https://bugs.webkit.org/show_bug.cgi?id=125552

PerformanceTests/SunSpider: 

Reviewed by Oliver Hunt.
        
Use SunSpider as a kind of spot-check for the
no-architecture-specific-optimization paths in the compiler.

* no-architecture-specific-optimizations.yaml: Added.

Source/JavaScriptCore: 

Reviewed by Oliver Hunt.
        
The forward exit was just there so that we wouldn't have to keep the inputs alive up to
the DoubleAsInt32. That's dumb. Forward exits are a complicated piece of machinery and
we shouldn't have it just for a bit of liveness micro-optimization.
        
Also add a bunch of machinery to test this case on X86.

* assembler/AbstractMacroAssembler.h:
(JSC::optimizeForARMv7s):
(JSC::optimizeForARM64):
(JSC::optimizeForX86):
* dfg/DFGFixupPhase.cpp:
(JSC::DFG::FixupPhase::fixupNode):
* dfg/DFGNodeType.h:
* dfg/DFGSpeculativeJIT.cpp:
(JSC::DFG::SpeculativeJIT::compileDoubleAsInt32):
* runtime/Options.h:
* tests/stress/double-as-int32.js: Added.
(foo):
(test):

Tools: 

Reviewed by Oliver Hunt.
        
Add some support for testing the generic (non-X86) paths on X86 by disabling
architecture-specific optimizations (ASO's).

* Scripts/run-javascriptcore-tests:
* Scripts/run-jsc-stress-tests:



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@160411 268f45cc-cd09-0410-ab3c-d52691b4dbfc