1 | // |
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2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo |
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3 | // |
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4 | // The contents of this file are covered under the licence agreement in the |
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5 | // file "LICENCE" distributed with Cforall. |
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6 | // |
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7 | // Resolver.cc -- |
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8 | // |
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9 | // Author : Richard C. Bilson |
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10 | // Created On : Sun May 17 12:17:01 2015 |
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11 | // Last Modified By : Peter A. Buhr |
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12 | // Last Modified On : Sat Feb 17 11:19:40 2018 |
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13 | // Update Count : 213 |
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14 | // |
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15 | |
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16 | #include <stddef.h> // for NULL |
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17 | #include <cassert> // for strict_dynamic_cast, assert |
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18 | #include <memory> // for allocator, allocator_traits<... |
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19 | #include <tuple> // for get |
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20 | #include <vector> |
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21 | |
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22 | #include "Alternative.h" // for Alternative, AltList |
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23 | #include "AlternativeFinder.h" // for AlternativeFinder, resolveIn... |
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24 | #include "Common/PassVisitor.h" // for PassVisitor |
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25 | #include "Common/SemanticError.h" // for SemanticError |
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26 | #include "Common/utility.h" // for ValueGuard, group_iterate |
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27 | #include "CurrentObject.h" // for CurrentObject |
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28 | #include "InitTweak/GenInit.h" |
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29 | #include "InitTweak/InitTweak.h" // for isIntrinsicSingleArgCallStmt |
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30 | #include "RenameVars.h" // for RenameVars, global_renamer |
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31 | #include "ResolvExpr/TypeEnvironment.h" // for TypeEnvironment |
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32 | #include "ResolveTypeof.h" // for resolveTypeof |
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33 | #include "Resolver.h" |
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34 | #include "SymTab/Autogen.h" // for SizeType |
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35 | #include "SymTab/Indexer.h" // for Indexer |
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36 | #include "SynTree/Declaration.h" // for ObjectDecl, TypeDecl, Declar... |
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37 | #include "SynTree/Expression.h" // for Expression, CastExpr, InitExpr |
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38 | #include "SynTree/Initializer.h" // for ConstructorInit, SingleInit |
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39 | #include "SynTree/Statement.h" // for ForStmt, Statement, BranchStmt |
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40 | #include "SynTree/Type.h" // for Type, BasicType, PointerType |
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41 | #include "SynTree/TypeSubstitution.h" // for TypeSubstitution |
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42 | #include "SynTree/Visitor.h" // for acceptAll, maybeAccept |
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43 | #include "Tuples/Tuples.h" |
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44 | #include "typeops.h" // for extractResultType |
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45 | #include "Unify.h" // for unify |
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46 | |
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47 | using namespace std; |
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48 | |
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49 | namespace ResolvExpr { |
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50 | struct Resolver final : public WithIndexer, public WithGuards, public WithVisitorRef<Resolver>, public WithShortCircuiting, public WithStmtsToAdd { |
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51 | Resolver() {} |
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52 | Resolver( const SymTab::Indexer & other ) { |
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53 | indexer = other; |
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54 | } |
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55 | |
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56 | void previsit( FunctionDecl *functionDecl ); |
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57 | void postvisit( FunctionDecl *functionDecl ); |
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58 | void previsit( ObjectDecl *objectDecll ); |
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59 | void previsit( TypeDecl *typeDecl ); |
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60 | void previsit( EnumDecl * enumDecl ); |
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61 | void previsit( StaticAssertDecl * assertDecl ); |
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62 | |
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63 | void previsit( ArrayType * at ); |
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64 | void previsit( PointerType * at ); |
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65 | |
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66 | void previsit( ExprStmt *exprStmt ); |
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67 | void previsit( AsmExpr *asmExpr ); |
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68 | void previsit( AsmStmt *asmStmt ); |
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69 | void previsit( IfStmt *ifStmt ); |
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70 | void previsit( WhileStmt *whileStmt ); |
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71 | void previsit( ForStmt *forStmt ); |
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72 | void previsit( SwitchStmt *switchStmt ); |
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73 | void previsit( CaseStmt *caseStmt ); |
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74 | void previsit( BranchStmt *branchStmt ); |
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75 | void previsit( ReturnStmt *returnStmt ); |
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76 | void previsit( ThrowStmt *throwStmt ); |
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77 | void previsit( CatchStmt *catchStmt ); |
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78 | void previsit( WaitForStmt * stmt ); |
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79 | void previsit( WithStmt * withStmt ); |
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80 | |
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81 | void previsit( SingleInit *singleInit ); |
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82 | void previsit( ListInit *listInit ); |
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83 | void previsit( ConstructorInit *ctorInit ); |
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84 | private: |
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85 | typedef std::list< Initializer * >::iterator InitIterator; |
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86 | |
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87 | template< typename PtrType > |
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88 | void handlePtrType( PtrType * type ); |
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89 | |
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90 | void resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts ); |
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91 | void fallbackInit( ConstructorInit * ctorInit ); |
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92 | |
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93 | Type * functionReturn = nullptr; |
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94 | CurrentObject currentObject = nullptr; |
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95 | bool inEnumDecl = false; |
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96 | }; |
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97 | |
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98 | void resolve( std::list< Declaration * > translationUnit ) { |
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99 | PassVisitor<Resolver> resolver; |
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100 | acceptAll( translationUnit, resolver ); |
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101 | } |
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102 | |
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103 | void resolveDecl( Declaration * decl, const SymTab::Indexer &indexer ) { |
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104 | PassVisitor<Resolver> resolver( indexer ); |
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105 | maybeAccept( decl, resolver ); |
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106 | } |
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107 | |
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108 | namespace { |
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109 | struct DeleteFinder : public WithShortCircuiting { |
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110 | DeletedExpr * delExpr = nullptr; |
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111 | void previsit( DeletedExpr * expr ) { |
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112 | if ( delExpr ) visit_children = false; |
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113 | else delExpr = expr; |
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114 | } |
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115 | |
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116 | void previsit( Expression * ) { |
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117 | if ( delExpr ) visit_children = false; |
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118 | } |
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119 | }; |
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120 | } |
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121 | |
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122 | DeletedExpr * findDeletedExpr( Expression * expr ) { |
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123 | PassVisitor<DeleteFinder> finder; |
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124 | expr->accept( finder ); |
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125 | return finder.pass.delExpr; |
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126 | } |
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127 | |
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128 | namespace { |
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129 | void finishExpr( Expression *expr, const TypeEnvironment &env, TypeSubstitution * oldenv = nullptr ) { |
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130 | expr->env = oldenv ? oldenv->clone() : new TypeSubstitution; |
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131 | env.makeSubstitution( *expr->get_env() ); |
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132 | } |
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133 | |
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134 | void removeExtraneousCast( Expression *& expr, const SymTab::Indexer & indexer ) { |
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135 | if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( expr ) ) { |
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136 | if ( ResolvExpr::typesCompatible( castExpr->arg->result, castExpr->result, indexer ) ) { |
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137 | // cast is to the same type as its argument, so it's unnecessary -- remove it |
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138 | expr = castExpr->arg; |
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139 | castExpr->arg = nullptr; |
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140 | std::swap( expr->env, castExpr->env ); |
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141 | delete castExpr; |
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142 | } |
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143 | } |
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144 | } |
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145 | } // namespace |
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146 | |
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147 | namespace { |
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148 | void findUnfinishedKindExpression(Expression * untyped, Alternative & alt, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, bool adjust = false, bool prune = true, bool failFast = true) { |
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149 | assertf( untyped, "expected a non-null expression." ); |
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150 | TypeEnvironment env; |
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151 | AlternativeFinder finder( indexer, env ); |
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152 | finder.find( untyped, adjust, prune, failFast ); |
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153 | |
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154 | #if 0 |
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155 | if ( finder.get_alternatives().size() != 1 ) { |
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156 | std::cerr << "untyped expr is "; |
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157 | untyped->print( std::cerr ); |
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158 | std::cerr << std::endl << "alternatives are:"; |
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159 | for ( const Alternative & alt : finder.get_alternatives() ) { |
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160 | alt.print( std::cerr ); |
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161 | } // for |
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162 | } // if |
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163 | #endif |
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164 | |
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165 | AltList candidates; |
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166 | for ( Alternative & alt : finder.get_alternatives() ) { |
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167 | if ( pred( alt ) ) { |
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168 | candidates.push_back( std::move( alt ) ); |
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169 | } |
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170 | } |
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171 | |
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172 | // xxx - if > 1 alternative with same cost, ignore deleted and pick from remaining |
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173 | // choose the lowest cost expression among the candidates |
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174 | AltList winners; |
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175 | findMinCost( candidates.begin(), candidates.end(), back_inserter( winners ) ); |
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176 | if ( winners.size() == 0 ) { |
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177 | SemanticError( untyped, toString( "No reasonable alternatives for ", kindStr, (kindStr != "" ? " " : ""), "expression: ") ); |
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178 | } else if ( winners.size() != 1 ) { |
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179 | std::ostringstream stream; |
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180 | stream << "Cannot choose between " << winners.size() << " alternatives for " << kindStr << (kindStr != "" ? " " : "") << "expression\n"; |
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181 | untyped->print( stream ); |
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182 | stream << " Alternatives are:\n"; |
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183 | printAlts( winners, stream, 1 ); |
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184 | SemanticError( untyped->location, stream.str() ); |
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185 | } |
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186 | |
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187 | // there is one unambiguous interpretation - move the expression into the with statement |
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188 | Alternative & choice = winners.front(); |
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189 | if ( findDeletedExpr( choice.expr ) ) { |
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190 | SemanticError( choice.expr, "Unique best alternative includes deleted identifier in " ); |
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191 | } |
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192 | alt = std::move( choice ); |
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193 | } |
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194 | |
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195 | /// resolve `untyped` to the expression whose alternative satisfies `pred` with the lowest cost; kindStr is used for providing better error messages |
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196 | void findKindExpression(Expression *& untyped, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, bool adjust = false, bool prune = true, bool failFast = true) { |
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197 | if ( ! untyped ) return; |
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198 | Alternative choice; |
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199 | findUnfinishedKindExpression( untyped, choice, indexer, kindStr, pred, adjust, prune, failFast ); |
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200 | finishExpr( choice.expr, choice.env, untyped->env ); |
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201 | delete untyped; |
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202 | untyped = choice.expr; |
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203 | choice.expr = nullptr; |
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204 | } |
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205 | |
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206 | bool standardAlternativeFilter( const Alternative & ) { |
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207 | // currently don't need to filter, under normal circumstances. |
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208 | // in the future, this may be useful for removing deleted expressions |
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209 | return true; |
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210 | } |
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211 | } // namespace |
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212 | |
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213 | // used in resolveTypeof |
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214 | Expression * resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer ) { |
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215 | TypeEnvironment env; |
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216 | return resolveInVoidContext( expr, indexer, env ); |
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217 | } |
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218 | |
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219 | Expression * resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer, TypeEnvironment &env ) { |
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220 | // it's a property of the language that a cast expression has either 1 or 0 interpretations; if it has 0 |
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221 | // interpretations, an exception has already been thrown. |
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222 | assertf( expr, "expected a non-null expression." ); |
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223 | |
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224 | static CastExpr untyped( nullptr ); // cast to void |
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225 | |
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226 | // set up and resolve expression cast to void |
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227 | untyped.arg = expr; |
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228 | Alternative choice; |
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229 | findUnfinishedKindExpression( &untyped, choice, indexer, "", standardAlternativeFilter, true ); |
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230 | CastExpr * castExpr = strict_dynamic_cast< CastExpr * >( choice.expr ); |
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231 | env = std::move( choice.env ); |
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232 | |
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233 | // clean up resolved expression |
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234 | Expression * ret = castExpr->arg; |
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235 | castExpr->arg = nullptr; |
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236 | |
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237 | // unlink the arg so that it isn't deleted twice at the end of the program |
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238 | untyped.arg = nullptr; |
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239 | return ret; |
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240 | } |
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241 | |
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242 | void findVoidExpression( Expression *& untyped, const SymTab::Indexer &indexer ) { |
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243 | resetTyVarRenaming(); |
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244 | TypeEnvironment env; |
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245 | Expression * newExpr = resolveInVoidContext( untyped, indexer, env ); |
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246 | finishExpr( newExpr, env, untyped->env ); |
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247 | delete untyped; |
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248 | untyped = newExpr; |
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249 | } |
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250 | |
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251 | void findSingleExpression( Expression *&untyped, const SymTab::Indexer &indexer ) { |
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252 | findKindExpression( untyped, indexer, "", standardAlternativeFilter ); |
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253 | } |
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254 | |
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255 | void findSingleExpression( Expression *& untyped, Type * type, const SymTab::Indexer & indexer ) { |
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256 | assert( untyped && type ); |
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257 | untyped = new CastExpr( untyped, type ); |
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258 | findSingleExpression( untyped, indexer ); |
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259 | removeExtraneousCast( untyped, indexer ); |
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260 | } |
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261 | |
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262 | namespace { |
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263 | bool isIntegralType( const Alternative & alt ) { |
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264 | Type * type = alt.expr->result; |
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265 | if ( dynamic_cast< EnumInstType * >( type ) ) { |
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266 | return true; |
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267 | } else if ( BasicType *bt = dynamic_cast< BasicType * >( type ) ) { |
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268 | return bt->isInteger(); |
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269 | } else if ( dynamic_cast< ZeroType* >( type ) != nullptr || dynamic_cast< OneType* >( type ) != nullptr ) { |
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270 | return true; |
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271 | } else { |
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272 | return false; |
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273 | } // if |
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274 | } |
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275 | |
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276 | void findIntegralExpression( Expression *& untyped, const SymTab::Indexer &indexer ) { |
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277 | findKindExpression( untyped, indexer, "condition", isIntegralType ); |
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278 | } |
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279 | } |
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280 | |
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281 | void Resolver::previsit( ObjectDecl *objectDecl ) { |
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282 | Type *new_type = resolveTypeof( objectDecl->get_type(), indexer ); |
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283 | objectDecl->set_type( new_type ); |
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284 | // To handle initialization of routine pointers, e.g., int (*fp)(int) = foo(), means that class-variable |
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285 | // initContext is changed multiple time because the LHS is analysed twice. The second analysis changes |
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286 | // initContext because of a function type can contain object declarations in the return and parameter types. So |
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287 | // each value of initContext is retained, so the type on the first analysis is preserved and used for selecting |
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288 | // the RHS. |
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289 | GuardValue( currentObject ); |
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290 | currentObject = CurrentObject( objectDecl->get_type() ); |
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291 | if ( inEnumDecl && dynamic_cast< EnumInstType * >( objectDecl->get_type() ) ) { |
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292 | // enumerator initializers should not use the enum type to initialize, since |
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293 | // the enum type is still incomplete at this point. Use signed int instead. |
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294 | currentObject = CurrentObject( new BasicType( Type::Qualifiers(), BasicType::SignedInt ) ); |
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295 | } |
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296 | } |
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297 | |
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298 | template< typename PtrType > |
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299 | void Resolver::handlePtrType( PtrType * type ) { |
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300 | if ( type->get_dimension() ) { |
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301 | findSingleExpression( type->dimension, SymTab::SizeType->clone(), indexer ); |
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302 | } |
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303 | } |
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304 | |
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305 | void Resolver::previsit( ArrayType * at ) { |
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306 | handlePtrType( at ); |
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307 | } |
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308 | |
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309 | void Resolver::previsit( PointerType * pt ) { |
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310 | handlePtrType( pt ); |
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311 | } |
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312 | |
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313 | void Resolver::previsit( TypeDecl *typeDecl ) { |
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314 | if ( typeDecl->get_base() ) { |
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315 | Type *new_type = resolveTypeof( typeDecl->get_base(), indexer ); |
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316 | typeDecl->set_base( new_type ); |
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317 | } // if |
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318 | } |
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319 | |
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320 | void Resolver::previsit( FunctionDecl *functionDecl ) { |
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321 | #if 0 |
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322 | std::cerr << "resolver visiting functiondecl "; |
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323 | functionDecl->print( std::cerr ); |
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324 | std::cerr << std::endl; |
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325 | #endif |
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326 | Type *new_type = resolveTypeof( functionDecl->type, indexer ); |
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327 | functionDecl->set_type( new_type ); |
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328 | GuardValue( functionReturn ); |
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329 | functionReturn = ResolvExpr::extractResultType( functionDecl->type ); |
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330 | |
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331 | { |
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332 | // resolve with-exprs with parameters in scope and add any newly generated declarations to the |
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333 | // front of the function body. |
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334 | auto guard = makeFuncGuard( [this]() { indexer.enterScope(); }, [this](){ indexer.leaveScope(); } ); |
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335 | indexer.addFunctionType( functionDecl->type ); |
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336 | std::list< Statement * > newStmts; |
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337 | resolveWithExprs( functionDecl->withExprs, newStmts ); |
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338 | if ( functionDecl->statements ) { |
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339 | functionDecl->statements->kids.splice( functionDecl->statements->kids.begin(), newStmts ); |
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340 | } else { |
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341 | assertf( functionDecl->withExprs.empty() && newStmts.empty(), "Function %s without a body has with-clause and/or generated with declarations.", functionDecl->name.c_str() ); |
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342 | } |
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343 | } |
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344 | } |
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345 | |
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346 | void Resolver::postvisit( FunctionDecl *functionDecl ) { |
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347 | // default value expressions have an environment which shouldn't be there and trips up later passes. |
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348 | // xxx - it might be necessary to somehow keep the information from this environment, but I can't currently |
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349 | // see how it's useful. |
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350 | for ( Declaration * d : functionDecl->type->parameters ) { |
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351 | if ( ObjectDecl * obj = dynamic_cast< ObjectDecl * >( d ) ) { |
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352 | if ( SingleInit * init = dynamic_cast< SingleInit * >( obj->init ) ) { |
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353 | delete init->value->env; |
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354 | init->value->env = nullptr; |
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355 | } |
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356 | } |
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357 | } |
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358 | } |
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359 | |
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360 | void Resolver::previsit( EnumDecl * ) { |
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361 | // in case we decide to allow nested enums |
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362 | GuardValue( inEnumDecl ); |
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363 | inEnumDecl = true; |
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364 | } |
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365 | |
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366 | void Resolver::previsit( StaticAssertDecl * assertDecl ) { |
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367 | findIntegralExpression( assertDecl->condition, indexer ); |
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368 | } |
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369 | |
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370 | void Resolver::previsit( ExprStmt *exprStmt ) { |
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371 | visit_children = false; |
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372 | assertf( exprStmt->expr, "ExprStmt has null Expression in resolver" ); |
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373 | findVoidExpression( exprStmt->expr, indexer ); |
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374 | } |
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375 | |
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376 | void Resolver::previsit( AsmExpr *asmExpr ) { |
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377 | visit_children = false; |
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378 | findVoidExpression( asmExpr->operand, indexer ); |
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379 | if ( asmExpr->get_inout() ) { |
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380 | findVoidExpression( asmExpr->inout, indexer ); |
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381 | } // if |
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382 | } |
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383 | |
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384 | void Resolver::previsit( AsmStmt *asmStmt ) { |
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385 | visit_children = false; |
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386 | acceptAll( asmStmt->get_input(), *visitor ); |
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387 | acceptAll( asmStmt->get_output(), *visitor ); |
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388 | } |
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389 | |
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390 | void Resolver::previsit( IfStmt *ifStmt ) { |
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391 | findIntegralExpression( ifStmt->condition, indexer ); |
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392 | } |
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393 | |
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394 | void Resolver::previsit( WhileStmt *whileStmt ) { |
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395 | findIntegralExpression( whileStmt->condition, indexer ); |
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396 | } |
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397 | |
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398 | void Resolver::previsit( ForStmt *forStmt ) { |
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399 | if ( forStmt->condition ) { |
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400 | findIntegralExpression( forStmt->condition, indexer ); |
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401 | } // if |
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402 | |
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403 | if ( forStmt->increment ) { |
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404 | findVoidExpression( forStmt->increment, indexer ); |
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405 | } // if |
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406 | } |
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407 | |
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408 | void Resolver::previsit( SwitchStmt *switchStmt ) { |
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409 | GuardValue( currentObject ); |
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410 | findIntegralExpression( switchStmt->condition, indexer ); |
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411 | |
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412 | currentObject = CurrentObject( switchStmt->condition->result ); |
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413 | } |
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414 | |
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415 | void Resolver::previsit( CaseStmt *caseStmt ) { |
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416 | if ( caseStmt->get_condition() ) { |
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417 | std::list< InitAlternative > initAlts = currentObject.getOptions(); |
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418 | assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral expression." ); |
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419 | // must remove cast from case statement because RangeExpr cannot be cast. |
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420 | Expression * newExpr = new CastExpr( caseStmt->condition, initAlts.front().type->clone() ); |
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421 | findSingleExpression( newExpr, indexer ); |
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422 | CastExpr * castExpr = strict_dynamic_cast< CastExpr * >( newExpr ); |
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423 | caseStmt->condition = castExpr->arg; |
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424 | castExpr->arg = nullptr; |
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425 | delete castExpr; |
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426 | } |
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427 | } |
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428 | |
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429 | void Resolver::previsit( BranchStmt *branchStmt ) { |
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430 | visit_children = false; |
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431 | // must resolve the argument for a computed goto |
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432 | if ( branchStmt->get_type() == BranchStmt::Goto ) { // check for computed goto statement |
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433 | if ( branchStmt->computedTarget ) { |
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434 | // computed goto argument is void * |
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435 | findSingleExpression( branchStmt->computedTarget, new PointerType( Type::Qualifiers(), new VoidType( Type::Qualifiers() ) ), indexer ); |
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436 | } // if |
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437 | } // if |
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438 | } |
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439 | |
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440 | void Resolver::previsit( ReturnStmt *returnStmt ) { |
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441 | visit_children = false; |
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442 | if ( returnStmt->expr ) { |
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443 | findSingleExpression( returnStmt->expr, functionReturn->clone(), indexer ); |
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444 | } // if |
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445 | } |
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446 | |
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447 | void Resolver::previsit( ThrowStmt *throwStmt ) { |
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448 | visit_children = false; |
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449 | // TODO: Replace *exception type with &exception type. |
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450 | if ( throwStmt->get_expr() ) { |
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451 | StructDecl * exception_decl = |
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452 | indexer.lookupStruct( "__cfaabi_ehm__base_exception_t" ); |
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453 | assert( exception_decl ); |
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454 | Type * exceptType = new PointerType( noQualifiers, new StructInstType( noQualifiers, exception_decl ) ); |
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455 | findSingleExpression( throwStmt->expr, exceptType, indexer ); |
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456 | } |
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457 | } |
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458 | |
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459 | void Resolver::previsit( CatchStmt *catchStmt ) { |
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460 | if ( catchStmt->cond ) { |
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461 | findSingleExpression( catchStmt->cond, new BasicType( noQualifiers, BasicType::Bool ), indexer ); |
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462 | } |
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463 | } |
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464 | |
---|
465 | template< typename iterator_t > |
---|
466 | inline bool advance_to_mutex( iterator_t & it, const iterator_t & end ) { |
---|
467 | while( it != end && !(*it)->get_type()->get_mutex() ) { |
---|
468 | it++; |
---|
469 | } |
---|
470 | |
---|
471 | return it != end; |
---|
472 | } |
---|
473 | |
---|
474 | void Resolver::previsit( WaitForStmt * stmt ) { |
---|
475 | visit_children = false; |
---|
476 | |
---|
477 | // Resolve all clauses first |
---|
478 | for( auto& clause : stmt->clauses ) { |
---|
479 | |
---|
480 | TypeEnvironment env; |
---|
481 | AlternativeFinder funcFinder( indexer, env ); |
---|
482 | |
---|
483 | // Find all alternatives for a function in canonical form |
---|
484 | funcFinder.findWithAdjustment( clause.target.function ); |
---|
485 | |
---|
486 | if ( funcFinder.get_alternatives().empty() ) { |
---|
487 | stringstream ss; |
---|
488 | ss << "Use of undeclared indentifier '"; |
---|
489 | ss << strict_dynamic_cast<NameExpr*>( clause.target.function )->name; |
---|
490 | ss << "' in call to waitfor"; |
---|
491 | SemanticError( stmt->location, ss.str() ); |
---|
492 | } |
---|
493 | |
---|
494 | if(clause.target.arguments.empty()) { |
---|
495 | SemanticError( stmt->location, "Waitfor clause must have at least one mutex parameter"); |
---|
496 | } |
---|
497 | |
---|
498 | // Find all alternatives for all arguments in canonical form |
---|
499 | std::vector< AlternativeFinder > argAlternatives; |
---|
500 | funcFinder.findSubExprs( clause.target.arguments.begin(), clause.target.arguments.end(), back_inserter( argAlternatives ) ); |
---|
501 | |
---|
502 | // List all combinations of arguments |
---|
503 | std::vector< AltList > possibilities; |
---|
504 | combos( argAlternatives.begin(), argAlternatives.end(), back_inserter( possibilities ) ); |
---|
505 | |
---|
506 | AltList func_candidates; |
---|
507 | std::vector< AltList > args_candidates; |
---|
508 | |
---|
509 | // For every possible function : |
---|
510 | // try matching the arguments to the parameters |
---|
511 | // not the other way around because we have more arguments than parameters |
---|
512 | SemanticErrorException errors; |
---|
513 | for ( Alternative & func : funcFinder.get_alternatives() ) { |
---|
514 | try { |
---|
515 | PointerType * pointer = dynamic_cast< PointerType* >( func.expr->get_result()->stripReferences() ); |
---|
516 | if( !pointer ) { |
---|
517 | SemanticError( func.expr->get_result(), "candidate not viable: not a pointer type\n" ); |
---|
518 | } |
---|
519 | |
---|
520 | FunctionType * function = dynamic_cast< FunctionType* >( pointer->get_base() ); |
---|
521 | if( !function ) { |
---|
522 | SemanticError( pointer->get_base(), "candidate not viable: not a function type\n" ); |
---|
523 | } |
---|
524 | |
---|
525 | |
---|
526 | { |
---|
527 | auto param = function->parameters.begin(); |
---|
528 | auto param_end = function->parameters.end(); |
---|
529 | |
---|
530 | if( !advance_to_mutex( param, param_end ) ) { |
---|
531 | SemanticError(function, "candidate function not viable: no mutex parameters\n"); |
---|
532 | } |
---|
533 | } |
---|
534 | |
---|
535 | Alternative newFunc( func ); |
---|
536 | // Strip reference from function |
---|
537 | referenceToRvalueConversion( newFunc.expr, newFunc.cost ); |
---|
538 | |
---|
539 | // For all the set of arguments we have try to match it with the parameter of the current function alternative |
---|
540 | for ( auto & argsList : possibilities ) { |
---|
541 | |
---|
542 | try { |
---|
543 | // Declare data structures need for resolution |
---|
544 | OpenVarSet openVars; |
---|
545 | AssertionSet resultNeed, resultHave; |
---|
546 | TypeEnvironment resultEnv( func.env ); |
---|
547 | makeUnifiableVars( function, openVars, resultNeed ); |
---|
548 | // add all type variables as open variables now so that those not used in the parameter |
---|
549 | // list are still considered open. |
---|
550 | resultEnv.add( function->forall ); |
---|
551 | |
---|
552 | // Load type variables from arguemnts into one shared space |
---|
553 | simpleCombineEnvironments( argsList.begin(), argsList.end(), resultEnv ); |
---|
554 | |
---|
555 | // Make sure we don't widen any existing bindings |
---|
556 | for ( auto & i : resultEnv ) { |
---|
557 | i.allowWidening = false; |
---|
558 | } |
---|
559 | |
---|
560 | // Find any unbound type variables |
---|
561 | resultEnv.extractOpenVars( openVars ); |
---|
562 | |
---|
563 | auto param = function->parameters.begin(); |
---|
564 | auto param_end = function->parameters.end(); |
---|
565 | |
---|
566 | int n_mutex_arg = 0; |
---|
567 | |
---|
568 | // For every arguments of its set, check if it matches one of the parameter |
---|
569 | // The order is important |
---|
570 | for( auto & arg : argsList ) { |
---|
571 | |
---|
572 | // Ignore non-mutex arguments |
---|
573 | if( !advance_to_mutex( param, param_end ) ) { |
---|
574 | // We ran out of parameters but still have arguments |
---|
575 | // this function doesn't match |
---|
576 | SemanticError( function, toString("candidate function not viable: too many mutex arguments, expected ", n_mutex_arg, "\n" )); |
---|
577 | } |
---|
578 | |
---|
579 | n_mutex_arg++; |
---|
580 | |
---|
581 | // Check if the argument matches the parameter type in the current scope |
---|
582 | if( ! unify( arg.expr->get_result(), (*param)->get_type(), resultEnv, resultNeed, resultHave, openVars, this->indexer ) ) { |
---|
583 | // Type doesn't match |
---|
584 | stringstream ss; |
---|
585 | ss << "candidate function not viable: no known convertion from '"; |
---|
586 | (*param)->get_type()->print( ss ); |
---|
587 | ss << "' to '"; |
---|
588 | arg.expr->get_result()->print( ss ); |
---|
589 | ss << "' with env '"; |
---|
590 | resultEnv.print(ss); |
---|
591 | ss << "'\n"; |
---|
592 | SemanticError( function, ss.str() ); |
---|
593 | } |
---|
594 | |
---|
595 | param++; |
---|
596 | } |
---|
597 | |
---|
598 | // All arguments match ! |
---|
599 | |
---|
600 | // Check if parameters are missing |
---|
601 | if( advance_to_mutex( param, param_end ) ) { |
---|
602 | // We ran out of arguments but still have parameters left |
---|
603 | // this function doesn't match |
---|
604 | SemanticError( function, toString("candidate function not viable: too few mutex arguments, expected ", n_mutex_arg, "\n" )); |
---|
605 | } |
---|
606 | |
---|
607 | // All parameters match ! |
---|
608 | |
---|
609 | // Finish the expressions to tie in the proper environments |
---|
610 | finishExpr( newFunc.expr, resultEnv ); |
---|
611 | for( Alternative & alt : argsList ) { |
---|
612 | finishExpr( alt.expr, resultEnv ); |
---|
613 | } |
---|
614 | |
---|
615 | // This is a match store it and save it for later |
---|
616 | func_candidates.push_back( newFunc ); |
---|
617 | args_candidates.push_back( argsList ); |
---|
618 | |
---|
619 | } |
---|
620 | catch( SemanticErrorException &e ) { |
---|
621 | errors.append( e ); |
---|
622 | } |
---|
623 | } |
---|
624 | } |
---|
625 | catch( SemanticErrorException &e ) { |
---|
626 | errors.append( e ); |
---|
627 | } |
---|
628 | } |
---|
629 | |
---|
630 | // Make sure we got the right number of arguments |
---|
631 | if( func_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for function in call to waitfor" ); top.append( errors ); throw top; } |
---|
632 | if( args_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for arguments in call to waitfor" ); top.append( errors ); throw top; } |
---|
633 | if( func_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous function in call to waitfor" ); top.append( errors ); throw top; } |
---|
634 | if( args_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous arguments in call to waitfor" ); top.append( errors ); throw top; } |
---|
635 | // TODO: need to use findDeletedExpr to ensure no deleted identifiers are used. |
---|
636 | |
---|
637 | // Swap the results from the alternative with the unresolved values. |
---|
638 | // Alternatives will handle deletion on destruction |
---|
639 | std::swap( clause.target.function, func_candidates.front().expr ); |
---|
640 | for( auto arg_pair : group_iterate( clause.target.arguments, args_candidates.front() ) ) { |
---|
641 | std::swap ( std::get<0>( arg_pair), std::get<1>( arg_pair).expr ); |
---|
642 | } |
---|
643 | |
---|
644 | // Resolve the conditions as if it were an IfStmt |
---|
645 | // Resolve the statments normally |
---|
646 | findSingleExpression( clause.condition, this->indexer ); |
---|
647 | clause.statement->accept( *visitor ); |
---|
648 | } |
---|
649 | |
---|
650 | |
---|
651 | if( stmt->timeout.statement ) { |
---|
652 | // Resolve the timeout as an size_t for now |
---|
653 | // Resolve the conditions as if it were an IfStmt |
---|
654 | // Resolve the statments normally |
---|
655 | findSingleExpression( stmt->timeout.time, new BasicType( noQualifiers, BasicType::LongLongUnsignedInt ), this->indexer ); |
---|
656 | findSingleExpression( stmt->timeout.condition, this->indexer ); |
---|
657 | stmt->timeout.statement->accept( *visitor ); |
---|
658 | } |
---|
659 | |
---|
660 | if( stmt->orelse.statement ) { |
---|
661 | // Resolve the conditions as if it were an IfStmt |
---|
662 | // Resolve the statments normally |
---|
663 | findSingleExpression( stmt->orelse.condition, this->indexer ); |
---|
664 | stmt->orelse.statement->accept( *visitor ); |
---|
665 | } |
---|
666 | } |
---|
667 | |
---|
668 | bool isStructOrUnion( const Alternative & alt ) { |
---|
669 | Type * t = alt.expr->result->stripReferences(); |
---|
670 | return dynamic_cast< StructInstType * >( t ) || dynamic_cast< UnionInstType * >( t ); |
---|
671 | } |
---|
672 | |
---|
673 | void Resolver::resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts ) { |
---|
674 | for ( Expression *& expr : withExprs ) { |
---|
675 | // only struct- and union-typed expressions are viable candidates |
---|
676 | findKindExpression( expr, indexer, "with statement", isStructOrUnion ); |
---|
677 | |
---|
678 | // if with expression might be impure, create a temporary so that it is evaluated once |
---|
679 | if ( Tuples::maybeImpure( expr ) ) { |
---|
680 | static UniqueName tmpNamer( "_with_tmp_" ); |
---|
681 | ObjectDecl * tmp = ObjectDecl::newObject( tmpNamer.newName(), expr->result->clone(), new SingleInit( expr ) ); |
---|
682 | expr = new VariableExpr( tmp ); |
---|
683 | newStmts.push_back( new DeclStmt( tmp ) ); |
---|
684 | if ( InitTweak::isConstructable( tmp->type ) ) { |
---|
685 | // generate ctor/dtor and resolve them |
---|
686 | tmp->init = InitTweak::genCtorInit( tmp ); |
---|
687 | tmp->accept( *visitor ); |
---|
688 | } |
---|
689 | } |
---|
690 | } |
---|
691 | } |
---|
692 | |
---|
693 | void Resolver::previsit( WithStmt * withStmt ) { |
---|
694 | resolveWithExprs( withStmt->exprs, stmtsToAddBefore ); |
---|
695 | } |
---|
696 | |
---|
697 | template< typename T > |
---|
698 | bool isCharType( T t ) { |
---|
699 | if ( BasicType * bt = dynamic_cast< BasicType * >( t ) ) { |
---|
700 | return bt->get_kind() == BasicType::Char || bt->get_kind() == BasicType::SignedChar || |
---|
701 | bt->get_kind() == BasicType::UnsignedChar; |
---|
702 | } |
---|
703 | return false; |
---|
704 | } |
---|
705 | |
---|
706 | void Resolver::previsit( SingleInit *singleInit ) { |
---|
707 | visit_children = false; |
---|
708 | // resolve initialization using the possibilities as determined by the currentObject cursor |
---|
709 | Expression * newExpr = new UntypedInitExpr( singleInit->value, currentObject.getOptions() ); |
---|
710 | findSingleExpression( newExpr, indexer ); |
---|
711 | InitExpr * initExpr = strict_dynamic_cast< InitExpr * >( newExpr ); |
---|
712 | |
---|
713 | // move cursor to the object that is actually initialized |
---|
714 | currentObject.setNext( initExpr->get_designation() ); |
---|
715 | |
---|
716 | // discard InitExpr wrapper and retain relevant pieces |
---|
717 | newExpr = initExpr->expr; |
---|
718 | initExpr->expr = nullptr; |
---|
719 | std::swap( initExpr->env, newExpr->env ); |
---|
720 | std::swap( initExpr->inferParams, newExpr->inferParams ) ; |
---|
721 | delete initExpr; |
---|
722 | |
---|
723 | // get the actual object's type (may not exactly match what comes back from the resolver due to conversions) |
---|
724 | Type * initContext = currentObject.getCurrentType(); |
---|
725 | |
---|
726 | removeExtraneousCast( newExpr, indexer ); |
---|
727 | |
---|
728 | // check if actual object's type is char[] |
---|
729 | if ( ArrayType * at = dynamic_cast< ArrayType * >( initContext ) ) { |
---|
730 | if ( isCharType( at->get_base() ) ) { |
---|
731 | // check if the resolved type is char * |
---|
732 | if ( PointerType * pt = dynamic_cast< PointerType *>( newExpr->get_result() ) ) { |
---|
733 | if ( isCharType( pt->get_base() ) ) { |
---|
734 | if ( CastExpr *ce = dynamic_cast< CastExpr * >( newExpr ) ) { |
---|
735 | // strip cast if we're initializing a char[] with a char *, e.g. char x[] = "hello"; |
---|
736 | newExpr = ce->get_arg(); |
---|
737 | ce->set_arg( nullptr ); |
---|
738 | std::swap( ce->env, newExpr->env ); |
---|
739 | delete ce; |
---|
740 | } |
---|
741 | } |
---|
742 | } |
---|
743 | } |
---|
744 | } |
---|
745 | |
---|
746 | // set initializer expr to resolved express |
---|
747 | singleInit->value = newExpr; |
---|
748 | |
---|
749 | // move cursor to next object in preparation for next initializer |
---|
750 | currentObject.increment(); |
---|
751 | } |
---|
752 | |
---|
753 | void Resolver::previsit( ListInit * listInit ) { |
---|
754 | visit_children = false; |
---|
755 | // move cursor into brace-enclosed initializer-list |
---|
756 | currentObject.enterListInit(); |
---|
757 | // xxx - fix this so that the list isn't copied, iterator should be used to change current element |
---|
758 | std::list<Designation *> newDesignations; |
---|
759 | for ( auto p : group_iterate(listInit->get_designations(), listInit->get_initializers()) ) { |
---|
760 | // iterate designations and initializers in pairs, moving the cursor to the current designated object and resolving |
---|
761 | // the initializer against that object. |
---|
762 | Designation * des = std::get<0>(p); |
---|
763 | Initializer * init = std::get<1>(p); |
---|
764 | newDesignations.push_back( currentObject.findNext( des ) ); |
---|
765 | init->accept( *visitor ); |
---|
766 | } |
---|
767 | // set the set of 'resolved' designations and leave the brace-enclosed initializer-list |
---|
768 | listInit->get_designations() = newDesignations; // xxx - memory management |
---|
769 | currentObject.exitListInit(); |
---|
770 | |
---|
771 | // xxx - this part has not be folded into CurrentObject yet |
---|
772 | // } else if ( TypeInstType * tt = dynamic_cast< TypeInstType * >( initContext ) ) { |
---|
773 | // Type * base = tt->get_baseType()->get_base(); |
---|
774 | // if ( base ) { |
---|
775 | // // know the implementation type, so try using that as the initContext |
---|
776 | // ObjectDecl tmpObj( "", Type::StorageClasses(), LinkageSpec::Cforall, nullptr, base->clone(), nullptr ); |
---|
777 | // currentObject = &tmpObj; |
---|
778 | // visit( listInit ); |
---|
779 | // } else { |
---|
780 | // // missing implementation type -- might be an unknown type variable, so try proceeding with the current init context |
---|
781 | // Parent::visit( listInit ); |
---|
782 | // } |
---|
783 | // } else { |
---|
784 | } |
---|
785 | |
---|
786 | // ConstructorInit - fall back on C-style initializer |
---|
787 | void Resolver::fallbackInit( ConstructorInit * ctorInit ) { |
---|
788 | // could not find valid constructor, or found an intrinsic constructor |
---|
789 | // fall back on C-style initializer |
---|
790 | delete ctorInit->get_ctor(); |
---|
791 | ctorInit->set_ctor( NULL ); |
---|
792 | delete ctorInit->get_dtor(); |
---|
793 | ctorInit->set_dtor( NULL ); |
---|
794 | maybeAccept( ctorInit->get_init(), *visitor ); |
---|
795 | } |
---|
796 | |
---|
797 | // needs to be callable from outside the resolver, so this is a standalone function |
---|
798 | void resolveCtorInit( ConstructorInit * ctorInit, const SymTab::Indexer & indexer ) { |
---|
799 | assert( ctorInit ); |
---|
800 | PassVisitor<Resolver> resolver( indexer ); |
---|
801 | ctorInit->accept( resolver ); |
---|
802 | } |
---|
803 | |
---|
804 | void resolveStmtExpr( StmtExpr * stmtExpr, const SymTab::Indexer & indexer ) { |
---|
805 | assert( stmtExpr ); |
---|
806 | PassVisitor<Resolver> resolver( indexer ); |
---|
807 | stmtExpr->accept( resolver ); |
---|
808 | stmtExpr->computeResult(); |
---|
809 | // xxx - aggregate the environments from all statements? Possibly in AlternativeFinder instead? |
---|
810 | } |
---|
811 | |
---|
812 | void Resolver::previsit( ConstructorInit *ctorInit ) { |
---|
813 | visit_children = false; |
---|
814 | // xxx - fallback init has been removed => remove fallbackInit function and remove complexity from FixInit and remove C-init from ConstructorInit |
---|
815 | maybeAccept( ctorInit->ctor, *visitor ); |
---|
816 | maybeAccept( ctorInit->dtor, *visitor ); |
---|
817 | |
---|
818 | // found a constructor - can get rid of C-style initializer |
---|
819 | delete ctorInit->init; |
---|
820 | ctorInit->init = nullptr; |
---|
821 | |
---|
822 | // intrinsic single parameter constructors and destructors do nothing. Since this was |
---|
823 | // implicitly generated, there's no way for it to have side effects, so get rid of it |
---|
824 | // to clean up generated code. |
---|
825 | if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->ctor ) ) { |
---|
826 | delete ctorInit->ctor; |
---|
827 | ctorInit->ctor = nullptr; |
---|
828 | } |
---|
829 | |
---|
830 | if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->dtor ) ) { |
---|
831 | delete ctorInit->dtor; |
---|
832 | ctorInit->dtor = nullptr; |
---|
833 | } |
---|
834 | |
---|
835 | // xxx - todo -- what about arrays? |
---|
836 | // if ( dtor == NULL && InitTweak::isIntrinsicCallStmt( ctorInit->get_ctor() ) ) { |
---|
837 | // // can reduce the constructor down to a SingleInit using the |
---|
838 | // // second argument from the ctor call, since |
---|
839 | // delete ctorInit->get_ctor(); |
---|
840 | // ctorInit->set_ctor( NULL ); |
---|
841 | |
---|
842 | // Expression * arg = |
---|
843 | // ctorInit->set_init( new SingleInit( arg ) ); |
---|
844 | // } |
---|
845 | } |
---|
846 | } // namespace ResolvExpr |
---|
847 | |
---|
848 | // Local Variables: // |
---|
849 | // tab-width: 4 // |
---|
850 | // mode: c++ // |
---|
851 | // compile-command: "make install" // |
---|
852 | // End: // |
---|