[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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[31cb252] | 61 | struct ReferenceConversions final : public WithStmtsToAdd { |
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[1d776fd] | 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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[a4d188f] | 281 | // Note: reference depth difference is the determining factor in what code is run, rather than whether something is |
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| 282 | // reference type or not, since conversion still needs to occur when both types are references that differ in depth. |
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[31cb252] | 283 | |
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| 284 | Type * destType = castExpr->result; |
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| 285 | Type * srcType = castExpr->arg->result; |
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| 286 | int depth1 = destType->referenceDepth(); |
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| 287 | int depth2 = srcType->referenceDepth(); |
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| 288 | int diff = depth1 - depth2; |
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| 289 | |
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| 290 | if ( diff > 0 && ! srcType->get_lvalue() ) { |
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| 291 | // rvalue to reference conversion -- introduce temporary |
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| 292 | // know that reference depth of cast argument is 0, need to introduce n temporaries for reference depth of n, e.g. |
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| 293 | // (int &&&)3; |
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| 294 | // becomes |
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| 295 | // int __ref_tmp_0 = 3; |
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| 296 | // int & __ref_tmp_1 = _&_ref_tmp_0; |
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| 297 | // int && __ref_tmp_2 = &__ref_tmp_1; |
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| 298 | // &__ref_tmp_2; |
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[453b586] | 299 | // the last & comes from the remaining reference conversion code |
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[2348881] | 300 | SemanticWarning( castExpr->arg->location, Warning::RvalueToReferenceConversion, toCString( castExpr->arg ) ); |
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[31cb252] | 301 | |
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| 302 | static UniqueName tempNamer( "__ref_tmp_" ); |
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| 303 | ObjectDecl * temp = ObjectDecl::newObject( tempNamer.newName(), castExpr->arg->result->clone(), new SingleInit( castExpr->arg ) ); |
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| 304 | PRINT( std::cerr << "made temp: " << temp << std::endl; ) |
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| 305 | stmtsToAddBefore.push_back( new DeclStmt( temp ) ); |
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[a4d188f] | 306 | for ( int i = 0; i < depth1-1; i++ ) { // xxx - maybe this should be diff-1? check how this works with reference type for srcType |
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[31cb252] | 307 | ObjectDecl * newTemp = ObjectDecl::newObject( tempNamer.newName(), new ReferenceType( Type::Qualifiers(), temp->type->clone() ), new SingleInit( new AddressExpr( new VariableExpr( temp ) ) ) ); |
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| 308 | PRINT( std::cerr << "made temp" << i << ": " << newTemp << std::endl; ) |
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| 309 | stmtsToAddBefore.push_back( new DeclStmt( newTemp ) ); |
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| 310 | temp = newTemp; |
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| 311 | } |
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| 312 | // update diff so that remaining code works out correctly |
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| 313 | castExpr->arg = new VariableExpr( temp ); |
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| 314 | PRINT( std::cerr << "update cast to: " << castExpr << std::endl; ) |
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| 315 | srcType = castExpr->arg->result; |
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| 316 | depth2 = srcType->referenceDepth(); |
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| 317 | diff = depth1 - depth2; |
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| 318 | assert( diff == 1 ); |
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| 319 | } |
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[fc56cdbf] | 320 | |
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[a4d188f] | 321 | // handle conversion between different depths |
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[31cb252] | 322 | PRINT ( |
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| 323 | if ( depth1 || depth2 ) { |
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| 324 | std::cerr << "destType: " << destType << " / srcType: " << srcType << std::endl; |
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| 325 | std::cerr << "depth: " << depth1 << " / " << depth2 << std::endl; |
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| 326 | } |
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| 327 | ) |
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| 328 | if ( diff > 0 ) { |
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| 329 | // conversion to type with more depth (e.g. int & -> int &&): add address-of for each level of difference |
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| 330 | Expression * ret = castExpr->arg; |
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| 331 | for ( int i = 0; i < diff; ++i ) { |
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| 332 | ret = new AddressExpr( ret ); |
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| 333 | } |
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| 334 | if ( srcType->get_lvalue() && srcType->get_qualifiers() != strict_dynamic_cast<ReferenceType *>( destType )->base->get_qualifiers() ) { |
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| 335 | // must keep cast if cast-to type is different from the actual type |
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| 336 | castExpr->arg = ret; |
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[1d776fd] | 337 | return castExpr; |
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| 338 | } |
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[31cb252] | 339 | ret->env = castExpr->env; |
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| 340 | delete ret->result; |
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| 341 | ret->result = castExpr->result; |
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| 342 | castExpr->env = nullptr; |
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| 343 | castExpr->arg = nullptr; |
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| 344 | castExpr->result = nullptr; |
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| 345 | delete castExpr; |
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| 346 | return ret; |
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| 347 | } else if ( diff < 0 ) { |
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| 348 | // conversion to type with less depth (e.g. int && -> int &): add dereferences for each level of difference |
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| 349 | diff = -diff; // care only about magnitude now |
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[0690350] | 350 | Expression * ret = castExpr->arg; |
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[31cb252] | 351 | for ( int i = 0; i < diff; ++i ) { |
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[9191a8e] | 352 | ret = mkDeref( ret ); |
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| 353 | } |
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[31cb252] | 354 | if ( ! ResolvExpr::typesCompatibleIgnoreQualifiers( destType->stripReferences(), srcType->stripReferences(), SymTab::Indexer() ) ) { |
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[8a6cf7e] | 355 | // must keep cast if types are different |
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[0690350] | 356 | castExpr->arg = ret; |
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[31cb252] | 357 | return castExpr; |
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[8a6cf7e] | 358 | } |
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[31cb252] | 359 | ret->env = castExpr->env; |
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| 360 | delete ret->result; |
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| 361 | ret->result = castExpr->result; |
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| 362 | ret->result->set_lvalue( true ); // ensure result is lvalue |
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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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| 366 | delete castExpr; |
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[9191a8e] | 367 | return ret; |
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[31cb252] | 368 | } else { |
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| 369 | assert( diff == 0 ); |
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| 370 | // conversion between references of the same depth |
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| 371 | return castExpr; |
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[1d776fd] | 372 | } |
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[01aeade] | 373 | } |
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[b6fd751] | 374 | |
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[1d776fd] | 375 | Type * ReferenceTypeElimination::postmutate( ReferenceType * refType ) { |
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[b1ccdfd] | 376 | Type * base = refType->base; |
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[8a6cf7e] | 377 | Type::Qualifiers qualifiers = refType->get_qualifiers(); |
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[b1ccdfd] | 378 | refType->base = nullptr; |
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[1d776fd] | 379 | delete refType; |
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[8a6cf7e] | 380 | return new PointerType( qualifiers, base ); |
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[ce8c12f] | 381 | } |
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| 382 | |
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[acd7c5dd] | 383 | template<typename Func> |
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| 384 | Expression * GeneralizedLvalue::applyTransformation( Expression * expr, Expression * arg, Func mkExpr ) { |
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| 385 | if ( CommaExpr * commaExpr = dynamic_cast< CommaExpr * >( arg ) ) { |
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[b1ccdfd] | 386 | Expression * arg1 = commaExpr->arg1->clone(); |
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| 387 | Expression * arg2 = commaExpr->arg2->clone(); |
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[9236060] | 388 | Expression * ret = new CommaExpr( arg1, mkExpr( arg2 )->acceptMutator( *visitor ) ); |
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[b1ccdfd] | 389 | ret->env = expr->env; |
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| 390 | expr->env = nullptr; |
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[acd7c5dd] | 391 | delete expr; |
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[8499c707] | 392 | return ret; |
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[acd7c5dd] | 393 | } else if ( ConditionalExpr * condExpr = dynamic_cast< ConditionalExpr * >( arg ) ) { |
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[b1ccdfd] | 394 | Expression * arg1 = condExpr->arg1->clone(); |
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| 395 | Expression * arg2 = condExpr->arg2->clone(); |
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| 396 | Expression * arg3 = condExpr->arg3->clone(); |
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[9236060] | 397 | ConditionalExpr * ret = new ConditionalExpr( arg1, mkExpr( arg2 )->acceptMutator( *visitor ), mkExpr( arg3 )->acceptMutator( *visitor ) ); |
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[b1ccdfd] | 398 | ret->env = expr->env; |
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| 399 | expr->env = nullptr; |
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[acd7c5dd] | 400 | delete expr; |
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| 401 | |
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| 402 | // conditional expr type may not be either of the argument types, need to unify |
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| 403 | using namespace ResolvExpr; |
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| 404 | Type* commonType = nullptr; |
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| 405 | TypeEnvironment newEnv; |
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| 406 | AssertionSet needAssertions, haveAssertions; |
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| 407 | OpenVarSet openVars; |
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[b1ccdfd] | 408 | unify( ret->arg2->result, ret->arg3->result, newEnv, needAssertions, haveAssertions, openVars, SymTab::Indexer(), commonType ); |
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| 409 | ret->result = commonType ? commonType : ret->arg2->result->clone(); |
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[8499c707] | 410 | return ret; |
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[b6fd751] | 411 | } |
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[acd7c5dd] | 412 | return expr; |
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| 413 | } |
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| 414 | |
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[9236060] | 415 | Expression * GeneralizedLvalue::postmutate( MemberExpr * memExpr ) { |
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[b1ccdfd] | 416 | return applyTransformation( memExpr, memExpr->aggregate, [=]( Expression * aggr ) { return new MemberExpr( memExpr->member, aggr ); } ); |
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[acd7c5dd] | 417 | } |
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| 418 | |
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[9236060] | 419 | Expression * GeneralizedLvalue::postmutate( AddressExpr * addrExpr ) { |
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[b1ccdfd] | 420 | return applyTransformation( addrExpr, addrExpr->arg, []( Expression * arg ) { return new AddressExpr( arg ); } ); |
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[b6fd751] | 421 | } |
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[cb43451] | 422 | |
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[8499c707] | 423 | Expression * CollapseAddrDeref::postmutate( AddressExpr * addrExpr ) { |
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[b1ccdfd] | 424 | Expression * arg = addrExpr->arg; |
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[cb43451] | 425 | if ( isIntrinsicReference( arg ) ) { |
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| 426 | std::string fname = InitTweak::getFunctionName( arg ); |
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| 427 | if ( fname == "*?" ) { |
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| 428 | Expression *& arg0 = InitTweak::getCallArg( arg, 0 ); |
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| 429 | Expression * ret = arg0; |
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[b1ccdfd] | 430 | ret->set_env( addrExpr->env ); |
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[cb43451] | 431 | arg0 = nullptr; |
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[b1ccdfd] | 432 | addrExpr->env = nullptr; |
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[8499c707] | 433 | delete addrExpr; |
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[cb43451] | 434 | return ret; |
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| 435 | } |
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[bf7b6015] | 436 | } else if ( CastExpr * castExpr = dynamic_cast< CastExpr * > ( arg ) ) { |
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| 437 | // need to move cast to pointer type out a level since address of pointer |
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| 438 | // is not valid C code (can be introduced in prior passes, e.g., InstantiateGeneric) |
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| 439 | if ( InitTweak::getPointerBase( castExpr->result ) ) { |
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| 440 | addrExpr->arg = castExpr->arg; |
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| 441 | castExpr->arg = addrExpr; |
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| 442 | castExpr->result = new PointerType( Type::Qualifiers(), castExpr->result ); |
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| 443 | return castExpr; |
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| 444 | } |
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[cb43451] | 445 | } |
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[8499c707] | 446 | return addrExpr; |
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[cb43451] | 447 | } |
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| 448 | |
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| 449 | Expression * CollapseAddrDeref::postmutate( ApplicationExpr * appExpr ) { |
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| 450 | if ( isIntrinsicReference( appExpr ) ) { |
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| 451 | std::string fname = InitTweak::getFunctionName( appExpr ); |
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| 452 | if ( fname == "*?" ) { |
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| 453 | Expression * arg = InitTweak::getCallArg( appExpr, 0 ); |
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| 454 | // xxx - this isn't right, because it can remove casts that should be there... |
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| 455 | // while ( CastExpr * castExpr = dynamic_cast< CastExpr * >( arg ) ) { |
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| 456 | // arg = castExpr->get_arg(); |
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| 457 | // } |
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| 458 | if ( AddressExpr * addrExpr = dynamic_cast< AddressExpr * >( arg ) ) { |
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[b1ccdfd] | 459 | Expression * ret = addrExpr->arg; |
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| 460 | ret->env = appExpr->env; |
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| 461 | addrExpr->arg = nullptr; |
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| 462 | appExpr->env = nullptr; |
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[cb43451] | 463 | delete appExpr; |
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| 464 | return ret; |
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| 465 | } |
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| 466 | } |
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| 467 | } |
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| 468 | return appExpr; |
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| 469 | } |
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[01aeade] | 470 | } // namespace |
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[51b7345] | 471 | } // namespace GenPoly |
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[01aeade] | 472 | |
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[51587aa] | 473 | // Local Variables: // |
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| 474 | // tab-width: 4 // |
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| 475 | // mode: c++ // |
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| 476 | // compile-command: "make install" // |
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| 477 | // End: // |
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