Remove code handling parameters rewritten to properties (aka synthetic properties).

src/x64/full-codegen-x64.cc

Index: src/x64/full-codegen-x64.cc
===================================================================
--- src/x64/full-codegen-x64.cc	(revision 9022)
+++ src/x64/full-codegen-x64.cc	(working copy)
@@ -45,7 +45,6 @@
 
 
 static unsigned GetPropertyId(Property* property) {
-  if (property->is_synthetic()) return AstNode::kNoNumber;
   return property->id();
 }
 
@@ -665,97 +664,69 @@
   Comment cmnt(masm_, "[ Declaration");
   ASSERT(variable != NULL);  // Must have been resolved.
   Slot* slot = variable->AsSlot();
-  Property* prop = variable->AsProperty();
+  ASSERT(slot != NULL);
+  switch (slot->type()) {
+    case Slot::PARAMETER:
+    case Slot::LOCAL:
+      if (mode == Variable::CONST) {
+        __ LoadRoot(kScratchRegister, Heap::kTheHoleValueRootIndex);
+        __ movq(Operand(rbp, SlotOffset(slot)), kScratchRegister);
+      } else if (function != NULL) {
+        VisitForAccumulatorValue(function);
+        __ movq(Operand(rbp, SlotOffset(slot)), result_register());
+      }
+      break;
 
-  if (slot != NULL) {
-    switch (slot->type()) {
-      case Slot::PARAMETER:
-      case Slot::LOCAL:
-        if (mode == Variable::CONST) {
-          __ LoadRoot(kScratchRegister, Heap::kTheHoleValueRootIndex);
-          __ movq(Operand(rbp, SlotOffset(slot)), kScratchRegister);
-        } else if (function != NULL) {
-          VisitForAccumulatorValue(function);
-          __ movq(Operand(rbp, SlotOffset(slot)), result_register());
-        }
-        break;
+    case Slot::CONTEXT:
+      // We bypass the general EmitSlotSearch because we know more about
+      // this specific context.
 
-      case Slot::CONTEXT:
-        // We bypass the general EmitSlotSearch because we know more about
-        // this specific context.
-
-        // The variable in the decl always resides in the current function
-        // context.
-        ASSERT_EQ(0, scope()->ContextChainLength(variable->scope()));
-        if (FLAG_debug_code) {
-          // Check that we're not inside a with or catch context.
-          __ movq(rbx, FieldOperand(rsi, HeapObject::kMapOffset));
-          __ CompareRoot(rbx, Heap::kWithContextMapRootIndex);
-          __ Check(not_equal, "Declaration in with context.");
-          __ CompareRoot(rbx, Heap::kCatchContextMapRootIndex);
-          __ Check(not_equal, "Declaration in catch context.");
-        }
-        if (mode == Variable::CONST) {
-          __ LoadRoot(kScratchRegister, Heap::kTheHoleValueRootIndex);
-          __ movq(ContextOperand(rsi, slot->index()), kScratchRegister);
-          // No write barrier since the hole value is in old space.
-        } else if (function != NULL) {
-          VisitForAccumulatorValue(function);
-          __ movq(ContextOperand(rsi, slot->index()), result_register());
-          int offset = Context::SlotOffset(slot->index());
-          __ movq(rbx, rsi);
-          __ RecordWrite(rbx, offset, result_register(), rcx);
-        }
-        break;
-
-      case Slot::LOOKUP: {
-        __ push(rsi);
-        __ Push(variable->name());
-        // Declaration nodes are always introduced in one of two modes.
-        ASSERT(mode == Variable::VAR ||
-               mode == Variable::CONST ||
-               mode == Variable::LET);
-        PropertyAttributes attr = (mode == Variable::CONST) ? READ_ONLY : NONE;
-        __ Push(Smi::FromInt(attr));
-        // Push initial value, if any.
-        // Note: For variables we must not push an initial value (such as
-        // 'undefined') because we may have a (legal) redeclaration and we
-        // must not destroy the current value.
-        if (mode == Variable::CONST) {
-          __ PushRoot(Heap::kTheHoleValueRootIndex);
-        } else if (function != NULL) {
-          VisitForStackValue(function);
-        } else {
-          __ Push(Smi::FromInt(0));  // no initial value!
-        }
-        __ CallRuntime(Runtime::kDeclareContextSlot, 4);
-        break;
+      // The variable in the decl always resides in the current function
+      // context.
+      ASSERT_EQ(0, scope()->ContextChainLength(variable->scope()));
+      if (FLAG_debug_code) {
+        // Check that we're not inside a with or catch context.
+        __ movq(rbx, FieldOperand(rsi, HeapObject::kMapOffset));
+        __ CompareRoot(rbx, Heap::kWithContextMapRootIndex);
+        __ Check(not_equal, "Declaration in with context.");
+        __ CompareRoot(rbx, Heap::kCatchContextMapRootIndex);
+        __ Check(not_equal, "Declaration in catch context.");
       }
-    }
-
-  } else if (prop != NULL) {
-    // A const declaration aliasing a parameter is an illegal redeclaration.
-    ASSERT(mode != Variable::CONST);
-    if (function != NULL) {
-      // We are declaring a function that rewrites to a property.
-      // Use (keyed) IC to set the initial value.  We cannot visit the
-      // rewrite because it's shared and we risk recording duplicate AST
-      // IDs for bailouts from optimized code.
-      ASSERT(prop->obj()->AsVariableProxy() != NULL);
-      { AccumulatorValueContext for_object(this);
-        EmitVariableLoad(prop->obj()->AsVariableProxy());
+      if (mode == Variable::CONST) {
+        __ LoadRoot(kScratchRegister, Heap::kTheHoleValueRootIndex);
+        __ movq(ContextOperand(rsi, slot->index()), kScratchRegister);
+        // No write barrier since the hole value is in old space.
+      } else if (function != NULL) {
+        VisitForAccumulatorValue(function);
+        __ movq(ContextOperand(rsi, slot->index()), result_register());
+        int offset = Context::SlotOffset(slot->index());
+        __ movq(rbx, rsi);
+        __ RecordWrite(rbx, offset, result_register(), rcx);
       }
-      __ push(rax);
-      VisitForAccumulatorValue(function);
-      __ pop(rdx);
-      ASSERT(prop->key()->AsLiteral() != NULL &&
-             prop->key()->AsLiteral()->handle()->IsSmi());
-      __ Move(rcx, prop->key()->AsLiteral()->handle());
+      break;
 
-      Handle<Code> ic = is_strict_mode()
-          ? isolate()->builtins()->KeyedStoreIC_Initialize_Strict()
-          : isolate()->builtins()->KeyedStoreIC_Initialize();
-      __ call(ic);
+    case Slot::LOOKUP: {
+      __ push(rsi);
+      __ Push(variable->name());
+      // Declaration nodes are always introduced in one of two modes.
+      ASSERT(mode == Variable::VAR ||
+             mode == Variable::CONST ||
+             mode == Variable::LET);
+      PropertyAttributes attr = (mode == Variable::CONST) ? READ_ONLY : NONE;
+      __ Push(Smi::FromInt(attr));
+      // Push initial value, if any.
+      // Note: For variables we must not push an initial value (such as
+      // 'undefined') because we may have a (legal) redeclaration and we
+      // must not destroy the current value.
+      if (mode == Variable::CONST) {
+        __ PushRoot(Heap::kTheHoleValueRootIndex);
+      } else if (function != NULL) {
+        VisitForStackValue(function);
+      } else {
+        __ Push(Smi::FromInt(0));  // no initial value!
+      }
+      __ CallRuntime(Runtime::kDeclareContextSlot, 4);
+      break;
     }
   }
 }
@@ -2169,38 +2140,10 @@
       EmitCallWithIC(expr, key->handle(), RelocInfo::CODE_TARGET);
     } else {
       // Call to a keyed property.
-      // For a synthetic property use keyed load IC followed by function call,
-      // for a regular property use EmitKeyedCallWithIC.
-      if (prop->is_synthetic()) {
-        // Do not visit the object and key subexpressions (they are shared
-        // by all occurrences of the same rewritten parameter).
-        ASSERT(prop->obj()->AsVariableProxy() != NULL);
-        ASSERT(prop->obj()->AsVariableProxy()->var()->AsSlot() != NULL);
-        Slot* slot = prop->obj()->AsVariableProxy()->var()->AsSlot();
-        MemOperand operand = EmitSlotSearch(slot, rdx);
-        __ movq(rdx, operand);
-
-        ASSERT(prop->key()->AsLiteral() != NULL);
-        ASSERT(prop->key()->AsLiteral()->handle()->IsSmi());
-        __ Move(rax, prop->key()->AsLiteral()->handle());
-
-        // Record source code position for IC call.
-        SetSourcePosition(prop->position());
-
-        Handle<Code> ic = isolate()->builtins()->KeyedLoadIC_Initialize();
-        __ call(ic, RelocInfo::CODE_TARGET, GetPropertyId(prop));
-        // Push result (function).
-        __ push(rax);
-        // Push Global receiver.
-        __ movq(rcx, GlobalObjectOperand());
-        __ push(FieldOperand(rcx, GlobalObject::kGlobalReceiverOffset));
-        EmitCallWithStub(expr, NO_CALL_FUNCTION_FLAGS);
-      } else {
-        { PreservePositionScope scope(masm()->positions_recorder());
-          VisitForStackValue(prop->obj());
-        }
-        EmitKeyedCallWithIC(expr, prop->key());
+      { PreservePositionScope scope(masm()->positions_recorder());
+        VisitForStackValue(prop->obj());
       }
+      EmitKeyedCallWithIC(expr, prop->key());
     }
   } else {
     { PreservePositionScope scope(masm()->positions_recorder());
@@ -3599,17 +3542,11 @@
       Variable* var = expr->expression()->AsVariableProxy()->AsVariable();
 
       if (prop != NULL) {
-        if (prop->is_synthetic()) {
-          // Result of deleting parameters is false, even when they rewrite
-          // to accesses on the arguments object.
-          context()->Plug(false);
-        } else {
-          VisitForStackValue(prop->obj());
-          VisitForStackValue(prop->key());
-          __ Push(Smi::FromInt(strict_mode_flag()));
-          __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION);
-          context()->Plug(rax);
-        }
+        VisitForStackValue(prop->obj());
+        VisitForStackValue(prop->key());
+        __ Push(Smi::FromInt(strict_mode_flag()));
+        __ InvokeBuiltin(Builtins::DELETE, CALL_FUNCTION);
+        context()->Plug(rax);
       } else if (var != NULL) {
         // Delete of an unqualified identifier is disallowed in strict mode
         // but "delete this" is.