FYI Implementing 'super' keyword

src/ia32/full-codegen-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 1260 matching lines @@
   context()->Plug(eax);
 }
 
 
 void FullCodeGenerator::VisitVariableProxy(VariableProxy* expr) {
   Comment cmnt(masm_, "[ VariableProxy");
   EmitVariableLoad(expr);
 }
 
 
+void FullCodeGenerator::VisitSuperReference(SuperReference* expr) {
+  Comment cnmt(masm_, "[ SuperReference ");
+
+  const Register r = eax;
+  Label super_lookup_failure;
+  __ mov(r, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
+  __ mov(r, FieldOperand(r, JSFunction::kHomeObjectOffset));

[adamk, 2014/08/07 20:38:04]

You mentioned that you're thinking of re-implementing this using private
symbols. Would that turn this load into a runtime call?

+  __ cmp(r, isolate()->factory()->undefined_value());
+  __ j(equal, &super_lookup_failure);
+  __ mov(r, FieldOperand(r, HeapObject::kMapOffset));
+  __ mov(r, FieldOperand(r, Map::kPrototypeOffset));
+  Label done;
+  __ jmp(&done);
+  __ bind(&super_lookup_failure);
+  __ push(Immediate(isolate()->factory()->empty_string()));
+  __ CallRuntime(Runtime::kThrowReferenceError, 1);
+  __ bind(&done);
+  context()->Plug(eax);
+}
+
+
+
 void FullCodeGenerator::EmitLoadGlobalCheckExtensions(VariableProxy* proxy,
                                                       TypeofState typeof_state,
                                                       Label* slow) {
   Register context = esi;
   Register temp = edx;
 
   Scope* s = scope();
   while (s != NULL) {
     if (s->num_heap_slots() > 0) {
       if (s->calls_sloppy_eval()) {
@@ skipping 922 matching lines @@
   // root set.
   __ RecordWriteField(eax, JSGeneratorObject::kResultValuePropertyOffset,
                       ecx, edx, kDontSaveFPRegs);
 }
 
 
 void FullCodeGenerator::EmitNamedPropertyLoad(Property* prop) {
   SetSourcePosition(prop->position());
   Literal* key = prop->key()->AsLiteral();
   DCHECK(!key->value()->IsSmi());
+
   __ mov(LoadIC::NameRegister(), Immediate(key->value()));
   if (FLAG_vector_ics) {
     __ mov(LoadIC::SlotRegister(),
            Immediate(Smi::FromInt(prop->PropertyFeedbackSlot())));
     CallLoadIC(NOT_CONTEXTUAL);
   } else {
     CallLoadIC(NOT_CONTEXTUAL, prop->PropertyFeedbackId());
   }
 }
 
@@ skipping 328 matching lines @@
     // Push undefined as receiver. This is patched in the method prologue if it
     // is a sloppy mode method.
     __ push(Immediate(isolate()->factory()->undefined_value()));
   } else {
     // Load the function from the receiver.
     DCHECK(callee->IsProperty());
     __ mov(LoadIC::ReceiverRegister(), Operand(esp, 0));
     EmitNamedPropertyLoad(callee->AsProperty());
     PrepareForBailoutForId(callee->AsProperty()->LoadId(), TOS_REG);
     // Push the target function under the receiver.
-    __ push(Operand(esp, 0));
-    __ mov(Operand(esp, kPointerSize), eax);
+    if (callee->AsProperty()->IsSuperAccess()) {
+      __ mov(Operand(esp, 0), eax);
+      SuperReference* super_ref =
+          callee->AsProperty()->obj()->AsSuperReference();
+      VisitForStackValue(super_ref->this_var());
+    } else {
+      __ push(Operand(esp, 0));
+      __ mov(Operand(esp, kPointerSize), eax);
+    }
   }
 
   EmitCall(expr, call_type);
 }
 
 
 // Code common for calls using the IC.
 void FullCodeGenerator::EmitKeyedCallWithLoadIC(Call* expr,
                                                 Expression* key) {
   // Load the key.
   VisitForAccumulatorValue(key);
 
   Expression* callee = expr->expression();
 
   // Load the function from the receiver.
   DCHECK(callee->IsProperty());
   __ mov(LoadIC::ReceiverRegister(), Operand(esp, 0));
   __ mov(LoadIC::NameRegister(), eax);
   EmitKeyedPropertyLoad(callee->AsProperty());
   PrepareForBailoutForId(callee->AsProperty()->LoadId(), TOS_REG);
 
   // Push the target function under the receiver.
-  __ push(Operand(esp, 0));
-  __ mov(Operand(esp, kPointerSize), eax);
+  if (callee->AsProperty()->IsSuperAccess()) {
+    __ mov(Operand(esp, 0), eax);
+    SuperReference* super_ref = callee->AsProperty()->obj()->AsSuperReference();
+    VisitForStackValue(super_ref->this_var());
+  } else {
+    __ push(Operand(esp, 0));
+    __ mov(Operand(esp, kPointerSize), eax);
+  }
 
   EmitCall(expr, CallIC::METHOD);
 }
 
 
 void FullCodeGenerator::EmitCall(Call* expr, CallIC::CallType call_type) {
   // Load the arguments.
   ZoneList<Expression*>* args = expr->arguments();
   int arg_count = args->length();
   { PreservePositionScope scope(masm()->positions_recorder());
@@ skipping 2218 matching lines @@
   DCHECK_EQ(isolate->builtins()->OsrAfterStackCheck()->entry(),
             Assembler::target_address_at(call_target_address,
                                          unoptimized_code));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32