| ################################### |
| # |
| # Copyright (C) 2009-2021 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/>. |
| # |
| # modsi3.S |
| # |
| # modulo operation for 64 bit integers. |
| # |
| ####################################### |
| |
| |
| /* An executable stack is *not* required for these functions. */ |
| #ifdef __linux__ |
| .section .note.GNU-stack,"",%progbits |
| .previous |
| #endif |
| |
| .globl __moddi3 |
| .ent __moddi3 |
| __moddi3: |
| .frame r1,0,r15 |
| |
| #Change the stack pointer value and Save callee saved regs |
| addik r1,r1,-24 |
| swi r25,r1,0 |
| swi r26,r1,4 |
| swi r27,r1,8 # used for sign |
| swi r28,r1,12 # used for loop count |
| swi r29,r1,16 # Used for div value High |
| swi r30,r1,20 # Used for div value Low |
| |
| #Check for Zero Value in the divisor/dividend |
| OR r9,r5,r6 # Check for the op1 being zero |
| BEQID r9,$LaResult_Is_Zero # Result is zero |
| OR r9,r7,r8 # Check for the dividend being zero |
| BEQI r9,$LaDiv_By_Zero # Div_by_Zero # Division Error |
| BGEId r5,$La1_Pos |
| XOR r27,r5,r7 # Get the sign of the result |
| RSUBI r6,r6,0 # Make dividend positive |
| RSUBIC r5,r5,0 # Make dividend positive |
| $La1_Pos: |
| BGEI r7,$La2_Pos |
| RSUBI r8,r8,0 # Make Divisor Positive |
| RSUBIC r9,r9,0 # Make Divisor Positive |
| $La2_Pos: |
| ADDIK r4,r0,0 # Clear mod low |
| ADDIK r3,r0,0 # Clear mod high |
| ADDIK r29,r0,0 # clear div high |
| ADDIK r30,r0,0 # clear div low |
| ADDIK r28,r0,64 # Initialize the loop count |
| # First part try to find the first '1' in the r5/r6 |
| $LaDIV1: |
| ADD r6,r6,r6 |
| ADDC r5,r5,r5 # left shift logical r5 |
| BGEID r5,$LaDIV1 |
| ADDIK r28,r28,-1 |
| $LaDIV2: |
| ADD r6,r6,r6 |
| ADDC r5,r5,r5 # left shift logical r5/r6 get the '1' into the Carry |
| ADDC r4,r4,r4 # Move that bit into the Mod register |
| ADDC r3,r3,r3 # Move carry into high mod register |
| rsub r18,r7,r3 # Compare the High Parts of Mod and Divisor |
| bnei r18,$L_High_EQ |
| rsub r18,r6,r4 # Compare Low Parts only if Mod[h] == Divisor[h] |
| $L_High_EQ: |
| rSUB r26,r8,r4 # Subtract divisor[L] from Mod[L] |
| rsubc r25,r7,r3 # Subtract divisor[H] from Mod[H] |
| BLTi r25,$LaMOD_TOO_SMALL |
| OR r3,r0,r25 # move r25 to mod [h] |
| OR r4,r0,r26 # move r26 to mod [l] |
| ADDI r30,r30,1 |
| ADDC r29,r29,r0 |
| $LaMOD_TOO_SMALL: |
| ADDIK r28,r28,-1 |
| BEQi r28,$LaLOOP_END |
| ADD r30,r30,r30 # Shift in the '1' into div [low] |
| ADDC r29,r29,r29 # Move the carry generated into high |
| BRI $LaDIV2 # Div2 |
| $LaLOOP_END: |
| BGEI r27,$LaRETURN_HERE |
| rsubi r30,r30,0 |
| rsubc r29,r29,r0 |
| BRI $LaRETURN_HERE |
| $LaDiv_By_Zero: |
| $LaResult_Is_Zero: |
| or r29,r0,r0 # set result to 0 [High] |
| or r30,r0,r0 # set result to 0 [Low] |
| $LaRETURN_HERE: |
| # Restore values of CSRs and that of r29 and the divisor and the dividend |
| |
| lwi r25,r1,0 |
| lwi r26,r1,4 |
| lwi r27,r1,8 |
| lwi r28,r1,12 |
| lwi r29,r1,16 |
| lwi r30,r1,20 |
| rtsd r15,8 |
| addik r1,r1,24 |
| .end __moddi3 |
| |
