arch/sh/lib/udiv_qrnnd.S

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