llvm-svn: 81290
void test(long long *P) { *P ^= 1; } into just: _test: movl 4(%esp), %eax xorl $1, (%eax) ret instead of code like this: _test: movl 4(%esp), %ecx xorl $1, (%ecx) movl 4(%ecx), %edx movl %edx, 4(%ecx) ret llvm-svn: 45762