Reviewed by Gavin Barraclough.

        Fix unaligned data access in YARR_JIT on ARMv5 and below.
        https://bugs.webkit.org/show_bug.cgi?id=29695

        On ARMv5 and below all data access should be naturally aligned.
        In the YARR_JIT there is a case when character pairs are
        loaded from the input string, but this data access is not
        naturally aligned. This fix introduces load32WithUnalignedHalfWords
        and branch32WithUnalignedHalfWords functions which contain
        naturally aligned memory loads - half word loads - on ARMv5 and below.

        * assembler/MacroAssemblerARM.cpp:
        (JSC::MacroAssemblerARM::load32WithUnalignedHalfWords):
        * assembler/MacroAssemblerARM.h:
        (JSC::MacroAssemblerARM::load32WithUnalignedHalfWords):
        (JSC::MacroAssemblerARM::branch32WithUnalignedHalfWords):
        * assembler/MacroAssemblerARMv7.h:
        (JSC::MacroAssemblerARMv7::load32WithUnalignedHalfWords):
        (JSC::MacroAssemblerARMv7::branch32):
        (JSC::MacroAssemblerARMv7::branch32WithUnalignedHalfWords):
        * assembler/MacroAssemblerX86Common.h:
        (JSC::MacroAssemblerX86Common::load32WithUnalignedHalfWords):
        (JSC::MacroAssemblerX86Common::branch32WithUnalignedHalfWords):
        * wtf/Platform.h:
        * yarr/RegexJIT.cpp:
        (JSC::Yarr::RegexGenerator::generatePatternCharacterPair):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@48782 268f45cc-cd09-0410-ab3c-d52691b4dbfc