Show map -> transition array -> descriptor array to the heap profiler.

Show map -> transition array -> descriptor array to the heap profiler.


BUG=chromium:142625
Committed: https://code.google.com/p/v8/source/detail?r=12321

[Toon Verwaest, 2012-08-16 10:41:59]

PTAL.

[yurys, 2012-08-16 12:42:53]

Please provide a test for this in test/cctest/test-heap-profiler.cc

https://chromiumcodereview.appspot.com/10830309/diff/6001/src/profile-generat...
File src/profile-generator.cc (right):

https://chromiumcodereview.appspot.com/10830309/diff/6001/src/profile-generat...
src/profile-generator.cc:2015: SetInternalReference(transitions, entry,
This way we will add direct link map->descriptors to the heap snapshot. Why not
extract all this block into ExtractTransitionArrayReferences and call it from
V8HeapExplorer::ExtractReferences? Or you can not discriminate between
TransitionArray and simple FixedArray? That way we would get fair
map->transitions->descriptors chain.

[Toon Verwaest, 2012-08-16 13:43:53]

Added a simple test case checking the maps descriptors and transitions.

https://chromiumcodereview.appspot.com/10830309/diff/6001/src/profile-generat...
File src/profile-generator.cc (right):

https://chromiumcodereview.appspot.com/10830309/diff/6001/src/profile-generat...
src/profile-generator.cc:2015: SetInternalReference(transitions, entry,
This is an internal detail that we do not want to expose to the user. We just
want to show that a map has descriptors and transitions.

Transition arrays can indeed not be distinguished from other fixed arrays.

On 2012/08/16 12:42:53, Yury Semikhatsky wrote:
> This way we will add direct link map->descriptors to the heap snapshot. Why
not
> extract all this block into ExtractTransitionArrayReferences and call it from
> V8HeapExplorer::ExtractReferences? Or you can not discriminate between
> TransitionArray and simple FixedArray? That way we would get fair
> map->transitions->descriptors chain.

[yurys, 2012-08-16 14:08:51]

lgtm