still emit global load instructions when 'undefined' is used as lhs

When using undefined/NaN as LHS instructions, we need to emit
them as global loads to get the correct runtime type error.

Amends c8a2e4acb101967c254d7e9d3c4e7d9f25c5eecc

Change-Id: Ic03fb88e43b4f1c7e5dfb99faa78e7d35a3a6f8a
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

1 files changed, 14 insertions, 8 deletions

diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index b4004765ff..f6ac4e7957 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -1389,14 +1389,6 @@ Codegen::Reference Codegen::referenceForName(const QString &name, bool isLhs)
     }
 
     if (!c->parent && !c->forceLookupByName() && _context->compilationMode != EvalCode && c->compilationMode != QmlBinding) {
-        // these value properties of the global object are immutable, we we can directly convert them
-        // to their numeric value here
-        if (name == QStringLiteral("undefined"))
-            return Reference::fromConst(this, Encode::undefined());
-        else if (name == QStringLiteral("Infinity"))
-            return Reference::fromConst(this, Encode(qInf()));
-        else if (name == QStringLiteral("Nan"))
-            return Reference::fromConst(this, Encode(qQNaN()));
         Reference r = Reference::fromName(this, name);
         r.global = true;
         return r;
@@ -3075,6 +3067,20 @@ void Codegen::Reference::loadInAccumulator() const
         return;
     }
     case Name:
+        if (global) {
+            // these value properties of the global object are immutable, we we can directly convert them
+            // to their numeric value here
+            if (name == QStringLiteral("undefined")) {
+                Reference::fromConst(codegen, Encode::undefined()).loadInAccumulator();
+                return;
+            } else if (name == QStringLiteral("Infinity")) {
+                Reference::fromConst(codegen, Encode(qInf())).loadInAccumulator();
+                return;
+            } else if (name == QStringLiteral("Nan")) {
+                Reference::fromConst(codegen, Encode(qQNaN())).loadInAccumulator();
+                return;
+            }
+        }
         if (codegen->useFastLookups && global) {
             Instruction::LoadGlobalLookup load;
             load.index = codegen->registerGlobalGetterLookup(nameAsIndex());