| [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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| [a436947] | 7 | // ConversionCost.cc -- | 
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| [a32b204] | 8 | // | 
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|  | 9 | // Author           : Richard C. Bilson | 
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|  | 10 | // Created On       : Sun May 17 07:06:19 2015 | 
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|  | 11 | // Last Modified By : Peter A. Buhr | 
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| [201aeb9] | 12 | // Last Modified On : Mon Sep 25 15:43:34 2017 | 
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|  | 13 | // Update Count     : 10 | 
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| [a32b204] | 14 | // | 
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| [51b73452] | 15 |  | 
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|  | 16 | #include "ConversionCost.h" | 
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| [ea6332d] | 17 |  | 
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|  | 18 | #include <cassert>                       // for assert | 
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|  | 19 | #include <list>                          // for list, list<>::const_iterator | 
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|  | 20 | #include <string>                        // for operator==, string | 
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|  | 21 |  | 
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|  | 22 | #include "ResolvExpr/Cost.h"             // for Cost | 
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|  | 23 | #include "ResolvExpr/TypeEnvironment.h"  // for EqvClass, TypeEnvironment | 
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|  | 24 | #include "SymTab/Indexer.h"              // for Indexer | 
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|  | 25 | #include "SynTree/Declaration.h"         // for TypeDecl, NamedTypeDecl | 
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|  | 26 | #include "SynTree/Type.h"                // for Type, BasicType, TypeInstType | 
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|  | 27 | #include "typeops.h"                     // for typesCompatibleIgnoreQualifiers | 
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| [51b73452] | 28 |  | 
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|  | 29 | namespace ResolvExpr { | 
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| [7ebaa56] | 30 | const Cost Cost::zero = Cost( 0, 0, 0, 0 ); | 
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|  | 31 | const Cost Cost::infinity = Cost( -1, -1, -1, -1 ); | 
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|  | 32 | const Cost Cost::unsafe = Cost( 1, 0, 0, 0 ); | 
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|  | 33 | const Cost Cost::poly = Cost( 0, 1, 0, 0 ); | 
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|  | 34 | const Cost Cost::safe = Cost( 0, 0, 1, 0 ); | 
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|  | 35 | const Cost Cost::reference = Cost( 0, 0, 0, 1 ); | 
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| [b46e3bd] | 36 |  | 
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| [5ccb10d] | 37 | #if 0 | 
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|  | 38 | #define PRINT(x) x | 
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|  | 39 | #else | 
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|  | 40 | #define PRINT(x) | 
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|  | 41 | #endif | 
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| [a32b204] | 42 | Cost conversionCost( Type *src, Type *dest, const SymTab::Indexer &indexer, const TypeEnvironment &env ) { | 
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|  | 43 | if ( TypeInstType *destAsTypeInst = dynamic_cast< TypeInstType* >( dest ) ) { | 
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|  | 44 | EqvClass eqvClass; | 
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|  | 45 | NamedTypeDecl *namedType; | 
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| [5ccb10d] | 46 | PRINT( std::cerr << "type inst " << destAsTypeInst->get_name(); ) | 
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| [a32b204] | 47 | if ( env.lookup( destAsTypeInst->get_name(), eqvClass ) ) { | 
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| [0b150ec] | 48 | if ( eqvClass.type ) { | 
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|  | 49 | return conversionCost( src, eqvClass.type, indexer, env ); | 
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|  | 50 | } else { | 
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|  | 51 | return Cost::infinity; | 
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|  | 52 | } | 
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| [a32b204] | 53 | } else if ( ( namedType = indexer.lookupType( destAsTypeInst->get_name() ) ) ) { | 
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| [5ccb10d] | 54 | PRINT( std::cerr << " found" << std::endl; ) | 
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| [a32b204] | 55 | TypeDecl *type = dynamic_cast< TypeDecl* >( namedType ); | 
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|  | 56 | // all typedefs should be gone by this point | 
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|  | 57 | assert( type ); | 
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|  | 58 | if ( type->get_base() ) { | 
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| [89be1c68] | 59 | return conversionCost( src, type->get_base(), indexer, env ) + Cost::safe; | 
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| [a32b204] | 60 | } // if | 
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|  | 61 | } // if | 
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| [5ccb10d] | 62 | PRINT( std::cerr << " not found" << std::endl; ) | 
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| [a32b204] | 63 | } // if | 
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| [5ccb10d] | 64 | PRINT( | 
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|  | 65 | std::cerr << "src is "; | 
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|  | 66 | src->print( std::cerr ); | 
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|  | 67 | std::cerr << std::endl << "dest is "; | 
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|  | 68 | dest->print( std::cerr ); | 
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|  | 69 | std::cerr << std::endl << "env is" << std::endl; | 
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|  | 70 | env.print( std::cerr, 8 ); | 
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|  | 71 | ) | 
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| [a32b204] | 72 | if ( typesCompatibleIgnoreQualifiers( src, dest, indexer, env ) ) { | 
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| [5ccb10d] | 73 | PRINT( std::cerr << "compatible!" << std::endl; ) | 
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| [89be1c68] | 74 | return Cost::zero; | 
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| [a32b204] | 75 | } else if ( dynamic_cast< VoidType* >( dest ) ) { | 
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| [89be1c68] | 76 | return Cost::safe; | 
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| [2463d0e] | 77 | } else if ( ReferenceType * refType = dynamic_cast< ReferenceType * > ( dest ) ) { | 
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| [5ccb10d] | 78 | PRINT( std::cerr << "conversionCost: dest is reference" << std::endl; ) | 
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| [0c6596f] | 79 | return convertToReferenceCost( src, refType, indexer, env, [](Type * t1, Type * t2, const TypeEnvironment & env, const SymTab::Indexer &){ | 
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|  | 80 | return ptrsAssignable( t1, t2, env ); | 
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|  | 81 | }); | 
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| [a32b204] | 82 | } else { | 
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|  | 83 | ConversionCost converter( dest, indexer, env ); | 
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|  | 84 | src->accept( converter ); | 
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|  | 85 | if ( converter.get_cost() == Cost::infinity ) { | 
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|  | 86 | return Cost::infinity; | 
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|  | 87 | } else { | 
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| [89be1c68] | 88 | return converter.get_cost() + Cost::zero; | 
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| [a32b204] | 89 | } // if | 
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|  | 90 | } // if | 
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|  | 91 | } | 
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|  | 92 |  | 
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| [0c6596f] | 93 | Cost convertToReferenceCost( Type * src, Type * dest, int diff, const SymTab::Indexer & indexer, const TypeEnvironment & env, PtrsFunction func ) { | 
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| [108f3cdb] | 94 | PRINT( std::cerr << "convert to reference cost... diff " << diff << std::endl; ) | 
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| [89be1c68] | 95 | if ( diff > 0 ) { | 
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|  | 96 | // TODO: document this | 
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| [e3e16bc] | 97 | Cost cost = convertToReferenceCost( strict_dynamic_cast< ReferenceType * >( src )->get_base(), dest, diff-1, indexer, env, func ); | 
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| [7ebaa56] | 98 | cost.incReference(); | 
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| [89be1c68] | 99 | return cost; | 
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|  | 100 | } else if ( diff < -1 ) { | 
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|  | 101 | // TODO: document this | 
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| [e3e16bc] | 102 | Cost cost = convertToReferenceCost( src, strict_dynamic_cast< ReferenceType * >( dest )->get_base(), diff+1, indexer, env, func ); | 
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| [7ebaa56] | 103 | cost.incReference(); | 
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| [89be1c68] | 104 | return cost; | 
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|  | 105 | } else if ( diff == 0 ) { | 
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|  | 106 | ReferenceType * srcAsRef = dynamic_cast< ReferenceType * >( src ); | 
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|  | 107 | ReferenceType * destAsRef = dynamic_cast< ReferenceType * >( dest ); | 
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|  | 108 | if ( srcAsRef && destAsRef ) { // pointer-like conversions between references | 
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| [5ccb10d] | 109 | PRINT( std::cerr << "converting between references" << std::endl; ) | 
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| [89be1c68] | 110 | if ( srcAsRef->get_base()->get_qualifiers() <= destAsRef->get_base()->get_qualifiers() && typesCompatibleIgnoreQualifiers( srcAsRef->get_base(), destAsRef->get_base(), indexer, env ) ) { | 
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|  | 111 | return Cost::safe; | 
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|  | 112 | } else {  // xxx - this discards reference qualifiers from consideration -- reducing qualifiers is a safe conversion; is this right? | 
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| [0c6596f] | 113 | int assignResult = func( srcAsRef->get_base(), destAsRef->get_base(), env, indexer ); | 
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| [5ccb10d] | 114 | PRINT( std::cerr << "comparing references: " << assignResult << " " << srcAsRef << " " << destAsRef << std::endl; ) | 
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| [89be1c68] | 115 | if ( assignResult < 0 ) { | 
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|  | 116 | return Cost::safe; | 
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|  | 117 | } else if ( assignResult > 0 ) { | 
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|  | 118 | return Cost::unsafe; | 
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|  | 119 | } // if | 
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| [2463d0e] | 120 | } // if | 
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|  | 121 | } else { | 
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| [5ccb10d] | 122 | PRINT( std::cerr << "reference to rvalue conversion" << std::endl; ) | 
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| [89be1c68] | 123 | ConversionCost converter( dest, indexer, env ); | 
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|  | 124 | src->accept( converter ); | 
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|  | 125 | return converter.get_cost(); | 
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|  | 126 | } // if | 
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| [2463d0e] | 127 | } else { | 
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| [89be1c68] | 128 | ReferenceType * destAsRef = dynamic_cast< ReferenceType * >( dest ); | 
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|  | 129 | assert( diff == -1 && destAsRef ); | 
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| [108f3cdb] | 130 | PRINT( std::cerr << "dest is: " << dest << " / src is: " << src << std::endl; ) | 
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| [89be1c68] | 131 | if ( typesCompatibleIgnoreQualifiers( src, destAsRef->get_base(), indexer, env ) ) { | 
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| [5ccb10d] | 132 | PRINT( std::cerr << "converting compatible base type" << std::endl; ) | 
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| [89be1c68] | 133 | if ( src->get_lvalue() ) { | 
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| [5ccb10d] | 134 | PRINT( | 
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|  | 135 | std::cerr << "lvalue to reference conversion" << std::endl; | 
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|  | 136 | std::cerr << src << " => " << destAsRef << std::endl; | 
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|  | 137 | ) | 
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| [89be1c68] | 138 | // lvalue-to-reference conversion:  cv lvalue T => cv T & | 
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|  | 139 | if ( src->get_qualifiers() == destAsRef->get_base()->get_qualifiers() ) { | 
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| [7ebaa56] | 140 | return Cost::reference; // cost needs to be non-zero to add cast | 
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| [89be1c68] | 141 | } if ( src->get_qualifiers() < destAsRef->get_base()->get_qualifiers() ) { | 
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| [7ebaa56] | 142 | return Cost::safe; // cost needs to be higher than previous cast to differentiate adding qualifiers vs. keeping same | 
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| [89be1c68] | 143 | } else { | 
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|  | 144 | return Cost::unsafe; | 
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|  | 145 | } // if | 
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|  | 146 | } else if ( destAsRef->get_base()->get_const() ) { | 
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| [5ccb10d] | 147 | PRINT( std::cerr << "rvalue to const ref conversion" << std::endl; ) | 
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| [89be1c68] | 148 | // rvalue-to-const-reference conversion: T => const T & | 
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|  | 149 | return Cost::safe; | 
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|  | 150 | } else { | 
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| [5ccb10d] | 151 | PRINT( std::cerr << "rvalue to non-const reference conversion" << std::endl; ) | 
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| [89be1c68] | 152 | // rvalue-to-reference conversion: T => T & | 
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|  | 153 | return Cost::unsafe; | 
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|  | 154 | } // if | 
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|  | 155 | } // if | 
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| [5ccb10d] | 156 | PRINT( std::cerr << "attempting to convert from incompatible base type -- fail" << std::endl; ) | 
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| [2463d0e] | 157 | } | 
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|  | 158 | return Cost::infinity; | 
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|  | 159 | } | 
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|  | 160 |  | 
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| [0c6596f] | 161 | Cost convertToReferenceCost( Type * src, ReferenceType * dest, const SymTab::Indexer & indexer, const TypeEnvironment & env, PtrsFunction func ) { | 
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| [89be1c68] | 162 | int sdepth = src->referenceDepth(), ddepth = dest->referenceDepth(); | 
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| [0c6596f] | 163 | return convertToReferenceCost( src, dest, sdepth-ddepth, indexer, env, func ); | 
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| [89be1c68] | 164 | } | 
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|  | 165 |  | 
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| [a32b204] | 166 | ConversionCost::ConversionCost( Type *dest, const SymTab::Indexer &indexer, const TypeEnvironment &env ) | 
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|  | 167 | : dest( dest ), indexer( indexer ), cost( Cost::infinity ), env( env ) { | 
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|  | 168 | } | 
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| [51b73452] | 169 |  | 
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|  | 170 | /* | 
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| [a32b204] | 171 | Old | 
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|  | 172 | === | 
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|  | 173 | Double | 
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|  | 174 | | | 
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|  | 175 | Float | 
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|  | 176 | | | 
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|  | 177 | ULong | 
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|  | 178 | /   \ | 
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|  | 179 | UInt    Long | 
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|  | 180 | \   / | 
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|  | 181 | Int | 
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|  | 182 | | | 
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|  | 183 | Ushort | 
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|  | 184 | | | 
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|  | 185 | Short | 
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|  | 186 | | | 
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|  | 187 | Uchar | 
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|  | 188 | /   \ | 
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|  | 189 | Schar   Char | 
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|  | 190 |  | 
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|  | 191 | New | 
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|  | 192 | === | 
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|  | 193 | +-----LongDoubleComplex--+ | 
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|  | 194 | LongDouble--+          |             +-LongDoubleImag | 
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|  | 195 | |         +---DoubleComplex---+         | | 
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|  | 196 | Double------+        |          +----DoubleImag | 
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|  | 197 | |           +-FloatComplex-+            | | 
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|  | 198 | Float---------+              +-------FloatImag | 
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|  | 199 | | | 
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|  | 200 | ULongLong | 
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|  | 201 | | | 
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|  | 202 | LongLong | 
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|  | 203 | | | 
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|  | 204 | ULong | 
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|  | 205 | /   \ | 
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|  | 206 | UInt    Long | 
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|  | 207 | \   / | 
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|  | 208 | Int | 
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|  | 209 | | | 
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|  | 210 | Ushort | 
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|  | 211 | | | 
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|  | 212 | Short | 
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|  | 213 | | | 
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|  | 214 | Uchar | 
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|  | 215 | /   \ | 
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|  | 216 | Schar   Char | 
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|  | 217 | \   / | 
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|  | 218 | Bool | 
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| [51b73452] | 219 | */ | 
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|  | 220 |  | 
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| [201aeb9] | 221 | static const int costMatrix[ BasicType::NUMBER_OF_BASIC_TYPES ][ BasicType::NUMBER_OF_BASIC_TYPES ] = { | 
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|  | 222 | /* Src \ Dest:  Bool    Char    SChar   UChar   Short   UShort  Int     UInt    Long    ULong   LLong   ULLong  Float   Double  LDbl    FCplex  DCplex  LDCplex FImag   DImag   LDImag  I128,   U128 */ | 
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|  | 223 | /* Bool */      { 0,    1,              1,              2,              3,              4,              5,              6,              6,              7,              8,              9,              12,             13,             14,             12,             13,             14,             -1,             -1,             -1,             10,             11,     }, | 
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|  | 224 | /* Char */      { -1,   0,              -1,             1,              2,              3,              4,              5,              5,              6,              7,              8,              11,             12,             13,             11,             12,             13,             -1,             -1,             -1,             9,              10,     }, | 
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|  | 225 | /* SChar */ { -1,       -1,             0,              1,              2,              3,              4,              5,              5,              6,              7,              8,              11,             12,             13,             11,             12,             13,             -1,             -1,             -1,             9,              10,     }, | 
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|  | 226 | /* UChar */ { -1,       -1,             -1,             0,              1,              2,              3,              4,              4,              5,              6,              7,              10,             11,             12,             10,             11,             12,             -1,             -1,             -1,             8,              9,      }, | 
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|  | 227 | /* Short */ { -1,       -1,             -1,             -1,             0,              1,              2,              3,              3,              4,              5,              6,              9,              10,             11,             9,              10,             11,             -1,             -1,             -1,             7,              8,      }, | 
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|  | 228 | /* UShort */{ -1,       -1,             -1,             -1,             -1,             0,              1,              2,              2,              3,              4,              5,              8,              9,              10,             8,              9,              10,             -1,             -1,             -1,             6,              7,      }, | 
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|  | 229 | /* Int */       { -1,   -1,             -1,             -1,             -1,             -1,             0,              1,              1,              2,              3,              4,              7,              8,              9,              7,              8,              9,              -1,             -1,             -1,             5,              6,      }, | 
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|  | 230 | /* UInt */      { -1,   -1,             -1,             -1,             -1,             -1,             -1,             0,              -1,             1,              2,              3,              6,              7,              8,              6,              7,              8,              -1,             -1,             -1,             4,              5,      }, | 
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|  | 231 | /* Long */      { -1,   -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              2,              3,              6,              7,              8,              6,              7,              8,              -1,             -1,             -1,             4,              5,      }, | 
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|  | 232 | /* ULong */ { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              2,              5,              6,              7,              5,              6,              7,              -1,             -1,             -1,             3,              4,      }, | 
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|  | 233 | /* LLong */ { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              4,              5,              6,              4,              5,              6,              -1,             -1,             -1,             2,              3,      }, | 
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|  | 234 | /* ULLong */{ -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              3,              4,              5,              3,              4,              5,              -1,             -1,             -1,             1,              2,      }, | 
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|  | 235 |  | 
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|  | 236 | /* Float */ { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              2,              1,              2,              3,              -1,             -1,             -1,             -1,             -1,     }, | 
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|  | 237 | /* Double */{ -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              -1,             1,              2,              -1,             -1,             -1,             -1,             -1,     }, | 
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|  | 238 | /* LDbl */      { -1,   -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              -1,             -1,             1,              -1,             -1,             -1,             -1,             -1,     }, | 
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|  | 239 | /* FCplex */{ -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              2,              -1,             -1,             -1,             -1,             -1,     }, | 
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|  | 240 | /* DCplex */{ -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              1,              -1,             -1,             -1,             -1,             -1,     }, | 
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|  | 241 | /* LDCplex */{ -1,      -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             0,              -1,             -1,             -1,             -1,             -1,     }, | 
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|  | 242 | /* FImag */ { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             1,              2,              3,              0,              1,              2,              -1,             -1,     }, | 
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|  | 243 | /* DImag */ { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             1,              2,              -1,             0,              1,              -1,             -1,     }, | 
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|  | 244 | /* LDImag */{ -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             1,              -1,             -1,             0,              -1,             -1,     }, | 
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|  | 245 |  | 
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|  | 246 | /* I128 */  { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             2,              3,              4,              3,              4,              5,              -1,             -1,             -1,             0,              1,      }, | 
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|  | 247 | /* U128 */  { -1,       -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             -1,             1,              2,              3,              2,              3,              4,              -1,             -1,             -1,             -1,             0,      }, | 
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| [a32b204] | 248 | }; | 
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|  | 249 |  | 
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| [7e003011] | 250 | void ConversionCost::visit( __attribute((unused)) VoidType *voidType ) { | 
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| [a32b204] | 251 | cost = Cost::infinity; | 
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|  | 252 | } | 
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|  | 253 |  | 
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|  | 254 | void ConversionCost::visit(BasicType *basicType) { | 
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|  | 255 | if ( BasicType *destAsBasic = dynamic_cast< BasicType* >( dest ) ) { | 
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|  | 256 | int tableResult = costMatrix[ basicType->get_kind() ][ destAsBasic->get_kind() ]; | 
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|  | 257 | if ( tableResult == -1 ) { | 
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| [89be1c68] | 258 | cost = Cost::unsafe; | 
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| [a32b204] | 259 | } else { | 
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| [89be1c68] | 260 | cost = Cost::zero; | 
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|  | 261 | cost.incSafe( tableResult ); | 
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| [a32b204] | 262 | } // if | 
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| [a436947] | 263 | } else if ( dynamic_cast< EnumInstType *>( dest ) ) { | 
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|  | 264 | // xxx - not positive this is correct, but appears to allow casting int => enum | 
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| [89be1c68] | 265 | cost = Cost::unsafe; | 
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| [89e6ffc] | 266 | } else if ( dynamic_cast< ZeroType* >( dest ) != nullptr || dynamic_cast< OneType* >( dest ) != nullptr ) { | 
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| [89be1c68] | 267 | cost = Cost::unsafe; | 
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| [89e6ffc] | 268 | } // if | 
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| [a32b204] | 269 | } | 
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|  | 270 |  | 
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|  | 271 | void ConversionCost::visit(PointerType *pointerType) { | 
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|  | 272 | if ( PointerType *destAsPtr = dynamic_cast< PointerType* >( dest ) ) { | 
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| [5ccb10d] | 273 | PRINT( std::cerr << pointerType << " ===> " << destAsPtr; ) | 
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| [cb43451] | 274 | Type::Qualifiers tq1 = pointerType->get_base()->get_qualifiers(); | 
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|  | 275 | Type::Qualifiers tq2 = destAsPtr->get_base()->get_qualifiers(); | 
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|  | 276 | if ( tq1 <= tq2 && typesCompatibleIgnoreQualifiers( pointerType->get_base(), destAsPtr->get_base(), indexer, env ) ) { | 
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|  | 277 | if ( tq1 == tq2 ) { | 
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|  | 278 | // types are the same | 
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|  | 279 | cost = Cost::zero; | 
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|  | 280 | } else { | 
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|  | 281 | // types are the same, except otherPointer has more qualifiers | 
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| [5ccb10d] | 282 | PRINT( std::cerr << " :: compatible and good qualifiers" << std::endl; ) | 
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| [cb43451] | 283 | cost = Cost::safe; | 
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|  | 284 | } | 
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|  | 285 | } else {  // xxx - this discards qualifiers from consideration -- reducing qualifiers is a safe conversion; is this right? | 
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| [a32b204] | 286 | int assignResult = ptrsAssignable( pointerType->get_base(), destAsPtr->get_base(), env ); | 
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| [5ccb10d] | 287 | PRINT( std::cerr << " :: " << assignResult << std::endl; ) | 
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| [cb43451] | 288 | if ( assignResult < 0 && pointerType->get_base()->get_qualifiers() <= destAsPtr->get_qualifiers() ) { | 
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| [89be1c68] | 289 | cost = Cost::safe; | 
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| [a32b204] | 290 | } else if ( assignResult > 0 ) { | 
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| [89be1c68] | 291 | cost = Cost::unsafe; | 
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| [a32b204] | 292 | } // if | 
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| [cb43451] | 293 | // assignResult == 0 means Cost::Infinity | 
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| [a32b204] | 294 | } // if | 
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| [89e6ffc] | 295 | } else if ( dynamic_cast< ZeroType* >( dest ) != nullptr || dynamic_cast< OneType* >( dest ) != nullptr ) { | 
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| [89be1c68] | 296 | cost = Cost::unsafe; | 
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| [a32b204] | 297 | } // if | 
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|  | 298 | } | 
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|  | 299 |  | 
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| [7e003011] | 300 | void ConversionCost::visit(__attribute((unused)) ArrayType *arrayType) {} | 
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| [2463d0e] | 301 |  | 
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|  | 302 | void ConversionCost::visit(ReferenceType *refType) { | 
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|  | 303 | // Note: dest can never be a reference, since it would have been caught in an earlier check | 
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|  | 304 | assert( ! dynamic_cast< ReferenceType * >( dest ) ); | 
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|  | 305 | // convert reference to rvalue: cv T1 & => T2 | 
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|  | 306 | // recursively compute conversion cost from T1 to T2. | 
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|  | 307 | // cv can be safely dropped because of 'implicit dereference' behavior. | 
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| [150ec33] | 308 | refType->base->accept( *this ); | 
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|  | 309 | if ( refType->base->get_qualifiers() == dest->get_qualifiers() ) { | 
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| [cb43451] | 310 | cost.incReference();  // prefer exact qualifiers | 
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| [150ec33] | 311 | } else if ( refType->base->get_qualifiers() < dest->get_qualifiers() ) { | 
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| [cb43451] | 312 | cost.incSafe(); // then gaining qualifiers | 
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|  | 313 | } else { | 
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|  | 314 | cost.incUnsafe(); // lose qualifiers as last resort | 
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|  | 315 | } | 
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| [5ccb10d] | 316 | PRINT( std::cerr << refType << " ==> " << dest << " " << cost << std::endl; ) | 
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| [2463d0e] | 317 | } | 
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|  | 318 |  | 
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| [7e003011] | 319 | void ConversionCost::visit(__attribute((unused)) FunctionType *functionType) {} | 
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| [a32b204] | 320 |  | 
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|  | 321 | void ConversionCost::visit(StructInstType *inst) { | 
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|  | 322 | if ( StructInstType *destAsInst = dynamic_cast< StructInstType* >( dest ) ) { | 
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| [150ec33] | 323 | if ( inst->name == destAsInst->name ) { | 
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| [a32b204] | 324 | cost = Cost::zero; | 
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|  | 325 | } // if | 
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|  | 326 | } // if | 
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|  | 327 | } | 
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|  | 328 |  | 
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|  | 329 | void ConversionCost::visit(UnionInstType *inst) { | 
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| [150ec33] | 330 | if ( UnionInstType *destAsInst = dynamic_cast< UnionInstType* >( dest ) ) { | 
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|  | 331 | if ( inst->name == destAsInst->name ) { | 
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| [a32b204] | 332 | cost = Cost::zero; | 
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|  | 333 | } // if | 
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|  | 334 | } // if | 
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|  | 335 | } | 
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|  | 336 |  | 
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| [7e003011] | 337 | void ConversionCost::visit( __attribute((unused)) EnumInstType *inst ) { | 
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| [a32b204] | 338 | static Type::Qualifiers q; | 
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|  | 339 | static BasicType integer( q, BasicType::SignedInt ); | 
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| [2463d0e] | 340 | integer.accept( *this );  // safe if dest >= int | 
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| [89be1c68] | 341 | if ( cost < Cost::unsafe ) { | 
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| [a32b204] | 342 | cost.incSafe(); | 
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|  | 343 | } // if | 
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|  | 344 | } | 
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|  | 345 |  | 
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| [7e003011] | 346 | void ConversionCost::visit( __attribute((unused)) TraitInstType *inst) { | 
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| [a32b204] | 347 | } | 
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|  | 348 |  | 
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|  | 349 | void ConversionCost::visit(TypeInstType *inst) { | 
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|  | 350 | EqvClass eqvClass; | 
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|  | 351 | NamedTypeDecl *namedType; | 
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|  | 352 | if ( env.lookup( inst->get_name(), eqvClass ) ) { | 
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|  | 353 | cost = conversionCost( eqvClass.type, dest, indexer, env ); | 
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|  | 354 | } else if ( TypeInstType *destAsInst = dynamic_cast< TypeInstType* >( dest ) ) { | 
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|  | 355 | if ( inst->get_name() == destAsInst->get_name() ) { | 
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|  | 356 | cost = Cost::zero; | 
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|  | 357 | } | 
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|  | 358 | } else if ( ( namedType = indexer.lookupType( inst->get_name() ) ) ) { | 
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|  | 359 | TypeDecl *type = dynamic_cast< TypeDecl* >( namedType ); | 
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|  | 360 | // all typedefs should be gone by this point | 
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|  | 361 | assert( type ); | 
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|  | 362 | if ( type->get_base() ) { | 
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| [89be1c68] | 363 | cost = conversionCost( type->get_base(), dest, indexer, env ) + Cost::safe; | 
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| [a32b204] | 364 | } // if | 
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|  | 365 | } // if | 
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|  | 366 | } | 
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|  | 367 |  | 
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| [7e003011] | 368 | void ConversionCost::visit( __attribute((unused)) TupleType *tupleType) { | 
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| [89be1c68] | 369 | Cost c = Cost::zero; | 
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| [a32b204] | 370 | if ( TupleType *destAsTuple = dynamic_cast< TupleType* >( dest ) ) { | 
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|  | 371 | std::list< Type* >::const_iterator srcIt = tupleType->get_types().begin(); | 
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|  | 372 | std::list< Type* >::const_iterator destIt = destAsTuple->get_types().begin(); | 
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| [4ab9536] | 373 | while ( srcIt != tupleType->get_types().end() && destIt != destAsTuple->get_types().end() ) { | 
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| [a32b204] | 374 | Cost newCost = conversionCost( *srcIt++, *destIt++, indexer, env ); | 
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|  | 375 | if ( newCost == Cost::infinity ) { | 
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|  | 376 | return; | 
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|  | 377 | } // if | 
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|  | 378 | c += newCost; | 
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|  | 379 | } // while | 
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|  | 380 | if ( destIt != destAsTuple->get_types().end() ) { | 
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|  | 381 | cost = Cost::infinity; | 
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|  | 382 | } else { | 
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|  | 383 | cost = c; | 
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|  | 384 | } // if | 
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|  | 385 | } // if | 
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|  | 386 | } | 
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| [44b7088] | 387 |  | 
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| [7e003011] | 388 | void ConversionCost::visit( __attribute((unused)) VarArgsType *varArgsType) { | 
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| [90c3b1c] | 389 | if ( dynamic_cast< VarArgsType* >( dest ) ) { | 
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| [44b7088] | 390 | cost = Cost::zero; | 
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|  | 391 | } | 
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|  | 392 | } | 
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| [89e6ffc] | 393 |  | 
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| [7e003011] | 394 | void ConversionCost::visit( __attribute((unused)) ZeroType *zeroType) { | 
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| [89e6ffc] | 395 | if ( dynamic_cast< ZeroType* >( dest ) ) { | 
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|  | 396 | cost = Cost::zero; | 
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|  | 397 | } else if ( BasicType *destAsBasic = dynamic_cast< BasicType* >( dest ) ) { | 
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|  | 398 | // copied from visit(BasicType*) for signed int, but +1 for safe conversions | 
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|  | 399 | int tableResult = costMatrix[ BasicType::SignedInt ][ destAsBasic->get_kind() ]; | 
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|  | 400 | if ( tableResult == -1 ) { | 
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| [89be1c68] | 401 | cost = Cost::unsafe; | 
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| [89e6ffc] | 402 | } else { | 
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| [89be1c68] | 403 | cost = Cost::zero; | 
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|  | 404 | cost.incSafe( tableResult + 1 ); | 
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| [89e6ffc] | 405 | } | 
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|  | 406 | } else if ( dynamic_cast< PointerType* >( dest ) ) { | 
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| [89be1c68] | 407 | cost = Cost::safe; | 
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| [89e6ffc] | 408 | } | 
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|  | 409 | } | 
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|  | 410 |  | 
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| [7e003011] | 411 | void ConversionCost::visit( __attribute((unused)) OneType *oneType) { | 
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| [89e6ffc] | 412 | if ( dynamic_cast< OneType* >( dest ) ) { | 
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|  | 413 | cost = Cost::zero; | 
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|  | 414 | } else if ( BasicType *destAsBasic = dynamic_cast< BasicType* >( dest ) ) { | 
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|  | 415 | // copied from visit(BasicType*) for signed int, but +1 for safe conversions | 
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|  | 416 | int tableResult = costMatrix[ BasicType::SignedInt ][ destAsBasic->get_kind() ]; | 
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|  | 417 | if ( tableResult == -1 ) { | 
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| [89be1c68] | 418 | cost = Cost::unsafe; | 
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| [89e6ffc] | 419 | } else { | 
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| [89be1c68] | 420 | cost = Cost::zero; | 
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|  | 421 | cost.incSafe( tableResult + 1 ); | 
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| [89e6ffc] | 422 | } | 
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|  | 423 | } | 
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|  | 424 | } | 
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| [51b73452] | 425 | } // namespace ResolvExpr | 
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| [a32b204] | 426 |  | 
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|  | 427 | // Local Variables: // | 
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|  | 428 | // tab-width: 4 // | 
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|  | 429 | // mode: c++ // | 
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|  | 430 | // compile-command: "make install" // | 
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|  | 431 | // End: // | 
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