[a32b204] | 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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[6ed1d4b] | 7 | // AlternativeFinder.cc -- |
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[a32b204] | 8 | // |
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| 9 | // Author : Richard C. Bilson |
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| 10 | // Created On : Sat May 16 23:52:08 2015 |
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[7d01cf44] | 11 | // Last Modified By : Andrew Beach |
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| 12 | // Last Modified On : Thu Aug 8 16:35:00 2019 |
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| 13 | // Update Count : 38 |
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[a32b204] | 14 | // |
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| 15 | |
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[ea6332d] | 16 | #include <algorithm> // for copy |
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[e3e16bc] | 17 | #include <cassert> // for strict_dynamic_cast, assert, assertf |
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[403b388] | 18 | #include <cstddef> // for size_t |
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[ea6332d] | 19 | #include <iostream> // for operator<<, cerr, ostream, endl |
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| 20 | #include <iterator> // for back_insert_iterator, back_inserter |
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| 21 | #include <list> // for _List_iterator, list, _List_const_... |
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| 22 | #include <map> // for _Rb_tree_iterator, map, _Rb_tree_c... |
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[403b388] | 23 | #include <memory> // for allocator_traits<>::value_type, unique_ptr |
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[ea6332d] | 24 | #include <utility> // for pair |
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[aeb75b1] | 25 | #include <vector> // for vector |
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[51b7345] | 26 | |
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[3bbd012] | 27 | #include "CompilationState.h" // for resolvep |
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[ea6332d] | 28 | #include "Alternative.h" // for AltList, Alternative |
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[51b7345] | 29 | #include "AlternativeFinder.h" |
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[d76c588] | 30 | #include "AST/Expr.hpp" |
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[4b7cce6] | 31 | #include "AST/SymbolTable.hpp" |
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[d76c588] | 32 | #include "AST/Type.hpp" |
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[ea6332d] | 33 | #include "Common/SemanticError.h" // for SemanticError |
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| 34 | #include "Common/utility.h" // for deleteAll, printAll, CodeLocation |
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| 35 | #include "Cost.h" // for Cost, Cost::zero, operator<<, Cost... |
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[a8b27c6] | 36 | #include "ExplodedActual.h" // for ExplodedActual |
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[ea6332d] | 37 | #include "InitTweak/InitTweak.h" // for getFunctionName |
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| 38 | #include "RenameVars.h" // for RenameVars, global_renamer |
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[6d6e829] | 39 | #include "ResolveAssertions.h" // for resolveAssertions |
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[ea6332d] | 40 | #include "ResolveTypeof.h" // for resolveTypeof |
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| 41 | #include "Resolver.h" // for resolveStmtExpr |
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| 42 | #include "SymTab/Indexer.h" // for Indexer |
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| 43 | #include "SymTab/Mangler.h" // for Mangler |
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[9939dc3] | 44 | #include "SymTab/ValidateType.h" // for validateType |
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[ea6332d] | 45 | #include "SynTree/Constant.h" // for Constant |
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| 46 | #include "SynTree/Declaration.h" // for DeclarationWithType, TypeDecl, Dec... |
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| 47 | #include "SynTree/Expression.h" // for Expression, CastExpr, NameExpr |
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| 48 | #include "SynTree/Initializer.h" // for SingleInit, operator<<, Designation |
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| 49 | #include "SynTree/SynTree.h" // for UniqueId |
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| 50 | #include "SynTree/Type.h" // for Type, FunctionType, PointerType |
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| 51 | #include "Tuples/Explode.h" // for explode |
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| 52 | #include "Tuples/Tuples.h" // for isTtype, handleTupleAssignment |
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| 53 | #include "Unify.h" // for unify |
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| 54 | #include "typeops.h" // for adjustExprType, polyCost, castCost |
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[51b7345] | 55 | |
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[6ed1d4b] | 56 | #define PRINT( text ) if ( resolvep ) { text } |
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[51b7345] | 57 | //#define DEBUG_COST |
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| 58 | |
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| 59 | namespace ResolvExpr { |
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[13deae88] | 60 | struct AlternativeFinder::Finder : public WithShortCircuiting { |
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| 61 | Finder( AlternativeFinder & altFinder ) : altFinder( altFinder ), indexer( altFinder.indexer ), alternatives( altFinder.alternatives ), env( altFinder.env ), targetType( altFinder.targetType ) {} |
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| 62 | |
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| 63 | void previsit( BaseSyntaxNode * ) { visit_children = false; } |
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| 64 | |
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| 65 | void postvisit( ApplicationExpr * applicationExpr ); |
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| 66 | void postvisit( UntypedExpr * untypedExpr ); |
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| 67 | void postvisit( AddressExpr * addressExpr ); |
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| 68 | void postvisit( LabelAddressExpr * labelExpr ); |
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| 69 | void postvisit( CastExpr * castExpr ); |
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| 70 | void postvisit( VirtualCastExpr * castExpr ); |
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[3b0c8cb] | 71 | void postvisit( KeywordCastExpr * castExpr ); |
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[13deae88] | 72 | void postvisit( UntypedMemberExpr * memberExpr ); |
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| 73 | void postvisit( MemberExpr * memberExpr ); |
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| 74 | void postvisit( NameExpr * variableExpr ); |
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| 75 | void postvisit( VariableExpr * variableExpr ); |
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| 76 | void postvisit( ConstantExpr * constantExpr ); |
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| 77 | void postvisit( SizeofExpr * sizeofExpr ); |
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| 78 | void postvisit( AlignofExpr * alignofExpr ); |
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| 79 | void postvisit( UntypedOffsetofExpr * offsetofExpr ); |
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| 80 | void postvisit( OffsetofExpr * offsetofExpr ); |
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| 81 | void postvisit( OffsetPackExpr * offsetPackExpr ); |
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| 82 | void postvisit( LogicalExpr * logicalExpr ); |
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| 83 | void postvisit( ConditionalExpr * conditionalExpr ); |
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| 84 | void postvisit( CommaExpr * commaExpr ); |
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| 85 | void postvisit( ImplicitCopyCtorExpr * impCpCtorExpr ); |
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| 86 | void postvisit( ConstructorExpr * ctorExpr ); |
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| 87 | void postvisit( RangeExpr * rangeExpr ); |
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| 88 | void postvisit( UntypedTupleExpr * tupleExpr ); |
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| 89 | void postvisit( TupleExpr * tupleExpr ); |
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| 90 | void postvisit( TupleIndexExpr * tupleExpr ); |
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| 91 | void postvisit( TupleAssignExpr * tupleExpr ); |
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| 92 | void postvisit( UniqueExpr * unqExpr ); |
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| 93 | void postvisit( StmtExpr * stmtExpr ); |
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| 94 | void postvisit( UntypedInitExpr * initExpr ); |
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[c71b256] | 95 | void postvisit( InitExpr * initExpr ); |
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| 96 | void postvisit( DeletedExpr * delExpr ); |
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[d807ca28] | 97 | void postvisit( GenericExpr * genExpr ); |
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[13deae88] | 98 | |
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| 99 | /// Adds alternatives for anonymous members |
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| 100 | void addAnonConversions( const Alternative & alt ); |
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| 101 | /// Adds alternatives for member expressions, given the aggregate, conversion cost for that aggregate, and name of the member |
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[6d6e829] | 102 | template< typename StructOrUnionType > void addAggMembers( StructOrUnionType *aggInst, Expression *expr, const Alternative &alt, const Cost &newCost, const std::string & name ); |
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[13deae88] | 103 | /// Adds alternatives for member expressions where the left side has tuple type |
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[6d6e829] | 104 | void addTupleMembers( TupleType *tupleType, Expression *expr, const Alternative &alt, const Cost &newCost, Expression *member ); |
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[13deae88] | 105 | /// Adds alternatives for offsetof expressions, given the base type and name of the member |
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| 106 | template< typename StructOrUnionType > void addOffsetof( StructOrUnionType *aggInst, const std::string &name ); |
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| 107 | /// Takes a final result and checks if its assertions can be satisfied |
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| 108 | template<typename OutputIterator> |
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| 109 | void validateFunctionAlternative( const Alternative &func, ArgPack& result, const std::vector<ArgPack>& results, OutputIterator out ); |
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| 110 | /// Finds matching alternatives for a function, given a set of arguments |
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| 111 | template<typename OutputIterator> |
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[432ce7a] | 112 | void makeFunctionAlternatives( const Alternative &func, FunctionType *funcType, const ExplodedArgs_old& args, OutputIterator out ); |
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[0b00df0] | 113 | /// Sets up parameter inference for an output alternative |
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[13deae88] | 114 | template< typename OutputIterator > |
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[0b00df0] | 115 | void inferParameters( Alternative &newAlt, OutputIterator out ); |
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[13deae88] | 116 | private: |
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| 117 | AlternativeFinder & altFinder; |
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| 118 | const SymTab::Indexer &indexer; |
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| 119 | AltList & alternatives; |
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| 120 | const TypeEnvironment &env; |
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| 121 | Type *& targetType; |
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| 122 | }; |
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| 123 | |
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[908cc83] | 124 | Cost sumCost( const AltList &in ) { |
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[89be1c68] | 125 | Cost total = Cost::zero; |
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[908cc83] | 126 | for ( AltList::const_iterator i = in.begin(); i != in.end(); ++i ) { |
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| 127 | total += i->cost; |
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| 128 | } |
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| 129 | return total; |
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| 130 | } |
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| 131 | |
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[1e8bbac9] | 132 | void printAlts( const AltList &list, std::ostream &os, unsigned int indentAmt ) { |
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[2595df1] | 133 | std::vector<std::string> sorted; |
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| 134 | sorted.reserve(list.size()); |
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| 135 | for(const auto & c : list) { |
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| 136 | std::stringstream ss; |
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[3233b91] | 137 | c.print( ss, indentAmt ); |
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[2595df1] | 138 | sorted.push_back(ss.str()); |
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| 139 | } |
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[1db306a] | 140 | |
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[2595df1] | 141 | std::sort(sorted.begin(), sorted.end()); |
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[1db306a] | 142 | |
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[2595df1] | 143 | for ( const auto & s : sorted ) { |
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| 144 | os << s << std::endl; |
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[a32b204] | 145 | } |
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[1e8bbac9] | 146 | } |
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[d9a0e76] | 147 | |
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[1e8bbac9] | 148 | namespace { |
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[a32b204] | 149 | void makeExprList( const AltList &in, std::list< Expression* > &out ) { |
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| 150 | for ( AltList::const_iterator i = in.begin(); i != in.end(); ++i ) { |
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| 151 | out.push_back( i->expr->clone() ); |
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| 152 | } |
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| 153 | } |
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[d9a0e76] | 154 | |
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[a32b204] | 155 | struct PruneStruct { |
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| 156 | bool isAmbiguous; |
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| 157 | AltList::iterator candidate; |
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| 158 | PruneStruct() {} |
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| 159 | PruneStruct( AltList::iterator candidate ): isAmbiguous( false ), candidate( candidate ) {} |
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| 160 | }; |
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| 161 | |
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[0f19d763] | 162 | /// Prunes a list of alternatives down to those that have the minimum conversion cost for a given return type; skips ambiguous interpretations |
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[a32b204] | 163 | template< typename InputIterator, typename OutputIterator > |
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[d7dc824] | 164 | void pruneAlternatives( InputIterator begin, InputIterator end, OutputIterator out ) { |
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[a32b204] | 165 | // select the alternatives that have the minimum conversion cost for a particular set of result types |
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| 166 | std::map< std::string, PruneStruct > selected; |
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| 167 | for ( AltList::iterator candidate = begin; candidate != end; ++candidate ) { |
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| 168 | PruneStruct current( candidate ); |
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| 169 | std::string mangleName; |
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[906e24d] | 170 | { |
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| 171 | Type * newType = candidate->expr->get_result()->clone(); |
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[a32b204] | 172 | candidate->env.apply( newType ); |
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[906e24d] | 173 | mangleName = SymTab::Mangler::mangle( newType ); |
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[a32b204] | 174 | delete newType; |
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| 175 | } |
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| 176 | std::map< std::string, PruneStruct >::iterator mapPlace = selected.find( mangleName ); |
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| 177 | if ( mapPlace != selected.end() ) { |
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| 178 | if ( candidate->cost < mapPlace->second.candidate->cost ) { |
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| 179 | PRINT( |
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[6ed1d4b] | 180 | std::cerr << "cost " << candidate->cost << " beats " << mapPlace->second.candidate->cost << std::endl; |
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[7c64920] | 181 | ) |
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[0f19d763] | 182 | selected[ mangleName ] = current; |
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[a32b204] | 183 | } else if ( candidate->cost == mapPlace->second.candidate->cost ) { |
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[630bcb5] | 184 | // if one of the candidates contains a deleted identifier, can pick the other, since |
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| 185 | // deleted expressions should not be ambiguous if there is another option that is at least as good |
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| 186 | if ( findDeletedExpr( candidate->expr ) ) { |
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| 187 | // do nothing |
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| 188 | PRINT( std::cerr << "candidate is deleted" << std::endl; ) |
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| 189 | } else if ( findDeletedExpr( mapPlace->second.candidate->expr ) ) { |
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| 190 | PRINT( std::cerr << "current is deleted" << std::endl; ) |
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| 191 | selected[ mangleName ] = current; |
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| 192 | } else { |
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| 193 | PRINT( |
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| 194 | std::cerr << "marking ambiguous" << std::endl; |
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| 195 | ) |
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| 196 | mapPlace->second.isAmbiguous = true; |
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| 197 | } |
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[b0837e4] | 198 | } else { |
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| 199 | PRINT( |
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| 200 | std::cerr << "cost " << candidate->cost << " loses to " << mapPlace->second.candidate->cost << std::endl; |
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| 201 | ) |
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[a32b204] | 202 | } |
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| 203 | } else { |
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| 204 | selected[ mangleName ] = current; |
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| 205 | } |
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| 206 | } |
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[d9a0e76] | 207 | |
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[0f19d763] | 208 | // accept the alternatives that were unambiguous |
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| 209 | for ( std::map< std::string, PruneStruct >::iterator target = selected.begin(); target != selected.end(); ++target ) { |
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| 210 | if ( ! target->second.isAmbiguous ) { |
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| 211 | Alternative &alt = *target->second.candidate; |
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[906e24d] | 212 | alt.env.applyFree( alt.expr->get_result() ); |
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[0f19d763] | 213 | *out++ = alt; |
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[a32b204] | 214 | } |
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[0f19d763] | 215 | } |
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[d9a0e76] | 216 | } |
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[a32b204] | 217 | |
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| 218 | void renameTypes( Expression *expr ) { |
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[ad51cc2] | 219 | renameTyVars( expr->result ); |
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[e76acbe] | 220 | } |
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[1dcd9554] | 221 | } // namespace |
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[b1bead1] | 222 | |
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[a181494] | 223 | void referenceToRvalueConversion( Expression *& expr, Cost & cost ) { |
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[1dcd9554] | 224 | if ( dynamic_cast< ReferenceType * >( expr->get_result() ) ) { |
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| 225 | // cast away reference from expr |
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| 226 | expr = new CastExpr( expr, expr->get_result()->stripReferences()->clone() ); |
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[a181494] | 227 | cost.incReference(); |
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[b1bead1] | 228 | } |
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[1dcd9554] | 229 | } |
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[d9a0e76] | 230 | |
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[a32b204] | 231 | template< typename InputIterator, typename OutputIterator > |
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| 232 | void AlternativeFinder::findSubExprs( InputIterator begin, InputIterator end, OutputIterator out ) { |
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| 233 | while ( begin != end ) { |
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| 234 | AlternativeFinder finder( indexer, env ); |
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| 235 | finder.findWithAdjustment( *begin ); |
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| 236 | // XXX either this |
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| 237 | //Designators::fixDesignations( finder, (*begin++)->get_argName() ); |
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| 238 | // or XXX this |
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| 239 | begin++; |
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| 240 | PRINT( |
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[6ed1d4b] | 241 | std::cerr << "findSubExprs" << std::endl; |
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| 242 | printAlts( finder.alternatives, std::cerr ); |
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[7c64920] | 243 | ) |
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[0f19d763] | 244 | *out++ = finder; |
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[a32b204] | 245 | } |
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[d9a0e76] | 246 | } |
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| 247 | |
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[a32b204] | 248 | AlternativeFinder::AlternativeFinder( const SymTab::Indexer &indexer, const TypeEnvironment &env ) |
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| 249 | : indexer( indexer ), env( env ) { |
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[d9a0e76] | 250 | } |
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[51b7345] | 251 | |
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[59cf83b] | 252 | void AlternativeFinder::find( Expression *expr, ResolvMode mode ) { |
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[13deae88] | 253 | PassVisitor<Finder> finder( *this ); |
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| 254 | expr->accept( finder ); |
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[59cf83b] | 255 | if ( mode.failFast && alternatives.empty() ) { |
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[83882e9] | 256 | PRINT( |
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| 257 | std::cerr << "No reasonable alternatives for expression " << expr << std::endl; |
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| 258 | ) |
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[a16764a6] | 259 | SemanticError( expr, "No reasonable alternatives for expression " ); |
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[a32b204] | 260 | } |
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[1389810] | 261 | if ( mode.prune ) { |
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[6d6e829] | 262 | // trim candidates just to those where the assertions resolve |
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[fbecee5] | 263 | // - necessary pre-requisite to pruning |
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[6d6e829] | 264 | AltList candidates; |
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[4d2d45f9] | 265 | std::list<std::string> errors; |
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[6d6e829] | 266 | for ( unsigned i = 0; i < alternatives.size(); ++i ) { |
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[4d2d45f9] | 267 | resolveAssertions( alternatives[i], indexer, candidates, errors ); |
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[6d6e829] | 268 | } |
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| 269 | // fail early if none such |
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| 270 | if ( mode.failFast && candidates.empty() ) { |
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| 271 | std::ostringstream stream; |
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[4d2d45f9] | 272 | stream << "No alternatives with satisfiable assertions for " << expr << "\n"; |
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| 273 | // << "Alternatives with failing assertions are:\n"; |
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| 274 | // printAlts( alternatives, stream, 1 ); |
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| 275 | for ( const auto& err : errors ) { |
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| 276 | stream << err; |
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| 277 | } |
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[6d6e829] | 278 | SemanticError( expr->location, stream.str() ); |
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| 279 | } |
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| 280 | // reset alternatives |
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| 281 | alternatives = std::move( candidates ); |
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| 282 | } |
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[59cf83b] | 283 | if ( mode.prune ) { |
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[b0837e4] | 284 | auto oldsize = alternatives.size(); |
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[b6fe7e6] | 285 | PRINT( |
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| 286 | std::cerr << "alternatives before prune:" << std::endl; |
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| 287 | printAlts( alternatives, std::cerr ); |
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| 288 | ) |
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[bd4f2e9] | 289 | AltList pruned; |
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| 290 | pruneAlternatives( alternatives.begin(), alternatives.end(), back_inserter( pruned ) ); |
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[59cf83b] | 291 | if ( mode.failFast && pruned.empty() ) { |
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[b6fe7e6] | 292 | std::ostringstream stream; |
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| 293 | AltList winners; |
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| 294 | findMinCost( alternatives.begin(), alternatives.end(), back_inserter( winners ) ); |
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[50377a4] | 295 | stream << "Cannot choose between " << winners.size() << " alternatives for expression\n"; |
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[5a824c2] | 296 | expr->print( stream ); |
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[93401f8] | 297 | stream << " Alternatives are:\n"; |
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[50377a4] | 298 | printAlts( winners, stream, 1 ); |
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[a16764a6] | 299 | SemanticError( expr->location, stream.str() ); |
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[b6fe7e6] | 300 | } |
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[bd4f2e9] | 301 | alternatives = move(pruned); |
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[b0837e4] | 302 | PRINT( |
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| 303 | std::cerr << "there are " << oldsize << " alternatives before elimination" << std::endl; |
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| 304 | ) |
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[b6fe7e6] | 305 | PRINT( |
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| 306 | std::cerr << "there are " << alternatives.size() << " alternatives after elimination" << std::endl; |
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| 307 | ) |
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[a32b204] | 308 | } |
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[954ef5b] | 309 | // adjust types after pruning so that types substituted by pruneAlternatives are correctly adjusted |
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[59cf83b] | 310 | if ( mode.adjust ) { |
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| 311 | for ( Alternative& i : alternatives ) { |
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| 312 | adjustExprType( i.expr->get_result(), i.env, indexer ); |
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[954ef5b] | 313 | } |
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| 314 | } |
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[8e9cbb2] | 315 | |
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[64ac636] | 316 | // Central location to handle gcc extension keyword, etc. for all expression types. |
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[8e9cbb2] | 317 | for ( Alternative &iter: alternatives ) { |
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| 318 | iter.expr->set_extension( expr->get_extension() ); |
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[64ac636] | 319 | iter.expr->location = expr->location; |
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[8e9cbb2] | 320 | } // for |
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[0f19d763] | 321 | } |
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[d9a0e76] | 322 | |
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[4e66a18] | 323 | void AlternativeFinder::findWithAdjustment( Expression *expr ) { |
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[59cf83b] | 324 | find( expr, ResolvMode::withAdjustment() ); |
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[4e66a18] | 325 | } |
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| 326 | |
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| 327 | void AlternativeFinder::findWithoutPrune( Expression * expr ) { |
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[59cf83b] | 328 | find( expr, ResolvMode::withoutPrune() ); |
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[4e66a18] | 329 | } |
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| 330 | |
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| 331 | void AlternativeFinder::maybeFind( Expression * expr ) { |
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[59cf83b] | 332 | find( expr, ResolvMode::withoutFailFast() ); |
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[d9a0e76] | 333 | } |
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[a32b204] | 334 | |
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[13deae88] | 335 | void AlternativeFinder::Finder::addAnonConversions( const Alternative & alt ) { |
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[4b0f997] | 336 | // adds anonymous member interpretations whenever an aggregate value type is seen. |
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[d1685588] | 337 | // it's okay for the aggregate expression to have reference type -- cast it to the base type to treat the aggregate as the referenced value |
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| 338 | std::unique_ptr<Expression> aggrExpr( alt.expr->clone() ); |
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[25fcb84] | 339 | alt.env.apply( aggrExpr->result ); |
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| 340 | Type * aggrType = aggrExpr->result; |
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[d1685588] | 341 | if ( dynamic_cast< ReferenceType * >( aggrType ) ) { |
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| 342 | aggrType = aggrType->stripReferences(); |
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| 343 | aggrExpr.reset( new CastExpr( aggrExpr.release(), aggrType->clone() ) ); |
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| 344 | } |
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| 345 | |
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[6f096d2] | 346 | if ( StructInstType * structInst = dynamic_cast< StructInstType* >( aggrExpr->result ) ) { |
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[6d6e829] | 347 | addAggMembers( structInst, aggrExpr.get(), alt, alt.cost+Cost::safe, "" ); |
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[6f096d2] | 348 | } else if ( UnionInstType * unionInst = dynamic_cast< UnionInstType* >( aggrExpr->result ) ) { |
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[6d6e829] | 349 | addAggMembers( unionInst, aggrExpr.get(), alt, alt.cost+Cost::safe, "" ); |
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[4b0f997] | 350 | } // if |
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| 351 | } |
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[77971f6] | 352 | |
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[a32b204] | 353 | template< typename StructOrUnionType > |
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[6f096d2] | 354 | void AlternativeFinder::Finder::addAggMembers( StructOrUnionType * aggInst, Expression * expr, const Alternative& alt, const Cost &newCost, const std::string & name ) { |
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[bf32bb8] | 355 | std::list< Declaration* > members; |
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| 356 | aggInst->lookup( name, members ); |
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[4b0f997] | 357 | |
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[5de1e2c] | 358 | for ( Declaration * decl : members ) { |
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[6f096d2] | 359 | if ( DeclarationWithType * dwt = dynamic_cast< DeclarationWithType* >( decl ) ) { |
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[5de1e2c] | 360 | // addAnonAlternatives uses vector::push_back, which invalidates references to existing elements, so |
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| 361 | // can't construct in place and use vector::back |
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[6d6e829] | 362 | Alternative newAlt{ alt, new MemberExpr{ dwt, expr->clone() }, newCost }; |
---|
[5de1e2c] | 363 | renameTypes( newAlt.expr ); |
---|
| 364 | addAnonConversions( newAlt ); // add anonymous member interpretations whenever an aggregate value type is seen as a member expression. |
---|
| 365 | alternatives.push_back( std::move(newAlt) ); |
---|
[bf32bb8] | 366 | } else { |
---|
| 367 | assert( false ); |
---|
[a32b204] | 368 | } |
---|
| 369 | } |
---|
[d9a0e76] | 370 | } |
---|
[a32b204] | 371 | |
---|
[6f096d2] | 372 | void AlternativeFinder::Finder::addTupleMembers( TupleType * tupleType, Expression * expr, const Alternative &alt, const Cost &newCost, Expression * member ) { |
---|
[848ce71] | 373 | if ( ConstantExpr * constantExpr = dynamic_cast< ConstantExpr * >( member ) ) { |
---|
| 374 | // get the value of the constant expression as an int, must be between 0 and the length of the tuple type to have meaning |
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[2a6c115] | 375 | auto val = constantExpr->intValue(); |
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[848ce71] | 376 | std::string tmp; |
---|
[2a6c115] | 377 | if ( val >= 0 && (unsigned long long)val < tupleType->size() ) { |
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[6f096d2] | 378 | alternatives.push_back( Alternative{ |
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[6d6e829] | 379 | alt, new TupleIndexExpr( expr->clone(), val ), newCost } ); |
---|
[2a6c115] | 380 | } // if |
---|
[848ce71] | 381 | } // if |
---|
| 382 | } |
---|
| 383 | |
---|
[6f096d2] | 384 | void AlternativeFinder::Finder::postvisit( ApplicationExpr * applicationExpr ) { |
---|
[6d6e829] | 385 | alternatives.push_back( Alternative{ applicationExpr->clone(), env } ); |
---|
[d9a0e76] | 386 | } |
---|
| 387 | |
---|
[7d01cf44] | 388 | Cost computeConversionCost( Type * actualType, Type * formalType, bool actualIsLvalue, |
---|
| 389 | const SymTab::Indexer &indexer, const TypeEnvironment & env ) { |
---|
[ddf8a29] | 390 | PRINT( |
---|
| 391 | std::cerr << std::endl << "converting "; |
---|
| 392 | actualType->print( std::cerr, 8 ); |
---|
| 393 | std::cerr << std::endl << " to "; |
---|
| 394 | formalType->print( std::cerr, 8 ); |
---|
| 395 | std::cerr << std::endl << "environment is: "; |
---|
| 396 | env.print( std::cerr, 8 ); |
---|
| 397 | std::cerr << std::endl; |
---|
| 398 | ) |
---|
[7d01cf44] | 399 | Cost convCost = conversionCost( actualType, formalType, actualIsLvalue, indexer, env ); |
---|
[ddf8a29] | 400 | PRINT( |
---|
[d06c808] | 401 | std::cerr << std::endl << "cost is " << convCost << std::endl; |
---|
[ddf8a29] | 402 | ) |
---|
| 403 | if ( convCost == Cost::infinity ) { |
---|
| 404 | return convCost; |
---|
| 405 | } |
---|
| 406 | convCost.incPoly( polyCost( formalType, env, indexer ) + polyCost( actualType, env, indexer ) ); |
---|
[d06c808] | 407 | PRINT( |
---|
| 408 | std::cerr << "cost with polycost is " << convCost << std::endl; |
---|
| 409 | ) |
---|
[ddf8a29] | 410 | return convCost; |
---|
| 411 | } |
---|
| 412 | |
---|
| 413 | Cost computeExpressionConversionCost( Expression *& actualExpr, Type * formalType, const SymTab::Indexer &indexer, const TypeEnvironment & env ) { |
---|
[7d01cf44] | 414 | Cost convCost = computeConversionCost( |
---|
| 415 | actualExpr->result, formalType, actualExpr->get_lvalue(), indexer, env ); |
---|
[ddf8a29] | 416 | |
---|
[bb666f64] | 417 | // if there is a non-zero conversion cost, ignoring poly cost, then the expression requires conversion. |
---|
| 418 | // ignore poly cost for now, since this requires resolution of the cast to infer parameters and this |
---|
| 419 | // does not currently work for the reason stated below. |
---|
[ddf8a29] | 420 | Cost tmpCost = convCost; |
---|
| 421 | tmpCost.incPoly( -tmpCost.get_polyCost() ); |
---|
| 422 | if ( tmpCost != Cost::zero ) { |
---|
| 423 | Type *newType = formalType->clone(); |
---|
| 424 | env.apply( newType ); |
---|
| 425 | actualExpr = new CastExpr( actualExpr, newType ); |
---|
| 426 | // xxx - SHOULD be able to resolve this cast, but at the moment pointers are not castable to zero_t, but are implicitly convertible. This is clearly |
---|
| 427 | // inconsistent, once this is fixed it should be possible to resolve the cast. |
---|
| 428 | // xxx - this isn't working, it appears because type1 (the formal type) is seen as widenable, but it shouldn't be, because this makes the conversion from DT* to DT* since commontype(zero_t, DT*) is DT*, rather than just nothing. |
---|
| 429 | |
---|
| 430 | // AlternativeFinder finder( indexer, env ); |
---|
| 431 | // finder.findWithAdjustment( actualExpr ); |
---|
| 432 | // assertf( finder.get_alternatives().size() > 0, "Somehow castable expression failed to find alternatives." ); |
---|
| 433 | // assertf( finder.get_alternatives().size() == 1, "Somehow got multiple alternatives for known cast expression." ); |
---|
| 434 | // Alternative & alt = finder.get_alternatives().front(); |
---|
| 435 | // delete actualExpr; |
---|
| 436 | // actualExpr = alt.expr->clone(); |
---|
| 437 | } |
---|
| 438 | return convCost; |
---|
| 439 | } |
---|
| 440 | |
---|
| 441 | Cost computeApplicationConversionCost( Alternative &alt, const SymTab::Indexer &indexer ) { |
---|
[e3e16bc] | 442 | ApplicationExpr *appExpr = strict_dynamic_cast< ApplicationExpr* >( alt.expr ); |
---|
[1dd1bd2] | 443 | PointerType *pointer = strict_dynamic_cast< PointerType* >( appExpr->function->result ); |
---|
| 444 | FunctionType *function = strict_dynamic_cast< FunctionType* >( pointer->base ); |
---|
[a32b204] | 445 | |
---|
[89be1c68] | 446 | Cost convCost = Cost::zero; |
---|
[1dd1bd2] | 447 | std::list< DeclarationWithType* >& formals = function->parameters; |
---|
[a32b204] | 448 | std::list< DeclarationWithType* >::iterator formal = formals.begin(); |
---|
[1dd1bd2] | 449 | std::list< Expression* >& actuals = appExpr->args; |
---|
[0362d42] | 450 | |
---|
[1dd1bd2] | 451 | for ( Expression*& actualExpr : actuals ) { |
---|
| 452 | Type * actualType = actualExpr->result; |
---|
[a32b204] | 453 | PRINT( |
---|
[6ed1d4b] | 454 | std::cerr << "actual expression:" << std::endl; |
---|
[1dd1bd2] | 455 | actualExpr->print( std::cerr, 8 ); |
---|
[6ed1d4b] | 456 | std::cerr << "--- results are" << std::endl; |
---|
[53e3b4a] | 457 | actualType->print( std::cerr, 8 ); |
---|
[7c64920] | 458 | ) |
---|
[53e3b4a] | 459 | if ( formal == formals.end() ) { |
---|
[1dd1bd2] | 460 | if ( function->isVarArgs ) { |
---|
[89be1c68] | 461 | convCost.incUnsafe(); |
---|
[d06c808] | 462 | PRINT( std::cerr << "end of formals with varargs function: inc unsafe: " << convCost << std::endl; ; ) |
---|
[b1bead1] | 463 | // convert reference-typed expressions to value-typed expressions |
---|
[1dd1bd2] | 464 | referenceToRvalueConversion( actualExpr, convCost ); |
---|
[53e3b4a] | 465 | continue; |
---|
| 466 | } else { |
---|
| 467 | return Cost::infinity; |
---|
[7c64920] | 468 | } |
---|
[53e3b4a] | 469 | } |
---|
[1dd1bd2] | 470 | if ( DefaultArgExpr * def = dynamic_cast< DefaultArgExpr * >( actualExpr ) ) { |
---|
[0f79853] | 471 | // default arguments should be free - don't include conversion cost. |
---|
| 472 | // Unwrap them here because they are not relevant to the rest of the system. |
---|
[1dd1bd2] | 473 | actualExpr = def->expr; |
---|
[0f79853] | 474 | ++formal; |
---|
| 475 | continue; |
---|
| 476 | } |
---|
[1dd1bd2] | 477 | // mark conversion cost to formal and also specialization cost of formal type |
---|
[53e3b4a] | 478 | Type * formalType = (*formal)->get_type(); |
---|
[1dd1bd2] | 479 | convCost += computeExpressionConversionCost( actualExpr, formalType, indexer, alt.env ); |
---|
| 480 | convCost.decSpec( specCost( formalType ) ); |
---|
[53e3b4a] | 481 | ++formal; // can't be in for-loop update because of the continue |
---|
[d9a0e76] | 482 | } |
---|
[a32b204] | 483 | if ( formal != formals.end() ) { |
---|
| 484 | return Cost::infinity; |
---|
[d9a0e76] | 485 | } |
---|
| 486 | |
---|
[6f096d2] | 487 | // specialization cost of return types can't be accounted for directly, it disables |
---|
[bd78797] | 488 | // otherwise-identical calls, like this example based on auto-newline in the I/O lib: |
---|
| 489 | // |
---|
| 490 | // forall(otype OS) { |
---|
| 491 | // void ?|?(OS&, int); // with newline |
---|
| 492 | // OS& ?|?(OS&, int); // no newline, always chosen due to more specialization |
---|
| 493 | // } |
---|
[1dd1bd2] | 494 | |
---|
| 495 | // mark type variable and specialization cost of forall clause |
---|
| 496 | convCost.incVar( function->forall.size() ); |
---|
| 497 | for ( TypeDecl* td : function->forall ) { |
---|
| 498 | convCost.decSpec( td->assertions.size() ); |
---|
| 499 | } |
---|
| 500 | |
---|
[a32b204] | 501 | return convCost; |
---|
| 502 | } |
---|
[d9a0e76] | 503 | |
---|
[8c84ebd] | 504 | /// Adds type variables to the open variable set and marks their assertions |
---|
[a32b204] | 505 | void makeUnifiableVars( Type *type, OpenVarSet &unifiableVars, AssertionSet &needAssertions ) { |
---|
[43bd69d] | 506 | for ( Type::ForallList::const_iterator tyvar = type->forall.begin(); tyvar != type->forall.end(); ++tyvar ) { |
---|
[2c57025] | 507 | unifiableVars[ (*tyvar)->get_name() ] = TypeDecl::Data{ *tyvar }; |
---|
[43bd69d] | 508 | for ( std::list< DeclarationWithType* >::iterator assert = (*tyvar)->assertions.begin(); assert != (*tyvar)->assertions.end(); ++assert ) { |
---|
[6c3a988f] | 509 | needAssertions[ *assert ].isUsed = true; |
---|
[a32b204] | 510 | } |
---|
[d9a0e76] | 511 | } |
---|
| 512 | } |
---|
[a32b204] | 513 | |
---|
[9d5089e] | 514 | /// Unique identifier for matching expression resolutions to their requesting expression (located in CandidateFinder.cpp) |
---|
| 515 | extern UniqueId globalResnSlot; |
---|
[0b00df0] | 516 | |
---|
[a32b204] | 517 | template< typename OutputIterator > |
---|
[0b00df0] | 518 | void AlternativeFinder::Finder::inferParameters( Alternative &newAlt, OutputIterator out ) { |
---|
| 519 | // Set need bindings for any unbound assertions |
---|
| 520 | UniqueId crntResnSlot = 0; // matching ID for this expression's assertions |
---|
| 521 | for ( auto& assn : newAlt.need ) { |
---|
| 522 | // skip already-matched assertions |
---|
| 523 | if ( assn.info.resnSlot != 0 ) continue; |
---|
| 524 | // assign slot for expression if needed |
---|
| 525 | if ( crntResnSlot == 0 ) { crntResnSlot = ++globalResnSlot; } |
---|
| 526 | // fix slot to assertion |
---|
| 527 | assn.info.resnSlot = crntResnSlot; |
---|
| 528 | } |
---|
| 529 | // pair slot to expression |
---|
| 530 | if ( crntResnSlot != 0 ) { newAlt.expr->resnSlots.push_back( crntResnSlot ); } |
---|
| 531 | |
---|
| 532 | // add to output list, assertion resolution is deferred |
---|
[6d6e829] | 533 | *out++ = newAlt; |
---|
[d9a0e76] | 534 | } |
---|
| 535 | |
---|
[aeb75b1] | 536 | /// Gets a default value from an initializer, nullptr if not present |
---|
| 537 | ConstantExpr* getDefaultValue( Initializer* init ) { |
---|
| 538 | if ( SingleInit* si = dynamic_cast<SingleInit*>( init ) ) { |
---|
[630bcb5] | 539 | if ( CastExpr* ce = dynamic_cast<CastExpr*>( si->value ) ) { |
---|
| 540 | return dynamic_cast<ConstantExpr*>( ce->arg ); |
---|
| 541 | } else { |
---|
| 542 | return dynamic_cast<ConstantExpr*>( si->value ); |
---|
[aeb75b1] | 543 | } |
---|
| 544 | } |
---|
| 545 | return nullptr; |
---|
| 546 | } |
---|
| 547 | |
---|
| 548 | /// State to iteratively build a match of parameter expressions to arguments |
---|
| 549 | struct ArgPack { |
---|
[452747a] | 550 | std::size_t parent; ///< Index of parent pack |
---|
[403b388] | 551 | std::unique_ptr<Expression> expr; ///< The argument stored here |
---|
| 552 | Cost cost; ///< The cost of this argument |
---|
| 553 | TypeEnvironment env; ///< Environment for this pack |
---|
| 554 | AssertionSet need; ///< Assertions outstanding for this pack |
---|
| 555 | AssertionSet have; ///< Assertions found for this pack |
---|
| 556 | OpenVarSet openVars; ///< Open variables for this pack |
---|
| 557 | unsigned nextArg; ///< Index of next argument in arguments list |
---|
| 558 | unsigned tupleStart; ///< Number of tuples that start at this index |
---|
[a8b27c6] | 559 | unsigned nextExpl; ///< Index of next exploded element |
---|
| 560 | unsigned explAlt; ///< Index of alternative for nextExpl > 0 |
---|
[403b388] | 561 | |
---|
| 562 | ArgPack() |
---|
[ad51cc2] | 563 | : parent(0), expr(), cost(Cost::zero), env(), need(), have(), openVars(), nextArg(0), |
---|
[a8b27c6] | 564 | tupleStart(0), nextExpl(0), explAlt(0) {} |
---|
[aeb75b1] | 565 | |
---|
[11094d9] | 566 | ArgPack(const TypeEnvironment& env, const AssertionSet& need, const AssertionSet& have, |
---|
[aeb75b1] | 567 | const OpenVarSet& openVars) |
---|
[452747a] | 568 | : parent(0), expr(), cost(Cost::zero), env(env), need(need), have(have), |
---|
[a8b27c6] | 569 | openVars(openVars), nextArg(0), tupleStart(0), nextExpl(0), explAlt(0) {} |
---|
[11094d9] | 570 | |
---|
[452747a] | 571 | ArgPack(std::size_t parent, Expression* expr, TypeEnvironment&& env, AssertionSet&& need, |
---|
| 572 | AssertionSet&& have, OpenVarSet&& openVars, unsigned nextArg, |
---|
[178e4ec] | 573 | unsigned tupleStart = 0, Cost cost = Cost::zero, unsigned nextExpl = 0, |
---|
[a8b27c6] | 574 | unsigned explAlt = 0 ) |
---|
[452747a] | 575 | : parent(parent), expr(expr->clone()), cost(cost), env(move(env)), need(move(need)), |
---|
[403b388] | 576 | have(move(have)), openVars(move(openVars)), nextArg(nextArg), tupleStart(tupleStart), |
---|
[a8b27c6] | 577 | nextExpl(nextExpl), explAlt(explAlt) {} |
---|
[452747a] | 578 | |
---|
| 579 | ArgPack(const ArgPack& o, TypeEnvironment&& env, AssertionSet&& need, AssertionSet&& have, |
---|
[73a5cadb] | 580 | OpenVarSet&& openVars, unsigned nextArg, Cost added ) |
---|
[452747a] | 581 | : parent(o.parent), expr(o.expr ? o.expr->clone() : nullptr), cost(o.cost + added), |
---|
| 582 | env(move(env)), need(move(need)), have(move(have)), openVars(move(openVars)), |
---|
[a8b27c6] | 583 | nextArg(nextArg), tupleStart(o.tupleStart), nextExpl(0), explAlt(0) {} |
---|
[73a5cadb] | 584 | |
---|
[a8b27c6] | 585 | /// true iff this pack is in the middle of an exploded argument |
---|
| 586 | bool hasExpl() const { return nextExpl > 0; } |
---|
[aeb75b1] | 587 | |
---|
[a8b27c6] | 588 | /// Gets the list of exploded alternatives for this pack |
---|
[432ce7a] | 589 | const ExplodedActual& getExpl( const ExplodedArgs_old& args ) const { |
---|
[a8b27c6] | 590 | return args[nextArg-1][explAlt]; |
---|
| 591 | } |
---|
[aeb75b1] | 592 | |
---|
| 593 | /// Ends a tuple expression, consolidating the appropriate actuals |
---|
[403b388] | 594 | void endTuple( const std::vector<ArgPack>& packs ) { |
---|
| 595 | // add all expressions in tuple to list, summing cost |
---|
[aeb75b1] | 596 | std::list<Expression*> exprs; |
---|
[403b388] | 597 | const ArgPack* pack = this; |
---|
| 598 | if ( expr ) { exprs.push_front( expr.release() ); } |
---|
| 599 | while ( pack->tupleStart == 0 ) { |
---|
| 600 | pack = &packs[pack->parent]; |
---|
| 601 | exprs.push_front( pack->expr->clone() ); |
---|
| 602 | cost += pack->cost; |
---|
[aeb75b1] | 603 | } |
---|
[403b388] | 604 | // reset pack to appropriate tuple |
---|
| 605 | expr.reset( new TupleExpr( exprs ) ); |
---|
| 606 | tupleStart = pack->tupleStart - 1; |
---|
| 607 | parent = pack->parent; |
---|
[aeb75b1] | 608 | } |
---|
[4b6ef70] | 609 | }; |
---|
[aeb75b1] | 610 | |
---|
| 611 | /// Instantiates an argument to match a formal, returns false if no results left |
---|
[11094d9] | 612 | bool instantiateArgument( Type* formalType, Initializer* initializer, |
---|
[432ce7a] | 613 | const ExplodedArgs_old& args, std::vector<ArgPack>& results, std::size_t& genStart, |
---|
[a8b27c6] | 614 | const SymTab::Indexer& indexer, unsigned nTuples = 0 ) { |
---|
[3d2ae8d] | 615 | if ( TupleType * tupleType = dynamic_cast<TupleType*>( formalType ) ) { |
---|
[aeb75b1] | 616 | // formalType is a TupleType - group actuals into a TupleExpr |
---|
[403b388] | 617 | ++nTuples; |
---|
[aeb75b1] | 618 | for ( Type* type : *tupleType ) { |
---|
| 619 | // xxx - dropping initializer changes behaviour from previous, but seems correct |
---|
[3d2ae8d] | 620 | // ^^^ need to handle the case where a tuple has a default argument |
---|
[452747a] | 621 | if ( ! instantiateArgument( |
---|
| 622 | type, nullptr, args, results, genStart, indexer, nTuples ) ) |
---|
[aeb75b1] | 623 | return false; |
---|
[403b388] | 624 | nTuples = 0; |
---|
| 625 | } |
---|
| 626 | // re-consititute tuples for final generation |
---|
| 627 | for ( auto i = genStart; i < results.size(); ++i ) { |
---|
| 628 | results[i].endTuple( results ); |
---|
[aeb75b1] | 629 | } |
---|
| 630 | return true; |
---|
[3d2ae8d] | 631 | } else if ( TypeInstType * ttype = Tuples::isTtype( formalType ) ) { |
---|
[aeb75b1] | 632 | // formalType is a ttype, consumes all remaining arguments |
---|
| 633 | // xxx - mixing default arguments with variadic?? |
---|
[403b388] | 634 | |
---|
| 635 | // completed tuples; will be spliced to end of results to finish |
---|
| 636 | std::vector<ArgPack> finalResults{}; |
---|
| 637 | |
---|
[aeb75b1] | 638 | // iterate until all results completed |
---|
[403b388] | 639 | std::size_t genEnd; |
---|
| 640 | ++nTuples; |
---|
| 641 | do { |
---|
| 642 | genEnd = results.size(); |
---|
| 643 | |
---|
[aeb75b1] | 644 | // add another argument to results |
---|
[403b388] | 645 | for ( std::size_t i = genStart; i < genEnd; ++i ) { |
---|
[a8b27c6] | 646 | auto nextArg = results[i].nextArg; |
---|
[452747a] | 647 | |
---|
[62194cb] | 648 | // use next element of exploded tuple if present |
---|
[a8b27c6] | 649 | if ( results[i].hasExpl() ) { |
---|
| 650 | const ExplodedActual& expl = results[i].getExpl( args ); |
---|
[403b388] | 651 | |
---|
[a8b27c6] | 652 | unsigned nextExpl = results[i].nextExpl + 1; |
---|
[62194cb] | 653 | if ( nextExpl == expl.exprs.size() ) { |
---|
[a8b27c6] | 654 | nextExpl = 0; |
---|
| 655 | } |
---|
[403b388] | 656 | |
---|
| 657 | results.emplace_back( |
---|
[178e4ec] | 658 | i, expl.exprs[results[i].nextExpl].get(), copy(results[i].env), |
---|
| 659 | copy(results[i].need), copy(results[i].have), |
---|
| 660 | copy(results[i].openVars), nextArg, nTuples, Cost::zero, nextExpl, |
---|
[62194cb] | 661 | results[i].explAlt ); |
---|
[452747a] | 662 | |
---|
[403b388] | 663 | continue; |
---|
| 664 | } |
---|
[452747a] | 665 | |
---|
[aeb75b1] | 666 | // finish result when out of arguments |
---|
[a8b27c6] | 667 | if ( nextArg >= args.size() ) { |
---|
[452747a] | 668 | ArgPack newResult{ |
---|
| 669 | results[i].env, results[i].need, results[i].have, |
---|
[403b388] | 670 | results[i].openVars }; |
---|
[a8b27c6] | 671 | newResult.nextArg = nextArg; |
---|
[403b388] | 672 | Type* argType; |
---|
| 673 | |
---|
[7faab5e] | 674 | if ( nTuples > 0 || ! results[i].expr ) { |
---|
[ad51cc2] | 675 | // first iteration or no expression to clone, |
---|
[7faab5e] | 676 | // push empty tuple expression |
---|
[403b388] | 677 | newResult.parent = i; |
---|
| 678 | std::list<Expression*> emptyList; |
---|
| 679 | newResult.expr.reset( new TupleExpr( emptyList ) ); |
---|
| 680 | argType = newResult.expr->get_result(); |
---|
[aeb75b1] | 681 | } else { |
---|
[403b388] | 682 | // clone result to collect tuple |
---|
| 683 | newResult.parent = results[i].parent; |
---|
| 684 | newResult.cost = results[i].cost; |
---|
| 685 | newResult.tupleStart = results[i].tupleStart; |
---|
| 686 | newResult.expr.reset( results[i].expr->clone() ); |
---|
| 687 | argType = newResult.expr->get_result(); |
---|
| 688 | |
---|
| 689 | if ( results[i].tupleStart > 0 && Tuples::isTtype( argType ) ) { |
---|
[452747a] | 690 | // the case where a ttype value is passed directly is special, |
---|
[403b388] | 691 | // e.g. for argument forwarding purposes |
---|
[452747a] | 692 | // xxx - what if passing multiple arguments, last of which is |
---|
[403b388] | 693 | // ttype? |
---|
[452747a] | 694 | // xxx - what would happen if unify was changed so that unifying |
---|
| 695 | // tuple |
---|
| 696 | // types flattened both before unifying lists? then pass in |
---|
[403b388] | 697 | // TupleType (ttype) below. |
---|
| 698 | --newResult.tupleStart; |
---|
| 699 | } else { |
---|
| 700 | // collapse leftover arguments into tuple |
---|
| 701 | newResult.endTuple( results ); |
---|
| 702 | argType = newResult.expr->get_result(); |
---|
| 703 | } |
---|
[aeb75b1] | 704 | } |
---|
[403b388] | 705 | |
---|
[aeb75b1] | 706 | // check unification for ttype before adding to final |
---|
[452747a] | 707 | if ( unify( ttype, argType, newResult.env, newResult.need, newResult.have, |
---|
[403b388] | 708 | newResult.openVars, indexer ) ) { |
---|
| 709 | finalResults.push_back( move(newResult) ); |
---|
[aeb75b1] | 710 | } |
---|
[452747a] | 711 | |
---|
[aeb75b1] | 712 | continue; |
---|
| 713 | } |
---|
| 714 | |
---|
| 715 | // add each possible next argument |
---|
[a8b27c6] | 716 | for ( std::size_t j = 0; j < args[nextArg].size(); ++j ) { |
---|
| 717 | const ExplodedActual& expl = args[nextArg][j]; |
---|
[178e4ec] | 718 | |
---|
[403b388] | 719 | // fresh copies of parent parameters for this iteration |
---|
| 720 | TypeEnvironment env = results[i].env; |
---|
| 721 | OpenVarSet openVars = results[i].openVars; |
---|
| 722 | |
---|
[a8b27c6] | 723 | env.addActual( expl.env, openVars ); |
---|
[11094d9] | 724 | |
---|
[a8b27c6] | 725 | // skip empty tuple arguments by (near-)cloning parent into next gen |
---|
[62194cb] | 726 | if ( expl.exprs.empty() ) { |
---|
[73a5cadb] | 727 | results.emplace_back( |
---|
[452747a] | 728 | results[i], move(env), copy(results[i].need), |
---|
[a8b27c6] | 729 | copy(results[i].have), move(openVars), nextArg + 1, expl.cost ); |
---|
[452747a] | 730 | |
---|
[403b388] | 731 | continue; |
---|
[4b6ef70] | 732 | } |
---|
[11094d9] | 733 | |
---|
[403b388] | 734 | // add new result |
---|
| 735 | results.emplace_back( |
---|
[178e4ec] | 736 | i, expl.exprs.front().get(), move(env), copy(results[i].need), |
---|
| 737 | copy(results[i].have), move(openVars), nextArg + 1, |
---|
[62194cb] | 738 | nTuples, expl.cost, expl.exprs.size() == 1 ? 0 : 1, j ); |
---|
[aeb75b1] | 739 | } |
---|
| 740 | } |
---|
| 741 | |
---|
| 742 | // reset for next round |
---|
[403b388] | 743 | genStart = genEnd; |
---|
| 744 | nTuples = 0; |
---|
| 745 | } while ( genEnd != results.size() ); |
---|
| 746 | |
---|
| 747 | // splice final results onto results |
---|
| 748 | for ( std::size_t i = 0; i < finalResults.size(); ++i ) { |
---|
| 749 | results.push_back( move(finalResults[i]) ); |
---|
[aeb75b1] | 750 | } |
---|
[403b388] | 751 | return ! finalResults.empty(); |
---|
[aeb75b1] | 752 | } |
---|
[11094d9] | 753 | |
---|
[aeb75b1] | 754 | // iterate each current subresult |
---|
[403b388] | 755 | std::size_t genEnd = results.size(); |
---|
| 756 | for ( std::size_t i = genStart; i < genEnd; ++i ) { |
---|
[a8b27c6] | 757 | auto nextArg = results[i].nextArg; |
---|
| 758 | |
---|
[403b388] | 759 | // use remainder of exploded tuple if present |
---|
[a8b27c6] | 760 | if ( results[i].hasExpl() ) { |
---|
| 761 | const ExplodedActual& expl = results[i].getExpl( args ); |
---|
[62194cb] | 762 | Expression* expr = expl.exprs[results[i].nextExpl].get(); |
---|
[452747a] | 763 | |
---|
[403b388] | 764 | TypeEnvironment env = results[i].env; |
---|
| 765 | AssertionSet need = results[i].need, have = results[i].have; |
---|
| 766 | OpenVarSet openVars = results[i].openVars; |
---|
[4b6ef70] | 767 | |
---|
[62194cb] | 768 | Type* actualType = expr->get_result(); |
---|
[4b6ef70] | 769 | |
---|
| 770 | PRINT( |
---|
| 771 | std::cerr << "formal type is "; |
---|
| 772 | formalType->print( std::cerr ); |
---|
| 773 | std::cerr << std::endl << "actual type is "; |
---|
| 774 | actualType->print( std::cerr ); |
---|
| 775 | std::cerr << std::endl; |
---|
| 776 | ) |
---|
[11094d9] | 777 | |
---|
[403b388] | 778 | if ( unify( formalType, actualType, env, need, have, openVars, indexer ) ) { |
---|
[a8b27c6] | 779 | unsigned nextExpl = results[i].nextExpl + 1; |
---|
[62194cb] | 780 | if ( nextExpl == expl.exprs.size() ) { |
---|
[a8b27c6] | 781 | nextExpl = 0; |
---|
| 782 | } |
---|
[178e4ec] | 783 | |
---|
[452747a] | 784 | results.emplace_back( |
---|
[178e4ec] | 785 | i, expr, move(env), move(need), move(have), move(openVars), nextArg, |
---|
[62194cb] | 786 | nTuples, Cost::zero, nextExpl, results[i].explAlt ); |
---|
[4b6ef70] | 787 | } |
---|
| 788 | |
---|
| 789 | continue; |
---|
[403b388] | 790 | } |
---|
[452747a] | 791 | |
---|
[403b388] | 792 | // use default initializers if out of arguments |
---|
[a8b27c6] | 793 | if ( nextArg >= args.size() ) { |
---|
[aeb75b1] | 794 | if ( ConstantExpr* cnstExpr = getDefaultValue( initializer ) ) { |
---|
| 795 | if ( Constant* cnst = dynamic_cast<Constant*>( cnstExpr->get_constant() ) ) { |
---|
[403b388] | 796 | TypeEnvironment env = results[i].env; |
---|
| 797 | AssertionSet need = results[i].need, have = results[i].have; |
---|
| 798 | OpenVarSet openVars = results[i].openVars; |
---|
| 799 | |
---|
[452747a] | 800 | if ( unify( formalType, cnst->get_type(), env, need, have, openVars, |
---|
[403b388] | 801 | indexer ) ) { |
---|
| 802 | results.emplace_back( |
---|
[0f79853] | 803 | i, new DefaultArgExpr( cnstExpr ), move(env), move(need), move(have), |
---|
[a8b27c6] | 804 | move(openVars), nextArg, nTuples ); |
---|
[aeb75b1] | 805 | } |
---|
| 806 | } |
---|
| 807 | } |
---|
[403b388] | 808 | |
---|
[aeb75b1] | 809 | continue; |
---|
| 810 | } |
---|
| 811 | |
---|
| 812 | // Check each possible next argument |
---|
[a8b27c6] | 813 | for ( std::size_t j = 0; j < args[nextArg].size(); ++j ) { |
---|
| 814 | const ExplodedActual& expl = args[nextArg][j]; |
---|
| 815 | |
---|
[403b388] | 816 | // fresh copies of parent parameters for this iteration |
---|
| 817 | TypeEnvironment env = results[i].env; |
---|
| 818 | AssertionSet need = results[i].need, have = results[i].have; |
---|
| 819 | OpenVarSet openVars = results[i].openVars; |
---|
| 820 | |
---|
[a8b27c6] | 821 | env.addActual( expl.env, openVars ); |
---|
[4b6ef70] | 822 | |
---|
[a8b27c6] | 823 | // skip empty tuple arguments by (near-)cloning parent into next gen |
---|
[62194cb] | 824 | if ( expl.exprs.empty() ) { |
---|
[73a5cadb] | 825 | results.emplace_back( |
---|
[178e4ec] | 826 | results[i], move(env), move(need), move(have), move(openVars), |
---|
[a8b27c6] | 827 | nextArg + 1, expl.cost ); |
---|
[73a5cadb] | 828 | |
---|
[4b6ef70] | 829 | continue; |
---|
| 830 | } |
---|
[aeb75b1] | 831 | |
---|
[4b6ef70] | 832 | // consider only first exploded actual |
---|
[62194cb] | 833 | Expression* expr = expl.exprs.front().get(); |
---|
[3d2ae8d] | 834 | Type* actualType = expr->result->clone(); |
---|
[a585396] | 835 | |
---|
[4b6ef70] | 836 | PRINT( |
---|
| 837 | std::cerr << "formal type is "; |
---|
| 838 | formalType->print( std::cerr ); |
---|
| 839 | std::cerr << std::endl << "actual type is "; |
---|
| 840 | actualType->print( std::cerr ); |
---|
| 841 | std::cerr << std::endl; |
---|
| 842 | ) |
---|
[aeb75b1] | 843 | |
---|
[4b6ef70] | 844 | // attempt to unify types |
---|
[403b388] | 845 | if ( unify( formalType, actualType, env, need, have, openVars, indexer ) ) { |
---|
| 846 | // add new result |
---|
| 847 | results.emplace_back( |
---|
[178e4ec] | 848 | i, expr, move(env), move(need), move(have), move(openVars), nextArg + 1, |
---|
[62194cb] | 849 | nTuples, expl.cost, expl.exprs.size() == 1 ? 0 : 1, j ); |
---|
[4b6ef70] | 850 | } |
---|
[aeb75b1] | 851 | } |
---|
| 852 | } |
---|
| 853 | |
---|
| 854 | // reset for next parameter |
---|
[403b388] | 855 | genStart = genEnd; |
---|
[11094d9] | 856 | |
---|
[403b388] | 857 | return genEnd != results.size(); |
---|
| 858 | } |
---|
| 859 | |
---|
| 860 | template<typename OutputIterator> |
---|
[13deae88] | 861 | void AlternativeFinder::Finder::validateFunctionAlternative( const Alternative &func, ArgPack& result, |
---|
[403b388] | 862 | const std::vector<ArgPack>& results, OutputIterator out ) { |
---|
| 863 | ApplicationExpr *appExpr = new ApplicationExpr( func.expr->clone() ); |
---|
| 864 | // sum cost and accumulate actuals |
---|
[3d2ae8d] | 865 | std::list<Expression*>& args = appExpr->args; |
---|
[8a62d04] | 866 | Cost cost = func.cost; |
---|
[403b388] | 867 | const ArgPack* pack = &result; |
---|
| 868 | while ( pack->expr ) { |
---|
| 869 | args.push_front( pack->expr->clone() ); |
---|
| 870 | cost += pack->cost; |
---|
| 871 | pack = &results[pack->parent]; |
---|
| 872 | } |
---|
| 873 | // build and validate new alternative |
---|
[2c187378] | 874 | Alternative newAlt{ appExpr, result.env, result.openVars, result.need, cost }; |
---|
[403b388] | 875 | PRINT( |
---|
| 876 | std::cerr << "instantiate function success: " << appExpr << std::endl; |
---|
| 877 | std::cerr << "need assertions:" << std::endl; |
---|
| 878 | printAssertionSet( result.need, std::cerr, 8 ); |
---|
| 879 | ) |
---|
[0b00df0] | 880 | inferParameters( newAlt, out ); |
---|
[11094d9] | 881 | } |
---|
[aeb75b1] | 882 | |
---|
| 883 | template<typename OutputIterator> |
---|
[13deae88] | 884 | void AlternativeFinder::Finder::makeFunctionAlternatives( const Alternative &func, |
---|
[432ce7a] | 885 | FunctionType *funcType, const ExplodedArgs_old &args, OutputIterator out ) { |
---|
[aeb75b1] | 886 | OpenVarSet funcOpenVars; |
---|
| 887 | AssertionSet funcNeed, funcHave; |
---|
[3f7e12cb] | 888 | TypeEnvironment funcEnv( func.env ); |
---|
[aeb75b1] | 889 | makeUnifiableVars( funcType, funcOpenVars, funcNeed ); |
---|
[11094d9] | 890 | // add all type variables as open variables now so that those not used in the parameter |
---|
[aeb75b1] | 891 | // list are still considered open. |
---|
[3d2ae8d] | 892 | funcEnv.add( funcType->forall ); |
---|
[11094d9] | 893 | |
---|
[3d2ae8d] | 894 | if ( targetType && ! targetType->isVoid() && ! funcType->returnVals.empty() ) { |
---|
[ea83e00a] | 895 | // attempt to narrow based on expected target type |
---|
[3d2ae8d] | 896 | Type * returnType = funcType->returnVals.front()->get_type(); |
---|
[11094d9] | 897 | if ( ! unify( returnType, targetType, funcEnv, funcNeed, funcHave, funcOpenVars, |
---|
[aeb75b1] | 898 | indexer ) ) { |
---|
| 899 | // unification failed, don't pursue this function alternative |
---|
[ea83e00a] | 900 | return; |
---|
| 901 | } |
---|
| 902 | } |
---|
| 903 | |
---|
[aeb75b1] | 904 | // iteratively build matches, one parameter at a time |
---|
[403b388] | 905 | std::vector<ArgPack> results; |
---|
| 906 | results.push_back( ArgPack{ funcEnv, funcNeed, funcHave, funcOpenVars } ); |
---|
| 907 | std::size_t genStart = 0; |
---|
| 908 | |
---|
[3d2ae8d] | 909 | for ( DeclarationWithType* formal : funcType->parameters ) { |
---|
[aeb75b1] | 910 | ObjectDecl* obj = strict_dynamic_cast< ObjectDecl* >( formal ); |
---|
[11094d9] | 911 | if ( ! instantiateArgument( |
---|
[3d2ae8d] | 912 | obj->type, obj->init, args, results, genStart, indexer ) ) |
---|
[aeb75b1] | 913 | return; |
---|
| 914 | } |
---|
| 915 | |
---|
| 916 | if ( funcType->get_isVarArgs() ) { |
---|
[403b388] | 917 | // append any unused arguments to vararg pack |
---|
| 918 | std::size_t genEnd; |
---|
| 919 | do { |
---|
| 920 | genEnd = results.size(); |
---|
| 921 | |
---|
| 922 | // iterate results |
---|
| 923 | for ( std::size_t i = genStart; i < genEnd; ++i ) { |
---|
[a8b27c6] | 924 | auto nextArg = results[i].nextArg; |
---|
[452747a] | 925 | |
---|
[403b388] | 926 | // use remainder of exploded tuple if present |
---|
[a8b27c6] | 927 | if ( results[i].hasExpl() ) { |
---|
| 928 | const ExplodedActual& expl = results[i].getExpl( args ); |
---|
[403b388] | 929 | |
---|
[a8b27c6] | 930 | unsigned nextExpl = results[i].nextExpl + 1; |
---|
[62194cb] | 931 | if ( nextExpl == expl.exprs.size() ) { |
---|
[a8b27c6] | 932 | nextExpl = 0; |
---|
| 933 | } |
---|
[403b388] | 934 | |
---|
| 935 | results.emplace_back( |
---|
[178e4ec] | 936 | i, expl.exprs[results[i].nextExpl].get(), copy(results[i].env), |
---|
| 937 | copy(results[i].need), copy(results[i].have), |
---|
| 938 | copy(results[i].openVars), nextArg, 0, Cost::zero, nextExpl, |
---|
[62194cb] | 939 | results[i].explAlt ); |
---|
[452747a] | 940 | |
---|
[403b388] | 941 | continue; |
---|
| 942 | } |
---|
| 943 | |
---|
| 944 | // finish result when out of arguments |
---|
[a8b27c6] | 945 | if ( nextArg >= args.size() ) { |
---|
[403b388] | 946 | validateFunctionAlternative( func, results[i], results, out ); |
---|
[fae6f21] | 947 | |
---|
[aeb75b1] | 948 | continue; |
---|
| 949 | } |
---|
| 950 | |
---|
| 951 | // add each possible next argument |
---|
[a8b27c6] | 952 | for ( std::size_t j = 0; j < args[nextArg].size(); ++j ) { |
---|
| 953 | const ExplodedActual& expl = args[nextArg][j]; |
---|
| 954 | |
---|
[403b388] | 955 | // fresh copies of parent parameters for this iteration |
---|
| 956 | TypeEnvironment env = results[i].env; |
---|
| 957 | OpenVarSet openVars = results[i].openVars; |
---|
| 958 | |
---|
[a8b27c6] | 959 | env.addActual( expl.env, openVars ); |
---|
[d551d0a] | 960 | |
---|
[a8b27c6] | 961 | // skip empty tuple arguments by (near-)cloning parent into next gen |
---|
[62194cb] | 962 | if ( expl.exprs.empty() ) { |
---|
[452747a] | 963 | results.emplace_back( |
---|
| 964 | results[i], move(env), copy(results[i].need), |
---|
[a8b27c6] | 965 | copy(results[i].have), move(openVars), nextArg + 1, expl.cost ); |
---|
[178e4ec] | 966 | |
---|
[403b388] | 967 | continue; |
---|
| 968 | } |
---|
[d551d0a] | 969 | |
---|
[403b388] | 970 | // add new result |
---|
| 971 | results.emplace_back( |
---|
[178e4ec] | 972 | i, expl.exprs.front().get(), move(env), copy(results[i].need), |
---|
| 973 | copy(results[i].have), move(openVars), nextArg + 1, 0, |
---|
[62194cb] | 974 | expl.cost, expl.exprs.size() == 1 ? 0 : 1, j ); |
---|
[aeb75b1] | 975 | } |
---|
| 976 | } |
---|
| 977 | |
---|
[403b388] | 978 | genStart = genEnd; |
---|
| 979 | } while ( genEnd != results.size() ); |
---|
[aeb75b1] | 980 | } else { |
---|
| 981 | // filter out results that don't use all the arguments |
---|
[403b388] | 982 | for ( std::size_t i = genStart; i < results.size(); ++i ) { |
---|
| 983 | ArgPack& result = results[i]; |
---|
[a8b27c6] | 984 | if ( ! result.hasExpl() && result.nextArg >= args.size() ) { |
---|
[403b388] | 985 | validateFunctionAlternative( func, result, results, out ); |
---|
[aeb75b1] | 986 | } |
---|
| 987 | } |
---|
| 988 | } |
---|
[d9a0e76] | 989 | } |
---|
| 990 | |
---|
[13deae88] | 991 | void AlternativeFinder::Finder::postvisit( UntypedExpr *untypedExpr ) { |
---|
[6ccfb7f] | 992 | AlternativeFinder funcFinder( indexer, env ); |
---|
[3d2ae8d] | 993 | funcFinder.findWithAdjustment( untypedExpr->function ); |
---|
[6ccfb7f] | 994 | // if there are no function alternatives, then proceeding is a waste of time. |
---|
[630bcb5] | 995 | // xxx - findWithAdjustment throws, so this check and others like it shouldn't be necessary. |
---|
[6ccfb7f] | 996 | if ( funcFinder.alternatives.empty() ) return; |
---|
| 997 | |
---|
[aeb75b1] | 998 | std::vector< AlternativeFinder > argAlternatives; |
---|
[13deae88] | 999 | altFinder.findSubExprs( untypedExpr->begin_args(), untypedExpr->end_args(), |
---|
[aeb75b1] | 1000 | back_inserter( argAlternatives ) ); |
---|
[d9a0e76] | 1001 | |
---|
[5af62f1] | 1002 | // take care of possible tuple assignments |
---|
| 1003 | // if not tuple assignment, assignment is taken care of as a normal function call |
---|
[13deae88] | 1004 | Tuples::handleTupleAssignment( altFinder, untypedExpr, argAlternatives ); |
---|
[c43c171] | 1005 | |
---|
[6ccfb7f] | 1006 | // find function operators |
---|
[4e66a18] | 1007 | static NameExpr *opExpr = new NameExpr( "?()" ); |
---|
[6ccfb7f] | 1008 | AlternativeFinder funcOpFinder( indexer, env ); |
---|
[4e66a18] | 1009 | // it's ok if there aren't any defined function ops |
---|
[00ac42e] | 1010 | funcOpFinder.maybeFind( opExpr ); |
---|
[6ccfb7f] | 1011 | PRINT( |
---|
| 1012 | std::cerr << "known function ops:" << std::endl; |
---|
[50377a4] | 1013 | printAlts( funcOpFinder.alternatives, std::cerr, 1 ); |
---|
[6ccfb7f] | 1014 | ) |
---|
| 1015 | |
---|
[a8b27c6] | 1016 | // pre-explode arguments |
---|
[432ce7a] | 1017 | ExplodedArgs_old argExpansions; |
---|
[a8b27c6] | 1018 | argExpansions.reserve( argAlternatives.size() ); |
---|
| 1019 | |
---|
| 1020 | for ( const AlternativeFinder& arg : argAlternatives ) { |
---|
| 1021 | argExpansions.emplace_back(); |
---|
| 1022 | auto& argE = argExpansions.back(); |
---|
[d286cf68] | 1023 | // argE.reserve( arg.alternatives.size() ); |
---|
[178e4ec] | 1024 | |
---|
[a8b27c6] | 1025 | for ( const Alternative& actual : arg ) { |
---|
| 1026 | argE.emplace_back( actual, indexer ); |
---|
| 1027 | } |
---|
| 1028 | } |
---|
| 1029 | |
---|
[a32b204] | 1030 | AltList candidates; |
---|
[a16764a6] | 1031 | SemanticErrorException errors; |
---|
[b1bead1] | 1032 | for ( AltList::iterator func = funcFinder.alternatives.begin(); func != funcFinder.alternatives.end(); ++func ) { |
---|
[91b8a17] | 1033 | try { |
---|
| 1034 | PRINT( |
---|
| 1035 | std::cerr << "working on alternative: " << std::endl; |
---|
| 1036 | func->print( std::cerr, 8 ); |
---|
| 1037 | ) |
---|
| 1038 | // check if the type is pointer to function |
---|
[3d2ae8d] | 1039 | if ( PointerType *pointer = dynamic_cast< PointerType* >( func->expr->result->stripReferences() ) ) { |
---|
| 1040 | if ( FunctionType *function = dynamic_cast< FunctionType* >( pointer->base ) ) { |
---|
[326338ae] | 1041 | Alternative newFunc( *func ); |
---|
[a181494] | 1042 | referenceToRvalueConversion( newFunc.expr, newFunc.cost ); |
---|
[a8b27c6] | 1043 | makeFunctionAlternatives( newFunc, function, argExpansions, |
---|
[aeb75b1] | 1044 | std::back_inserter( candidates ) ); |
---|
[b1bead1] | 1045 | } |
---|
[3d2ae8d] | 1046 | } else if ( TypeInstType *typeInst = dynamic_cast< TypeInstType* >( func->expr->result->stripReferences() ) ) { // handle ftype (e.g. *? on function pointer) |
---|
[00ac42e] | 1047 | if ( const EqvClass *eqvClass = func->env.lookup( typeInst->name ) ) { |
---|
| 1048 | if ( FunctionType *function = dynamic_cast< FunctionType* >( eqvClass->type ) ) { |
---|
[326338ae] | 1049 | Alternative newFunc( *func ); |
---|
[a181494] | 1050 | referenceToRvalueConversion( newFunc.expr, newFunc.cost ); |
---|
[a8b27c6] | 1051 | makeFunctionAlternatives( newFunc, function, argExpansions, |
---|
[aeb75b1] | 1052 | std::back_inserter( candidates ) ); |
---|
[a32b204] | 1053 | } // if |
---|
| 1054 | } // if |
---|
[11094d9] | 1055 | } |
---|
[a16764a6] | 1056 | } catch ( SemanticErrorException &e ) { |
---|
[91b8a17] | 1057 | errors.append( e ); |
---|
| 1058 | } |
---|
[a32b204] | 1059 | } // for |
---|
| 1060 | |
---|
[aeb75b1] | 1061 | // try each function operator ?() with each function alternative |
---|
| 1062 | if ( ! funcOpFinder.alternatives.empty() ) { |
---|
[a8b27c6] | 1063 | // add exploded function alternatives to front of argument list |
---|
| 1064 | std::vector<ExplodedActual> funcE; |
---|
| 1065 | funcE.reserve( funcFinder.alternatives.size() ); |
---|
| 1066 | for ( const Alternative& actual : funcFinder ) { |
---|
| 1067 | funcE.emplace_back( actual, indexer ); |
---|
| 1068 | } |
---|
| 1069 | argExpansions.insert( argExpansions.begin(), move(funcE) ); |
---|
[aeb75b1] | 1070 | |
---|
| 1071 | for ( AltList::iterator funcOp = funcOpFinder.alternatives.begin(); |
---|
| 1072 | funcOp != funcOpFinder.alternatives.end(); ++funcOp ) { |
---|
| 1073 | try { |
---|
| 1074 | // check if type is a pointer to function |
---|
[11094d9] | 1075 | if ( PointerType* pointer = dynamic_cast<PointerType*>( |
---|
[3d2ae8d] | 1076 | funcOp->expr->result->stripReferences() ) ) { |
---|
[11094d9] | 1077 | if ( FunctionType* function = |
---|
[3d2ae8d] | 1078 | dynamic_cast<FunctionType*>( pointer->base ) ) { |
---|
[aeb75b1] | 1079 | Alternative newFunc( *funcOp ); |
---|
[a181494] | 1080 | referenceToRvalueConversion( newFunc.expr, newFunc.cost ); |
---|
[a8b27c6] | 1081 | makeFunctionAlternatives( newFunc, function, argExpansions, |
---|
[aeb75b1] | 1082 | std::back_inserter( candidates ) ); |
---|
| 1083 | } |
---|
| 1084 | } |
---|
[a16764a6] | 1085 | } catch ( SemanticErrorException &e ) { |
---|
[aeb75b1] | 1086 | errors.append( e ); |
---|
| 1087 | } |
---|
| 1088 | } |
---|
| 1089 | } |
---|
| 1090 | |
---|
[91b8a17] | 1091 | // Implement SFINAE; resolution errors are only errors if there aren't any non-erroneous resolutions |
---|
| 1092 | if ( candidates.empty() && ! errors.isEmpty() ) { throw errors; } |
---|
| 1093 | |
---|
[4b0f997] | 1094 | // compute conversionsion costs |
---|
[bd4f2e9] | 1095 | for ( Alternative& withFunc : candidates ) { |
---|
| 1096 | Cost cvtCost = computeApplicationConversionCost( withFunc, indexer ); |
---|
[a32b204] | 1097 | |
---|
| 1098 | PRINT( |
---|
[bd4f2e9] | 1099 | ApplicationExpr *appExpr = strict_dynamic_cast< ApplicationExpr* >( withFunc.expr ); |
---|
[3d2ae8d] | 1100 | PointerType *pointer = strict_dynamic_cast< PointerType* >( appExpr->function->result ); |
---|
| 1101 | FunctionType *function = strict_dynamic_cast< FunctionType* >( pointer->base ); |
---|
| 1102 | std::cerr << "Case +++++++++++++ " << appExpr->function << std::endl; |
---|
[6ed1d4b] | 1103 | std::cerr << "formals are:" << std::endl; |
---|
[3d2ae8d] | 1104 | printAll( function->parameters, std::cerr, 8 ); |
---|
[6ed1d4b] | 1105 | std::cerr << "actuals are:" << std::endl; |
---|
[3d2ae8d] | 1106 | printAll( appExpr->args, std::cerr, 8 ); |
---|
[6ed1d4b] | 1107 | std::cerr << "bindings are:" << std::endl; |
---|
[bd4f2e9] | 1108 | withFunc.env.print( std::cerr, 8 ); |
---|
[04cccaf] | 1109 | std::cerr << "cost is: " << withFunc.cost << std::endl; |
---|
[6ed1d4b] | 1110 | std::cerr << "cost of conversion is:" << cvtCost << std::endl; |
---|
[7c64920] | 1111 | ) |
---|
| 1112 | if ( cvtCost != Cost::infinity ) { |
---|
[bd4f2e9] | 1113 | withFunc.cvtCost = cvtCost; |
---|
| 1114 | alternatives.push_back( withFunc ); |
---|
[7c64920] | 1115 | } // if |
---|
[a32b204] | 1116 | } // for |
---|
[4b0f997] | 1117 | |
---|
[bd4f2e9] | 1118 | candidates = move(alternatives); |
---|
[a32b204] | 1119 | |
---|
[11094d9] | 1120 | // use a new list so that alternatives are not examined by addAnonConversions twice. |
---|
| 1121 | AltList winners; |
---|
| 1122 | findMinCost( candidates.begin(), candidates.end(), std::back_inserter( winners ) ); |
---|
[ea83e00a] | 1123 | |
---|
[452747a] | 1124 | // function may return struct or union value, in which case we need to add alternatives |
---|
[73ac10e] | 1125 | // for implicit conversions to each of the anonymous members, must happen after findMinCost |
---|
[bd4f2e9] | 1126 | // since anon conversions are never the cheapest expression |
---|
[11094d9] | 1127 | for ( const Alternative & alt : winners ) { |
---|
[ca946a4] | 1128 | addAnonConversions( alt ); |
---|
| 1129 | } |
---|
[bd4f2e9] | 1130 | spliceBegin( alternatives, winners ); |
---|
[ca946a4] | 1131 | |
---|
[ea83e00a] | 1132 | if ( alternatives.empty() && targetType && ! targetType->isVoid() ) { |
---|
| 1133 | // xxx - this is a temporary hack. If resolution is unsuccessful with a target type, try again without a |
---|
| 1134 | // target type, since it will sometimes succeed when it wouldn't easily with target type binding. For example, |
---|
| 1135 | // forall( otype T ) lvalue T ?[?]( T *, ptrdiff_t ); |
---|
| 1136 | // const char * x = "hello world"; |
---|
| 1137 | // unsigned char ch = x[0]; |
---|
| 1138 | // Fails with simple return type binding. First, T is bound to unsigned char, then (x: const char *) is unified |
---|
| 1139 | // with unsigned char *, which fails because pointer base types must be unified exactly. The new resolver should |
---|
| 1140 | // fix this issue in a more robust way. |
---|
| 1141 | targetType = nullptr; |
---|
[13deae88] | 1142 | postvisit( untypedExpr ); |
---|
[ea83e00a] | 1143 | } |
---|
[a32b204] | 1144 | } |
---|
| 1145 | |
---|
| 1146 | bool isLvalue( Expression *expr ) { |
---|
[906e24d] | 1147 | // xxx - recurse into tuples? |
---|
[2d80111] | 1148 | return expr->result && ( expr->get_lvalue() || dynamic_cast< ReferenceType * >( expr->result ) ); |
---|
[a32b204] | 1149 | } |
---|
| 1150 | |
---|
[13deae88] | 1151 | void AlternativeFinder::Finder::postvisit( AddressExpr *addressExpr ) { |
---|
[a32b204] | 1152 | AlternativeFinder finder( indexer, env ); |
---|
| 1153 | finder.find( addressExpr->get_arg() ); |
---|
[bd4f2e9] | 1154 | for ( Alternative& alt : finder.alternatives ) { |
---|
| 1155 | if ( isLvalue( alt.expr ) ) { |
---|
[452747a] | 1156 | alternatives.push_back( |
---|
[6d6e829] | 1157 | Alternative{ alt, new AddressExpr( alt.expr->clone() ), alt.cost } ); |
---|
[a32b204] | 1158 | } // if |
---|
| 1159 | } // for |
---|
| 1160 | } |
---|
| 1161 | |
---|
[13deae88] | 1162 | void AlternativeFinder::Finder::postvisit( LabelAddressExpr * expr ) { |
---|
[6d6e829] | 1163 | alternatives.push_back( Alternative{ expr->clone(), env } ); |
---|
[5809461] | 1164 | } |
---|
| 1165 | |
---|
[c0bf94e] | 1166 | Expression * restructureCast( Expression * argExpr, Type * toType, bool isGenerated ) { |
---|
[e6cee92] | 1167 | if ( argExpr->get_result()->size() > 1 && ! toType->isVoid() && ! dynamic_cast<ReferenceType *>( toType ) ) { |
---|
| 1168 | // Argument expression is a tuple and the target type is not void and not a reference type. |
---|
| 1169 | // Cast each member of the tuple to its corresponding target type, producing the tuple of those |
---|
| 1170 | // cast expressions. If there are more components of the tuple than components in the target type, |
---|
| 1171 | // then excess components do not come out in the result expression (but UniqueExprs ensure that |
---|
| 1172 | // side effects will still be done). |
---|
[5ccb10d] | 1173 | if ( Tuples::maybeImpureIgnoreUnique( argExpr ) ) { |
---|
[62423350] | 1174 | // expressions which may contain side effects require a single unique instance of the expression. |
---|
| 1175 | argExpr = new UniqueExpr( argExpr ); |
---|
| 1176 | } |
---|
| 1177 | std::list< Expression * > componentExprs; |
---|
| 1178 | for ( unsigned int i = 0; i < toType->size(); i++ ) { |
---|
| 1179 | // cast each component |
---|
| 1180 | TupleIndexExpr * idx = new TupleIndexExpr( argExpr->clone(), i ); |
---|
[c0bf94e] | 1181 | componentExprs.push_back( restructureCast( idx, toType->getComponent( i ), isGenerated ) ); |
---|
[62423350] | 1182 | } |
---|
| 1183 | delete argExpr; |
---|
| 1184 | assert( componentExprs.size() > 0 ); |
---|
| 1185 | // produce the tuple of casts |
---|
| 1186 | return new TupleExpr( componentExprs ); |
---|
| 1187 | } else { |
---|
| 1188 | // handle normally |
---|
[c0bf94e] | 1189 | CastExpr * ret = new CastExpr( argExpr, toType->clone() ); |
---|
| 1190 | ret->isGenerated = isGenerated; |
---|
| 1191 | return ret; |
---|
[62423350] | 1192 | } |
---|
| 1193 | } |
---|
| 1194 | |
---|
[13deae88] | 1195 | void AlternativeFinder::Finder::postvisit( CastExpr *castExpr ) { |
---|
[906e24d] | 1196 | Type *& toType = castExpr->get_result(); |
---|
[7933351] | 1197 | assert( toType ); |
---|
[906e24d] | 1198 | toType = resolveTypeof( toType, indexer ); |
---|
[cc4218f] | 1199 | assert(!dynamic_cast<TypeofType *>(toType)); |
---|
[906e24d] | 1200 | SymTab::validateType( toType, &indexer ); |
---|
| 1201 | adjustExprType( toType, env, indexer ); |
---|
[a32b204] | 1202 | |
---|
| 1203 | AlternativeFinder finder( indexer, env ); |
---|
[7933351] | 1204 | finder.targetType = toType; |
---|
[95642c9] | 1205 | finder.findWithAdjustment( castExpr->arg ); |
---|
[a32b204] | 1206 | |
---|
| 1207 | AltList candidates; |
---|
[452747a] | 1208 | for ( Alternative & alt : finder.alternatives ) { |
---|
[6d6e829] | 1209 | AssertionSet needAssertions( alt.need.begin(), alt.need.end() ); |
---|
| 1210 | AssertionSet haveAssertions; |
---|
| 1211 | OpenVarSet openVars{ alt.openVars }; |
---|
[a32b204] | 1212 | |
---|
[a8706fc] | 1213 | alt.env.extractOpenVars( openVars ); |
---|
| 1214 | |
---|
[a32b204] | 1215 | // It's possible that a cast can throw away some values in a multiply-valued expression. (An example is a |
---|
| 1216 | // cast-to-void, which casts from one value to zero.) Figure out the prefix of the subexpression results |
---|
| 1217 | // that are cast directly. The candidate is invalid if it has fewer results than there are types to cast |
---|
| 1218 | // to. |
---|
[95642c9] | 1219 | int discardedValues = alt.expr->result->size() - castExpr->result->size(); |
---|
[a32b204] | 1220 | if ( discardedValues < 0 ) continue; |
---|
[7933351] | 1221 | // xxx - may need to go into tuple types and extract relevant types and use unifyList. Note that currently, this does not |
---|
| 1222 | // allow casting a tuple to an atomic type (e.g. (int)([1, 2, 3])) |
---|
[adcdd2f] | 1223 | // unification run for side-effects |
---|
[95642c9] | 1224 | unify( castExpr->result, alt.expr->result, alt.env, needAssertions, |
---|
[bd4f2e9] | 1225 | haveAssertions, openVars, indexer ); |
---|
[b81fd95] | 1226 | Cost thisCost = |
---|
| 1227 | castExpr->isGenerated |
---|
| 1228 | ? conversionCost( alt.expr->result, castExpr->result, alt.expr->get_lvalue(), indexer, alt.env ) |
---|
| 1229 | : castCost( alt.expr->result, castExpr->result, alt.expr->get_lvalue(), indexer, alt.env ); |
---|
[7e4c4f4] | 1230 | PRINT( |
---|
| 1231 | std::cerr << "working on cast with result: " << castExpr->result << std::endl; |
---|
[452747a] | 1232 | std::cerr << "and expr type: " << alt.expr->result << std::endl; |
---|
| 1233 | std::cerr << "env: " << alt.env << std::endl; |
---|
[7e4c4f4] | 1234 | ) |
---|
[a32b204] | 1235 | if ( thisCost != Cost::infinity ) { |
---|
[7e4c4f4] | 1236 | PRINT( |
---|
| 1237 | std::cerr << "has finite cost." << std::endl; |
---|
| 1238 | ) |
---|
[a32b204] | 1239 | // count one safe conversion for each value that is thrown away |
---|
[89be1c68] | 1240 | thisCost.incSafe( discardedValues ); |
---|
[6f096d2] | 1241 | Alternative newAlt{ |
---|
| 1242 | restructureCast( alt.expr->clone(), toType, castExpr->isGenerated ), |
---|
[bd78797] | 1243 | alt.env, openVars, needAssertions, alt.cost, alt.cost + thisCost }; |
---|
[0b00df0] | 1244 | inferParameters( newAlt, back_inserter( candidates ) ); |
---|
[a32b204] | 1245 | } // if |
---|
| 1246 | } // for |
---|
| 1247 | |
---|
| 1248 | // findMinCost selects the alternatives with the lowest "cost" members, but has the side effect of copying the |
---|
| 1249 | // cvtCost member to the cost member (since the old cost is now irrelevant). Thus, calling findMinCost twice |
---|
| 1250 | // selects first based on argument cost, then on conversion cost. |
---|
| 1251 | AltList minArgCost; |
---|
| 1252 | findMinCost( candidates.begin(), candidates.end(), std::back_inserter( minArgCost ) ); |
---|
| 1253 | findMinCost( minArgCost.begin(), minArgCost.end(), std::back_inserter( alternatives ) ); |
---|
| 1254 | } |
---|
| 1255 | |
---|
[13deae88] | 1256 | void AlternativeFinder::Finder::postvisit( VirtualCastExpr * castExpr ) { |
---|
[6d6e829] | 1257 | assertf( castExpr->get_result(), "Implicit virtual cast targets not yet supported." ); |
---|
[a5f0529] | 1258 | AlternativeFinder finder( indexer, env ); |
---|
| 1259 | // don't prune here, since it's guaranteed all alternatives will have the same type |
---|
[4e66a18] | 1260 | finder.findWithoutPrune( castExpr->get_arg() ); |
---|
[a5f0529] | 1261 | for ( Alternative & alt : finder.alternatives ) { |
---|
[6d6e829] | 1262 | alternatives.push_back( Alternative{ |
---|
| 1263 | alt, new VirtualCastExpr{ alt.expr->clone(), castExpr->get_result()->clone() }, |
---|
| 1264 | alt.cost } ); |
---|
[a5f0529] | 1265 | } |
---|
| 1266 | } |
---|
| 1267 | |
---|
[3b0c8cb] | 1268 | void AlternativeFinder::Finder::postvisit( KeywordCastExpr * castExpr ) { |
---|
| 1269 | assertf( castExpr->get_result(), "Cast target should have been set in Validate." ); |
---|
| 1270 | auto ref = dynamic_cast<ReferenceType*>(castExpr->get_result()); |
---|
| 1271 | assert(ref); |
---|
| 1272 | auto inst = dynamic_cast<StructInstType*>(ref->base); |
---|
| 1273 | assert(inst); |
---|
| 1274 | auto target = inst->baseStruct; |
---|
| 1275 | |
---|
| 1276 | AlternativeFinder finder( indexer, env ); |
---|
| 1277 | |
---|
| 1278 | auto pick_alternatives = [target, this](AltList & found, bool expect_ref) { |
---|
| 1279 | for(auto & alt : found) { |
---|
| 1280 | Type * expr = alt.expr->get_result(); |
---|
| 1281 | if(expect_ref) { |
---|
| 1282 | auto res = dynamic_cast<ReferenceType*>(expr); |
---|
| 1283 | if(!res) { continue; } |
---|
| 1284 | expr = res->base; |
---|
| 1285 | } |
---|
| 1286 | |
---|
| 1287 | if(auto insttype = dynamic_cast<TypeInstType*>(expr)) { |
---|
| 1288 | auto td = alt.env.lookup(insttype->name); |
---|
| 1289 | if(!td) { continue; } |
---|
| 1290 | expr = td->type; |
---|
| 1291 | } |
---|
| 1292 | |
---|
| 1293 | if(auto base = dynamic_cast<StructInstType*>(expr)) { |
---|
| 1294 | if(base->baseStruct == target) { |
---|
| 1295 | alternatives.push_back( |
---|
| 1296 | std::move(alt) |
---|
| 1297 | ); |
---|
| 1298 | } |
---|
| 1299 | } |
---|
| 1300 | } |
---|
| 1301 | }; |
---|
| 1302 | |
---|
| 1303 | try { |
---|
[7f62b708] | 1304 | // Attempt 1 : turn (thread&)X into (thread$&)X.__thrd |
---|
[3b0c8cb] | 1305 | // Clone is purely for memory management |
---|
| 1306 | std::unique_ptr<Expression> tech1 { new UntypedMemberExpr(new NameExpr(castExpr->concrete_target.field), castExpr->arg->clone()) }; |
---|
| 1307 | |
---|
| 1308 | // don't prune here, since it's guaranteed all alternatives will have the same type |
---|
| 1309 | finder.findWithoutPrune( tech1.get() ); |
---|
| 1310 | pick_alternatives(finder.alternatives, false); |
---|
| 1311 | |
---|
| 1312 | return; |
---|
| 1313 | } catch(SemanticErrorException & ) {} |
---|
| 1314 | |
---|
[7f62b708] | 1315 | // Fallback : turn (thread&)X into (thread$&)get_thread(X) |
---|
[3b0c8cb] | 1316 | std::unique_ptr<Expression> fallback { UntypedExpr::createDeref( new UntypedExpr(new NameExpr(castExpr->concrete_target.getter), { castExpr->arg->clone() })) }; |
---|
| 1317 | // don't prune here, since it's guaranteed all alternatives will have the same type |
---|
| 1318 | finder.findWithoutPrune( fallback.get() ); |
---|
| 1319 | |
---|
| 1320 | pick_alternatives(finder.alternatives, true); |
---|
| 1321 | |
---|
| 1322 | // Whatever happens here, we have no more fallbacks |
---|
| 1323 | } |
---|
| 1324 | |
---|
[00ac42e] | 1325 | namespace { |
---|
| 1326 | /// Gets name from untyped member expression (member must be NameExpr) |
---|
| 1327 | const std::string& get_member_name( UntypedMemberExpr *memberExpr ) { |
---|
[30ee9efc] | 1328 | if ( dynamic_cast< ConstantExpr * >( memberExpr->get_member() ) ) { |
---|
| 1329 | SemanticError( memberExpr, "Indexed access to struct fields unsupported: " ); |
---|
| 1330 | } // if |
---|
[00ac42e] | 1331 | NameExpr * nameExpr = dynamic_cast< NameExpr * >( memberExpr->get_member() ); |
---|
| 1332 | assert( nameExpr ); |
---|
| 1333 | return nameExpr->get_name(); |
---|
| 1334 | } |
---|
| 1335 | } |
---|
| 1336 | |
---|
[13deae88] | 1337 | void AlternativeFinder::Finder::postvisit( UntypedMemberExpr *memberExpr ) { |
---|
[a32b204] | 1338 | AlternativeFinder funcFinder( indexer, env ); |
---|
| 1339 | funcFinder.findWithAdjustment( memberExpr->get_aggregate() ); |
---|
| 1340 | for ( AltList::const_iterator agg = funcFinder.alternatives.begin(); agg != funcFinder.alternatives.end(); ++agg ) { |
---|
[a61ad31] | 1341 | // it's okay for the aggregate expression to have reference type -- cast it to the base type to treat the aggregate as the referenced value |
---|
[a181494] | 1342 | Cost cost = agg->cost; |
---|
| 1343 | Expression * aggrExpr = agg->expr->clone(); |
---|
| 1344 | referenceToRvalueConversion( aggrExpr, cost ); |
---|
| 1345 | std::unique_ptr<Expression> guard( aggrExpr ); |
---|
| 1346 | |
---|
[a61ad31] | 1347 | // find member of the given type |
---|
| 1348 | if ( StructInstType *structInst = dynamic_cast< StructInstType* >( aggrExpr->get_result() ) ) { |
---|
[6d6e829] | 1349 | addAggMembers( structInst, aggrExpr, *agg, cost, get_member_name(memberExpr) ); |
---|
[a61ad31] | 1350 | } else if ( UnionInstType *unionInst = dynamic_cast< UnionInstType* >( aggrExpr->get_result() ) ) { |
---|
[6d6e829] | 1351 | addAggMembers( unionInst, aggrExpr, *agg, cost, get_member_name(memberExpr) ); |
---|
[a61ad31] | 1352 | } else if ( TupleType * tupleType = dynamic_cast< TupleType * >( aggrExpr->get_result() ) ) { |
---|
[6d6e829] | 1353 | addTupleMembers( tupleType, aggrExpr, *agg, cost, memberExpr->get_member() ); |
---|
[a32b204] | 1354 | } // if |
---|
| 1355 | } // for |
---|
| 1356 | } |
---|
| 1357 | |
---|
[13deae88] | 1358 | void AlternativeFinder::Finder::postvisit( MemberExpr *memberExpr ) { |
---|
[6d6e829] | 1359 | alternatives.push_back( Alternative{ memberExpr->clone(), env } ); |
---|
[a32b204] | 1360 | } |
---|
| 1361 | |
---|
[13deae88] | 1362 | void AlternativeFinder::Finder::postvisit( NameExpr *nameExpr ) { |
---|
[a40d503] | 1363 | std::list< SymTab::Indexer::IdData > declList; |
---|
[490ff5c3] | 1364 | indexer.lookupId( nameExpr->name, declList ); |
---|
| 1365 | PRINT( std::cerr << "nameExpr is " << nameExpr->name << std::endl; ) |
---|
[a40d503] | 1366 | for ( auto & data : declList ) { |
---|
[a181494] | 1367 | Cost cost = Cost::zero; |
---|
| 1368 | Expression * newExpr = data.combine( cost ); |
---|
[5de1e2c] | 1369 | |
---|
| 1370 | // addAnonAlternatives uses vector::push_back, which invalidates references to existing elements, so |
---|
| 1371 | // can't construct in place and use vector::back |
---|
[6d6e829] | 1372 | Alternative newAlt{ newExpr, env, OpenVarSet{}, AssertionList{}, Cost::zero, cost }; |
---|
[0f19d763] | 1373 | PRINT( |
---|
| 1374 | std::cerr << "decl is "; |
---|
[a40d503] | 1375 | data.id->print( std::cerr ); |
---|
[0f19d763] | 1376 | std::cerr << std::endl; |
---|
| 1377 | std::cerr << "newExpr is "; |
---|
[a40d503] | 1378 | newExpr->print( std::cerr ); |
---|
[0f19d763] | 1379 | std::cerr << std::endl; |
---|
[7c64920] | 1380 | ) |
---|
[5de1e2c] | 1381 | renameTypes( newAlt.expr ); |
---|
| 1382 | addAnonConversions( newAlt ); // add anonymous member interpretations whenever an aggregate value type is seen as a name expression. |
---|
| 1383 | alternatives.push_back( std::move(newAlt) ); |
---|
[0f19d763] | 1384 | } // for |
---|
[a32b204] | 1385 | } |
---|
| 1386 | |
---|
[13deae88] | 1387 | void AlternativeFinder::Finder::postvisit( VariableExpr *variableExpr ) { |
---|
[85517ddb] | 1388 | // not sufficient to clone here, because variable's type may have changed |
---|
| 1389 | // since the VariableExpr was originally created. |
---|
[6d6e829] | 1390 | alternatives.push_back( Alternative{ new VariableExpr{ variableExpr->var }, env } ); |
---|
[a32b204] | 1391 | } |
---|
| 1392 | |
---|
[13deae88] | 1393 | void AlternativeFinder::Finder::postvisit( ConstantExpr *constantExpr ) { |
---|
[6d6e829] | 1394 | alternatives.push_back( Alternative{ constantExpr->clone(), env } ); |
---|
[a32b204] | 1395 | } |
---|
| 1396 | |
---|
[13deae88] | 1397 | void AlternativeFinder::Finder::postvisit( SizeofExpr *sizeofExpr ) { |
---|
[a32b204] | 1398 | if ( sizeofExpr->get_isType() ) { |
---|
[322b97e] | 1399 | Type * newType = sizeofExpr->get_type()->clone(); |
---|
[6f096d2] | 1400 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1401 | new SizeofExpr{ resolveTypeof( newType, indexer ) }, env } ); |
---|
[a32b204] | 1402 | } else { |
---|
| 1403 | // find all alternatives for the argument to sizeof |
---|
| 1404 | AlternativeFinder finder( indexer, env ); |
---|
| 1405 | finder.find( sizeofExpr->get_expr() ); |
---|
| 1406 | // find the lowest cost alternative among the alternatives, otherwise ambiguous |
---|
| 1407 | AltList winners; |
---|
| 1408 | findMinCost( finder.alternatives.begin(), finder.alternatives.end(), back_inserter( winners ) ); |
---|
| 1409 | if ( winners.size() != 1 ) { |
---|
[a16764a6] | 1410 | SemanticError( sizeofExpr->get_expr(), "Ambiguous expression in sizeof operand: " ); |
---|
[a32b204] | 1411 | } // if |
---|
| 1412 | // return the lowest cost alternative for the argument |
---|
| 1413 | Alternative &choice = winners.front(); |
---|
[a181494] | 1414 | referenceToRvalueConversion( choice.expr, choice.cost ); |
---|
[6f096d2] | 1415 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1416 | choice, new SizeofExpr( choice.expr->clone() ), Cost::zero } ); |
---|
[47534159] | 1417 | } // if |
---|
| 1418 | } |
---|
| 1419 | |
---|
[13deae88] | 1420 | void AlternativeFinder::Finder::postvisit( AlignofExpr *alignofExpr ) { |
---|
[47534159] | 1421 | if ( alignofExpr->get_isType() ) { |
---|
[322b97e] | 1422 | Type * newType = alignofExpr->get_type()->clone(); |
---|
[6f096d2] | 1423 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1424 | new AlignofExpr{ resolveTypeof( newType, indexer ) }, env } ); |
---|
[47534159] | 1425 | } else { |
---|
| 1426 | // find all alternatives for the argument to sizeof |
---|
| 1427 | AlternativeFinder finder( indexer, env ); |
---|
| 1428 | finder.find( alignofExpr->get_expr() ); |
---|
| 1429 | // find the lowest cost alternative among the alternatives, otherwise ambiguous |
---|
| 1430 | AltList winners; |
---|
| 1431 | findMinCost( finder.alternatives.begin(), finder.alternatives.end(), back_inserter( winners ) ); |
---|
| 1432 | if ( winners.size() != 1 ) { |
---|
[a16764a6] | 1433 | SemanticError( alignofExpr->get_expr(), "Ambiguous expression in alignof operand: " ); |
---|
[47534159] | 1434 | } // if |
---|
| 1435 | // return the lowest cost alternative for the argument |
---|
| 1436 | Alternative &choice = winners.front(); |
---|
[a181494] | 1437 | referenceToRvalueConversion( choice.expr, choice.cost ); |
---|
[6f096d2] | 1438 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1439 | choice, new AlignofExpr{ choice.expr->clone() }, Cost::zero } ); |
---|
[a32b204] | 1440 | } // if |
---|
| 1441 | } |
---|
| 1442 | |
---|
[2a4b088] | 1443 | template< typename StructOrUnionType > |
---|
[13deae88] | 1444 | void AlternativeFinder::Finder::addOffsetof( StructOrUnionType *aggInst, const std::string &name ) { |
---|
[2a4b088] | 1445 | std::list< Declaration* > members; |
---|
| 1446 | aggInst->lookup( name, members ); |
---|
| 1447 | for ( std::list< Declaration* >::const_iterator i = members.begin(); i != members.end(); ++i ) { |
---|
| 1448 | if ( DeclarationWithType *dwt = dynamic_cast< DeclarationWithType* >( *i ) ) { |
---|
[6f096d2] | 1449 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1450 | new OffsetofExpr{ aggInst->clone(), dwt }, env } ); |
---|
[2a4b088] | 1451 | renameTypes( alternatives.back().expr ); |
---|
| 1452 | } else { |
---|
| 1453 | assert( false ); |
---|
| 1454 | } |
---|
| 1455 | } |
---|
| 1456 | } |
---|
[6ed1d4b] | 1457 | |
---|
[13deae88] | 1458 | void AlternativeFinder::Finder::postvisit( UntypedOffsetofExpr *offsetofExpr ) { |
---|
[2a4b088] | 1459 | AlternativeFinder funcFinder( indexer, env ); |
---|
[85517ddb] | 1460 | // xxx - resolveTypeof? |
---|
[2a4b088] | 1461 | if ( StructInstType *structInst = dynamic_cast< StructInstType* >( offsetofExpr->get_type() ) ) { |
---|
[490ff5c3] | 1462 | addOffsetof( structInst, offsetofExpr->member ); |
---|
[2a4b088] | 1463 | } else if ( UnionInstType *unionInst = dynamic_cast< UnionInstType* >( offsetofExpr->get_type() ) ) { |
---|
[490ff5c3] | 1464 | addOffsetof( unionInst, offsetofExpr->member ); |
---|
[2a4b088] | 1465 | } |
---|
| 1466 | } |
---|
[6ed1d4b] | 1467 | |
---|
[13deae88] | 1468 | void AlternativeFinder::Finder::postvisit( OffsetofExpr *offsetofExpr ) { |
---|
[6d6e829] | 1469 | alternatives.push_back( Alternative{ offsetofExpr->clone(), env } ); |
---|
[afc1045] | 1470 | } |
---|
| 1471 | |
---|
[13deae88] | 1472 | void AlternativeFinder::Finder::postvisit( OffsetPackExpr *offsetPackExpr ) { |
---|
[6d6e829] | 1473 | alternatives.push_back( Alternative{ offsetPackExpr->clone(), env } ); |
---|
[25a054f] | 1474 | } |
---|
| 1475 | |
---|
[6f096d2] | 1476 | void AlternativeFinder::Finder::postvisit( LogicalExpr * logicalExpr ) { |
---|
[a32b204] | 1477 | AlternativeFinder firstFinder( indexer, env ); |
---|
| 1478 | firstFinder.findWithAdjustment( logicalExpr->get_arg1() ); |
---|
[fee651f] | 1479 | if ( firstFinder.alternatives.empty() ) return; |
---|
| 1480 | AlternativeFinder secondFinder( indexer, env ); |
---|
| 1481 | secondFinder.findWithAdjustment( logicalExpr->get_arg2() ); |
---|
| 1482 | if ( secondFinder.alternatives.empty() ) return; |
---|
[490ff5c3] | 1483 | for ( const Alternative & first : firstFinder.alternatives ) { |
---|
| 1484 | for ( const Alternative & second : secondFinder.alternatives ) { |
---|
[6d6e829] | 1485 | TypeEnvironment compositeEnv{ first.env }; |
---|
[490ff5c3] | 1486 | compositeEnv.simpleCombine( second.env ); |
---|
[6d6e829] | 1487 | OpenVarSet openVars{ first.openVars }; |
---|
| 1488 | mergeOpenVars( openVars, second.openVars ); |
---|
[2c187378] | 1489 | AssertionSet need; |
---|
| 1490 | cloneAll( first.need, need ); |
---|
| 1491 | cloneAll( second.need, need ); |
---|
[6d6e829] | 1492 | |
---|
[6f096d2] | 1493 | LogicalExpr *newExpr = new LogicalExpr{ |
---|
[6d6e829] | 1494 | first.expr->clone(), second.expr->clone(), logicalExpr->get_isAnd() }; |
---|
[6f096d2] | 1495 | alternatives.push_back( Alternative{ |
---|
| 1496 | newExpr, std::move(compositeEnv), std::move(openVars), |
---|
[2c187378] | 1497 | AssertionList( need.begin(), need.end() ), first.cost + second.cost } ); |
---|
[d9a0e76] | 1498 | } |
---|
| 1499 | } |
---|
| 1500 | } |
---|
[51b7345] | 1501 | |
---|
[13deae88] | 1502 | void AlternativeFinder::Finder::postvisit( ConditionalExpr *conditionalExpr ) { |
---|
[32b8144] | 1503 | // find alternatives for condition |
---|
[a32b204] | 1504 | AlternativeFinder firstFinder( indexer, env ); |
---|
[624b722d] | 1505 | firstFinder.findWithAdjustment( conditionalExpr->arg1 ); |
---|
[ebcb7ba] | 1506 | if ( firstFinder.alternatives.empty() ) return; |
---|
| 1507 | // find alternatives for true expression |
---|
| 1508 | AlternativeFinder secondFinder( indexer, env ); |
---|
[624b722d] | 1509 | secondFinder.findWithAdjustment( conditionalExpr->arg2 ); |
---|
[ebcb7ba] | 1510 | if ( secondFinder.alternatives.empty() ) return; |
---|
| 1511 | // find alterantives for false expression |
---|
| 1512 | AlternativeFinder thirdFinder( indexer, env ); |
---|
[624b722d] | 1513 | thirdFinder.findWithAdjustment( conditionalExpr->arg3 ); |
---|
[ebcb7ba] | 1514 | if ( thirdFinder.alternatives.empty() ) return; |
---|
[624b722d] | 1515 | for ( const Alternative & first : firstFinder.alternatives ) { |
---|
| 1516 | for ( const Alternative & second : secondFinder.alternatives ) { |
---|
| 1517 | for ( const Alternative & third : thirdFinder.alternatives ) { |
---|
[6d6e829] | 1518 | TypeEnvironment compositeEnv{ first.env }; |
---|
[624b722d] | 1519 | compositeEnv.simpleCombine( second.env ); |
---|
| 1520 | compositeEnv.simpleCombine( third.env ); |
---|
[6d6e829] | 1521 | OpenVarSet openVars{ first.openVars }; |
---|
| 1522 | mergeOpenVars( openVars, second.openVars ); |
---|
| 1523 | mergeOpenVars( openVars, third.openVars ); |
---|
[2c187378] | 1524 | AssertionSet need; |
---|
| 1525 | cloneAll( first.need, need ); |
---|
| 1526 | cloneAll( second.need, need ); |
---|
| 1527 | cloneAll( third.need, need ); |
---|
| 1528 | AssertionSet have; |
---|
[6f096d2] | 1529 | |
---|
[32b8144] | 1530 | // unify true and false types, then infer parameters to produce new alternatives |
---|
[668e971a] | 1531 | Type* commonType = nullptr; |
---|
[6f096d2] | 1532 | if ( unify( second.expr->result, third.expr->result, compositeEnv, |
---|
[2c187378] | 1533 | need, have, openVars, indexer, commonType ) ) { |
---|
[6f096d2] | 1534 | ConditionalExpr *newExpr = new ConditionalExpr{ |
---|
[6d6e829] | 1535 | first.expr->clone(), second.expr->clone(), third.expr->clone() }; |
---|
[624b722d] | 1536 | newExpr->result = commonType ? commonType : second.expr->result->clone(); |
---|
[ddf8a29] | 1537 | // convert both options to the conditional result type |
---|
[6d6e829] | 1538 | Cost cost = first.cost + second.cost + third.cost; |
---|
[6f096d2] | 1539 | cost += computeExpressionConversionCost( |
---|
[6d6e829] | 1540 | newExpr->arg2, newExpr->result, indexer, compositeEnv ); |
---|
[6f096d2] | 1541 | cost += computeExpressionConversionCost( |
---|
[6d6e829] | 1542 | newExpr->arg3, newExpr->result, indexer, compositeEnv ); |
---|
| 1543 | // output alternative |
---|
[6f096d2] | 1544 | Alternative newAlt{ |
---|
| 1545 | newExpr, std::move(compositeEnv), std::move(openVars), |
---|
[2c187378] | 1546 | AssertionList( need.begin(), need.end() ), cost }; |
---|
[0b00df0] | 1547 | inferParameters( newAlt, back_inserter( alternatives ) ); |
---|
[a32b204] | 1548 | } // if |
---|
| 1549 | } // for |
---|
| 1550 | } // for |
---|
| 1551 | } // for |
---|
| 1552 | } |
---|
| 1553 | |
---|
[13deae88] | 1554 | void AlternativeFinder::Finder::postvisit( CommaExpr *commaExpr ) { |
---|
[a32b204] | 1555 | TypeEnvironment newEnv( env ); |
---|
| 1556 | Expression *newFirstArg = resolveInVoidContext( commaExpr->get_arg1(), indexer, newEnv ); |
---|
| 1557 | AlternativeFinder secondFinder( indexer, newEnv ); |
---|
| 1558 | secondFinder.findWithAdjustment( commaExpr->get_arg2() ); |
---|
[490ff5c3] | 1559 | for ( const Alternative & alt : secondFinder.alternatives ) { |
---|
[6f096d2] | 1560 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1561 | alt, new CommaExpr{ newFirstArg->clone(), alt.expr->clone() }, alt.cost } ); |
---|
[a32b204] | 1562 | } // for |
---|
| 1563 | delete newFirstArg; |
---|
| 1564 | } |
---|
| 1565 | |
---|
[13deae88] | 1566 | void AlternativeFinder::Finder::postvisit( RangeExpr * rangeExpr ) { |
---|
[32b8144] | 1567 | // resolve low and high, accept alternatives whose low and high types unify |
---|
| 1568 | AlternativeFinder firstFinder( indexer, env ); |
---|
[490ff5c3] | 1569 | firstFinder.findWithAdjustment( rangeExpr->low ); |
---|
[fee651f] | 1570 | if ( firstFinder.alternatives.empty() ) return; |
---|
| 1571 | AlternativeFinder secondFinder( indexer, env ); |
---|
[490ff5c3] | 1572 | secondFinder.findWithAdjustment( rangeExpr->high ); |
---|
[fee651f] | 1573 | if ( secondFinder.alternatives.empty() ) return; |
---|
[490ff5c3] | 1574 | for ( const Alternative & first : firstFinder.alternatives ) { |
---|
| 1575 | for ( const Alternative & second : secondFinder.alternatives ) { |
---|
[6d6e829] | 1576 | TypeEnvironment compositeEnv{ first.env }; |
---|
[490ff5c3] | 1577 | compositeEnv.simpleCombine( second.env ); |
---|
[6d6e829] | 1578 | OpenVarSet openVars{ first.openVars }; |
---|
| 1579 | mergeOpenVars( openVars, second.openVars ); |
---|
[2c187378] | 1580 | AssertionSet need; |
---|
| 1581 | cloneAll( first.need, need ); |
---|
| 1582 | cloneAll( second.need, need ); |
---|
| 1583 | AssertionSet have; |
---|
[6d6e829] | 1584 | |
---|
[32b8144] | 1585 | Type* commonType = nullptr; |
---|
[6f096d2] | 1586 | if ( unify( first.expr->result, second.expr->result, compositeEnv, need, have, |
---|
[2c187378] | 1587 | openVars, indexer, commonType ) ) { |
---|
[6f096d2] | 1588 | RangeExpr * newExpr = |
---|
[6d6e829] | 1589 | new RangeExpr{ first.expr->clone(), second.expr->clone() }; |
---|
[490ff5c3] | 1590 | newExpr->result = commonType ? commonType : first.expr->result->clone(); |
---|
[6f096d2] | 1591 | Alternative newAlt{ |
---|
| 1592 | newExpr, std::move(compositeEnv), std::move(openVars), |
---|
[2c187378] | 1593 | AssertionList( need.begin(), need.end() ), first.cost + second.cost }; |
---|
[0b00df0] | 1594 | inferParameters( newAlt, back_inserter( alternatives ) ); |
---|
[32b8144] | 1595 | } // if |
---|
| 1596 | } // for |
---|
| 1597 | } // for |
---|
| 1598 | } |
---|
| 1599 | |
---|
[13deae88] | 1600 | void AlternativeFinder::Finder::postvisit( UntypedTupleExpr *tupleExpr ) { |
---|
[bd4f2e9] | 1601 | std::vector< AlternativeFinder > subExprAlternatives; |
---|
[13deae88] | 1602 | altFinder.findSubExprs( tupleExpr->get_exprs().begin(), tupleExpr->get_exprs().end(), |
---|
[bd4f2e9] | 1603 | back_inserter( subExprAlternatives ) ); |
---|
| 1604 | std::vector< AltList > possibilities; |
---|
[452747a] | 1605 | combos( subExprAlternatives.begin(), subExprAlternatives.end(), |
---|
[bd4f2e9] | 1606 | back_inserter( possibilities ) ); |
---|
| 1607 | for ( const AltList& alts : possibilities ) { |
---|
[907eccb] | 1608 | std::list< Expression * > exprs; |
---|
[bd4f2e9] | 1609 | makeExprList( alts, exprs ); |
---|
[a32b204] | 1610 | |
---|
| 1611 | TypeEnvironment compositeEnv; |
---|
[6d6e829] | 1612 | OpenVarSet openVars; |
---|
| 1613 | AssertionSet need; |
---|
| 1614 | for ( const Alternative& alt : alts ) { |
---|
| 1615 | compositeEnv.simpleCombine( alt.env ); |
---|
| 1616 | mergeOpenVars( openVars, alt.openVars ); |
---|
[2c187378] | 1617 | cloneAll( alt.need, need ); |
---|
[6d6e829] | 1618 | } |
---|
[6f096d2] | 1619 | |
---|
| 1620 | alternatives.push_back( Alternative{ |
---|
| 1621 | new TupleExpr{ exprs }, std::move(compositeEnv), std::move(openVars), |
---|
[6d6e829] | 1622 | AssertionList( need.begin(), need.end() ), sumCost( alts ) } ); |
---|
[a32b204] | 1623 | } // for |
---|
[d9a0e76] | 1624 | } |
---|
[dc2e7e0] | 1625 | |
---|
[13deae88] | 1626 | void AlternativeFinder::Finder::postvisit( TupleExpr *tupleExpr ) { |
---|
[6d6e829] | 1627 | alternatives.push_back( Alternative{ tupleExpr->clone(), env } ); |
---|
[907eccb] | 1628 | } |
---|
| 1629 | |
---|
[13deae88] | 1630 | void AlternativeFinder::Finder::postvisit( ImplicitCopyCtorExpr * impCpCtorExpr ) { |
---|
[6d6e829] | 1631 | alternatives.push_back( Alternative{ impCpCtorExpr->clone(), env } ); |
---|
[dc2e7e0] | 1632 | } |
---|
[b6fe7e6] | 1633 | |
---|
[13deae88] | 1634 | void AlternativeFinder::Finder::postvisit( ConstructorExpr * ctorExpr ) { |
---|
[b6fe7e6] | 1635 | AlternativeFinder finder( indexer, env ); |
---|
| 1636 | // don't prune here, since it's guaranteed all alternatives will have the same type |
---|
| 1637 | // (giving the alternatives different types is half of the point of ConstructorExpr nodes) |
---|
[4e66a18] | 1638 | finder.findWithoutPrune( ctorExpr->get_callExpr() ); |
---|
[b6fe7e6] | 1639 | for ( Alternative & alt : finder.alternatives ) { |
---|
[6f096d2] | 1640 | alternatives.push_back( Alternative{ |
---|
[6d6e829] | 1641 | alt, new ConstructorExpr( alt.expr->clone() ), alt.cost } ); |
---|
[b6fe7e6] | 1642 | } |
---|
| 1643 | } |
---|
[8f7cea1] | 1644 | |
---|
[13deae88] | 1645 | void AlternativeFinder::Finder::postvisit( TupleIndexExpr *tupleExpr ) { |
---|
[6d6e829] | 1646 | alternatives.push_back( Alternative{ tupleExpr->clone(), env } ); |
---|
[8f7cea1] | 1647 | } |
---|
[aa8f9df] | 1648 | |
---|
[13deae88] | 1649 | void AlternativeFinder::Finder::postvisit( TupleAssignExpr *tupleAssignExpr ) { |
---|
[6d6e829] | 1650 | alternatives.push_back( Alternative{ tupleAssignExpr->clone(), env } ); |
---|
[aa8f9df] | 1651 | } |
---|
[bf32bb8] | 1652 | |
---|
[13deae88] | 1653 | void AlternativeFinder::Finder::postvisit( UniqueExpr *unqExpr ) { |
---|
[bf32bb8] | 1654 | AlternativeFinder finder( indexer, env ); |
---|
| 1655 | finder.findWithAdjustment( unqExpr->get_expr() ); |
---|
| 1656 | for ( Alternative & alt : finder.alternatives ) { |
---|
[141b786] | 1657 | // ensure that the id is passed on to the UniqueExpr alternative so that the expressions are "linked" |
---|
[77971f6] | 1658 | UniqueExpr * newUnqExpr = new UniqueExpr( alt.expr->clone(), unqExpr->get_id() ); |
---|
[6d6e829] | 1659 | alternatives.push_back( Alternative{ alt, newUnqExpr, alt.cost } ); |
---|
[bf32bb8] | 1660 | } |
---|
| 1661 | } |
---|
| 1662 | |
---|
[13deae88] | 1663 | void AlternativeFinder::Finder::postvisit( StmtExpr *stmtExpr ) { |
---|
[722617d] | 1664 | StmtExpr * newStmtExpr = stmtExpr->clone(); |
---|
| 1665 | ResolvExpr::resolveStmtExpr( newStmtExpr, indexer ); |
---|
| 1666 | // xxx - this env is almost certainly wrong, and needs to somehow contain the combined environments from all of the statements in the stmtExpr... |
---|
[6d6e829] | 1667 | alternatives.push_back( Alternative{ newStmtExpr, env } ); |
---|
[722617d] | 1668 | } |
---|
| 1669 | |
---|
[13deae88] | 1670 | void AlternativeFinder::Finder::postvisit( UntypedInitExpr *initExpr ) { |
---|
[62423350] | 1671 | // handle each option like a cast |
---|
[e4d829b] | 1672 | AltList candidates; |
---|
[13deae88] | 1673 | PRINT( |
---|
| 1674 | std::cerr << "untyped init expr: " << initExpr << std::endl; |
---|
| 1675 | ) |
---|
[e4d829b] | 1676 | // O(N^2) checks of d-types with e-types |
---|
[62423350] | 1677 | for ( InitAlternative & initAlt : initExpr->get_initAlts() ) { |
---|
[228099e] | 1678 | Type * toType = resolveTypeof( initAlt.type->clone(), indexer ); |
---|
[62423350] | 1679 | SymTab::validateType( toType, &indexer ); |
---|
| 1680 | adjustExprType( toType, env, indexer ); |
---|
| 1681 | // Ideally the call to findWithAdjustment could be moved out of the loop, but unfortunately it currently has to occur inside or else |
---|
| 1682 | // polymorphic return types are not properly bound to the initialization type, since return type variables are only open for the duration of resolving |
---|
| 1683 | // the UntypedExpr. This is only actually an issue in initialization contexts that allow more than one possible initialization type, but it is still suboptimal. |
---|
| 1684 | AlternativeFinder finder( indexer, env ); |
---|
| 1685 | finder.targetType = toType; |
---|
[3d2ae8d] | 1686 | finder.findWithAdjustment( initExpr->expr ); |
---|
[62423350] | 1687 | for ( Alternative & alt : finder.get_alternatives() ) { |
---|
| 1688 | TypeEnvironment newEnv( alt.env ); |
---|
[2c187378] | 1689 | AssertionSet need; |
---|
| 1690 | cloneAll( alt.need, need ); |
---|
| 1691 | AssertionSet have; |
---|
[6f096d2] | 1692 | OpenVarSet openVars( alt.openVars ); |
---|
| 1693 | // xxx - find things in env that don't have a "representative type" and claim |
---|
[6d6e829] | 1694 | // those are open vars? |
---|
[13deae88] | 1695 | PRINT( |
---|
| 1696 | std::cerr << " @ " << toType << " " << initAlt.designation << std::endl; |
---|
[3d2ae8d] | 1697 | ) |
---|
[6f096d2] | 1698 | // It's possible that a cast can throw away some values in a multiply-valued |
---|
| 1699 | // expression. (An example is a cast-to-void, which casts from one value to |
---|
| 1700 | // zero.) Figure out the prefix of the subexpression results that are cast |
---|
| 1701 | // directly. The candidate is invalid if it has fewer results than there are |
---|
[6d6e829] | 1702 | // types to cast to. |
---|
[3d2ae8d] | 1703 | int discardedValues = alt.expr->result->size() - toType->size(); |
---|
[e4d829b] | 1704 | if ( discardedValues < 0 ) continue; |
---|
[6f096d2] | 1705 | // xxx - may need to go into tuple types and extract relevant types and use |
---|
| 1706 | // unifyList. Note that currently, this does not allow casting a tuple to an |
---|
[6d6e829] | 1707 | // atomic type (e.g. (int)([1, 2, 3])) |
---|
[6f096d2] | 1708 | |
---|
[e4d829b] | 1709 | // unification run for side-effects |
---|
[b81fd95] | 1710 | bool canUnify = unify( toType, alt.expr->result, newEnv, need, have, openVars, indexer ); |
---|
| 1711 | (void) canUnify; |
---|
[6d6e829] | 1712 | // xxx - do some inspecting on this line... why isn't result bound to initAlt.type? |
---|
[e4d829b] | 1713 | |
---|
[b81fd95] | 1714 | Cost thisCost = computeConversionCost( alt.expr->result, toType, alt.expr->get_lvalue(), |
---|
[7d01cf44] | 1715 | indexer, newEnv ); |
---|
[b81fd95] | 1716 | |
---|
| 1717 | PRINT( |
---|
| 1718 | Cost legacyCost = castCost( alt.expr->result, toType, alt.expr->get_lvalue(), |
---|
| 1719 | indexer, newEnv ); |
---|
| 1720 | std::cerr << "Considering initialization:"; |
---|
| 1721 | std::cerr << std::endl << " FROM: "; alt.expr->result->print(std::cerr); |
---|
| 1722 | std::cerr << std::endl << " TO: "; toType ->print(std::cerr); |
---|
| 1723 | std::cerr << std::endl << " Unification " << (canUnify ? "succeeded" : "failed"); |
---|
| 1724 | std::cerr << std::endl << " Legacy cost " << legacyCost; |
---|
| 1725 | std::cerr << std::endl << " New cost " << thisCost; |
---|
| 1726 | std::cerr << std::endl; |
---|
| 1727 | ) |
---|
[1db306a] | 1728 | |
---|
[e4d829b] | 1729 | if ( thisCost != Cost::infinity ) { |
---|
| 1730 | // count one safe conversion for each value that is thrown away |
---|
[89be1c68] | 1731 | thisCost.incSafe( discardedValues ); |
---|
[6f096d2] | 1732 | Alternative newAlt{ |
---|
| 1733 | new InitExpr{ |
---|
| 1734 | restructureCast( alt.expr->clone(), toType, true ), initAlt.designation->clone() }, |
---|
| 1735 | std::move(newEnv), std::move(openVars), |
---|
[2c187378] | 1736 | AssertionList( need.begin(), need.end() ), alt.cost, thisCost }; |
---|
[0b00df0] | 1737 | inferParameters( newAlt, back_inserter( candidates ) ); |
---|
[e4d829b] | 1738 | } |
---|
| 1739 | } |
---|
| 1740 | } |
---|
| 1741 | |
---|
| 1742 | // findMinCost selects the alternatives with the lowest "cost" members, but has the side effect of copying the |
---|
| 1743 | // cvtCost member to the cost member (since the old cost is now irrelevant). Thus, calling findMinCost twice |
---|
| 1744 | // selects first based on argument cost, then on conversion cost. |
---|
| 1745 | AltList minArgCost; |
---|
| 1746 | findMinCost( candidates.begin(), candidates.end(), std::back_inserter( minArgCost ) ); |
---|
| 1747 | findMinCost( minArgCost.begin(), minArgCost.end(), std::back_inserter( alternatives ) ); |
---|
| 1748 | } |
---|
[c71b256] | 1749 | |
---|
| 1750 | void AlternativeFinder::Finder::postvisit( InitExpr * ) { |
---|
| 1751 | assertf( false, "AlternativeFinder should never see a resolved InitExpr." ); |
---|
| 1752 | } |
---|
| 1753 | |
---|
| 1754 | void AlternativeFinder::Finder::postvisit( DeletedExpr * ) { |
---|
| 1755 | assertf( false, "AlternativeFinder should never see a DeletedExpr." ); |
---|
| 1756 | } |
---|
[d807ca28] | 1757 | |
---|
| 1758 | void AlternativeFinder::Finder::postvisit( GenericExpr * ) { |
---|
| 1759 | assertf( false, "_Generic is not yet supported." ); |
---|
| 1760 | } |
---|
[51b7345] | 1761 | } // namespace ResolvExpr |
---|
[a32b204] | 1762 | |
---|
| 1763 | // Local Variables: // |
---|
| 1764 | // tab-width: 4 // |
---|
| 1765 | // mode: c++ // |
---|
| 1766 | // compile-command: "make install" // |
---|
| 1767 | // End: // |
---|