These patch will set clang::TargetOptions::ABI and accordingly code will be generated For MIPS target.
I question if ArchSpec::GetClangTargetABI() belongs in ArchSpec. It is very clang specific. Should this just be a function in ClangExpressionParser? Like:
static std::string ClangExpressionParser::GetTargetABI (const ArchSpec &arch);
If no where else will require this target ABI, then this probably should not live in ArchSpec.