[51587aa] | 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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[906e24d] | 7 | // Lvalue.cc -- |
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[51587aa] | 8 | // |
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| 9 | // Author : Richard C. Bilson |
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| 10 | // Created On : Mon May 18 07:44:20 2015 |
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[01aeade] | 11 | // Last Modified By : Peter A. Buhr |
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[615a096] | 12 | // Last Modified On : Fri Mar 17 09:11:18 2017 |
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| 13 | // Update Count : 5 |
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[51587aa] | 14 | // |
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[51b7345] | 15 | |
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[e3e16bc] | 16 | #include <cassert> // for strict_dynamic_cast |
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[08fc48f] | 17 | #include <string> // for string |
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[51b7345] | 18 | |
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[8135d4c] | 19 | #include "Common/PassVisitor.h" |
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[08fc48f] | 20 | #include "GenPoly.h" // for isPolyType |
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[51b7345] | 21 | #include "Lvalue.h" |
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| 22 | |
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[08fc48f] | 23 | #include "Parser/LinkageSpec.h" // for Spec, isBuiltin, Intrinsic |
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| 24 | #include "ResolvExpr/TypeEnvironment.h" // for AssertionSet, OpenVarSet |
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| 25 | #include "ResolvExpr/Unify.h" // for unify |
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[51b7345] | 26 | #include "ResolvExpr/typeops.h" |
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[8135d4c] | 27 | #include "SymTab/Autogen.h" |
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[08fc48f] | 28 | #include "SymTab/Indexer.h" // for Indexer |
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| 29 | #include "SynTree/Declaration.h" // for Declaration, FunctionDecl |
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| 30 | #include "SynTree/Expression.h" // for Expression, ConditionalExpr |
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| 31 | #include "SynTree/Mutator.h" // for mutateAll, Mutator |
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| 32 | #include "SynTree/Statement.h" // for ReturnStmt, Statement (ptr o... |
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| 33 | #include "SynTree/Type.h" // for PointerType, Type, FunctionType |
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| 34 | #include "SynTree/Visitor.h" // for Visitor, acceptAll |
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[1d776fd] | 35 | |
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[cb43451] | 36 | #if 0 |
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| 37 | #define PRINT(x) x |
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| 38 | #else |
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| 39 | #define PRINT(x) |
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| 40 | #endif |
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| 41 | |
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[51b7345] | 42 | namespace GenPoly { |
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[01aeade] | 43 | namespace { |
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[9a34b5a] | 44 | // TODO: fold this into the general createDeref function?? |
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| 45 | Expression * mkDeref( Expression * arg ) { |
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| 46 | if ( SymTab::dereferenceOperator ) { |
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| 47 | VariableExpr * deref = new VariableExpr( SymTab::dereferenceOperator ); |
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[0690350] | 48 | deref->result = new PointerType( Type::Qualifiers(), deref->result ); |
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| 49 | Type * base = InitTweak::getPointerBase( arg->result ); |
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| 50 | assertf( base, "expected pointer type in dereference (type was %s)", toString( arg->result ).c_str() ); |
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[9a34b5a] | 51 | ApplicationExpr * ret = new ApplicationExpr( deref, { arg } ); |
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[0690350] | 52 | delete ret->result; |
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| 53 | ret->result = base->clone(); |
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| 54 | ret->result->set_lvalue( true ); |
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[9a34b5a] | 55 | return ret; |
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| 56 | } else { |
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| 57 | return UntypedExpr::createDeref( arg ); |
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| 58 | } |
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| 59 | } |
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| 60 | |
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[1d776fd] | 61 | struct ReferenceConversions final { |
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| 62 | Expression * postmutate( CastExpr * castExpr ); |
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[8a6cf7e] | 63 | Expression * postmutate( AddressExpr * addrExpr ); |
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[01aeade] | 64 | }; |
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| 65 | |
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[1d776fd] | 66 | /// Intrinsic functions that take reference parameters don't REALLY take reference parameters -- their reference arguments must always be implicitly dereferenced. |
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| 67 | struct FixIntrinsicArgs final { |
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[8499c707] | 68 | Expression * postmutate( ApplicationExpr * appExpr ); |
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[1d776fd] | 69 | }; |
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| 70 | |
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[9aaac6e9] | 71 | struct FixIntrinsicResult final : public WithGuards { |
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[8499c707] | 72 | Expression * postmutate( ApplicationExpr * appExpr ); |
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[9aaac6e9] | 73 | void premutate( FunctionDecl * funcDecl ); |
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| 74 | bool inIntrinsic = false; |
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[8499c707] | 75 | }; |
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[1d776fd] | 76 | |
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| 77 | /// Replace reference types with pointer types |
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| 78 | struct ReferenceTypeElimination final { |
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| 79 | Type * postmutate( ReferenceType * refType ); |
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[01aeade] | 80 | }; |
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[b6fd751] | 81 | |
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| 82 | /// GCC-like Generalized Lvalues (which have since been removed from GCC) |
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| 83 | /// https://gcc.gnu.org/onlinedocs/gcc-3.4.6/gcc/Lvalues.html#Lvalues |
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| 84 | /// Replaces &(a,b) with (a, &b), &(a ? b : c) with (a ? &b : &c) |
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[d335627] | 85 | struct GeneralizedLvalue final : public WithVisitorRef<GeneralizedLvalue> { |
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[1d776fd] | 86 | Expression * postmutate( AddressExpr * addressExpr ); |
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[9236060] | 87 | Expression * postmutate( MemberExpr * memExpr ); |
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[acd7c5dd] | 88 | |
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| 89 | template<typename Func> |
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| 90 | Expression * applyTransformation( Expression * expr, Expression * arg, Func mkExpr ); |
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[b6fd751] | 91 | }; |
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[cb43451] | 92 | |
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| 93 | /// Removes redundant &*/*& pattern that this pass can generate |
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| 94 | struct CollapseAddrDeref final { |
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| 95 | Expression * postmutate( AddressExpr * addressExpr ); |
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| 96 | Expression * postmutate( ApplicationExpr * appExpr ); |
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| 97 | }; |
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[8499c707] | 98 | |
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| 99 | struct AddrRef final : public WithGuards { |
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| 100 | void premutate( AddressExpr * addrExpr ); |
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| 101 | Expression * postmutate( AddressExpr * addrExpr ); |
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| 102 | void premutate( Expression * expr ); |
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| 103 | |
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| 104 | bool first = true; |
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| 105 | bool current = false; |
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| 106 | int refDepth = 0; |
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| 107 | }; |
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[01aeade] | 108 | } // namespace |
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| 109 | |
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[b0440b7] | 110 | static bool referencesEliminated = false; |
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| 111 | // used by UntypedExpr::createDeref to determine whether result type of dereference should be ReferenceType or value type. |
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| 112 | bool referencesPermissable() { |
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| 113 | return ! referencesEliminated; |
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| 114 | } |
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| 115 | |
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[b1ccdfd] | 116 | void convertLvalue( std::list< Declaration* > & translationUnit ) { |
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[1d776fd] | 117 | PassVisitor<ReferenceConversions> refCvt; |
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| 118 | PassVisitor<ReferenceTypeElimination> elim; |
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| 119 | PassVisitor<GeneralizedLvalue> genLval; |
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| 120 | PassVisitor<FixIntrinsicArgs> fixer; |
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[cb43451] | 121 | PassVisitor<CollapseAddrDeref> collapser; |
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[8499c707] | 122 | PassVisitor<AddrRef> addrRef; |
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| 123 | PassVisitor<FixIntrinsicResult> intrinsicResults; |
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| 124 | mutateAll( translationUnit, intrinsicResults ); |
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| 125 | mutateAll( translationUnit, addrRef ); |
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[1d776fd] | 126 | mutateAll( translationUnit, refCvt ); |
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| 127 | mutateAll( translationUnit, fixer ); |
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[cb43451] | 128 | mutateAll( translationUnit, collapser ); |
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[8499c707] | 129 | mutateAll( translationUnit, genLval ); |
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[8a6cf7e] | 130 | mutateAll( translationUnit, elim ); // last because other passes need reference types to work |
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[b0440b7] | 131 | |
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| 132 | // from this point forward, no other pass should create reference types. |
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| 133 | referencesEliminated = true; |
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[01aeade] | 134 | } |
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| 135 | |
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[acd7c5dd] | 136 | Expression * generalizedLvalue( Expression * expr ) { |
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[9236060] | 137 | PassVisitor<GeneralizedLvalue> genLval; |
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[acd7c5dd] | 138 | return expr->acceptMutator( genLval ); |
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| 139 | } |
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| 140 | |
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[01aeade] | 141 | namespace { |
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[8a6cf7e] | 142 | // true for intrinsic function calls that return a reference |
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[1d776fd] | 143 | bool isIntrinsicReference( Expression * expr ) { |
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[8a6cf7e] | 144 | if ( UntypedExpr * untyped = dynamic_cast< UntypedExpr * >( expr ) ) { |
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| 145 | std::string fname = InitTweak::getFunctionName( untyped ); |
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| 146 | // known intrinsic-reference prelude functions |
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| 147 | return fname == "*?" || fname == "?[?]"; |
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[1d776fd] | 148 | } else if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * > ( expr ) ) { |
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| 149 | if ( DeclarationWithType * func = InitTweak::getFunction( appExpr ) ) { |
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[8a6cf7e] | 150 | // use type of return variable rather than expr result type, since it may have been changed to a pointer type |
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| 151 | FunctionType * ftype = GenPoly::getFunctionType( func->get_type() ); |
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[b1ccdfd] | 152 | Type * ret = ftype->returnVals.empty() ? nullptr : ftype->returnVals.front()->get_type(); |
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| 153 | return func->linkage == LinkageSpec::Intrinsic && dynamic_cast<ReferenceType *>( ret ); |
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[1d776fd] | 154 | } |
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[ce8c12f] | 155 | } |
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[1d776fd] | 156 | return false; |
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[ce8c12f] | 157 | } |
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| 158 | |
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[8499c707] | 159 | Expression * FixIntrinsicResult::postmutate( ApplicationExpr * appExpr ) { |
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| 160 | if ( isIntrinsicReference( appExpr ) ) { |
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| 161 | // eliminate reference types from intrinsic applications - now they return lvalues |
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[b1ccdfd] | 162 | Type * result = appExpr->result; |
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| 163 | appExpr->result = result->stripReferences()->clone(); |
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| 164 | appExpr->result->set_lvalue( true ); |
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[9aaac6e9] | 165 | if ( ! inIntrinsic ) { |
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| 166 | // when not in an intrinsic function, add a cast to |
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| 167 | // don't add cast when in an intrinsic function, since they already have the cast |
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| 168 | Expression * ret = new CastExpr( appExpr, result ); |
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[b1ccdfd] | 169 | std::swap( ret->env, appExpr->env ); |
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[9aaac6e9] | 170 | return ret; |
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| 171 | } |
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| 172 | delete result; |
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[8499c707] | 173 | } |
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| 174 | return appExpr; |
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| 175 | } |
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| 176 | |
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[9aaac6e9] | 177 | void FixIntrinsicResult::premutate( FunctionDecl * funcDecl ) { |
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| 178 | GuardValue( inIntrinsic ); |
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| 179 | inIntrinsic = funcDecl->linkage == LinkageSpec::Intrinsic; |
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| 180 | } |
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| 181 | |
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[1d776fd] | 182 | Expression * FixIntrinsicArgs::postmutate( ApplicationExpr * appExpr ) { |
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[9a34b5a] | 183 | // intrinsic functions don't really take reference-typed parameters, so they require an implicit dereference on their arguments. |
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[1d776fd] | 184 | if ( DeclarationWithType * function = InitTweak::getFunction( appExpr ) ) { |
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[d335627] | 185 | FunctionType * ftype = GenPoly::getFunctionType( function->get_type() ); |
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| 186 | assertf( ftype, "Function declaration does not have function type." ); |
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| 187 | // can be of differing lengths only when function is variadic |
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[b1ccdfd] | 188 | assertf( ftype->parameters.size() == appExpr->args.size() || ftype->isVarArgs, "ApplicationExpr args do not match formal parameter type." ); |
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[b0440b7] | 189 | |
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| 190 | |
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[d335627] | 191 | unsigned int i = 0; |
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[b1ccdfd] | 192 | const unsigned int end = ftype->parameters.size(); |
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| 193 | for ( auto p : unsafe_group_iterate( appExpr->args, ftype->parameters ) ) { |
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[d335627] | 194 | if (i == end) break; |
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| 195 | Expression *& arg = std::get<0>( p ); |
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| 196 | Type * formal = std::get<1>( p )->get_type(); |
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| 197 | PRINT( |
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| 198 | std::cerr << "pair<0>: " << arg << std::endl; |
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| 199 | std::cerr << "pair<1>: " << formal << std::endl; |
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| 200 | ) |
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| 201 | if ( dynamic_cast<ReferenceType*>( formal ) ) { |
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[8499c707] | 202 | if ( isIntrinsicReference( arg ) ) { // do not combine conditions, because that changes the meaning of the else if |
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[d335627] | 203 | if ( function->get_linkage() != LinkageSpec::Intrinsic ) { // intrinsic functions that turn pointers into references |
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| 204 | // if argument is dereference or array subscript, the result isn't REALLY a reference, so it's not necessary to fix the argument |
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[8499c707] | 205 | PRINT( |
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| 206 | std::cerr << "===is intrinsic arg in non-intrinsic call - adding address" << std::endl; |
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| 207 | ) |
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[d335627] | 208 | arg = new AddressExpr( arg ); |
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| 209 | } |
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| 210 | } else if ( function->get_linkage() == LinkageSpec::Intrinsic ) { |
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[8499c707] | 211 | // std::cerr << "===adding deref to arg" << std::endl; |
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[d335627] | 212 | // if the parameter is a reference, add a dereference to the reference-typed argument. |
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[b1ccdfd] | 213 | Type * baseType = InitTweak::getPointerBase( arg->result ); |
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| 214 | assertf( baseType, "parameter is reference, arg must be pointer or reference: %s", toString( arg->result ).c_str() ); |
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[d335627] | 215 | PointerType * ptrType = new PointerType( Type::Qualifiers(), baseType->clone() ); |
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[b1ccdfd] | 216 | delete arg->result; |
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[d335627] | 217 | arg->set_result( ptrType ); |
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| 218 | arg = mkDeref( arg ); |
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[1d776fd] | 219 | } |
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| 220 | } |
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[d335627] | 221 | ++i; |
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[baba5d8] | 222 | } |
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[1d776fd] | 223 | } |
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| 224 | return appExpr; |
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[01aeade] | 225 | } |
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| 226 | |
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[8499c707] | 227 | // idea: &&&E: get outer &, inner & |
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| 228 | // at inner &, record depth D of reference type |
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| 229 | // at outer &, add D derefs. |
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[8135d4c] | 230 | void AddrRef::premutate( Expression * ) { |
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[8499c707] | 231 | GuardValue( current ); |
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| 232 | GuardValue( first ); |
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| 233 | current = false; |
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| 234 | first = true; |
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| 235 | } |
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| 236 | |
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[8135d4c] | 237 | void AddrRef::premutate( AddressExpr * ) { |
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[8499c707] | 238 | GuardValue( current ); |
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| 239 | GuardValue( first ); |
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| 240 | current = first; |
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| 241 | first = false; |
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| 242 | if ( current ) { |
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| 243 | GuardValue( refDepth ); |
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| 244 | refDepth = 0; |
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| 245 | } |
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| 246 | } |
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| 247 | |
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| 248 | Expression * AddrRef::postmutate( AddressExpr * addrExpr ) { |
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| 249 | if ( refDepth == 0 ) { |
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[b1ccdfd] | 250 | if ( ! isIntrinsicReference( addrExpr->arg ) ) { |
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[8499c707] | 251 | // try to avoid ?[?] |
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[b1ccdfd] | 252 | refDepth = addrExpr->arg->result->referenceDepth(); |
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[8499c707] | 253 | } |
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| 254 | } |
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| 255 | if ( current ) { |
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| 256 | Expression * ret = addrExpr; |
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| 257 | while ( refDepth ) { |
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| 258 | ret = mkDeref( ret ); |
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| 259 | refDepth--; |
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| 260 | } |
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| 261 | return ret; |
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| 262 | } |
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| 263 | return addrExpr; |
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| 264 | } |
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| 265 | |
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[8a6cf7e] | 266 | Expression * ReferenceConversions::postmutate( AddressExpr * addrExpr ) { |
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| 267 | // Inner expression may have been lvalue to reference conversion, which becomes an address expression. |
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| 268 | // In this case, remove the outer address expression and return the argument. |
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| 269 | // TODO: It's possible that this might catch too much and require a more sophisticated check. |
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| 270 | return addrExpr; |
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| 271 | } |
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| 272 | |
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[1d776fd] | 273 | Expression * ReferenceConversions::postmutate( CastExpr * castExpr ) { |
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[9a34b5a] | 274 | // xxx - is it possible to convert directly between reference types with a different base? E.g., |
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| 275 | // int x; |
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| 276 | // (double&)x; |
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| 277 | // At the moment, I am working off of the assumption that this is illegal, thus the cast becomes redundant |
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| 278 | // after this pass, so trash the cast altogether. If that changes, care must be taken to insert the correct |
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| 279 | // pointer casts in the right places. |
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| 280 | |
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[1d776fd] | 281 | // conversion to reference type |
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[b1ccdfd] | 282 | if ( ReferenceType * refType = dynamic_cast< ReferenceType * >( castExpr->result ) ) { |
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[1d776fd] | 283 | (void)refType; |
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[b1ccdfd] | 284 | if ( ReferenceType * otherRef = dynamic_cast< ReferenceType * >( castExpr->arg->result ) ) { |
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[1d776fd] | 285 | // nothing to do if casting from reference to reference. |
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| 286 | (void)otherRef; |
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[cb43451] | 287 | PRINT( std::cerr << "convert reference to reference -- nop" << std::endl; ) |
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[b1ccdfd] | 288 | if ( isIntrinsicReference( castExpr->arg ) ) { |
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| 289 | Expression * callExpr = castExpr->arg; |
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[cb43451] | 290 | PRINT( |
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| 291 | std::cerr << "but arg is deref -- &" << std::endl; |
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| 292 | std::cerr << callExpr << std::endl; |
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| 293 | ) |
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[8499c707] | 294 | callExpr = new AddressExpr( callExpr ); // this doesn't work properly for multiple casts |
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[b1ccdfd] | 295 | delete callExpr->result; |
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[8499c707] | 296 | callExpr->set_result( refType->clone() ); |
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[1d776fd] | 297 | // move environment out to new top-level |
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[b1ccdfd] | 298 | callExpr->env = castExpr->env; |
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| 299 | castExpr->arg = nullptr; |
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| 300 | castExpr->env = nullptr; |
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[9a34b5a] | 301 | delete castExpr; |
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[1d776fd] | 302 | return callExpr; |
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| 303 | } |
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[8499c707] | 304 | int depth1 = refType->referenceDepth(); |
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| 305 | int depth2 = otherRef->referenceDepth(); |
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[fc56cdbf] | 306 | int diff = depth1-depth2; |
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| 307 | if ( diff == 0 ) { |
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[0690350] | 308 | // conversion between references of the same depth |
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[fc56cdbf] | 309 | assertf( depth1 == depth2, "non-intrinsic reference with cast of reference to reference not yet supported: %d %d %s", depth1, depth2, toString( castExpr ).c_str() ); |
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| 310 | PRINT( std::cerr << castExpr << std::endl; ) |
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| 311 | return castExpr; |
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| 312 | } else if ( diff < 0 ) { |
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[0690350] | 313 | // conversion from reference to reference with less depth (e.g. int && -> int &): add dereferences |
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| 314 | Expression * ret = castExpr->arg; |
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[fc56cdbf] | 315 | for ( int i = 0; i < diff; ++i ) { |
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| 316 | ret = mkDeref( ret ); |
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| 317 | } |
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[0690350] | 318 | ret->env = castExpr->env; |
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| 319 | delete ret->result; |
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| 320 | ret->result = castExpr->result; |
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[1a4bef3] | 321 | ret->result->set_lvalue( true ); // ensure result is lvalue |
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[0690350] | 322 | castExpr->env = nullptr; |
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| 323 | castExpr->arg = nullptr; |
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| 324 | castExpr->result = nullptr; |
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[fc56cdbf] | 325 | delete castExpr; |
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| 326 | return ret; |
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| 327 | } else if ( diff > 0 ) { |
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[0690350] | 328 | // conversion from reference to reference with more depth (e.g. int & -> int &&): add address-of |
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| 329 | Expression * ret = castExpr->arg; |
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[fc56cdbf] | 330 | for ( int i = 0; i < diff; ++i ) { |
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| 331 | ret = new AddressExpr( ret ); |
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| 332 | } |
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[0690350] | 333 | ret->env = castExpr->env; |
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| 334 | delete ret->result; |
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| 335 | ret->result = castExpr->result; |
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| 336 | castExpr->env = nullptr; |
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| 337 | castExpr->arg = nullptr; |
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| 338 | castExpr->result = nullptr; |
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[fc56cdbf] | 339 | delete castExpr; |
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| 340 | return ret; |
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| 341 | } |
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| 342 | |
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[8499c707] | 343 | assertf( depth1 == depth2, "non-intrinsic reference with cast of reference to reference not yet supported: %d %d %s", depth1, depth2, toString( castExpr ).c_str() ); |
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[cb43451] | 344 | PRINT( std::cerr << castExpr << std::endl; ) |
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[1d776fd] | 345 | return castExpr; |
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[0690350] | 346 | } else if ( castExpr->arg->result->get_lvalue() ) { |
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[1d776fd] | 347 | // conversion from lvalue to reference |
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| 348 | // xxx - keep cast, but turn into pointer cast?? |
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| 349 | // xxx - memory |
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[cb43451] | 350 | PRINT( |
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| 351 | std::cerr << "convert lvalue to reference -- &" << std::endl; |
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[0690350] | 352 | std::cerr << castExpr->arg << std::endl; |
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[cb43451] | 353 | ) |
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[0690350] | 354 | AddressExpr * ret = new AddressExpr( castExpr->arg ); |
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| 355 | if ( refType->base->get_qualifiers() != castExpr->arg->result->get_qualifiers() ) { |
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[cb43451] | 356 | // must keep cast if cast-to type is different from the actual type |
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[0690350] | 357 | castExpr->arg = ret; |
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[cb43451] | 358 | return castExpr; |
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| 359 | } |
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[0690350] | 360 | ret->env = castExpr->env; |
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| 361 | delete ret->result; |
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| 362 | ret->result = castExpr->result; |
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| 363 | castExpr->env = nullptr; |
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| 364 | castExpr->arg = nullptr; |
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| 365 | castExpr->result = nullptr; |
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[9a34b5a] | 366 | delete castExpr; |
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| 367 | return ret; |
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[01aeade] | 368 | } else { |
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[1d776fd] | 369 | // rvalue to reference conversion -- introduce temporary |
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| 370 | } |
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| 371 | assertf( false, "Only conversions to reference from lvalue are currently supported: %s", toString( castExpr ).c_str() ); |
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[0690350] | 372 | } else if ( ReferenceType * refType = dynamic_cast< ReferenceType * >( castExpr->arg->result ) ) { |
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[d335627] | 373 | (void)refType; |
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[9a34b5a] | 374 | // conversion from reference to rvalue |
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[8a6cf7e] | 375 | PRINT( |
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| 376 | std::cerr << "convert reference to rvalue -- *" << std::endl; |
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| 377 | std::cerr << "was = " << castExpr << std::endl; |
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| 378 | ) |
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[0690350] | 379 | Expression * ret = castExpr->arg; |
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| 380 | TypeSubstitution * env = castExpr->env; |
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[8a6cf7e] | 381 | castExpr->set_env( nullptr ); |
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[9191a8e] | 382 | if ( ! isIntrinsicReference( ret ) ) { |
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| 383 | // dereference if not already dereferenced |
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| 384 | ret = mkDeref( ret ); |
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| 385 | } |
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[0690350] | 386 | if ( ResolvExpr::typesCompatibleIgnoreQualifiers( castExpr->result, castExpr->arg->result->stripReferences(), SymTab::Indexer() ) ) { |
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[b0440b7] | 387 | // can remove cast if types are compatible, changing expression type to value type |
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[0690350] | 388 | ret->result = castExpr->result->clone(); |
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[1a4bef3] | 389 | ret->result->set_lvalue( true ); // ensure result is lvalue |
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[0690350] | 390 | castExpr->arg = nullptr; |
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[8a6cf7e] | 391 | delete castExpr; |
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| 392 | } else { |
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| 393 | // must keep cast if types are different |
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[0690350] | 394 | castExpr->arg = ret; |
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[8a6cf7e] | 395 | ret = castExpr; |
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| 396 | } |
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| 397 | ret->set_env( env ); |
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[9191a8e] | 398 | PRINT( std::cerr << "now: " << ret << std::endl; ) |
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| 399 | return ret; |
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[1d776fd] | 400 | } |
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| 401 | return castExpr; |
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[01aeade] | 402 | } |
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[b6fd751] | 403 | |
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[1d776fd] | 404 | Type * ReferenceTypeElimination::postmutate( ReferenceType * refType ) { |
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[b1ccdfd] | 405 | Type * base = refType->base; |
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[8a6cf7e] | 406 | Type::Qualifiers qualifiers = refType->get_qualifiers(); |
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[b1ccdfd] | 407 | refType->base = nullptr; |
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[1d776fd] | 408 | delete refType; |
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[8a6cf7e] | 409 | return new PointerType( qualifiers, base ); |
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[ce8c12f] | 410 | } |
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| 411 | |
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[acd7c5dd] | 412 | template<typename Func> |
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| 413 | Expression * GeneralizedLvalue::applyTransformation( Expression * expr, Expression * arg, Func mkExpr ) { |
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| 414 | if ( CommaExpr * commaExpr = dynamic_cast< CommaExpr * >( arg ) ) { |
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[b1ccdfd] | 415 | Expression * arg1 = commaExpr->arg1->clone(); |
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| 416 | Expression * arg2 = commaExpr->arg2->clone(); |
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[9236060] | 417 | Expression * ret = new CommaExpr( arg1, mkExpr( arg2 )->acceptMutator( *visitor ) ); |
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[b1ccdfd] | 418 | ret->env = expr->env; |
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| 419 | expr->env = nullptr; |
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[acd7c5dd] | 420 | delete expr; |
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[8499c707] | 421 | return ret; |
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[acd7c5dd] | 422 | } else if ( ConditionalExpr * condExpr = dynamic_cast< ConditionalExpr * >( arg ) ) { |
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[b1ccdfd] | 423 | Expression * arg1 = condExpr->arg1->clone(); |
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| 424 | Expression * arg2 = condExpr->arg2->clone(); |
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| 425 | Expression * arg3 = condExpr->arg3->clone(); |
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[9236060] | 426 | ConditionalExpr * ret = new ConditionalExpr( arg1, mkExpr( arg2 )->acceptMutator( *visitor ), mkExpr( arg3 )->acceptMutator( *visitor ) ); |
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[b1ccdfd] | 427 | ret->env = expr->env; |
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| 428 | expr->env = nullptr; |
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[acd7c5dd] | 429 | delete expr; |
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| 430 | |
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| 431 | // conditional expr type may not be either of the argument types, need to unify |
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| 432 | using namespace ResolvExpr; |
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| 433 | Type* commonType = nullptr; |
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| 434 | TypeEnvironment newEnv; |
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| 435 | AssertionSet needAssertions, haveAssertions; |
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| 436 | OpenVarSet openVars; |
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[b1ccdfd] | 437 | unify( ret->arg2->result, ret->arg3->result, newEnv, needAssertions, haveAssertions, openVars, SymTab::Indexer(), commonType ); |
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| 438 | ret->result = commonType ? commonType : ret->arg2->result->clone(); |
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[8499c707] | 439 | return ret; |
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[b6fd751] | 440 | } |
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[acd7c5dd] | 441 | return expr; |
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| 442 | } |
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| 443 | |
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[9236060] | 444 | Expression * GeneralizedLvalue::postmutate( MemberExpr * memExpr ) { |
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[b1ccdfd] | 445 | return applyTransformation( memExpr, memExpr->aggregate, [=]( Expression * aggr ) { return new MemberExpr( memExpr->member, aggr ); } ); |
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[acd7c5dd] | 446 | } |
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| 447 | |
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[9236060] | 448 | Expression * GeneralizedLvalue::postmutate( AddressExpr * addrExpr ) { |
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[b1ccdfd] | 449 | return applyTransformation( addrExpr, addrExpr->arg, []( Expression * arg ) { return new AddressExpr( arg ); } ); |
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[b6fd751] | 450 | } |
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[cb43451] | 451 | |
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[8499c707] | 452 | Expression * CollapseAddrDeref::postmutate( AddressExpr * addrExpr ) { |
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[b1ccdfd] | 453 | Expression * arg = addrExpr->arg; |
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[cb43451] | 454 | if ( isIntrinsicReference( arg ) ) { |
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| 455 | std::string fname = InitTweak::getFunctionName( arg ); |
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| 456 | if ( fname == "*?" ) { |
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| 457 | Expression *& arg0 = InitTweak::getCallArg( arg, 0 ); |
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| 458 | Expression * ret = arg0; |
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[b1ccdfd] | 459 | ret->set_env( addrExpr->env ); |
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[cb43451] | 460 | arg0 = nullptr; |
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[b1ccdfd] | 461 | addrExpr->env = nullptr; |
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[8499c707] | 462 | delete addrExpr; |
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[cb43451] | 463 | return ret; |
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| 464 | } |
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[bf7b6015] | 465 | } else if ( CastExpr * castExpr = dynamic_cast< CastExpr * > ( arg ) ) { |
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| 466 | // need to move cast to pointer type out a level since address of pointer |
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| 467 | // is not valid C code (can be introduced in prior passes, e.g., InstantiateGeneric) |
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| 468 | if ( InitTweak::getPointerBase( castExpr->result ) ) { |
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| 469 | addrExpr->arg = castExpr->arg; |
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| 470 | castExpr->arg = addrExpr; |
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| 471 | castExpr->result = new PointerType( Type::Qualifiers(), castExpr->result ); |
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| 472 | return castExpr; |
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| 473 | } |
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[cb43451] | 474 | } |
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[8499c707] | 475 | return addrExpr; |
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[cb43451] | 476 | } |
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| 477 | |
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| 478 | Expression * CollapseAddrDeref::postmutate( ApplicationExpr * appExpr ) { |
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| 479 | if ( isIntrinsicReference( appExpr ) ) { |
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| 480 | std::string fname = InitTweak::getFunctionName( appExpr ); |
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| 481 | if ( fname == "*?" ) { |
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| 482 | Expression * arg = InitTweak::getCallArg( appExpr, 0 ); |
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| 483 | // xxx - this isn't right, because it can remove casts that should be there... |
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| 484 | // while ( CastExpr * castExpr = dynamic_cast< CastExpr * >( arg ) ) { |
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| 485 | // arg = castExpr->get_arg(); |
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| 486 | // } |
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| 487 | if ( AddressExpr * addrExpr = dynamic_cast< AddressExpr * >( arg ) ) { |
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[b1ccdfd] | 488 | Expression * ret = addrExpr->arg; |
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| 489 | ret->env = appExpr->env; |
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| 490 | addrExpr->arg = nullptr; |
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| 491 | appExpr->env = nullptr; |
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[cb43451] | 492 | delete appExpr; |
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| 493 | return ret; |
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| 494 | } |
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| 495 | } |
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| 496 | } |
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| 497 | return appExpr; |
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| 498 | } |
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[01aeade] | 499 | } // namespace |
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[51b7345] | 500 | } // namespace GenPoly |
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[01aeade] | 501 | |
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[51587aa] | 502 | // Local Variables: // |
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| 503 | // tab-width: 4 // |
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| 504 | // mode: c++ // |
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| 505 | // compile-command: "make install" // |
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| 506 | // End: // |
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