Fix issue 825 (LiveEdit vs. function with no locals) in core and for ia32.

src/debug.cc

Index: src/debug.cc
diff --git a/src/debug.cc b/src/debug.cc
index 99256ba21a88a8510978e5578ab0c4f541982b0a..219c2afacfea343890a69f3442de0a5b04907a08 100644
--- a/src/debug.cc
+++ b/src/debug.cc
@@ -2227,6 +2227,13 @@ void Debug::FramesHaveBeenDropped(StackFrame::Id new_break_frame_id,
 }
 
 
+const int Debug::FramePaddingLayout::kInitialSize = 1;
+
+
+// Any even value bigger than (kInitialSize * 2), as needed for stack scanning.
+const int Debug::FramePaddingLayout::kPaddingValue = (kInitialSize + 1) * 2;

[Yang, 2012/05/02 11:38:34]

Use Smi::FromInt to get tagged smi values since x64 tags differently. Why does
the value need to be larger than kInitialSize (smi-tagged)?

[Peter Rybin, 2012/05/02 23:46:33]

Done
This is how liveedit part works. It reads from the frame base and first that it
sees are padding words. It iterates until they end and this is counter.
Therefore padding words mustn't look like any possible value of counter word.

+
+
 bool Debug::IsDebugGlobal(GlobalObject* global) {
   return IsLoaded() && global == debug_context()->global();
 }