linux/arch/sh/lib/udivsi3.S
Takashi YOSHII 3b041227f7 sh: Add plain udivsi3 (not _i4*) for gcc-4.1 and lower.
We chan't share code for udivsi3 and udivsi3_i4, because they
have a different clobber list. Copy udivsi3 from gcc-4.1.2.

As shown in arch/sh/lib/udivsi3.S (and -Os.S),

  .global __udivsi3_i4i
  .global __udivsi3_i4
  .global __udivsi3
__udivsi3_i4i:
  ...

Three symbols are sharing one code, which is actually udivsi3_i4i.
But, this results unwanted code with gcc 4.1.

In gcc, these three are treated as pseudo instructions that have
their own clobber list apart from the usual calling convention.

According to sh's machine description. The clobber list is as
follows:

 - udivsi3_i4i : t,r1,pr,mach,macl
 - udivsi3_i4  : t,r0,r1,r4,r5,pr,dr0,dr2,dr4
 - udivsi3     : t,r4,pr

The caller of udivsi3 will be left with a broken r1 and mac*.

gcc-4.1.x and older(at least to 3.4) generate udivsi3.
ST's gcc-4.1.1 seems to be OK because it has _i4i.

Signed-off-by: Takashi YOSHII <yoshii.takashi@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-12-22 18:43:53 +09:00

87 lines
2.1 KiB
ArmAsm

/* Copyright (C) 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
2004, 2005
Free Software Foundation, Inc.
This file is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.
In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file. (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)
This file is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not, write to
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
!! libgcc routines for the Renesas / SuperH SH CPUs.
!! Contributed by Steve Chamberlain.
!! sac@cygnus.com
.balign 4
.global __udivsi3
.type __udivsi3, @function
div8:
div1 r5,r4
div7:
div1 r5,r4; div1 r5,r4; div1 r5,r4
div1 r5,r4; div1 r5,r4; div1 r5,r4; rts; div1 r5,r4
divx4:
div1 r5,r4; rotcl r0
div1 r5,r4; rotcl r0
div1 r5,r4; rotcl r0
rts; div1 r5,r4
__udivsi3:
sts.l pr,@-r15
extu.w r5,r0
cmp/eq r5,r0
bf/s large_divisor
div0u
swap.w r4,r0
shlr16 r4
bsr div8
shll16 r5
bsr div7
div1 r5,r4
xtrct r4,r0
xtrct r0,r4
bsr div8
swap.w r4,r4
bsr div7
div1 r5,r4
lds.l @r15+,pr
xtrct r4,r0
swap.w r0,r0
rotcl r0
rts
shlr16 r5
large_divisor:
mov #0,r0
xtrct r4,r0
xtrct r0,r4
bsr divx4
rotcl r0
bsr divx4
rotcl r0
bsr divx4
rotcl r0
bsr divx4
rotcl r0
lds.l @r15+,pr
rts
rotcl r0