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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

#  .

#

#  udivsi3.S

#

#  Unsigned divide operation.

#       Input : Divisor in Reg r5

#               Dividend in Reg r6

#       Output: Result in Reg r3

#

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

        .globl  __udivsi3

        .ent    __udivsi3

        .type   __udivsi3,@function

__udivsi3:

        .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   r30,r0,0                    # Clear mod

        ADDIK   r29,r0,32                   # Initialize the loop count

        # Check if r6 and r5 are equal # if yes, return 1

        RSUB    r18,r5,r6

        BEQID   r18,$LaRETURN_HERE

        ADDIK   r3,r0,1

        # Check if (uns)r6 is greater than (uns)r5. In that case, just return 0

        XOR     r18,r5,r6

        BGEID   r18,16

        ADD     r3,r0,r0                    # We would anyways clear r3

        BLTI    r6,$LaRETURN_HERE           # r6[bit 31 = 1] hence is greater

        BRI     $LCheckr6

        RSUB    r18,r6,r5                   # MICROBLAZEcmp

        BLTI    r18,$LaRETURN_HERE

        # If r6 [bit 31] is set, then return result as 1

$LCheckr6:

        BGTI    r6,$LaDIV0

        BRID    $LaRETURN_HERE

        ADDIK   r3,r0,1

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

$LaDIV0:

        BLTI    r5,$LaDIV2

$LaDIV1:

        ADD     r5,r5,r5                    # left shift logical r5

        BGTID   r5,$LaDIV1

        ADDIK   r29,r29,-1

$LaDIV2:

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

        ADDC    r30,r30,r30                 # Move that bit into the Mod register

        RSUB    r31,r6,r30                  # Try to subtract (r30 a r6)

        BLTI    r31,$LaMOD_TOO_SMALL

        OR      r30,r0,r31                  # Move the r31 to mod since the result was positive

        ADDIK   r3,r3,1

$LaMOD_TOO_SMALL:

        ADDIK   r29,r29,-1

        BEQi    r29,$LaLOOP_END

        ADD     r3,r3,r3 # 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 __udivsi3

        .size   __udivsi3, . - __udivsi3