Retro68/gcc/libgcc/config/epiphany/divsi3-float.S
2015-08-28 17:33:40 +02:00

78 lines
2.0 KiB
ArmAsm

/* Signed 32 bit division optimized for Epiphany.
Copyright (C) 2009-2015 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"
FSTAB (__divsi3,T_UINT)
.global SYM(__divsi3)
.balign 4
HIDDEN_FUNC(__divsi3)
SYM(__divsi3):
float TMP2,r0
mov TMP4,0
float TMP1,r1
sub TMP0,TMP4,r0
beq .Lret_r0
movgt r0,TMP0
sub TMP0,TMP4,r1
movgt r1,TMP0
mov TMP0,1
sub TMP2,TMP2,TMP1
asr TMP3,TMP2,31 ; save sign
lsl TMP2,TMP2,1
blt .Lret0
sub TMP1,TMP2,1 ; rounding compensation, avoid overflow
movgte TMP2,TMP1
lsr TMP2,TMP2,24
lsl r1,r1,TMP2
lsl TMP0,TMP0,TMP2
sub TMP1,r0,r1
movgteu r0,TMP1
movgteu TMP4,TMP0
lsl TMP5,TMP0,1
sub TMP1,r0,r1
movgteu r0,TMP1
movgteu TMP4,TMP5
sub TMP1,r1,1
mov r1,%low(.L0step)
movt r1,%high(.L0step)
lsl TMP2,TMP2,3
sub r1,r1,TMP2
jr r1
.rep 30
lsl r0,r0,1
sub.l r1,r0,TMP1
movgteu r0,r1
.endr
.L0step:sub r1,TMP0,1 ; mask result bits from steps ...
and r0,r0,r1
orr r0,r0,TMP4 ; ... and combine with first bit.
eor r0,r0,TMP3 ; restore sign
sub r0,r0,TMP3
.Lret_r0:rts
.Lret0: mov r0,0
rts
ENDFUNC(__divsi3)