New testcase. This now codegens to:

max:
        mov %EAX, DWORD PTR [%ESP + 4]
        mov %ECX, DWORD PTR [%ESP + 8]
        cmp %EAX, %ECX
        cmovle %EAX, %ECX
        ret

Someone should really implement passing arguments through registers for
known-internal functions.  :)

llvm-svn: 12558