mulsi3.S
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#include <linux/linkage.h>
/*
* Multiply operation for 32 bit integers.
* Input : Operand1 in Reg r5
* Operand2 in Reg r6
* Output: Result [op1 * op2] in Reg r3
*/
.text
.globl __mulsi3
.type __mulsi3, @function
.ent __mulsi3
__mulsi3:
.frame r1, 0, r15
add r3, r0, r0
beqi r5, result_is_zero /* multiply by zero */
beqi r6, result_is_zero /* multiply by zero */
bgeid r5, r5_pos
xor r4, r5, r6 /* get the sign of the result */
rsubi r5, r5, 0 /* make r5 positive */
r5_pos:
bgei r6, r6_pos
rsubi r6, r6, 0 /* make r6 positive */
r6_pos:
bri l1
l2:
add r5, r5, r5
l1:
srl r6, r6
addc r7, r0, r0
beqi r7, l2
bneid r6, l2
add r3, r3, r5
blti r4, negateresult
rtsd r15, 8
nop
negateresult:
rtsd r15, 8
rsub r3, r3, r0
result_is_zero:
rtsd r15, 8
addi r3, r0, 0
.size __mulsi3, . - __mulsi3
.end __mulsi3