Changeset 65cec25

Timestamp:

Jul 13, 2017, 3:06:29 PM (7 years ago)

Author:

Rob Schluntz <rschlunt@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, resolv-new, with_gc

Children:

6b9b047

Parents:

2463d0e

Message:

Compute common type when reference types are involved

File:

• src/ResolvExpr/CommonType.cc (modified) (7 diffs)

src/ResolvExpr/CommonType.cc

@@ -17 +17 @@
 #include "SynTree/Type.h"
 #include "Unify.h"
-
 
 /// #define DEBUG
@@ -31 +30 @@
                 virtual void visit( PointerType *pointerType );
                 virtual void visit( ArrayType *arrayType );
+                virtual void visit( ReferenceType *refType );
                 virtual void visit( FunctionType *functionType );
                 virtual void visit( StructInstType *aggregateUseType );
@@ -42 +42 @@
                 virtual void visit( OneType *oneType );
 
-                void getCommonWithVoidPointer( PointerType* voidPointer, PointerType* otherPointer );
+                template< typename Pointer > void getCommonWithVoidPointer( Pointer* voidPointer, Pointer* otherPointer );
+                template< typename RefType > void handleRefType( RefType *inst, Type *other );
 
                 Type *result;
@@ -52 +53 @@
         };
 
+        Type * handleReference( ReferenceType * refType, Type * other, bool widenFirst, bool widenSecond, const SymTab::Indexer &indexer, TypeEnvironment & env, const OpenVarSet &openVars ) {
+                Type * result = nullptr, * common = nullptr;
+                AssertionSet have, need;
+                OpenVarSet newOpen( openVars );
+                // need unify to bind type variables
+                if ( unify( refType->get_base(), other, env, have, need, newOpen, indexer, common ) ) {
+                        // std::cerr << "unify success" << std::endl;
+                        if ( widenSecond ) {
+                                if ( widenFirst || other->get_qualifiers() <= refType->get_qualifiers() ) {
+                                        result = new ReferenceType( refType->get_qualifiers(), common ); // refType->clone();
+                                        result->get_qualifiers() |= other->get_qualifiers();
+                                }
+                        } else if ( widenFirst ) {
+                                if ( widenSecond || refType->get_qualifiers() <= other->get_qualifiers() ) {
+                                        result = common;
+                                        result->get_qualifiers() |= refType->get_qualifiers();
+                                }
+                        }
+                } else {
+                        // std::cerr << "exact unify failed: " << refType << " " << other << std::endl;
+                }
+                // std::cerr << "common type of reference [" << refType << "] and non-reference [" << other << "] is [" << result << "]" << std::endl;
+                return result;
+        }
+
         Type *commonType( Type *type1, Type *type2, bool widenFirst, bool widenSecond, const SymTab::Indexer &indexer, TypeEnvironment &env, const OpenVarSet &openVars ) {
                 CommonType visitor( type2, widenFirst, widenSecond, indexer, env, openVars );
+
+                ReferenceType * refType1 = dynamic_cast< ReferenceType * >( type1 );
+                ReferenceType * refType2 = dynamic_cast< ReferenceType * >( type2 );
+                if ( (refType1 || refType2) && (! refType1 || ! refType2) ) {
+                        // handle the case where exactly one of the types is a reference type specially
+                        if ( refType1 ) {
+                                return handleReference( refType1, type2, widenFirst, widenSecond, indexer, env, openVars );
+                        } else if ( refType2 ) {
+                                return handleReference( refType2, type1, widenSecond, widenFirst, indexer, env, openVars );
+                        }
+                }
+
                 type1->accept( visitor );
                 Type *result = visitor.get_result();
@@ -142 +180 @@
         }
 
-        void CommonType::getCommonWithVoidPointer( PointerType* voidPointer, PointerType* otherPointer ) {
+        template< typename Pointer >
+        void CommonType::getCommonWithVoidPointer( Pointer* voidPointer, Pointer* otherPointer ) {
                 if ( TypeInstType* var = dynamic_cast< TypeInstType* >( otherPointer->get_base() ) ) {
                         OpenVarSet::const_iterator entry = openVars.find( var->get_name() );
@@ -188 +227 @@
 
         void CommonType::visit( __attribute((unused)) ArrayType *arrayType ) {}
+
+        void CommonType::visit( ReferenceType *refType ) {
+                if ( ReferenceType *otherRef = dynamic_cast< ReferenceType* >( type2 ) ) {
+                        if ( widenFirst && dynamic_cast< VoidType* >( otherRef->get_base() ) && ! isFtype(refType->get_base()) ) {
+                                getCommonWithVoidPointer( otherRef, refType );
+                        } else if ( widenSecond && dynamic_cast< VoidType* >( refType->get_base() ) && ! isFtype(otherRef->get_base()) ) {
+                                getCommonWithVoidPointer( refType, otherRef );
+                        } else if ( ( refType->get_base()->get_qualifiers() >= otherRef->get_base()->get_qualifiers() || widenFirst )
+                                           && ( refType->get_base()->get_qualifiers() <= otherRef->get_base()->get_qualifiers() || widenSecond ) ) {
+                                Type::Qualifiers tq1 = refType->get_base()->get_qualifiers(), tq2 = otherRef->get_base()->get_qualifiers();
+                                refType->get_base()->get_qualifiers() = Type::Qualifiers();
+                                otherRef->get_base()->get_qualifiers() = Type::Qualifiers();
+                                AssertionSet have, need;
+                                OpenVarSet newOpen( openVars );
+                                if ( unifyExact( refType->get_base(), otherRef->get_base(), env, have, need, newOpen, indexer ) ) {
+                                        if ( tq1 < tq2 ) {
+                                                result = refType->clone();
+                                        } else {
+                                                result = otherRef->clone();
+                                        } // if
+                                        result->get_qualifiers() = tq1 | tq2;
+                                } else {
+                                        /// std::cout << "place for ptr-to-type" << std::endl;
+                                } // if
+                                refType->get_base()->get_qualifiers() = tq1;
+                                otherRef->get_base()->get_qualifiers() = tq2;
+                        } // if
+                } else if ( widenSecond && dynamic_cast< ZeroType* >( type2 ) ) {
+                        result = refType->clone();
+                        result->get_qualifiers() |= type2->get_qualifiers();
+                } // if
+        }
+
         void CommonType::visit( __attribute((unused)) FunctionType *functionType ) {}
         void CommonType::visit( __attribute((unused)) StructInstType *aggregateUseType ) {}
@@ -195 +267 @@
                 if ( dynamic_cast< BasicType * >( type2 ) || dynamic_cast< ZeroType* >( type2 ) || dynamic_cast< OneType* >( type2 ) ) {
                         // reuse BasicType, EnumInstType code by swapping type2 with enumInstType
-                        Type * temp = type2;
+                        ValueGuard< Type * > temp( type2 );
                         type2 = enumInstType;
-                        temp->accept( *this );
-                        type2 = temp;
+                        temp.old->accept( *this );
                 } // if
         }