Sema: Use coerceToRValue() to load tuples of lvalues instead of coerc…

…eTupleToTuple()

lib/Sema/CSApply.cpp

@@ -5259,13 +5259,7 @@ Expr *ExprRewriter::coerceExistential(Expr *expr, Type toType,
   // Load tuples with lvalue elements.
   if (auto tupleType = fromType->getAs<TupleType>()) {
     if (tupleType->hasLValueType()) {
-      auto toTuple = tupleType->getRValueType()->castTo<TupleType>();
-      SmallVector<unsigned, 4> sources;
-      bool failed = computeTupleShuffle(tupleType, toTuple, sources);
-      assert(!failed && "Couldn't convert tuple to tuple?");
-      (void)failed;
-
-      coerceTupleToTuple(expr, tupleType, toTuple, locator, sources);
+      expr = cs.coerceToRValue(expr);
     }
   }
 
@@ -6492,6 +6486,10 @@ Expr *ExprRewriter::coerceToType(Expr *expr, Type toType,
     auto toTuple = toType->getAs<TupleType>();
     if (!toTuple)
       break;
+
+    if (fromTuple->hasLValueType() && !toTuple->hasLValueType())
+      return coerceToType(cs.coerceToRValue(expr), toType, locator);
+
     SmallVector<unsigned, 4> sources;
     if (!computeTupleShuffle(fromTuple, toTuple, sources)) {
       return coerceTupleToTuple(expr, fromTuple, toTuple,

lib/Sema/TypeCheckConstraints.cpp

@@ -3134,15 +3134,11 @@ Expr *TypeChecker::coerceToRValue(Expr *expr,
     return FVE;
   }
 
-  // Load lvalues.
-  if (exprTy->is<LValueType>())
-    return addImplicitLoadExpr(expr, getType, setType);
-
   // Walk into parenthesized expressions to update the subexpression.
   if (auto paren = dyn_cast<IdentityExpr>(expr)) {
     auto sub =  coerceToRValue(paren->getSubExpr(), getType, setType);
     paren->setSubExpr(sub);
-    setType(paren, getType(sub));
+    setType(paren, ParenType::get(Context, getType(sub)));
     return paren;
   }
 
@@ -3186,6 +3182,10 @@ Expr *TypeChecker::coerceToRValue(Expr *expr,
     return tuple;
   }
 
+  // Load lvalues.
+  if (exprTy->is<LValueType>())
+    return addImplicitLoadExpr(expr, getType, setType);
+
   // Nothing to do.
   return expr;
 }