Fix some issues with the delete operator

Properly implement delete operator for identifiers
and local variables.

Change-Id: I8ac55edc80c31a94d11444c9f5c78caf4b131c95
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

llvm_runtime.cpp

@@ -500,14 +500,9 @@ void __qmljs_llvm_delete_member(ExecutionContext *ctx, Value *result, Value *bas
     *result = __qmljs_delete_member(ctx, *base, name);
 }
 
-void __qmljs_llvm_delete_property(ExecutionContext *ctx, Value *result, String *name)
+void __qmljs_llvm_delete_name(ExecutionContext *ctx, Value *result, String *name)
 {
-    *result = __qmljs_delete_property(ctx, name);
-}
-
-void __qmljs_llvm_delete_value(ExecutionContext *ctx, Value *result, Value *value)
-{
-    *result = __qmljs_delete_value(ctx, *value);
+    *result = __qmljs_delete_name(ctx, name);
 }
 
 } // extern "C"

moth/qv4vme_moth.cpp

@@ -262,11 +262,11 @@ VM::Value VME::operator()(QQmlJS::VM::ExecutionContext *context, const uchar *co
     MOTH_END_INSTR(CallBuiltinDeleteSubscript)
 
     MOTH_BEGIN_INSTR(CallBuiltinDeleteName)
-        TEMP(instr.targetTempIndex) = __qmljs_delete_property(context, instr.name);
+        TEMP(instr.targetTempIndex) = __qmljs_delete_name(context, instr.name);
     MOTH_END_INSTR(CallBuiltinDeleteName)
 
     MOTH_BEGIN_INSTR(CallBuiltinDeleteValue)
-        TEMP(instr.targetTempIndex) = __qmljs_delete_value(context, TEMP(instr.tempIndex));
+        TEMP(instr.targetTempIndex) = VM::Value::fromBoolean(false);
     MOTH_END_INSTR(CallBuiltinDeleteValue)
 
     MOTH_BEGIN_INSTR(CreateValue)

qmljs_environment.cpp

@@ -221,6 +221,26 @@ PropertyDescriptor *ExecutionContext::lookupPropertyDescriptor(String *name, Pro
     return 0;
 }
 
+bool ExecutionContext::deleteProperty(String *name)
+{
+    for (DeclarativeEnvironment *ctx = lexicalEnvironment; ctx; ctx = ctx->outer) {
+        if (ctx->withObject) {
+            DeclarativeEnvironment::With *w = ctx->withObject;
+            while (w) {
+                if (w->object->__hasProperty__(this, name))
+                    w->object->__delete__(this, name);
+                w = w->next;
+            }
+        }
+        if (ctx->activation) {
+            if (ctx->activation->__hasProperty__(this, name))
+                ctx->activation->__delete__(this, name);
+        }
+    }
+    // ### throw syntax error in strict mode
+    return true;
+}
+
 void ExecutionContext::inplaceBitOp(Value value, String *name, BinOp op)
 {
     for (DeclarativeEnvironment *ctx = lexicalEnvironment; ctx; ctx = ctx->outer) {

qmljs_environment.h

@@ -118,6 +118,7 @@ struct ExecutionContext
 
     PropertyDescriptor *lookupPropertyDescriptor(String *name, PropertyDescriptor *tmp);
     void inplaceBitOp(Value value, String *name, BinOp op);
+    bool deleteProperty(String *name);
 
     inline uint argumentCount() const { return variableEnvironment->argumentCount; }
     inline Value argument(unsigned int index = 0)

qmljs_objects.h

@@ -411,7 +411,7 @@ struct Object {
     virtual void __put__(ExecutionContext *ctx, String *name, const Value &value, bool throwException = false);
     virtual bool __canPut__(ExecutionContext *ctx, String *name);
     virtual bool __hasProperty__(ExecutionContext *ctx, String *name) const;
-    virtual bool __delete__(ExecutionContext *ctx, String *name, bool throwException);
+    virtual bool __delete__(ExecutionContext *ctx, String *name, bool throwException = false);
     virtual bool __defineOwnProperty__(ExecutionContext *ctx, String *name, PropertyDescriptor *desc, bool throwException = false);
 
     //

qmljs_runtime.cpp

@@ -195,18 +195,9 @@ Value __qmljs_delete_member(ExecutionContext *ctx, Value base, String *name)
     return Value::fromBoolean(obj.objectValue()->__delete__(ctx, name, true));
 }
 
-Value __qmljs_delete_property(ExecutionContext *ctx, String *name)
+Value __qmljs_delete_name(ExecutionContext *ctx, String *name)
 {
-    Object *obj = ctx->lexicalEnvironment->activation;
-    if (!obj)
-        obj = ctx->engine->globalObject.objectValue();
-    return Value::fromBoolean(obj->__delete__(ctx, name, true));
-}
-
-Value __qmljs_delete_value(ExecutionContext *ctx, Value value)
-{
-    Q_UNUSED(value);
-    return __qmljs_throw_type_error(ctx); // ### throw syntax error
+    return Value::fromBoolean(ctx->deleteProperty(name));
 }
 
 Value __qmljs_add_helper(Value left, Value right, ExecutionContext *ctx)

qmljs_runtime.h

@@ -177,8 +177,7 @@ Value __qmljs_not(Value value, ExecutionContext *ctx);
 
 Value __qmljs_delete_subscript(ExecutionContext *ctx, Value base, Value index);
 Value __qmljs_delete_member(ExecutionContext *ctx, Value base, String *name);
-Value __qmljs_delete_property(ExecutionContext *ctx, String *name);
-Value __qmljs_delete_value(ExecutionContext *ctx, Value value);
+Value __qmljs_delete_name(ExecutionContext *ctx, String *name);
 
 Value __qmljs_typeof(Value value, ExecutionContext *ctx);
 void __qmljs_throw(Value value, ExecutionContext *context);

qv4isel_masm.cpp

@@ -230,9 +230,15 @@ void InstructionSelection::callActivationProperty(IR::Call *call, IR::Temp *resu
         } else if (IR::Subscript *ss = call->args->expr->asSubscript()) {
             generateFunctionCall(result, __qmljs_delete_subscript, ContextRegister, ss->base->asTemp(), ss->index->asTemp());
             return;
-        } else {
-            assert(!"builtin_delete: unimplemented");
-            Q_UNIMPLEMENTED();
+        } else if (IR::Name *n = call->args->expr->asName()) {
+            generateFunctionCall(result, __qmljs_delete_name, ContextRegister, n);
+            return;
+        } else if (call->args->expr->asTemp()){
+            // ### should throw in strict mode
+            Address dest = loadTempAddress(ScratchRegister, result);
+            Value v = Value::fromBoolean(false);
+            storeValue(v, dest);
+            return;
         }
         break;
     }