https://bugs.webkit.org/show_bug.cgi?id=52946        

Rubber-stamped by Maciej Stachowiak.

SunSpider reports no change.

* runtime/MachineStackMarker.cpp:
(JSC::swapIfBackwards): Added a helper function for handling platforms
where the stack can grow in any direction.

(JSC::MachineStackMarker::markCurrentThreadConservativelyInternal):
(JSC::MachineStackMarker::markOtherThreadConservatively): Use the helper
function.

(JSC::isPointerAligned): Use "!" instead of "==0" because a robot told me to.

(JSC::MachineStackMarker::markConservatively): Changed to use a more
standard looping idiom, and to use the helper function above.

* runtime/MarkedSpace.h:
(JSC::MarkedSpace::isCellAligned): Use "!" instead of "==0" because a robot told me to.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@76430 268f45cc-cd09-0410-ab3c-d52691b4dbfc