linux/arch/sparc/lib/udivdi3.S
David S. Miller 1b35a57b1c sparc32: Kill off software 32-bit multiply/divide routines.
For the explicit calls to .udiv/.umul in assembler, I made a
mechanical (read as: safe) transformation.  I didn't attempt
to make any simplifications.

In particular, __ndelay and __udelay can be simplified significantly.
Some of the %y reads are unnecessary and these routines have no need
any longer for allocating a register window, they can be leaf
functions.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-15 11:23:47 -07:00

260 lines
5.3 KiB
ArmAsm

/* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
This file is part of GNU CC.
GNU CC 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.
GNU CC 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 GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
.text
.align 4
.globl __udivdi3
__udivdi3:
save %sp,-104,%sp
mov %i3,%o3
cmp %i2,0
bne .LL40
mov %i1,%i3
cmp %o3,%i0
bleu .LL41
mov %i3,%o1
! Inlined udiv_qrnnd
mov 32,%g1
subcc %i0,%o3,%g0
1: bcs 5f
addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
sub %i0,%o3,%i0 ! this kills msb of n
addx %i0,%i0,%i0 ! so this cannot give carry
subcc %g1,1,%g1
2: bne 1b
subcc %i0,%o3,%g0
bcs 3f
addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
b 3f
sub %i0,%o3,%i0 ! this kills msb of n
4: sub %i0,%o3,%i0
5: addxcc %i0,%i0,%i0
bcc 2b
subcc %g1,1,%g1
! Got carry from n. Subtract next step to cancel this carry.
bne 4b
addcc %o1,%o1,%o1 ! shift n1n0 and a 0-bit in lsb
sub %i0,%o3,%i0
3: xnor %o1,0,%o1
! End of inline udiv_qrnnd
b .LL45
mov 0,%o2
.LL41:
cmp %o3,0
bne .LL77
mov %i0,%o2
mov 1,%o0
mov 0,%o1
wr %g0, 0, %y
udiv %o0, %o1, %o0
mov %o0,%o3
mov %i0,%o2
.LL77:
mov 0,%o4
! Inlined udiv_qrnnd
mov 32,%g1
subcc %o4,%o3,%g0
1: bcs 5f
addxcc %o2,%o2,%o2 ! shift n1n0 and a q-bit in lsb
sub %o4,%o3,%o4 ! this kills msb of n
addx %o4,%o4,%o4 ! so this cannot give carry
subcc %g1,1,%g1
2: bne 1b
subcc %o4,%o3,%g0
bcs 3f
addxcc %o2,%o2,%o2 ! shift n1n0 and a q-bit in lsb
b 3f
sub %o4,%o3,%o4 ! this kills msb of n
4: sub %o4,%o3,%o4
5: addxcc %o4,%o4,%o4
bcc 2b
subcc %g1,1,%g1
! Got carry from n. Subtract next step to cancel this carry.
bne 4b
addcc %o2,%o2,%o2 ! shift n1n0 and a 0-bit in lsb
sub %o4,%o3,%o4
3: xnor %o2,0,%o2
! End of inline udiv_qrnnd
mov %o4,%i0
mov %i3,%o1
! Inlined udiv_qrnnd
mov 32,%g1
subcc %i0,%o3,%g0
1: bcs 5f
addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
sub %i0,%o3,%i0 ! this kills msb of n
addx %i0,%i0,%i0 ! so this cannot give carry
subcc %g1,1,%g1
2: bne 1b
subcc %i0,%o3,%g0
bcs 3f
addxcc %o1,%o1,%o1 ! shift n1n0 and a q-bit in lsb
b 3f
sub %i0,%o3,%i0 ! this kills msb of n
4: sub %i0,%o3,%i0
5: addxcc %i0,%i0,%i0
bcc 2b
subcc %g1,1,%g1
! Got carry from n. Subtract next step to cancel this carry.
bne 4b
addcc %o1,%o1,%o1 ! shift n1n0 and a 0-bit in lsb
sub %i0,%o3,%i0
3: xnor %o1,0,%o1
! End of inline udiv_qrnnd
b .LL78
mov %o1,%l1
.LL40:
cmp %i2,%i0
bleu .LL46
sethi %hi(65535),%o0
b .LL73
mov 0,%o1
.LL46:
or %o0,%lo(65535),%o0
cmp %i2,%o0
bgu .LL53
mov %i2,%o1
cmp %i2,256
addx %g0,-1,%o0
b .LL59
and %o0,8,%o2
.LL53:
sethi %hi(16777215),%o0
or %o0,%lo(16777215),%o0
cmp %o1,%o0
bgu .LL59
mov 24,%o2
mov 16,%o2
.LL59:
srl %o1,%o2,%o1
sethi %hi(__clz_tab),%o0
or %o0,%lo(__clz_tab),%o0
ldub [%o1+%o0],%o0
add %o0,%o2,%o0
mov 32,%o1
subcc %o1,%o0,%o2
bne,a .LL67
mov 32,%o0
cmp %i0,%i2
bgu .LL69
cmp %i3,%o3
blu .LL73
mov 0,%o1
.LL69:
b .LL73
mov 1,%o1
.LL67:
sub %o0,%o2,%o0
sll %i2,%o2,%i2
srl %o3,%o0,%o1
or %i2,%o1,%i2
sll %o3,%o2,%o3
srl %i0,%o0,%o1
sll %i0,%o2,%i0
srl %i3,%o0,%o0
or %i0,%o0,%i0
sll %i3,%o2,%i3
mov %i0,%o5
mov %o1,%o4
! Inlined udiv_qrnnd
mov 32,%g1
subcc %o4,%i2,%g0
1: bcs 5f
addxcc %o5,%o5,%o5 ! shift n1n0 and a q-bit in lsb
sub %o4,%i2,%o4 ! this kills msb of n
addx %o4,%o4,%o4 ! so this cannot give carry
subcc %g1,1,%g1
2: bne 1b
subcc %o4,%i2,%g0
bcs 3f
addxcc %o5,%o5,%o5 ! shift n1n0 and a q-bit in lsb
b 3f
sub %o4,%i2,%o4 ! this kills msb of n
4: sub %o4,%i2,%o4
5: addxcc %o4,%o4,%o4
bcc 2b
subcc %g1,1,%g1
! Got carry from n. Subtract next step to cancel this carry.
bne 4b
addcc %o5,%o5,%o5 ! shift n1n0 and a 0-bit in lsb
sub %o4,%i2,%o4
3: xnor %o5,0,%o5
! End of inline udiv_qrnnd
mov %o4,%i0
mov %o5,%o1
! Inlined umul_ppmm
wr %g0,%o1,%y ! SPARC has 0-3 delay insn after a wr
sra %o3,31,%g2 ! Do not move this insn
and %o1,%g2,%g2 ! Do not move this insn
andcc %g0,0,%g1 ! Do not move this insn
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,%o3,%g1
mulscc %g1,0,%g1
add %g1,%g2,%o0
rd %y,%o2
cmp %o0,%i0
bgu,a .LL73
add %o1,-1,%o1
bne,a .LL45
mov 0,%o2
cmp %o2,%i3
bleu .LL45
mov 0,%o2
add %o1,-1,%o1
.LL73:
mov 0,%o2
.LL45:
mov %o1,%l1
.LL78:
mov %o2,%l0
mov %l0,%i0
mov %l1,%i1
ret
restore