Unify DeleteMember and DeleteSubscript instructions

The delete operator is rarely used, so it's simpler to
unify these into one DeleteProperty instruction.

Change-Id: I8c0d4455b35efb03db2ab0010df70030d774a6ae
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

4 files changed, 15 insertions, 18 deletions

diff --git a/src/qml/compiler/qv4bytecodehandler.cpp b/src/qml/compiler/qv4bytecodehandler.cpp
index 5709d84f58..18fef62dab 100644
--- a/src/qml/compiler/qv4bytecodehandler.cpp
+++ b/src/qml/compiler/qv4bytecodehandler.cpp
@@ -325,11 +325,8 @@ std::vector<int> ByteCodeHandler::collectLabelsInBytecode(const char *code, uint
         COLLECTOR_BEGIN_INSTR(DestructureRestElement)
         COLLECTOR_END_INSTR(DestructureRestElement)
 
-        COLLECTOR_BEGIN_INSTR(DeleteMember)
-        COLLECTOR_END_INSTR(DeleteMember)
-
-        COLLECTOR_BEGIN_INSTR(DeleteSubscript)
-        COLLECTOR_END_INSTR(DeleteSubscript)
+        COLLECTOR_BEGIN_INSTR(DeleteProperty)
+        COLLECTOR_END_INSTR(DeleteProperty)
 
         COLLECTOR_BEGIN_INSTR(DeleteName)
         COLLECTOR_END_INSTR(DeleteName)
diff --git a/src/qml/compiler/qv4codegen.cpp b/src/qml/compiler/qv4codegen.cpp
index e39bb61688..72e6b2bdf5 100644
--- a/src/qml/compiler/qv4codegen.cpp
+++ b/src/qml/compiler/qv4codegen.cpp
@@ -1798,6 +1798,7 @@ bool Codegen::visit(DeleteExpression *ast)
     if (hasError)
         return false;
 
+    RegisterScope scope(this);
     Reference expr = expression(ast->expression);
     if (hasError)
         return false;
@@ -1829,9 +1830,14 @@ bool Codegen::visit(DeleteExpression *ast)
     case Reference::Member: {
         //### maybe add a variant where the base can be in the accumulator?
         expr = expr.asLValue();
-        Instruction::DeleteMember del;
+        Instruction::LoadRuntimeString instr;
+        instr.stringId = expr.propertyNameIndex;
+        bytecodeGenerator->addInstruction(instr);
+        Reference index = Reference::fromStackSlot(this);
+        index.storeConsumeAccumulator();
+        Instruction::DeleteProperty del;
         del.base = expr.propertyBase.stackSlot();
-        del.member = expr.propertyNameIndex;
+        del.index = index.stackSlot();
         bytecodeGenerator->addInstruction(del);
         _expr.setResult(Reference::fromAccumulator(this));
         return false;
@@ -1839,7 +1845,7 @@ bool Codegen::visit(DeleteExpression *ast)
     case Reference::Subscript: {
         //### maybe add a variant where the index can be in the accumulator?
         expr = expr.asLValue();
-        Instruction::DeleteSubscript del;
+        Instruction::DeleteProperty del;
         del.base = expr.elementBase;
         del.index = expr.elementSubscript.stackSlot();
         bytecodeGenerator->addInstruction(del);
diff --git a/src/qml/compiler/qv4instr_moth.cpp b/src/qml/compiler/qv4instr_moth.cpp
index 0fb789f479..b31b3f8584 100644
--- a/src/qml/compiler/qv4instr_moth.cpp
+++ b/src/qml/compiler/qv4instr_moth.cpp
@@ -449,13 +449,9 @@ void dumpBytecode(const char *code, int len, int nLocals, int nFormals, int /*st
         MOTH_BEGIN_INSTR(DestructureRestElement)
         MOTH_END_INSTR(DestructureRestElement)
 
-        MOTH_BEGIN_INSTR(DeleteMember)
-            d << dumpRegister(base, nFormals) << "[" << member << "]";
-        MOTH_END_INSTR(DeleteMember)
-
-        MOTH_BEGIN_INSTR(DeleteSubscript)
+        MOTH_BEGIN_INSTR(DeleteProperty)
             d << dumpRegister(base, nFormals) << "[" << dumpRegister(index, nFormals) << "]";
-        MOTH_END_INSTR(DeleteSubscript)
+        MOTH_END_INSTR(DeleteProperty)
 
         MOTH_BEGIN_INSTR(DeleteName)
             d << name;
diff --git a/src/qml/compiler/qv4instr_moth_p.h b/src/qml/compiler/qv4instr_moth_p.h
index a2bb85749b..4f6767f07f 100644
--- a/src/qml/compiler/qv4instr_moth_p.h
+++ b/src/qml/compiler/qv4instr_moth_p.h
@@ -129,8 +129,7 @@ QT_BEGIN_NAMESPACE
 #define INSTR_IteratorNext(op) INSTRUCTION(op, IteratorNext, 1, value)
 #define INSTR_IteratorClose(op) INSTRUCTION(op, IteratorClose, 1, done)
 #define INSTR_DestructureRestElement(op) INSTRUCTION(op, DestructureRestElement, 0)
-#define INSTR_DeleteMember(op) INSTRUCTION(op, DeleteMember, 2, member, base)
-#define INSTR_DeleteSubscript(op) INSTRUCTION(op, DeleteSubscript, 2, base, index)
+#define INSTR_DeleteProperty(op) INSTRUCTION(op, DeleteProperty, 2, base, index)
 #define INSTR_DeleteName(op) INSTRUCTION(op, DeleteName, 1, name)
 #define INSTR_TypeofName(op) INSTRUCTION(op, TypeofName, 1, name)
 #define INSTR_TypeofValue(op) INSTRUCTION(op, TypeofValue, 0)
@@ -258,8 +257,7 @@ QT_BEGIN_NAMESPACE
     F(IteratorNext) \
     F(IteratorClose) \
     F(DestructureRestElement) \
-    F(DeleteMember) \
-    F(DeleteSubscript) \
+    F(DeleteProperty) \
     F(DeleteName) \
     F(TypeofName) \
     F(TypeofValue) \