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###################################

#

#  Copyright 2009, 2010, 2011 Free Software Foundation, Inc.

#

#  Contributed by Michael Eager .

#

#  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.

#

#  GCC 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

#  .

#

#  umodsi3.S

#

#  Unsigned modulo operation for 32 bit integers.

#       Input : op1 in Reg r5

#               op2 in Reg r6

#       Output: op1 mod op2 in Reg r3

#

#######################################

        .globl  __umodsi3

        .ent    __umodsi3

        .type   __umodsi3,@function

__umodsi3:

        .frame  r1,0,r15

        addik   r1,r1,-12

        swi     r29,r1,0

        swi     r30,r1,4

        swi     r31,r1,8

        BEQI    r6,$LaDiv_By_Zero         # Div_by_Zero   # Division Error

        BEQId   r5,$LaResult_Is_Zero     # Result is Zero

        ADDIK   r3,r0,0                  # Clear div

        ADDIK   r30,r0,0        # clear mod

        ADDIK   r29,r0,32       # Initialize the loop count

# Check if r6 and r5 are equal # if yes, return 0

        rsub    r18,r5,r6

        beqi    r18,$LaRETURN_HERE

# Check if (uns)r6 is greater than (uns)r5. In that case, just return r5

        xor     r18,r5,r6

        bgeid   r18,16

        addik   r3,r5,0

        blti    r6,$LaRETURN_HERE

        bri     $LCheckr6

        rsub    r18,r5,r6 # MICROBLAZEcmp

        bgti    r18,$LaRETURN_HERE

# If r6 [bit 31] is set, then return result as r5-r6

$LCheckr6:

        bgtid   r6,$LaDIV0

        addik   r3,r0,0

        addik   r18,r0,0x7fffffff

        and     r5,r5,r18

        and     r6,r6,r18

        brid    $LaRETURN_HERE

        rsub    r3,r6,r5

# First part: try to find the first '1' in the r5

$LaDIV0:

        BLTI    r5,$LaDIV2

$LaDIV1:

        ADD     r5,r5,r5     # left shift logical r5

        BGEID   r5,$LaDIV1   #

        ADDIK   r29,r29,-1

$LaDIV2:

        ADD     r5,r5,r5     # left shift logical  r5 get the '1' into the Carry

        ADDC    r3,r3,r3     # Move that bit into the Mod register

        rSUB    r31,r6,r3    # Try to subtract (r3 a r6)

        BLTi    r31,$LaMOD_TOO_SMALL

        OR      r3,r0,r31    # Move the r31 to mod since the result was positive

        ADDIK   r30,r30,1

$LaMOD_TOO_SMALL:

        ADDIK   r29,r29,-1

        BEQi    r29,$LaLOOP_END

        ADD     r30,r30,r30 # Shift in the '1' into div

        BRI     $LaDIV2     # Div2

$LaLOOP_END:

        BRI     $LaRETURN_HERE

$LaDiv_By_Zero:

$LaResult_Is_Zero:

        or      r3,r0,r0   # set result to 0

$LaRETURN_HERE:

# Restore values of CSRs and that of r3 and the divisor and the dividend

        lwi     r29,r1,0

        lwi     r30,r1,4

        lwi     r31,r1,8

        rtsd    r15,8

        addik   r1,r1,12

.end __umodsi3

        .size   __umodsi3, . - __umodsi3