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Diffstat (limited to 'gcc-4.9/libgcc/config/microblaze/udivsi3.S')
| -rw-r--r-- | gcc-4.9/libgcc/config/microblaze/udivsi3.S | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/gcc-4.9/libgcc/config/microblaze/udivsi3.S b/gcc-4.9/libgcc/config/microblaze/udivsi3.S new file mode 100644 index 000000000..69cb8eb20 --- /dev/null +++ b/gcc-4.9/libgcc/config/microblaze/udivsi3.S @@ -0,0 +1,103 @@ +###################################- +# +# Copyright (C) 2009-2014 Free Software Foundation, Inc. +# +# Contributed by Michael Eager <eager@eagercon.com>. +# +# 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 +# <http://www.gnu.org/licenses/>. +# +# 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 |