Reviewed by Geoff Garen.

https://bugs.webkit.org/show_bug.cgi?id=39252 regressed performance on i386,
by adding an extra indirection to making a native call.  By introducing per-
NativeFunction thunks we can hard code the function pointer into the thunk
so that it need not be loaded from the callee.

* jit/JIT.h:
(JSC::JIT::compileCTINativeCall):
* jit/JITOpcodes.cpp:
(JSC::JIT::privateCompileCTINativeCall):
* jit/JITOpcodes32_64.cpp:
(JSC::JIT::privateCompileCTINativeCall):
* jit/JITPropertyAccess.cpp:
(JSC::JIT::emitSlow_op_get_by_val):
* jit/JITPropertyAccess32_64.cpp:
(JSC::JIT::emitSlow_op_get_by_val):
* jit/JITStubs.cpp:
(JSC::JITThunks::ctiStub):
(JSC::JITThunks::hostFunctionStub):
* jit/JITStubs.h:
* jit/SpecializedThunkJIT.h:
(JSC::SpecializedThunkJIT::finalize):
* jit/ThunkGenerators.cpp:
(JSC::charCodeAtThunkGenerator):
(JSC::charAtThunkGenerator):
(JSC::fromCharCodeThunkGenerator):
(JSC::sqrtThunkGenerator):
(JSC::powThunkGenerator):
* runtime/JSFunction.cpp:
(JSC::JSFunction::JSFunction):
* runtime/JSGlobalData.cpp:
(JSC::JSGlobalData::getHostFunction):
* runtime/JSGlobalData.h:
(JSC::JSGlobalData::getCTIStub):
* runtime/Lookup.cpp:
(JSC::setUpStaticFunctionSlot):
* runtime/StringConstructor.cpp:
(JSC::StringConstructor::StringConstructor):
* wtf/Platform.h:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@59746 268f45cc-cd09-0410-ab3c-d52691b4dbfc