| 1 | //
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
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| 3 | //
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| 4 | // The contents of this file are covered under the licence agreement in the
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| 5 | // file "LICENCE" distributed with Cforall.
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| 6 | //
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| 7 | // CastCost.cc -- 
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| 8 | //
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| 9 | // Author           : Richard C. Bilson
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| 10 | // Created On       : Sun May 17 06:57:43 2015
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| 11 | // Last Modified By : Rob Schluntz
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| 12 | // Last Modified On : Mon Oct 05 14:48:45 2015
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| 13 | // Update Count     : 5
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| 14 | //
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| 15 | 
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| 16 | #include "typeops.h"
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| 17 | #include "Cost.h"
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| 18 | #include "ConversionCost.h"
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| 19 | #include "SynTree/Type.h"
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| 20 | #include "SynTree/Visitor.h"
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| 21 | #include "SymTab/Indexer.h"
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| 22 | 
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| 23 | 
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| 24 | namespace ResolvExpr {
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| 25 |         class CastCost : public ConversionCost {
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| 26 |           public:
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| 27 |                 CastCost( Type *dest, const SymTab::Indexer &indexer, const TypeEnvironment &env );
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| 28 |   
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| 29 |                 virtual void visit( BasicType *basicType );
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| 30 |                 virtual void visit( PointerType *pointerType );
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| 31 |         };
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| 32 | 
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| 33 |         Cost castCost( Type *src, Type *dest, const SymTab::Indexer &indexer, const TypeEnvironment &env ) {
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| 34 |                 if ( TypeInstType *destAsTypeInst = dynamic_cast< TypeInstType* >( dest ) ) {
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| 35 |                         EqvClass eqvClass;
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| 36 |                         NamedTypeDecl *namedType;
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| 37 |                         if ( env.lookup( destAsTypeInst->get_name(), eqvClass ) ) {
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| 38 |                                 return castCost( src, eqvClass.type, indexer, env );
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| 39 |                         } else if ( ( namedType = indexer.lookupType( destAsTypeInst->get_name() ) ) ) {
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| 40 |                                 TypeDecl *type = dynamic_cast< TypeDecl* >( namedType );
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| 41 |                                 // all typedefs should be gone by this point
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| 42 |                                 assert( type );
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| 43 |                                 if ( type->get_base() ) {
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| 44 |                                         return castCost( src, type->get_base(), indexer, env ) + Cost( 0, 0, 1 );
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| 45 |                                 } // if
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| 46 |                         } // if
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| 47 |                 } // if
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| 48 |                 if ( typesCompatibleIgnoreQualifiers( src, dest, indexer, env ) ) {
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| 49 |                         return Cost( 0, 0, 0 );
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| 50 |                 } else if ( dynamic_cast< VoidType* >( dest ) ) {
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| 51 |                         return Cost( 0, 0, 1 );
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| 52 |                 } else {
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| 53 |                         CastCost converter( dest, indexer, env );
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| 54 |                         src->accept( converter );
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| 55 |                         if ( converter.get_cost() == Cost::infinity ) {
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| 56 |                                 return Cost::infinity;
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| 57 |                         } else {
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| 58 |                                 // xxx - why are we adding cost 0 here?
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| 59 |                                 return converter.get_cost() + Cost( 0, 0, 0 );
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| 60 |                         } // if
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| 61 |                 } // if
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| 62 |         }
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| 63 | 
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| 64 |         CastCost::CastCost( Type *dest, const SymTab::Indexer &indexer, const TypeEnvironment &env )
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| 65 |                 : ConversionCost( dest, indexer, env ) {
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| 66 |         }
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| 67 | 
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| 68 |         void CastCost::visit( BasicType *basicType ) {
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| 69 |                 PointerType *destAsPointer = dynamic_cast< PointerType* >( dest );
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| 70 |                 if ( destAsPointer && basicType->isInteger() ) {
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| 71 |                         cost = Cost( 1, 0, 0 );
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| 72 |                 } else {
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| 73 |                         ConversionCost::visit( basicType );
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| 74 |                 } // if
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| 75 |         }
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| 76 | 
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| 77 |         void CastCost::visit( PointerType *pointerType ) {
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| 78 |                 if ( PointerType *destAsPtr = dynamic_cast< PointerType* >( dest ) ) {
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| 79 |                         if ( pointerType->get_qualifiers() <= destAsPtr->get_qualifiers() && typesCompatibleIgnoreQualifiers( pointerType->get_base(), destAsPtr->get_base(), indexer, env ) ) {
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| 80 |                                 cost = Cost( 0, 0, 1 );
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| 81 |                         } else {
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| 82 |                                 TypeEnvironment newEnv( env );
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| 83 |                                 newEnv.add( pointerType->get_forall() );
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| 84 |                                 newEnv.add( pointerType->get_base()->get_forall() );
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| 85 |                                 int castResult = ptrsCastable( pointerType->get_base(), destAsPtr->get_base(), newEnv, indexer );
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| 86 |                                 if ( castResult > 0 ) {
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| 87 |                                         cost = Cost( 0, 0, 1 );
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| 88 |                                 } else if ( castResult < 0 ) {
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| 89 |                                         cost = Cost( 1, 0, 0 );
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| 90 |                                 } // if
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| 91 |                         } // if
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| 92 |                 } else if ( BasicType *destAsBasic = dynamic_cast< BasicType* >( dest ) ) {
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| 93 |                         if ( destAsBasic->isInteger() ) {
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| 94 |                                 cost = Cost( 1, 0, 0 );
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| 95 |                         } // if
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| 96 |                 }
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| 97 |         }
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| 98 | } // namespace ResolvExpr
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| 99 | 
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| 100 | // Local Variables: //
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| 101 | // tab-width: 4 //
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| 102 | // mode: c++ //
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| 103 | // compile-command: "make install" //
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| 104 | // End: //
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