Changeset 7933351

Timestamp:

Dec 13, 2016, 4:59:46 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:

ea83e00a

Parents:

fc638d2

Message:

add tuple cast resolution code

Location:

src

Files:

• ResolvExpr/AlternativeFinder.cc (modified) (8 diffs)
• ResolvExpr/AlternativeFinder.h (modified) (1 diff)
• SynTree/Type.h (modified) (2 diffs)
• tests/.expect/castError.txt (modified) (1 diff)
• tests/.expect/tupleCast.txt (modified) (1 diff)
• tests/tupleCast.c (modified) (1 diff)

src/ResolvExpr/AlternativeFinder.cc

@@ -185 +185 @@
                         if ( alternatives.begin() == oldBegin ) {
                                 std::ostringstream stream;
-                                stream << "Can't choose between alternatives for expression ";
+                                stream << "Can't choose between " << alternatives.size() << " alternatives for expression ";
                                 expr->print( stream );
                                 stream << "Alternatives are:";
@@ -308 +308 @@
                                         (*actualType)->print( std::cerr, 8 );
                                         std::cerr << std::endl << " to ";
-                                        (*formal)->get_type()->print( std::cerr, 8 );
+                                        (*formalType)->print( std::cerr, 8 );
                                 )
                                 Cost newCost = conversionCost( *actualType, *formalType, indexer, alt.env );
@@ -511 +511 @@
                 if ( ! cur->second ) {
                         inferRecursive( begin, end, newAlt, openVars, decls, newNeed, /*needParents,*/ level, indexer, out );
+                        return; // xxx - should this continue? previously this wasn't here, and it looks like it should be
                 }
                 DeclarationWithType *curDecl = cur->first;
+
                 PRINT(
                         std::cerr << "inferRecursive: assertion is ";
@@ -649 +651 @@
                 AltList candidates;
                 SemanticError errors;
-
                 for ( AltList::const_iterator func = funcFinder.alternatives.begin(); func != funcFinder.alternatives.end(); ++func ) {
                         try {
@@ -758 +759 @@
         void AlternativeFinder::visit( CastExpr *castExpr ) {
                 Type *& toType = castExpr->get_result();
+                assert( toType );
                 toType = resolveTypeof( toType, indexer );
                 SymTab::validateType( toType, &indexer );
@@ -763 +765 @@
 
                 AlternativeFinder finder( indexer, env );
+                finder.targetType = toType;
                 finder.findWithAdjustment( castExpr->get_arg() );
 
@@ -776 +779 @@
                         int discardedValues = (*i).expr->get_result()->size() - castExpr->get_result()->size();
                         if ( discardedValues < 0 ) continue;
-                        // xxx - may need to go into tuple types and extract relavent types and use unifyList
+                        // xxx - may need to go into tuple types and extract relevant types and use unifyList. Note that currently, this does not
+                        // allow casting a tuple to an atomic type (e.g. (int)([1, 2, 3]))
                         // unification run for side-effects
                         unify( castExpr->get_result(), (*i).expr->get_result(), i->env, needAssertions, haveAssertions, openVars, indexer );
@@ -783 +787 @@
                                 // count one safe conversion for each value that is thrown away
                                 thisCost += Cost( 0, 0, discardedValues );
-                                CastExpr *newExpr = castExpr->clone();
-                                newExpr->set_arg( i->expr->clone() );
-                                candidates.push_back( Alternative( newExpr, i->env, i->cost, thisCost ) );
+
+                                Expression * argExpr = i->expr->clone();
+                                if ( argExpr->get_result()->size() > 1 && ! castExpr->get_result()->isVoid() ) {
+                                        // Argument expression is a tuple and the target type is not void. Cast each member of the tuple
+                                        // to its corresponding target type, producing the tuple of those cast expressions. If there are
+                                        // more components of the tuple than components in the target type, then excess components do not
+                                        // come out in the result expression (but UniqueExprs ensure that side effects will still be done).
+                                        if ( Tuples::maybeImpure( argExpr ) && ! dynamic_cast< UniqueExpr * >( argExpr ) ) {
+                                                // expressions which may contain side effects require a single unique instance of the expression.
+                                                argExpr = new UniqueExpr( argExpr );
+                                        }
+                                        std::list< Expression * > componentExprs;
+                                        for ( unsigned int i = 0; i < castExpr->get_result()->size(); i++ ) {
+                                                // cast each component
+                                                TupleIndexExpr * idx = new TupleIndexExpr( argExpr->clone(), i );
+                                                componentExprs.push_back( new CastExpr( idx, castExpr->get_result()->getComponent( i )->clone() ) );
+                                        }
+                                        delete argExpr;
+                                        assert( componentExprs.size() > 0 );
+                                        // produce the tuple of casts
+                                        candidates.push_back( Alternative( new TupleExpr( componentExprs ), i->env, i->cost, thisCost ) );
+                                } else {
+                                        // handle normally
+                                        candidates.push_back( Alternative( new CastExpr( argExpr->clone(), toType->clone() ), i->env, i->cost, thisCost ) );
+                                }
                         } // if
                 } // for

src/ResolvExpr/AlternativeFinder.h

@@ -91 +91 @@
                 AltList alternatives;
                 const TypeEnvironment &env;
+                Type * targetType = nullptr;
         }; // AlternativeFinder
 

src/SynTree/Type.h

@@ -72 +72 @@
         virtual unsigned size() const { return 1; };
         virtual bool isVoid() const { return size() == 0; }
+        virtual Type * getComponent( unsigned i ) { assertf( size() == 1 && i == 0, "Type::getComponent was called with size %d and index %d\n", size(), i ); return this; }
 
         virtual Type *clone() const = 0;
@@ -372 +373 @@
         iterator end() { return types.end(); }
 
+        virtual Type * getComponent( unsigned i ) {
+                assertf( i < size(), "TupleType::getComponent: index %d must be less than size %d", i, size() );
+                return *(begin()+i);
+        }
+
         virtual TupleType *clone() const { return new TupleType( *this ); }
         virtual void accept( Visitor &v ) { v.visit( this ); }

src/tests/.expect/castError.txt

@@ -1 +1 @@
 CFA Version 1.0.0 (debug)
-Error: Can't choose between alternatives for expression Cast of:
+Error: Can't choose between 3 alternatives for expression Cast of:
   Name: f
 

src/tests/.expect/tupleCast.txt

@@ -1 +1 @@
 10 A 3.14
 10 A
+10
 10 65
 ran f

src/tests/tupleCast.c

@@ -20 +20 @@
   printf("%d %c %g\n", ([int, char, float])x);
   printf("%d %c\n", ([int, char])x);
+  printf("%d\n", ([int])x);
+  // printf("%d\n", (int)x);
   printf("%g %g\n", ([double, float])x);
   printf("%d %c\n", ([int, char])f());