1/* SPDX-License-Identifier: GPL-2.0 */
 2#include <linux/linkage.h>
 3
 4/*
 5 * Multiply operation for 32 bit integers.
 6 *	Input :	Operand1 in Reg r5
 7 *		Operand2 in Reg r6
 8 *	Output: Result [op1 * op2] in Reg r3
 9 */
10	.text
11	.globl	__mulsi3
12	.type __mulsi3,  @function
13	.ent __mulsi3
14
15__mulsi3:
16	.frame	r1, 0, r15
17	add	r3, r0, r0
18	beqi	r5, result_is_zero /* multiply by zero */
19	beqi	r6, result_is_zero /* multiply by zero */
20	bgeid	r5, r5_pos
21	xor	r4, r5, r6 /* get the sign of the result */
22	rsubi	r5, r5, 0 /* make r5 positive */
23r5_pos:
24	bgei	r6, r6_pos
25	rsubi	r6, r6, 0 /* make r6 positive */
26r6_pos:
27	bri	l1
28l2:
29	add	r5, r5, r5
30l1:
31	srl	r6, r6
32	addc	r7, r0, r0
33	beqi	r7, l2
34	bneid	r6, l2
35	add	r3, r3, r5
36	blti	r4, negateresult
37	rtsd	r15, 8
38	nop
39negateresult:
40	rtsd	r15, 8
41	rsub	r3, r3, r0
42result_is_zero:
43	rtsd	r15, 8
44	addi	r3, r0, 0
45
46.size __mulsi3,  . - __mulsi3
47.end __mulsi3

 
 1#include <linux/linkage.h>
 2
 3/*
 4 * Multiply operation for 32 bit integers.
 5 *	Input :	Operand1 in Reg r5
 6 *		Operand2 in Reg r6
 7 *	Output: Result [op1 * op2] in Reg r3
 8 */
 9	.text
10	.globl	__mulsi3
11	.type __mulsi3,  @function
12	.ent __mulsi3
13
14__mulsi3:
15	.frame	r1, 0, r15
16	add	r3, r0, r0
17	beqi	r5, result_is_zero /* multiply by zero */
18	beqi	r6, result_is_zero /* multiply by zero */
19	bgeid	r5, r5_pos
20	xor	r4, r5, r6 /* get the sign of the result */
21	rsubi	r5, r5, 0 /* make r5 positive */
22r5_pos:
23	bgei	r6, r6_pos
24	rsubi	r6, r6, 0 /* make r6 positive */
25r6_pos:
26	bri	l1
27l2:
28	add	r5, r5, r5
29l1:
30	srl	r6, r6
31	addc	r7, r0, r0
32	beqi	r7, l2
33	bneid	r6, l2
34	add	r3, r3, r5
35	blti	r4, negateresult
36	rtsd	r15, 8
37	nop
38negateresult:
39	rtsd	r15, 8
40	rsub	r3, r3, r0
41result_is_zero:
42	rtsd	r15, 8
43	addi	r3, r0, 0
44
45.size __mulsi3,  . - __mulsi3
46.end __mulsi3