shithub: riscv

ref: dc0f1ae1028206a548cc5fad15631d79c212e48a
dir: /sys/src/libc/amd64/strcpy.s/

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	TEXT	strcpy(SB),$0

	MOVL	$0, AX
	MOVQ	$-1, CX
	CLD
/*
 * find end of second string
 */

	MOVQ	p2+8(FP), DI
	REPN;	SCASB

	MOVQ	DI, BX
	SUBQ	p2+8(FP), BX

/*
 * copy the memory
 */
	MOVQ	RARG, DI
	MOVQ	p2+8(FP), SI
/*
 * copy whole longs, if aligned
 */
	MOVQ	DI, CX
	ORQ		SI, CX
	ANDL	$3, CX
	JNE	c3
	MOVQ	BX, CX
	SHRQ	$2, CX
	REP;	MOVSL
/*
 * copy the rest, by bytes
 */
	ANDL	$3, BX
c3:
	MOVL	BX, CX
	REP;	MOVSB

	MOVQ	RARG, AX
	RET