[ARMv7] Skip one particularly expensive fastFree() alignment check.
authorakling@apple.com <akling@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Fri, 27 Jun 2014 18:06:41 +0000 (18:06 +0000)
committerakling@apple.com <akling@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Fri, 27 Jun 2014 18:06:41 +0000 (18:06 +0000)
commit0c5d3288cf71d6699b247b523ea81f5b11dc8008
tree454735972d5f818ccb55413016a338ec7d6bb63b
parentb559057e8fcab780661bb4066ebae1b5b16c1116
[ARMv7] Skip one particularly expensive fastFree() alignment check.
<https://webkit.org/b/134402>

The size class alignment check in fastFree() was crazy expensive on ARMv7
due to its use of modulo. Disabling it shaves 470ms off of PLT main thread
time in the web process.

Note that this was very hard to identify in profiles due to TCO.

Reviewed by Gavin Barraclough.

* wtf/FastMalloc.cpp:
(WTF::TCMalloc_ThreadCache::CreateCacheIfNecessary):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@170536 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Source/WTF/ChangeLog
Source/WTF/wtf/FastMalloc.cpp