2010-02-01 01:36:46 +00:00
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/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id$
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*
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* Copyright (C) 2008 by Jens Arnold
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* Copyright (C) 2009 by Andrew Mahone
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*
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* Optimised replacements for libgcc functions
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*
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* Based on: libgcc routines for ARM cpu, additional algorithms from ARM System
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* Developer's Guide
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* Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
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* Copyright 1995, 1996, 1998, 1999, 2000, 2003, 2004, 2005
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* Free Software Foundation, Inc.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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#include <config.h>
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.macro ARM_SDIV32_PRE numerator, divisor, sign
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/* sign[31] = divisor sign */
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ands \sign, \divisor, #1<<31
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rsbeq \divisor, \divisor, #0
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/* sign[31] = result sign, sign[0:30], C = numerator sign */
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eors \sign, \sign, \numerator, asr #32
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rsbcs \numerator, \numerator, #0
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.endm
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.macro ARM_SDIV32_POST quotient, remainder, sign
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movs \sign, \sign, lsl #1
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.ifnc "", "\quotient"
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rsbcs \quotient, \quotient, #0
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.endif
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.ifnc "", "\remainder"
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rsbmi \remainder, \remainder, #0
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.endif
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.endm
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#if ARM_ARCH < 5
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.macro ARMV4_UDIV32_BODY numerator, divisor, quotient, remainder, tmp, bits, div0label, return
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.ifnc "", "\div0label"
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rsbs \divisor, \divisor, #0
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beq \div0label
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.else
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rsb \divisor, \divisor, #0
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.endif
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/* This SWAR divider requires a numerator less than 1<<31, because it must
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be able to shift the remainder left at each step without shifting out
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topmost bit. Since a shift might be needed for the aligned remainder to
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exceed the divisor, the topmost bit must be unset at the start to avoid
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this overflow case. The original numerator is saved so that the result
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can be corrected after the reduced division completes. */
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cmn \numerator, \divisor
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.ifc "", "\quotient"
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.ifc "\numerator", "\remainder"
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.if \return
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bxcc lr
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.else
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b 99f
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.endif
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.else
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bcc 20f
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.endif
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.else
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bcc 20f
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.endif
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movs \tmp, \numerator
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movmi \numerator, \numerator, lsr #1
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mov \bits, #30
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.set shift, 16
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.rept 5
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cmn \divisor, \numerator, lsr #shift
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subcs \bits, \bits, #shift
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movcs \divisor, \divisor, lsl #shift
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.set shift, shift >> 1
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.endr
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adds \numerator, \numerator, \divisor
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subcc \numerator, \numerator, \divisor
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add pc, pc, \bits, lsl #3
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nop
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.rept 30
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adcs \numerator, \divisor, \numerator, lsl #1
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subcc \numerator, \numerator, \divisor
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.endr
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adc \numerator, \numerator, \numerator
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movs \tmp, \tmp, asr #1
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rsb \bits, \bits, #31
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bmi 10f
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.ifc "", "\quotient"
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mov \remainder, \numerator, lsr \bits
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.else
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.ifc "", "\remainder"
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mov \divisor, \numerator, lsr \bits
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eor \quotient, \numerator, \divisor, lsl \bits
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.else
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mov \remainder, \numerator, lsr \bits
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eor \quotient, \numerator, \remainder, lsl \bits
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.endif
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.endif
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2010-02-01 02:35:28 +00:00
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.ifne \return
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2010-02-01 01:36:46 +00:00
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bx lr
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.else
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b 99f
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.endif
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10:
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mov \tmp, \numerator, lsr \bits
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eor \numerator, \numerator, \tmp, lsl \bits
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sub \bits, \bits, #1
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adc \tmp, \tmp, \tmp
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adds \tmp, \tmp, \divisor, asr \bits
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.ifnc "", "\quotient"
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adc \quotient, \numerator, \numerator
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.endif
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.ifnc "", "\remainder"
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subcc \remainder, \tmp, \divisor, asr \bits
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movcs \remainder, \tmp
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.endif
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2010-02-01 02:35:28 +00:00
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.ifne \return
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2010-02-01 01:36:46 +00:00
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bx lr
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.else
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b 99f
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.endif
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20:
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.ifnc "", "\remainder"
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.ifnc "\remainder", "\numerator"
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mov \remainder, \numerator
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.endif
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.endif
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.ifnc "", "\quotient"
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mov \quotient, #0
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.endif
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2010-02-01 02:35:28 +00:00
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.ifne \return
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2010-02-01 01:36:46 +00:00
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bx lr
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.else
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99:
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.endif
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.endm
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.macro ARMV4_SDIV32_BODY numerator, divisor, quotient, remainder, bits, sign, div0label, return
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/* When this is wrapped for signed division, the wrapper code will handle
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inverting the divisor, and also the zero divisor test. */
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ARM_SDIV32_PRE \numerator, \divisor, \sign
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.ifnc "", "\div0label"
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tst \divisor, \divisor
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beq \div0label
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.endif
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/* This SWAR divider requires a numerator less than 1<<31, because it must
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be able to shift the remainder left at each step without shifting out
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topmost bit. With signed inputs, whose absolute value may not exceed
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1<<31,this may be accomplished simply by subtracting the divisor before
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beginning division, and adding 1 to the quotient. */
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adds \numerator, \numerator, \divisor
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bcc 20f
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mov \bits, #30
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.set shift, 16
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.rept 5
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cmn \divisor, \numerator, lsr #shift
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subcs \bits, \bits, #shift
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movcs \divisor, \divisor, lsl #shift
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.set shift, shift >> 1
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.endr
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adds \numerator, \numerator, \divisor
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subcc \numerator, \numerator, \divisor
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add pc, pc, \bits, lsl #3
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nop
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.rept 30
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adcs \numerator, \divisor, \numerator, lsl #1
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subcc \numerator, \numerator, \divisor
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.endr
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rsb \bits, \bits, #31
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adc \numerator, \numerator, \numerator
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.ifc "", "\quotient"
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mov \remainder, \numerator, lsr \bits
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.else
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.ifc "", "\remainder"
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mov \divisor, \numerator, lsr \bits
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add \numerator, \numerator, #1
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sub \quotient, \numerator, \divisor, lsl \bits
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.else
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mov \remainder, \numerator, lsr \bits
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add \numerator, \numerator, #1
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sub \quotient, \numerator, \remainder, lsl \bits
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.endif
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.endif
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2010-02-01 02:35:28 +00:00
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.ifne \return
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2010-02-01 01:36:46 +00:00
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ARM_SDIV32_POST \quotient, \remainder, \sign
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bx lr
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.else
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b 99f
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.endif
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20:
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.ifnc "", "\remainder"
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sub \remainder, \numerator, \divisor
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.endif
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.ifnc "", "\quotient"
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mov \quotient, #0
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.endif
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2010-02-01 02:35:28 +00:00
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.ifne \return
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2010-02-01 01:36:46 +00:00
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ARM_SDIV32_POST "", \remainder, \sign
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bx lr
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.else
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99:
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ARM_SDIV32_POST \quotient, \remainder, \sign
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.endif
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.endm
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#else
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.macro ARMV5_UDIV32_BODY numerator, divisor, quotient, remainder, bits, inv, neg, div0label, return
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cmp \numerator, \divisor
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clz \bits, \divisor
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bcc 30f
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mov \inv, \divisor, lsl \bits
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add \neg, pc, \inv, lsr #25
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/* Test whether divisor is 2^N */
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cmp \inv, #1<<31
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/* Load approximate reciprocal */
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ldrhib \inv, [\neg, #.L_udiv_est_table-.-64]
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bls 20f
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subs \bits, \bits, #7
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rsb \neg, \divisor, #0
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/* Scale approximate reciprocal, or else branch to large-divisor path */
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movpl \divisor, \inv, lsl \bits
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bmi 10f
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/* Newton-Raphson iteration to improve reciprocal accuracy */
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mul \inv, \divisor, \neg
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smlawt \divisor, \divisor, \inv, \divisor
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mul \inv, \divisor, \neg
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/* Complete N-R math and produce approximate quotient. Use smmla/smmul on
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ARMv6. */
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#if ARM_ARCH >= 6
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tst \numerator, \numerator
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smmla \divisor, \divisor, \inv, \divisor
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/* Branch to large-numerator handler, or else use smmul if sign bit is not
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2010-02-20 06:29:23 +00:00
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set. This wins on average with random numerators, and should be no
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slower than using umull for small numerator, even if prediction fails.
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*/
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2010-02-01 01:36:46 +00:00
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bmi 40f
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smmul \inv, \numerator, \divisor
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#else
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/* ARMv5e lacks smmul, so always uses umull. */
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mov \bits, #0
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smlal \bits, \divisor, \inv, \divisor
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umull \bits, \inv, \numerator, \divisor
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#endif
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/* Calculate remainder and correct result. */
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add \numerator, \numerator, \neg
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.ifnc "", "\remainder"
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mla \remainder, \inv, \neg, \numerator
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.ifnc "", "\quotient"
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mov \quotient, \inv
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cmn \remainder, \neg
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subcs \remainder, \remainder, \neg
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addpl \remainder, \remainder, \neg, lsl #1
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addcc \quotient, \quotient, #1
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addpl \quotient, \quotient, #2
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.else
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cmn \remainder, \neg
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subcs \remainder, \remainder, \neg
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addpl \remainder, \remainder, \neg, lsl #1
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.endif
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.else
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mla \divisor, \inv, \neg, \numerator
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mov \quotient, \inv
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cmn \divisor, \neg
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addcc \quotient, \quotient, #1
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addpl \quotient, \quotient, #2
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.endif
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.if \return
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bx lr
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.else
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b 99f
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.endif
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10:
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/* Very large divisors can be handled without further improving the
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reciprocal. First the reciprocal must be reduced to ensure that it
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underestimates the correct value. */
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rsb \bits, \bits, #0
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sub \inv, \inv, #4
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mov \divisor, \inv, lsr \bits
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/* Calculate approximate quotient and remainder */
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umull \bits, \inv, \numerator, \divisor
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/* Correct quotient and remainder */
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.ifnc "", "\remainder"
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mla \remainder, \inv, \neg, \numerator
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.ifnc "", "\quotient"
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mov \quotient, \inv
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cmn \neg, \remainder, lsr #1
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addcs \remainder, \remainder, \neg, lsl #1
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addcs \quotient, \quotient, #2
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cmn \neg, \remainder
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addcs \remainder, \remainder, \neg
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addcs \quotient, \quotient, #1
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.else
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cmn \neg, \remainder, lsr #1
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addcs \remainder, \remainder, \neg, lsl #1
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cmn \neg, \remainder
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addcs \remainder, \remainder, \neg
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.endif
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.else
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mla \divisor, \inv, \neg, \numerator
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mov \quotient, \inv
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cmn \neg, \divisor, lsr #1
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addcs \divisor, \divisor, \neg, lsl #1
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addcs \quotient, \quotient, #2
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cmn \neg, \divisor
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addcs \quotient, \quotient, #1
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.endif
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.if \return
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bx lr
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.else
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b 99f
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.endif
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20:
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/* Handle division by powers of two by shifting right. Mod is handled
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by using divisor-1 as a bitmask. */
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.ifnc "", "\remainder"
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.ifnc "", "\div0label"
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bne \div0label
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.endif
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.ifnc "", "\quotient"
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sub \divisor, \divisor, #1
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rsb \bits, \bits, #31
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and \remainder, \numerator, \divisor
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mov \quotient, \numerator, lsr \bits
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.else
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sub \divisor, \divisor, #1
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and \remainder, \numerator, \divisor
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.endif
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.else
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rsb \bits, \bits, #31
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.ifnc "", "\div0label"
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bne \div0label
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.endif
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mov \quotient, \numerator, lsr \bits
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.endif
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.if \return
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bx lr
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.else
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b 99f
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|
|
|
.endif
|
|
|
|
30:
|
|
|
|
/* Handle numerator < divisor - quotient is zero, remainder is numerator,
|
|
|
|
which must be restored to its original value on ARMv6. */
|
|
|
|
.ifnc "", "\remainder"
|
|
|
|
mov \remainder, \numerator
|
|
|
|
.endif
|
|
|
|
.ifnc "", "\quotient"
|
|
|
|
mov \quotient, #0
|
|
|
|
.endif
|
|
|
|
.if \return
|
|
|
|
bx lr
|
|
|
|
.endif
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
40:
|
|
|
|
/* Handle large (sign bit set) numerators. Works exactly as the ARMv5e code
|
|
|
|
above 10:. */
|
|
|
|
umull \bits, \inv, \numerator, \divisor
|
|
|
|
add \numerator, \numerator, \neg
|
|
|
|
.ifnc "", "\remainder"
|
|
|
|
mla \remainder, \inv, \neg, \numerator
|
|
|
|
.ifnc "", "\quotient"
|
|
|
|
mla \remainder, \inv, \neg, \numerator
|
|
|
|
mov \quotient, \inv
|
|
|
|
cmn \remainder, \neg
|
|
|
|
subcs \remainder, \remainder, \neg
|
|
|
|
addpl \remainder, \remainder, \neg, lsl #1
|
|
|
|
addcc \quotient, \quotient, #1
|
|
|
|
addpl \quotient, \quotient, #2
|
|
|
|
.else
|
|
|
|
cmn \remainder, \neg
|
|
|
|
subcs \remainder, \remainder, \neg
|
|
|
|
addpl \remainder, \remainder, \neg, lsl #1
|
|
|
|
.endif
|
|
|
|
.else
|
|
|
|
mla \divisor, \inv, \neg, \numerator
|
|
|
|
mov \quotient, \inv
|
|
|
|
cmn \divisor, \neg
|
|
|
|
addcc \quotient, \quotient, #1
|
|
|
|
addpl \quotient, \quotient, #2
|
|
|
|
.endif
|
|
|
|
.if \return
|
|
|
|
bx lr
|
|
|
|
.else
|
|
|
|
b 99f
|
|
|
|
.endif
|
|
|
|
#endif
|
|
|
|
99:
|
|
|
|
.endm
|
|
|
|
|
|
|
|
.macro ARMV5_SDIV32_BODY numerator, divisor, quotient, remainder, bits, inv, neg, sign, div0label, return
|
|
|
|
/* sign[31] = divisor sign */
|
|
|
|
ands \sign, \divisor, #1<<31
|
|
|
|
rsbne \divisor, \divisor, #0
|
|
|
|
/* sign[31] = result sign, sign[0:30], C = numerator sign */
|
|
|
|
eors \sign, \sign, \numerator, asr #32
|
|
|
|
clz \bits, \divisor
|
|
|
|
rsbcs \numerator, \numerator, #0
|
|
|
|
/* On ARMv6, subtract divisor before performing division, which ensures
|
|
|
|
numerator sign bit is clear and smmul may be used in place of umull. The
|
|
|
|
fixup for the results can be fit entirely into existing delay slots on
|
|
|
|
the main division paths. It costs 1c in the num<div path if the
|
|
|
|
the remainder is to be produced in the numerator's register, and 1c in
|
|
|
|
the power-of-2-divisor path only if producing both remainder and
|
|
|
|
quotient. */
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
subs \numerator, \numerator, \divisor
|
|
|
|
#else
|
|
|
|
cmp \numerator, \divisor
|
|
|
|
#endif
|
|
|
|
movcs \inv, \divisor, lsl \bits
|
|
|
|
bcc 30f
|
|
|
|
/* Test whether divisor is 2^N */
|
|
|
|
cmp \inv, #1<<31
|
|
|
|
add \inv, pc, \inv, lsr #25
|
|
|
|
bls 20f
|
|
|
|
/* Load approximate reciprocal */
|
|
|
|
ldrb \inv, [\inv, #.L_udiv_est_table-.-64]
|
|
|
|
subs \bits, \bits, #7
|
|
|
|
rsb \neg, \divisor, #0
|
|
|
|
/* Scale approximate reciprocal, or else branch to large-divisor path */
|
|
|
|
movpl \divisor, \inv, lsl \bits
|
|
|
|
bmi 10f
|
|
|
|
/* Newton-Raphson iteration to improve reciprocal accuracy */
|
|
|
|
mul \inv, \divisor, \neg
|
|
|
|
smlawt \divisor, \divisor, \inv, \divisor
|
|
|
|
mul \inv, \divisor, \neg
|
|
|
|
/* Complete N-R math and produce approximate quotient. Use smmla/smmul on
|
|
|
|
ARMv6. */
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
smmla \divisor, \divisor, \inv, \divisor
|
|
|
|
smmul \inv, \numerator, \divisor
|
|
|
|
#else
|
|
|
|
mov \bits, #0
|
|
|
|
smlal \bits, \divisor, \inv, \divisor
|
|
|
|
umull \bits, \inv, \numerator, \divisor
|
|
|
|
#endif
|
|
|
|
/* Calculate remainder and correct quotient. */
|
|
|
|
add \numerator, \numerator, \neg
|
|
|
|
.ifnc "", "\remainder"
|
|
|
|
mla \remainder, \inv, \neg, \numerator
|
|
|
|
.ifnc "", "\quotient"
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \quotient, \inv, #1
|
|
|
|
#else
|
|
|
|
mov \quotient, \inv
|
|
|
|
#endif
|
|
|
|
cmn \remainder, \neg
|
|
|
|
subcs \remainder, \remainder, \neg
|
|
|
|
addpl \remainder, \remainder, \neg, lsl #1
|
|
|
|
addcc \quotient, \quotient, #1
|
|
|
|
addpl \quotient, \quotient, #2
|
|
|
|
.else
|
|
|
|
cmn \remainder, \neg
|
|
|
|
subcs \remainder, \remainder, \neg
|
|
|
|
addpl \remainder, \remainder, \neg, lsl #1
|
|
|
|
.endif
|
|
|
|
.else
|
|
|
|
mla \divisor, \inv, \neg, \numerator
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \quotient, \inv, #1
|
|
|
|
#else
|
|
|
|
mov \quotient, \inv
|
|
|
|
#endif
|
|
|
|
cmn \divisor, \neg
|
|
|
|
addcc \quotient, \quotient, #1
|
|
|
|
addpl \quotient, \quotient, #2
|
|
|
|
.endif
|
|
|
|
ARM_SDIV32_POST \quotient, \remainder, \sign
|
|
|
|
.ifnc "", "\return"
|
|
|
|
\return
|
|
|
|
.else
|
|
|
|
b 99f
|
|
|
|
.endif
|
|
|
|
10:
|
|
|
|
/* Very large divisors can be handled without further improving the
|
|
|
|
reciprocal. First the reciprocal must be reduced to ensure that it
|
|
|
|
underestimates the correct value. */
|
|
|
|
rsb \bits, \bits, #0
|
|
|
|
sub \inv, \inv, #4
|
|
|
|
mov \divisor, \inv, lsr \bits
|
|
|
|
/* Calculate approximate quotient and remainder */
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
smmul \inv, \numerator, \divisor
|
|
|
|
#else
|
|
|
|
umull \bits, \inv, \numerator, \divisor
|
|
|
|
#endif
|
|
|
|
/* Correct quotient and remainder */
|
|
|
|
.ifnc "", "\remainder"
|
|
|
|
mla \remainder, \inv, \neg, \numerator
|
|
|
|
.ifnc "", "\quotient"
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \quotient, \inv, #1
|
|
|
|
#else
|
|
|
|
mov \quotient, \inv
|
|
|
|
#endif
|
|
|
|
cmn \neg, \remainder, lsr #1
|
|
|
|
addcs \remainder, \remainder, \neg, lsl #1
|
|
|
|
addcs \quotient, \quotient, #2
|
|
|
|
cmn \neg, \remainder
|
|
|
|
addcs \remainder, \remainder, \neg
|
|
|
|
addcs \quotient, \quotient, #1
|
|
|
|
.else
|
|
|
|
cmn \neg, \remainder, lsr #1
|
|
|
|
addcs \remainder, \remainder, \neg, lsl #1
|
|
|
|
cmn \neg, \remainder
|
|
|
|
addcs \remainder, \remainder, \neg
|
|
|
|
.endif
|
|
|
|
.else
|
|
|
|
mla \divisor, \inv, \neg, \numerator
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \quotient, \inv, #1
|
|
|
|
#else
|
|
|
|
mov \quotient, \inv
|
|
|
|
#endif
|
|
|
|
cmn \neg, \divisor, lsr #1
|
|
|
|
addcs \divisor, \divisor, \neg, lsl #1
|
|
|
|
addcs \quotient, \quotient, #2
|
|
|
|
cmn \neg, \divisor
|
|
|
|
addcs \quotient, \quotient, #1
|
|
|
|
.endif
|
|
|
|
ARM_SDIV32_POST \quotient, \remainder, \sign
|
|
|
|
.ifnc "", "\return"
|
|
|
|
\return
|
|
|
|
.else
|
|
|
|
b 99f
|
|
|
|
.endif
|
|
|
|
20:
|
|
|
|
/* Handle division by powers of two by shifting right. Mod is handled
|
|
|
|
by using divisor-1 as a bitmask. */
|
|
|
|
.ifnc "", "\div0label"
|
|
|
|
bne \div0label
|
|
|
|
.endif
|
|
|
|
.ifnc "", "\remainder"
|
|
|
|
.ifnc "", "\quotient"
|
|
|
|
rsb \bits, \bits, #31
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \numerator, \numerator, \divisor
|
|
|
|
#endif
|
|
|
|
sub \divisor, \divisor, #1
|
|
|
|
and \remainder, \numerator, \divisor
|
|
|
|
mov \quotient, \numerator, lsr \bits
|
|
|
|
.else
|
|
|
|
sub \divisor, \divisor, #1
|
|
|
|
and \remainder, \numerator, \divisor
|
|
|
|
.endif
|
|
|
|
.else
|
|
|
|
rsb \bits, \bits, #31
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \numerator, \numerator, \divisor
|
|
|
|
#endif
|
|
|
|
mov \quotient, \numerator, lsr \bits
|
|
|
|
.endif
|
|
|
|
ARM_SDIV32_POST \quotient, \remainder, \sign
|
|
|
|
.ifnc "", "\return"
|
|
|
|
\return
|
|
|
|
.else
|
|
|
|
b 99f
|
|
|
|
.endif
|
|
|
|
30:
|
|
|
|
/* Handle numerator < divisor - quotient is zero, remainder is numerator,
|
|
|
|
which must be restored to its original value on ARMv6. */
|
|
|
|
.ifnc "", "\remainder"
|
|
|
|
#if ARM_ARCH >= 6
|
|
|
|
add \remainder, \numerator, \divisor
|
|
|
|
#else
|
|
|
|
.ifnc "\remainder", "\numerator"
|
|
|
|
mov \remainder, \numerator
|
|
|
|
.endif
|
|
|
|
#endif
|
|
|
|
.endif
|
|
|
|
.ifnc "", "\quotient"
|
|
|
|
mov \quotient, #0
|
|
|
|
.endif
|
2010-02-02 15:55:10 +00:00
|
|
|
.ifnc "", "\remainder"
|
2010-02-01 01:36:46 +00:00
|
|
|
ARM_SDIV32_POST "", \remainder, \sign
|
2010-02-02 15:55:10 +00:00
|
|
|
.endif
|
2010-02-01 01:36:46 +00:00
|
|
|
.ifnc "", "\return"
|
|
|
|
\return
|
|
|
|
.endif
|
|
|
|
99:
|
|
|
|
.endm
|
2010-02-01 02:35:28 +00:00
|
|
|
#endif
|
2010-02-01 01:36:46 +00:00
|
|
|
|
|
|
|
.section .text
|
|
|
|
|
|
|
|
__div0_wrap_s:
|
|
|
|
sub sp, sp, #4
|
|
|
|
mov r0, #0
|
|
|
|
b __div0
|
|
|
|
.size __div0_wrap_s, . - __div0_wrap_s
|
|
|
|
|
|
|
|
__div0_wrap:
|
|
|
|
str lr, [sp, #-4]!
|
|
|
|
mov r0, #0
|
|
|
|
b __div0
|
|
|
|
.size __div0_wrap, . - __div0_wrap
|
|
|
|
|
|
|
|
#ifndef __ARM_EABI__
|
|
|
|
.global __divsi3
|
|
|
|
.type __divsi3,%function
|
2010-02-02 15:55:10 +00:00
|
|
|
.global __udivsi3
|
|
|
|
.type __udivsi3,%function
|
2010-02-01 01:36:46 +00:00
|
|
|
.global __udivsi3
|
|
|
|
.type __udivsi3,%function
|
|
|
|
#else
|
|
|
|
/* The div+mod averagess a fraction of a cycle worse for signed values, and
|
|
|
|
slightly better for unsigned, so just alias div to divmod. */
|
|
|
|
.global __aeabi_uidivmod
|
|
|
|
.type __aeabi_uidivmod,%function
|
|
|
|
.global __aeabi_uidiv
|
|
|
|
.type __aeabi_uidiv,%function
|
|
|
|
.set __aeabi_uidiv,__aeabi_uidivmod
|
|
|
|
.global __aeabi_idivmod
|
|
|
|
.type __aeabi_idivmod,%function
|
|
|
|
.global __aeabi_idiv
|
|
|
|
.type __aeabi_idiv,%function
|
|
|
|
.set __aeabi_idiv,__aeabi_idivmod
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
|
|
#if ARM_ARCH < 5
|
|
|
|
.global __clzsi2
|
|
|
|
.type __clzsi2, %function
|
|
|
|
|
|
|
|
__clzsi2:
|
|
|
|
orr r0, r0, r0, lsr #8
|
|
|
|
orr r0, r0, r0, lsr #4
|
|
|
|
orr r0, r0, r0, lsr #2
|
|
|
|
orr r0, r0, r0, lsr #1
|
|
|
|
bic r0, r0, r0, lsr #16
|
|
|
|
rsb r0, r0, r0, lsl #14
|
|
|
|
rsb r0, r0, r0, lsl #11
|
|
|
|
rsb r0, r0, r0, lsl #9
|
|
|
|
ldrb r0, [pc, r0, lsr #26]
|
|
|
|
bx lr
|
|
|
|
.byte 32, 20, 19, 0, 0, 18, 0, 7, 10, 17, 0, 0, 14, 0, 6, 0
|
|
|
|
.byte 0, 9, 0, 16, 0, 0, 1, 26, 0, 13, 0, 0, 24, 5, 0, 0
|
|
|
|
.byte 0, 21, 0, 8, 11, 0, 15, 0, 0, 0, 0, 2, 27, 0, 25, 0
|
|
|
|
.byte 22, 0, 12, 0, 0, 3, 28, 0, 23, 0, 4, 29, 0, 0, 30, 31
|
|
|
|
.size __clzsi2, .-__clzsi2
|
|
|
|
|
|
|
|
#ifndef __ARM_EABI__
|
|
|
|
__udivsi3:
|
|
|
|
ARMV4_UDIV32_BODY r0, r1, r0, "", r2, r3, __div0_wrap, 1
|
|
|
|
.size __udivsi3, . - __udivsi3
|
|
|
|
|
|
|
|
__divsi3:
|
|
|
|
ARMV4_SDIV32_BODY r0, r1, r0, "", r2, r3, __div0_wrap, 1
|
|
|
|
.size __divsi3, . - __divsi3
|
|
|
|
|
|
|
|
#else
|
|
|
|
__aeabi_uidivmod:
|
|
|
|
ARMV4_UDIV32_BODY r0, r1, r0, r1, r2, r3, __div0_wrap, 1
|
|
|
|
.size __aeabi_uidivmod, . - __aeabi_uidivmo
|
|
|
|
|
2010-02-01 02:35:35 +00:00
|
|
|
__aeabi_idivmod:
|
2010-02-01 01:36:46 +00:00
|
|
|
ARMV4_SDIV32_BODY r0, r1, r0, r1, r2, r3, __div0_wrap, 1
|
|
|
|
.size __aeabi_idivmod, . - __aeabi_idivmod
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#else
|
|
|
|
#ifndef __ARM_EABI__
|
|
|
|
__udivsi3:
|
|
|
|
ARMV5_UDIV32_BODY r0, r1, r0, "", r2, r3, ip, __div0_wrap, 1
|
|
|
|
.size __udivsi3, . - __udivsi3
|
|
|
|
|
|
|
|
__divsi3:
|
2010-02-02 15:55:10 +00:00
|
|
|
str lr, [sp, #-4]
|
2010-02-01 01:36:46 +00:00
|
|
|
ARMV5_SDIV32_BODY r0, r1, r0, "", r2, lr, ip, r3, __div0_wrap_s, "ldr pc, [sp, #-4]"
|
|
|
|
.size __divsi3, . - __divsi3
|
|
|
|
|
|
|
|
#else
|
|
|
|
__aeabi_uidivmod:
|
|
|
|
ARMV5_UDIV32_BODY r0, r1, r0, r1, r2, r3, ip, __div0_wrap, 1
|
|
|
|
.size __aeabi_uidivmod, . - __aeabi_uidivmo
|
|
|
|
|
2010-02-01 02:35:35 +00:00
|
|
|
__aeabi_idivmod:
|
2010-02-02 15:55:10 +00:00
|
|
|
str lr, [sp, #-4]
|
2010-02-01 01:36:46 +00:00
|
|
|
ARMV5_SDIV32_BODY r0, r1, r0, r1, r2, lr, ip, r3, __div0_wrap_s, "ldr pc, [sp, #-4]"
|
|
|
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.size __aeabi_idivmod, . - __aeabi_idivmod
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#endif
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.L_udiv_est_table:
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.byte 0xff, 0xfc, 0xf8, 0xf4, 0xf0, 0xed, 0xea, 0xe6
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.byte 0xe3, 0xe0, 0xdd, 0xda, 0xd7, 0xd4, 0xd2, 0xcf
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.byte 0xcc, 0xca, 0xc7, 0xc5, 0xc3, 0xc0, 0xbe, 0xbc
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.byte 0xba, 0xb8, 0xb6, 0xb4, 0xb2, 0xb0, 0xae, 0xac
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.byte 0xaa, 0xa8, 0xa7, 0xa5, 0xa3, 0xa2, 0xa0, 0x9f
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.byte 0x9d, 0x9c, 0x9a, 0x99, 0x97, 0x96, 0x94, 0x93
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.byte 0x92, 0x90, 0x8f, 0x8e, 0x8d, 0x8c, 0x8a, 0x89
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.byte 0x88, 0x87, 0x86, 0x85, 0x84, 0x83, 0x82, 0x81
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#endif
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