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Diffstat (limited to 'gmp/mpn/power/sub_n.asm')
| -rw-r--r-- | gmp/mpn/power/sub_n.asm | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/gmp/mpn/power/sub_n.asm b/gmp/mpn/power/sub_n.asm new file mode 100644 index 0000000000..390c802d8b --- /dev/null +++ b/gmp/mpn/power/sub_n.asm @@ -0,0 +1,85 @@ +dnl IBM POWER mpn_sub_n -- Subtract two limb vectors of equal, non-zero +dnl length. + +dnl Copyright 1992, 1994-1996, 1999-2001, 2005 Free Software Foundation, Inc. + +dnl This file is part of the GNU MP Library. +dnl +dnl The GNU MP Library is free software; you can redistribute it and/or modify +dnl it under the terms of either: +dnl +dnl * the GNU Lesser General Public License as published by the Free +dnl Software Foundation; either version 3 of the License, or (at your +dnl option) any later version. +dnl +dnl or +dnl +dnl * the GNU General Public License as published by the Free Software +dnl Foundation; either version 2 of the License, or (at your option) any +dnl later version. +dnl +dnl or both in parallel, as here. +dnl +dnl The GNU MP Library is distributed in the hope that it will be useful, but +dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +dnl for more details. +dnl +dnl You should have received copies of the GNU General Public License and the +dnl GNU Lesser General Public License along with the GNU MP Library. If not, +dnl see https://www.gnu.org/licenses/. + + +dnl INPUT PARAMETERS +dnl res_ptr r3 +dnl s1_ptr r4 +dnl s2_ptr r5 +dnl size r6 + +include(`../config.m4') + +ASM_START() +PROLOGUE(mpn_sub_n) + andil. 10,6,1 C odd or even number of limbs? + l 8,0(4) C load least significant s1 limb + l 0,0(5) C load least significant s2 limb + cal 3,-4(3) C offset res_ptr, it's updated before it's used + sri 10,6,1 C count for unrolled loop + sf 7,0,8 C subtract least significant limbs, set cy + mtctr 10 C copy count into CTR + beq 0,Leven C branch if even # of limbs (# of limbs >= 2) + +C We have an odd # of limbs. Add the first limbs separately. + cmpi 1,10,0 C is count for unrolled loop zero? + bc 4,6,L1 C bne cr1,L1 (misassembled by gas) + st 7,4(3) + sfe 3,0,0 C load !cy into ... + sfi 3,3,0 C ... return value register + br C return + +C We added least significant limbs. Now reload the next limbs to enter loop. +L1: lu 8,4(4) C load s1 limb and update s1_ptr + lu 0,4(5) C load s2 limb and update s2_ptr + stu 7,4(3) + sfe 7,0,8 C subtract limbs, set cy +Leven: lu 9,4(4) C load s1 limb and update s1_ptr + lu 10,4(5) C load s2 limb and update s2_ptr + bdz Lend C If done, skip loop + +Loop: lu 8,4(4) C load s1 limb and update s1_ptr + lu 0,4(5) C load s2 limb and update s2_ptr + sfe 11,10,9 C subtract previous limbs with cy, set cy + stu 7,4(3) C + lu 9,4(4) C load s1 limb and update s1_ptr + lu 10,4(5) C load s2 limb and update s2_ptr + sfe 7,0,8 C subtract previous limbs with cy, set cy + stu 11,4(3) C + bdn Loop C decrement CTR and loop back + +Lend: sfe 11,10,9 C subtract limbs with cy, set cy + st 7,4(3) C + st 11,8(3) C + sfe 3,0,0 C load !cy into ... + sfi 3,3,0 C ... return value register + br +EPILOGUE(mpn_sub_n) |