Add dynamic stack frame alignment to optimized functions with untagged doubles on the stack.

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 3395531cf5ca91301df5ffe6d188ff853d7587e7..6c221d0a0f88fa047e66cb8c0cf7e29875b2ec5b 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -2242,6 +2242,13 @@ bool Heap::CreateInitialObjects() {
   }
   set_arguments_marker(obj);
 
+  { MaybeObject* maybe_obj = CreateOddball("frame_alignment_marker",
+                                           Smi::FromInt(-5),

[Kevin Millikin (Chromium), 2011/09/23 09:38:49]

I guess it's useful to give the hidden oddballs distinct toNumber values, but
then you should either reorder their allocation so the numbers are consecutive
or renumber them.

[William Hesse, 2011/09/23 12:50:11]

Done.

+                                           Oddball::kFrameAlignmentMarker);
+    if (!maybe_obj->ToObject(&obj)) return false;
+  }
+  set_frame_alignment_marker(obj);
+
   { MaybeObject* maybe_obj = CreateOddball("no_interceptor_result_sentinel",
                                            Smi::FromInt(-2),
                                            Oddball::kOther);