X87: new classes: implement default constructors

src/x87/full-codegen-x87.cc

Index: src/x87/full-codegen-x87.cc
diff --git a/src/x87/full-codegen-x87.cc b/src/x87/full-codegen-x87.cc
index 5965ea4af2188e356fe07af72f06394796a2919a..b45f20dcd7b6153b18e41716dc37045bb219a9fd 100644
--- a/src/x87/full-codegen-x87.cc
+++ b/src/x87/full-codegen-x87.cc
@@ -2943,8 +2943,7 @@ void FullCodeGenerator::EmitResolvePossiblyDirectEval(int arg_count) {
 }
 
 
-void FullCodeGenerator::EmitLoadSuperConstructor(SuperReference* super_ref) {
-  DCHECK(super_ref != NULL);
+void FullCodeGenerator::EmitLoadSuperConstructor() {
   __ push(Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
   __ CallRuntime(Runtime::kGetPrototype, 1);
 }
@@ -3062,7 +3061,7 @@ void FullCodeGenerator::VisitCall(Call* expr) {
       EmitSuperConstructorCall(expr);
     } else {
       SuperReference* super_ref = callee->AsSuperReference();
-      EmitLoadSuperConstructor(super_ref);
+      EmitLoadSuperConstructor();
       __ push(result_register());
       VisitForStackValue(super_ref->this_var());
       EmitCall(expr, CallICState::METHOD);
@@ -3135,7 +3134,7 @@ void FullCodeGenerator::EmitSuperConstructorCall(Call* expr) {
   __ push(eax);
 
   SuperReference* super_ref = expr->expression()->AsSuperReference();
-  EmitLoadSuperConstructor(super_ref);
+  EmitLoadSuperConstructor();
   __ push(result_register());
 
   Variable* this_var = super_ref->this_var()->var();
@@ -4057,6 +4056,55 @@ void FullCodeGenerator::EmitCallFunction(CallRuntime* expr) {
 }
 
 
+void FullCodeGenerator::EmitDefaultConstructorCallSuper(CallRuntime* expr) {
+  Variable* new_target_var = scope()->DeclarationScope()->new_target_var();
+  GetVar(eax, new_target_var);
+  __ push(eax);
+
+  EmitLoadSuperConstructor();
+  __ push(result_register());
+
+  // Check if the calling frame is an arguments adaptor frame.
+  Label adaptor_frame, args_set_up, runtime;
+  __ mov(edx, Operand(ebp, StandardFrameConstants::kCallerFPOffset));
+  __ mov(ecx, Operand(edx, StandardFrameConstants::kContextOffset));
+  __ cmp(ecx, Immediate(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ j(equal, &adaptor_frame);
+  // default constructor has no arguments, so no adaptor frame means no args.
+  __ mov(eax, Immediate(0));
+  __ jmp(&args_set_up);
+
+  // Copy arguments from adaptor frame.
+  {
+    __ bind(&adaptor_frame);
+    __ mov(ecx, Operand(edx, ArgumentsAdaptorFrameConstants::kLengthOffset));
+    __ SmiUntag(ecx);
+
+    // Subtract 1 from arguments count, for new.target.
+    __ sub(ecx, Immediate(1));
+    __ mov(eax, ecx);
+    __ lea(edx, Operand(edx, ecx, times_pointer_size,
+                        StandardFrameConstants::kCallerSPOffset));
+    Label loop;
+    __ bind(&loop);
+    __ push(Operand(edx, -1 * kPointerSize));
+    __ sub(edx, Immediate(kPointerSize));
+    __ dec(ecx);
+    __ j(not_zero, &loop);
+  }
+
+  __ bind(&args_set_up);
+  __ mov(edi, Operand(esp, eax, times_pointer_size, 0));
+
+  CallConstructStub stub(isolate(), SUPER_CONSTRUCTOR_CALL);
+  __ call(stub.GetCode(), RelocInfo::CONSTRUCT_CALL);
+
+  __ Drop(1);
+
+  context()->Plug(eax);
+}
+
+
 void FullCodeGenerator::EmitRegExpConstructResult(CallRuntime* expr) {
   // Load the arguments on the stack and call the stub.
   RegExpConstructResultStub stub(isolate());