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 | // Unify.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 12:27:10 2015 |
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11 | // Last Modified By : Aaron B. Moss |
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12 | // Last Modified On : Mon Jun 18 11:58:00 2018 |
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13 | // Update Count : 43 |
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14 | // |
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15 | |
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16 | #include <cassert> // for assertf, assert |
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17 | #include <iterator> // for back_insert_iterator, back_inserter |
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18 | #include <map> // for _Rb_tree_const_iterator, _Rb_tree_i... |
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19 | #include <set> // for set |
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20 | #include <string> // for string, operator==, operator!=, bas... |
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21 | #include <utility> // for pair, move |
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22 | |
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23 | #include "Common/PassVisitor.h" // for PassVisitor |
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24 | #include "FindOpenVars.h" // for findOpenVars |
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25 | #include "Parser/LinkageSpec.h" // for C |
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26 | #include "SynTree/Constant.h" // for Constant |
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27 | #include "SynTree/Declaration.h" // for TypeDecl, TypeDecl::Data, Declarati... |
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28 | #include "SynTree/Expression.h" // for TypeExpr, Expression, ConstantExpr |
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29 | #include "SynTree/Mutator.h" // for Mutator |
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30 | #include "SynTree/Type.h" // for Type, TypeInstType, FunctionType |
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31 | #include "SynTree/Visitor.h" // for Visitor |
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32 | #include "Tuples/Tuples.h" // for isTtype |
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33 | #include "TypeEnvironment.h" // for EqvClass, AssertionSet, OpenVarSet |
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34 | #include "Unify.h" |
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35 | #include "typeops.h" // for flatten, occurs, commonType |
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36 | |
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37 | namespace SymTab { |
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38 | class Indexer; |
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39 | } // namespace SymTab |
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40 | |
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41 | // #define DEBUG |
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42 | |
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43 | namespace ResolvExpr { |
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44 | |
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45 | struct Unify : public WithShortCircuiting { |
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46 | Unify( Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer ); |
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47 | |
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48 | bool get_result() const { return result; } |
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49 | |
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50 | void previsit( BaseSyntaxNode * ) { visit_children = false; } |
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51 | |
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52 | void postvisit( VoidType * voidType ); |
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53 | void postvisit( BasicType * basicType ); |
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54 | void postvisit( PointerType * pointerType ); |
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55 | void postvisit( ArrayType * arrayType ); |
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56 | void postvisit( ReferenceType * refType ); |
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57 | void postvisit( FunctionType * functionType ); |
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58 | void postvisit( StructInstType * aggregateUseType ); |
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59 | void postvisit( UnionInstType * aggregateUseType ); |
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60 | void postvisit( EnumInstType * aggregateUseType ); |
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61 | void postvisit( TraitInstType * aggregateUseType ); |
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62 | void postvisit( TypeInstType * aggregateUseType ); |
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63 | void postvisit( TupleType * tupleType ); |
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64 | void postvisit( VarArgsType * varArgsType ); |
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65 | void postvisit( ZeroType * zeroType ); |
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66 | void postvisit( OneType * oneType ); |
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67 | |
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68 | private: |
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69 | template< typename RefType > void handleRefType( RefType *inst, Type *other ); |
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70 | template< typename RefType > void handleGenericRefType( RefType *inst, Type *other ); |
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71 | |
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72 | bool result; |
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73 | Type *type2; // inherited |
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74 | TypeEnvironment &env; |
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75 | AssertionSet &needAssertions; |
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76 | AssertionSet &haveAssertions; |
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77 | const OpenVarSet &openVars; |
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78 | WidenMode widenMode; |
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79 | const SymTab::Indexer &indexer; |
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80 | }; |
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81 | |
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82 | /// Attempts an inexact unification of type1 and type2. |
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83 | /// Returns false if no such unification; if the types can be unified, sets common (unless they unify exactly and have identical type qualifiers) |
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84 | bool unifyInexact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer, Type *&common ); |
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85 | bool unifyExact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer ); |
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86 | |
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87 | bool typesCompatible( Type *first, Type *second, const SymTab::Indexer &indexer, const TypeEnvironment &env ) { |
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88 | TypeEnvironment newEnv; |
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89 | OpenVarSet openVars, closedVars; // added closedVars |
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90 | AssertionSet needAssertions, haveAssertions; |
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91 | Type *newFirst = first->clone(), *newSecond = second->clone(); |
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92 | env.apply( newFirst ); |
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93 | env.apply( newSecond ); |
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94 | |
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95 | // do we need to do this? Seems like we do, types should be able to be compatible if they |
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96 | // have free variables that can unify |
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97 | findOpenVars( newFirst, openVars, closedVars, needAssertions, haveAssertions, false ); |
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98 | findOpenVars( newSecond, openVars, closedVars, needAssertions, haveAssertions, true ); |
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99 | |
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100 | return unifyExact( newFirst, newSecond, newEnv, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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101 | } |
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102 | |
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103 | bool typesCompatibleIgnoreQualifiers( Type *first, Type *second, const SymTab::Indexer &indexer, const TypeEnvironment &env ) { |
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104 | TypeEnvironment newEnv; |
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105 | OpenVarSet openVars; |
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106 | AssertionSet needAssertions, haveAssertions; |
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107 | Type *newFirst = first->clone(), *newSecond = second->clone(); |
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108 | env.apply( newFirst ); |
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109 | env.apply( newSecond ); |
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110 | newFirst->get_qualifiers() = Type::Qualifiers(); |
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111 | newSecond->get_qualifiers() = Type::Qualifiers(); |
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112 | /// std::cerr << "first is "; |
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113 | /// first->print( std::cerr ); |
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114 | /// std::cerr << std::endl << "second is "; |
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115 | /// second->print( std::cerr ); |
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116 | /// std::cerr << std::endl << "newFirst is "; |
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117 | /// newFirst->print( std::cerr ); |
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118 | /// std::cerr << std::endl << "newSecond is "; |
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119 | /// newSecond->print( std::cerr ); |
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120 | /// std::cerr << std::endl; |
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121 | return unifyExact( newFirst, newSecond, newEnv, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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122 | } |
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123 | |
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124 | bool unify( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, OpenVarSet &openVars, const SymTab::Indexer &indexer ) { |
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125 | OpenVarSet closedVars; |
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126 | findOpenVars( type1, openVars, closedVars, needAssertions, haveAssertions, false ); |
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127 | findOpenVars( type2, openVars, closedVars, needAssertions, haveAssertions, true ); |
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128 | Type *commonType = 0; |
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129 | return unifyInexact( type1, type2, env, needAssertions, haveAssertions, openVars, WidenMode( true, true ), indexer, commonType ); |
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130 | } |
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131 | |
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132 | bool unify( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, OpenVarSet &openVars, const SymTab::Indexer &indexer, Type *&commonType ) { |
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133 | OpenVarSet closedVars; |
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134 | findOpenVars( type1, openVars, closedVars, needAssertions, haveAssertions, false ); |
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135 | findOpenVars( type2, openVars, closedVars, needAssertions, haveAssertions, true ); |
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136 | return unifyInexact( type1, type2, env, needAssertions, haveAssertions, openVars, WidenMode( true, true ), indexer, commonType ); |
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137 | } |
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138 | |
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139 | bool unifyExact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer ) { |
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140 | #ifdef DEBUG |
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141 | TypeEnvironment debugEnv( env ); |
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142 | #endif |
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143 | if ( type1->get_qualifiers() != type2->get_qualifiers() ) { |
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144 | return false; |
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145 | } |
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146 | |
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147 | bool result; |
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148 | TypeInstType *var1 = dynamic_cast< TypeInstType* >( type1 ); |
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149 | TypeInstType *var2 = dynamic_cast< TypeInstType* >( type2 ); |
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150 | OpenVarSet::const_iterator entry1, entry2; |
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151 | if ( var1 ) { |
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152 | entry1 = openVars.find( var1->get_name() ); |
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153 | } // if |
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154 | if ( var2 ) { |
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155 | entry2 = openVars.find( var2->get_name() ); |
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156 | } // if |
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157 | bool isopen1 = var1 && ( entry1 != openVars.end() ); |
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158 | bool isopen2 = var2 && ( entry2 != openVars.end() ); |
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159 | |
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160 | if ( isopen1 && isopen2 && entry1->second == entry2->second ) { |
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161 | result = env.bindVarToVar( var1, var2, entry1->second, needAssertions, haveAssertions, openVars, widenMode, indexer ); |
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162 | } else if ( isopen1 ) { |
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163 | result = env.bindVar( var1, type2, entry1->second, needAssertions, haveAssertions, openVars, widenMode, indexer ); |
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164 | } else if ( isopen2 ) { // TODO: swap widenMode values in call, since type positions are flipped? |
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165 | result = env.bindVar( var2, type1, entry2->second, needAssertions, haveAssertions, openVars, widenMode, indexer ); |
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166 | } else { |
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167 | PassVisitor<Unify> comparator( type2, env, needAssertions, haveAssertions, openVars, widenMode, indexer ); |
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168 | type1->accept( comparator ); |
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169 | result = comparator.pass.get_result(); |
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170 | } // if |
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171 | #ifdef DEBUG |
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172 | std::cerr << "============ unifyExact" << std::endl; |
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173 | std::cerr << "type1 is "; |
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174 | type1->print( std::cerr ); |
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175 | std::cerr << std::endl << "type2 is "; |
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176 | type2->print( std::cerr ); |
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177 | std::cerr << std::endl << "openVars are "; |
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178 | printOpenVarSet( openVars, std::cerr, 8 ); |
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179 | std::cerr << std::endl << "input env is " << std::endl; |
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180 | debugEnv.print( std::cerr, 8 ); |
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181 | std::cerr << std::endl << "result env is " << std::endl; |
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182 | env.print( std::cerr, 8 ); |
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183 | std::cerr << "result is " << result << std::endl; |
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184 | #endif |
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185 | return result; |
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186 | } |
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187 | |
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188 | bool unifyExact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, OpenVarSet &openVars, const SymTab::Indexer &indexer ) { |
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189 | return unifyExact( type1, type2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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190 | } |
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191 | |
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192 | bool unifyInexact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer, Type *&common ) { |
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193 | Type::Qualifiers tq1 = type1->get_qualifiers(), tq2 = type2->get_qualifiers(); |
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194 | type1->get_qualifiers() = Type::Qualifiers(); |
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195 | type2->get_qualifiers() = Type::Qualifiers(); |
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196 | bool result; |
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197 | #ifdef DEBUG |
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198 | std::cerr << "unifyInexact type 1 is "; |
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199 | type1->print( std::cerr ); |
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200 | std::cerr << " type 2 is "; |
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201 | type2->print( std::cerr ); |
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202 | std::cerr << std::endl; |
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203 | #endif |
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204 | if ( ! unifyExact( type1, type2, env, needAssertions, haveAssertions, openVars, widenMode, indexer ) ) { |
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205 | #ifdef DEBUG |
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206 | std::cerr << "unifyInexact: no exact unification found" << std::endl; |
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207 | #endif |
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208 | if ( ( common = commonType( type1, type2, widenMode.widenFirst, widenMode.widenSecond, indexer, env, openVars ) ) ) { |
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209 | common->get_qualifiers() = tq1 | tq2; |
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210 | #ifdef DEBUG |
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211 | std::cerr << "unifyInexact: common type is "; |
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212 | common->print( std::cerr ); |
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213 | std::cerr << std::endl; |
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214 | #endif |
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215 | result = true; |
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216 | } else { |
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217 | #ifdef DEBUG |
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218 | std::cerr << "unifyInexact: no common type found" << std::endl; |
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219 | #endif |
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220 | result = false; |
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221 | } // if |
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222 | } else { |
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223 | if ( tq1 != tq2 ) { |
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224 | if ( ( tq1 > tq2 || widenMode.widenFirst ) && ( tq2 > tq1 || widenMode.widenSecond ) ) { |
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225 | common = type1->clone(); |
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226 | common->get_qualifiers() = tq1 | tq2; |
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227 | result = true; |
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228 | } else { |
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229 | result = false; |
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230 | } // if |
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231 | } else { |
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232 | common = type1->clone(); |
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233 | common->get_qualifiers() = tq1 | tq2; |
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234 | result = true; |
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235 | } // if |
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236 | } // if |
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237 | type1->get_qualifiers() = tq1; |
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238 | type2->get_qualifiers() = tq2; |
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239 | return result; |
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240 | } |
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241 | |
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242 | Unify::Unify( Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer ) |
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243 | : result( false ), type2( type2 ), env( env ), needAssertions( needAssertions ), haveAssertions( haveAssertions ), openVars( openVars ), widenMode( widenMode ), indexer( indexer ) { |
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244 | } |
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245 | |
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246 | void Unify::postvisit( __attribute__((unused)) VoidType *voidType) { |
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247 | result = dynamic_cast< VoidType* >( type2 ); |
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248 | } |
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249 | |
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250 | void Unify::postvisit(BasicType *basicType) { |
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251 | if ( BasicType *otherBasic = dynamic_cast< BasicType* >( type2 ) ) { |
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252 | result = basicType->get_kind() == otherBasic->get_kind(); |
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253 | } // if |
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254 | } |
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255 | |
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256 | void markAssertionSet( AssertionSet &assertions, DeclarationWithType *assert ) { |
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257 | /// std::cerr << "assertion set is" << std::endl; |
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258 | /// printAssertionSet( assertions, std::cerr, 8 ); |
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259 | /// std::cerr << "looking for "; |
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260 | /// assert->print( std::cerr ); |
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261 | /// std::cerr << std::endl; |
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262 | AssertionSet::iterator i = assertions.find( assert ); |
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263 | if ( i != assertions.end() ) { |
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264 | /// std::cerr << "found it!" << std::endl; |
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265 | i->second.isUsed = true; |
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266 | } // if |
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267 | } |
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268 | |
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269 | void markAssertions( AssertionSet &assertion1, AssertionSet &assertion2, Type *type ) { |
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270 | for ( std::list< TypeDecl* >::const_iterator tyvar = type->get_forall().begin(); tyvar != type->get_forall().end(); ++tyvar ) { |
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271 | for ( std::list< DeclarationWithType* >::const_iterator assert = (*tyvar)->get_assertions().begin(); assert != (*tyvar)->get_assertions().end(); ++assert ) { |
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272 | markAssertionSet( assertion1, *assert ); |
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273 | markAssertionSet( assertion2, *assert ); |
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274 | } // for |
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275 | } // for |
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276 | } |
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277 | |
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278 | void Unify::postvisit(PointerType *pointerType) { |
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279 | if ( PointerType *otherPointer = dynamic_cast< PointerType* >( type2 ) ) { |
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280 | result = unifyExact( pointerType->get_base(), otherPointer->get_base(), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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281 | markAssertions( haveAssertions, needAssertions, pointerType ); |
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282 | markAssertions( haveAssertions, needAssertions, otherPointer ); |
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283 | } // if |
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284 | } |
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285 | |
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286 | void Unify::postvisit(ReferenceType *refType) { |
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287 | if ( ReferenceType *otherRef = dynamic_cast< ReferenceType* >( type2 ) ) { |
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288 | result = unifyExact( refType->get_base(), otherRef->get_base(), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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289 | markAssertions( haveAssertions, needAssertions, refType ); |
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290 | markAssertions( haveAssertions, needAssertions, otherRef ); |
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291 | } // if |
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292 | } |
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293 | |
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294 | void Unify::postvisit(ArrayType *arrayType) { |
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295 | ArrayType *otherArray = dynamic_cast< ArrayType* >( type2 ); |
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296 | // to unify, array types must both be VLA or both not VLA |
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297 | // and must both have a dimension expression or not have a dimension |
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298 | if ( otherArray && arrayType->get_isVarLen() == otherArray->get_isVarLen() ) { |
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299 | |
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300 | if ( ! arrayType->get_isVarLen() && ! otherArray->get_isVarLen() && |
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301 | arrayType->get_dimension() != 0 && otherArray->get_dimension() != 0 ) { |
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302 | ConstantExpr * ce1 = dynamic_cast< ConstantExpr * >( arrayType->get_dimension() ); |
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303 | ConstantExpr * ce2 = dynamic_cast< ConstantExpr * >( otherArray->get_dimension() ); |
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304 | // see C11 Reference Manual 6.7.6.2.6 |
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305 | // two array types with size specifiers that are integer constant expressions are |
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306 | // compatible if both size specifiers have the same constant value |
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307 | if ( ce1 && ce2 ) { |
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308 | Constant * c1 = ce1->get_constant(); |
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309 | Constant * c2 = ce2->get_constant(); |
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310 | |
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311 | if ( c1->get_value() != c2->get_value() ) { |
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312 | // does not unify if the dimension is different |
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313 | return; |
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314 | } |
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315 | } |
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316 | } |
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317 | |
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318 | result = unifyExact( arrayType->get_base(), otherArray->get_base(), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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319 | } // if |
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320 | } |
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321 | |
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322 | template< typename Iterator, typename Func > |
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323 | Type* combineTypes( Iterator begin, Iterator end, Func & toType ) { |
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324 | std::list< Type * > types; |
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325 | for ( ; begin != end; ++begin ) { |
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326 | // it's guaranteed that a ttype variable will be bound to a flat tuple, so ensure that this results in a flat tuple |
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327 | flatten( toType( *begin ), back_inserter( types ) ); |
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328 | } |
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329 | return new TupleType{ Type::Qualifiers(), types }; |
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330 | } |
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331 | |
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332 | template< typename Iterator1, typename Iterator2 > |
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333 | bool unifyDeclList( Iterator1 list1Begin, Iterator1 list1End, Iterator2 list2Begin, Iterator2 list2End, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, const SymTab::Indexer &indexer ) { |
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334 | auto get_type = [](DeclarationWithType * dwt){ return dwt->get_type(); }; |
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335 | for ( ; list1Begin != list1End && list2Begin != list2End; ++list1Begin, ++list2Begin ) { |
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336 | Type * t1 = (*list1Begin)->get_type(); |
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337 | Type * t2 = (*list2Begin)->get_type(); |
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338 | bool isTtype1 = Tuples::isTtype( t1 ); |
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339 | bool isTtype2 = Tuples::isTtype( t2 ); |
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340 | // xxx - assumes ttype must be last parameter |
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341 | // xxx - there may be a nice way to refactor this, but be careful because the argument positioning might matter in some cases. |
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342 | if ( isTtype1 && ! isTtype2 ) { |
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343 | // combine all of the things in list2, then unify |
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344 | return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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345 | } else if ( isTtype2 && ! isTtype1 ) { |
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346 | // combine all of the things in list1, then unify |
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347 | return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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348 | } else if ( ! unifyExact( t1, t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ) ) { |
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349 | return false; |
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350 | } // if |
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351 | } // for |
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352 | // may get to the end of one argument list before the end of the other. This is only okay when the other is a ttype |
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353 | if ( list1Begin != list1End ) { |
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354 | // try unifying empty tuple type with ttype |
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355 | Type * t1 = (*list1Begin)->get_type(); |
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356 | if ( Tuples::isTtype( t1 ) ) { |
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357 | return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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358 | } else return false; |
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359 | } else if ( list2Begin != list2End ) { |
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360 | // try unifying empty tuple type with ttype |
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361 | Type * t2 = (*list2Begin)->get_type(); |
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362 | if ( Tuples::isTtype( t2 ) ) { |
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363 | return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
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364 | } else return false; |
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365 | } else { |
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366 | return true; |
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367 | } // if |
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368 | } |
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369 | |
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370 | /// Finds ttypes and replaces them with their expansion, if known. |
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371 | /// This needs to be done so that satisfying ttype assertions is easier. |
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372 | /// If this isn't done then argument lists can have wildly different |
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373 | /// size and structure, when they should be compatible. |
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374 | struct TtypeExpander : public WithShortCircuiting { |
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375 | TypeEnvironment & tenv; |
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376 | TtypeExpander( TypeEnvironment & tenv ) : tenv( tenv ) {} |
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377 | void premutate( TypeInstType * ) { visit_children = false; } |
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378 | Type * postmutate( TypeInstType * typeInst ) { |
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379 | if ( const EqvClass *eqvClass = tenv.lookup( typeInst->get_name() ) ) { |
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380 | // expand ttype parameter into its actual type |
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381 | if ( eqvClass->data.kind == TypeDecl::Ttype && eqvClass->type ) { |
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382 | return eqvClass->type->clone(); |
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383 | } |
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384 | } |
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385 | return typeInst; |
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386 | } |
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387 | }; |
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388 | |
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389 | /// flattens a list of declarations, so that each tuple type has a single declaration. |
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390 | /// makes use of TtypeExpander to ensure ttypes are flat as well. |
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391 | void flattenList( std::list< DeclarationWithType * > src, std::list< DeclarationWithType * > & dst, TypeEnvironment & env ) { |
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392 | dst.clear(); |
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393 | for ( DeclarationWithType * dcl : src ) { |
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394 | PassVisitor<TtypeExpander> expander( env ); |
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395 | dcl->acceptMutator( expander ); |
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396 | std::list< Type * > types; |
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397 | flatten( dcl->get_type(), back_inserter( types ) ); |
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398 | for ( Type * t : types ) { |
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399 | // outermost const, volatile, _Atomic qualifiers in parameters should not play a role in the unification of function types, since they do not determine whether a function is callable. |
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400 | // Note: MUST consider at least mutex qualifier, since functions can be overloaded on outermost mutex and a mutex function has different requirements than a non-mutex function. |
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401 | t->get_qualifiers() -= Type::Qualifiers(Type::Const | Type::Volatile | Type::Atomic); |
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402 | |
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403 | dst.push_back( new ObjectDecl( "", Type::StorageClasses(), LinkageSpec::C, nullptr, t, nullptr ) ); |
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404 | } |
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405 | } |
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406 | } |
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407 | |
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408 | void Unify::postvisit(FunctionType *functionType) { |
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409 | FunctionType *otherFunction = dynamic_cast< FunctionType* >( type2 ); |
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410 | if ( otherFunction && functionType->get_isVarArgs() == otherFunction->get_isVarArgs() ) { |
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411 | // flatten the parameter lists for both functions so that tuple structure |
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412 | // doesn't affect unification. Must be a clone so that the types don't change. |
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413 | FunctionType* flatFunc = functionType->clone(); |
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414 | FunctionType* flatOther = otherFunction->clone(); |
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415 | flattenList( flatFunc->get_parameters(), flatFunc->get_parameters(), env ); |
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416 | flattenList( flatOther->get_parameters(), flatOther->get_parameters(), env ); |
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417 | |
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418 | // sizes don't have to match if ttypes are involved; need to be more precise wrt where the ttype is to prevent errors |
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419 | if ( (flatFunc->parameters.size() == flatOther->parameters.size() && flatFunc->returnVals.size() == flatOther->returnVals.size()) || flatFunc->isTtype() || flatOther->isTtype() ) { |
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420 | if ( unifyDeclList( flatFunc->parameters.begin(), flatFunc->parameters.end(), flatOther->parameters.begin(), flatOther->parameters.end(), env, needAssertions, haveAssertions, openVars, indexer ) ) { |
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421 | if ( unifyDeclList( flatFunc->returnVals.begin(), flatFunc->returnVals.end(), flatOther->returnVals.begin(), flatOther->returnVals.end(), env, needAssertions, haveAssertions, openVars, indexer ) ) { |
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422 | |
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423 | // the original types must be used in mark assertions, since pointer comparisons are used |
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424 | markAssertions( haveAssertions, needAssertions, functionType ); |
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425 | markAssertions( haveAssertions, needAssertions, otherFunction ); |
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426 | |
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427 | result = true; |
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428 | } // if |
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429 | } // if |
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430 | } // if |
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431 | } // if |
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432 | } |
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433 | |
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434 | template< typename RefType > |
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435 | void Unify::handleRefType( RefType *inst, Type *other ) { |
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436 | // check that other type is compatible and named the same |
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437 | RefType *otherStruct = dynamic_cast< RefType* >( other ); |
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438 | result = otherStruct && inst->name == otherStruct->name; |
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439 | } |
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440 | |
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441 | template< typename RefType > |
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442 | void Unify::handleGenericRefType( RefType *inst, Type *other ) { |
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443 | // Check that other type is compatible and named the same |
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444 | handleRefType( inst, other ); |
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445 | if ( ! result ) return; |
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446 | // Check that parameters of types unify, if any |
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447 | std::list< Expression* > params = inst->parameters; |
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448 | std::list< Expression* > otherParams = ((RefType*)other)->parameters; |
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449 | |
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450 | std::list< Expression* >::const_iterator it = params.begin(), jt = otherParams.begin(); |
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451 | for ( ; it != params.end() && jt != otherParams.end(); ++it, ++jt ) { |
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452 | TypeExpr *param = dynamic_cast< TypeExpr* >(*it); |
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453 | assertf(param, "Aggregate parameters should be type expressions"); |
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454 | TypeExpr *otherParam = dynamic_cast< TypeExpr* >(*jt); |
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455 | assertf(otherParam, "Aggregate parameters should be type expressions"); |
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456 | |
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457 | Type* paramTy = param->get_type(); |
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458 | Type* otherParamTy = otherParam->get_type(); |
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459 | |
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460 | bool tupleParam = Tuples::isTtype( paramTy ); |
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461 | bool otherTupleParam = Tuples::isTtype( otherParamTy ); |
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462 | |
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463 | if ( tupleParam && otherTupleParam ) { |
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464 | ++it; ++jt; // skip ttype parameters for break |
---|
465 | } else if ( tupleParam ) { |
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466 | // bundle other parameters into tuple to match |
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467 | std::list< Type * > binderTypes; |
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468 | |
---|
469 | do { |
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470 | binderTypes.push_back( otherParam->get_type()->clone() ); |
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471 | ++jt; |
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472 | |
---|
473 | if ( jt == otherParams.end() ) break; |
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474 | |
---|
475 | otherParam = dynamic_cast< TypeExpr* >(*jt); |
---|
476 | assertf(otherParam, "Aggregate parameters should be type expressions"); |
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477 | } while (true); |
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478 | |
---|
479 | otherParamTy = new TupleType{ paramTy->get_qualifiers(), binderTypes }; |
---|
480 | ++it; // skip ttype parameter for break |
---|
481 | } else if ( otherTupleParam ) { |
---|
482 | // bundle parameters into tuple to match other |
---|
483 | std::list< Type * > binderTypes; |
---|
484 | |
---|
485 | do { |
---|
486 | binderTypes.push_back( param->get_type()->clone() ); |
---|
487 | ++it; |
---|
488 | |
---|
489 | if ( it == params.end() ) break; |
---|
490 | |
---|
491 | param = dynamic_cast< TypeExpr* >(*it); |
---|
492 | assertf(param, "Aggregate parameters should be type expressions"); |
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493 | } while (true); |
---|
494 | |
---|
495 | paramTy = new TupleType{ otherParamTy->get_qualifiers(), binderTypes }; |
---|
496 | ++jt; // skip ttype parameter for break |
---|
497 | } |
---|
498 | |
---|
499 | if ( ! unifyExact( paramTy, otherParamTy, env, needAssertions, haveAssertions, openVars, WidenMode(false, false), indexer ) ) { |
---|
500 | result = false; |
---|
501 | return; |
---|
502 | } |
---|
503 | |
---|
504 | // ttype parameter should be last |
---|
505 | if ( tupleParam || otherTupleParam ) break; |
---|
506 | } |
---|
507 | result = ( it == params.end() && jt == otherParams.end() ); |
---|
508 | } |
---|
509 | |
---|
510 | void Unify::postvisit(StructInstType *structInst) { |
---|
511 | handleGenericRefType( structInst, type2 ); |
---|
512 | } |
---|
513 | |
---|
514 | void Unify::postvisit(UnionInstType *unionInst) { |
---|
515 | handleGenericRefType( unionInst, type2 ); |
---|
516 | } |
---|
517 | |
---|
518 | void Unify::postvisit(EnumInstType *enumInst) { |
---|
519 | handleRefType( enumInst, type2 ); |
---|
520 | } |
---|
521 | |
---|
522 | void Unify::postvisit(TraitInstType *contextInst) { |
---|
523 | handleRefType( contextInst, type2 ); |
---|
524 | } |
---|
525 | |
---|
526 | void Unify::postvisit(TypeInstType *typeInst) { |
---|
527 | assert( openVars.find( typeInst->get_name() ) == openVars.end() ); |
---|
528 | TypeInstType *otherInst = dynamic_cast< TypeInstType* >( type2 ); |
---|
529 | if ( otherInst && typeInst->get_name() == otherInst->get_name() ) { |
---|
530 | result = true; |
---|
531 | /// } else { |
---|
532 | /// NamedTypeDecl *nt = indexer.lookupType( typeInst->get_name() ); |
---|
533 | /// if ( nt ) { |
---|
534 | /// TypeDecl *type = dynamic_cast< TypeDecl* >( nt ); |
---|
535 | /// assert( type ); |
---|
536 | /// if ( type->get_base() ) { |
---|
537 | /// result = unifyExact( type->get_base(), typeInst, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
---|
538 | /// } |
---|
539 | /// } |
---|
540 | } // if |
---|
541 | } |
---|
542 | |
---|
543 | template< typename Iterator1, typename Iterator2 > |
---|
544 | bool unifyList( Iterator1 list1Begin, Iterator1 list1End, Iterator2 list2Begin, Iterator2 list2End, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, const SymTab::Indexer &indexer ) { |
---|
545 | auto get_type = [](Type * t) { return t; }; |
---|
546 | for ( ; list1Begin != list1End && list2Begin != list2End; ++list1Begin, ++list2Begin ) { |
---|
547 | Type * t1 = *list1Begin; |
---|
548 | Type * t2 = *list2Begin; |
---|
549 | bool isTtype1 = Tuples::isTtype( t1 ); |
---|
550 | bool isTtype2 = Tuples::isTtype( t2 ); |
---|
551 | // xxx - assumes ttype must be last parameter |
---|
552 | // xxx - there may be a nice way to refactor this, but be careful because the argument positioning might matter in some cases. |
---|
553 | if ( isTtype1 && ! isTtype2 ) { |
---|
554 | // combine all of the things in list2, then unify |
---|
555 | return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
---|
556 | } else if ( isTtype2 && ! isTtype1 ) { |
---|
557 | // combine all of the things in list1, then unify |
---|
558 | return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
---|
559 | } else if ( ! unifyExact( t1, t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ) ) { |
---|
560 | return false; |
---|
561 | } // if |
---|
562 | |
---|
563 | } // for |
---|
564 | if ( list1Begin != list1End ) { |
---|
565 | // try unifying empty tuple type with ttype |
---|
566 | Type * t1 = *list1Begin; |
---|
567 | if ( Tuples::isTtype( t1 ) ) { |
---|
568 | return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
---|
569 | } else return false; |
---|
570 | } else if ( list2Begin != list2End ) { |
---|
571 | // try unifying empty tuple type with ttype |
---|
572 | Type * t2 = *list2Begin; |
---|
573 | if ( Tuples::isTtype( t2 ) ) { |
---|
574 | return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ); |
---|
575 | } else return false; |
---|
576 | } else { |
---|
577 | return true; |
---|
578 | } // if |
---|
579 | } |
---|
580 | |
---|
581 | void Unify::postvisit(TupleType *tupleType) { |
---|
582 | if ( TupleType *otherTuple = dynamic_cast< TupleType* >( type2 ) ) { |
---|
583 | TupleType* flat1 = tupleType->clone(); |
---|
584 | TupleType* flat2 = otherTuple->clone(); |
---|
585 | std::list<Type *> types1, types2; |
---|
586 | |
---|
587 | PassVisitor<TtypeExpander> expander( env ); |
---|
588 | flat1->acceptMutator( expander ); |
---|
589 | flat2->acceptMutator( expander ); |
---|
590 | |
---|
591 | flatten( flat1, back_inserter( types1 ) ); |
---|
592 | flatten( flat2, back_inserter( types2 ) ); |
---|
593 | |
---|
594 | result = unifyList( types1.begin(), types1.end(), types2.begin(), types2.end(), env, needAssertions, haveAssertions, openVars, indexer ); |
---|
595 | } // if |
---|
596 | } |
---|
597 | |
---|
598 | void Unify::postvisit( __attribute__((unused)) VarArgsType *varArgsType ) { |
---|
599 | result = dynamic_cast< VarArgsType* >( type2 ); |
---|
600 | } |
---|
601 | |
---|
602 | void Unify::postvisit( __attribute__((unused)) ZeroType *zeroType ) { |
---|
603 | result = dynamic_cast< ZeroType* >( type2 ); |
---|
604 | } |
---|
605 | |
---|
606 | void Unify::postvisit( __attribute__((unused)) OneType *oneType ) { |
---|
607 | result = dynamic_cast< OneType* >( type2 ); |
---|
608 | } |
---|
609 | |
---|
610 | // xxx - compute once and store in the FunctionType? |
---|
611 | Type * extractResultType( FunctionType * function ) { |
---|
612 | if ( function->get_returnVals().size() == 0 ) { |
---|
613 | return new VoidType( Type::Qualifiers() ); |
---|
614 | } else if ( function->get_returnVals().size() == 1 ) { |
---|
615 | return function->get_returnVals().front()->get_type()->clone(); |
---|
616 | } else { |
---|
617 | std::list< Type * > types; |
---|
618 | for ( DeclarationWithType * decl : function->get_returnVals() ) { |
---|
619 | types.push_back( decl->get_type()->clone() ); |
---|
620 | } // for |
---|
621 | return new TupleType( Type::Qualifiers(), types ); |
---|
622 | } |
---|
623 | } |
---|
624 | } // namespace ResolvExpr |
---|
625 | |
---|
626 | // Local Variables: // |
---|
627 | // tab-width: 4 // |
---|
628 | // mode: c++ // |
---|
629 | // compile-command: "make install" // |
---|
630 | // End: // |
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