1 ###################################-
3 # Copyright 2009, 2010, 2011 Free Software Foundation, Inc.
5 # Contributed by Michael Eager <eager@eagercon.com>.
7 # This file is free software; you can redistribute it and/or modify it
8 # under the terms of the GNU General Public License as published by the
9 # Free Software Foundation; either version 3, or (at your option) any
12 # GCC is distributed in the hope that it will be useful, but WITHOUT
13 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
15 # License for more details.
17 # Under Section 7 of GPL version 3, you are granted additional
18 # permissions described in the GCC Runtime Library Exception, version
19 # 3.1, as published by the Free Software Foundation.
21 # You should have received a copy of the GNU General Public License and
22 # a copy of the GCC Runtime Library Exception along with this program;
23 # see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
24 # <http://www.gnu.org/licenses/>.
28 # Unsigned divide operation.
29 # Input : Divisor in Reg r5
31 # Output: Result in Reg r3
33 #######################################
37 .type __udivsi3,@function
46 BEQI r6,$LaDiv_By_Zero # Div_by_Zero # Division Error
47 BEQID r5,$LaResult_Is_Zero # Result is Zero
48 ADDIK r30,r0,0 # Clear mod
49 ADDIK r29,r0,32 # Initialize the loop count
51 # Check if r6 and r5 are equal # if yes, return 1
53 BEQID r18,$LaRETURN_HERE
56 # Check if (uns)r6 is greater than (uns)r5. In that case, just return 0
59 ADD r3,r0,r0 # We would anyways clear r3
60 BLTI r6,$LaRETURN_HERE # r6[bit 31 = 1] hence is greater
62 RSUB r18,r6,r5 # MICROBLAZEcmp
63 BLTI r18,$LaRETURN_HERE
65 # If r6 [bit 31] is set, then return result as 1
71 # First part try to find the first '1' in the r5
75 ADD r5,r5,r5 # left shift logical r5
79 ADD r5,r5,r5 # left shift logical r5 get the '1' into the Carry
80 ADDC r30,r30,r30 # Move that bit into the Mod register
81 RSUB r31,r6,r30 # Try to subtract (r30 a r6)
82 BLTI r31,$LaMOD_TOO_SMALL
83 OR r30,r0,r31 # Move the r31 to mod since the result was positive
88 ADD r3,r3,r3 # Shift in the '1' into div
94 OR r3,r0,r0 # set result to 0
96 # Restore values of CSRs and that of r3 and the divisor and the dividend
103 .size __udivsi3, . - __udivsi3