root/arch/arm/lib/muldi3.S

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *  linux/arch/arm/lib/muldi3.S
   4  *
   5  *  Author:     Nicolas Pitre
   6  *  Created:    Oct 19, 2005
   7  *  Copyright:  Monta Vista Software, Inc.
   8  */
   9 
  10 #include <linux/linkage.h>
  11 #include <asm/assembler.h>
  12 
  13 #ifdef __ARMEB__
  14 #define xh r0
  15 #define xl r1
  16 #define yh r2
  17 #define yl r3
  18 #else
  19 #define xl r0
  20 #define xh r1
  21 #define yl r2
  22 #define yh r3
  23 #endif
  24 
  25 ENTRY(__muldi3)
  26 ENTRY(__aeabi_lmul)
  27 
  28         mul     xh, yl, xh
  29         mla     xh, xl, yh, xh
  30         mov     ip, xl, lsr #16
  31         mov     yh, yl, lsr #16
  32         bic     xl, xl, ip, lsl #16
  33         bic     yl, yl, yh, lsl #16
  34         mla     xh, yh, ip, xh
  35         mul     yh, xl, yh
  36         mul     xl, yl, xl
  37         mul     ip, yl, ip
  38         adds    xl, xl, yh, lsl #16
  39         adc     xh, xh, yh, lsr #16
  40         adds    xl, xl, ip, lsl #16
  41         adc     xh, xh, ip, lsr #16
  42         ret     lr
  43 
  44 ENDPROC(__muldi3)
  45 ENDPROC(__aeabi_lmul)