Global cycle detection analysis.

Global cycle detection analysis.

This adds a detect-cycles flag to the plugin which will cause each compilation unit to output a .graph.json file describing the points-to graph of that compilation unit. The process-graph.py script can then be used to process the graph files to detect cycles involving GC roots.

BUG=334149
R=ager@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=258898

[zerny-chromium, 2014-03-21 09:50:46]

Blink side CL: https://codereview.chromium.org/207393003/

[Mads Ager (chromium), 2014-03-21 11:45:56]

LGTM

https://codereview.chromium.org/207913002/diff/1/tools/clang/blink_gc_plugin/...
File tools/clang/blink_gc_plugin/process-graph.py (right):

https://codereview.chromium.org/207913002/diff/1/tools/clang/blink_gc_plugin/...
tools/clang/blink_gc_plugin/process-graph.py:28: # command line args after
parsing.
Start comments with a capital letter?

https://codereview.chromium.org/207913002/diff/1/tools/clang/blink_gc_plugin/...
tools/clang/blink_gc_plugin/process-graph.py:97: # has type
HashMap<WeakMember<B>, Member<B>> we will have a one
a one -> a

https://codereview.chromium.org/207913002/diff/1/tools/clang/blink_gc_plugin/...
tools/clang/blink_gc_plugin/process-graph.py:126: ['find', dirname, '-name',
'*.graph.json']).split('\n')
We might want to use python APIs for this at some point to avoid making this
script platform specific. Not important now (maybe add a TODO)?

[zerny-chromium, 2014-03-24 07:07:20]

Thanks for the review. Addresses your comments in the new patch-set.

[zerny-chromium, 2014-03-24 07:07:58]

The CQ bit was checked by zerny@chromium.org

[commit-bot: I haz the power, 2014-03-24 07:08:08]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/zerny@chromium.org/207913002/20001

[commit-bot: I haz the power, 2014-03-24 09:38:11]

Change committed as 258898