| dnl ARM64 mpn_invert_limb -- Invert a normalized limb. |
| |
| dnl Contributed to the GNU project by Torbjรถrn Granlund. |
| |
| dnl Copyright 2013 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 cycles/limb |
| C Cortex-A53 ? |
| C Cortex-A57 ? |
| |
| C Compiler generated, mildly edited. Could surely be further optimised. |
| |
| ASM_START() |
| PROLOGUE(mpn_invert_limb) |
| lsr x2, x0, #54 |
| adrp x1, approx_tab |
| and x2, x2, #0x1fe |
| add x1, x1, :lo12:approx_tab |
| ldrh w3, [x1,x2] |
| lsr x4, x0, #24 |
| add x4, x4, #1 |
| ubfiz x2, x3, #11, #16 |
| umull x3, w3, w3 |
| mul x3, x3, x4 |
| sub x2, x2, #1 |
| sub x2, x2, x3, lsr #40 |
| lsl x3, x2, #60 |
| mul x1, x2, x2 |
| msub x1, x1, x4, x3 |
| lsl x2, x2, #13 |
| add x1, x2, x1, lsr #47 |
| and x2, x0, #1 |
| neg x3, x2 |
| and x3, x3, x1, lsr #1 |
| add x2, x2, x0, lsr #1 |
| msub x2, x1, x2, x3 |
| umulh x2, x2, x1 |
| lsl x1, x1, #31 |
| add x1, x1, x2, lsr #1 |
| mul x3, x1, x0 |
| umulh x2, x1, x0 |
| adds x4, x3, x0 |
| adc x0, x2, x0 |
| sub x0, x1, x0 |
| ret |
| EPILOGUE() |
| |
| RODATA |
| ALIGN(2) |
| TYPE( approx_tab, object) |
| SIZE( approx_tab, 512) |
| approx_tab: |
| forloop(i,256,512-1,dnl |
| ` .hword eval(0x7fd00/i) |
| ')dnl |
