Someone

static inline int clz(unsigned long x)
{
	__asm__ (
	"	.set	push					\n"
	"	.set	mips32					\n"
	"	clz	%0, %1					\n"
	"	.set	pop					\n"
	: "=r" (x)
	: "r" (x));

	return x;
}