root/arch/sh/lib/udiv_qrnnd.S

   1 /* SPDX-License-Identifier: GPL-2.0+ WITH GCC-exception-2.0
   2 
   3    Copyright (C) 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
   4    2004, 2005, 2006
   5    Free Software Foundation, Inc.
   6 */
   7 
   8 !! libgcc routines for the Renesas / SuperH SH CPUs.
   9 !! Contributed by Steve Chamberlain.
  10 !! sac@cygnus.com
  11 
  12 !! ashiftrt_r4_x, ___ashrsi3, ___ashlsi3, ___lshrsi3 routines
  13 !! recoded in assembly by Toshiyasu Morita
  14 !! tm@netcom.com
  15 
  16 /* SH2 optimizations for ___ashrsi3, ___ashlsi3, ___lshrsi3 and
  17    ELF local label prefixes by J"orn Rennecke
  18    amylaar@cygnus.com  */
  19 
  20         /* r0: rn r1: qn */ /* r0: n1 r4: n0 r5: d r6: d1 */ /* r2: __m */
  21         /* n1 < d, but n1 might be larger than d1.  */
  22         .global __udiv_qrnnd_16
  23         .balign 8
  24 __udiv_qrnnd_16:
  25         div0u
  26         cmp/hi r6,r0
  27         bt .Lots
  28         .rept 16
  29         div1 r6,r0 
  30         .endr
  31         extu.w r0,r1
  32         bt 0f
  33         add r6,r0
  34 0:      rotcl r1
  35         mulu.w r1,r5
  36         xtrct r4,r0
  37         swap.w r0,r0
  38         sts macl,r2
  39         cmp/hs r2,r0
  40         sub r2,r0
  41         bt 0f
  42         addc r5,r0
  43         add #-1,r1
  44         bt 0f
  45 1:      add #-1,r1
  46         rts
  47         add r5,r0
  48         .balign 8
  49 .Lots:
  50         sub r5,r0
  51         swap.w r4,r1
  52         xtrct r0,r1
  53         clrt
  54         mov r1,r0
  55         addc r5,r0
  56         mov #-1,r1
  57         bf/s 1b
  58          shlr16 r1
  59 0:      rts
  60          nop