Add inspection of whether frame is a construct frame to optimized frames

Add inspection of whether frame is a construct frame to optimized frames

Also avoid that calling Debug::IsBreakAtReturn causes a full doptimization when there are no break points set. The full deoptimization is caused by Debug::IsBreakAtReturn calling Debug::EnsureDebugInfo which will assume that a break point is now set.

R=svenpanne@chromium.org

BUG=v8:1140
TEST=test/mjsunit/debug-evaluate-locals-optimized.js,test/mjsunit/debug-
evaluate-locals-optimized-doubles.js

Committed: http://code.google.com/p/v8/source/detail?r=8573

[Sven Panne, 2011-07-08 08:17:37]

LGTM apart from the small readability issue.

http://codereview.chromium.org/7307035/diff/1/src/runtime.cc
File src/runtime.cc (right):

http://codereview.chromium.org/7307035/diff/1/src/runtime.cc#newcode10069
src/runtime.cc:10069: }
This is a bit hard to read, perhaps:

bool inlined_frame = it.frame()->is_optimized() && deoptimized_frame_index != 0;
bool constructor = !inlined_frame && it.frame()->IsConstructor();

http://www.refactoring.com/catalog/introduceExplainingVariable.html ;-)

Or even better: Can this be moved into IsConstructor? It's a bit hard for me to
judge from its uses.

[Søren Thygesen Gjesse, 2011-07-08 08:43:09]

http://codereview.chromium.org/7307035/diff/1/src/runtime.cc
File src/runtime.cc (right):

http://codereview.chromium.org/7307035/diff/1/src/runtime.cc#newcode10069
src/runtime.cc:10069: }
On 2011/07/08 08:17:37, Sven wrote:
> This is a bit hard to read, perhaps:
> 
> bool inlined_frame = it.frame()->is_optimized() && deoptimized_frame_index !=
0;
> bool constructor = !inlined_frame && it.frame()->IsConstructor();
> 
> http://www.refactoring.com/catalog/introduceExplainingVariable.html ;-)
> 
> Or even better: Can this be moved into IsConstructor? It's a bit hard for me
to
> judge from its uses.

Done. It cannot go into IsConstructor as IsConstructor is a method on the "real"
stack frame for the optimized function containing inlined functions.