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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

.  */

#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)