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/* Unsigned 32 bit division optimized for Epiphany.
   Copyright (C) 2009, 2011 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 (__udivsi3,T_UINT)
        .global SYM(__udivsi3)
        .balign 4
        HIDDEN_FUNC(__udivsi3)
SYM(__udivsi3):
        sub TMP0,r0,r1
        bltu .Lret0
        float TMP2,r0
          mov TMP1,%low(0xb0800000) ; ??? this would be faster with small data
        float TMP3,r1
          movt TMP1,%high(0xb0800000)
        asr TMP0,r0,8
        sub TMP0,TMP0,TMP1
        movt TMP1,%high(0x00810000)
        movgteu TMP2,TMP0
        bblt .Lret1
        sub TMP2,TMP2,TMP1
        sub TMP2,TMP2,TMP3
        mov TMP3,0
        movltu TMP2,TMP3
        lsr TMP2,TMP2,23
        lsl r1,r1,TMP2
        mov TMP0,1
        lsl TMP0,TMP0,TMP2
        sub r0,r0,r1
        bltu .Ladd_back
        add TMP3,TMP3,TMP0
        sub r0,r0,r1
        bltu .Ladd_back
.Lsub_loop:; More than two iterations are rare, so it makes sense to leave
           ; this label here to reduce average branch penalties.
        add TMP3,TMP3,TMP0
        sub r0,r0,r1
        bgteu .Lsub_loop
.Ladd_back:
        add r0,r0,r1
        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,TMP3 ; ... and combine with first bits.
        rts
.Lret0: mov r0,0
        rts
.Lret1: mov r0,1
        rts
        ENDFUNC(__udivsi3)