Correctly setup exit frame when calling into allocation tracker

src/x64/code-stubs-x64.cc

Index: src/x64/code-stubs-x64.cc
diff --git a/src/x64/code-stubs-x64.cc b/src/x64/code-stubs-x64.cc
index b3ab8c1e7588306dda1dacc8d8f6f6f032700c7f..3371e5515414833fa8a53a14b9fbc1f85f255595 100644
--- a/src/x64/code-stubs-x64.cc
+++ b/src/x64/code-stubs-x64.cc
@@ -5817,6 +5817,31 @@ void InternalArrayConstructorStub::Generate(MacroAssembler* masm) {
 }
 
 
+void RecordObjectAllocationStub::Generate(MacroAssembler* masm) {
+  // ----------- S t a t e -------------
+  //  -- rsp[0]  : return address
+  //  -- rsp[8]  : new object address
+  //  -- rsp[16] : object size
+  // -----------------------------------
+  Isolate* isolate = masm->isolate();
+  FrameScope scope(masm, StackFrame::MANUAL);
+  __ EnterApiExitFrame(0);
+
+  __ PushSafepointRegisters();
+  __ PrepareCallCFunction(3);
+  __ movq(arg_reg_3, Operand(rbp,
+      kFPOnStackSize + kPCOnStackSize + 1 * kPointerSize));
+  __ movq(arg_reg_2, Operand(rbp, kFPOnStackSize + kPCOnStackSize));
+  __ movq(arg_reg_1, isolate, RelocInfo::EXTERNAL_REFERENCE);

[Yang, 2013/10/30 15:12:57]

If you need to erect a frame and also pass the isolate, why don't you simply
call into a runtime function using CallRuntime? That uses the CEntryStub and
takes care of the isolate.

[yurys, 2013/10/31 08:56:01]

There are two reasons for this:
1. CallRuntime doesn't preserve registers. Since we call HeapProfiler in the
middle of allocation we should be careful not to change current state of the
instrumented code.
2. Does a lot of checks related to GC which are unnecessary in our case since
the allocation hook is guaranteed not to do any heap allocations. As long as
we'd like to minimize perf impact of the allocation tracker we'd rather avoid
unnecessary checks.

+  __ CallCFunction(
+      ExternalReference::record_object_allocation_function(isolate), 3);
+  __ PopSafepointRegisters();
+
+  __ LeaveApiExitFrame(false);
+  __ ret(0);
+}
+
+
 #undef __
 
 } }  // namespace v8::internal