source: src/GenPoly/Lvalue.cc@ 4389966

ADT aaron-thesis arm-eh ast-experimental cleanup-dtors ctor deferred_resn demangler enum forall-pointer-decay gc_noraii jacob/cs343-translation jenkins-sandbox memory new-ast new-ast-unique-expr new-env no_list persistent-indexer pthread-emulation qualifiedEnum resolv-new string with_gc
Last change on this file since 4389966 was 4389966, checked in by Peter A. Buhr <pabuhr@…>, 10 years ago

fix comment
  • Property mode set to 100644
File size: 4.9 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// Lvalue.cc --
8//
9// Author : Richard C. Bilson
10// Created On : Mon May 18 07:44:20 2015
11// Last Modified By : Peter A. Buhr
12// Last Modified On : Tue Dec 15 15:33:13 2015
13// Update Count : 3
14//
15
16#include <cassert>
17
18#include "Lvalue.h"
19
20#include "SynTree/Declaration.h"
21#include "SynTree/Type.h"
22#include "SynTree/Expression.h"
23#include "SynTree/Statement.h"
24#include "SynTree/Visitor.h"
25#include "SynTree/Mutator.h"
26#include "SymTab/Indexer.h"
27#include "ResolvExpr/Resolver.h"
28#include "ResolvExpr/typeops.h"
29
30#include "UniqueName.h"
31#include "utility.h"
32
33namespace GenPoly {
34 namespace {
35 const std::list<Label> noLabels;
36
37 /// Replace uses of lvalue returns with appropriate pointers
38 class Pass1 : public Mutator {
39 public:
40 Pass1();
41
42 virtual Expression *mutate( ApplicationExpr *appExpr );
43 virtual Statement *mutate( ReturnStmt *appExpr );
44 virtual DeclarationWithType *mutate( FunctionDecl *funDecl );
45 private:
46 DeclarationWithType* retval;
47 };
48
49 /// Replace declarations of lvalue returns with appropriate pointers
50 class Pass2 : public Visitor {
51 public:
52 virtual void visit( FunctionType *funType );
53 private:
54 };
55 } // namespace
56
57 void convertLvalue( std::list< Declaration* >& translationUnit ) {
58 Pass1 p1;
59 Pass2 p2;
60 mutateAll( translationUnit, p1 );
61 acceptAll( translationUnit, p2 );
62 }
63
64 namespace {
65 bool isLvalueRet( FunctionType *function ) {
66 if ( ! function->get_returnVals().empty() ) {
67 return function->get_returnVals().front()->get_type()->get_isLvalue();
68 } else {
69 return false;
70 } // if
71 }
72
73 bool isIntrinsicApp( ApplicationExpr *appExpr ) {
74 if ( VariableExpr *varExpr = dynamic_cast< VariableExpr* >( appExpr->get_function() ) ) {
75 return varExpr->get_var()->get_linkage() == LinkageSpec::Intrinsic;
76 } else {
77 return false;
78 } // if
79 }
80
81 Pass1::Pass1() {
82 }
83
84 DeclarationWithType * Pass1::mutate( FunctionDecl *funcDecl ) {
85 if ( funcDecl->get_statements() ) {
86 DeclarationWithType* oldRetval = retval;
87 retval = 0;
88 if ( ! LinkageSpec::isBuiltin( funcDecl->get_linkage() ) && isLvalueRet( funcDecl->get_functionType() ) ) {
89 retval = funcDecl->get_functionType()->get_returnVals().front();
90 }
91 // fix expressions and return statements in this function
92 funcDecl->set_statements( funcDecl->get_statements()->acceptMutator( *this ) );
93 retval = oldRetval;
94 } // if
95 return funcDecl;
96 }
97
98 Expression * Pass1::mutate( ApplicationExpr *appExpr ) {
99 appExpr->get_function()->acceptMutator( *this );
100 mutateAll( appExpr->get_args(), *this );
101
102 assert( ! appExpr->get_function()->get_results().empty() );
103
104 PointerType *pointer = dynamic_cast< PointerType* >( appExpr->get_function()->get_results().front() );
105 assert( pointer );
106 FunctionType *function = dynamic_cast< FunctionType* >( pointer->get_base() );
107 assert( function );
108
109 std::string typeName;
110 if ( isLvalueRet( function ) && ! isIntrinsicApp( appExpr ) ) {
111 UntypedExpr *deref = new UntypedExpr( new NameExpr( "*?" ) );
112 deref->get_results().push_back( appExpr->get_results().front() );
113 appExpr->get_results().front() = new PointerType( Type::Qualifiers(), deref->get_results().front()->clone() );
114 deref->get_args().push_back( appExpr );
115 return deref;
116 } else {
117 return appExpr;
118 } // if
119 }
120
121 Statement * Pass1::mutate(ReturnStmt *retStmt) {
122 if ( retval && retStmt->get_expr() ) {
123 assert( ! retStmt->get_expr()->get_results().empty() );
124 if ( retStmt->get_expr()->get_results().front()->get_isLvalue() ) {
125 // ***** Code Removal ***** because casts may be stripped already
126
127 // strip casts because not allowed to take address of cast
128 // while ( CastExpr *castExpr = dynamic_cast< CastExpr* >( retStmt->get_expr() ) ) {
129 // retStmt->set_expr( castExpr->get_arg() );
130 // retStmt->get_expr()->set_env( castExpr->get_env() );
131 // castExpr->set_env( 0 );
132 // castExpr->set_arg( 0 );
133 // delete castExpr;
134 // } // while
135 retStmt->set_expr( new AddressExpr( retStmt->get_expr()->acceptMutator( *this ) ) );
136 } else {
137 throw SemanticError( "Attempt to return non-lvalue from an lvalue-qualified function" );
138 } // if
139 } // if
140 return retStmt;
141 }
142
143 void Pass2::visit( FunctionType *funType ) {
144 std::string typeName;
145 if ( isLvalueRet( funType ) ) {
146 DeclarationWithType *retParm = funType->get_returnVals().front();
147
148 // make a new parameter that is a pointer to the type of the old return value
149 retParm->set_type( new PointerType( Type::Qualifiers(), retParm->get_type() ) );
150 } // if
151
152 Visitor::visit( funType );
153 }
154 } // namespace
155} // namespace GenPoly
156
157// Local Variables: //
158// tab-width: 4 //
159// mode: c++ //
160// compile-command: "make install" //
161// End: //
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