------------------------------------------------------------------------------
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------------------------------------------------------------------------------
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-- --
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-- --
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-- GNAT COMPILER COMPONENTS --
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-- GNAT COMPILER COMPONENTS --
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-- --
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-- --
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-- E X P _ C H 5 --
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-- E X P _ C H 5 --
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-- --
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-- --
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-- B o d y --
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-- B o d y --
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-- --
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-- --
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-- Copyright (C) 1992-2012, Free Software Foundation, Inc. --
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-- Copyright (C) 1992-2012, Free Software Foundation, Inc. --
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-- --
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-- --
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-- GNAT is free software; you can redistribute it and/or modify it under --
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-- GNAT is free software; you can redistribute it and/or modify it under --
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-- terms of the GNU General Public License as published by the Free Soft- --
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-- terms of the GNU General Public License as published by the Free Soft- --
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-- ware Foundation; either version 3, or (at your option) any later ver- --
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-- ware Foundation; either version 3, or (at your option) any later ver- --
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-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
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-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
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-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
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-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
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-- for more details. You should have received a copy of the GNU General --
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-- for more details. You should have received a copy of the GNU General --
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-- Public License distributed with GNAT; see file COPYING3. If not, go to --
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-- Public License distributed with GNAT; see file COPYING3. If not, go to --
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-- http://www.gnu.org/licenses for a complete copy of the license. --
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-- http://www.gnu.org/licenses for a complete copy of the license. --
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-- --
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-- --
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-- GNAT was originally developed by the GNAT team at New York University. --
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-- GNAT was originally developed by the GNAT team at New York University. --
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-- Extensive contributions were provided by Ada Core Technologies Inc. --
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-- Extensive contributions were provided by Ada Core Technologies Inc. --
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-- --
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-- --
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------------------------------------------------------------------------------
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------------------------------------------------------------------------------
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with Aspects; use Aspects;
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with Aspects; use Aspects;
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with Atree; use Atree;
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with Atree; use Atree;
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with Checks; use Checks;
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with Checks; use Checks;
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with Debug; use Debug;
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with Debug; use Debug;
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with Einfo; use Einfo;
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with Einfo; use Einfo;
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with Errout; use Errout;
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with Errout; use Errout;
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with Exp_Aggr; use Exp_Aggr;
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with Exp_Aggr; use Exp_Aggr;
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with Exp_Ch6; use Exp_Ch6;
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with Exp_Ch6; use Exp_Ch6;
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with Exp_Ch7; use Exp_Ch7;
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with Exp_Ch7; use Exp_Ch7;
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with Exp_Ch11; use Exp_Ch11;
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with Exp_Ch11; use Exp_Ch11;
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with Exp_Dbug; use Exp_Dbug;
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with Exp_Dbug; use Exp_Dbug;
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with Exp_Pakd; use Exp_Pakd;
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with Exp_Pakd; use Exp_Pakd;
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with Exp_Tss; use Exp_Tss;
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with Exp_Tss; use Exp_Tss;
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with Exp_Util; use Exp_Util;
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with Exp_Util; use Exp_Util;
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with Namet; use Namet;
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with Namet; use Namet;
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with Nlists; use Nlists;
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with Nlists; use Nlists;
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with Nmake; use Nmake;
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with Nmake; use Nmake;
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with Opt; use Opt;
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with Opt; use Opt;
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with Restrict; use Restrict;
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with Restrict; use Restrict;
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with Rident; use Rident;
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with Rident; use Rident;
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with Rtsfind; use Rtsfind;
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with Rtsfind; use Rtsfind;
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with Sinfo; use Sinfo;
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with Sinfo; use Sinfo;
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with Sem; use Sem;
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with Sem; use Sem;
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with Sem_Aux; use Sem_Aux;
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with Sem_Aux; use Sem_Aux;
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with Sem_Ch3; use Sem_Ch3;
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with Sem_Ch3; use Sem_Ch3;
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with Sem_Ch8; use Sem_Ch8;
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with Sem_Ch8; use Sem_Ch8;
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with Sem_Ch13; use Sem_Ch13;
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with Sem_Ch13; use Sem_Ch13;
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with Sem_Eval; use Sem_Eval;
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with Sem_Eval; use Sem_Eval;
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with Sem_Res; use Sem_Res;
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with Sem_Res; use Sem_Res;
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with Sem_Util; use Sem_Util;
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with Sem_Util; use Sem_Util;
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with Snames; use Snames;
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with Snames; use Snames;
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with Stand; use Stand;
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with Stand; use Stand;
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with Stringt; use Stringt;
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with Stringt; use Stringt;
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with Targparm; use Targparm;
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with Targparm; use Targparm;
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with Tbuild; use Tbuild;
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with Tbuild; use Tbuild;
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with Validsw; use Validsw;
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with Validsw; use Validsw;
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package body Exp_Ch5 is
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package body Exp_Ch5 is
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function Change_Of_Representation (N : Node_Id) return Boolean;
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function Change_Of_Representation (N : Node_Id) return Boolean;
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-- Determine if the right hand side of assignment N is a type conversion
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-- Determine if the right hand side of assignment N is a type conversion
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-- which requires a change of representation. Called only for the array
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-- which requires a change of representation. Called only for the array
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-- and record cases.
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-- and record cases.
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procedure Expand_Assign_Array (N : Node_Id; Rhs : Node_Id);
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procedure Expand_Assign_Array (N : Node_Id; Rhs : Node_Id);
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-- N is an assignment which assigns an array value. This routine process
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-- N is an assignment which assigns an array value. This routine process
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-- the various special cases and checks required for such assignments,
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-- the various special cases and checks required for such assignments,
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-- including change of representation. Rhs is normally simply the right
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-- including change of representation. Rhs is normally simply the right
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-- hand side of the assignment, except that if the right hand side is a
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-- hand side of the assignment, except that if the right hand side is a
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-- type conversion or a qualified expression, then the RHS is the actual
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-- type conversion or a qualified expression, then the RHS is the actual
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-- expression inside any such type conversions or qualifications.
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-- expression inside any such type conversions or qualifications.
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function Expand_Assign_Array_Loop
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function Expand_Assign_Array_Loop
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(N : Node_Id;
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(N : Node_Id;
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Larray : Entity_Id;
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Larray : Entity_Id;
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Rarray : Entity_Id;
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Rarray : Entity_Id;
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L_Type : Entity_Id;
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L_Type : Entity_Id;
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R_Type : Entity_Id;
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R_Type : Entity_Id;
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Ndim : Pos;
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Ndim : Pos;
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Rev : Boolean) return Node_Id;
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Rev : Boolean) return Node_Id;
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-- N is an assignment statement which assigns an array value. This routine
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-- N is an assignment statement which assigns an array value. This routine
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-- expands the assignment into a loop (or nested loops for the case of a
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-- expands the assignment into a loop (or nested loops for the case of a
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-- multi-dimensional array) to do the assignment component by component.
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-- multi-dimensional array) to do the assignment component by component.
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-- Larray and Rarray are the entities of the actual arrays on the left
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-- Larray and Rarray are the entities of the actual arrays on the left
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-- hand and right hand sides. L_Type and R_Type are the types of these
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-- hand and right hand sides. L_Type and R_Type are the types of these
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-- arrays (which may not be the same, due to either sliding, or to a
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-- arrays (which may not be the same, due to either sliding, or to a
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-- change of representation case). Ndim is the number of dimensions and
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-- change of representation case). Ndim is the number of dimensions and
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-- the parameter Rev indicates if the loops run normally (Rev = False),
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-- the parameter Rev indicates if the loops run normally (Rev = False),
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-- or reversed (Rev = True). The value returned is the constructed
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-- or reversed (Rev = True). The value returned is the constructed
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-- loop statement. Auxiliary declarations are inserted before node N
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-- loop statement. Auxiliary declarations are inserted before node N
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-- using the standard Insert_Actions mechanism.
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-- using the standard Insert_Actions mechanism.
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procedure Expand_Assign_Record (N : Node_Id);
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procedure Expand_Assign_Record (N : Node_Id);
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-- N is an assignment of a non-tagged record value. This routine handles
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-- N is an assignment of a non-tagged record value. This routine handles
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-- the case where the assignment must be made component by component,
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-- the case where the assignment must be made component by component,
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-- either because the target is not byte aligned, or there is a change
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-- either because the target is not byte aligned, or there is a change
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-- of representation, or when we have a tagged type with a representation
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-- of representation, or when we have a tagged type with a representation
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-- clause (this last case is required because holes in the tagged type
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-- clause (this last case is required because holes in the tagged type
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-- might be filled with components from child types).
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-- might be filled with components from child types).
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procedure Expand_Iterator_Loop (N : Node_Id);
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procedure Expand_Iterator_Loop (N : Node_Id);
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-- Expand loop over arrays and containers that uses the form "for X of C"
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-- Expand loop over arrays and containers that uses the form "for X of C"
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-- with an optional subtype mark, or "for Y in C".
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-- with an optional subtype mark, or "for Y in C".
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procedure Expand_Predicated_Loop (N : Node_Id);
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procedure Expand_Predicated_Loop (N : Node_Id);
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-- Expand for loop over predicated subtype
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-- Expand for loop over predicated subtype
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function Make_Tag_Ctrl_Assignment (N : Node_Id) return List_Id;
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function Make_Tag_Ctrl_Assignment (N : Node_Id) return List_Id;
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-- Generate the necessary code for controlled and tagged assignment, that
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-- Generate the necessary code for controlled and tagged assignment, that
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-- is to say, finalization of the target before, adjustment of the target
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-- is to say, finalization of the target before, adjustment of the target
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-- after and save and restore of the tag and finalization pointers which
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-- after and save and restore of the tag and finalization pointers which
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-- are not 'part of the value' and must not be changed upon assignment. N
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-- are not 'part of the value' and must not be changed upon assignment. N
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-- is the original Assignment node.
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-- is the original Assignment node.
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|
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------------------------------
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------------------------------
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-- Change_Of_Representation --
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-- Change_Of_Representation --
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------------------------------
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------------------------------
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function Change_Of_Representation (N : Node_Id) return Boolean is
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function Change_Of_Representation (N : Node_Id) return Boolean is
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Rhs : constant Node_Id := Expression (N);
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Rhs : constant Node_Id := Expression (N);
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begin
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begin
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return
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return
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Nkind (Rhs) = N_Type_Conversion
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Nkind (Rhs) = N_Type_Conversion
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and then
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and then
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not Same_Representation (Etype (Rhs), Etype (Expression (Rhs)));
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not Same_Representation (Etype (Rhs), Etype (Expression (Rhs)));
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end Change_Of_Representation;
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end Change_Of_Representation;
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-------------------------
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-------------------------
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-- Expand_Assign_Array --
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-- Expand_Assign_Array --
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-------------------------
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-------------------------
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-- There are two issues here. First, do we let Gigi do a block move, or
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-- There are two issues here. First, do we let Gigi do a block move, or
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-- do we expand out into a loop? Second, we need to set the two flags
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-- do we expand out into a loop? Second, we need to set the two flags
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-- Forwards_OK and Backwards_OK which show whether the block move (or
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-- Forwards_OK and Backwards_OK which show whether the block move (or
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-- corresponding loops) can be legitimately done in a forwards (low to
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-- corresponding loops) can be legitimately done in a forwards (low to
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-- high) or backwards (high to low) manner.
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-- high) or backwards (high to low) manner.
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procedure Expand_Assign_Array (N : Node_Id; Rhs : Node_Id) is
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procedure Expand_Assign_Array (N : Node_Id; Rhs : Node_Id) is
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Loc : constant Source_Ptr := Sloc (N);
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Loc : constant Source_Ptr := Sloc (N);
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Lhs : constant Node_Id := Name (N);
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Lhs : constant Node_Id := Name (N);
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Act_Lhs : constant Node_Id := Get_Referenced_Object (Lhs);
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Act_Lhs : constant Node_Id := Get_Referenced_Object (Lhs);
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Act_Rhs : Node_Id := Get_Referenced_Object (Rhs);
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Act_Rhs : Node_Id := Get_Referenced_Object (Rhs);
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L_Type : constant Entity_Id :=
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L_Type : constant Entity_Id :=
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Underlying_Type (Get_Actual_Subtype (Act_Lhs));
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Underlying_Type (Get_Actual_Subtype (Act_Lhs));
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R_Type : Entity_Id :=
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R_Type : Entity_Id :=
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Underlying_Type (Get_Actual_Subtype (Act_Rhs));
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Underlying_Type (Get_Actual_Subtype (Act_Rhs));
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L_Slice : constant Boolean := Nkind (Act_Lhs) = N_Slice;
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L_Slice : constant Boolean := Nkind (Act_Lhs) = N_Slice;
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R_Slice : constant Boolean := Nkind (Act_Rhs) = N_Slice;
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R_Slice : constant Boolean := Nkind (Act_Rhs) = N_Slice;
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Crep : constant Boolean := Change_Of_Representation (N);
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Crep : constant Boolean := Change_Of_Representation (N);
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Larray : Node_Id;
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Larray : Node_Id;
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Rarray : Node_Id;
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Rarray : Node_Id;
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Ndim : constant Pos := Number_Dimensions (L_Type);
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Ndim : constant Pos := Number_Dimensions (L_Type);
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Loop_Required : Boolean := False;
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Loop_Required : Boolean := False;
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-- This switch is set to True if the array move must be done using
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-- This switch is set to True if the array move must be done using
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-- an explicit front end generated loop.
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-- an explicit front end generated loop.
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procedure Apply_Dereference (Arg : Node_Id);
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procedure Apply_Dereference (Arg : Node_Id);
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-- If the argument is an access to an array, and the assignment is
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-- If the argument is an access to an array, and the assignment is
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-- converted into a procedure call, apply explicit dereference.
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-- converted into a procedure call, apply explicit dereference.
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function Has_Address_Clause (Exp : Node_Id) return Boolean;
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function Has_Address_Clause (Exp : Node_Id) return Boolean;
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-- Test if Exp is a reference to an array whose declaration has
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-- Test if Exp is a reference to an array whose declaration has
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-- an address clause, or it is a slice of such an array.
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-- an address clause, or it is a slice of such an array.
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function Is_Formal_Array (Exp : Node_Id) return Boolean;
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function Is_Formal_Array (Exp : Node_Id) return Boolean;
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-- Test if Exp is a reference to an array which is either a formal
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-- Test if Exp is a reference to an array which is either a formal
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-- parameter or a slice of a formal parameter. These are the cases
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-- parameter or a slice of a formal parameter. These are the cases
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-- where hidden aliasing can occur.
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-- where hidden aliasing can occur.
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function Is_Non_Local_Array (Exp : Node_Id) return Boolean;
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function Is_Non_Local_Array (Exp : Node_Id) return Boolean;
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-- Determine if Exp is a reference to an array variable which is other
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-- Determine if Exp is a reference to an array variable which is other
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-- than an object defined in the current scope, or a slice of such
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-- than an object defined in the current scope, or a slice of such
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-- an object. Such objects can be aliased to parameters (unlike local
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-- an object. Such objects can be aliased to parameters (unlike local
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-- array references).
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-- array references).
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-----------------------
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-----------------------
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-- Apply_Dereference --
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-- Apply_Dereference --
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-----------------------
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-----------------------
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procedure Apply_Dereference (Arg : Node_Id) is
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procedure Apply_Dereference (Arg : Node_Id) is
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Typ : constant Entity_Id := Etype (Arg);
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Typ : constant Entity_Id := Etype (Arg);
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begin
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begin
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if Is_Access_Type (Typ) then
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if Is_Access_Type (Typ) then
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Rewrite (Arg, Make_Explicit_Dereference (Loc,
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Rewrite (Arg, Make_Explicit_Dereference (Loc,
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Prefix => Relocate_Node (Arg)));
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Prefix => Relocate_Node (Arg)));
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Analyze_And_Resolve (Arg, Designated_Type (Typ));
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Analyze_And_Resolve (Arg, Designated_Type (Typ));
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end if;
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end if;
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end Apply_Dereference;
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end Apply_Dereference;
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------------------------
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------------------------
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-- Has_Address_Clause --
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-- Has_Address_Clause --
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------------------------
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------------------------
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function Has_Address_Clause (Exp : Node_Id) return Boolean is
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function Has_Address_Clause (Exp : Node_Id) return Boolean is
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begin
|
begin
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return
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return
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(Is_Entity_Name (Exp) and then
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(Is_Entity_Name (Exp) and then
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Present (Address_Clause (Entity (Exp))))
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Present (Address_Clause (Entity (Exp))))
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or else
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or else
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(Nkind (Exp) = N_Slice and then Has_Address_Clause (Prefix (Exp)));
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(Nkind (Exp) = N_Slice and then Has_Address_Clause (Prefix (Exp)));
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end Has_Address_Clause;
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end Has_Address_Clause;
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---------------------
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---------------------
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-- Is_Formal_Array --
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-- Is_Formal_Array --
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---------------------
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---------------------
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function Is_Formal_Array (Exp : Node_Id) return Boolean is
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function Is_Formal_Array (Exp : Node_Id) return Boolean is
|
begin
|
begin
|
return
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return
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(Is_Entity_Name (Exp) and then Is_Formal (Entity (Exp)))
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(Is_Entity_Name (Exp) and then Is_Formal (Entity (Exp)))
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or else
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or else
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(Nkind (Exp) = N_Slice and then Is_Formal_Array (Prefix (Exp)));
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(Nkind (Exp) = N_Slice and then Is_Formal_Array (Prefix (Exp)));
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end Is_Formal_Array;
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end Is_Formal_Array;
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------------------------
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------------------------
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-- Is_Non_Local_Array --
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-- Is_Non_Local_Array --
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------------------------
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------------------------
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|
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function Is_Non_Local_Array (Exp : Node_Id) return Boolean is
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function Is_Non_Local_Array (Exp : Node_Id) return Boolean is
|
begin
|
begin
|
return (Is_Entity_Name (Exp)
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return (Is_Entity_Name (Exp)
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and then Scope (Entity (Exp)) /= Current_Scope)
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and then Scope (Entity (Exp)) /= Current_Scope)
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or else (Nkind (Exp) = N_Slice
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or else (Nkind (Exp) = N_Slice
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and then Is_Non_Local_Array (Prefix (Exp)));
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and then Is_Non_Local_Array (Prefix (Exp)));
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end Is_Non_Local_Array;
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end Is_Non_Local_Array;
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-- Determine if Lhs, Rhs are formal arrays or nonlocal arrays
|
-- Determine if Lhs, Rhs are formal arrays or nonlocal arrays
|
|
|
Lhs_Formal : constant Boolean := Is_Formal_Array (Act_Lhs);
|
Lhs_Formal : constant Boolean := Is_Formal_Array (Act_Lhs);
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Rhs_Formal : constant Boolean := Is_Formal_Array (Act_Rhs);
|
Rhs_Formal : constant Boolean := Is_Formal_Array (Act_Rhs);
|
|
|
Lhs_Non_Local_Var : constant Boolean := Is_Non_Local_Array (Act_Lhs);
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Lhs_Non_Local_Var : constant Boolean := Is_Non_Local_Array (Act_Lhs);
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Rhs_Non_Local_Var : constant Boolean := Is_Non_Local_Array (Act_Rhs);
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Rhs_Non_Local_Var : constant Boolean := Is_Non_Local_Array (Act_Rhs);
|
|
|
-- Start of processing for Expand_Assign_Array
|
-- Start of processing for Expand_Assign_Array
|
|
|
begin
|
begin
|
-- Deal with length check. Note that the length check is done with
|
-- Deal with length check. Note that the length check is done with
|
-- respect to the right hand side as given, not a possible underlying
|
-- respect to the right hand side as given, not a possible underlying
|
-- renamed object, since this would generate incorrect extra checks.
|
-- renamed object, since this would generate incorrect extra checks.
|
|
|
Apply_Length_Check (Rhs, L_Type);
|
Apply_Length_Check (Rhs, L_Type);
|
|
|
-- We start by assuming that the move can be done in either direction,
|
-- We start by assuming that the move can be done in either direction,
|
-- i.e. that the two sides are completely disjoint.
|
-- i.e. that the two sides are completely disjoint.
|
|
|
Set_Forwards_OK (N, True);
|
Set_Forwards_OK (N, True);
|
Set_Backwards_OK (N, True);
|
Set_Backwards_OK (N, True);
|
|
|
-- Normally it is only the slice case that can lead to overlap, and
|
-- Normally it is only the slice case that can lead to overlap, and
|
-- explicit checks for slices are made below. But there is one case
|
-- explicit checks for slices are made below. But there is one case
|
-- where the slice can be implicit and invisible to us: when we have a
|
-- where the slice can be implicit and invisible to us: when we have a
|
-- one dimensional array, and either both operands are parameters, or
|
-- one dimensional array, and either both operands are parameters, or
|
-- one is a parameter (which can be a slice passed by reference) and the
|
-- one is a parameter (which can be a slice passed by reference) and the
|
-- other is a non-local variable. In this case the parameter could be a
|
-- other is a non-local variable. In this case the parameter could be a
|
-- slice that overlaps with the other operand.
|
-- slice that overlaps with the other operand.
|
|
|
-- However, if the array subtype is a constrained first subtype in the
|
-- However, if the array subtype is a constrained first subtype in the
|
-- parameter case, then we don't have to worry about overlap, since
|
-- parameter case, then we don't have to worry about overlap, since
|
-- slice assignments aren't possible (other than for a slice denoting
|
-- slice assignments aren't possible (other than for a slice denoting
|
-- the whole array).
|
-- the whole array).
|
|
|
-- Note: No overlap is possible if there is a change of representation,
|
-- Note: No overlap is possible if there is a change of representation,
|
-- so we can exclude this case.
|
-- so we can exclude this case.
|
|
|
if Ndim = 1
|
if Ndim = 1
|
and then not Crep
|
and then not Crep
|
and then
|
and then
|
((Lhs_Formal and Rhs_Formal)
|
((Lhs_Formal and Rhs_Formal)
|
or else
|
or else
|
(Lhs_Formal and Rhs_Non_Local_Var)
|
(Lhs_Formal and Rhs_Non_Local_Var)
|
or else
|
or else
|
(Rhs_Formal and Lhs_Non_Local_Var))
|
(Rhs_Formal and Lhs_Non_Local_Var))
|
and then
|
and then
|
(not Is_Constrained (Etype (Lhs))
|
(not Is_Constrained (Etype (Lhs))
|
or else not Is_First_Subtype (Etype (Lhs)))
|
or else not Is_First_Subtype (Etype (Lhs)))
|
|
|
-- In the case of compiling for the Java or .NET Virtual Machine,
|
-- In the case of compiling for the Java or .NET Virtual Machine,
|
-- slices are always passed by making a copy, so we don't have to
|
-- slices are always passed by making a copy, so we don't have to
|
-- worry about overlap. We also want to prevent generation of "<"
|
-- worry about overlap. We also want to prevent generation of "<"
|
-- comparisons for array addresses, since that's a meaningless
|
-- comparisons for array addresses, since that's a meaningless
|
-- operation on the VM.
|
-- operation on the VM.
|
|
|
and then VM_Target = No_VM
|
and then VM_Target = No_VM
|
then
|
then
|
Set_Forwards_OK (N, False);
|
Set_Forwards_OK (N, False);
|
Set_Backwards_OK (N, False);
|
Set_Backwards_OK (N, False);
|
|
|
-- Note: the bit-packed case is not worrisome here, since if we have
|
-- Note: the bit-packed case is not worrisome here, since if we have
|
-- a slice passed as a parameter, it is always aligned on a byte
|
-- a slice passed as a parameter, it is always aligned on a byte
|
-- boundary, and if there are no explicit slices, the assignment
|
-- boundary, and if there are no explicit slices, the assignment
|
-- can be performed directly.
|
-- can be performed directly.
|
end if;
|
end if;
|
|
|
-- If either operand has an address clause clear Backwards_OK and
|
-- If either operand has an address clause clear Backwards_OK and
|
-- Forwards_OK, since we cannot tell if the operands overlap. We
|
-- Forwards_OK, since we cannot tell if the operands overlap. We
|
-- exclude this treatment when Rhs is an aggregate, since we know
|
-- exclude this treatment when Rhs is an aggregate, since we know
|
-- that overlap can't occur.
|
-- that overlap can't occur.
|
|
|
if (Has_Address_Clause (Lhs) and then Nkind (Rhs) /= N_Aggregate)
|
if (Has_Address_Clause (Lhs) and then Nkind (Rhs) /= N_Aggregate)
|
or else Has_Address_Clause (Rhs)
|
or else Has_Address_Clause (Rhs)
|
then
|
then
|
Set_Forwards_OK (N, False);
|
Set_Forwards_OK (N, False);
|
Set_Backwards_OK (N, False);
|
Set_Backwards_OK (N, False);
|
end if;
|
end if;
|
|
|
-- We certainly must use a loop for change of representation and also
|
-- We certainly must use a loop for change of representation and also
|
-- we use the operand of the conversion on the right hand side as the
|
-- we use the operand of the conversion on the right hand side as the
|
-- effective right hand side (the component types must match in this
|
-- effective right hand side (the component types must match in this
|
-- situation).
|
-- situation).
|
|
|
if Crep then
|
if Crep then
|
Act_Rhs := Get_Referenced_Object (Rhs);
|
Act_Rhs := Get_Referenced_Object (Rhs);
|
R_Type := Get_Actual_Subtype (Act_Rhs);
|
R_Type := Get_Actual_Subtype (Act_Rhs);
|
Loop_Required := True;
|
Loop_Required := True;
|
|
|
-- We require a loop if the left side is possibly bit unaligned
|
-- We require a loop if the left side is possibly bit unaligned
|
|
|
elsif Possible_Bit_Aligned_Component (Lhs)
|
elsif Possible_Bit_Aligned_Component (Lhs)
|
or else
|
or else
|
Possible_Bit_Aligned_Component (Rhs)
|
Possible_Bit_Aligned_Component (Rhs)
|
then
|
then
|
Loop_Required := True;
|
Loop_Required := True;
|
|
|
-- Arrays with controlled components are expanded into a loop to force
|
-- Arrays with controlled components are expanded into a loop to force
|
-- calls to Adjust at the component level.
|
-- calls to Adjust at the component level.
|
|
|
elsif Has_Controlled_Component (L_Type) then
|
elsif Has_Controlled_Component (L_Type) then
|
Loop_Required := True;
|
Loop_Required := True;
|
|
|
-- If object is atomic, we cannot tolerate a loop
|
-- If object is atomic, we cannot tolerate a loop
|
|
|
elsif Is_Atomic_Object (Act_Lhs)
|
elsif Is_Atomic_Object (Act_Lhs)
|
or else
|
or else
|
Is_Atomic_Object (Act_Rhs)
|
Is_Atomic_Object (Act_Rhs)
|
then
|
then
|
return;
|
return;
|
|
|
-- Loop is required if we have atomic components since we have to
|
-- Loop is required if we have atomic components since we have to
|
-- be sure to do any accesses on an element by element basis.
|
-- be sure to do any accesses on an element by element basis.
|
|
|
elsif Has_Atomic_Components (L_Type)
|
elsif Has_Atomic_Components (L_Type)
|
or else Has_Atomic_Components (R_Type)
|
or else Has_Atomic_Components (R_Type)
|
or else Is_Atomic (Component_Type (L_Type))
|
or else Is_Atomic (Component_Type (L_Type))
|
or else Is_Atomic (Component_Type (R_Type))
|
or else Is_Atomic (Component_Type (R_Type))
|
then
|
then
|
Loop_Required := True;
|
Loop_Required := True;
|
|
|
-- Case where no slice is involved
|
-- Case where no slice is involved
|
|
|
elsif not L_Slice and not R_Slice then
|
elsif not L_Slice and not R_Slice then
|
|
|
-- The following code deals with the case of unconstrained bit packed
|
-- The following code deals with the case of unconstrained bit packed
|
-- arrays. The problem is that the template for such arrays contains
|
-- arrays. The problem is that the template for such arrays contains
|
-- the bounds of the actual source level array, but the copy of an
|
-- the bounds of the actual source level array, but the copy of an
|
-- entire array requires the bounds of the underlying array. It would
|
-- entire array requires the bounds of the underlying array. It would
|
-- be nice if the back end could take care of this, but right now it
|
-- be nice if the back end could take care of this, but right now it
|
-- does not know how, so if we have such a type, then we expand out
|
-- does not know how, so if we have such a type, then we expand out
|
-- into a loop, which is inefficient but works correctly. If we don't
|
-- into a loop, which is inefficient but works correctly. If we don't
|
-- do this, we get the wrong length computed for the array to be
|
-- do this, we get the wrong length computed for the array to be
|
-- moved. The two cases we need to worry about are:
|
-- moved. The two cases we need to worry about are:
|
|
|
-- Explicit dereference of an unconstrained packed array type as in
|
-- Explicit dereference of an unconstrained packed array type as in
|
-- the following example:
|
-- the following example:
|
|
|
-- procedure C52 is
|
-- procedure C52 is
|
-- type BITS is array(INTEGER range <>) of BOOLEAN;
|
-- type BITS is array(INTEGER range <>) of BOOLEAN;
|
-- pragma PACK(BITS);
|
-- pragma PACK(BITS);
|
-- type A is access BITS;
|
-- type A is access BITS;
|
-- P1,P2 : A;
|
-- P1,P2 : A;
|
-- begin
|
-- begin
|
-- P1 := new BITS (1 .. 65_535);
|
-- P1 := new BITS (1 .. 65_535);
|
-- P2 := new BITS (1 .. 65_535);
|
-- P2 := new BITS (1 .. 65_535);
|
-- P2.ALL := P1.ALL;
|
-- P2.ALL := P1.ALL;
|
-- end C52;
|
-- end C52;
|
|
|
-- A formal parameter reference with an unconstrained bit array type
|
-- A formal parameter reference with an unconstrained bit array type
|
-- is the other case we need to worry about (here we assume the same
|
-- is the other case we need to worry about (here we assume the same
|
-- BITS type declared above):
|
-- BITS type declared above):
|
|
|
-- procedure Write_All (File : out BITS; Contents : BITS);
|
-- procedure Write_All (File : out BITS; Contents : BITS);
|
-- begin
|
-- begin
|
-- File.Storage := Contents;
|
-- File.Storage := Contents;
|
-- end Write_All;
|
-- end Write_All;
|
|
|
-- We expand to a loop in either of these two cases
|
-- We expand to a loop in either of these two cases
|
|
|
-- Question for future thought. Another potentially more efficient
|
-- Question for future thought. Another potentially more efficient
|
-- approach would be to create the actual subtype, and then do an
|
-- approach would be to create the actual subtype, and then do an
|
-- unchecked conversion to this actual subtype ???
|
-- unchecked conversion to this actual subtype ???
|
|
|
Check_Unconstrained_Bit_Packed_Array : declare
|
Check_Unconstrained_Bit_Packed_Array : declare
|
|
|
function Is_UBPA_Reference (Opnd : Node_Id) return Boolean;
|
function Is_UBPA_Reference (Opnd : Node_Id) return Boolean;
|
-- Function to perform required test for the first case, above
|
-- Function to perform required test for the first case, above
|
-- (dereference of an unconstrained bit packed array).
|
-- (dereference of an unconstrained bit packed array).
|
|
|
-----------------------
|
-----------------------
|
-- Is_UBPA_Reference --
|
-- Is_UBPA_Reference --
|
-----------------------
|
-----------------------
|
|
|
function Is_UBPA_Reference (Opnd : Node_Id) return Boolean is
|
function Is_UBPA_Reference (Opnd : Node_Id) return Boolean is
|
Typ : constant Entity_Id := Underlying_Type (Etype (Opnd));
|
Typ : constant Entity_Id := Underlying_Type (Etype (Opnd));
|
P_Type : Entity_Id;
|
P_Type : Entity_Id;
|
Des_Type : Entity_Id;
|
Des_Type : Entity_Id;
|
|
|
begin
|
begin
|
if Present (Packed_Array_Type (Typ))
|
if Present (Packed_Array_Type (Typ))
|
and then Is_Array_Type (Packed_Array_Type (Typ))
|
and then Is_Array_Type (Packed_Array_Type (Typ))
|
and then not Is_Constrained (Packed_Array_Type (Typ))
|
and then not Is_Constrained (Packed_Array_Type (Typ))
|
then
|
then
|
return True;
|
return True;
|
|
|
elsif Nkind (Opnd) = N_Explicit_Dereference then
|
elsif Nkind (Opnd) = N_Explicit_Dereference then
|
P_Type := Underlying_Type (Etype (Prefix (Opnd)));
|
P_Type := Underlying_Type (Etype (Prefix (Opnd)));
|
|
|
if not Is_Access_Type (P_Type) then
|
if not Is_Access_Type (P_Type) then
|
return False;
|
return False;
|
|
|
else
|
else
|
Des_Type := Designated_Type (P_Type);
|
Des_Type := Designated_Type (P_Type);
|
return
|
return
|
Is_Bit_Packed_Array (Des_Type)
|
Is_Bit_Packed_Array (Des_Type)
|
and then not Is_Constrained (Des_Type);
|
and then not Is_Constrained (Des_Type);
|
end if;
|
end if;
|
|
|
else
|
else
|
return False;
|
return False;
|
end if;
|
end if;
|
end Is_UBPA_Reference;
|
end Is_UBPA_Reference;
|
|
|
-- Start of processing for Check_Unconstrained_Bit_Packed_Array
|
-- Start of processing for Check_Unconstrained_Bit_Packed_Array
|
|
|
begin
|
begin
|
if Is_UBPA_Reference (Lhs)
|
if Is_UBPA_Reference (Lhs)
|
or else
|
or else
|
Is_UBPA_Reference (Rhs)
|
Is_UBPA_Reference (Rhs)
|
then
|
then
|
Loop_Required := True;
|
Loop_Required := True;
|
|
|
-- Here if we do not have the case of a reference to a bit packed
|
-- Here if we do not have the case of a reference to a bit packed
|
-- unconstrained array case. In this case gigi can most certainly
|
-- unconstrained array case. In this case gigi can most certainly
|
-- handle the assignment if a forwards move is allowed.
|
-- handle the assignment if a forwards move is allowed.
|
|
|
-- (could it handle the backwards case also???)
|
-- (could it handle the backwards case also???)
|
|
|
elsif Forwards_OK (N) then
|
elsif Forwards_OK (N) then
|
return;
|
return;
|
end if;
|
end if;
|
end Check_Unconstrained_Bit_Packed_Array;
|
end Check_Unconstrained_Bit_Packed_Array;
|
|
|
-- The back end can always handle the assignment if the right side is a
|
-- The back end can always handle the assignment if the right side is a
|
-- string literal (note that overlap is definitely impossible in this
|
-- string literal (note that overlap is definitely impossible in this
|
-- case). If the type is packed, a string literal is always converted
|
-- case). If the type is packed, a string literal is always converted
|
-- into an aggregate, except in the case of a null slice, for which no
|
-- into an aggregate, except in the case of a null slice, for which no
|
-- aggregate can be written. In that case, rewrite the assignment as a
|
-- aggregate can be written. In that case, rewrite the assignment as a
|
-- null statement, a length check has already been emitted to verify
|
-- null statement, a length check has already been emitted to verify
|
-- that the range of the left-hand side is empty.
|
-- that the range of the left-hand side is empty.
|
|
|
-- Note that this code is not executed if we have an assignment of a
|
-- Note that this code is not executed if we have an assignment of a
|
-- string literal to a non-bit aligned component of a record, a case
|
-- string literal to a non-bit aligned component of a record, a case
|
-- which cannot be handled by the backend.
|
-- which cannot be handled by the backend.
|
|
|
elsif Nkind (Rhs) = N_String_Literal then
|
elsif Nkind (Rhs) = N_String_Literal then
|
if String_Length (Strval (Rhs)) = 0
|
if String_Length (Strval (Rhs)) = 0
|
and then Is_Bit_Packed_Array (L_Type)
|
and then Is_Bit_Packed_Array (L_Type)
|
then
|
then
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
Analyze (N);
|
Analyze (N);
|
end if;
|
end if;
|
|
|
return;
|
return;
|
|
|
-- If either operand is bit packed, then we need a loop, since we can't
|
-- If either operand is bit packed, then we need a loop, since we can't
|
-- be sure that the slice is byte aligned. Similarly, if either operand
|
-- be sure that the slice is byte aligned. Similarly, if either operand
|
-- is a possibly unaligned slice, then we need a loop (since the back
|
-- is a possibly unaligned slice, then we need a loop (since the back
|
-- end cannot handle unaligned slices).
|
-- end cannot handle unaligned slices).
|
|
|
elsif Is_Bit_Packed_Array (L_Type)
|
elsif Is_Bit_Packed_Array (L_Type)
|
or else Is_Bit_Packed_Array (R_Type)
|
or else Is_Bit_Packed_Array (R_Type)
|
or else Is_Possibly_Unaligned_Slice (Lhs)
|
or else Is_Possibly_Unaligned_Slice (Lhs)
|
or else Is_Possibly_Unaligned_Slice (Rhs)
|
or else Is_Possibly_Unaligned_Slice (Rhs)
|
then
|
then
|
Loop_Required := True;
|
Loop_Required := True;
|
|
|
-- If we are not bit-packed, and we have only one slice, then no overlap
|
-- If we are not bit-packed, and we have only one slice, then no overlap
|
-- is possible except in the parameter case, so we can let the back end
|
-- is possible except in the parameter case, so we can let the back end
|
-- handle things.
|
-- handle things.
|
|
|
elsif not (L_Slice and R_Slice) then
|
elsif not (L_Slice and R_Slice) then
|
if Forwards_OK (N) then
|
if Forwards_OK (N) then
|
return;
|
return;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- If the right-hand side is a string literal, introduce a temporary for
|
-- If the right-hand side is a string literal, introduce a temporary for
|
-- it, for use in the generated loop that will follow.
|
-- it, for use in the generated loop that will follow.
|
|
|
if Nkind (Rhs) = N_String_Literal then
|
if Nkind (Rhs) = N_String_Literal then
|
declare
|
declare
|
Temp : constant Entity_Id := Make_Temporary (Loc, 'T', Rhs);
|
Temp : constant Entity_Id := Make_Temporary (Loc, 'T', Rhs);
|
Decl : Node_Id;
|
Decl : Node_Id;
|
|
|
begin
|
begin
|
Decl :=
|
Decl :=
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Temp,
|
Defining_Identifier => Temp,
|
Object_Definition => New_Occurrence_Of (L_Type, Loc),
|
Object_Definition => New_Occurrence_Of (L_Type, Loc),
|
Expression => Relocate_Node (Rhs));
|
Expression => Relocate_Node (Rhs));
|
|
|
Insert_Action (N, Decl);
|
Insert_Action (N, Decl);
|
Rewrite (Rhs, New_Occurrence_Of (Temp, Loc));
|
Rewrite (Rhs, New_Occurrence_Of (Temp, Loc));
|
R_Type := Etype (Temp);
|
R_Type := Etype (Temp);
|
end;
|
end;
|
end if;
|
end if;
|
|
|
-- Come here to complete the analysis
|
-- Come here to complete the analysis
|
|
|
-- Loop_Required: Set to True if we know that a loop is required
|
-- Loop_Required: Set to True if we know that a loop is required
|
-- regardless of overlap considerations.
|
-- regardless of overlap considerations.
|
|
|
-- Forwards_OK: Set to False if we already know that a forwards
|
-- Forwards_OK: Set to False if we already know that a forwards
|
-- move is not safe, else set to True.
|
-- move is not safe, else set to True.
|
|
|
-- Backwards_OK: Set to False if we already know that a backwards
|
-- Backwards_OK: Set to False if we already know that a backwards
|
-- move is not safe, else set to True
|
-- move is not safe, else set to True
|
|
|
-- Our task at this stage is to complete the overlap analysis, which can
|
-- Our task at this stage is to complete the overlap analysis, which can
|
-- result in possibly setting Forwards_OK or Backwards_OK to False, and
|
-- result in possibly setting Forwards_OK or Backwards_OK to False, and
|
-- then generating the final code, either by deciding that it is OK
|
-- then generating the final code, either by deciding that it is OK
|
-- after all to let Gigi handle it, or by generating appropriate code
|
-- after all to let Gigi handle it, or by generating appropriate code
|
-- in the front end.
|
-- in the front end.
|
|
|
declare
|
declare
|
L_Index_Typ : constant Node_Id := Etype (First_Index (L_Type));
|
L_Index_Typ : constant Node_Id := Etype (First_Index (L_Type));
|
R_Index_Typ : constant Node_Id := Etype (First_Index (R_Type));
|
R_Index_Typ : constant Node_Id := Etype (First_Index (R_Type));
|
|
|
Left_Lo : constant Node_Id := Type_Low_Bound (L_Index_Typ);
|
Left_Lo : constant Node_Id := Type_Low_Bound (L_Index_Typ);
|
Left_Hi : constant Node_Id := Type_High_Bound (L_Index_Typ);
|
Left_Hi : constant Node_Id := Type_High_Bound (L_Index_Typ);
|
Right_Lo : constant Node_Id := Type_Low_Bound (R_Index_Typ);
|
Right_Lo : constant Node_Id := Type_Low_Bound (R_Index_Typ);
|
Right_Hi : constant Node_Id := Type_High_Bound (R_Index_Typ);
|
Right_Hi : constant Node_Id := Type_High_Bound (R_Index_Typ);
|
|
|
Act_L_Array : Node_Id;
|
Act_L_Array : Node_Id;
|
Act_R_Array : Node_Id;
|
Act_R_Array : Node_Id;
|
|
|
Cleft_Lo : Node_Id;
|
Cleft_Lo : Node_Id;
|
Cright_Lo : Node_Id;
|
Cright_Lo : Node_Id;
|
Condition : Node_Id;
|
Condition : Node_Id;
|
|
|
Cresult : Compare_Result;
|
Cresult : Compare_Result;
|
|
|
begin
|
begin
|
-- Get the expressions for the arrays. If we are dealing with a
|
-- Get the expressions for the arrays. If we are dealing with a
|
-- private type, then convert to the underlying type. We can do
|
-- private type, then convert to the underlying type. We can do
|
-- direct assignments to an array that is a private type, but we
|
-- direct assignments to an array that is a private type, but we
|
-- cannot assign to elements of the array without this extra
|
-- cannot assign to elements of the array without this extra
|
-- unchecked conversion.
|
-- unchecked conversion.
|
|
|
-- Note: We propagate Parent to the conversion nodes to generate
|
-- Note: We propagate Parent to the conversion nodes to generate
|
-- a well-formed subtree.
|
-- a well-formed subtree.
|
|
|
if Nkind (Act_Lhs) = N_Slice then
|
if Nkind (Act_Lhs) = N_Slice then
|
Larray := Prefix (Act_Lhs);
|
Larray := Prefix (Act_Lhs);
|
else
|
else
|
Larray := Act_Lhs;
|
Larray := Act_Lhs;
|
|
|
if Is_Private_Type (Etype (Larray)) then
|
if Is_Private_Type (Etype (Larray)) then
|
declare
|
declare
|
Par : constant Node_Id := Parent (Larray);
|
Par : constant Node_Id := Parent (Larray);
|
begin
|
begin
|
Larray :=
|
Larray :=
|
Unchecked_Convert_To
|
Unchecked_Convert_To
|
(Underlying_Type (Etype (Larray)), Larray);
|
(Underlying_Type (Etype (Larray)), Larray);
|
Set_Parent (Larray, Par);
|
Set_Parent (Larray, Par);
|
end;
|
end;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
if Nkind (Act_Rhs) = N_Slice then
|
if Nkind (Act_Rhs) = N_Slice then
|
Rarray := Prefix (Act_Rhs);
|
Rarray := Prefix (Act_Rhs);
|
else
|
else
|
Rarray := Act_Rhs;
|
Rarray := Act_Rhs;
|
|
|
if Is_Private_Type (Etype (Rarray)) then
|
if Is_Private_Type (Etype (Rarray)) then
|
declare
|
declare
|
Par : constant Node_Id := Parent (Rarray);
|
Par : constant Node_Id := Parent (Rarray);
|
begin
|
begin
|
Rarray :=
|
Rarray :=
|
Unchecked_Convert_To
|
Unchecked_Convert_To
|
(Underlying_Type (Etype (Rarray)), Rarray);
|
(Underlying_Type (Etype (Rarray)), Rarray);
|
Set_Parent (Rarray, Par);
|
Set_Parent (Rarray, Par);
|
end;
|
end;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- If both sides are slices, we must figure out whether it is safe
|
-- If both sides are slices, we must figure out whether it is safe
|
-- to do the move in one direction or the other. It is always safe
|
-- to do the move in one direction or the other. It is always safe
|
-- if there is a change of representation since obviously two arrays
|
-- if there is a change of representation since obviously two arrays
|
-- with different representations cannot possibly overlap.
|
-- with different representations cannot possibly overlap.
|
|
|
if (not Crep) and L_Slice and R_Slice then
|
if (not Crep) and L_Slice and R_Slice then
|
Act_L_Array := Get_Referenced_Object (Prefix (Act_Lhs));
|
Act_L_Array := Get_Referenced_Object (Prefix (Act_Lhs));
|
Act_R_Array := Get_Referenced_Object (Prefix (Act_Rhs));
|
Act_R_Array := Get_Referenced_Object (Prefix (Act_Rhs));
|
|
|
-- If both left and right hand arrays are entity names, and refer
|
-- If both left and right hand arrays are entity names, and refer
|
-- to different entities, then we know that the move is safe (the
|
-- to different entities, then we know that the move is safe (the
|
-- two storage areas are completely disjoint).
|
-- two storage areas are completely disjoint).
|
|
|
if Is_Entity_Name (Act_L_Array)
|
if Is_Entity_Name (Act_L_Array)
|
and then Is_Entity_Name (Act_R_Array)
|
and then Is_Entity_Name (Act_R_Array)
|
and then Entity (Act_L_Array) /= Entity (Act_R_Array)
|
and then Entity (Act_L_Array) /= Entity (Act_R_Array)
|
then
|
then
|
null;
|
null;
|
|
|
-- Otherwise, we assume the worst, which is that the two arrays
|
-- Otherwise, we assume the worst, which is that the two arrays
|
-- are the same array. There is no need to check if we know that
|
-- are the same array. There is no need to check if we know that
|
-- is the case, because if we don't know it, we still have to
|
-- is the case, because if we don't know it, we still have to
|
-- assume it!
|
-- assume it!
|
|
|
-- Generally if the same array is involved, then we have an
|
-- Generally if the same array is involved, then we have an
|
-- overlapping case. We will have to really assume the worst (i.e.
|
-- overlapping case. We will have to really assume the worst (i.e.
|
-- set neither of the OK flags) unless we can determine the lower
|
-- set neither of the OK flags) unless we can determine the lower
|
-- or upper bounds at compile time and compare them.
|
-- or upper bounds at compile time and compare them.
|
|
|
else
|
else
|
Cresult :=
|
Cresult :=
|
Compile_Time_Compare
|
Compile_Time_Compare
|
(Left_Lo, Right_Lo, Assume_Valid => True);
|
(Left_Lo, Right_Lo, Assume_Valid => True);
|
|
|
if Cresult = Unknown then
|
if Cresult = Unknown then
|
Cresult :=
|
Cresult :=
|
Compile_Time_Compare
|
Compile_Time_Compare
|
(Left_Hi, Right_Hi, Assume_Valid => True);
|
(Left_Hi, Right_Hi, Assume_Valid => True);
|
end if;
|
end if;
|
|
|
case Cresult is
|
case Cresult is
|
when LT | LE | EQ => Set_Backwards_OK (N, False);
|
when LT | LE | EQ => Set_Backwards_OK (N, False);
|
when GT | GE => Set_Forwards_OK (N, False);
|
when GT | GE => Set_Forwards_OK (N, False);
|
when NE | Unknown => Set_Backwards_OK (N, False);
|
when NE | Unknown => Set_Backwards_OK (N, False);
|
Set_Forwards_OK (N, False);
|
Set_Forwards_OK (N, False);
|
end case;
|
end case;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- If after that analysis Loop_Required is False, meaning that we
|
-- If after that analysis Loop_Required is False, meaning that we
|
-- have not discovered some non-overlap reason for requiring a loop,
|
-- have not discovered some non-overlap reason for requiring a loop,
|
-- then the outcome depends on the capabilities of the back end.
|
-- then the outcome depends on the capabilities of the back end.
|
|
|
if not Loop_Required then
|
if not Loop_Required then
|
|
|
-- The GCC back end can deal with all cases of overlap by falling
|
-- The GCC back end can deal with all cases of overlap by falling
|
-- back to memmove if it cannot use a more efficient approach.
|
-- back to memmove if it cannot use a more efficient approach.
|
|
|
if VM_Target = No_VM and not AAMP_On_Target then
|
if VM_Target = No_VM and not AAMP_On_Target then
|
return;
|
return;
|
|
|
-- Assume other back ends can handle it if Forwards_OK is set
|
-- Assume other back ends can handle it if Forwards_OK is set
|
|
|
elsif Forwards_OK (N) then
|
elsif Forwards_OK (N) then
|
return;
|
return;
|
|
|
-- If Forwards_OK is not set, the back end will need something
|
-- If Forwards_OK is not set, the back end will need something
|
-- like memmove to handle the move. For now, this processing is
|
-- like memmove to handle the move. For now, this processing is
|
-- activated using the .s debug flag (-gnatd.s).
|
-- activated using the .s debug flag (-gnatd.s).
|
|
|
elsif Debug_Flag_Dot_S then
|
elsif Debug_Flag_Dot_S then
|
return;
|
return;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- At this stage we have to generate an explicit loop, and we have
|
-- At this stage we have to generate an explicit loop, and we have
|
-- the following cases:
|
-- the following cases:
|
|
|
-- Forwards_OK = True
|
-- Forwards_OK = True
|
|
|
-- Rnn : right_index := right_index'First;
|
-- Rnn : right_index := right_index'First;
|
-- for Lnn in left-index loop
|
-- for Lnn in left-index loop
|
-- left (Lnn) := right (Rnn);
|
-- left (Lnn) := right (Rnn);
|
-- Rnn := right_index'Succ (Rnn);
|
-- Rnn := right_index'Succ (Rnn);
|
-- end loop;
|
-- end loop;
|
|
|
-- Note: the above code MUST be analyzed with checks off, because
|
-- Note: the above code MUST be analyzed with checks off, because
|
-- otherwise the Succ could overflow. But in any case this is more
|
-- otherwise the Succ could overflow. But in any case this is more
|
-- efficient!
|
-- efficient!
|
|
|
-- Forwards_OK = False, Backwards_OK = True
|
-- Forwards_OK = False, Backwards_OK = True
|
|
|
-- Rnn : right_index := right_index'Last;
|
-- Rnn : right_index := right_index'Last;
|
-- for Lnn in reverse left-index loop
|
-- for Lnn in reverse left-index loop
|
-- left (Lnn) := right (Rnn);
|
-- left (Lnn) := right (Rnn);
|
-- Rnn := right_index'Pred (Rnn);
|
-- Rnn := right_index'Pred (Rnn);
|
-- end loop;
|
-- end loop;
|
|
|
-- Note: the above code MUST be analyzed with checks off, because
|
-- Note: the above code MUST be analyzed with checks off, because
|
-- otherwise the Pred could overflow. But in any case this is more
|
-- otherwise the Pred could overflow. But in any case this is more
|
-- efficient!
|
-- efficient!
|
|
|
-- Forwards_OK = Backwards_OK = False
|
-- Forwards_OK = Backwards_OK = False
|
|
|
-- This only happens if we have the same array on each side. It is
|
-- This only happens if we have the same array on each side. It is
|
-- possible to create situations using overlays that violate this,
|
-- possible to create situations using overlays that violate this,
|
-- but we simply do not promise to get this "right" in this case.
|
-- but we simply do not promise to get this "right" in this case.
|
|
|
-- There are two possible subcases. If the No_Implicit_Conditionals
|
-- There are two possible subcases. If the No_Implicit_Conditionals
|
-- restriction is set, then we generate the following code:
|
-- restriction is set, then we generate the following code:
|
|
|
-- declare
|
-- declare
|
-- T : constant <operand-type> := rhs;
|
-- T : constant <operand-type> := rhs;
|
-- begin
|
-- begin
|
-- lhs := T;
|
-- lhs := T;
|
-- end;
|
-- end;
|
|
|
-- If implicit conditionals are permitted, then we generate:
|
-- If implicit conditionals are permitted, then we generate:
|
|
|
-- if Left_Lo <= Right_Lo then
|
-- if Left_Lo <= Right_Lo then
|
-- <code for Forwards_OK = True above>
|
-- <code for Forwards_OK = True above>
|
-- else
|
-- else
|
-- <code for Backwards_OK = True above>
|
-- <code for Backwards_OK = True above>
|
-- end if;
|
-- end if;
|
|
|
-- In order to detect possible aliasing, we examine the renamed
|
-- In order to detect possible aliasing, we examine the renamed
|
-- expression when the source or target is a renaming. However,
|
-- expression when the source or target is a renaming. However,
|
-- the renaming may be intended to capture an address that may be
|
-- the renaming may be intended to capture an address that may be
|
-- affected by subsequent code, and therefore we must recover
|
-- affected by subsequent code, and therefore we must recover
|
-- the actual entity for the expansion that follows, not the
|
-- the actual entity for the expansion that follows, not the
|
-- object it renames. In particular, if source or target designate
|
-- object it renames. In particular, if source or target designate
|
-- a portion of a dynamically allocated object, the pointer to it
|
-- a portion of a dynamically allocated object, the pointer to it
|
-- may be reassigned but the renaming preserves the proper location.
|
-- may be reassigned but the renaming preserves the proper location.
|
|
|
if Is_Entity_Name (Rhs)
|
if Is_Entity_Name (Rhs)
|
and then
|
and then
|
Nkind (Parent (Entity (Rhs))) = N_Object_Renaming_Declaration
|
Nkind (Parent (Entity (Rhs))) = N_Object_Renaming_Declaration
|
and then Nkind (Act_Rhs) = N_Slice
|
and then Nkind (Act_Rhs) = N_Slice
|
then
|
then
|
Rarray := Rhs;
|
Rarray := Rhs;
|
end if;
|
end if;
|
|
|
if Is_Entity_Name (Lhs)
|
if Is_Entity_Name (Lhs)
|
and then
|
and then
|
Nkind (Parent (Entity (Lhs))) = N_Object_Renaming_Declaration
|
Nkind (Parent (Entity (Lhs))) = N_Object_Renaming_Declaration
|
and then Nkind (Act_Lhs) = N_Slice
|
and then Nkind (Act_Lhs) = N_Slice
|
then
|
then
|
Larray := Lhs;
|
Larray := Lhs;
|
end if;
|
end if;
|
|
|
-- Cases where either Forwards_OK or Backwards_OK is true
|
-- Cases where either Forwards_OK or Backwards_OK is true
|
|
|
if Forwards_OK (N) or else Backwards_OK (N) then
|
if Forwards_OK (N) or else Backwards_OK (N) then
|
if Needs_Finalization (Component_Type (L_Type))
|
if Needs_Finalization (Component_Type (L_Type))
|
and then Base_Type (L_Type) = Base_Type (R_Type)
|
and then Base_Type (L_Type) = Base_Type (R_Type)
|
and then Ndim = 1
|
and then Ndim = 1
|
and then not No_Ctrl_Actions (N)
|
and then not No_Ctrl_Actions (N)
|
then
|
then
|
declare
|
declare
|
Proc : constant Entity_Id :=
|
Proc : constant Entity_Id :=
|
TSS (Base_Type (L_Type), TSS_Slice_Assign);
|
TSS (Base_Type (L_Type), TSS_Slice_Assign);
|
Actuals : List_Id;
|
Actuals : List_Id;
|
|
|
begin
|
begin
|
Apply_Dereference (Larray);
|
Apply_Dereference (Larray);
|
Apply_Dereference (Rarray);
|
Apply_Dereference (Rarray);
|
Actuals := New_List (
|
Actuals := New_List (
|
Duplicate_Subexpr (Larray, Name_Req => True),
|
Duplicate_Subexpr (Larray, Name_Req => True),
|
Duplicate_Subexpr (Rarray, Name_Req => True),
|
Duplicate_Subexpr (Rarray, Name_Req => True),
|
Duplicate_Subexpr (Left_Lo, Name_Req => True),
|
Duplicate_Subexpr (Left_Lo, Name_Req => True),
|
Duplicate_Subexpr (Left_Hi, Name_Req => True),
|
Duplicate_Subexpr (Left_Hi, Name_Req => True),
|
Duplicate_Subexpr (Right_Lo, Name_Req => True),
|
Duplicate_Subexpr (Right_Lo, Name_Req => True),
|
Duplicate_Subexpr (Right_Hi, Name_Req => True));
|
Duplicate_Subexpr (Right_Hi, Name_Req => True));
|
|
|
Append_To (Actuals,
|
Append_To (Actuals,
|
New_Occurrence_Of (
|
New_Occurrence_Of (
|
Boolean_Literals (not Forwards_OK (N)), Loc));
|
Boolean_Literals (not Forwards_OK (N)), Loc));
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_Procedure_Call_Statement (Loc,
|
Make_Procedure_Call_Statement (Loc,
|
Name => New_Reference_To (Proc, Loc),
|
Name => New_Reference_To (Proc, Loc),
|
Parameter_Associations => Actuals));
|
Parameter_Associations => Actuals));
|
end;
|
end;
|
|
|
else
|
else
|
Rewrite (N,
|
Rewrite (N,
|
Expand_Assign_Array_Loop
|
Expand_Assign_Array_Loop
|
(N, Larray, Rarray, L_Type, R_Type, Ndim,
|
(N, Larray, Rarray, L_Type, R_Type, Ndim,
|
Rev => not Forwards_OK (N)));
|
Rev => not Forwards_OK (N)));
|
end if;
|
end if;
|
|
|
-- Case of both are false with No_Implicit_Conditionals
|
-- Case of both are false with No_Implicit_Conditionals
|
|
|
elsif Restriction_Active (No_Implicit_Conditionals) then
|
elsif Restriction_Active (No_Implicit_Conditionals) then
|
declare
|
declare
|
T : constant Entity_Id :=
|
T : constant Entity_Id :=
|
Make_Defining_Identifier (Loc, Chars => Name_T);
|
Make_Defining_Identifier (Loc, Chars => Name_T);
|
|
|
begin
|
begin
|
Rewrite (N,
|
Rewrite (N,
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Declarations => New_List (
|
Declarations => New_List (
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => T,
|
Defining_Identifier => T,
|
Constant_Present => True,
|
Constant_Present => True,
|
Object_Definition =>
|
Object_Definition =>
|
New_Occurrence_Of (Etype (Rhs), Loc),
|
New_Occurrence_Of (Etype (Rhs), Loc),
|
Expression => Relocate_Node (Rhs))),
|
Expression => Relocate_Node (Rhs))),
|
|
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Statements => New_List (
|
Statements => New_List (
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => Relocate_Node (Lhs),
|
Name => Relocate_Node (Lhs),
|
Expression => New_Occurrence_Of (T, Loc))))));
|
Expression => New_Occurrence_Of (T, Loc))))));
|
end;
|
end;
|
|
|
-- Case of both are false with implicit conditionals allowed
|
-- Case of both are false with implicit conditionals allowed
|
|
|
else
|
else
|
-- Before we generate this code, we must ensure that the left and
|
-- Before we generate this code, we must ensure that the left and
|
-- right side array types are defined. They may be itypes, and we
|
-- right side array types are defined. They may be itypes, and we
|
-- cannot let them be defined inside the if, since the first use
|
-- cannot let them be defined inside the if, since the first use
|
-- in the then may not be executed.
|
-- in the then may not be executed.
|
|
|
Ensure_Defined (L_Type, N);
|
Ensure_Defined (L_Type, N);
|
Ensure_Defined (R_Type, N);
|
Ensure_Defined (R_Type, N);
|
|
|
-- We normally compare addresses to find out which way round to
|
-- We normally compare addresses to find out which way round to
|
-- do the loop, since this is reliable, and handles the cases of
|
-- do the loop, since this is reliable, and handles the cases of
|
-- parameters, conversions etc. But we can't do that in the bit
|
-- parameters, conversions etc. But we can't do that in the bit
|
-- packed case or the VM case, because addresses don't work there.
|
-- packed case or the VM case, because addresses don't work there.
|
|
|
if not Is_Bit_Packed_Array (L_Type) and then VM_Target = No_VM then
|
if not Is_Bit_Packed_Array (L_Type) and then VM_Target = No_VM then
|
Condition :=
|
Condition :=
|
Make_Op_Le (Loc,
|
Make_Op_Le (Loc,
|
Left_Opnd =>
|
Left_Opnd =>
|
Unchecked_Convert_To (RTE (RE_Integer_Address),
|
Unchecked_Convert_To (RTE (RE_Integer_Address),
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix =>
|
Prefix =>
|
Duplicate_Subexpr_Move_Checks (Larray, True),
|
Duplicate_Subexpr_Move_Checks (Larray, True),
|
Expressions => New_List (
|
Expressions => New_List (
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
New_Reference_To
|
New_Reference_To
|
(L_Index_Typ, Loc),
|
(L_Index_Typ, Loc),
|
Attribute_Name => Name_First))),
|
Attribute_Name => Name_First))),
|
Attribute_Name => Name_Address)),
|
Attribute_Name => Name_Address)),
|
|
|
Right_Opnd =>
|
Right_Opnd =>
|
Unchecked_Convert_To (RTE (RE_Integer_Address),
|
Unchecked_Convert_To (RTE (RE_Integer_Address),
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix =>
|
Prefix =>
|
Duplicate_Subexpr_Move_Checks (Rarray, True),
|
Duplicate_Subexpr_Move_Checks (Rarray, True),
|
Expressions => New_List (
|
Expressions => New_List (
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
New_Reference_To
|
New_Reference_To
|
(R_Index_Typ, Loc),
|
(R_Index_Typ, Loc),
|
Attribute_Name => Name_First))),
|
Attribute_Name => Name_First))),
|
Attribute_Name => Name_Address)));
|
Attribute_Name => Name_Address)));
|
|
|
-- For the bit packed and VM cases we use the bounds. That's OK,
|
-- For the bit packed and VM cases we use the bounds. That's OK,
|
-- because we don't have to worry about parameters, since they
|
-- because we don't have to worry about parameters, since they
|
-- cannot cause overlap. Perhaps we should worry about weird slice
|
-- cannot cause overlap. Perhaps we should worry about weird slice
|
-- conversions ???
|
-- conversions ???
|
|
|
else
|
else
|
-- Copy the bounds
|
-- Copy the bounds
|
|
|
Cleft_Lo := New_Copy_Tree (Left_Lo);
|
Cleft_Lo := New_Copy_Tree (Left_Lo);
|
Cright_Lo := New_Copy_Tree (Right_Lo);
|
Cright_Lo := New_Copy_Tree (Right_Lo);
|
|
|
-- If the types do not match we add an implicit conversion
|
-- If the types do not match we add an implicit conversion
|
-- here to ensure proper match
|
-- here to ensure proper match
|
|
|
if Etype (Left_Lo) /= Etype (Right_Lo) then
|
if Etype (Left_Lo) /= Etype (Right_Lo) then
|
Cright_Lo :=
|
Cright_Lo :=
|
Unchecked_Convert_To (Etype (Left_Lo), Cright_Lo);
|
Unchecked_Convert_To (Etype (Left_Lo), Cright_Lo);
|
end if;
|
end if;
|
|
|
-- Reset the Analyzed flag, because the bounds of the index
|
-- Reset the Analyzed flag, because the bounds of the index
|
-- type itself may be universal, and must must be reanalyzed
|
-- type itself may be universal, and must must be reanalyzed
|
-- to acquire the proper type for the back end.
|
-- to acquire the proper type for the back end.
|
|
|
Set_Analyzed (Cleft_Lo, False);
|
Set_Analyzed (Cleft_Lo, False);
|
Set_Analyzed (Cright_Lo, False);
|
Set_Analyzed (Cright_Lo, False);
|
|
|
Condition :=
|
Condition :=
|
Make_Op_Le (Loc,
|
Make_Op_Le (Loc,
|
Left_Opnd => Cleft_Lo,
|
Left_Opnd => Cleft_Lo,
|
Right_Opnd => Cright_Lo);
|
Right_Opnd => Cright_Lo);
|
end if;
|
end if;
|
|
|
if Needs_Finalization (Component_Type (L_Type))
|
if Needs_Finalization (Component_Type (L_Type))
|
and then Base_Type (L_Type) = Base_Type (R_Type)
|
and then Base_Type (L_Type) = Base_Type (R_Type)
|
and then Ndim = 1
|
and then Ndim = 1
|
and then not No_Ctrl_Actions (N)
|
and then not No_Ctrl_Actions (N)
|
then
|
then
|
|
|
-- Call TSS procedure for array assignment, passing the
|
-- Call TSS procedure for array assignment, passing the
|
-- explicit bounds of right and left hand sides.
|
-- explicit bounds of right and left hand sides.
|
|
|
declare
|
declare
|
Proc : constant Entity_Id :=
|
Proc : constant Entity_Id :=
|
TSS (Base_Type (L_Type), TSS_Slice_Assign);
|
TSS (Base_Type (L_Type), TSS_Slice_Assign);
|
Actuals : List_Id;
|
Actuals : List_Id;
|
|
|
begin
|
begin
|
Apply_Dereference (Larray);
|
Apply_Dereference (Larray);
|
Apply_Dereference (Rarray);
|
Apply_Dereference (Rarray);
|
Actuals := New_List (
|
Actuals := New_List (
|
Duplicate_Subexpr (Larray, Name_Req => True),
|
Duplicate_Subexpr (Larray, Name_Req => True),
|
Duplicate_Subexpr (Rarray, Name_Req => True),
|
Duplicate_Subexpr (Rarray, Name_Req => True),
|
Duplicate_Subexpr (Left_Lo, Name_Req => True),
|
Duplicate_Subexpr (Left_Lo, Name_Req => True),
|
Duplicate_Subexpr (Left_Hi, Name_Req => True),
|
Duplicate_Subexpr (Left_Hi, Name_Req => True),
|
Duplicate_Subexpr (Right_Lo, Name_Req => True),
|
Duplicate_Subexpr (Right_Lo, Name_Req => True),
|
Duplicate_Subexpr (Right_Hi, Name_Req => True));
|
Duplicate_Subexpr (Right_Hi, Name_Req => True));
|
|
|
Append_To (Actuals,
|
Append_To (Actuals,
|
Make_Op_Not (Loc,
|
Make_Op_Not (Loc,
|
Right_Opnd => Condition));
|
Right_Opnd => Condition));
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_Procedure_Call_Statement (Loc,
|
Make_Procedure_Call_Statement (Loc,
|
Name => New_Reference_To (Proc, Loc),
|
Name => New_Reference_To (Proc, Loc),
|
Parameter_Associations => Actuals));
|
Parameter_Associations => Actuals));
|
end;
|
end;
|
|
|
else
|
else
|
Rewrite (N,
|
Rewrite (N,
|
Make_Implicit_If_Statement (N,
|
Make_Implicit_If_Statement (N,
|
Condition => Condition,
|
Condition => Condition,
|
|
|
Then_Statements => New_List (
|
Then_Statements => New_List (
|
Expand_Assign_Array_Loop
|
Expand_Assign_Array_Loop
|
(N, Larray, Rarray, L_Type, R_Type, Ndim,
|
(N, Larray, Rarray, L_Type, R_Type, Ndim,
|
Rev => False)),
|
Rev => False)),
|
|
|
Else_Statements => New_List (
|
Else_Statements => New_List (
|
Expand_Assign_Array_Loop
|
Expand_Assign_Array_Loop
|
(N, Larray, Rarray, L_Type, R_Type, Ndim,
|
(N, Larray, Rarray, L_Type, R_Type, Ndim,
|
Rev => True))));
|
Rev => True))));
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
Analyze (N, Suppress => All_Checks);
|
Analyze (N, Suppress => All_Checks);
|
end;
|
end;
|
|
|
exception
|
exception
|
when RE_Not_Available =>
|
when RE_Not_Available =>
|
return;
|
return;
|
end Expand_Assign_Array;
|
end Expand_Assign_Array;
|
|
|
------------------------------
|
------------------------------
|
-- Expand_Assign_Array_Loop --
|
-- Expand_Assign_Array_Loop --
|
------------------------------
|
------------------------------
|
|
|
-- The following is an example of the loop generated for the case of a
|
-- The following is an example of the loop generated for the case of a
|
-- two-dimensional array:
|
-- two-dimensional array:
|
|
|
-- declare
|
-- declare
|
-- R2b : Tm1X1 := 1;
|
-- R2b : Tm1X1 := 1;
|
-- begin
|
-- begin
|
-- for L1b in 1 .. 100 loop
|
-- for L1b in 1 .. 100 loop
|
-- declare
|
-- declare
|
-- R4b : Tm1X2 := 1;
|
-- R4b : Tm1X2 := 1;
|
-- begin
|
-- begin
|
-- for L3b in 1 .. 100 loop
|
-- for L3b in 1 .. 100 loop
|
-- vm1 (L1b, L3b) := vm2 (R2b, R4b);
|
-- vm1 (L1b, L3b) := vm2 (R2b, R4b);
|
-- R4b := Tm1X2'succ(R4b);
|
-- R4b := Tm1X2'succ(R4b);
|
-- end loop;
|
-- end loop;
|
-- end;
|
-- end;
|
-- R2b := Tm1X1'succ(R2b);
|
-- R2b := Tm1X1'succ(R2b);
|
-- end loop;
|
-- end loop;
|
-- end;
|
-- end;
|
|
|
-- Here Rev is False, and Tm1Xn are the subscript types for the right hand
|
-- Here Rev is False, and Tm1Xn are the subscript types for the right hand
|
-- side. The declarations of R2b and R4b are inserted before the original
|
-- side. The declarations of R2b and R4b are inserted before the original
|
-- assignment statement.
|
-- assignment statement.
|
|
|
function Expand_Assign_Array_Loop
|
function Expand_Assign_Array_Loop
|
(N : Node_Id;
|
(N : Node_Id;
|
Larray : Entity_Id;
|
Larray : Entity_Id;
|
Rarray : Entity_Id;
|
Rarray : Entity_Id;
|
L_Type : Entity_Id;
|
L_Type : Entity_Id;
|
R_Type : Entity_Id;
|
R_Type : Entity_Id;
|
Ndim : Pos;
|
Ndim : Pos;
|
Rev : Boolean) return Node_Id
|
Rev : Boolean) return Node_Id
|
is
|
is
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
|
|
Lnn : array (1 .. Ndim) of Entity_Id;
|
Lnn : array (1 .. Ndim) of Entity_Id;
|
Rnn : array (1 .. Ndim) of Entity_Id;
|
Rnn : array (1 .. Ndim) of Entity_Id;
|
-- Entities used as subscripts on left and right sides
|
-- Entities used as subscripts on left and right sides
|
|
|
L_Index_Type : array (1 .. Ndim) of Entity_Id;
|
L_Index_Type : array (1 .. Ndim) of Entity_Id;
|
R_Index_Type : array (1 .. Ndim) of Entity_Id;
|
R_Index_Type : array (1 .. Ndim) of Entity_Id;
|
-- Left and right index types
|
-- Left and right index types
|
|
|
Assign : Node_Id;
|
Assign : Node_Id;
|
|
|
F_Or_L : Name_Id;
|
F_Or_L : Name_Id;
|
S_Or_P : Name_Id;
|
S_Or_P : Name_Id;
|
|
|
function Build_Step (J : Nat) return Node_Id;
|
function Build_Step (J : Nat) return Node_Id;
|
-- The increment step for the index of the right-hand side is written
|
-- The increment step for the index of the right-hand side is written
|
-- as an attribute reference (Succ or Pred). This function returns
|
-- as an attribute reference (Succ or Pred). This function returns
|
-- the corresponding node, which is placed at the end of the loop body.
|
-- the corresponding node, which is placed at the end of the loop body.
|
|
|
----------------
|
----------------
|
-- Build_Step --
|
-- Build_Step --
|
----------------
|
----------------
|
|
|
function Build_Step (J : Nat) return Node_Id is
|
function Build_Step (J : Nat) return Node_Id is
|
Step : Node_Id;
|
Step : Node_Id;
|
Lim : Name_Id;
|
Lim : Name_Id;
|
|
|
begin
|
begin
|
if Rev then
|
if Rev then
|
Lim := Name_First;
|
Lim := Name_First;
|
else
|
else
|
Lim := Name_Last;
|
Lim := Name_Last;
|
end if;
|
end if;
|
|
|
Step :=
|
Step :=
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => New_Occurrence_Of (Rnn (J), Loc),
|
Name => New_Occurrence_Of (Rnn (J), Loc),
|
Expression =>
|
Expression =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
New_Occurrence_Of (R_Index_Type (J), Loc),
|
New_Occurrence_Of (R_Index_Type (J), Loc),
|
Attribute_Name => S_Or_P,
|
Attribute_Name => S_Or_P,
|
Expressions => New_List (
|
Expressions => New_List (
|
New_Occurrence_Of (Rnn (J), Loc))));
|
New_Occurrence_Of (Rnn (J), Loc))));
|
|
|
-- Note that on the last iteration of the loop, the index is increased
|
-- Note that on the last iteration of the loop, the index is increased
|
-- (or decreased) past the corresponding bound. This is consistent with
|
-- (or decreased) past the corresponding bound. This is consistent with
|
-- the C semantics of the back-end, where such an off-by-one value on a
|
-- the C semantics of the back-end, where such an off-by-one value on a
|
-- dead index variable is OK. However, in CodePeer mode this leads to
|
-- dead index variable is OK. However, in CodePeer mode this leads to
|
-- spurious warnings, and thus we place a guard around the attribute
|
-- spurious warnings, and thus we place a guard around the attribute
|
-- reference. For obvious reasons we only do this for CodePeer.
|
-- reference. For obvious reasons we only do this for CodePeer.
|
|
|
if CodePeer_Mode then
|
if CodePeer_Mode then
|
Step :=
|
Step :=
|
Make_If_Statement (Loc,
|
Make_If_Statement (Loc,
|
Condition =>
|
Condition =>
|
Make_Op_Ne (Loc,
|
Make_Op_Ne (Loc,
|
Left_Opnd => New_Occurrence_Of (Lnn (J), Loc),
|
Left_Opnd => New_Occurrence_Of (Lnn (J), Loc),
|
Right_Opnd =>
|
Right_Opnd =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix => New_Occurrence_Of (L_Index_Type (J), Loc),
|
Prefix => New_Occurrence_Of (L_Index_Type (J), Loc),
|
Attribute_Name => Lim)),
|
Attribute_Name => Lim)),
|
Then_Statements => New_List (Step));
|
Then_Statements => New_List (Step));
|
end if;
|
end if;
|
|
|
return Step;
|
return Step;
|
end Build_Step;
|
end Build_Step;
|
|
|
-- Start of processing for Expand_Assign_Array_Loop
|
-- Start of processing for Expand_Assign_Array_Loop
|
|
|
begin
|
begin
|
if Rev then
|
if Rev then
|
F_Or_L := Name_Last;
|
F_Or_L := Name_Last;
|
S_Or_P := Name_Pred;
|
S_Or_P := Name_Pred;
|
else
|
else
|
F_Or_L := Name_First;
|
F_Or_L := Name_First;
|
S_Or_P := Name_Succ;
|
S_Or_P := Name_Succ;
|
end if;
|
end if;
|
|
|
-- Setup index types and subscript entities
|
-- Setup index types and subscript entities
|
|
|
declare
|
declare
|
L_Index : Node_Id;
|
L_Index : Node_Id;
|
R_Index : Node_Id;
|
R_Index : Node_Id;
|
|
|
begin
|
begin
|
L_Index := First_Index (L_Type);
|
L_Index := First_Index (L_Type);
|
R_Index := First_Index (R_Type);
|
R_Index := First_Index (R_Type);
|
|
|
for J in 1 .. Ndim loop
|
for J in 1 .. Ndim loop
|
Lnn (J) := Make_Temporary (Loc, 'L');
|
Lnn (J) := Make_Temporary (Loc, 'L');
|
Rnn (J) := Make_Temporary (Loc, 'R');
|
Rnn (J) := Make_Temporary (Loc, 'R');
|
|
|
L_Index_Type (J) := Etype (L_Index);
|
L_Index_Type (J) := Etype (L_Index);
|
R_Index_Type (J) := Etype (R_Index);
|
R_Index_Type (J) := Etype (R_Index);
|
|
|
Next_Index (L_Index);
|
Next_Index (L_Index);
|
Next_Index (R_Index);
|
Next_Index (R_Index);
|
end loop;
|
end loop;
|
end;
|
end;
|
|
|
-- Now construct the assignment statement
|
-- Now construct the assignment statement
|
|
|
declare
|
declare
|
ExprL : constant List_Id := New_List;
|
ExprL : constant List_Id := New_List;
|
ExprR : constant List_Id := New_List;
|
ExprR : constant List_Id := New_List;
|
|
|
begin
|
begin
|
for J in 1 .. Ndim loop
|
for J in 1 .. Ndim loop
|
Append_To (ExprL, New_Occurrence_Of (Lnn (J), Loc));
|
Append_To (ExprL, New_Occurrence_Of (Lnn (J), Loc));
|
Append_To (ExprR, New_Occurrence_Of (Rnn (J), Loc));
|
Append_To (ExprR, New_Occurrence_Of (Rnn (J), Loc));
|
end loop;
|
end loop;
|
|
|
Assign :=
|
Assign :=
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name =>
|
Name =>
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix => Duplicate_Subexpr (Larray, Name_Req => True),
|
Prefix => Duplicate_Subexpr (Larray, Name_Req => True),
|
Expressions => ExprL),
|
Expressions => ExprL),
|
Expression =>
|
Expression =>
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix => Duplicate_Subexpr (Rarray, Name_Req => True),
|
Prefix => Duplicate_Subexpr (Rarray, Name_Req => True),
|
Expressions => ExprR));
|
Expressions => ExprR));
|
|
|
-- We set assignment OK, since there are some cases, e.g. in object
|
-- We set assignment OK, since there are some cases, e.g. in object
|
-- declarations, where we are actually assigning into a constant.
|
-- declarations, where we are actually assigning into a constant.
|
-- If there really is an illegality, it was caught long before now,
|
-- If there really is an illegality, it was caught long before now,
|
-- and was flagged when the original assignment was analyzed.
|
-- and was flagged when the original assignment was analyzed.
|
|
|
Set_Assignment_OK (Name (Assign));
|
Set_Assignment_OK (Name (Assign));
|
|
|
-- Propagate the No_Ctrl_Actions flag to individual assignments
|
-- Propagate the No_Ctrl_Actions flag to individual assignments
|
|
|
Set_No_Ctrl_Actions (Assign, No_Ctrl_Actions (N));
|
Set_No_Ctrl_Actions (Assign, No_Ctrl_Actions (N));
|
end;
|
end;
|
|
|
-- Now construct the loop from the inside out, with the last subscript
|
-- Now construct the loop from the inside out, with the last subscript
|
-- varying most rapidly. Note that Assign is first the raw assignment
|
-- varying most rapidly. Note that Assign is first the raw assignment
|
-- statement, and then subsequently the loop that wraps it up.
|
-- statement, and then subsequently the loop that wraps it up.
|
|
|
for J in reverse 1 .. Ndim loop
|
for J in reverse 1 .. Ndim loop
|
Assign :=
|
Assign :=
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Declarations => New_List (
|
Declarations => New_List (
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Rnn (J),
|
Defining_Identifier => Rnn (J),
|
Object_Definition =>
|
Object_Definition =>
|
New_Occurrence_Of (R_Index_Type (J), Loc),
|
New_Occurrence_Of (R_Index_Type (J), Loc),
|
Expression =>
|
Expression =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix => New_Occurrence_Of (R_Index_Type (J), Loc),
|
Prefix => New_Occurrence_Of (R_Index_Type (J), Loc),
|
Attribute_Name => F_Or_L))),
|
Attribute_Name => F_Or_L))),
|
|
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Statements => New_List (
|
Statements => New_List (
|
Make_Implicit_Loop_Statement (N,
|
Make_Implicit_Loop_Statement (N,
|
Iteration_Scheme =>
|
Iteration_Scheme =>
|
Make_Iteration_Scheme (Loc,
|
Make_Iteration_Scheme (Loc,
|
Loop_Parameter_Specification =>
|
Loop_Parameter_Specification =>
|
Make_Loop_Parameter_Specification (Loc,
|
Make_Loop_Parameter_Specification (Loc,
|
Defining_Identifier => Lnn (J),
|
Defining_Identifier => Lnn (J),
|
Reverse_Present => Rev,
|
Reverse_Present => Rev,
|
Discrete_Subtype_Definition =>
|
Discrete_Subtype_Definition =>
|
New_Reference_To (L_Index_Type (J), Loc))),
|
New_Reference_To (L_Index_Type (J), Loc))),
|
|
|
Statements => New_List (Assign, Build_Step (J))))));
|
Statements => New_List (Assign, Build_Step (J))))));
|
end loop;
|
end loop;
|
|
|
return Assign;
|
return Assign;
|
end Expand_Assign_Array_Loop;
|
end Expand_Assign_Array_Loop;
|
|
|
--------------------------
|
--------------------------
|
-- Expand_Assign_Record --
|
-- Expand_Assign_Record --
|
--------------------------
|
--------------------------
|
|
|
procedure Expand_Assign_Record (N : Node_Id) is
|
procedure Expand_Assign_Record (N : Node_Id) is
|
Lhs : constant Node_Id := Name (N);
|
Lhs : constant Node_Id := Name (N);
|
Rhs : Node_Id := Expression (N);
|
Rhs : Node_Id := Expression (N);
|
L_Typ : constant Entity_Id := Base_Type (Etype (Lhs));
|
L_Typ : constant Entity_Id := Base_Type (Etype (Lhs));
|
|
|
begin
|
begin
|
-- If change of representation, then extract the real right hand side
|
-- If change of representation, then extract the real right hand side
|
-- from the type conversion, and proceed with component-wise assignment,
|
-- from the type conversion, and proceed with component-wise assignment,
|
-- since the two types are not the same as far as the back end is
|
-- since the two types are not the same as far as the back end is
|
-- concerned.
|
-- concerned.
|
|
|
if Change_Of_Representation (N) then
|
if Change_Of_Representation (N) then
|
Rhs := Expression (Rhs);
|
Rhs := Expression (Rhs);
|
|
|
-- If this may be a case of a large bit aligned component, then proceed
|
-- If this may be a case of a large bit aligned component, then proceed
|
-- with component-wise assignment, to avoid possible clobbering of other
|
-- with component-wise assignment, to avoid possible clobbering of other
|
-- components sharing bits in the first or last byte of the component to
|
-- components sharing bits in the first or last byte of the component to
|
-- be assigned.
|
-- be assigned.
|
|
|
elsif Possible_Bit_Aligned_Component (Lhs)
|
elsif Possible_Bit_Aligned_Component (Lhs)
|
or
|
or
|
Possible_Bit_Aligned_Component (Rhs)
|
Possible_Bit_Aligned_Component (Rhs)
|
then
|
then
|
null;
|
null;
|
|
|
-- If we have a tagged type that has a complete record representation
|
-- If we have a tagged type that has a complete record representation
|
-- clause, we must do we must do component-wise assignments, since child
|
-- clause, we must do we must do component-wise assignments, since child
|
-- types may have used gaps for their components, and we might be
|
-- types may have used gaps for their components, and we might be
|
-- dealing with a view conversion.
|
-- dealing with a view conversion.
|
|
|
elsif Is_Fully_Repped_Tagged_Type (L_Typ) then
|
elsif Is_Fully_Repped_Tagged_Type (L_Typ) then
|
null;
|
null;
|
|
|
-- If neither condition met, then nothing special to do, the back end
|
-- If neither condition met, then nothing special to do, the back end
|
-- can handle assignment of the entire component as a single entity.
|
-- can handle assignment of the entire component as a single entity.
|
|
|
else
|
else
|
return;
|
return;
|
end if;
|
end if;
|
|
|
-- At this stage we know that we must do a component wise assignment
|
-- At this stage we know that we must do a component wise assignment
|
|
|
declare
|
declare
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
R_Typ : constant Entity_Id := Base_Type (Etype (Rhs));
|
R_Typ : constant Entity_Id := Base_Type (Etype (Rhs));
|
Decl : constant Node_Id := Declaration_Node (R_Typ);
|
Decl : constant Node_Id := Declaration_Node (R_Typ);
|
RDef : Node_Id;
|
RDef : Node_Id;
|
F : Entity_Id;
|
F : Entity_Id;
|
|
|
function Find_Component
|
function Find_Component
|
(Typ : Entity_Id;
|
(Typ : Entity_Id;
|
Comp : Entity_Id) return Entity_Id;
|
Comp : Entity_Id) return Entity_Id;
|
-- Find the component with the given name in the underlying record
|
-- Find the component with the given name in the underlying record
|
-- declaration for Typ. We need to use the actual entity because the
|
-- declaration for Typ. We need to use the actual entity because the
|
-- type may be private and resolution by identifier alone would fail.
|
-- type may be private and resolution by identifier alone would fail.
|
|
|
function Make_Component_List_Assign
|
function Make_Component_List_Assign
|
(CL : Node_Id;
|
(CL : Node_Id;
|
U_U : Boolean := False) return List_Id;
|
U_U : Boolean := False) return List_Id;
|
-- Returns a sequence of statements to assign the components that
|
-- Returns a sequence of statements to assign the components that
|
-- are referenced in the given component list. The flag U_U is
|
-- are referenced in the given component list. The flag U_U is
|
-- used to force the usage of the inferred value of the variant
|
-- used to force the usage of the inferred value of the variant
|
-- part expression as the switch for the generated case statement.
|
-- part expression as the switch for the generated case statement.
|
|
|
function Make_Field_Assign
|
function Make_Field_Assign
|
(C : Entity_Id;
|
(C : Entity_Id;
|
U_U : Boolean := False) return Node_Id;
|
U_U : Boolean := False) return Node_Id;
|
-- Given C, the entity for a discriminant or component, build an
|
-- Given C, the entity for a discriminant or component, build an
|
-- assignment for the corresponding field values. The flag U_U
|
-- assignment for the corresponding field values. The flag U_U
|
-- signals the presence of an Unchecked_Union and forces the usage
|
-- signals the presence of an Unchecked_Union and forces the usage
|
-- of the inferred discriminant value of C as the right hand side
|
-- of the inferred discriminant value of C as the right hand side
|
-- of the assignment.
|
-- of the assignment.
|
|
|
function Make_Field_Assigns (CI : List_Id) return List_Id;
|
function Make_Field_Assigns (CI : List_Id) return List_Id;
|
-- Given CI, a component items list, construct series of statements
|
-- Given CI, a component items list, construct series of statements
|
-- for fieldwise assignment of the corresponding components.
|
-- for fieldwise assignment of the corresponding components.
|
|
|
--------------------
|
--------------------
|
-- Find_Component --
|
-- Find_Component --
|
--------------------
|
--------------------
|
|
|
function Find_Component
|
function Find_Component
|
(Typ : Entity_Id;
|
(Typ : Entity_Id;
|
Comp : Entity_Id) return Entity_Id
|
Comp : Entity_Id) return Entity_Id
|
is
|
is
|
Utyp : constant Entity_Id := Underlying_Type (Typ);
|
Utyp : constant Entity_Id := Underlying_Type (Typ);
|
C : Entity_Id;
|
C : Entity_Id;
|
|
|
begin
|
begin
|
C := First_Entity (Utyp);
|
C := First_Entity (Utyp);
|
while Present (C) loop
|
while Present (C) loop
|
if Chars (C) = Chars (Comp) then
|
if Chars (C) = Chars (Comp) then
|
return C;
|
return C;
|
end if;
|
end if;
|
|
|
Next_Entity (C);
|
Next_Entity (C);
|
end loop;
|
end loop;
|
|
|
raise Program_Error;
|
raise Program_Error;
|
end Find_Component;
|
end Find_Component;
|
|
|
--------------------------------
|
--------------------------------
|
-- Make_Component_List_Assign --
|
-- Make_Component_List_Assign --
|
--------------------------------
|
--------------------------------
|
|
|
function Make_Component_List_Assign
|
function Make_Component_List_Assign
|
(CL : Node_Id;
|
(CL : Node_Id;
|
U_U : Boolean := False) return List_Id
|
U_U : Boolean := False) return List_Id
|
is
|
is
|
CI : constant List_Id := Component_Items (CL);
|
CI : constant List_Id := Component_Items (CL);
|
VP : constant Node_Id := Variant_Part (CL);
|
VP : constant Node_Id := Variant_Part (CL);
|
|
|
Alts : List_Id;
|
Alts : List_Id;
|
DC : Node_Id;
|
DC : Node_Id;
|
DCH : List_Id;
|
DCH : List_Id;
|
Expr : Node_Id;
|
Expr : Node_Id;
|
Result : List_Id;
|
Result : List_Id;
|
V : Node_Id;
|
V : Node_Id;
|
|
|
begin
|
begin
|
Result := Make_Field_Assigns (CI);
|
Result := Make_Field_Assigns (CI);
|
|
|
if Present (VP) then
|
if Present (VP) then
|
V := First_Non_Pragma (Variants (VP));
|
V := First_Non_Pragma (Variants (VP));
|
Alts := New_List;
|
Alts := New_List;
|
while Present (V) loop
|
while Present (V) loop
|
DCH := New_List;
|
DCH := New_List;
|
DC := First (Discrete_Choices (V));
|
DC := First (Discrete_Choices (V));
|
while Present (DC) loop
|
while Present (DC) loop
|
Append_To (DCH, New_Copy_Tree (DC));
|
Append_To (DCH, New_Copy_Tree (DC));
|
Next (DC);
|
Next (DC);
|
end loop;
|
end loop;
|
|
|
Append_To (Alts,
|
Append_To (Alts,
|
Make_Case_Statement_Alternative (Loc,
|
Make_Case_Statement_Alternative (Loc,
|
Discrete_Choices => DCH,
|
Discrete_Choices => DCH,
|
Statements =>
|
Statements =>
|
Make_Component_List_Assign (Component_List (V))));
|
Make_Component_List_Assign (Component_List (V))));
|
Next_Non_Pragma (V);
|
Next_Non_Pragma (V);
|
end loop;
|
end loop;
|
|
|
-- If we have an Unchecked_Union, use the value of the inferred
|
-- If we have an Unchecked_Union, use the value of the inferred
|
-- discriminant of the variant part expression as the switch
|
-- discriminant of the variant part expression as the switch
|
-- for the case statement. The case statement may later be
|
-- for the case statement. The case statement may later be
|
-- folded.
|
-- folded.
|
|
|
if U_U then
|
if U_U then
|
Expr :=
|
Expr :=
|
New_Copy (Get_Discriminant_Value (
|
New_Copy (Get_Discriminant_Value (
|
Entity (Name (VP)),
|
Entity (Name (VP)),
|
Etype (Rhs),
|
Etype (Rhs),
|
Discriminant_Constraint (Etype (Rhs))));
|
Discriminant_Constraint (Etype (Rhs))));
|
else
|
else
|
Expr :=
|
Expr :=
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr (Rhs),
|
Prefix => Duplicate_Subexpr (Rhs),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Chars (Name (VP))));
|
Make_Identifier (Loc, Chars (Name (VP))));
|
end if;
|
end if;
|
|
|
Append_To (Result,
|
Append_To (Result,
|
Make_Case_Statement (Loc,
|
Make_Case_Statement (Loc,
|
Expression => Expr,
|
Expression => Expr,
|
Alternatives => Alts));
|
Alternatives => Alts));
|
end if;
|
end if;
|
|
|
return Result;
|
return Result;
|
end Make_Component_List_Assign;
|
end Make_Component_List_Assign;
|
|
|
-----------------------
|
-----------------------
|
-- Make_Field_Assign --
|
-- Make_Field_Assign --
|
-----------------------
|
-----------------------
|
|
|
function Make_Field_Assign
|
function Make_Field_Assign
|
(C : Entity_Id;
|
(C : Entity_Id;
|
U_U : Boolean := False) return Node_Id
|
U_U : Boolean := False) return Node_Id
|
is
|
is
|
A : Node_Id;
|
A : Node_Id;
|
Expr : Node_Id;
|
Expr : Node_Id;
|
|
|
begin
|
begin
|
-- In the case of an Unchecked_Union, use the discriminant
|
-- In the case of an Unchecked_Union, use the discriminant
|
-- constraint value as on the right hand side of the assignment.
|
-- constraint value as on the right hand side of the assignment.
|
|
|
if U_U then
|
if U_U then
|
Expr :=
|
Expr :=
|
New_Copy (Get_Discriminant_Value (C,
|
New_Copy (Get_Discriminant_Value (C,
|
Etype (Rhs),
|
Etype (Rhs),
|
Discriminant_Constraint (Etype (Rhs))));
|
Discriminant_Constraint (Etype (Rhs))));
|
else
|
else
|
Expr :=
|
Expr :=
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr (Rhs),
|
Prefix => Duplicate_Subexpr (Rhs),
|
Selector_Name => New_Occurrence_Of (C, Loc));
|
Selector_Name => New_Occurrence_Of (C, Loc));
|
end if;
|
end if;
|
|
|
A :=
|
A :=
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name =>
|
Name =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr (Lhs),
|
Prefix => Duplicate_Subexpr (Lhs),
|
Selector_Name =>
|
Selector_Name =>
|
New_Occurrence_Of (Find_Component (L_Typ, C), Loc)),
|
New_Occurrence_Of (Find_Component (L_Typ, C), Loc)),
|
Expression => Expr);
|
Expression => Expr);
|
|
|
-- Set Assignment_OK, so discriminants can be assigned
|
-- Set Assignment_OK, so discriminants can be assigned
|
|
|
Set_Assignment_OK (Name (A), True);
|
Set_Assignment_OK (Name (A), True);
|
|
|
if Componentwise_Assignment (N)
|
if Componentwise_Assignment (N)
|
and then Nkind (Name (A)) = N_Selected_Component
|
and then Nkind (Name (A)) = N_Selected_Component
|
and then Chars (Selector_Name (Name (A))) = Name_uParent
|
and then Chars (Selector_Name (Name (A))) = Name_uParent
|
then
|
then
|
Set_Componentwise_Assignment (A);
|
Set_Componentwise_Assignment (A);
|
end if;
|
end if;
|
|
|
return A;
|
return A;
|
end Make_Field_Assign;
|
end Make_Field_Assign;
|
|
|
------------------------
|
------------------------
|
-- Make_Field_Assigns --
|
-- Make_Field_Assigns --
|
------------------------
|
------------------------
|
|
|
function Make_Field_Assigns (CI : List_Id) return List_Id is
|
function Make_Field_Assigns (CI : List_Id) return List_Id is
|
Item : Node_Id;
|
Item : Node_Id;
|
Result : List_Id;
|
Result : List_Id;
|
|
|
begin
|
begin
|
Item := First (CI);
|
Item := First (CI);
|
Result := New_List;
|
Result := New_List;
|
|
|
while Present (Item) loop
|
while Present (Item) loop
|
|
|
-- Look for components, but exclude _tag field assignment if
|
-- Look for components, but exclude _tag field assignment if
|
-- the special Componentwise_Assignment flag is set.
|
-- the special Componentwise_Assignment flag is set.
|
|
|
if Nkind (Item) = N_Component_Declaration
|
if Nkind (Item) = N_Component_Declaration
|
and then not (Is_Tag (Defining_Identifier (Item))
|
and then not (Is_Tag (Defining_Identifier (Item))
|
and then Componentwise_Assignment (N))
|
and then Componentwise_Assignment (N))
|
then
|
then
|
Append_To
|
Append_To
|
(Result, Make_Field_Assign (Defining_Identifier (Item)));
|
(Result, Make_Field_Assign (Defining_Identifier (Item)));
|
end if;
|
end if;
|
|
|
Next (Item);
|
Next (Item);
|
end loop;
|
end loop;
|
|
|
return Result;
|
return Result;
|
end Make_Field_Assigns;
|
end Make_Field_Assigns;
|
|
|
-- Start of processing for Expand_Assign_Record
|
-- Start of processing for Expand_Assign_Record
|
|
|
begin
|
begin
|
-- Note that we use the base types for this processing. This results
|
-- Note that we use the base types for this processing. This results
|
-- in some extra work in the constrained case, but the change of
|
-- in some extra work in the constrained case, but the change of
|
-- representation case is so unusual that it is not worth the effort.
|
-- representation case is so unusual that it is not worth the effort.
|
|
|
-- First copy the discriminants. This is done unconditionally. It
|
-- First copy the discriminants. This is done unconditionally. It
|
-- is required in the unconstrained left side case, and also in the
|
-- is required in the unconstrained left side case, and also in the
|
-- case where this assignment was constructed during the expansion
|
-- case where this assignment was constructed during the expansion
|
-- of a type conversion (since initialization of discriminants is
|
-- of a type conversion (since initialization of discriminants is
|
-- suppressed in this case). It is unnecessary but harmless in
|
-- suppressed in this case). It is unnecessary but harmless in
|
-- other cases.
|
-- other cases.
|
|
|
if Has_Discriminants (L_Typ) then
|
if Has_Discriminants (L_Typ) then
|
F := First_Discriminant (R_Typ);
|
F := First_Discriminant (R_Typ);
|
while Present (F) loop
|
while Present (F) loop
|
|
|
-- If we are expanding the initialization of a derived record
|
-- If we are expanding the initialization of a derived record
|
-- that constrains or renames discriminants of the parent, we
|
-- that constrains or renames discriminants of the parent, we
|
-- must use the corresponding discriminant in the parent.
|
-- must use the corresponding discriminant in the parent.
|
|
|
declare
|
declare
|
CF : Entity_Id;
|
CF : Entity_Id;
|
|
|
begin
|
begin
|
if Inside_Init_Proc
|
if Inside_Init_Proc
|
and then Present (Corresponding_Discriminant (F))
|
and then Present (Corresponding_Discriminant (F))
|
then
|
then
|
CF := Corresponding_Discriminant (F);
|
CF := Corresponding_Discriminant (F);
|
else
|
else
|
CF := F;
|
CF := F;
|
end if;
|
end if;
|
|
|
if Is_Unchecked_Union (Base_Type (R_Typ)) then
|
if Is_Unchecked_Union (Base_Type (R_Typ)) then
|
|
|
-- Within an initialization procedure this is the
|
-- Within an initialization procedure this is the
|
-- assignment to an unchecked union component, in which
|
-- assignment to an unchecked union component, in which
|
-- case there is no discriminant to initialize.
|
-- case there is no discriminant to initialize.
|
|
|
if Inside_Init_Proc then
|
if Inside_Init_Proc then
|
null;
|
null;
|
|
|
else
|
else
|
-- The assignment is part of a conversion from a
|
-- The assignment is part of a conversion from a
|
-- derived unchecked union type with an inferable
|
-- derived unchecked union type with an inferable
|
-- discriminant, to a parent type.
|
-- discriminant, to a parent type.
|
|
|
Insert_Action (N, Make_Field_Assign (CF, True));
|
Insert_Action (N, Make_Field_Assign (CF, True));
|
end if;
|
end if;
|
|
|
else
|
else
|
Insert_Action (N, Make_Field_Assign (CF));
|
Insert_Action (N, Make_Field_Assign (CF));
|
end if;
|
end if;
|
|
|
Next_Discriminant (F);
|
Next_Discriminant (F);
|
end;
|
end;
|
end loop;
|
end loop;
|
end if;
|
end if;
|
|
|
-- We know the underlying type is a record, but its current view
|
-- We know the underlying type is a record, but its current view
|
-- may be private. We must retrieve the usable record declaration.
|
-- may be private. We must retrieve the usable record declaration.
|
|
|
if Nkind_In (Decl, N_Private_Type_Declaration,
|
if Nkind_In (Decl, N_Private_Type_Declaration,
|
N_Private_Extension_Declaration)
|
N_Private_Extension_Declaration)
|
and then Present (Full_View (R_Typ))
|
and then Present (Full_View (R_Typ))
|
then
|
then
|
RDef := Type_Definition (Declaration_Node (Full_View (R_Typ)));
|
RDef := Type_Definition (Declaration_Node (Full_View (R_Typ)));
|
else
|
else
|
RDef := Type_Definition (Decl);
|
RDef := Type_Definition (Decl);
|
end if;
|
end if;
|
|
|
if Nkind (RDef) = N_Derived_Type_Definition then
|
if Nkind (RDef) = N_Derived_Type_Definition then
|
RDef := Record_Extension_Part (RDef);
|
RDef := Record_Extension_Part (RDef);
|
end if;
|
end if;
|
|
|
if Nkind (RDef) = N_Record_Definition
|
if Nkind (RDef) = N_Record_Definition
|
and then Present (Component_List (RDef))
|
and then Present (Component_List (RDef))
|
then
|
then
|
if Is_Unchecked_Union (R_Typ) then
|
if Is_Unchecked_Union (R_Typ) then
|
Insert_Actions (N,
|
Insert_Actions (N,
|
Make_Component_List_Assign (Component_List (RDef), True));
|
Make_Component_List_Assign (Component_List (RDef), True));
|
else
|
else
|
Insert_Actions
|
Insert_Actions
|
(N, Make_Component_List_Assign (Component_List (RDef)));
|
(N, Make_Component_List_Assign (Component_List (RDef)));
|
end if;
|
end if;
|
|
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
end if;
|
end if;
|
end;
|
end;
|
end Expand_Assign_Record;
|
end Expand_Assign_Record;
|
|
|
-----------------------------------
|
-----------------------------------
|
-- Expand_N_Assignment_Statement --
|
-- Expand_N_Assignment_Statement --
|
-----------------------------------
|
-----------------------------------
|
|
|
-- This procedure implements various cases where an assignment statement
|
-- This procedure implements various cases where an assignment statement
|
-- cannot just be passed on to the back end in untransformed state.
|
-- cannot just be passed on to the back end in untransformed state.
|
|
|
procedure Expand_N_Assignment_Statement (N : Node_Id) is
|
procedure Expand_N_Assignment_Statement (N : Node_Id) is
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Crep : constant Boolean := Change_Of_Representation (N);
|
Crep : constant Boolean := Change_Of_Representation (N);
|
Lhs : constant Node_Id := Name (N);
|
Lhs : constant Node_Id := Name (N);
|
Rhs : constant Node_Id := Expression (N);
|
Rhs : constant Node_Id := Expression (N);
|
Typ : constant Entity_Id := Underlying_Type (Etype (Lhs));
|
Typ : constant Entity_Id := Underlying_Type (Etype (Lhs));
|
Exp : Node_Id;
|
Exp : Node_Id;
|
|
|
begin
|
begin
|
-- Special case to check right away, if the Componentwise_Assignment
|
-- Special case to check right away, if the Componentwise_Assignment
|
-- flag is set, this is a reanalysis from the expansion of the primitive
|
-- flag is set, this is a reanalysis from the expansion of the primitive
|
-- assignment procedure for a tagged type, and all we need to do is to
|
-- assignment procedure for a tagged type, and all we need to do is to
|
-- expand to assignment of components, because otherwise, we would get
|
-- expand to assignment of components, because otherwise, we would get
|
-- infinite recursion (since this looks like a tagged assignment which
|
-- infinite recursion (since this looks like a tagged assignment which
|
-- would normally try to *call* the primitive assignment procedure).
|
-- would normally try to *call* the primitive assignment procedure).
|
|
|
if Componentwise_Assignment (N) then
|
if Componentwise_Assignment (N) then
|
Expand_Assign_Record (N);
|
Expand_Assign_Record (N);
|
return;
|
return;
|
end if;
|
end if;
|
|
|
-- Defend against invalid subscripts on left side if we are in standard
|
-- Defend against invalid subscripts on left side if we are in standard
|
-- validity checking mode. No need to do this if we are checking all
|
-- validity checking mode. No need to do this if we are checking all
|
-- subscripts.
|
-- subscripts.
|
|
|
-- Note that we do this right away, because there are some early return
|
-- Note that we do this right away, because there are some early return
|
-- paths in this procedure, and this is required on all paths.
|
-- paths in this procedure, and this is required on all paths.
|
|
|
if Validity_Checks_On
|
if Validity_Checks_On
|
and then Validity_Check_Default
|
and then Validity_Check_Default
|
and then not Validity_Check_Subscripts
|
and then not Validity_Check_Subscripts
|
then
|
then
|
Check_Valid_Lvalue_Subscripts (Lhs);
|
Check_Valid_Lvalue_Subscripts (Lhs);
|
end if;
|
end if;
|
|
|
-- Ada 2005 (AI-327): Handle assignment to priority of protected object
|
-- Ada 2005 (AI-327): Handle assignment to priority of protected object
|
|
|
-- Rewrite an assignment to X'Priority into a run-time call
|
-- Rewrite an assignment to X'Priority into a run-time call
|
|
|
-- For example: X'Priority := New_Prio_Expr;
|
-- For example: X'Priority := New_Prio_Expr;
|
-- ...is expanded into Set_Ceiling (X._Object, New_Prio_Expr);
|
-- ...is expanded into Set_Ceiling (X._Object, New_Prio_Expr);
|
|
|
-- Note that although X'Priority is notionally an object, it is quite
|
-- Note that although X'Priority is notionally an object, it is quite
|
-- deliberately not defined as an aliased object in the RM. This means
|
-- deliberately not defined as an aliased object in the RM. This means
|
-- that it works fine to rewrite it as a call, without having to worry
|
-- that it works fine to rewrite it as a call, without having to worry
|
-- about complications that would other arise from X'Priority'Access,
|
-- about complications that would other arise from X'Priority'Access,
|
-- which is illegal, because of the lack of aliasing.
|
-- which is illegal, because of the lack of aliasing.
|
|
|
if Ada_Version >= Ada_2005 then
|
if Ada_Version >= Ada_2005 then
|
declare
|
declare
|
Call : Node_Id;
|
Call : Node_Id;
|
Conctyp : Entity_Id;
|
Conctyp : Entity_Id;
|
Ent : Entity_Id;
|
Ent : Entity_Id;
|
Subprg : Entity_Id;
|
Subprg : Entity_Id;
|
RT_Subprg_Name : Node_Id;
|
RT_Subprg_Name : Node_Id;
|
|
|
begin
|
begin
|
-- Handle chains of renamings
|
-- Handle chains of renamings
|
|
|
Ent := Name (N);
|
Ent := Name (N);
|
while Nkind (Ent) in N_Has_Entity
|
while Nkind (Ent) in N_Has_Entity
|
and then Present (Entity (Ent))
|
and then Present (Entity (Ent))
|
and then Present (Renamed_Object (Entity (Ent)))
|
and then Present (Renamed_Object (Entity (Ent)))
|
loop
|
loop
|
Ent := Renamed_Object (Entity (Ent));
|
Ent := Renamed_Object (Entity (Ent));
|
end loop;
|
end loop;
|
|
|
-- The attribute Priority applied to protected objects has been
|
-- The attribute Priority applied to protected objects has been
|
-- previously expanded into a call to the Get_Ceiling run-time
|
-- previously expanded into a call to the Get_Ceiling run-time
|
-- subprogram.
|
-- subprogram.
|
|
|
if Nkind (Ent) = N_Function_Call
|
if Nkind (Ent) = N_Function_Call
|
and then (Entity (Name (Ent)) = RTE (RE_Get_Ceiling)
|
and then (Entity (Name (Ent)) = RTE (RE_Get_Ceiling)
|
or else
|
or else
|
Entity (Name (Ent)) = RTE (RO_PE_Get_Ceiling))
|
Entity (Name (Ent)) = RTE (RO_PE_Get_Ceiling))
|
then
|
then
|
-- Look for the enclosing concurrent type
|
-- Look for the enclosing concurrent type
|
|
|
Conctyp := Current_Scope;
|
Conctyp := Current_Scope;
|
while not Is_Concurrent_Type (Conctyp) loop
|
while not Is_Concurrent_Type (Conctyp) loop
|
Conctyp := Scope (Conctyp);
|
Conctyp := Scope (Conctyp);
|
end loop;
|
end loop;
|
|
|
pragma Assert (Is_Protected_Type (Conctyp));
|
pragma Assert (Is_Protected_Type (Conctyp));
|
|
|
-- Generate the first actual of the call
|
-- Generate the first actual of the call
|
|
|
Subprg := Current_Scope;
|
Subprg := Current_Scope;
|
while not Present (Protected_Body_Subprogram (Subprg)) loop
|
while not Present (Protected_Body_Subprogram (Subprg)) loop
|
Subprg := Scope (Subprg);
|
Subprg := Scope (Subprg);
|
end loop;
|
end loop;
|
|
|
-- Select the appropriate run-time call
|
-- Select the appropriate run-time call
|
|
|
if Number_Entries (Conctyp) = 0 then
|
if Number_Entries (Conctyp) = 0 then
|
RT_Subprg_Name :=
|
RT_Subprg_Name :=
|
New_Reference_To (RTE (RE_Set_Ceiling), Loc);
|
New_Reference_To (RTE (RE_Set_Ceiling), Loc);
|
else
|
else
|
RT_Subprg_Name :=
|
RT_Subprg_Name :=
|
New_Reference_To (RTE (RO_PE_Set_Ceiling), Loc);
|
New_Reference_To (RTE (RO_PE_Set_Ceiling), Loc);
|
end if;
|
end if;
|
|
|
Call :=
|
Call :=
|
Make_Procedure_Call_Statement (Loc,
|
Make_Procedure_Call_Statement (Loc,
|
Name => RT_Subprg_Name,
|
Name => RT_Subprg_Name,
|
Parameter_Associations => New_List (
|
Parameter_Associations => New_List (
|
New_Copy_Tree (First (Parameter_Associations (Ent))),
|
New_Copy_Tree (First (Parameter_Associations (Ent))),
|
Relocate_Node (Expression (N))));
|
Relocate_Node (Expression (N))));
|
|
|
Rewrite (N, Call);
|
Rewrite (N, Call);
|
Analyze (N);
|
Analyze (N);
|
return;
|
return;
|
end if;
|
end if;
|
end;
|
end;
|
end if;
|
end if;
|
|
|
-- Deal with assignment checks unless suppressed
|
-- Deal with assignment checks unless suppressed
|
|
|
if not Suppress_Assignment_Checks (N) then
|
if not Suppress_Assignment_Checks (N) then
|
|
|
-- First deal with generation of range check if required
|
-- First deal with generation of range check if required
|
|
|
if Do_Range_Check (Rhs) then
|
if Do_Range_Check (Rhs) then
|
Set_Do_Range_Check (Rhs, False);
|
Set_Do_Range_Check (Rhs, False);
|
Generate_Range_Check (Rhs, Typ, CE_Range_Check_Failed);
|
Generate_Range_Check (Rhs, Typ, CE_Range_Check_Failed);
|
end if;
|
end if;
|
|
|
-- Then generate predicate check if required
|
-- Then generate predicate check if required
|
|
|
Apply_Predicate_Check (Rhs, Typ);
|
Apply_Predicate_Check (Rhs, Typ);
|
end if;
|
end if;
|
|
|
-- Check for a special case where a high level transformation is
|
-- Check for a special case where a high level transformation is
|
-- required. If we have either of:
|
-- required. If we have either of:
|
|
|
-- P.field := rhs;
|
-- P.field := rhs;
|
-- P (sub) := rhs;
|
-- P (sub) := rhs;
|
|
|
-- where P is a reference to a bit packed array, then we have to unwind
|
-- where P is a reference to a bit packed array, then we have to unwind
|
-- the assignment. The exact meaning of being a reference to a bit
|
-- the assignment. The exact meaning of being a reference to a bit
|
-- packed array is as follows:
|
-- packed array is as follows:
|
|
|
-- An indexed component whose prefix is a bit packed array is a
|
-- An indexed component whose prefix is a bit packed array is a
|
-- reference to a bit packed array.
|
-- reference to a bit packed array.
|
|
|
-- An indexed component or selected component whose prefix is a
|
-- An indexed component or selected component whose prefix is a
|
-- reference to a bit packed array is itself a reference ot a
|
-- reference to a bit packed array is itself a reference ot a
|
-- bit packed array.
|
-- bit packed array.
|
|
|
-- The required transformation is
|
-- The required transformation is
|
|
|
-- Tnn : prefix_type := P;
|
-- Tnn : prefix_type := P;
|
-- Tnn.field := rhs;
|
-- Tnn.field := rhs;
|
-- P := Tnn;
|
-- P := Tnn;
|
|
|
-- or
|
-- or
|
|
|
-- Tnn : prefix_type := P;
|
-- Tnn : prefix_type := P;
|
-- Tnn (subscr) := rhs;
|
-- Tnn (subscr) := rhs;
|
-- P := Tnn;
|
-- P := Tnn;
|
|
|
-- Since P is going to be evaluated more than once, any subscripts
|
-- Since P is going to be evaluated more than once, any subscripts
|
-- in P must have their evaluation forced.
|
-- in P must have their evaluation forced.
|
|
|
if Nkind_In (Lhs, N_Indexed_Component, N_Selected_Component)
|
if Nkind_In (Lhs, N_Indexed_Component, N_Selected_Component)
|
and then Is_Ref_To_Bit_Packed_Array (Prefix (Lhs))
|
and then Is_Ref_To_Bit_Packed_Array (Prefix (Lhs))
|
then
|
then
|
declare
|
declare
|
BPAR_Expr : constant Node_Id := Relocate_Node (Prefix (Lhs));
|
BPAR_Expr : constant Node_Id := Relocate_Node (Prefix (Lhs));
|
BPAR_Typ : constant Entity_Id := Etype (BPAR_Expr);
|
BPAR_Typ : constant Entity_Id := Etype (BPAR_Expr);
|
Tnn : constant Entity_Id :=
|
Tnn : constant Entity_Id :=
|
Make_Temporary (Loc, 'T', BPAR_Expr);
|
Make_Temporary (Loc, 'T', BPAR_Expr);
|
|
|
begin
|
begin
|
-- Insert the post assignment first, because we want to copy the
|
-- Insert the post assignment first, because we want to copy the
|
-- BPAR_Expr tree before it gets analyzed in the context of the
|
-- BPAR_Expr tree before it gets analyzed in the context of the
|
-- pre assignment. Note that we do not analyze the post assignment
|
-- pre assignment. Note that we do not analyze the post assignment
|
-- yet (we cannot till we have completed the analysis of the pre
|
-- yet (we cannot till we have completed the analysis of the pre
|
-- assignment). As usual, the analysis of this post assignment
|
-- assignment). As usual, the analysis of this post assignment
|
-- will happen on its own when we "run into" it after finishing
|
-- will happen on its own when we "run into" it after finishing
|
-- the current assignment.
|
-- the current assignment.
|
|
|
Insert_After (N,
|
Insert_After (N,
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => New_Copy_Tree (BPAR_Expr),
|
Name => New_Copy_Tree (BPAR_Expr),
|
Expression => New_Occurrence_Of (Tnn, Loc)));
|
Expression => New_Occurrence_Of (Tnn, Loc)));
|
|
|
-- At this stage BPAR_Expr is a reference to a bit packed array
|
-- At this stage BPAR_Expr is a reference to a bit packed array
|
-- where the reference was not expanded in the original tree,
|
-- where the reference was not expanded in the original tree,
|
-- since it was on the left side of an assignment. But in the
|
-- since it was on the left side of an assignment. But in the
|
-- pre-assignment statement (the object definition), BPAR_Expr
|
-- pre-assignment statement (the object definition), BPAR_Expr
|
-- will end up on the right hand side, and must be reexpanded. To
|
-- will end up on the right hand side, and must be reexpanded. To
|
-- achieve this, we reset the analyzed flag of all selected and
|
-- achieve this, we reset the analyzed flag of all selected and
|
-- indexed components down to the actual indexed component for
|
-- indexed components down to the actual indexed component for
|
-- the packed array.
|
-- the packed array.
|
|
|
Exp := BPAR_Expr;
|
Exp := BPAR_Expr;
|
loop
|
loop
|
Set_Analyzed (Exp, False);
|
Set_Analyzed (Exp, False);
|
|
|
if Nkind_In
|
if Nkind_In
|
(Exp, N_Selected_Component, N_Indexed_Component)
|
(Exp, N_Selected_Component, N_Indexed_Component)
|
then
|
then
|
Exp := Prefix (Exp);
|
Exp := Prefix (Exp);
|
else
|
else
|
exit;
|
exit;
|
end if;
|
end if;
|
end loop;
|
end loop;
|
|
|
-- Now we can insert and analyze the pre-assignment
|
-- Now we can insert and analyze the pre-assignment
|
|
|
-- If the right-hand side requires a transient scope, it has
|
-- If the right-hand side requires a transient scope, it has
|
-- already been placed on the stack. However, the declaration is
|
-- already been placed on the stack. However, the declaration is
|
-- inserted in the tree outside of this scope, and must reflect
|
-- inserted in the tree outside of this scope, and must reflect
|
-- the proper scope for its variable. This awkward bit is forced
|
-- the proper scope for its variable. This awkward bit is forced
|
-- by the stricter scope discipline imposed by GCC 2.97.
|
-- by the stricter scope discipline imposed by GCC 2.97.
|
|
|
declare
|
declare
|
Uses_Transient_Scope : constant Boolean :=
|
Uses_Transient_Scope : constant Boolean :=
|
Scope_Is_Transient
|
Scope_Is_Transient
|
and then N = Node_To_Be_Wrapped;
|
and then N = Node_To_Be_Wrapped;
|
|
|
begin
|
begin
|
if Uses_Transient_Scope then
|
if Uses_Transient_Scope then
|
Push_Scope (Scope (Current_Scope));
|
Push_Scope (Scope (Current_Scope));
|
end if;
|
end if;
|
|
|
Insert_Before_And_Analyze (N,
|
Insert_Before_And_Analyze (N,
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Tnn,
|
Defining_Identifier => Tnn,
|
Object_Definition => New_Occurrence_Of (BPAR_Typ, Loc),
|
Object_Definition => New_Occurrence_Of (BPAR_Typ, Loc),
|
Expression => BPAR_Expr));
|
Expression => BPAR_Expr));
|
|
|
if Uses_Transient_Scope then
|
if Uses_Transient_Scope then
|
Pop_Scope;
|
Pop_Scope;
|
end if;
|
end if;
|
end;
|
end;
|
|
|
-- Now fix up the original assignment and continue processing
|
-- Now fix up the original assignment and continue processing
|
|
|
Rewrite (Prefix (Lhs),
|
Rewrite (Prefix (Lhs),
|
New_Occurrence_Of (Tnn, Loc));
|
New_Occurrence_Of (Tnn, Loc));
|
|
|
-- We do not need to reanalyze that assignment, and we do not need
|
-- We do not need to reanalyze that assignment, and we do not need
|
-- to worry about references to the temporary, but we do need to
|
-- to worry about references to the temporary, but we do need to
|
-- make sure that the temporary is not marked as a true constant
|
-- make sure that the temporary is not marked as a true constant
|
-- since we now have a generated assignment to it!
|
-- since we now have a generated assignment to it!
|
|
|
Set_Is_True_Constant (Tnn, False);
|
Set_Is_True_Constant (Tnn, False);
|
end;
|
end;
|
end if;
|
end if;
|
|
|
-- When we have the appropriate type of aggregate in the expression (it
|
-- When we have the appropriate type of aggregate in the expression (it
|
-- has been determined during analysis of the aggregate by setting the
|
-- has been determined during analysis of the aggregate by setting the
|
-- delay flag), let's perform in place assignment and thus avoid
|
-- delay flag), let's perform in place assignment and thus avoid
|
-- creating a temporary.
|
-- creating a temporary.
|
|
|
if Is_Delayed_Aggregate (Rhs) then
|
if Is_Delayed_Aggregate (Rhs) then
|
Convert_Aggr_In_Assignment (N);
|
Convert_Aggr_In_Assignment (N);
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
Analyze (N);
|
Analyze (N);
|
return;
|
return;
|
end if;
|
end if;
|
|
|
-- Apply discriminant check if required. If Lhs is an access type to a
|
-- Apply discriminant check if required. If Lhs is an access type to a
|
-- designated type with discriminants, we must always check.
|
-- designated type with discriminants, we must always check.
|
|
|
if Has_Discriminants (Etype (Lhs)) then
|
if Has_Discriminants (Etype (Lhs)) then
|
|
|
-- Skip discriminant check if change of representation. Will be
|
-- Skip discriminant check if change of representation. Will be
|
-- done when the change of representation is expanded out.
|
-- done when the change of representation is expanded out.
|
|
|
if not Crep then
|
if not Crep then
|
Apply_Discriminant_Check (Rhs, Etype (Lhs), Lhs);
|
Apply_Discriminant_Check (Rhs, Etype (Lhs), Lhs);
|
end if;
|
end if;
|
|
|
-- If the type is private without discriminants, and the full type
|
-- If the type is private without discriminants, and the full type
|
-- has discriminants (necessarily with defaults) a check may still be
|
-- has discriminants (necessarily with defaults) a check may still be
|
-- necessary if the Lhs is aliased. The private discriminants must be
|
-- necessary if the Lhs is aliased. The private discriminants must be
|
-- visible to build the discriminant constraints.
|
-- visible to build the discriminant constraints.
|
|
|
-- Only an explicit dereference that comes from source indicates
|
-- Only an explicit dereference that comes from source indicates
|
-- aliasing. Access to formals of protected operations and entries
|
-- aliasing. Access to formals of protected operations and entries
|
-- create dereferences but are not semantic aliasings.
|
-- create dereferences but are not semantic aliasings.
|
|
|
elsif Is_Private_Type (Etype (Lhs))
|
elsif Is_Private_Type (Etype (Lhs))
|
and then Has_Discriminants (Typ)
|
and then Has_Discriminants (Typ)
|
and then Nkind (Lhs) = N_Explicit_Dereference
|
and then Nkind (Lhs) = N_Explicit_Dereference
|
and then Comes_From_Source (Lhs)
|
and then Comes_From_Source (Lhs)
|
then
|
then
|
declare
|
declare
|
Lt : constant Entity_Id := Etype (Lhs);
|
Lt : constant Entity_Id := Etype (Lhs);
|
Ubt : Entity_Id := Base_Type (Typ);
|
Ubt : Entity_Id := Base_Type (Typ);
|
|
|
begin
|
begin
|
-- In the case of an expander-generated record subtype whose base
|
-- In the case of an expander-generated record subtype whose base
|
-- type still appears private, Typ will have been set to that
|
-- type still appears private, Typ will have been set to that
|
-- private type rather than the underlying record type (because
|
-- private type rather than the underlying record type (because
|
-- Underlying type will have returned the record subtype), so it's
|
-- Underlying type will have returned the record subtype), so it's
|
-- necessary to apply Underlying_Type again to the base type to
|
-- necessary to apply Underlying_Type again to the base type to
|
-- get the record type we need for the discriminant check. Such
|
-- get the record type we need for the discriminant check. Such
|
-- subtypes can be created for assignments in certain cases, such
|
-- subtypes can be created for assignments in certain cases, such
|
-- as within an instantiation passed this kind of private type.
|
-- as within an instantiation passed this kind of private type.
|
-- It would be good to avoid this special test, but making changes
|
-- It would be good to avoid this special test, but making changes
|
-- to prevent this odd form of record subtype seems difficult. ???
|
-- to prevent this odd form of record subtype seems difficult. ???
|
|
|
if Is_Private_Type (Ubt) then
|
if Is_Private_Type (Ubt) then
|
Ubt := Underlying_Type (Ubt);
|
Ubt := Underlying_Type (Ubt);
|
end if;
|
end if;
|
|
|
Set_Etype (Lhs, Ubt);
|
Set_Etype (Lhs, Ubt);
|
Rewrite (Rhs, OK_Convert_To (Base_Type (Ubt), Rhs));
|
Rewrite (Rhs, OK_Convert_To (Base_Type (Ubt), Rhs));
|
Apply_Discriminant_Check (Rhs, Ubt, Lhs);
|
Apply_Discriminant_Check (Rhs, Ubt, Lhs);
|
Set_Etype (Lhs, Lt);
|
Set_Etype (Lhs, Lt);
|
end;
|
end;
|
|
|
-- If the Lhs has a private type with unknown discriminants, it
|
-- If the Lhs has a private type with unknown discriminants, it
|
-- may have a full view with discriminants, but those are nameable
|
-- may have a full view with discriminants, but those are nameable
|
-- only in the underlying type, so convert the Rhs to it before
|
-- only in the underlying type, so convert the Rhs to it before
|
-- potential checking.
|
-- potential checking.
|
|
|
elsif Has_Unknown_Discriminants (Base_Type (Etype (Lhs)))
|
elsif Has_Unknown_Discriminants (Base_Type (Etype (Lhs)))
|
and then Has_Discriminants (Typ)
|
and then Has_Discriminants (Typ)
|
then
|
then
|
Rewrite (Rhs, OK_Convert_To (Base_Type (Typ), Rhs));
|
Rewrite (Rhs, OK_Convert_To (Base_Type (Typ), Rhs));
|
Apply_Discriminant_Check (Rhs, Typ, Lhs);
|
Apply_Discriminant_Check (Rhs, Typ, Lhs);
|
|
|
-- In the access type case, we need the same discriminant check, and
|
-- In the access type case, we need the same discriminant check, and
|
-- also range checks if we have an access to constrained array.
|
-- also range checks if we have an access to constrained array.
|
|
|
elsif Is_Access_Type (Etype (Lhs))
|
elsif Is_Access_Type (Etype (Lhs))
|
and then Is_Constrained (Designated_Type (Etype (Lhs)))
|
and then Is_Constrained (Designated_Type (Etype (Lhs)))
|
then
|
then
|
if Has_Discriminants (Designated_Type (Etype (Lhs))) then
|
if Has_Discriminants (Designated_Type (Etype (Lhs))) then
|
|
|
-- Skip discriminant check if change of representation. Will be
|
-- Skip discriminant check if change of representation. Will be
|
-- done when the change of representation is expanded out.
|
-- done when the change of representation is expanded out.
|
|
|
if not Crep then
|
if not Crep then
|
Apply_Discriminant_Check (Rhs, Etype (Lhs));
|
Apply_Discriminant_Check (Rhs, Etype (Lhs));
|
end if;
|
end if;
|
|
|
elsif Is_Array_Type (Designated_Type (Etype (Lhs))) then
|
elsif Is_Array_Type (Designated_Type (Etype (Lhs))) then
|
Apply_Range_Check (Rhs, Etype (Lhs));
|
Apply_Range_Check (Rhs, Etype (Lhs));
|
|
|
if Is_Constrained (Etype (Lhs)) then
|
if Is_Constrained (Etype (Lhs)) then
|
Apply_Length_Check (Rhs, Etype (Lhs));
|
Apply_Length_Check (Rhs, Etype (Lhs));
|
end if;
|
end if;
|
|
|
if Nkind (Rhs) = N_Allocator then
|
if Nkind (Rhs) = N_Allocator then
|
declare
|
declare
|
Target_Typ : constant Entity_Id := Etype (Expression (Rhs));
|
Target_Typ : constant Entity_Id := Etype (Expression (Rhs));
|
C_Es : Check_Result;
|
C_Es : Check_Result;
|
|
|
begin
|
begin
|
C_Es :=
|
C_Es :=
|
Get_Range_Checks
|
Get_Range_Checks
|
(Lhs,
|
(Lhs,
|
Target_Typ,
|
Target_Typ,
|
Etype (Designated_Type (Etype (Lhs))));
|
Etype (Designated_Type (Etype (Lhs))));
|
|
|
Insert_Range_Checks
|
Insert_Range_Checks
|
(C_Es,
|
(C_Es,
|
N,
|
N,
|
Target_Typ,
|
Target_Typ,
|
Sloc (Lhs),
|
Sloc (Lhs),
|
Lhs);
|
Lhs);
|
end;
|
end;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- Apply range check for access type case
|
-- Apply range check for access type case
|
|
|
elsif Is_Access_Type (Etype (Lhs))
|
elsif Is_Access_Type (Etype (Lhs))
|
and then Nkind (Rhs) = N_Allocator
|
and then Nkind (Rhs) = N_Allocator
|
and then Nkind (Expression (Rhs)) = N_Qualified_Expression
|
and then Nkind (Expression (Rhs)) = N_Qualified_Expression
|
then
|
then
|
Analyze_And_Resolve (Expression (Rhs));
|
Analyze_And_Resolve (Expression (Rhs));
|
Apply_Range_Check
|
Apply_Range_Check
|
(Expression (Rhs), Designated_Type (Etype (Lhs)));
|
(Expression (Rhs), Designated_Type (Etype (Lhs)));
|
end if;
|
end if;
|
|
|
-- Ada 2005 (AI-231): Generate the run-time check
|
-- Ada 2005 (AI-231): Generate the run-time check
|
|
|
if Is_Access_Type (Typ)
|
if Is_Access_Type (Typ)
|
and then Can_Never_Be_Null (Etype (Lhs))
|
and then Can_Never_Be_Null (Etype (Lhs))
|
and then not Can_Never_Be_Null (Etype (Rhs))
|
and then not Can_Never_Be_Null (Etype (Rhs))
|
then
|
then
|
Apply_Constraint_Check (Rhs, Etype (Lhs));
|
Apply_Constraint_Check (Rhs, Etype (Lhs));
|
end if;
|
end if;
|
|
|
-- Ada 2012 (AI05-148): Update current accessibility level if Rhs is a
|
-- Ada 2012 (AI05-148): Update current accessibility level if Rhs is a
|
-- stand-alone obj of an anonymous access type.
|
-- stand-alone obj of an anonymous access type.
|
|
|
if Is_Access_Type (Typ)
|
if Is_Access_Type (Typ)
|
and then Is_Entity_Name (Lhs)
|
and then Is_Entity_Name (Lhs)
|
and then Present (Effective_Extra_Accessibility (Entity (Lhs))) then
|
and then Present (Effective_Extra_Accessibility (Entity (Lhs))) then
|
declare
|
declare
|
function Lhs_Entity return Entity_Id;
|
function Lhs_Entity return Entity_Id;
|
-- Look through renames to find the underlying entity.
|
-- Look through renames to find the underlying entity.
|
-- For assignment to a rename, we don't care about the
|
-- For assignment to a rename, we don't care about the
|
-- Enclosing_Dynamic_Scope of the rename declaration.
|
-- Enclosing_Dynamic_Scope of the rename declaration.
|
|
|
----------------
|
----------------
|
-- Lhs_Entity --
|
-- Lhs_Entity --
|
----------------
|
----------------
|
|
|
function Lhs_Entity return Entity_Id is
|
function Lhs_Entity return Entity_Id is
|
Result : Entity_Id := Entity (Lhs);
|
Result : Entity_Id := Entity (Lhs);
|
|
|
begin
|
begin
|
while Present (Renamed_Object (Result)) loop
|
while Present (Renamed_Object (Result)) loop
|
|
|
-- Renamed_Object must return an Entity_Name here
|
-- Renamed_Object must return an Entity_Name here
|
-- because of preceding "Present (E_E_A (...))" test.
|
-- because of preceding "Present (E_E_A (...))" test.
|
|
|
Result := Entity (Renamed_Object (Result));
|
Result := Entity (Renamed_Object (Result));
|
end loop;
|
end loop;
|
|
|
return Result;
|
return Result;
|
end Lhs_Entity;
|
end Lhs_Entity;
|
|
|
-- Local Declarations
|
-- Local Declarations
|
|
|
Access_Check : constant Node_Id :=
|
Access_Check : constant Node_Id :=
|
Make_Raise_Program_Error (Loc,
|
Make_Raise_Program_Error (Loc,
|
Condition =>
|
Condition =>
|
Make_Op_Gt (Loc,
|
Make_Op_Gt (Loc,
|
Left_Opnd =>
|
Left_Opnd =>
|
Dynamic_Accessibility_Level (Rhs),
|
Dynamic_Accessibility_Level (Rhs),
|
Right_Opnd =>
|
Right_Opnd =>
|
Make_Integer_Literal (Loc,
|
Make_Integer_Literal (Loc,
|
Intval =>
|
Intval =>
|
Scope_Depth
|
Scope_Depth
|
(Enclosing_Dynamic_Scope
|
(Enclosing_Dynamic_Scope
|
(Lhs_Entity)))),
|
(Lhs_Entity)))),
|
Reason => PE_Accessibility_Check_Failed);
|
Reason => PE_Accessibility_Check_Failed);
|
|
|
Access_Level_Update : constant Node_Id :=
|
Access_Level_Update : constant Node_Id :=
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name =>
|
Name =>
|
New_Occurrence_Of
|
New_Occurrence_Of
|
(Effective_Extra_Accessibility
|
(Effective_Extra_Accessibility
|
(Entity (Lhs)), Loc),
|
(Entity (Lhs)), Loc),
|
Expression =>
|
Expression =>
|
Dynamic_Accessibility_Level (Rhs));
|
Dynamic_Accessibility_Level (Rhs));
|
|
|
begin
|
begin
|
if not Accessibility_Checks_Suppressed (Entity (Lhs)) then
|
if not Accessibility_Checks_Suppressed (Entity (Lhs)) then
|
Insert_Action (N, Access_Check);
|
Insert_Action (N, Access_Check);
|
end if;
|
end if;
|
|
|
Insert_Action (N, Access_Level_Update);
|
Insert_Action (N, Access_Level_Update);
|
end;
|
end;
|
end if;
|
end if;
|
|
|
-- Case of assignment to a bit packed array element. If there is a
|
-- Case of assignment to a bit packed array element. If there is a
|
-- change of representation this must be expanded into components,
|
-- change of representation this must be expanded into components,
|
-- otherwise this is a bit-field assignment.
|
-- otherwise this is a bit-field assignment.
|
|
|
if Nkind (Lhs) = N_Indexed_Component
|
if Nkind (Lhs) = N_Indexed_Component
|
and then Is_Bit_Packed_Array (Etype (Prefix (Lhs)))
|
and then Is_Bit_Packed_Array (Etype (Prefix (Lhs)))
|
then
|
then
|
-- Normal case, no change of representation
|
-- Normal case, no change of representation
|
|
|
if not Crep then
|
if not Crep then
|
Expand_Bit_Packed_Element_Set (N);
|
Expand_Bit_Packed_Element_Set (N);
|
return;
|
return;
|
|
|
-- Change of representation case
|
-- Change of representation case
|
|
|
else
|
else
|
-- Generate the following, to force component-by-component
|
-- Generate the following, to force component-by-component
|
-- assignments in an efficient way. Otherwise each component
|
-- assignments in an efficient way. Otherwise each component
|
-- will require a temporary and two bit-field manipulations.
|
-- will require a temporary and two bit-field manipulations.
|
|
|
-- T1 : Elmt_Type;
|
-- T1 : Elmt_Type;
|
-- T1 := RhS;
|
-- T1 := RhS;
|
-- Lhs := T1;
|
-- Lhs := T1;
|
|
|
declare
|
declare
|
Tnn : constant Entity_Id := Make_Temporary (Loc, 'T');
|
Tnn : constant Entity_Id := Make_Temporary (Loc, 'T');
|
Stats : List_Id;
|
Stats : List_Id;
|
|
|
begin
|
begin
|
Stats :=
|
Stats :=
|
New_List (
|
New_List (
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Tnn,
|
Defining_Identifier => Tnn,
|
Object_Definition =>
|
Object_Definition =>
|
New_Occurrence_Of (Etype (Lhs), Loc)),
|
New_Occurrence_Of (Etype (Lhs), Loc)),
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => New_Occurrence_Of (Tnn, Loc),
|
Name => New_Occurrence_Of (Tnn, Loc),
|
Expression => Relocate_Node (Rhs)),
|
Expression => Relocate_Node (Rhs)),
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => Relocate_Node (Lhs),
|
Name => Relocate_Node (Lhs),
|
Expression => New_Occurrence_Of (Tnn, Loc)));
|
Expression => New_Occurrence_Of (Tnn, Loc)));
|
|
|
Insert_Actions (N, Stats);
|
Insert_Actions (N, Stats);
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
Analyze (N);
|
Analyze (N);
|
end;
|
end;
|
end if;
|
end if;
|
|
|
-- Build-in-place function call case. Note that we're not yet doing
|
-- Build-in-place function call case. Note that we're not yet doing
|
-- build-in-place for user-written assignment statements (the assignment
|
-- build-in-place for user-written assignment statements (the assignment
|
-- here came from an aggregate.)
|
-- here came from an aggregate.)
|
|
|
elsif Ada_Version >= Ada_2005
|
elsif Ada_Version >= Ada_2005
|
and then Is_Build_In_Place_Function_Call (Rhs)
|
and then Is_Build_In_Place_Function_Call (Rhs)
|
then
|
then
|
Make_Build_In_Place_Call_In_Assignment (N, Rhs);
|
Make_Build_In_Place_Call_In_Assignment (N, Rhs);
|
|
|
elsif Is_Tagged_Type (Typ) and then Is_Value_Type (Etype (Lhs)) then
|
elsif Is_Tagged_Type (Typ) and then Is_Value_Type (Etype (Lhs)) then
|
|
|
-- Nothing to do for valuetypes
|
-- Nothing to do for valuetypes
|
-- ??? Set_Scope_Is_Transient (False);
|
-- ??? Set_Scope_Is_Transient (False);
|
|
|
return;
|
return;
|
|
|
elsif Is_Tagged_Type (Typ)
|
elsif Is_Tagged_Type (Typ)
|
or else (Needs_Finalization (Typ) and then not Is_Array_Type (Typ))
|
or else (Needs_Finalization (Typ) and then not Is_Array_Type (Typ))
|
then
|
then
|
Tagged_Case : declare
|
Tagged_Case : declare
|
L : List_Id := No_List;
|
L : List_Id := No_List;
|
Expand_Ctrl_Actions : constant Boolean := not No_Ctrl_Actions (N);
|
Expand_Ctrl_Actions : constant Boolean := not No_Ctrl_Actions (N);
|
|
|
begin
|
begin
|
-- In the controlled case, we ensure that function calls are
|
-- In the controlled case, we ensure that function calls are
|
-- evaluated before finalizing the target. In all cases, it makes
|
-- evaluated before finalizing the target. In all cases, it makes
|
-- the expansion easier if the side-effects are removed first.
|
-- the expansion easier if the side-effects are removed first.
|
|
|
Remove_Side_Effects (Lhs);
|
Remove_Side_Effects (Lhs);
|
Remove_Side_Effects (Rhs);
|
Remove_Side_Effects (Rhs);
|
|
|
-- Avoid recursion in the mechanism
|
-- Avoid recursion in the mechanism
|
|
|
Set_Analyzed (N);
|
Set_Analyzed (N);
|
|
|
-- If dispatching assignment, we need to dispatch to _assign
|
-- If dispatching assignment, we need to dispatch to _assign
|
|
|
if Is_Class_Wide_Type (Typ)
|
if Is_Class_Wide_Type (Typ)
|
|
|
-- If the type is tagged, we may as well use the predefined
|
-- If the type is tagged, we may as well use the predefined
|
-- primitive assignment. This avoids inlining a lot of code
|
-- primitive assignment. This avoids inlining a lot of code
|
-- and in the class-wide case, the assignment is replaced
|
-- and in the class-wide case, the assignment is replaced
|
-- by a dispatching call to _assign. It is suppressed in the
|
-- by a dispatching call to _assign. It is suppressed in the
|
-- case of assignments created by the expander that correspond
|
-- case of assignments created by the expander that correspond
|
-- to initializations, where we do want to copy the tag
|
-- to initializations, where we do want to copy the tag
|
-- (Expand_Ctrl_Actions flag is set True in this case). It is
|
-- (Expand_Ctrl_Actions flag is set True in this case). It is
|
-- also suppressed if restriction No_Dispatching_Calls is in
|
-- also suppressed if restriction No_Dispatching_Calls is in
|
-- force because in that case predefined primitives are not
|
-- force because in that case predefined primitives are not
|
-- generated.
|
-- generated.
|
|
|
or else (Is_Tagged_Type (Typ)
|
or else (Is_Tagged_Type (Typ)
|
and then not Is_Value_Type (Etype (Lhs))
|
and then not Is_Value_Type (Etype (Lhs))
|
and then Chars (Current_Scope) /= Name_uAssign
|
and then Chars (Current_Scope) /= Name_uAssign
|
and then Expand_Ctrl_Actions
|
and then Expand_Ctrl_Actions
|
and then
|
and then
|
not Restriction_Active (No_Dispatching_Calls))
|
not Restriction_Active (No_Dispatching_Calls))
|
then
|
then
|
if Is_Limited_Type (Typ) then
|
if Is_Limited_Type (Typ) then
|
|
|
-- This can happen in an instance when the formal is an
|
-- This can happen in an instance when the formal is an
|
-- extension of a limited interface, and the actual is
|
-- extension of a limited interface, and the actual is
|
-- limited. This is an error according to AI05-0087, but
|
-- limited. This is an error according to AI05-0087, but
|
-- is not caught at the point of instantiation in earlier
|
-- is not caught at the point of instantiation in earlier
|
-- versions.
|
-- versions.
|
|
|
-- This is wrong, error messages cannot be issued during
|
-- This is wrong, error messages cannot be issued during
|
-- expansion, since they would be missed in -gnatc mode ???
|
-- expansion, since they would be missed in -gnatc mode ???
|
|
|
Error_Msg_N ("assignment not available on limited type", N);
|
Error_Msg_N ("assignment not available on limited type", N);
|
return;
|
return;
|
end if;
|
end if;
|
|
|
-- Fetch the primitive op _assign and proper type to call it.
|
-- Fetch the primitive op _assign and proper type to call it.
|
-- Because of possible conflicts between private and full view,
|
-- Because of possible conflicts between private and full view,
|
-- fetch the proper type directly from the operation profile.
|
-- fetch the proper type directly from the operation profile.
|
|
|
declare
|
declare
|
Op : constant Entity_Id :=
|
Op : constant Entity_Id :=
|
Find_Prim_Op (Typ, Name_uAssign);
|
Find_Prim_Op (Typ, Name_uAssign);
|
F_Typ : Entity_Id := Etype (First_Formal (Op));
|
F_Typ : Entity_Id := Etype (First_Formal (Op));
|
|
|
begin
|
begin
|
-- If the assignment is dispatching, make sure to use the
|
-- If the assignment is dispatching, make sure to use the
|
-- proper type.
|
-- proper type.
|
|
|
if Is_Class_Wide_Type (Typ) then
|
if Is_Class_Wide_Type (Typ) then
|
F_Typ := Class_Wide_Type (F_Typ);
|
F_Typ := Class_Wide_Type (F_Typ);
|
end if;
|
end if;
|
|
|
L := New_List;
|
L := New_List;
|
|
|
-- In case of assignment to a class-wide tagged type, before
|
-- In case of assignment to a class-wide tagged type, before
|
-- the assignment we generate run-time check to ensure that
|
-- the assignment we generate run-time check to ensure that
|
-- the tags of source and target match.
|
-- the tags of source and target match.
|
|
|
if Is_Class_Wide_Type (Typ)
|
if Is_Class_Wide_Type (Typ)
|
and then Is_Tagged_Type (Typ)
|
and then Is_Tagged_Type (Typ)
|
and then Is_Tagged_Type (Underlying_Type (Etype (Rhs)))
|
and then Is_Tagged_Type (Underlying_Type (Etype (Rhs)))
|
then
|
then
|
Append_To (L,
|
Append_To (L,
|
Make_Raise_Constraint_Error (Loc,
|
Make_Raise_Constraint_Error (Loc,
|
Condition =>
|
Condition =>
|
Make_Op_Ne (Loc,
|
Make_Op_Ne (Loc,
|
Left_Opnd =>
|
Left_Opnd =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr (Lhs),
|
Prefix => Duplicate_Subexpr (Lhs),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Name_uTag)),
|
Make_Identifier (Loc, Name_uTag)),
|
Right_Opnd =>
|
Right_Opnd =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr (Rhs),
|
Prefix => Duplicate_Subexpr (Rhs),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Name_uTag))),
|
Make_Identifier (Loc, Name_uTag))),
|
Reason => CE_Tag_Check_Failed));
|
Reason => CE_Tag_Check_Failed));
|
end if;
|
end if;
|
|
|
declare
|
declare
|
Left_N : Node_Id := Duplicate_Subexpr (Lhs);
|
Left_N : Node_Id := Duplicate_Subexpr (Lhs);
|
Right_N : Node_Id := Duplicate_Subexpr (Rhs);
|
Right_N : Node_Id := Duplicate_Subexpr (Rhs);
|
|
|
begin
|
begin
|
-- In order to dispatch the call to _assign the type of
|
-- In order to dispatch the call to _assign the type of
|
-- the actuals must match. Add conversion (if required).
|
-- the actuals must match. Add conversion (if required).
|
|
|
if Etype (Lhs) /= F_Typ then
|
if Etype (Lhs) /= F_Typ then
|
Left_N := Unchecked_Convert_To (F_Typ, Left_N);
|
Left_N := Unchecked_Convert_To (F_Typ, Left_N);
|
end if;
|
end if;
|
|
|
if Etype (Rhs) /= F_Typ then
|
if Etype (Rhs) /= F_Typ then
|
Right_N := Unchecked_Convert_To (F_Typ, Right_N);
|
Right_N := Unchecked_Convert_To (F_Typ, Right_N);
|
end if;
|
end if;
|
|
|
Append_To (L,
|
Append_To (L,
|
Make_Procedure_Call_Statement (Loc,
|
Make_Procedure_Call_Statement (Loc,
|
Name => New_Reference_To (Op, Loc),
|
Name => New_Reference_To (Op, Loc),
|
Parameter_Associations => New_List (
|
Parameter_Associations => New_List (
|
Node1 => Left_N,
|
Node1 => Left_N,
|
Node2 => Right_N)));
|
Node2 => Right_N)));
|
end;
|
end;
|
end;
|
end;
|
|
|
else
|
else
|
L := Make_Tag_Ctrl_Assignment (N);
|
L := Make_Tag_Ctrl_Assignment (N);
|
|
|
-- We can't afford to have destructive Finalization Actions in
|
-- We can't afford to have destructive Finalization Actions in
|
-- the Self assignment case, so if the target and the source
|
-- the Self assignment case, so if the target and the source
|
-- are not obviously different, code is generated to avoid the
|
-- are not obviously different, code is generated to avoid the
|
-- self assignment case:
|
-- self assignment case:
|
|
|
-- if lhs'address /= rhs'address then
|
-- if lhs'address /= rhs'address then
|
-- <code for controlled and/or tagged assignment>
|
-- <code for controlled and/or tagged assignment>
|
-- end if;
|
-- end if;
|
|
|
-- Skip this if Restriction (No_Finalization) is active
|
-- Skip this if Restriction (No_Finalization) is active
|
|
|
if not Statically_Different (Lhs, Rhs)
|
if not Statically_Different (Lhs, Rhs)
|
and then Expand_Ctrl_Actions
|
and then Expand_Ctrl_Actions
|
and then not Restriction_Active (No_Finalization)
|
and then not Restriction_Active (No_Finalization)
|
then
|
then
|
L := New_List (
|
L := New_List (
|
Make_Implicit_If_Statement (N,
|
Make_Implicit_If_Statement (N,
|
Condition =>
|
Condition =>
|
Make_Op_Ne (Loc,
|
Make_Op_Ne (Loc,
|
Left_Opnd =>
|
Left_Opnd =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix => Duplicate_Subexpr (Lhs),
|
Prefix => Duplicate_Subexpr (Lhs),
|
Attribute_Name => Name_Address),
|
Attribute_Name => Name_Address),
|
|
|
Right_Opnd =>
|
Right_Opnd =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix => Duplicate_Subexpr (Rhs),
|
Prefix => Duplicate_Subexpr (Rhs),
|
Attribute_Name => Name_Address)),
|
Attribute_Name => Name_Address)),
|
|
|
Then_Statements => L));
|
Then_Statements => L));
|
end if;
|
end if;
|
|
|
-- We need to set up an exception handler for implementing
|
-- We need to set up an exception handler for implementing
|
-- 7.6.1(18). The remaining adjustments are tackled by the
|
-- 7.6.1(18). The remaining adjustments are tackled by the
|
-- implementation of adjust for record_controllers (see
|
-- implementation of adjust for record_controllers (see
|
-- s-finimp.adb).
|
-- s-finimp.adb).
|
|
|
-- This is skipped if we have no finalization
|
-- This is skipped if we have no finalization
|
|
|
if Expand_Ctrl_Actions
|
if Expand_Ctrl_Actions
|
and then not Restriction_Active (No_Finalization)
|
and then not Restriction_Active (No_Finalization)
|
then
|
then
|
L := New_List (
|
L := New_List (
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Statements => L,
|
Statements => L,
|
Exception_Handlers => New_List (
|
Exception_Handlers => New_List (
|
Make_Handler_For_Ctrl_Operation (Loc)))));
|
Make_Handler_For_Ctrl_Operation (Loc)))));
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc, Statements => L)));
|
Make_Handled_Sequence_Of_Statements (Loc, Statements => L)));
|
|
|
-- If no restrictions on aborts, protect the whole assignment
|
-- If no restrictions on aborts, protect the whole assignment
|
-- for controlled objects as per 9.8(11).
|
-- for controlled objects as per 9.8(11).
|
|
|
if Needs_Finalization (Typ)
|
if Needs_Finalization (Typ)
|
and then Expand_Ctrl_Actions
|
and then Expand_Ctrl_Actions
|
and then Abort_Allowed
|
and then Abort_Allowed
|
then
|
then
|
declare
|
declare
|
Blk : constant Entity_Id :=
|
Blk : constant Entity_Id :=
|
New_Internal_Entity
|
New_Internal_Entity
|
(E_Block, Current_Scope, Sloc (N), 'B');
|
(E_Block, Current_Scope, Sloc (N), 'B');
|
|
|
begin
|
begin
|
Set_Scope (Blk, Current_Scope);
|
Set_Scope (Blk, Current_Scope);
|
Set_Etype (Blk, Standard_Void_Type);
|
Set_Etype (Blk, Standard_Void_Type);
|
Set_Identifier (N, New_Occurrence_Of (Blk, Sloc (N)));
|
Set_Identifier (N, New_Occurrence_Of (Blk, Sloc (N)));
|
|
|
Prepend_To (L, Build_Runtime_Call (Loc, RE_Abort_Defer));
|
Prepend_To (L, Build_Runtime_Call (Loc, RE_Abort_Defer));
|
Set_At_End_Proc (Handled_Statement_Sequence (N),
|
Set_At_End_Proc (Handled_Statement_Sequence (N),
|
New_Occurrence_Of (RTE (RE_Abort_Undefer_Direct), Loc));
|
New_Occurrence_Of (RTE (RE_Abort_Undefer_Direct), Loc));
|
Expand_At_End_Handler
|
Expand_At_End_Handler
|
(Handled_Statement_Sequence (N), Blk);
|
(Handled_Statement_Sequence (N), Blk);
|
end;
|
end;
|
end if;
|
end if;
|
|
|
-- N has been rewritten to a block statement for which it is
|
-- N has been rewritten to a block statement for which it is
|
-- known by construction that no checks are necessary: analyze
|
-- known by construction that no checks are necessary: analyze
|
-- it with all checks suppressed.
|
-- it with all checks suppressed.
|
|
|
Analyze (N, Suppress => All_Checks);
|
Analyze (N, Suppress => All_Checks);
|
return;
|
return;
|
end Tagged_Case;
|
end Tagged_Case;
|
|
|
-- Array types
|
-- Array types
|
|
|
elsif Is_Array_Type (Typ) then
|
elsif Is_Array_Type (Typ) then
|
declare
|
declare
|
Actual_Rhs : Node_Id := Rhs;
|
Actual_Rhs : Node_Id := Rhs;
|
|
|
begin
|
begin
|
while Nkind_In (Actual_Rhs, N_Type_Conversion,
|
while Nkind_In (Actual_Rhs, N_Type_Conversion,
|
N_Qualified_Expression)
|
N_Qualified_Expression)
|
loop
|
loop
|
Actual_Rhs := Expression (Actual_Rhs);
|
Actual_Rhs := Expression (Actual_Rhs);
|
end loop;
|
end loop;
|
|
|
Expand_Assign_Array (N, Actual_Rhs);
|
Expand_Assign_Array (N, Actual_Rhs);
|
return;
|
return;
|
end;
|
end;
|
|
|
-- Record types
|
-- Record types
|
|
|
elsif Is_Record_Type (Typ) then
|
elsif Is_Record_Type (Typ) then
|
Expand_Assign_Record (N);
|
Expand_Assign_Record (N);
|
return;
|
return;
|
|
|
-- Scalar types. This is where we perform the processing related to the
|
-- Scalar types. This is where we perform the processing related to the
|
-- requirements of (RM 13.9.1(9-11)) concerning the handling of invalid
|
-- requirements of (RM 13.9.1(9-11)) concerning the handling of invalid
|
-- scalar values.
|
-- scalar values.
|
|
|
elsif Is_Scalar_Type (Typ) then
|
elsif Is_Scalar_Type (Typ) then
|
|
|
-- Case where right side is known valid
|
-- Case where right side is known valid
|
|
|
if Expr_Known_Valid (Rhs) then
|
if Expr_Known_Valid (Rhs) then
|
|
|
-- Here the right side is valid, so it is fine. The case to deal
|
-- Here the right side is valid, so it is fine. The case to deal
|
-- with is when the left side is a local variable reference whose
|
-- with is when the left side is a local variable reference whose
|
-- value is not currently known to be valid. If this is the case,
|
-- value is not currently known to be valid. If this is the case,
|
-- and the assignment appears in an unconditional context, then
|
-- and the assignment appears in an unconditional context, then
|
-- we can mark the left side as now being valid if one of these
|
-- we can mark the left side as now being valid if one of these
|
-- conditions holds:
|
-- conditions holds:
|
|
|
-- The expression of the right side has Do_Range_Check set so
|
-- The expression of the right side has Do_Range_Check set so
|
-- that we know a range check will be performed. Note that it
|
-- that we know a range check will be performed. Note that it
|
-- can be the case that a range check is omitted because we
|
-- can be the case that a range check is omitted because we
|
-- make the assumption that we can assume validity for operands
|
-- make the assumption that we can assume validity for operands
|
-- appearing in the right side in determining whether a range
|
-- appearing in the right side in determining whether a range
|
-- check is required
|
-- check is required
|
|
|
-- The subtype of the right side matches the subtype of the
|
-- The subtype of the right side matches the subtype of the
|
-- left side. In this case, even though we have not checked
|
-- left side. In this case, even though we have not checked
|
-- the range of the right side, we know it is in range of its
|
-- the range of the right side, we know it is in range of its
|
-- subtype if the expression is valid.
|
-- subtype if the expression is valid.
|
|
|
if Is_Local_Variable_Reference (Lhs)
|
if Is_Local_Variable_Reference (Lhs)
|
and then not Is_Known_Valid (Entity (Lhs))
|
and then not Is_Known_Valid (Entity (Lhs))
|
and then In_Unconditional_Context (N)
|
and then In_Unconditional_Context (N)
|
then
|
then
|
if Do_Range_Check (Rhs)
|
if Do_Range_Check (Rhs)
|
or else Etype (Lhs) = Etype (Rhs)
|
or else Etype (Lhs) = Etype (Rhs)
|
then
|
then
|
Set_Is_Known_Valid (Entity (Lhs), True);
|
Set_Is_Known_Valid (Entity (Lhs), True);
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- Case where right side may be invalid in the sense of the RM
|
-- Case where right side may be invalid in the sense of the RM
|
-- reference above. The RM does not require that we check for the
|
-- reference above. The RM does not require that we check for the
|
-- validity on an assignment, but it does require that the assignment
|
-- validity on an assignment, but it does require that the assignment
|
-- of an invalid value not cause erroneous behavior.
|
-- of an invalid value not cause erroneous behavior.
|
|
|
-- The general approach in GNAT is to use the Is_Known_Valid flag
|
-- The general approach in GNAT is to use the Is_Known_Valid flag
|
-- to avoid the need for validity checking on assignments. However
|
-- to avoid the need for validity checking on assignments. However
|
-- in some cases, we have to do validity checking in order to make
|
-- in some cases, we have to do validity checking in order to make
|
-- sure that the setting of this flag is correct.
|
-- sure that the setting of this flag is correct.
|
|
|
else
|
else
|
-- Validate right side if we are validating copies
|
-- Validate right side if we are validating copies
|
|
|
if Validity_Checks_On
|
if Validity_Checks_On
|
and then Validity_Check_Copies
|
and then Validity_Check_Copies
|
then
|
then
|
-- Skip this if left hand side is an array or record component
|
-- Skip this if left hand side is an array or record component
|
-- and elementary component validity checks are suppressed.
|
-- and elementary component validity checks are suppressed.
|
|
|
if Nkind_In (Lhs, N_Selected_Component, N_Indexed_Component)
|
if Nkind_In (Lhs, N_Selected_Component, N_Indexed_Component)
|
and then not Validity_Check_Components
|
and then not Validity_Check_Components
|
then
|
then
|
null;
|
null;
|
else
|
else
|
Ensure_Valid (Rhs);
|
Ensure_Valid (Rhs);
|
end if;
|
end if;
|
|
|
-- We can propagate this to the left side where appropriate
|
-- We can propagate this to the left side where appropriate
|
|
|
if Is_Local_Variable_Reference (Lhs)
|
if Is_Local_Variable_Reference (Lhs)
|
and then not Is_Known_Valid (Entity (Lhs))
|
and then not Is_Known_Valid (Entity (Lhs))
|
and then In_Unconditional_Context (N)
|
and then In_Unconditional_Context (N)
|
then
|
then
|
Set_Is_Known_Valid (Entity (Lhs), True);
|
Set_Is_Known_Valid (Entity (Lhs), True);
|
end if;
|
end if;
|
|
|
-- Otherwise check to see what should be done
|
-- Otherwise check to see what should be done
|
|
|
-- If left side is a local variable, then we just set its flag to
|
-- If left side is a local variable, then we just set its flag to
|
-- indicate that its value may no longer be valid, since we are
|
-- indicate that its value may no longer be valid, since we are
|
-- copying a potentially invalid value.
|
-- copying a potentially invalid value.
|
|
|
elsif Is_Local_Variable_Reference (Lhs) then
|
elsif Is_Local_Variable_Reference (Lhs) then
|
Set_Is_Known_Valid (Entity (Lhs), False);
|
Set_Is_Known_Valid (Entity (Lhs), False);
|
|
|
-- Check for case of a nonlocal variable on the left side which
|
-- Check for case of a nonlocal variable on the left side which
|
-- is currently known to be valid. In this case, we simply ensure
|
-- is currently known to be valid. In this case, we simply ensure
|
-- that the right side is valid. We only play the game of copying
|
-- that the right side is valid. We only play the game of copying
|
-- validity status for local variables, since we are doing this
|
-- validity status for local variables, since we are doing this
|
-- statically, not by tracing the full flow graph.
|
-- statically, not by tracing the full flow graph.
|
|
|
elsif Is_Entity_Name (Lhs)
|
elsif Is_Entity_Name (Lhs)
|
and then Is_Known_Valid (Entity (Lhs))
|
and then Is_Known_Valid (Entity (Lhs))
|
then
|
then
|
-- Note: If Validity_Checking mode is set to none, we ignore
|
-- Note: If Validity_Checking mode is set to none, we ignore
|
-- the Ensure_Valid call so don't worry about that case here.
|
-- the Ensure_Valid call so don't worry about that case here.
|
|
|
Ensure_Valid (Rhs);
|
Ensure_Valid (Rhs);
|
|
|
-- In all other cases, we can safely copy an invalid value without
|
-- In all other cases, we can safely copy an invalid value without
|
-- worrying about the status of the left side. Since it is not a
|
-- worrying about the status of the left side. Since it is not a
|
-- variable reference it will not be considered
|
-- variable reference it will not be considered
|
-- as being known to be valid in any case.
|
-- as being known to be valid in any case.
|
|
|
else
|
else
|
null;
|
null;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
exception
|
exception
|
when RE_Not_Available =>
|
when RE_Not_Available =>
|
return;
|
return;
|
end Expand_N_Assignment_Statement;
|
end Expand_N_Assignment_Statement;
|
|
|
------------------------------
|
------------------------------
|
-- Expand_N_Block_Statement --
|
-- Expand_N_Block_Statement --
|
------------------------------
|
------------------------------
|
|
|
-- Encode entity names defined in block statement
|
-- Encode entity names defined in block statement
|
|
|
procedure Expand_N_Block_Statement (N : Node_Id) is
|
procedure Expand_N_Block_Statement (N : Node_Id) is
|
begin
|
begin
|
Qualify_Entity_Names (N);
|
Qualify_Entity_Names (N);
|
end Expand_N_Block_Statement;
|
end Expand_N_Block_Statement;
|
|
|
-----------------------------
|
-----------------------------
|
-- Expand_N_Case_Statement --
|
-- Expand_N_Case_Statement --
|
-----------------------------
|
-----------------------------
|
|
|
procedure Expand_N_Case_Statement (N : Node_Id) is
|
procedure Expand_N_Case_Statement (N : Node_Id) is
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Expr : constant Node_Id := Expression (N);
|
Expr : constant Node_Id := Expression (N);
|
Alt : Node_Id;
|
Alt : Node_Id;
|
Len : Nat;
|
Len : Nat;
|
Cond : Node_Id;
|
Cond : Node_Id;
|
Choice : Node_Id;
|
Choice : Node_Id;
|
Chlist : List_Id;
|
Chlist : List_Id;
|
|
|
begin
|
begin
|
-- Check for the situation where we know at compile time which branch
|
-- Check for the situation where we know at compile time which branch
|
-- will be taken
|
-- will be taken
|
|
|
if Compile_Time_Known_Value (Expr) then
|
if Compile_Time_Known_Value (Expr) then
|
Alt := Find_Static_Alternative (N);
|
Alt := Find_Static_Alternative (N);
|
|
|
Process_Statements_For_Controlled_Objects (Alt);
|
Process_Statements_For_Controlled_Objects (Alt);
|
|
|
-- Move statements from this alternative after the case statement.
|
-- Move statements from this alternative after the case statement.
|
-- They are already analyzed, so will be skipped by the analyzer.
|
-- They are already analyzed, so will be skipped by the analyzer.
|
|
|
Insert_List_After (N, Statements (Alt));
|
Insert_List_After (N, Statements (Alt));
|
|
|
-- That leaves the case statement as a shell. So now we can kill all
|
-- That leaves the case statement as a shell. So now we can kill all
|
-- other alternatives in the case statement.
|
-- other alternatives in the case statement.
|
|
|
Kill_Dead_Code (Expression (N));
|
Kill_Dead_Code (Expression (N));
|
|
|
declare
|
declare
|
Dead_Alt : Node_Id;
|
Dead_Alt : Node_Id;
|
|
|
begin
|
begin
|
-- Loop through case alternatives, skipping pragmas, and skipping
|
-- Loop through case alternatives, skipping pragmas, and skipping
|
-- the one alternative that we select (and therefore retain).
|
-- the one alternative that we select (and therefore retain).
|
|
|
Dead_Alt := First (Alternatives (N));
|
Dead_Alt := First (Alternatives (N));
|
while Present (Dead_Alt) loop
|
while Present (Dead_Alt) loop
|
if Dead_Alt /= Alt
|
if Dead_Alt /= Alt
|
and then Nkind (Dead_Alt) = N_Case_Statement_Alternative
|
and then Nkind (Dead_Alt) = N_Case_Statement_Alternative
|
then
|
then
|
Kill_Dead_Code (Statements (Dead_Alt), Warn_On_Deleted_Code);
|
Kill_Dead_Code (Statements (Dead_Alt), Warn_On_Deleted_Code);
|
end if;
|
end if;
|
|
|
Next (Dead_Alt);
|
Next (Dead_Alt);
|
end loop;
|
end loop;
|
end;
|
end;
|
|
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
return;
|
return;
|
end if;
|
end if;
|
|
|
-- Here if the choice is not determined at compile time
|
-- Here if the choice is not determined at compile time
|
|
|
declare
|
declare
|
Last_Alt : constant Node_Id := Last (Alternatives (N));
|
Last_Alt : constant Node_Id := Last (Alternatives (N));
|
|
|
Others_Present : Boolean;
|
Others_Present : Boolean;
|
Others_Node : Node_Id;
|
Others_Node : Node_Id;
|
|
|
Then_Stms : List_Id;
|
Then_Stms : List_Id;
|
Else_Stms : List_Id;
|
Else_Stms : List_Id;
|
|
|
begin
|
begin
|
if Nkind (First (Discrete_Choices (Last_Alt))) = N_Others_Choice then
|
if Nkind (First (Discrete_Choices (Last_Alt))) = N_Others_Choice then
|
Others_Present := True;
|
Others_Present := True;
|
Others_Node := Last_Alt;
|
Others_Node := Last_Alt;
|
else
|
else
|
Others_Present := False;
|
Others_Present := False;
|
end if;
|
end if;
|
|
|
-- First step is to worry about possible invalid argument. The RM
|
-- First step is to worry about possible invalid argument. The RM
|
-- requires (RM 5.4(13)) that if the result is invalid (e.g. it is
|
-- requires (RM 5.4(13)) that if the result is invalid (e.g. it is
|
-- outside the base range), then Constraint_Error must be raised.
|
-- outside the base range), then Constraint_Error must be raised.
|
|
|
-- Case of validity check required (validity checks are on, the
|
-- Case of validity check required (validity checks are on, the
|
-- expression is not known to be valid, and the case statement
|
-- expression is not known to be valid, and the case statement
|
-- comes from source -- no need to validity check internally
|
-- comes from source -- no need to validity check internally
|
-- generated case statements).
|
-- generated case statements).
|
|
|
if Validity_Check_Default then
|
if Validity_Check_Default then
|
Ensure_Valid (Expr);
|
Ensure_Valid (Expr);
|
end if;
|
end if;
|
|
|
-- If there is only a single alternative, just replace it with the
|
-- If there is only a single alternative, just replace it with the
|
-- sequence of statements since obviously that is what is going to
|
-- sequence of statements since obviously that is what is going to
|
-- be executed in all cases.
|
-- be executed in all cases.
|
|
|
Len := List_Length (Alternatives (N));
|
Len := List_Length (Alternatives (N));
|
|
|
if Len = 1 then
|
if Len = 1 then
|
|
|
-- We still need to evaluate the expression if it has any side
|
-- We still need to evaluate the expression if it has any side
|
-- effects.
|
-- effects.
|
|
|
Remove_Side_Effects (Expression (N));
|
Remove_Side_Effects (Expression (N));
|
|
|
Alt := First (Alternatives (N));
|
Alt := First (Alternatives (N));
|
|
|
Process_Statements_For_Controlled_Objects (Alt);
|
Process_Statements_For_Controlled_Objects (Alt);
|
Insert_List_After (N, Statements (Alt));
|
Insert_List_After (N, Statements (Alt));
|
|
|
-- That leaves the case statement as a shell. The alternative that
|
-- That leaves the case statement as a shell. The alternative that
|
-- will be executed is reset to a null list. So now we can kill
|
-- will be executed is reset to a null list. So now we can kill
|
-- the entire case statement.
|
-- the entire case statement.
|
|
|
Kill_Dead_Code (Expression (N));
|
Kill_Dead_Code (Expression (N));
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
return;
|
return;
|
|
|
-- An optimization. If there are only two alternatives, and only
|
-- An optimization. If there are only two alternatives, and only
|
-- a single choice, then rewrite the whole case statement as an
|
-- a single choice, then rewrite the whole case statement as an
|
-- if statement, since this can result in subsequent optimizations.
|
-- if statement, since this can result in subsequent optimizations.
|
-- This helps not only with case statements in the source of a
|
-- This helps not only with case statements in the source of a
|
-- simple form, but also with generated code (discriminant check
|
-- simple form, but also with generated code (discriminant check
|
-- functions in particular)
|
-- functions in particular)
|
|
|
elsif Len = 2 then
|
elsif Len = 2 then
|
Chlist := Discrete_Choices (First (Alternatives (N)));
|
Chlist := Discrete_Choices (First (Alternatives (N)));
|
|
|
if List_Length (Chlist) = 1 then
|
if List_Length (Chlist) = 1 then
|
Choice := First (Chlist);
|
Choice := First (Chlist);
|
|
|
Then_Stms := Statements (First (Alternatives (N)));
|
Then_Stms := Statements (First (Alternatives (N)));
|
Else_Stms := Statements (Last (Alternatives (N)));
|
Else_Stms := Statements (Last (Alternatives (N)));
|
|
|
-- For TRUE, generate "expression", not expression = true
|
-- For TRUE, generate "expression", not expression = true
|
|
|
if Nkind (Choice) = N_Identifier
|
if Nkind (Choice) = N_Identifier
|
and then Entity (Choice) = Standard_True
|
and then Entity (Choice) = Standard_True
|
then
|
then
|
Cond := Expression (N);
|
Cond := Expression (N);
|
|
|
-- For FALSE, generate "expression" and switch then/else
|
-- For FALSE, generate "expression" and switch then/else
|
|
|
elsif Nkind (Choice) = N_Identifier
|
elsif Nkind (Choice) = N_Identifier
|
and then Entity (Choice) = Standard_False
|
and then Entity (Choice) = Standard_False
|
then
|
then
|
Cond := Expression (N);
|
Cond := Expression (N);
|
Else_Stms := Statements (First (Alternatives (N)));
|
Else_Stms := Statements (First (Alternatives (N)));
|
Then_Stms := Statements (Last (Alternatives (N)));
|
Then_Stms := Statements (Last (Alternatives (N)));
|
|
|
-- For a range, generate "expression in range"
|
-- For a range, generate "expression in range"
|
|
|
elsif Nkind (Choice) = N_Range
|
elsif Nkind (Choice) = N_Range
|
or else (Nkind (Choice) = N_Attribute_Reference
|
or else (Nkind (Choice) = N_Attribute_Reference
|
and then Attribute_Name (Choice) = Name_Range)
|
and then Attribute_Name (Choice) = Name_Range)
|
or else (Is_Entity_Name (Choice)
|
or else (Is_Entity_Name (Choice)
|
and then Is_Type (Entity (Choice)))
|
and then Is_Type (Entity (Choice)))
|
or else Nkind (Choice) = N_Subtype_Indication
|
or else Nkind (Choice) = N_Subtype_Indication
|
then
|
then
|
Cond :=
|
Cond :=
|
Make_In (Loc,
|
Make_In (Loc,
|
Left_Opnd => Expression (N),
|
Left_Opnd => Expression (N),
|
Right_Opnd => Relocate_Node (Choice));
|
Right_Opnd => Relocate_Node (Choice));
|
|
|
-- For any other subexpression "expression = value"
|
-- For any other subexpression "expression = value"
|
|
|
else
|
else
|
Cond :=
|
Cond :=
|
Make_Op_Eq (Loc,
|
Make_Op_Eq (Loc,
|
Left_Opnd => Expression (N),
|
Left_Opnd => Expression (N),
|
Right_Opnd => Relocate_Node (Choice));
|
Right_Opnd => Relocate_Node (Choice));
|
end if;
|
end if;
|
|
|
-- Now rewrite the case as an IF
|
-- Now rewrite the case as an IF
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_If_Statement (Loc,
|
Make_If_Statement (Loc,
|
Condition => Cond,
|
Condition => Cond,
|
Then_Statements => Then_Stms,
|
Then_Statements => Then_Stms,
|
Else_Statements => Else_Stms));
|
Else_Statements => Else_Stms));
|
Analyze (N);
|
Analyze (N);
|
return;
|
return;
|
end if;
|
end if;
|
end if;
|
end if;
|
|
|
-- If the last alternative is not an Others choice, replace it with
|
-- If the last alternative is not an Others choice, replace it with
|
-- an N_Others_Choice. Note that we do not bother to call Analyze on
|
-- an N_Others_Choice. Note that we do not bother to call Analyze on
|
-- the modified case statement, since it's only effect would be to
|
-- the modified case statement, since it's only effect would be to
|
-- compute the contents of the Others_Discrete_Choices which is not
|
-- compute the contents of the Others_Discrete_Choices which is not
|
-- needed by the back end anyway.
|
-- needed by the back end anyway.
|
|
|
-- The reason we do this is that the back end always needs some
|
-- The reason we do this is that the back end always needs some
|
-- default for a switch, so if we have not supplied one in the
|
-- default for a switch, so if we have not supplied one in the
|
-- processing above for validity checking, then we need to supply
|
-- processing above for validity checking, then we need to supply
|
-- one here.
|
-- one here.
|
|
|
if not Others_Present then
|
if not Others_Present then
|
Others_Node := Make_Others_Choice (Sloc (Last_Alt));
|
Others_Node := Make_Others_Choice (Sloc (Last_Alt));
|
Set_Others_Discrete_Choices
|
Set_Others_Discrete_Choices
|
(Others_Node, Discrete_Choices (Last_Alt));
|
(Others_Node, Discrete_Choices (Last_Alt));
|
Set_Discrete_Choices (Last_Alt, New_List (Others_Node));
|
Set_Discrete_Choices (Last_Alt, New_List (Others_Node));
|
end if;
|
end if;
|
|
|
Alt := First (Alternatives (N));
|
Alt := First (Alternatives (N));
|
while Present (Alt)
|
while Present (Alt)
|
and then Nkind (Alt) = N_Case_Statement_Alternative
|
and then Nkind (Alt) = N_Case_Statement_Alternative
|
loop
|
loop
|
Process_Statements_For_Controlled_Objects (Alt);
|
Process_Statements_For_Controlled_Objects (Alt);
|
Next (Alt);
|
Next (Alt);
|
end loop;
|
end loop;
|
end;
|
end;
|
end Expand_N_Case_Statement;
|
end Expand_N_Case_Statement;
|
|
|
-----------------------------
|
-----------------------------
|
-- Expand_N_Exit_Statement --
|
-- Expand_N_Exit_Statement --
|
-----------------------------
|
-----------------------------
|
|
|
-- The only processing required is to deal with a possible C/Fortran
|
-- The only processing required is to deal with a possible C/Fortran
|
-- boolean value used as the condition for the exit statement.
|
-- boolean value used as the condition for the exit statement.
|
|
|
procedure Expand_N_Exit_Statement (N : Node_Id) is
|
procedure Expand_N_Exit_Statement (N : Node_Id) is
|
begin
|
begin
|
Adjust_Condition (Condition (N));
|
Adjust_Condition (Condition (N));
|
end Expand_N_Exit_Statement;
|
end Expand_N_Exit_Statement;
|
|
|
-----------------------------
|
-----------------------------
|
-- Expand_N_Goto_Statement --
|
-- Expand_N_Goto_Statement --
|
-----------------------------
|
-----------------------------
|
|
|
-- Add poll before goto if polling active
|
-- Add poll before goto if polling active
|
|
|
procedure Expand_N_Goto_Statement (N : Node_Id) is
|
procedure Expand_N_Goto_Statement (N : Node_Id) is
|
begin
|
begin
|
Generate_Poll_Call (N);
|
Generate_Poll_Call (N);
|
end Expand_N_Goto_Statement;
|
end Expand_N_Goto_Statement;
|
|
|
---------------------------
|
---------------------------
|
-- Expand_N_If_Statement --
|
-- Expand_N_If_Statement --
|
---------------------------
|
---------------------------
|
|
|
-- First we deal with the case of C and Fortran convention boolean values,
|
-- First we deal with the case of C and Fortran convention boolean values,
|
-- with zero/non-zero semantics.
|
-- with zero/non-zero semantics.
|
|
|
-- Second, we deal with the obvious rewriting for the cases where the
|
-- Second, we deal with the obvious rewriting for the cases where the
|
-- condition of the IF is known at compile time to be True or False.
|
-- condition of the IF is known at compile time to be True or False.
|
|
|
-- Third, we remove elsif parts which have non-empty Condition_Actions and
|
-- Third, we remove elsif parts which have non-empty Condition_Actions and
|
-- rewrite as independent if statements. For example:
|
-- rewrite as independent if statements. For example:
|
|
|
-- if x then xs
|
-- if x then xs
|
-- elsif y then ys
|
-- elsif y then ys
|
-- ...
|
-- ...
|
-- end if;
|
-- end if;
|
|
|
-- becomes
|
-- becomes
|
--
|
--
|
-- if x then xs
|
-- if x then xs
|
-- else
|
-- else
|
-- <<condition actions of y>>
|
-- <<condition actions of y>>
|
-- if y then ys
|
-- if y then ys
|
-- ...
|
-- ...
|
-- end if;
|
-- end if;
|
-- end if;
|
-- end if;
|
|
|
-- This rewriting is needed if at least one elsif part has a non-empty
|
-- This rewriting is needed if at least one elsif part has a non-empty
|
-- Condition_Actions list. We also do the same processing if there is a
|
-- Condition_Actions list. We also do the same processing if there is a
|
-- constant condition in an elsif part (in conjunction with the first
|
-- constant condition in an elsif part (in conjunction with the first
|
-- processing step mentioned above, for the recursive call made to deal
|
-- processing step mentioned above, for the recursive call made to deal
|
-- with the created inner if, this deals with properly optimizing the
|
-- with the created inner if, this deals with properly optimizing the
|
-- cases of constant elsif conditions).
|
-- cases of constant elsif conditions).
|
|
|
procedure Expand_N_If_Statement (N : Node_Id) is
|
procedure Expand_N_If_Statement (N : Node_Id) is
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Hed : Node_Id;
|
Hed : Node_Id;
|
E : Node_Id;
|
E : Node_Id;
|
New_If : Node_Id;
|
New_If : Node_Id;
|
|
|
Warn_If_Deleted : constant Boolean :=
|
Warn_If_Deleted : constant Boolean :=
|
Warn_On_Deleted_Code and then Comes_From_Source (N);
|
Warn_On_Deleted_Code and then Comes_From_Source (N);
|
-- Indicates whether we want warnings when we delete branches of the
|
-- Indicates whether we want warnings when we delete branches of the
|
-- if statement based on constant condition analysis. We never want
|
-- if statement based on constant condition analysis. We never want
|
-- these warnings for expander generated code.
|
-- these warnings for expander generated code.
|
|
|
begin
|
begin
|
Process_Statements_For_Controlled_Objects (N);
|
Process_Statements_For_Controlled_Objects (N);
|
|
|
Adjust_Condition (Condition (N));
|
Adjust_Condition (Condition (N));
|
|
|
-- The following loop deals with constant conditions for the IF. We
|
-- The following loop deals with constant conditions for the IF. We
|
-- need a loop because as we eliminate False conditions, we grab the
|
-- need a loop because as we eliminate False conditions, we grab the
|
-- first elsif condition and use it as the primary condition.
|
-- first elsif condition and use it as the primary condition.
|
|
|
while Compile_Time_Known_Value (Condition (N)) loop
|
while Compile_Time_Known_Value (Condition (N)) loop
|
|
|
-- If condition is True, we can simply rewrite the if statement now
|
-- If condition is True, we can simply rewrite the if statement now
|
-- by replacing it by the series of then statements.
|
-- by replacing it by the series of then statements.
|
|
|
if Is_True (Expr_Value (Condition (N))) then
|
if Is_True (Expr_Value (Condition (N))) then
|
|
|
-- All the else parts can be killed
|
-- All the else parts can be killed
|
|
|
Kill_Dead_Code (Elsif_Parts (N), Warn_If_Deleted);
|
Kill_Dead_Code (Elsif_Parts (N), Warn_If_Deleted);
|
Kill_Dead_Code (Else_Statements (N), Warn_If_Deleted);
|
Kill_Dead_Code (Else_Statements (N), Warn_If_Deleted);
|
|
|
Hed := Remove_Head (Then_Statements (N));
|
Hed := Remove_Head (Then_Statements (N));
|
Insert_List_After (N, Then_Statements (N));
|
Insert_List_After (N, Then_Statements (N));
|
Rewrite (N, Hed);
|
Rewrite (N, Hed);
|
return;
|
return;
|
|
|
-- If condition is False, then we can delete the condition and
|
-- If condition is False, then we can delete the condition and
|
-- the Then statements
|
-- the Then statements
|
|
|
else
|
else
|
-- We do not delete the condition if constant condition warnings
|
-- We do not delete the condition if constant condition warnings
|
-- are enabled, since otherwise we end up deleting the desired
|
-- are enabled, since otherwise we end up deleting the desired
|
-- warning. Of course the backend will get rid of this True/False
|
-- warning. Of course the backend will get rid of this True/False
|
-- test anyway, so nothing is lost here.
|
-- test anyway, so nothing is lost here.
|
|
|
if not Constant_Condition_Warnings then
|
if not Constant_Condition_Warnings then
|
Kill_Dead_Code (Condition (N));
|
Kill_Dead_Code (Condition (N));
|
end if;
|
end if;
|
|
|
Kill_Dead_Code (Then_Statements (N), Warn_If_Deleted);
|
Kill_Dead_Code (Then_Statements (N), Warn_If_Deleted);
|
|
|
-- If there are no elsif statements, then we simply replace the
|
-- If there are no elsif statements, then we simply replace the
|
-- entire if statement by the sequence of else statements.
|
-- entire if statement by the sequence of else statements.
|
|
|
if No (Elsif_Parts (N)) then
|
if No (Elsif_Parts (N)) then
|
if No (Else_Statements (N))
|
if No (Else_Statements (N))
|
or else Is_Empty_List (Else_Statements (N))
|
or else Is_Empty_List (Else_Statements (N))
|
then
|
then
|
Rewrite (N,
|
Rewrite (N,
|
Make_Null_Statement (Sloc (N)));
|
Make_Null_Statement (Sloc (N)));
|
else
|
else
|
Hed := Remove_Head (Else_Statements (N));
|
Hed := Remove_Head (Else_Statements (N));
|
Insert_List_After (N, Else_Statements (N));
|
Insert_List_After (N, Else_Statements (N));
|
Rewrite (N, Hed);
|
Rewrite (N, Hed);
|
end if;
|
end if;
|
|
|
return;
|
return;
|
|
|
-- If there are elsif statements, the first of them becomes the
|
-- If there are elsif statements, the first of them becomes the
|
-- if/then section of the rebuilt if statement This is the case
|
-- if/then section of the rebuilt if statement This is the case
|
-- where we loop to reprocess this copied condition.
|
-- where we loop to reprocess this copied condition.
|
|
|
else
|
else
|
Hed := Remove_Head (Elsif_Parts (N));
|
Hed := Remove_Head (Elsif_Parts (N));
|
Insert_Actions (N, Condition_Actions (Hed));
|
Insert_Actions (N, Condition_Actions (Hed));
|
Set_Condition (N, Condition (Hed));
|
Set_Condition (N, Condition (Hed));
|
Set_Then_Statements (N, Then_Statements (Hed));
|
Set_Then_Statements (N, Then_Statements (Hed));
|
|
|
-- Hed might have been captured as the condition determining
|
-- Hed might have been captured as the condition determining
|
-- the current value for an entity. Now it is detached from
|
-- the current value for an entity. Now it is detached from
|
-- the tree, so a Current_Value pointer in the condition might
|
-- the tree, so a Current_Value pointer in the condition might
|
-- need to be updated.
|
-- need to be updated.
|
|
|
Set_Current_Value_Condition (N);
|
Set_Current_Value_Condition (N);
|
|
|
if Is_Empty_List (Elsif_Parts (N)) then
|
if Is_Empty_List (Elsif_Parts (N)) then
|
Set_Elsif_Parts (N, No_List);
|
Set_Elsif_Parts (N, No_List);
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end if;
|
end loop;
|
end loop;
|
|
|
-- Loop through elsif parts, dealing with constant conditions and
|
-- Loop through elsif parts, dealing with constant conditions and
|
-- possible expression actions that are present.
|
-- possible expression actions that are present.
|
|
|
if Present (Elsif_Parts (N)) then
|
if Present (Elsif_Parts (N)) then
|
E := First (Elsif_Parts (N));
|
E := First (Elsif_Parts (N));
|
while Present (E) loop
|
while Present (E) loop
|
Process_Statements_For_Controlled_Objects (E);
|
Process_Statements_For_Controlled_Objects (E);
|
|
|
Adjust_Condition (Condition (E));
|
Adjust_Condition (Condition (E));
|
|
|
-- If there are condition actions, then rewrite the if statement
|
-- If there are condition actions, then rewrite the if statement
|
-- as indicated above. We also do the same rewrite for a True or
|
-- as indicated above. We also do the same rewrite for a True or
|
-- False condition. The further processing of this constant
|
-- False condition. The further processing of this constant
|
-- condition is then done by the recursive call to expand the
|
-- condition is then done by the recursive call to expand the
|
-- newly created if statement
|
-- newly created if statement
|
|
|
if Present (Condition_Actions (E))
|
if Present (Condition_Actions (E))
|
or else Compile_Time_Known_Value (Condition (E))
|
or else Compile_Time_Known_Value (Condition (E))
|
then
|
then
|
-- Note this is not an implicit if statement, since it is part
|
-- Note this is not an implicit if statement, since it is part
|
-- of an explicit if statement in the source (or of an implicit
|
-- of an explicit if statement in the source (or of an implicit
|
-- if statement that has already been tested).
|
-- if statement that has already been tested).
|
|
|
New_If :=
|
New_If :=
|
Make_If_Statement (Sloc (E),
|
Make_If_Statement (Sloc (E),
|
Condition => Condition (E),
|
Condition => Condition (E),
|
Then_Statements => Then_Statements (E),
|
Then_Statements => Then_Statements (E),
|
Elsif_Parts => No_List,
|
Elsif_Parts => No_List,
|
Else_Statements => Else_Statements (N));
|
Else_Statements => Else_Statements (N));
|
|
|
-- Elsif parts for new if come from remaining elsif's of parent
|
-- Elsif parts for new if come from remaining elsif's of parent
|
|
|
while Present (Next (E)) loop
|
while Present (Next (E)) loop
|
if No (Elsif_Parts (New_If)) then
|
if No (Elsif_Parts (New_If)) then
|
Set_Elsif_Parts (New_If, New_List);
|
Set_Elsif_Parts (New_If, New_List);
|
end if;
|
end if;
|
|
|
Append (Remove_Next (E), Elsif_Parts (New_If));
|
Append (Remove_Next (E), Elsif_Parts (New_If));
|
end loop;
|
end loop;
|
|
|
Set_Else_Statements (N, New_List (New_If));
|
Set_Else_Statements (N, New_List (New_If));
|
|
|
if Present (Condition_Actions (E)) then
|
if Present (Condition_Actions (E)) then
|
Insert_List_Before (New_If, Condition_Actions (E));
|
Insert_List_Before (New_If, Condition_Actions (E));
|
end if;
|
end if;
|
|
|
Remove (E);
|
Remove (E);
|
|
|
if Is_Empty_List (Elsif_Parts (N)) then
|
if Is_Empty_List (Elsif_Parts (N)) then
|
Set_Elsif_Parts (N, No_List);
|
Set_Elsif_Parts (N, No_List);
|
end if;
|
end if;
|
|
|
Analyze (New_If);
|
Analyze (New_If);
|
return;
|
return;
|
|
|
-- No special processing for that elsif part, move to next
|
-- No special processing for that elsif part, move to next
|
|
|
else
|
else
|
Next (E);
|
Next (E);
|
end if;
|
end if;
|
end loop;
|
end loop;
|
end if;
|
end if;
|
|
|
-- Some more optimizations applicable if we still have an IF statement
|
-- Some more optimizations applicable if we still have an IF statement
|
|
|
if Nkind (N) /= N_If_Statement then
|
if Nkind (N) /= N_If_Statement then
|
return;
|
return;
|
end if;
|
end if;
|
|
|
-- Another optimization, special cases that can be simplified
|
-- Another optimization, special cases that can be simplified
|
|
|
-- if expression then
|
-- if expression then
|
-- return true;
|
-- return true;
|
-- else
|
-- else
|
-- return false;
|
-- return false;
|
-- end if;
|
-- end if;
|
|
|
-- can be changed to:
|
-- can be changed to:
|
|
|
-- return expression;
|
-- return expression;
|
|
|
-- and
|
-- and
|
|
|
-- if expression then
|
-- if expression then
|
-- return false;
|
-- return false;
|
-- else
|
-- else
|
-- return true;
|
-- return true;
|
-- end if;
|
-- end if;
|
|
|
-- can be changed to:
|
-- can be changed to:
|
|
|
-- return not (expression);
|
-- return not (expression);
|
|
|
-- Only do these optimizations if we are at least at -O1 level and
|
-- Only do these optimizations if we are at least at -O1 level and
|
-- do not do them if control flow optimizations are suppressed.
|
-- do not do them if control flow optimizations are suppressed.
|
|
|
if Optimization_Level > 0
|
if Optimization_Level > 0
|
and then not Opt.Suppress_Control_Flow_Optimizations
|
and then not Opt.Suppress_Control_Flow_Optimizations
|
then
|
then
|
if Nkind (N) = N_If_Statement
|
if Nkind (N) = N_If_Statement
|
and then No (Elsif_Parts (N))
|
and then No (Elsif_Parts (N))
|
and then Present (Else_Statements (N))
|
and then Present (Else_Statements (N))
|
and then List_Length (Then_Statements (N)) = 1
|
and then List_Length (Then_Statements (N)) = 1
|
and then List_Length (Else_Statements (N)) = 1
|
and then List_Length (Else_Statements (N)) = 1
|
then
|
then
|
declare
|
declare
|
Then_Stm : constant Node_Id := First (Then_Statements (N));
|
Then_Stm : constant Node_Id := First (Then_Statements (N));
|
Else_Stm : constant Node_Id := First (Else_Statements (N));
|
Else_Stm : constant Node_Id := First (Else_Statements (N));
|
|
|
begin
|
begin
|
if Nkind (Then_Stm) = N_Simple_Return_Statement
|
if Nkind (Then_Stm) = N_Simple_Return_Statement
|
and then
|
and then
|
Nkind (Else_Stm) = N_Simple_Return_Statement
|
Nkind (Else_Stm) = N_Simple_Return_Statement
|
then
|
then
|
declare
|
declare
|
Then_Expr : constant Node_Id := Expression (Then_Stm);
|
Then_Expr : constant Node_Id := Expression (Then_Stm);
|
Else_Expr : constant Node_Id := Expression (Else_Stm);
|
Else_Expr : constant Node_Id := Expression (Else_Stm);
|
|
|
begin
|
begin
|
if Nkind (Then_Expr) = N_Identifier
|
if Nkind (Then_Expr) = N_Identifier
|
and then
|
and then
|
Nkind (Else_Expr) = N_Identifier
|
Nkind (Else_Expr) = N_Identifier
|
then
|
then
|
if Entity (Then_Expr) = Standard_True
|
if Entity (Then_Expr) = Standard_True
|
and then Entity (Else_Expr) = Standard_False
|
and then Entity (Else_Expr) = Standard_False
|
then
|
then
|
Rewrite (N,
|
Rewrite (N,
|
Make_Simple_Return_Statement (Loc,
|
Make_Simple_Return_Statement (Loc,
|
Expression => Relocate_Node (Condition (N))));
|
Expression => Relocate_Node (Condition (N))));
|
Analyze (N);
|
Analyze (N);
|
return;
|
return;
|
|
|
elsif Entity (Then_Expr) = Standard_False
|
elsif Entity (Then_Expr) = Standard_False
|
and then Entity (Else_Expr) = Standard_True
|
and then Entity (Else_Expr) = Standard_True
|
then
|
then
|
Rewrite (N,
|
Rewrite (N,
|
Make_Simple_Return_Statement (Loc,
|
Make_Simple_Return_Statement (Loc,
|
Expression =>
|
Expression =>
|
Make_Op_Not (Loc,
|
Make_Op_Not (Loc,
|
Right_Opnd =>
|
Right_Opnd =>
|
Relocate_Node (Condition (N)))));
|
Relocate_Node (Condition (N)))));
|
Analyze (N);
|
Analyze (N);
|
return;
|
return;
|
end if;
|
end if;
|
end if;
|
end if;
|
end;
|
end;
|
end if;
|
end if;
|
end;
|
end;
|
end if;
|
end if;
|
end if;
|
end if;
|
end Expand_N_If_Statement;
|
end Expand_N_If_Statement;
|
|
|
--------------------------
|
--------------------------
|
-- Expand_Iterator_Loop --
|
-- Expand_Iterator_Loop --
|
--------------------------
|
--------------------------
|
|
|
procedure Expand_Iterator_Loop (N : Node_Id) is
|
procedure Expand_Iterator_Loop (N : Node_Id) is
|
Isc : constant Node_Id := Iteration_Scheme (N);
|
Isc : constant Node_Id := Iteration_Scheme (N);
|
I_Spec : constant Node_Id := Iterator_Specification (Isc);
|
I_Spec : constant Node_Id := Iterator_Specification (Isc);
|
Id : constant Entity_Id := Defining_Identifier (I_Spec);
|
Id : constant Entity_Id := Defining_Identifier (I_Spec);
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
|
|
Container : constant Node_Id := Name (I_Spec);
|
Container : constant Node_Id := Name (I_Spec);
|
Container_Typ : constant Entity_Id := Base_Type (Etype (Container));
|
Container_Typ : constant Entity_Id := Base_Type (Etype (Container));
|
Cursor : Entity_Id;
|
Cursor : Entity_Id;
|
Iterator : Entity_Id;
|
Iterator : Entity_Id;
|
New_Loop : Node_Id;
|
New_Loop : Node_Id;
|
Stats : List_Id := Statements (N);
|
Stats : List_Id := Statements (N);
|
|
|
begin
|
begin
|
-- Processing for arrays
|
-- Processing for arrays
|
|
|
if Is_Array_Type (Container_Typ) then
|
if Is_Array_Type (Container_Typ) then
|
|
|
-- for Element of Array loop
|
-- for Element of Array loop
|
--
|
--
|
-- This case requires an internally generated cursor to iterate over
|
-- This case requires an internally generated cursor to iterate over
|
-- the array.
|
-- the array.
|
|
|
if Of_Present (I_Spec) then
|
if Of_Present (I_Spec) then
|
Iterator := Make_Temporary (Loc, 'C');
|
Iterator := Make_Temporary (Loc, 'C');
|
|
|
-- Generate:
|
-- Generate:
|
-- Element : Component_Type renames Container (Iterator);
|
-- Element : Component_Type renames Container (Iterator);
|
|
|
Prepend_To (Stats,
|
Prepend_To (Stats,
|
Make_Object_Renaming_Declaration (Loc,
|
Make_Object_Renaming_Declaration (Loc,
|
Defining_Identifier => Id,
|
Defining_Identifier => Id,
|
Subtype_Mark =>
|
Subtype_Mark =>
|
New_Reference_To (Component_Type (Container_Typ), Loc),
|
New_Reference_To (Component_Type (Container_Typ), Loc),
|
Name =>
|
Name =>
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix => Relocate_Node (Container),
|
Prefix => Relocate_Node (Container),
|
Expressions => New_List (
|
Expressions => New_List (
|
New_Reference_To (Iterator, Loc)))));
|
New_Reference_To (Iterator, Loc)))));
|
|
|
-- for Index in Array loop
|
-- for Index in Array loop
|
|
|
-- This case utilizes the already given iterator name
|
-- This case utilizes the already given iterator name
|
|
|
else
|
else
|
Iterator := Id;
|
Iterator := Id;
|
end if;
|
end if;
|
|
|
-- Generate:
|
-- Generate:
|
-- for Iterator in [reverse] Container'Range loop
|
-- for Iterator in [reverse] Container'Range loop
|
-- Element : Component_Type renames Container (Iterator);
|
-- Element : Component_Type renames Container (Iterator);
|
-- -- for the "of" form
|
-- -- for the "of" form
|
|
|
-- <original loop statements>
|
-- <original loop statements>
|
-- end loop;
|
-- end loop;
|
|
|
New_Loop :=
|
New_Loop :=
|
Make_Loop_Statement (Loc,
|
Make_Loop_Statement (Loc,
|
Iteration_Scheme =>
|
Iteration_Scheme =>
|
Make_Iteration_Scheme (Loc,
|
Make_Iteration_Scheme (Loc,
|
Loop_Parameter_Specification =>
|
Loop_Parameter_Specification =>
|
Make_Loop_Parameter_Specification (Loc,
|
Make_Loop_Parameter_Specification (Loc,
|
Defining_Identifier => Iterator,
|
Defining_Identifier => Iterator,
|
Discrete_Subtype_Definition =>
|
Discrete_Subtype_Definition =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix => Relocate_Node (Container),
|
Prefix => Relocate_Node (Container),
|
Attribute_Name => Name_Range),
|
Attribute_Name => Name_Range),
|
Reverse_Present => Reverse_Present (I_Spec))),
|
Reverse_Present => Reverse_Present (I_Spec))),
|
Statements => Stats,
|
Statements => Stats,
|
End_Label => Empty);
|
End_Label => Empty);
|
|
|
-- Processing for containers
|
-- Processing for containers
|
|
|
else
|
else
|
-- For an "of" iterator the name is a container expression, which
|
-- For an "of" iterator the name is a container expression, which
|
-- is transformed into a call to the default iterator.
|
-- is transformed into a call to the default iterator.
|
|
|
-- For an iterator of the form "in" the name is a function call
|
-- For an iterator of the form "in" the name is a function call
|
-- that delivers an iterator type.
|
-- that delivers an iterator type.
|
|
|
-- In both cases, analysis of the iterator has introduced an object
|
-- In both cases, analysis of the iterator has introduced an object
|
-- declaration to capture the domain, so that Container is an entity.
|
-- declaration to capture the domain, so that Container is an entity.
|
|
|
-- The for loop is expanded into a while loop which uses a container
|
-- The for loop is expanded into a while loop which uses a container
|
-- specific cursor to desgnate each element.
|
-- specific cursor to desgnate each element.
|
|
|
-- Iter : Iterator_Type := Container.Iterate;
|
-- Iter : Iterator_Type := Container.Iterate;
|
-- Cursor : Cursor_type := First (Iter);
|
-- Cursor : Cursor_type := First (Iter);
|
-- while Has_Element (Iter) loop
|
-- while Has_Element (Iter) loop
|
-- declare
|
-- declare
|
-- -- The block is added when Element_Type is controlled
|
-- -- The block is added when Element_Type is controlled
|
|
|
-- Obj : Pack.Element_Type := Element (Cursor);
|
-- Obj : Pack.Element_Type := Element (Cursor);
|
-- -- for the "of" loop form
|
-- -- for the "of" loop form
|
-- begin
|
-- begin
|
-- <original loop statements>
|
-- <original loop statements>
|
-- end;
|
-- end;
|
|
|
-- Cursor := Iter.Next (Cursor);
|
-- Cursor := Iter.Next (Cursor);
|
-- end loop;
|
-- end loop;
|
|
|
-- If "reverse" is present, then the initialization of the cursor
|
-- If "reverse" is present, then the initialization of the cursor
|
-- uses Last and the step becomes Prev. Pack is the name of the
|
-- uses Last and the step becomes Prev. Pack is the name of the
|
-- scope where the container package is instantiated.
|
-- scope where the container package is instantiated.
|
|
|
declare
|
declare
|
Element_Type : constant Entity_Id := Etype (Id);
|
Element_Type : constant Entity_Id := Etype (Id);
|
Iter_Type : Entity_Id;
|
Iter_Type : Entity_Id;
|
Pack : Entity_Id;
|
Pack : Entity_Id;
|
Decl : Node_Id;
|
Decl : Node_Id;
|
Name_Init : Name_Id;
|
Name_Init : Name_Id;
|
Name_Step : Name_Id;
|
Name_Step : Name_Id;
|
|
|
begin
|
begin
|
-- The type of the iterator is the return type of the Iterate
|
-- The type of the iterator is the return type of the Iterate
|
-- function used. For the "of" form this is the default iterator
|
-- function used. For the "of" form this is the default iterator
|
-- for the type, otherwise it is the type of the explicit
|
-- for the type, otherwise it is the type of the explicit
|
-- function used in the iterator specification. The most common
|
-- function used in the iterator specification. The most common
|
-- case will be an Iterate function in the container package.
|
-- case will be an Iterate function in the container package.
|
|
|
-- The primitive operations of the container type may not be
|
-- The primitive operations of the container type may not be
|
-- use-visible, so we introduce the name of the enclosing package
|
-- use-visible, so we introduce the name of the enclosing package
|
-- in the declarations below. The Iterator type is declared in a
|
-- in the declarations below. The Iterator type is declared in a
|
-- an instance within the container package itself.
|
-- an instance within the container package itself.
|
|
|
-- If the container type is a derived type, the cursor type is
|
-- If the container type is a derived type, the cursor type is
|
-- found in the package of the parent type.
|
-- found in the package of the parent type.
|
|
|
if Is_Derived_Type (Container_Typ) then
|
if Is_Derived_Type (Container_Typ) then
|
Pack := Scope (Root_Type (Container_Typ));
|
Pack := Scope (Root_Type (Container_Typ));
|
else
|
else
|
Pack := Scope (Container_Typ);
|
Pack := Scope (Container_Typ);
|
end if;
|
end if;
|
|
|
Iter_Type := Etype (Name (I_Spec));
|
Iter_Type := Etype (Name (I_Spec));
|
|
|
-- The "of" case uses an internally generated cursor whose type
|
-- The "of" case uses an internally generated cursor whose type
|
-- is found in the container package. The domain of iteration
|
-- is found in the container package. The domain of iteration
|
-- is expanded into a call to the default Iterator function, but
|
-- is expanded into a call to the default Iterator function, but
|
-- this expansion does not take place in quantified expressions
|
-- this expansion does not take place in quantified expressions
|
-- that are analyzed with expansion disabled, and in that case the
|
-- that are analyzed with expansion disabled, and in that case the
|
-- type of the iterator must be obtained from the aspect.
|
-- type of the iterator must be obtained from the aspect.
|
|
|
if Of_Present (I_Spec) then
|
if Of_Present (I_Spec) then
|
declare
|
declare
|
Default_Iter : constant Entity_Id :=
|
Default_Iter : constant Entity_Id :=
|
Entity
|
Entity
|
(Find_Aspect
|
(Find_Aspect
|
(Etype (Container),
|
(Etype (Container),
|
Aspect_Default_Iterator));
|
Aspect_Default_Iterator));
|
|
|
Container_Arg : Node_Id;
|
Container_Arg : Node_Id;
|
Ent : Entity_Id;
|
Ent : Entity_Id;
|
|
|
begin
|
begin
|
Cursor := Make_Temporary (Loc, 'I');
|
Cursor := Make_Temporary (Loc, 'I');
|
|
|
-- For an container element iterator, the iterator type
|
-- For an container element iterator, the iterator type
|
-- is obtained from the corresponding aspect.
|
-- is obtained from the corresponding aspect.
|
|
|
Iter_Type := Etype (Default_Iter);
|
Iter_Type := Etype (Default_Iter);
|
Pack := Scope (Iter_Type);
|
Pack := Scope (Iter_Type);
|
|
|
-- Rewrite domain of iteration as a call to the default
|
-- Rewrite domain of iteration as a call to the default
|
-- iterator for the container type. If the container is
|
-- iterator for the container type. If the container is
|
-- a derived type and the aspect is inherited, convert
|
-- a derived type and the aspect is inherited, convert
|
-- container to parent type. The Cursor type is also
|
-- container to parent type. The Cursor type is also
|
-- inherited from the scope of the parent.
|
-- inherited from the scope of the parent.
|
|
|
if Base_Type (Etype (Container)) =
|
if Base_Type (Etype (Container)) =
|
Base_Type (Etype (First_Formal (Default_Iter)))
|
Base_Type (Etype (First_Formal (Default_Iter)))
|
then
|
then
|
Container_Arg := New_Copy_Tree (Container);
|
Container_Arg := New_Copy_Tree (Container);
|
|
|
else
|
else
|
Container_Arg :=
|
Container_Arg :=
|
Make_Type_Conversion (Loc,
|
Make_Type_Conversion (Loc,
|
Subtype_Mark =>
|
Subtype_Mark =>
|
New_Occurrence_Of
|
New_Occurrence_Of
|
(Etype (First_Formal (Default_Iter)), Loc),
|
(Etype (First_Formal (Default_Iter)), Loc),
|
Expression => New_Copy_Tree (Container));
|
Expression => New_Copy_Tree (Container));
|
end if;
|
end if;
|
|
|
Rewrite (Name (I_Spec),
|
Rewrite (Name (I_Spec),
|
Make_Function_Call (Loc,
|
Make_Function_Call (Loc,
|
Name => New_Occurrence_Of (Default_Iter, Loc),
|
Name => New_Occurrence_Of (Default_Iter, Loc),
|
Parameter_Associations =>
|
Parameter_Associations =>
|
New_List (Container_Arg)));
|
New_List (Container_Arg)));
|
Analyze_And_Resolve (Name (I_Spec));
|
Analyze_And_Resolve (Name (I_Spec));
|
|
|
-- Find cursor type in proper iterator package, which is an
|
-- Find cursor type in proper iterator package, which is an
|
-- instantiation of Iterator_Interfaces.
|
-- instantiation of Iterator_Interfaces.
|
|
|
Ent := First_Entity (Pack);
|
Ent := First_Entity (Pack);
|
while Present (Ent) loop
|
while Present (Ent) loop
|
if Chars (Ent) = Name_Cursor then
|
if Chars (Ent) = Name_Cursor then
|
Set_Etype (Cursor, Etype (Ent));
|
Set_Etype (Cursor, Etype (Ent));
|
exit;
|
exit;
|
end if;
|
end if;
|
Next_Entity (Ent);
|
Next_Entity (Ent);
|
end loop;
|
end loop;
|
|
|
-- Generate:
|
-- Generate:
|
-- Id : Element_Type renames Container (Cursor);
|
-- Id : Element_Type renames Container (Cursor);
|
-- This assumes that the container type has an indexing
|
-- This assumes that the container type has an indexing
|
-- operation with Cursor. The check that this operation
|
-- operation with Cursor. The check that this operation
|
-- exists is performed in Check_Container_Indexing.
|
-- exists is performed in Check_Container_Indexing.
|
|
|
Decl :=
|
Decl :=
|
Make_Object_Renaming_Declaration (Loc,
|
Make_Object_Renaming_Declaration (Loc,
|
Defining_Identifier => Id,
|
Defining_Identifier => Id,
|
Subtype_Mark =>
|
Subtype_Mark =>
|
New_Reference_To (Element_Type, Loc),
|
New_Reference_To (Element_Type, Loc),
|
Name =>
|
Name =>
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix => Relocate_Node (Container_Arg),
|
Prefix => Relocate_Node (Container_Arg),
|
Expressions =>
|
Expressions =>
|
New_List (New_Occurrence_Of (Cursor, Loc))));
|
New_List (New_Occurrence_Of (Cursor, Loc))));
|
|
|
-- If the container holds controlled objects, wrap the loop
|
-- If the container holds controlled objects, wrap the loop
|
-- statements and element renaming declaration with a block.
|
-- statements and element renaming declaration with a block.
|
-- This ensures that the result of Element (Cusor) is
|
-- This ensures that the result of Element (Cusor) is
|
-- cleaned up after each iteration of the loop.
|
-- cleaned up after each iteration of the loop.
|
|
|
if Needs_Finalization (Element_Type) then
|
if Needs_Finalization (Element_Type) then
|
|
|
-- Generate:
|
-- Generate:
|
-- declare
|
-- declare
|
-- Id : Element_Type := Element (curosr);
|
-- Id : Element_Type := Element (curosr);
|
-- begin
|
-- begin
|
-- <original loop statements>
|
-- <original loop statements>
|
-- end;
|
-- end;
|
|
|
Stats := New_List (
|
Stats := New_List (
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Declarations => New_List (Decl),
|
Declarations => New_List (Decl),
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Statements => Stats)));
|
Statements => Stats)));
|
|
|
-- Elements do not need finalization
|
-- Elements do not need finalization
|
|
|
else
|
else
|
Prepend_To (Stats, Decl);
|
Prepend_To (Stats, Decl);
|
end if;
|
end if;
|
end;
|
end;
|
|
|
-- X in Iterate (S) : type of iterator is type of explicitly
|
-- X in Iterate (S) : type of iterator is type of explicitly
|
-- given Iterate function, and the loop variable is the cursor.
|
-- given Iterate function, and the loop variable is the cursor.
|
-- It will be assigned in the loop and must be a variable.
|
-- It will be assigned in the loop and must be a variable.
|
|
|
else
|
else
|
Cursor := Id;
|
Cursor := Id;
|
Set_Ekind (Cursor, E_Variable);
|
Set_Ekind (Cursor, E_Variable);
|
end if;
|
end if;
|
|
|
Iterator := Make_Temporary (Loc, 'I');
|
Iterator := Make_Temporary (Loc, 'I');
|
|
|
-- Determine the advancement and initialization steps for the
|
-- Determine the advancement and initialization steps for the
|
-- cursor.
|
-- cursor.
|
|
|
-- Analysis of the expanded loop will verify that the container
|
-- Analysis of the expanded loop will verify that the container
|
-- has a reverse iterator.
|
-- has a reverse iterator.
|
|
|
if Reverse_Present (I_Spec) then
|
if Reverse_Present (I_Spec) then
|
Name_Init := Name_Last;
|
Name_Init := Name_Last;
|
Name_Step := Name_Previous;
|
Name_Step := Name_Previous;
|
|
|
else
|
else
|
Name_Init := Name_First;
|
Name_Init := Name_First;
|
Name_Step := Name_Next;
|
Name_Step := Name_Next;
|
end if;
|
end if;
|
|
|
-- For both iterator forms, add a call to the step operation to
|
-- For both iterator forms, add a call to the step operation to
|
-- advance the cursor. Generate:
|
-- advance the cursor. Generate:
|
|
|
-- Cursor := Iterator.Next (Cursor);
|
-- Cursor := Iterator.Next (Cursor);
|
|
|
-- or else
|
-- or else
|
|
|
-- Cursor := Next (Cursor);
|
-- Cursor := Next (Cursor);
|
|
|
declare
|
declare
|
Rhs : Node_Id;
|
Rhs : Node_Id;
|
|
|
begin
|
begin
|
Rhs :=
|
Rhs :=
|
Make_Function_Call (Loc,
|
Make_Function_Call (Loc,
|
Name =>
|
Name =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => New_Reference_To (Iterator, Loc),
|
Prefix => New_Reference_To (Iterator, Loc),
|
Selector_Name => Make_Identifier (Loc, Name_Step)),
|
Selector_Name => Make_Identifier (Loc, Name_Step)),
|
Parameter_Associations => New_List (
|
Parameter_Associations => New_List (
|
New_Reference_To (Cursor, Loc)));
|
New_Reference_To (Cursor, Loc)));
|
|
|
Append_To (Stats,
|
Append_To (Stats,
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => New_Occurrence_Of (Cursor, Loc),
|
Name => New_Occurrence_Of (Cursor, Loc),
|
Expression => Rhs));
|
Expression => Rhs));
|
end;
|
end;
|
|
|
-- Generate:
|
-- Generate:
|
-- while Iterator.Has_Element loop
|
-- while Iterator.Has_Element loop
|
-- <Stats>
|
-- <Stats>
|
-- end loop;
|
-- end loop;
|
|
|
-- Has_Element is the second actual in the iterator package
|
-- Has_Element is the second actual in the iterator package
|
|
|
New_Loop :=
|
New_Loop :=
|
Make_Loop_Statement (Loc,
|
Make_Loop_Statement (Loc,
|
Iteration_Scheme =>
|
Iteration_Scheme =>
|
Make_Iteration_Scheme (Loc,
|
Make_Iteration_Scheme (Loc,
|
Condition =>
|
Condition =>
|
Make_Function_Call (Loc,
|
Make_Function_Call (Loc,
|
Name =>
|
Name =>
|
New_Occurrence_Of (
|
New_Occurrence_Of (
|
Next_Entity (First_Entity (Pack)), Loc),
|
Next_Entity (First_Entity (Pack)), Loc),
|
Parameter_Associations =>
|
Parameter_Associations =>
|
New_List (
|
New_List (
|
New_Reference_To (Cursor, Loc)))),
|
New_Reference_To (Cursor, Loc)))),
|
|
|
Statements => Stats,
|
Statements => Stats,
|
End_Label => Empty);
|
End_Label => Empty);
|
|
|
-- Create the declarations for Iterator and cursor and insert them
|
-- Create the declarations for Iterator and cursor and insert them
|
-- before the source loop. Given that the domain of iteration is
|
-- before the source loop. Given that the domain of iteration is
|
-- already an entity, the iterator is just a renaming of that
|
-- already an entity, the iterator is just a renaming of that
|
-- entity. Possible optimization ???
|
-- entity. Possible optimization ???
|
-- Generate:
|
-- Generate:
|
|
|
-- I : Iterator_Type renames Container;
|
-- I : Iterator_Type renames Container;
|
-- C : Cursor_Type := Container.[First | Last];
|
-- C : Cursor_Type := Container.[First | Last];
|
|
|
Insert_Action (N,
|
Insert_Action (N,
|
Make_Object_Renaming_Declaration (Loc,
|
Make_Object_Renaming_Declaration (Loc,
|
Defining_Identifier => Iterator,
|
Defining_Identifier => Iterator,
|
Subtype_Mark => New_Occurrence_Of (Iter_Type, Loc),
|
Subtype_Mark => New_Occurrence_Of (Iter_Type, Loc),
|
Name => Relocate_Node (Name (I_Spec))));
|
Name => Relocate_Node (Name (I_Spec))));
|
|
|
-- Create declaration for cursor
|
-- Create declaration for cursor
|
|
|
declare
|
declare
|
Decl : Node_Id;
|
Decl : Node_Id;
|
|
|
begin
|
begin
|
Decl :=
|
Decl :=
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Cursor,
|
Defining_Identifier => Cursor,
|
Object_Definition =>
|
Object_Definition =>
|
New_Occurrence_Of (Etype (Cursor), Loc),
|
New_Occurrence_Of (Etype (Cursor), Loc),
|
Expression =>
|
Expression =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => New_Reference_To (Iterator, Loc),
|
Prefix => New_Reference_To (Iterator, Loc),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Name_Init)));
|
Make_Identifier (Loc, Name_Init)));
|
|
|
-- The cursor is only modified in expanded code, so it appears
|
-- The cursor is only modified in expanded code, so it appears
|
-- as unassigned to the warning machinery. We must suppress
|
-- as unassigned to the warning machinery. We must suppress
|
-- this spurious warning explicitly.
|
-- this spurious warning explicitly.
|
|
|
Set_Warnings_Off (Cursor);
|
Set_Warnings_Off (Cursor);
|
Set_Assignment_OK (Decl);
|
Set_Assignment_OK (Decl);
|
|
|
Insert_Action (N, Decl);
|
Insert_Action (N, Decl);
|
end;
|
end;
|
|
|
-- If the range of iteration is given by a function call that
|
-- If the range of iteration is given by a function call that
|
-- returns a container, the finalization actions have been saved
|
-- returns a container, the finalization actions have been saved
|
-- in the Condition_Actions of the iterator. Insert them now at
|
-- in the Condition_Actions of the iterator. Insert them now at
|
-- the head of the loop.
|
-- the head of the loop.
|
|
|
if Present (Condition_Actions (Isc)) then
|
if Present (Condition_Actions (Isc)) then
|
Insert_List_Before (N, Condition_Actions (Isc));
|
Insert_List_Before (N, Condition_Actions (Isc));
|
end if;
|
end if;
|
end;
|
end;
|
end if;
|
end if;
|
|
|
Rewrite (N, New_Loop);
|
Rewrite (N, New_Loop);
|
Analyze (N);
|
Analyze (N);
|
end Expand_Iterator_Loop;
|
end Expand_Iterator_Loop;
|
|
|
-----------------------------
|
-----------------------------
|
-- Expand_N_Loop_Statement --
|
-- Expand_N_Loop_Statement --
|
-----------------------------
|
-----------------------------
|
|
|
-- 1. Remove null loop entirely
|
-- 1. Remove null loop entirely
|
-- 2. Deal with while condition for C/Fortran boolean
|
-- 2. Deal with while condition for C/Fortran boolean
|
-- 3. Deal with loops with a non-standard enumeration type range
|
-- 3. Deal with loops with a non-standard enumeration type range
|
-- 4. Deal with while loops where Condition_Actions is set
|
-- 4. Deal with while loops where Condition_Actions is set
|
-- 5. Deal with loops over predicated subtypes
|
-- 5. Deal with loops over predicated subtypes
|
-- 6. Deal with loops with iterators over arrays and containers
|
-- 6. Deal with loops with iterators over arrays and containers
|
-- 7. Insert polling call if required
|
-- 7. Insert polling call if required
|
|
|
procedure Expand_N_Loop_Statement (N : Node_Id) is
|
procedure Expand_N_Loop_Statement (N : Node_Id) is
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Isc : constant Node_Id := Iteration_Scheme (N);
|
Isc : constant Node_Id := Iteration_Scheme (N);
|
|
|
begin
|
begin
|
-- Delete null loop
|
-- Delete null loop
|
|
|
if Is_Null_Loop (N) then
|
if Is_Null_Loop (N) then
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
return;
|
return;
|
end if;
|
end if;
|
|
|
Process_Statements_For_Controlled_Objects (N);
|
Process_Statements_For_Controlled_Objects (N);
|
|
|
-- Deal with condition for C/Fortran Boolean
|
-- Deal with condition for C/Fortran Boolean
|
|
|
if Present (Isc) then
|
if Present (Isc) then
|
Adjust_Condition (Condition (Isc));
|
Adjust_Condition (Condition (Isc));
|
end if;
|
end if;
|
|
|
-- Generate polling call
|
-- Generate polling call
|
|
|
if Is_Non_Empty_List (Statements (N)) then
|
if Is_Non_Empty_List (Statements (N)) then
|
Generate_Poll_Call (First (Statements (N)));
|
Generate_Poll_Call (First (Statements (N)));
|
end if;
|
end if;
|
|
|
-- Nothing more to do for plain loop with no iteration scheme
|
-- Nothing more to do for plain loop with no iteration scheme
|
|
|
if No (Isc) then
|
if No (Isc) then
|
null;
|
null;
|
|
|
-- Case of for loop (Loop_Parameter_Specification present)
|
-- Case of for loop (Loop_Parameter_Specification present)
|
|
|
-- Note: we do not have to worry about validity checking of the for loop
|
-- Note: we do not have to worry about validity checking of the for loop
|
-- range bounds here, since they were frozen with constant declarations
|
-- range bounds here, since they were frozen with constant declarations
|
-- and it is during that process that the validity checking is done.
|
-- and it is during that process that the validity checking is done.
|
|
|
elsif Present (Loop_Parameter_Specification (Isc)) then
|
elsif Present (Loop_Parameter_Specification (Isc)) then
|
declare
|
declare
|
LPS : constant Node_Id := Loop_Parameter_Specification (Isc);
|
LPS : constant Node_Id := Loop_Parameter_Specification (Isc);
|
Loop_Id : constant Entity_Id := Defining_Identifier (LPS);
|
Loop_Id : constant Entity_Id := Defining_Identifier (LPS);
|
Ltype : constant Entity_Id := Etype (Loop_Id);
|
Ltype : constant Entity_Id := Etype (Loop_Id);
|
Btype : constant Entity_Id := Base_Type (Ltype);
|
Btype : constant Entity_Id := Base_Type (Ltype);
|
Expr : Node_Id;
|
Expr : Node_Id;
|
New_Id : Entity_Id;
|
New_Id : Entity_Id;
|
|
|
begin
|
begin
|
-- Deal with loop over predicates
|
-- Deal with loop over predicates
|
|
|
if Is_Discrete_Type (Ltype)
|
if Is_Discrete_Type (Ltype)
|
and then Present (Predicate_Function (Ltype))
|
and then Present (Predicate_Function (Ltype))
|
then
|
then
|
Expand_Predicated_Loop (N);
|
Expand_Predicated_Loop (N);
|
|
|
-- Handle the case where we have a for loop with the range type
|
-- Handle the case where we have a for loop with the range type
|
-- being an enumeration type with non-standard representation.
|
-- being an enumeration type with non-standard representation.
|
-- In this case we expand:
|
-- In this case we expand:
|
|
|
-- for x in [reverse] a .. b loop
|
-- for x in [reverse] a .. b loop
|
-- ...
|
-- ...
|
-- end loop;
|
-- end loop;
|
|
|
-- to
|
-- to
|
|
|
-- for xP in [reverse] integer
|
-- for xP in [reverse] integer
|
-- range etype'Pos (a) .. etype'Pos (b)
|
-- range etype'Pos (a) .. etype'Pos (b)
|
-- loop
|
-- loop
|
-- declare
|
-- declare
|
-- x : constant etype := Pos_To_Rep (xP);
|
-- x : constant etype := Pos_To_Rep (xP);
|
-- begin
|
-- begin
|
-- ...
|
-- ...
|
-- end;
|
-- end;
|
-- end loop;
|
-- end loop;
|
|
|
elsif Is_Enumeration_Type (Btype)
|
elsif Is_Enumeration_Type (Btype)
|
and then Present (Enum_Pos_To_Rep (Btype))
|
and then Present (Enum_Pos_To_Rep (Btype))
|
then
|
then
|
New_Id :=
|
New_Id :=
|
Make_Defining_Identifier (Loc,
|
Make_Defining_Identifier (Loc,
|
Chars => New_External_Name (Chars (Loop_Id), 'P'));
|
Chars => New_External_Name (Chars (Loop_Id), 'P'));
|
|
|
-- If the type has a contiguous representation, successive
|
-- If the type has a contiguous representation, successive
|
-- values can be generated as offsets from the first literal.
|
-- values can be generated as offsets from the first literal.
|
|
|
if Has_Contiguous_Rep (Btype) then
|
if Has_Contiguous_Rep (Btype) then
|
Expr :=
|
Expr :=
|
Unchecked_Convert_To (Btype,
|
Unchecked_Convert_To (Btype,
|
Make_Op_Add (Loc,
|
Make_Op_Add (Loc,
|
Left_Opnd =>
|
Left_Opnd =>
|
Make_Integer_Literal (Loc,
|
Make_Integer_Literal (Loc,
|
Enumeration_Rep (First_Literal (Btype))),
|
Enumeration_Rep (First_Literal (Btype))),
|
Right_Opnd => New_Reference_To (New_Id, Loc)));
|
Right_Opnd => New_Reference_To (New_Id, Loc)));
|
else
|
else
|
-- Use the constructed array Enum_Pos_To_Rep
|
-- Use the constructed array Enum_Pos_To_Rep
|
|
|
Expr :=
|
Expr :=
|
Make_Indexed_Component (Loc,
|
Make_Indexed_Component (Loc,
|
Prefix =>
|
Prefix =>
|
New_Reference_To (Enum_Pos_To_Rep (Btype), Loc),
|
New_Reference_To (Enum_Pos_To_Rep (Btype), Loc),
|
Expressions =>
|
Expressions =>
|
New_List (New_Reference_To (New_Id, Loc)));
|
New_List (New_Reference_To (New_Id, Loc)));
|
end if;
|
end if;
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_Loop_Statement (Loc,
|
Make_Loop_Statement (Loc,
|
Identifier => Identifier (N),
|
Identifier => Identifier (N),
|
|
|
Iteration_Scheme =>
|
Iteration_Scheme =>
|
Make_Iteration_Scheme (Loc,
|
Make_Iteration_Scheme (Loc,
|
Loop_Parameter_Specification =>
|
Loop_Parameter_Specification =>
|
Make_Loop_Parameter_Specification (Loc,
|
Make_Loop_Parameter_Specification (Loc,
|
Defining_Identifier => New_Id,
|
Defining_Identifier => New_Id,
|
Reverse_Present => Reverse_Present (LPS),
|
Reverse_Present => Reverse_Present (LPS),
|
|
|
Discrete_Subtype_Definition =>
|
Discrete_Subtype_Definition =>
|
Make_Subtype_Indication (Loc,
|
Make_Subtype_Indication (Loc,
|
|
|
Subtype_Mark =>
|
Subtype_Mark =>
|
New_Reference_To (Standard_Natural, Loc),
|
New_Reference_To (Standard_Natural, Loc),
|
|
|
Constraint =>
|
Constraint =>
|
Make_Range_Constraint (Loc,
|
Make_Range_Constraint (Loc,
|
Range_Expression =>
|
Range_Expression =>
|
Make_Range (Loc,
|
Make_Range (Loc,
|
|
|
Low_Bound =>
|
Low_Bound =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
New_Reference_To (Btype, Loc),
|
New_Reference_To (Btype, Loc),
|
|
|
Attribute_Name => Name_Pos,
|
Attribute_Name => Name_Pos,
|
|
|
Expressions => New_List (
|
Expressions => New_List (
|
Relocate_Node
|
Relocate_Node
|
(Type_Low_Bound (Ltype)))),
|
(Type_Low_Bound (Ltype)))),
|
|
|
High_Bound =>
|
High_Bound =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix =>
|
Prefix =>
|
New_Reference_To (Btype, Loc),
|
New_Reference_To (Btype, Loc),
|
|
|
Attribute_Name => Name_Pos,
|
Attribute_Name => Name_Pos,
|
|
|
Expressions => New_List (
|
Expressions => New_List (
|
Relocate_Node
|
Relocate_Node
|
(Type_High_Bound
|
(Type_High_Bound
|
(Ltype))))))))),
|
(Ltype))))))))),
|
|
|
Statements => New_List (
|
Statements => New_List (
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Declarations => New_List (
|
Declarations => New_List (
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Loop_Id,
|
Defining_Identifier => Loop_Id,
|
Constant_Present => True,
|
Constant_Present => True,
|
Object_Definition =>
|
Object_Definition =>
|
New_Reference_To (Ltype, Loc),
|
New_Reference_To (Ltype, Loc),
|
Expression => Expr)),
|
Expression => Expr)),
|
|
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Statements => Statements (N)))),
|
Statements => Statements (N)))),
|
|
|
End_Label => End_Label (N)));
|
End_Label => End_Label (N)));
|
|
|
-- The loop parameter's entity must be removed from the loop
|
-- The loop parameter's entity must be removed from the loop
|
-- scope's entity list, since it will now be located in the
|
-- scope's entity list, since it will now be located in the
|
-- new block scope. Any other entities already associated with
|
-- new block scope. Any other entities already associated with
|
-- the loop scope, such as the loop parameter's subtype, will
|
-- the loop scope, such as the loop parameter's subtype, will
|
-- remain there.
|
-- remain there.
|
|
|
pragma Assert (First_Entity (Scope (Loop_Id)) = Loop_Id);
|
pragma Assert (First_Entity (Scope (Loop_Id)) = Loop_Id);
|
Set_First_Entity (Scope (Loop_Id), Next_Entity (Loop_Id));
|
Set_First_Entity (Scope (Loop_Id), Next_Entity (Loop_Id));
|
|
|
if Last_Entity (Scope (Loop_Id)) = Loop_Id then
|
if Last_Entity (Scope (Loop_Id)) = Loop_Id then
|
Set_Last_Entity (Scope (Loop_Id), Empty);
|
Set_Last_Entity (Scope (Loop_Id), Empty);
|
end if;
|
end if;
|
|
|
Analyze (N);
|
Analyze (N);
|
|
|
-- Nothing to do with other cases of for loops
|
-- Nothing to do with other cases of for loops
|
|
|
else
|
else
|
null;
|
null;
|
end if;
|
end if;
|
end;
|
end;
|
|
|
-- Second case, if we have a while loop with Condition_Actions set, then
|
-- Second case, if we have a while loop with Condition_Actions set, then
|
-- we change it into a plain loop:
|
-- we change it into a plain loop:
|
|
|
-- while C loop
|
-- while C loop
|
-- ...
|
-- ...
|
-- end loop;
|
-- end loop;
|
|
|
-- changed to:
|
-- changed to:
|
|
|
-- loop
|
-- loop
|
-- <<condition actions>>
|
-- <<condition actions>>
|
-- exit when not C;
|
-- exit when not C;
|
-- ...
|
-- ...
|
-- end loop
|
-- end loop
|
|
|
elsif Present (Isc)
|
elsif Present (Isc)
|
and then Present (Condition_Actions (Isc))
|
and then Present (Condition_Actions (Isc))
|
and then Present (Condition (Isc))
|
and then Present (Condition (Isc))
|
then
|
then
|
declare
|
declare
|
ES : Node_Id;
|
ES : Node_Id;
|
|
|
begin
|
begin
|
ES :=
|
ES :=
|
Make_Exit_Statement (Sloc (Condition (Isc)),
|
Make_Exit_Statement (Sloc (Condition (Isc)),
|
Condition =>
|
Condition =>
|
Make_Op_Not (Sloc (Condition (Isc)),
|
Make_Op_Not (Sloc (Condition (Isc)),
|
Right_Opnd => Condition (Isc)));
|
Right_Opnd => Condition (Isc)));
|
|
|
Prepend (ES, Statements (N));
|
Prepend (ES, Statements (N));
|
Insert_List_Before (ES, Condition_Actions (Isc));
|
Insert_List_Before (ES, Condition_Actions (Isc));
|
|
|
-- This is not an implicit loop, since it is generated in response
|
-- This is not an implicit loop, since it is generated in response
|
-- to the loop statement being processed. If this is itself
|
-- to the loop statement being processed. If this is itself
|
-- implicit, the restriction has already been checked. If not,
|
-- implicit, the restriction has already been checked. If not,
|
-- it is an explicit loop.
|
-- it is an explicit loop.
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_Loop_Statement (Sloc (N),
|
Make_Loop_Statement (Sloc (N),
|
Identifier => Identifier (N),
|
Identifier => Identifier (N),
|
Statements => Statements (N),
|
Statements => Statements (N),
|
End_Label => End_Label (N)));
|
End_Label => End_Label (N)));
|
|
|
Analyze (N);
|
Analyze (N);
|
end;
|
end;
|
|
|
-- Here to deal with iterator case
|
-- Here to deal with iterator case
|
|
|
elsif Present (Isc)
|
elsif Present (Isc)
|
and then Present (Iterator_Specification (Isc))
|
and then Present (Iterator_Specification (Isc))
|
then
|
then
|
Expand_Iterator_Loop (N);
|
Expand_Iterator_Loop (N);
|
end if;
|
end if;
|
end Expand_N_Loop_Statement;
|
end Expand_N_Loop_Statement;
|
|
|
----------------------------
|
----------------------------
|
-- Expand_Predicated_Loop --
|
-- Expand_Predicated_Loop --
|
----------------------------
|
----------------------------
|
|
|
-- Note: the expander can handle generation of loops over predicated
|
-- Note: the expander can handle generation of loops over predicated
|
-- subtypes for both the dynamic and static cases. Depending on what
|
-- subtypes for both the dynamic and static cases. Depending on what
|
-- we decide is allowed in Ada 2012 mode and/or extensions allowed
|
-- we decide is allowed in Ada 2012 mode and/or extensions allowed
|
-- mode, the semantic analyzer may disallow one or both forms.
|
-- mode, the semantic analyzer may disallow one or both forms.
|
|
|
procedure Expand_Predicated_Loop (N : Node_Id) is
|
procedure Expand_Predicated_Loop (N : Node_Id) is
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Isc : constant Node_Id := Iteration_Scheme (N);
|
Isc : constant Node_Id := Iteration_Scheme (N);
|
LPS : constant Node_Id := Loop_Parameter_Specification (Isc);
|
LPS : constant Node_Id := Loop_Parameter_Specification (Isc);
|
Loop_Id : constant Entity_Id := Defining_Identifier (LPS);
|
Loop_Id : constant Entity_Id := Defining_Identifier (LPS);
|
Ltype : constant Entity_Id := Etype (Loop_Id);
|
Ltype : constant Entity_Id := Etype (Loop_Id);
|
Stat : constant List_Id := Static_Predicate (Ltype);
|
Stat : constant List_Id := Static_Predicate (Ltype);
|
Stmts : constant List_Id := Statements (N);
|
Stmts : constant List_Id := Statements (N);
|
|
|
begin
|
begin
|
-- Case of iteration over non-static predicate, should not be possible
|
-- Case of iteration over non-static predicate, should not be possible
|
-- since this is not allowed by the semantics and should have been
|
-- since this is not allowed by the semantics and should have been
|
-- caught during analysis of the loop statement.
|
-- caught during analysis of the loop statement.
|
|
|
if No (Stat) then
|
if No (Stat) then
|
raise Program_Error;
|
raise Program_Error;
|
|
|
-- If the predicate list is empty, that corresponds to a predicate of
|
-- If the predicate list is empty, that corresponds to a predicate of
|
-- False, in which case the loop won't run at all, and we rewrite the
|
-- False, in which case the loop won't run at all, and we rewrite the
|
-- entire loop as a null statement.
|
-- entire loop as a null statement.
|
|
|
elsif Is_Empty_List (Stat) then
|
elsif Is_Empty_List (Stat) then
|
Rewrite (N, Make_Null_Statement (Loc));
|
Rewrite (N, Make_Null_Statement (Loc));
|
Analyze (N);
|
Analyze (N);
|
|
|
-- For expansion over a static predicate we generate the following
|
-- For expansion over a static predicate we generate the following
|
|
|
-- declare
|
-- declare
|
-- J : Ltype := min-val;
|
-- J : Ltype := min-val;
|
-- begin
|
-- begin
|
-- loop
|
-- loop
|
-- body
|
-- body
|
-- case J is
|
-- case J is
|
-- when endpoint => J := startpoint;
|
-- when endpoint => J := startpoint;
|
-- when endpoint => J := startpoint;
|
-- when endpoint => J := startpoint;
|
-- ...
|
-- ...
|
-- when max-val => exit;
|
-- when max-val => exit;
|
-- when others => J := Lval'Succ (J);
|
-- when others => J := Lval'Succ (J);
|
-- end case;
|
-- end case;
|
-- end loop;
|
-- end loop;
|
-- end;
|
-- end;
|
|
|
-- To make this a little clearer, let's take a specific example:
|
-- To make this a little clearer, let's take a specific example:
|
|
|
-- type Int is range 1 .. 10;
|
-- type Int is range 1 .. 10;
|
-- subtype L is Int with
|
-- subtype L is Int with
|
-- predicate => L in 3 | 10 | 5 .. 7;
|
-- predicate => L in 3 | 10 | 5 .. 7;
|
-- ...
|
-- ...
|
-- for L in StaticP loop
|
-- for L in StaticP loop
|
-- Put_Line ("static:" & J'Img);
|
-- Put_Line ("static:" & J'Img);
|
-- end loop;
|
-- end loop;
|
|
|
-- In this case, the loop is transformed into
|
-- In this case, the loop is transformed into
|
|
|
-- begin
|
-- begin
|
-- J : L := 3;
|
-- J : L := 3;
|
-- loop
|
-- loop
|
-- body
|
-- body
|
-- case J is
|
-- case J is
|
-- when 3 => J := 5;
|
-- when 3 => J := 5;
|
-- when 7 => J := 10;
|
-- when 7 => J := 10;
|
-- when 10 => exit;
|
-- when 10 => exit;
|
-- when others => J := L'Succ (J);
|
-- when others => J := L'Succ (J);
|
-- end case;
|
-- end case;
|
-- end loop;
|
-- end loop;
|
-- end;
|
-- end;
|
|
|
else
|
else
|
Static_Predicate : declare
|
Static_Predicate : declare
|
S : Node_Id;
|
S : Node_Id;
|
D : Node_Id;
|
D : Node_Id;
|
P : Node_Id;
|
P : Node_Id;
|
Alts : List_Id;
|
Alts : List_Id;
|
Cstm : Node_Id;
|
Cstm : Node_Id;
|
|
|
function Lo_Val (N : Node_Id) return Node_Id;
|
function Lo_Val (N : Node_Id) return Node_Id;
|
-- Given static expression or static range, returns an identifier
|
-- Given static expression or static range, returns an identifier
|
-- whose value is the low bound of the expression value or range.
|
-- whose value is the low bound of the expression value or range.
|
|
|
function Hi_Val (N : Node_Id) return Node_Id;
|
function Hi_Val (N : Node_Id) return Node_Id;
|
-- Given static expression or static range, returns an identifier
|
-- Given static expression or static range, returns an identifier
|
-- whose value is the high bound of the expression value or range.
|
-- whose value is the high bound of the expression value or range.
|
|
|
------------
|
------------
|
-- Hi_Val --
|
-- Hi_Val --
|
------------
|
------------
|
|
|
function Hi_Val (N : Node_Id) return Node_Id is
|
function Hi_Val (N : Node_Id) return Node_Id is
|
begin
|
begin
|
if Is_Static_Expression (N) then
|
if Is_Static_Expression (N) then
|
return New_Copy (N);
|
return New_Copy (N);
|
else
|
else
|
pragma Assert (Nkind (N) = N_Range);
|
pragma Assert (Nkind (N) = N_Range);
|
return New_Copy (High_Bound (N));
|
return New_Copy (High_Bound (N));
|
end if;
|
end if;
|
end Hi_Val;
|
end Hi_Val;
|
|
|
------------
|
------------
|
-- Lo_Val --
|
-- Lo_Val --
|
------------
|
------------
|
|
|
function Lo_Val (N : Node_Id) return Node_Id is
|
function Lo_Val (N : Node_Id) return Node_Id is
|
begin
|
begin
|
if Is_Static_Expression (N) then
|
if Is_Static_Expression (N) then
|
return New_Copy (N);
|
return New_Copy (N);
|
else
|
else
|
pragma Assert (Nkind (N) = N_Range);
|
pragma Assert (Nkind (N) = N_Range);
|
return New_Copy (Low_Bound (N));
|
return New_Copy (Low_Bound (N));
|
end if;
|
end if;
|
end Lo_Val;
|
end Lo_Val;
|
|
|
-- Start of processing for Static_Predicate
|
-- Start of processing for Static_Predicate
|
|
|
begin
|
begin
|
-- Convert loop identifier to normal variable and reanalyze it so
|
-- Convert loop identifier to normal variable and reanalyze it so
|
-- that this conversion works. We have to use the same defining
|
-- that this conversion works. We have to use the same defining
|
-- identifier, since there may be references in the loop body.
|
-- identifier, since there may be references in the loop body.
|
|
|
Set_Analyzed (Loop_Id, False);
|
Set_Analyzed (Loop_Id, False);
|
Set_Ekind (Loop_Id, E_Variable);
|
Set_Ekind (Loop_Id, E_Variable);
|
|
|
-- Loop to create branches of case statement
|
-- Loop to create branches of case statement
|
|
|
Alts := New_List;
|
Alts := New_List;
|
P := First (Stat);
|
P := First (Stat);
|
while Present (P) loop
|
while Present (P) loop
|
if No (Next (P)) then
|
if No (Next (P)) then
|
S := Make_Exit_Statement (Loc);
|
S := Make_Exit_Statement (Loc);
|
else
|
else
|
S :=
|
S :=
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => New_Occurrence_Of (Loop_Id, Loc),
|
Name => New_Occurrence_Of (Loop_Id, Loc),
|
Expression => Lo_Val (Next (P)));
|
Expression => Lo_Val (Next (P)));
|
Set_Suppress_Assignment_Checks (S);
|
Set_Suppress_Assignment_Checks (S);
|
end if;
|
end if;
|
|
|
Append_To (Alts,
|
Append_To (Alts,
|
Make_Case_Statement_Alternative (Loc,
|
Make_Case_Statement_Alternative (Loc,
|
Statements => New_List (S),
|
Statements => New_List (S),
|
Discrete_Choices => New_List (Hi_Val (P))));
|
Discrete_Choices => New_List (Hi_Val (P))));
|
|
|
Next (P);
|
Next (P);
|
end loop;
|
end loop;
|
|
|
-- Add others choice
|
-- Add others choice
|
|
|
S :=
|
S :=
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name => New_Occurrence_Of (Loop_Id, Loc),
|
Name => New_Occurrence_Of (Loop_Id, Loc),
|
Expression =>
|
Expression =>
|
Make_Attribute_Reference (Loc,
|
Make_Attribute_Reference (Loc,
|
Prefix => New_Occurrence_Of (Ltype, Loc),
|
Prefix => New_Occurrence_Of (Ltype, Loc),
|
Attribute_Name => Name_Succ,
|
Attribute_Name => Name_Succ,
|
Expressions => New_List (
|
Expressions => New_List (
|
New_Occurrence_Of (Loop_Id, Loc))));
|
New_Occurrence_Of (Loop_Id, Loc))));
|
Set_Suppress_Assignment_Checks (S);
|
Set_Suppress_Assignment_Checks (S);
|
|
|
Append_To (Alts,
|
Append_To (Alts,
|
Make_Case_Statement_Alternative (Loc,
|
Make_Case_Statement_Alternative (Loc,
|
Discrete_Choices => New_List (Make_Others_Choice (Loc)),
|
Discrete_Choices => New_List (Make_Others_Choice (Loc)),
|
Statements => New_List (S)));
|
Statements => New_List (S)));
|
|
|
-- Construct case statement and append to body statements
|
-- Construct case statement and append to body statements
|
|
|
Cstm :=
|
Cstm :=
|
Make_Case_Statement (Loc,
|
Make_Case_Statement (Loc,
|
Expression => New_Occurrence_Of (Loop_Id, Loc),
|
Expression => New_Occurrence_Of (Loop_Id, Loc),
|
Alternatives => Alts);
|
Alternatives => Alts);
|
Append_To (Stmts, Cstm);
|
Append_To (Stmts, Cstm);
|
|
|
-- Rewrite the loop
|
-- Rewrite the loop
|
|
|
D :=
|
D :=
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Loop_Id,
|
Defining_Identifier => Loop_Id,
|
Object_Definition => New_Occurrence_Of (Ltype, Loc),
|
Object_Definition => New_Occurrence_Of (Ltype, Loc),
|
Expression => Lo_Val (First (Stat)));
|
Expression => Lo_Val (First (Stat)));
|
Set_Suppress_Assignment_Checks (D);
|
Set_Suppress_Assignment_Checks (D);
|
|
|
Rewrite (N,
|
Rewrite (N,
|
Make_Block_Statement (Loc,
|
Make_Block_Statement (Loc,
|
Declarations => New_List (D),
|
Declarations => New_List (D),
|
Handled_Statement_Sequence =>
|
Handled_Statement_Sequence =>
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Make_Handled_Sequence_Of_Statements (Loc,
|
Statements => New_List (
|
Statements => New_List (
|
Make_Loop_Statement (Loc,
|
Make_Loop_Statement (Loc,
|
Statements => Stmts,
|
Statements => Stmts,
|
End_Label => Empty)))));
|
End_Label => Empty)))));
|
|
|
Analyze (N);
|
Analyze (N);
|
end Static_Predicate;
|
end Static_Predicate;
|
end if;
|
end if;
|
end Expand_Predicated_Loop;
|
end Expand_Predicated_Loop;
|
|
|
------------------------------
|
------------------------------
|
-- Make_Tag_Ctrl_Assignment --
|
-- Make_Tag_Ctrl_Assignment --
|
------------------------------
|
------------------------------
|
|
|
function Make_Tag_Ctrl_Assignment (N : Node_Id) return List_Id is
|
function Make_Tag_Ctrl_Assignment (N : Node_Id) return List_Id is
|
Asn : constant Node_Id := Relocate_Node (N);
|
Asn : constant Node_Id := Relocate_Node (N);
|
L : constant Node_Id := Name (N);
|
L : constant Node_Id := Name (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Loc : constant Source_Ptr := Sloc (N);
|
Res : constant List_Id := New_List;
|
Res : constant List_Id := New_List;
|
T : constant Entity_Id := Underlying_Type (Etype (L));
|
T : constant Entity_Id := Underlying_Type (Etype (L));
|
|
|
Comp_Asn : constant Boolean := Is_Fully_Repped_Tagged_Type (T);
|
Comp_Asn : constant Boolean := Is_Fully_Repped_Tagged_Type (T);
|
Ctrl_Act : constant Boolean := Needs_Finalization (T)
|
Ctrl_Act : constant Boolean := Needs_Finalization (T)
|
and then not No_Ctrl_Actions (N);
|
and then not No_Ctrl_Actions (N);
|
Save_Tag : constant Boolean := Is_Tagged_Type (T)
|
Save_Tag : constant Boolean := Is_Tagged_Type (T)
|
and then not Comp_Asn
|
and then not Comp_Asn
|
and then not No_Ctrl_Actions (N)
|
and then not No_Ctrl_Actions (N)
|
and then Tagged_Type_Expansion;
|
and then Tagged_Type_Expansion;
|
-- Tags are not saved and restored when VM_Target because VM tags are
|
-- Tags are not saved and restored when VM_Target because VM tags are
|
-- represented implicitly in objects.
|
-- represented implicitly in objects.
|
|
|
Next_Id : Entity_Id;
|
Next_Id : Entity_Id;
|
Prev_Id : Entity_Id;
|
Prev_Id : Entity_Id;
|
Tag_Id : Entity_Id;
|
Tag_Id : Entity_Id;
|
|
|
begin
|
begin
|
-- Finalize the target of the assignment when controlled
|
-- Finalize the target of the assignment when controlled
|
|
|
-- We have two exceptions here:
|
-- We have two exceptions here:
|
|
|
-- 1. If we are in an init proc since it is an initialization more
|
-- 1. If we are in an init proc since it is an initialization more
|
-- than an assignment.
|
-- than an assignment.
|
|
|
-- 2. If the left-hand side is a temporary that was not initialized
|
-- 2. If the left-hand side is a temporary that was not initialized
|
-- (or the parent part of a temporary since it is the case in
|
-- (or the parent part of a temporary since it is the case in
|
-- extension aggregates). Such a temporary does not come from
|
-- extension aggregates). Such a temporary does not come from
|
-- source. We must examine the original node for the prefix, because
|
-- source. We must examine the original node for the prefix, because
|
-- it may be a component of an entry formal, in which case it has
|
-- it may be a component of an entry formal, in which case it has
|
-- been rewritten and does not appear to come from source either.
|
-- been rewritten and does not appear to come from source either.
|
|
|
-- Case of init proc
|
-- Case of init proc
|
|
|
if not Ctrl_Act then
|
if not Ctrl_Act then
|
null;
|
null;
|
|
|
-- The left hand side is an uninitialized temporary object
|
-- The left hand side is an uninitialized temporary object
|
|
|
elsif Nkind (L) = N_Type_Conversion
|
elsif Nkind (L) = N_Type_Conversion
|
and then Is_Entity_Name (Expression (L))
|
and then Is_Entity_Name (Expression (L))
|
and then Nkind (Parent (Entity (Expression (L)))) =
|
and then Nkind (Parent (Entity (Expression (L)))) =
|
N_Object_Declaration
|
N_Object_Declaration
|
and then No_Initialization (Parent (Entity (Expression (L))))
|
and then No_Initialization (Parent (Entity (Expression (L))))
|
then
|
then
|
null;
|
null;
|
|
|
else
|
else
|
Append_To (Res,
|
Append_To (Res,
|
Make_Final_Call
|
Make_Final_Call
|
(Obj_Ref => Duplicate_Subexpr_No_Checks (L),
|
(Obj_Ref => Duplicate_Subexpr_No_Checks (L),
|
Typ => Etype (L)));
|
Typ => Etype (L)));
|
end if;
|
end if;
|
|
|
-- Save the Tag in a local variable Tag_Id
|
-- Save the Tag in a local variable Tag_Id
|
|
|
if Save_Tag then
|
if Save_Tag then
|
Tag_Id := Make_Temporary (Loc, 'A');
|
Tag_Id := Make_Temporary (Loc, 'A');
|
|
|
Append_To (Res,
|
Append_To (Res,
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Tag_Id,
|
Defining_Identifier => Tag_Id,
|
Object_Definition => New_Reference_To (RTE (RE_Tag), Loc),
|
Object_Definition => New_Reference_To (RTE (RE_Tag), Loc),
|
Expression =>
|
Expression =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr_No_Checks (L),
|
Prefix => Duplicate_Subexpr_No_Checks (L),
|
Selector_Name =>
|
Selector_Name =>
|
New_Reference_To (First_Tag_Component (T), Loc))));
|
New_Reference_To (First_Tag_Component (T), Loc))));
|
|
|
-- Otherwise Tag_Id is not used
|
-- Otherwise Tag_Id is not used
|
|
|
else
|
else
|
Tag_Id := Empty;
|
Tag_Id := Empty;
|
end if;
|
end if;
|
|
|
-- Save the Prev and Next fields on .NET/JVM. This is not needed on non
|
-- Save the Prev and Next fields on .NET/JVM. This is not needed on non
|
-- VM targets since the fields are not part of the object.
|
-- VM targets since the fields are not part of the object.
|
|
|
if VM_Target /= No_VM
|
if VM_Target /= No_VM
|
and then Is_Controlled (T)
|
and then Is_Controlled (T)
|
then
|
then
|
Prev_Id := Make_Temporary (Loc, 'P');
|
Prev_Id := Make_Temporary (Loc, 'P');
|
Next_Id := Make_Temporary (Loc, 'N');
|
Next_Id := Make_Temporary (Loc, 'N');
|
|
|
-- Generate:
|
-- Generate:
|
-- Pnn : Root_Controlled_Ptr := Root_Controlled (L).Prev;
|
-- Pnn : Root_Controlled_Ptr := Root_Controlled (L).Prev;
|
|
|
Append_To (Res,
|
Append_To (Res,
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Prev_Id,
|
Defining_Identifier => Prev_Id,
|
Object_Definition =>
|
Object_Definition =>
|
New_Reference_To (RTE (RE_Root_Controlled_Ptr), Loc),
|
New_Reference_To (RTE (RE_Root_Controlled_Ptr), Loc),
|
Expression =>
|
Expression =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix =>
|
Prefix =>
|
Unchecked_Convert_To
|
Unchecked_Convert_To
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Name_Prev))));
|
Make_Identifier (Loc, Name_Prev))));
|
|
|
-- Generate:
|
-- Generate:
|
-- Nnn : Root_Controlled_Ptr := Root_Controlled (L).Next;
|
-- Nnn : Root_Controlled_Ptr := Root_Controlled (L).Next;
|
|
|
Append_To (Res,
|
Append_To (Res,
|
Make_Object_Declaration (Loc,
|
Make_Object_Declaration (Loc,
|
Defining_Identifier => Next_Id,
|
Defining_Identifier => Next_Id,
|
Object_Definition =>
|
Object_Definition =>
|
New_Reference_To (RTE (RE_Root_Controlled_Ptr), Loc),
|
New_Reference_To (RTE (RE_Root_Controlled_Ptr), Loc),
|
Expression =>
|
Expression =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix =>
|
Prefix =>
|
Unchecked_Convert_To
|
Unchecked_Convert_To
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Name_Next))));
|
Make_Identifier (Loc, Name_Next))));
|
end if;
|
end if;
|
|
|
-- If the tagged type has a full rep clause, expand the assignment into
|
-- If the tagged type has a full rep clause, expand the assignment into
|
-- component-wise assignments. Mark the node as unanalyzed in order to
|
-- component-wise assignments. Mark the node as unanalyzed in order to
|
-- generate the proper code and propagate this scenario by setting a
|
-- generate the proper code and propagate this scenario by setting a
|
-- flag to avoid infinite recursion.
|
-- flag to avoid infinite recursion.
|
|
|
if Comp_Asn then
|
if Comp_Asn then
|
Set_Analyzed (Asn, False);
|
Set_Analyzed (Asn, False);
|
Set_Componentwise_Assignment (Asn, True);
|
Set_Componentwise_Assignment (Asn, True);
|
end if;
|
end if;
|
|
|
Append_To (Res, Asn);
|
Append_To (Res, Asn);
|
|
|
-- Restore the tag
|
-- Restore the tag
|
|
|
if Save_Tag then
|
if Save_Tag then
|
Append_To (Res,
|
Append_To (Res,
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name =>
|
Name =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix => Duplicate_Subexpr_No_Checks (L),
|
Prefix => Duplicate_Subexpr_No_Checks (L),
|
Selector_Name =>
|
Selector_Name =>
|
New_Reference_To (First_Tag_Component (T), Loc)),
|
New_Reference_To (First_Tag_Component (T), Loc)),
|
Expression => New_Reference_To (Tag_Id, Loc)));
|
Expression => New_Reference_To (Tag_Id, Loc)));
|
end if;
|
end if;
|
|
|
-- Restore the Prev and Next fields on .NET/JVM
|
-- Restore the Prev and Next fields on .NET/JVM
|
|
|
if VM_Target /= No_VM
|
if VM_Target /= No_VM
|
and then Is_Controlled (T)
|
and then Is_Controlled (T)
|
then
|
then
|
-- Generate:
|
-- Generate:
|
-- Root_Controlled (L).Prev := Prev_Id;
|
-- Root_Controlled (L).Prev := Prev_Id;
|
|
|
Append_To (Res,
|
Append_To (Res,
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name =>
|
Name =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix =>
|
Prefix =>
|
Unchecked_Convert_To
|
Unchecked_Convert_To
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
Selector_Name =>
|
Selector_Name =>
|
Make_Identifier (Loc, Name_Prev)),
|
Make_Identifier (Loc, Name_Prev)),
|
Expression => New_Reference_To (Prev_Id, Loc)));
|
Expression => New_Reference_To (Prev_Id, Loc)));
|
|
|
-- Generate:
|
-- Generate:
|
-- Root_Controlled (L).Next := Next_Id;
|
-- Root_Controlled (L).Next := Next_Id;
|
|
|
Append_To (Res,
|
Append_To (Res,
|
Make_Assignment_Statement (Loc,
|
Make_Assignment_Statement (Loc,
|
Name =>
|
Name =>
|
Make_Selected_Component (Loc,
|
Make_Selected_Component (Loc,
|
Prefix =>
|
Prefix =>
|
Unchecked_Convert_To
|
Unchecked_Convert_To
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
(RTE (RE_Root_Controlled), New_Copy_Tree (L)),
|
Selector_Name => Make_Identifier (Loc, Name_Next)),
|
Selector_Name => Make_Identifier (Loc, Name_Next)),
|
Expression => New_Reference_To (Next_Id, Loc)));
|
Expression => New_Reference_To (Next_Id, Loc)));
|
end if;
|
end if;
|
|
|
-- Adjust the target after the assignment when controlled (not in the
|
-- Adjust the target after the assignment when controlled (not in the
|
-- init proc since it is an initialization more than an assignment).
|
-- init proc since it is an initialization more than an assignment).
|
|
|
if Ctrl_Act then
|
if Ctrl_Act then
|
Append_To (Res,
|
Append_To (Res,
|
Make_Adjust_Call
|
Make_Adjust_Call
|
(Obj_Ref => Duplicate_Subexpr_Move_Checks (L),
|
(Obj_Ref => Duplicate_Subexpr_Move_Checks (L),
|
Typ => Etype (L)));
|
Typ => Etype (L)));
|
end if;
|
end if;
|
|
|
return Res;
|
return Res;
|
|
|
exception
|
exception
|
|
|
-- Could use comment here ???
|
-- Could use comment here ???
|
|
|
when RE_Not_Available =>
|
when RE_Not_Available =>
|
return Empty_List;
|
return Empty_List;
|
end Make_Tag_Ctrl_Assignment;
|
end Make_Tag_Ctrl_Assignment;
|
|
|
end Exp_Ch5;
|
end Exp_Ch5;
|
|
|