shithub: plan9front

ref: 808acd51f4e78d8883b81a3df6eb1fe1b61bd903
dir: /sys/src/libc/386/cycles.s/

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#define RDTSC 		BYTE $0x0F; BYTE $0x31

TEXT cycles(SB),1,$0		/* time stamp counter; cycles since power up */
	RDTSC
	MOVL	vlong+0(FP), CX	/* &vlong */
	MOVL	AX, 0(CX)	/* lo */
	MOVL	DX, 4(CX)	/* hi */
	RET