[0dd3a2f] | 1 | // |
---|
| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo |
---|
| 3 | // |
---|
| 4 | // The contents of this file are covered under the licence agreement in the |
---|
| 5 | // file "LICENCE" distributed with Cforall. |
---|
| 6 | // |
---|
[5382492] | 7 | // TypeSubstitution.cc -- |
---|
[0dd3a2f] | 8 | // |
---|
| 9 | // Author : Richard C. Bilson |
---|
| 10 | // Created On : Mon May 18 07:44:20 2015 |
---|
[6f95000] | 11 | // Last Modified By : Peter A. Buhr |
---|
| 12 | // Last Modified On : Thu Mar 16 15:54:35 2017 |
---|
| 13 | // Update Count : 4 |
---|
[0dd3a2f] | 14 | // |
---|
[51b7345] | 15 | |
---|
[ea6332d] | 16 | #include <ostream> // for ostream, basic_ostream, operator<<, endl |
---|
| 17 | |
---|
| 18 | #include "Type.h" // for TypeInstType, Type, StructInstType, UnionInstType |
---|
[51b7345] | 19 | #include "TypeSubstitution.h" |
---|
| 20 | |
---|
[0dd3a2f] | 21 | TypeSubstitution::TypeSubstitution() { |
---|
| 22 | } |
---|
[51b7345] | 23 | |
---|
[0dd3a2f] | 24 | TypeSubstitution::TypeSubstitution( const TypeSubstitution &other ) { |
---|
| 25 | initialize( other, *this ); |
---|
[51b7345] | 26 | } |
---|
| 27 | |
---|
[0dd3a2f] | 28 | TypeSubstitution::~TypeSubstitution() { |
---|
| 29 | for ( TypeEnvType::iterator i = typeEnv.begin(); i != typeEnv.end(); ++i ) { |
---|
| 30 | delete( i->second ); |
---|
| 31 | } |
---|
| 32 | for ( VarEnvType::iterator i = varEnv.begin(); i != varEnv.end(); ++i ) { |
---|
| 33 | delete( i->second ); |
---|
| 34 | } |
---|
[51b7345] | 35 | } |
---|
| 36 | |
---|
[0dd3a2f] | 37 | TypeSubstitution &TypeSubstitution::operator=( const TypeSubstitution &other ) { |
---|
| 38 | if ( this == &other ) return *this; |
---|
| 39 | initialize( other, *this ); |
---|
| 40 | return *this; |
---|
[51b7345] | 41 | } |
---|
| 42 | |
---|
[0dd3a2f] | 43 | void TypeSubstitution::initialize( const TypeSubstitution &src, TypeSubstitution &dest ) { |
---|
| 44 | dest.typeEnv.clear(); |
---|
| 45 | dest.varEnv.clear(); |
---|
| 46 | dest.add( src ); |
---|
[51b7345] | 47 | } |
---|
| 48 | |
---|
[0dd3a2f] | 49 | void TypeSubstitution::add( const TypeSubstitution &other ) { |
---|
| 50 | for ( TypeEnvType::const_iterator i = other.typeEnv.begin(); i != other.typeEnv.end(); ++i ) { |
---|
| 51 | typeEnv[ i->first ] = i->second->clone(); |
---|
| 52 | } // for |
---|
| 53 | for ( VarEnvType::const_iterator i = other.varEnv.begin(); i != other.varEnv.end(); ++i ) { |
---|
| 54 | varEnv[ i->first ] = i->second->clone(); |
---|
| 55 | } // for |
---|
[51b7345] | 56 | } |
---|
| 57 | |
---|
[0dd3a2f] | 58 | void TypeSubstitution::add( std::string formalType, Type *actualType ) { |
---|
| 59 | TypeEnvType::iterator i = typeEnv.find( formalType ); |
---|
| 60 | if ( i != typeEnv.end() ) { |
---|
| 61 | delete i->second; |
---|
| 62 | } // if |
---|
| 63 | typeEnv[ formalType ] = actualType->clone(); |
---|
[51b7345] | 64 | } |
---|
| 65 | |
---|
[0dd3a2f] | 66 | void TypeSubstitution::remove( std::string formalType ) { |
---|
| 67 | TypeEnvType::iterator i = typeEnv.find( formalType ); |
---|
| 68 | if ( i != typeEnv.end() ) { |
---|
| 69 | delete i->second; |
---|
| 70 | typeEnv.erase( formalType ); |
---|
| 71 | } // if |
---|
[51b7345] | 72 | } |
---|
| 73 | |
---|
[0dd3a2f] | 74 | Type *TypeSubstitution::lookup( std::string formalType ) const { |
---|
| 75 | TypeEnvType::const_iterator i = typeEnv.find( formalType ); |
---|
[8c49c0e] | 76 | |
---|
[084184b] | 77 | // break on not in substitution set |
---|
| 78 | if ( i == typeEnv.end() ) return 0; |
---|
[8c49c0e] | 79 | |
---|
[084184b] | 80 | // attempt to transitively follow TypeInstType links. |
---|
| 81 | while ( TypeInstType *actualType = dynamic_cast< TypeInstType* >( i->second ) ) { |
---|
| 82 | const std::string& typeName = actualType->get_name(); |
---|
[8c49c0e] | 83 | |
---|
[084184b] | 84 | // break cycles in the transitive follow |
---|
| 85 | if ( formalType == typeName ) break; |
---|
[8c49c0e] | 86 | |
---|
[084184b] | 87 | // Look for the type this maps to, returning previous mapping if none-such |
---|
| 88 | i = typeEnv.find( typeName ); |
---|
| 89 | if ( i == typeEnv.end() ) return actualType; |
---|
| 90 | } |
---|
[8c49c0e] | 91 | |
---|
[084184b] | 92 | // return type from substitution set |
---|
| 93 | return i->second; |
---|
[8c49c0e] | 94 | |
---|
[084184b] | 95 | #if 0 |
---|
[0dd3a2f] | 96 | if ( i == typeEnv.end() ) { |
---|
| 97 | return 0; |
---|
| 98 | } else { |
---|
| 99 | return i->second; |
---|
| 100 | } // if |
---|
[084184b] | 101 | #endif |
---|
[51b7345] | 102 | } |
---|
| 103 | |
---|
[0dd3a2f] | 104 | bool TypeSubstitution::empty() const { |
---|
| 105 | return typeEnv.empty() && varEnv.empty(); |
---|
[51b7345] | 106 | } |
---|
| 107 | |
---|
[2ec65ad] | 108 | namespace { |
---|
| 109 | struct EnvTrimmer { |
---|
| 110 | TypeSubstitution * env, * newEnv; |
---|
| 111 | EnvTrimmer( TypeSubstitution * env, TypeSubstitution * newEnv ) : env( env ), newEnv( newEnv ){} |
---|
| 112 | void previsit( TypeDecl * tyDecl ) { |
---|
| 113 | // transfer known bindings for seen type variables |
---|
| 114 | if ( Type * t = env->lookup( tyDecl->name ) ) { |
---|
| 115 | newEnv->add( tyDecl->name, t ); |
---|
| 116 | } |
---|
| 117 | } |
---|
| 118 | }; |
---|
| 119 | } // namespace |
---|
| 120 | |
---|
| 121 | /// reduce environment to just the parts that are referenced in a given expression |
---|
| 122 | TypeSubstitution * TypeSubstitution::newFromExpr( Expression * expr, TypeSubstitution * env ) { |
---|
| 123 | if ( env ) { |
---|
| 124 | TypeSubstitution * newEnv = new TypeSubstitution(); |
---|
| 125 | PassVisitor<EnvTrimmer> trimmer( env, newEnv ); |
---|
| 126 | expr->accept( trimmer ); |
---|
| 127 | return newEnv; |
---|
| 128 | } |
---|
| 129 | return nullptr; |
---|
| 130 | } |
---|
| 131 | |
---|
[0dd3a2f] | 132 | void TypeSubstitution::normalize() { |
---|
[e9a715d3] | 133 | PassVisitor<Substituter> sub( *this, true ); |
---|
[0dd3a2f] | 134 | do { |
---|
[e9a715d3] | 135 | sub.pass.subCount = 0; |
---|
| 136 | sub.pass.freeOnly = true; |
---|
[0dd3a2f] | 137 | for ( TypeEnvType::iterator i = typeEnv.begin(); i != typeEnv.end(); ++i ) { |
---|
[e9a715d3] | 138 | i->second = i->second->acceptMutator( sub ); |
---|
[0dd3a2f] | 139 | } |
---|
[e9a715d3] | 140 | } while ( sub.pass.subCount ); |
---|
[51b7345] | 141 | } |
---|
| 142 | |
---|
[e9a715d3] | 143 | Type * TypeSubstitution::Substituter::postmutate( TypeInstType *inst ) { |
---|
| 144 | BoundVarsType::const_iterator bound = boundVars.find( inst->name ); |
---|
[0dd3a2f] | 145 | if ( bound != boundVars.end() ) return inst; |
---|
[5382492] | 146 | |
---|
[e9a715d3] | 147 | TypeEnvType::const_iterator i = sub.typeEnv.find( inst->get_name() ); |
---|
| 148 | if ( i == sub.typeEnv.end() ) { |
---|
[0dd3a2f] | 149 | return inst; |
---|
| 150 | } else { |
---|
[d0d5054] | 151 | // cut off infinite loop for the case where a type is bound to itself. |
---|
| 152 | // Note: this does not prevent cycles in the general case, so it may be necessary to do something more sophisticated here. |
---|
| 153 | // TODO: investigate preventing type variables from being bound to themselves in the first place. |
---|
| 154 | if ( TypeInstType * replacement = dynamic_cast< TypeInstType * >( i->second ) ) { |
---|
| 155 | if ( inst->name == replacement->name ) { |
---|
| 156 | return inst; |
---|
| 157 | } |
---|
| 158 | } |
---|
| 159 | // std::cerr << "found " << inst->name << ", replacing with " << i->second << std::endl; |
---|
[0dd3a2f] | 160 | subCount++; |
---|
[e9a715d3] | 161 | Type * newtype = i->second->clone(); |
---|
[6f95000] | 162 | newtype->get_qualifiers() |= inst->get_qualifiers(); |
---|
[0dd3a2f] | 163 | delete inst; |
---|
[d0d5054] | 164 | // Note: need to recursively apply substitution to the new type because normalize does not substitute bound vars, but bound vars must be substituted when not in freeOnly mode. |
---|
| 165 | return newtype->acceptMutator( *visitor ); |
---|
[0dd3a2f] | 166 | } // if |
---|
| 167 | } |
---|
| 168 | |
---|
[e9a715d3] | 169 | Expression * TypeSubstitution::Substituter::postmutate( NameExpr * nameExpr ) { |
---|
| 170 | VarEnvType::const_iterator i = sub.varEnv.find( nameExpr->name ); |
---|
| 171 | if ( i == sub.varEnv.end() ) { |
---|
[0dd3a2f] | 172 | return nameExpr; |
---|
| 173 | } else { |
---|
| 174 | subCount++; |
---|
| 175 | delete nameExpr; |
---|
| 176 | return i->second->clone(); |
---|
| 177 | } // if |
---|
[51b7345] | 178 | } |
---|
| 179 | |
---|
[e9a715d3] | 180 | void TypeSubstitution::Substituter::premutate( Type * type ) { |
---|
| 181 | GuardValue( boundVars ); |
---|
[37a3b8f9] | 182 | // bind type variables from forall-qualifiers |
---|
[0dd3a2f] | 183 | if ( freeOnly ) { |
---|
[e9a715d3] | 184 | for ( Type::ForallList::const_iterator tyvar = type->forall.begin(); tyvar != type->forall.end(); ++tyvar ) { |
---|
| 185 | boundVars.insert( (*tyvar)->name ); |
---|
[0dd3a2f] | 186 | } // for |
---|
| 187 | } // if |
---|
[51b7345] | 188 | } |
---|
| 189 | |
---|
[37a3b8f9] | 190 | template< typename TypeClass > |
---|
[e9a715d3] | 191 | void TypeSubstitution::Substituter::handleAggregateType( TypeClass * type ) { |
---|
| 192 | GuardValue( boundVars ); |
---|
[37a3b8f9] | 193 | // bind type variables from forall-qualifiers |
---|
| 194 | if ( freeOnly ) { |
---|
[e9a715d3] | 195 | for ( Type::ForallList::const_iterator tyvar = type->forall.begin(); tyvar != type->forall.end(); ++tyvar ) { |
---|
| 196 | boundVars.insert( (*tyvar)->name ); |
---|
[37a3b8f9] | 197 | } // for |
---|
[c7a3081] | 198 | // bind type variables from generic type instantiations |
---|
| 199 | std::list< TypeDecl* > *baseParameters = type->get_baseParameters(); |
---|
[e9a715d3] | 200 | if ( baseParameters && ! type->parameters.empty() ) { |
---|
[c7a3081] | 201 | for ( std::list< TypeDecl* >::const_iterator tyvar = baseParameters->begin(); tyvar != baseParameters->end(); ++tyvar ) { |
---|
[e9a715d3] | 202 | boundVars.insert( (*tyvar)->name ); |
---|
[c7a3081] | 203 | } // for |
---|
| 204 | } // if |
---|
[ed94eac] | 205 | } // if |
---|
[44b7088] | 206 | } |
---|
| 207 | |
---|
[e9a715d3] | 208 | void TypeSubstitution::Substituter::premutate( StructInstType * aggregateUseType ) { |
---|
| 209 | handleAggregateType( aggregateUseType ); |
---|
[89e6ffc] | 210 | } |
---|
| 211 | |
---|
[e9a715d3] | 212 | void TypeSubstitution::Substituter::premutate( UnionInstType *aggregateUseType ) { |
---|
| 213 | handleAggregateType( aggregateUseType ); |
---|
[89e6ffc] | 214 | } |
---|
| 215 | |
---|
[50377a4] | 216 | void TypeSubstitution::print( std::ostream &os, Indenter indent ) const { |
---|
| 217 | os << indent << "Types:" << std::endl; |
---|
[0dd3a2f] | 218 | for ( TypeEnvType::const_iterator i = typeEnv.begin(); i != typeEnv.end(); ++i ) { |
---|
[50377a4] | 219 | os << indent+1 << i->first << " -> "; |
---|
| 220 | i->second->print( os, indent+2 ); |
---|
[0dd3a2f] | 221 | os << std::endl; |
---|
| 222 | } // for |
---|
[50377a4] | 223 | os << indent << "Non-types:" << std::endl; |
---|
[0dd3a2f] | 224 | for ( VarEnvType::const_iterator i = varEnv.begin(); i != varEnv.end(); ++i ) { |
---|
[50377a4] | 225 | os << indent+1 << i->first << " -> "; |
---|
| 226 | i->second->print( os, indent+2 ); |
---|
[0dd3a2f] | 227 | os << std::endl; |
---|
| 228 | } // for |
---|
[51b7345] | 229 | } |
---|
| 230 | |
---|
[5382492] | 231 | std::ostream & operator<<( std::ostream & out, const TypeSubstitution & sub ) { |
---|
| 232 | sub.print( out ); |
---|
| 233 | return out; |
---|
| 234 | } |
---|
| 235 | |
---|
| 236 | |
---|
[0dd3a2f] | 237 | // Local Variables: // |
---|
| 238 | // tab-width: 4 // |
---|
| 239 | // mode: c++ // |
---|
| 240 | // compile-command: "make install" // |
---|
| 241 | // End: // |
---|