LLInt SH4 backend implementation
https://bugs.webkit.org/show_bug.cgi?id=112886

Patch by Julien Brianceau <jbrianceau@nds.com> on 2013-04-15
Reviewed by Oliver Hunt.

Source/JavaScriptCore:

* dfg/DFGOperations.cpp:
(JSC):
* jit/JITStubs.cpp:
* llint/LLIntOfflineAsmConfig.h:
* llint/LowLevelInterpreter.asm:
* llint/LowLevelInterpreter32_64.asm:
* offlineasm/arm.rb:
* offlineasm/ast.rb:
* offlineasm/backends.rb:
* offlineasm/instructions.rb:
* offlineasm/mips.rb:
* offlineasm/risc.rb:
* offlineasm/sh4.rb: Added.

Source/WTF:

* wtf/Platform.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@148474 268f45cc-cd09-0410-ab3c-d52691b4dbfc