Deoptimizer support for hydrogen stubs that accept a variable number of arguments.

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index ed407e796b637af4072e6be69b85c8cd64fe86c0..1686a5021b7c79822773fb6ffe27278670053abd 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -1312,9 +1312,11 @@ Address StubFailureTrampolineFrame::GetCallerStackPointer() const {
 
 Code* StubFailureTrampolineFrame::unchecked_code() const {
   int i = 0;
-  for (; i <= StubFailureTrampolineStub::kMaxExtraExpressionStackCount; ++i) {
+  for (; i <= 1; ++i) {
     Code* trampoline;
-    StubFailureTrampolineStub(i).FindCodeInCache(&trampoline, isolate());
+    bool acting_as_js_function = (i == 0) ? false : true;

[danno, 2013/03/20 21:07:33]

Since there is only true/false, I think removing the loop is better and just
testing the two versions linearly makes more sense.

[mvstanton, 2013/03/21 11:47:35]

Thanks, I thought this was awkward too, whew.

+    StubFailureTrampolineStub(acting_as_js_function).FindCodeInCache(
+        &trampoline, isolate());
     ASSERT(trampoline != NULL);
     Address current_pc = pc();
     Address code_start = trampoline->instruction_start();