FYI Implementing 'super' keyword

src/ia32/full-codegen-ia32.cc

Index: src/ia32/full-codegen-ia32.cc
diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index aacaeeb6a6becee2adfab0f392d048d05fc9cb3f..5bc16e8591016df877958b973bca85b39409b674 100644
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -1278,6 +1278,28 @@ void FullCodeGenerator::VisitVariableProxy(VariableProxy* 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) {
@@ -2220,6 +2242,7 @@ 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(),
@@ -2568,8 +2591,15 @@ void FullCodeGenerator::EmitCallWithLoadIC(Call* expr) {
     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);
@@ -2592,8 +2622,14 @@ void FullCodeGenerator::EmitKeyedCallWithLoadIC(Call* expr,
   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);
 }