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- ; mc88100 __mpn_add -- Add two limb vectors of the same length > 0 and store
- ; sum in a third limb vector.
-
- ; Copyright (C) 1992, 1994 Free Software Foundation, Inc.
-
- ; This file is part of the GNU MP Library.
-
- ; The GNU MP Library 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 2, or (at your option)
- ; any later version.
-
- ; The GNU MP Library 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.
-
- ; You should have received a copy of the GNU General Public License
- ; along with the GNU MP Library; see the file COPYING. If not, write to
- ; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
-
-
- ; INPUT PARAMETERS
- ; res_ptr r2
- ; s1_ptr r3
- ; s2_ptr r4
- ; size r5
-
- ; This code has been optimized to run one instruction per clock, avoiding
- ; load stalls and writeback contention. As a result, the instruction
- ; order is not always natural.
-
- ; The speed is approximately 4.3 clocks/limb + 18 clocks/limb-vector.
-
- #include "sysdep.h"
-
- ENTRY (__mpn_add_n)
- ld r6,r3,0 ; read first limb from s1_ptr
- extu r10,r5,4
- ld r7,r4,0 ; read first limb from s2_ptr
-
- subu.co r5,r0,r5 ; (clear carry as side effect)
- mak r5,r5,4<4>
- bcnd eq0,r5,Lzero
-
- or r12,r0,lo16(Lbase)
- or.u r12,r12,hi16(Lbase)
- addu r12,r12,r5 ; r12 is address for entering in loop
-
- extu r5,r5,2 ; divide by 4
- subu r2,r2,r5 ; adjust res_ptr
- subu r3,r3,r5 ; adjust s1_ptr
- subu r4,r4,r5 ; adjust s2_ptr
-
- or r8,r6,r0
-
- jmp.n r12
- or r9,r7,r0
-
- Loop: addu r3,r3,64
- st r8,r2,60
- addu r4,r4,64
- ld r6,r3,0
- addu r2,r2,64
- ld r7,r4,0
- Lzero: subu r10,r10,1 ; add 0 + 16r limbs (adjust loop counter)
- Lbase: ld r8,r3,4
- addu.cio r6,r6,r7
- ld r9,r4,4
- st r6,r2,0
- ld r6,r3,8 ; add 15 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,8
- st r8,r2,4
- ld r8,r3,12 ; add 14 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,12
- st r6,r2,8
- ld r6,r3,16 ; add 13 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,16
- st r8,r2,12
- ld r8,r3,20 ; add 12 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,20
- st r6,r2,16
- ld r6,r3,24 ; add 11 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,24
- st r8,r2,20
- ld r8,r3,28 ; add 10 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,28
- st r6,r2,24
- ld r6,r3,32 ; add 9 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,32
- st r8,r2,28
- ld r8,r3,36 ; add 8 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,36
- st r6,r2,32
- ld r6,r3,40 ; add 7 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,40
- st r8,r2,36
- ld r8,r3,44 ; add 6 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,44
- st r6,r2,40
- ld r6,r3,48 ; add 5 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,48
- st r8,r2,44
- ld r8,r3,52 ; add 4 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,52
- st r6,r2,48
- ld r6,r3,56 ; add 3 + 16r limbs
- addu.cio r8,r8,r9
- ld r7,r4,56
- st r8,r2,52
- ld r8,r3,60 ; add 2 + 16r limbs
- addu.cio r6,r6,r7
- ld r9,r4,60
- st r6,r2,56
- bcnd.n ne0,r10,Loop ; add 1 + 16r limbs
- addu.cio r8,r8,r9
-
- st r8,r2,60 ; store most significant limb
-
- jmp.n r1
- addu.ci r2,r0,r0 ; return carry-out from most sign. limb
-