https://bugs.webkit.org/show_bug.cgi?id=69299

Reviewed by Geoff Garen.

We don't have sufficient registers to keep both in registers, and DFG JIT will trample esi;
it doesn't matter if the bucketCount gets stomped on (in fact it may add to randomness!),
but it if the timeoutCheck gets trashed we may make calls out to the timout_check stub
function too frequently (regressing performance). This patch has no perf impact on sunspider.

* JavaScriptCore.xcodeproj/project.pbxproj:
* assembler/MacroAssemblerX86.h:
(JSC::MacroAssemblerX86::branchAdd32):
(JSC::MacroAssemblerX86::branchSub32):
    - Added branchSub32 with AbsoluteAddress.
* jit/JIT.cpp:
(JSC::JIT::emitTimeoutCheck):
    - Keep timeout count in memory on X86.
* jit/JITInlineMethods.h:
(JSC::JIT::emitValueProfilingSite):
    - remove X86 specific code, switch bucket count back into a register.
* jit/JITStubs.cpp:
    - Stop initializing esi (it is no longer the timeoutCheck!)
* jit/JSInterfaceJIT.h:
    - change definition of esi to be the bucketCountRegister.
* runtime/JSGlobalData.cpp:
(JSC::JSGlobalData::JSGlobalData):
* runtime/JSGlobalData.h:
    - Add timeoutCount as a property to global data (the counter should be per-thread).



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@96563 268f45cc-cd09-0410-ab3c-d52691b4dbfc