git: 9front

ref: bcc5530dab33d4603c421ae31be64d2ff3be7ec5
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