xref: /OK3568_Linux_fs/kernel/arch/microblaze/lib/mulsi3.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun#include <linux/linkage.h>
3*4882a593Smuzhiyun
4*4882a593Smuzhiyun/*
5*4882a593Smuzhiyun * Multiply operation for 32 bit integers.
6*4882a593Smuzhiyun *	Input :	Operand1 in Reg r5
7*4882a593Smuzhiyun *		Operand2 in Reg r6
8*4882a593Smuzhiyun *	Output: Result [op1 * op2] in Reg r3
9*4882a593Smuzhiyun */
10*4882a593Smuzhiyun	.text
11*4882a593Smuzhiyun	.globl	__mulsi3
12*4882a593Smuzhiyun	.type __mulsi3,  @function
13*4882a593Smuzhiyun	.ent __mulsi3
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun__mulsi3:
16*4882a593Smuzhiyun	.frame	r1, 0, r15
17*4882a593Smuzhiyun	add	r3, r0, r0
18*4882a593Smuzhiyun	beqi	r5, result_is_zero /* multiply by zero */
19*4882a593Smuzhiyun	beqi	r6, result_is_zero /* multiply by zero */
20*4882a593Smuzhiyun	bgeid	r5, r5_pos
21*4882a593Smuzhiyun	xor	r4, r5, r6 /* get the sign of the result */
22*4882a593Smuzhiyun	rsubi	r5, r5, 0 /* make r5 positive */
23*4882a593Smuzhiyunr5_pos:
24*4882a593Smuzhiyun	bgei	r6, r6_pos
25*4882a593Smuzhiyun	rsubi	r6, r6, 0 /* make r6 positive */
26*4882a593Smuzhiyunr6_pos:
27*4882a593Smuzhiyun	bri	l1
28*4882a593Smuzhiyunl2:
29*4882a593Smuzhiyun	add	r5, r5, r5
30*4882a593Smuzhiyunl1:
31*4882a593Smuzhiyun	srl	r6, r6
32*4882a593Smuzhiyun	addc	r7, r0, r0
33*4882a593Smuzhiyun	beqi	r7, l2
34*4882a593Smuzhiyun	bneid	r6, l2
35*4882a593Smuzhiyun	add	r3, r3, r5
36*4882a593Smuzhiyun	blti	r4, negateresult
37*4882a593Smuzhiyun	rtsd	r15, 8
38*4882a593Smuzhiyun	nop
39*4882a593Smuzhiyunnegateresult:
40*4882a593Smuzhiyun	rtsd	r15, 8
41*4882a593Smuzhiyun	rsub	r3, r3, r0
42*4882a593Smuzhiyunresult_is_zero:
43*4882a593Smuzhiyun	rtsd	r15, 8
44*4882a593Smuzhiyun	addi	r3, r0, 0
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun.size __mulsi3,  . - __mulsi3
47*4882a593Smuzhiyun.end __mulsi3
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