (see comments |
| -- in spec of Expander_Mode_Save_And_Set). |
| |
| if ASIS_Mode or GNATprove_Mode then |
| return; |
| end if; |
| |
| -- Otherwise save and set the flag |
| |
| Expander_Flags.Increment_Last; |
| Expander_Flags.Table (Expander_Flags.Last) := Expander_Active; |
| Expander_Active := Status; |
| end Expander_Mode_Save_And_Set; |
| |
| end Expander; |
