Changeset bb666f64 for src/ResolvExpr/AlternativeFinder.cc

Timestamp:

Oct 25, 2017, 4:25:20 PM (6 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:

13a6154

Parents:

68195a6

Message:

Fix polymorphic-to-monomorphic function specialization for casts and initializers [fixes #27]

File:

• src/ResolvExpr/AlternativeFinder.cc (modified) (3 diffs)

src/ResolvExpr/AlternativeFinder.cc

@@ -319 +319 @@
         Cost computeExpressionConversionCost( Expression *& actualExpr, Type * formalType, const SymTab::Indexer &indexer, const TypeEnvironment & env ) {
                 Cost convCost = computeConversionCost( actualExpr->result, formalType, indexer, env );
-                // if ( convCost != Cost::zero ) {
-
-                // xxx - temporary -- ignore poly cost, since this causes some polymorphic functions to be cast, which causes the specialize
-                // pass to try to specialize them, which currently does not work. Once that is fixed, remove the next 3 lines and uncomment the
-                // previous line.
+
+                // if there is a non-zero conversion cost, ignoring poly cost, then the expression requires conversion.
+                // ignore poly cost for now, since this requires resolution of the cast to infer parameters and this
+                // does not currently work for the reason stated below.
                 Cost tmpCost = convCost;
                 tmpCost.incPoly( -tmpCost.get_polyCost() );
                 if ( tmpCost != Cost::zero ) {
+                // if ( convCost != Cost::zero ) {
                         Type *newType = formalType->clone();
                         env.apply( newType );
@@ -914 +914 @@
                                 thisCost.incSafe( discardedValues );
                                 Alternative newAlt( restructureCast( i->expr->clone(), toType ), i->env, i->cost, thisCost );
-                                // xxx - this doesn't work at the moment, since inferParameters requires an ApplicationExpr as the alternative.
-                                // Once this works, it should be possible to infer parameters on a cast expression and specialize any function.
-
                                 inferParameters( needAssertions, haveAssertions, newAlt, openVars, back_inserter( candidates ) );
-                                // candidates.emplace_back( std::move( newAlt ) );
                         } // if
                 } // for
@@ -1297 +1293 @@
                                         // count one safe conversion for each value that is thrown away
                                         thisCost.incSafe( discardedValues );
-                                        candidates.push_back( Alternative( new InitExpr( restructureCast( alt.expr->clone(), toType ), initAlt.designation->clone() ), newEnv, alt.cost, thisCost ) );
+                                        Alternative newAlt( new InitExpr( restructureCast( alt.expr->clone(), toType ), initAlt.designation->clone() ), newEnv, alt.cost, thisCost );
+                                        inferParameters( needAssertions, haveAssertions, newAlt, openVars, back_inserter( candidates ) );
                                 }
                         }