root/arch/microblaze/lib/mulsi3.S

   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 */
  23 r5_pos:
  24         bgei    r6, r6_pos
  25         rsubi   r6, r6, 0 /* make r6 positive */
  26 r6_pos:
  27         bri     l1
  28 l2:
  29         add     r5, r5, r5
  30 l1:
  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
  39 negateresult:
  40         rtsd    r15, 8
  41         rsub    r3, r3, r0
  42 result_is_zero:
  43         rtsd    r15, 8
  44         addi    r3, r0, 0
  45 
  46 .size __mulsi3,  . - __mulsi3
  47 .end __mulsi3