blob: 4b0b04ab1c7d12deb2016306722dddd3e83316b0 [file] [log] [blame]
/* Unsigned 32 bit division optimized for Epiphany.
Copyright (C) 2009-2021 Free Software Foundation, Inc.
Contributed by Embecosm on behalf of Adapteva, Inc.
This file is part of GCC.
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 3, or (at your option) any
later version.
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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#include "epiphany-asm.h"
/* Because we handle a divident with bit 31 set with truncating integer
arithmetic, there is no rounding-related overflow. */
FSTAB (__umodsi3,T_UINT)
.global SYM(__umodsi3)
.balign 4
HIDDEN_FUNC(__umodsi3)
SYM(__umodsi3):
float r2,r0
mov TMP1,%low(0xb0800000) ; ??? this would be faster with small data
float TMP2,r1
movt TMP1,%high(0xb0800000)
asr TMP0,r0,8
sub TMP0,TMP0,TMP1
mov TMP1,%low(.L0step)
movgteu r2,TMP0
sub r2,r2,TMP2
blteu .L0step
asr r2,r2,23
movt TMP1,%high(.L0step)
lsl TMP2,r2,3
lsl r2,r1,r2` sub r2,r0,r2` movgteu r0,r2 ; STEP(r2)
sub r2,TMP1,TMP2
jr r2
#define STEP(n) lsl.l r2,r1,n` sub r2,r0,r2` movgteu r0,r2
.balign 8,,2
STEP(31)` STEP(30)` STEP(29)` STEP(28)`
STEP(27)` STEP(26)` STEP(25)` STEP(24)`
STEP(23)` STEP(22)` STEP(21)` STEP(20)`
STEP(19)` STEP(18)` STEP(17)` STEP(16)`
STEP(15)` STEP(14)` STEP(13)` STEP(12)`
STEP(11)` STEP(10)` STEP(9)` STEP(8)`
STEP(7)` STEP(6)` STEP(5)` STEP(4)` STEP(3)` STEP(2)` STEP(1)
.L0step:STEP(0)
.Lret_r0:
rts
ENDFUNC(__umodsi3)