diff options
Diffstat (limited to 'gmp/mpn/thumb/sub_n.asm')
| -rw-r--r-- | gmp/mpn/thumb/sub_n.asm | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/gmp/mpn/thumb/sub_n.asm b/gmp/mpn/thumb/sub_n.asm new file mode 100644 index 0000000000..a38572048e --- /dev/null +++ b/gmp/mpn/thumb/sub_n.asm @@ -0,0 +1,63 @@ +dnl ARM/Thumb mpn_sub_n. + +dnl Copyright 1997, 2000, 2012 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/. + +include(`../config.m4') + +C INPUT PARAMETERS +define(`rp', r0) +define(`up', r1) +define(`vp', r2) +define(`n', r3) + +ASM_START() + .thumb +PROLOGUE(mpn_sub_nc) + push {r4, r5, r6} + ldr r6, [sp, #12] C init carry save register + neg r6, r6 + b L(top) +EPILOGUE() +PROLOGUE(mpn_sub_n) + push {r4, r5, r6} + mov r6, n C init carry save register + +L(top): ldmia up!, {r4} C load next limb from S1 + cmp n, r6 C tricky carry restore + ldmia vp!, {r5} C load next limb from S2 + sbc r4, r5 + stmia rp!, {r4} C store result limb to RES + sbc r6, r6 C save negated carry + sub n, #1 + bne L(top) + + neg r0, r6 + pop {r4, r5, r6} + bx lr +EPILOGUE() |