Do proper parallel walks of orig+subst types when computing type

properties for struct and enum types.

Author: rjmccall

lib/SIL/IR/TypeLowering.cpp

@@ -749,11 +749,12 @@ namespace {
     RetTy visitTupleType(CanTupleType type, AbstractionPattern origType,
                          IsTypeExpansionSensitive_t isSensitive) {
       RecursiveProperties props;
-      for (unsigned i = 0, e = type->getNumElements(); i < e; ++i) {
-        props.addSubobject(classifyType(origType.getTupleElementType(i),
-                                        type.getElementType(i),
-                                        TC, Expansion));
-      }
+      origType.forEachExpandedTupleElement(type,
+          [&](AbstractionPattern origEltType, CanType substEltType,
+              const TupleTypeElt &elt) {
+        props.addSubobject(
+          classifyType(origEltType, substEltType, TC, Expansion));
+      });
       props = mergeIsTypeExpansionSensitive(isSensitive, props);
       return asImpl().handleAggregateByProperties(type, props);
     }
@@ -2250,12 +2251,12 @@ namespace {
                                  AbstractionPattern origType,
                                  IsTypeExpansionSensitive_t isSensitive) {
       RecursiveProperties properties;
-      for (unsigned i = 0, e = tupleType->getNumElements(); i < e; ++i) {
-        auto eltType = tupleType.getElementType(i);
-        auto origEltType = origType.getTupleElementType(i);
-        auto &lowering = TC.getTypeLowering(origEltType, eltType, Expansion);
-        properties.addSubobject(lowering.getRecursiveProperties());
-      }
+      origType.forEachExpandedTupleElement(tupleType,
+          [&](AbstractionPattern origEltType, CanType substEltType,
+              const TupleTypeElt &elt) {
+        properties.addSubobject(
+          classifyType(origEltType, substEltType, TC, Expansion));
+      });
       properties = mergeIsTypeExpansionSensitive(isSensitive, properties);
 
       return handleAggregateByProperties<LoadableTupleTypeLowering>(tupleType,