git: 9front

ref: 2d4a2c5c2065a32b6b5bd6a0e887af1574a8dfec
dir: /sys/src/ape/lib/ap/386/cycles.s/

View raw version 
#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