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Diffstat (limited to 'sysdeps/aarch64/multiarch/memset_base64.S')
| -rw-r--r-- | sysdeps/aarch64/multiarch/memset_base64.S | 185 |
1 files changed, 0 insertions, 185 deletions
diff --git a/sysdeps/aarch64/multiarch/memset_base64.S b/sysdeps/aarch64/multiarch/memset_base64.S deleted file mode 100644 index 0e8f709..0000000 --- a/sysdeps/aarch64/multiarch/memset_base64.S +++ /dev/null @@ -1,185 +0,0 @@ -/* Copyright (C) 2018-2023 Free Software Foundation, Inc. - - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library. If not, see - <https://www.gnu.org/licenses/>. */ - -#include <sysdep.h> -#include "memset-reg.h" - -#ifndef MEMSET -# define MEMSET __memset_base64 -#endif - -/* To disable DC ZVA, set this threshold to 0. */ -#ifndef DC_ZVA_THRESHOLD -# define DC_ZVA_THRESHOLD 512 -#endif - -/* Assumptions: - * - * ARMv8-a, AArch64, unaligned accesses - * - */ - -ENTRY (MEMSET) - - PTR_ARG (0) - SIZE_ARG (2) - - bfi valw, valw, 8, 8 - bfi valw, valw, 16, 16 - bfi val, val, 32, 32 - - add dstend, dstin, count - - cmp count, 96 - b.hi L(set_long) - cmp count, 16 - b.hs L(set_medium) - - /* Set 0..15 bytes. */ - tbz count, 3, 1f - str val, [dstin] - str val, [dstend, -8] - ret - - .p2align 3 -1: tbz count, 2, 2f - str valw, [dstin] - str valw, [dstend, -4] - ret -2: cbz count, 3f - strb valw, [dstin] - tbz count, 1, 3f - strh valw, [dstend, -2] -3: ret - - .p2align 3 - /* Set 16..96 bytes. */ -L(set_medium): - stp val, val, [dstin] - tbnz count, 6, L(set96) - stp val, val, [dstend, -16] - tbz count, 5, 1f - stp val, val, [dstin, 16] - stp val, val, [dstend, -32] -1: ret - - .p2align 4 - /* Set 64..96 bytes. Write 64 bytes from the start and - 32 bytes from the end. */ -L(set96): - stp val, val, [dstin, 16] - stp val, val, [dstin, 32] - stp val, val, [dstin, 48] - stp val, val, [dstend, -32] - stp val, val, [dstend, -16] - ret - - .p2align 4 -L(set_long): - stp val, val, [dstin] - bic dst, dstin, 15 -#if DC_ZVA_THRESHOLD - cmp count, DC_ZVA_THRESHOLD - ccmp val, 0, 0, cs - b.eq L(zva_64) -#endif - /* Small-size or non-zero memset does not use DC ZVA. */ - sub count, dstend, dst - - /* - * Adjust count and bias for loop. By subtracting extra 1 from count, - * it is easy to use tbz instruction to check whether loop tailing - * count is less than 33 bytes, so as to bypass 2 unnecessary stps. - */ - sub count, count, 64+16+1 - -#if DC_ZVA_THRESHOLD - /* Align loop on 16-byte boundary, this might be friendly to i-cache. */ - nop -#endif - -1: stp val, val, [dst, 16] - stp val, val, [dst, 32] - stp val, val, [dst, 48] - stp val, val, [dst, 64]! - subs count, count, 64 - b.hs 1b - - tbz count, 5, 1f /* Remaining count is less than 33 bytes? */ - stp val, val, [dst, 16] - stp val, val, [dst, 32] -1: stp val, val, [dstend, -32] - stp val, val, [dstend, -16] - ret - -#if DC_ZVA_THRESHOLD - .p2align 3 -L(zva_64): - stp val, val, [dst, 16] - stp val, val, [dst, 32] - stp val, val, [dst, 48] - bic dst, dst, 63 - - /* - * Previous memory writes might cross cache line boundary, and cause - * cache line partially dirty. Zeroing this kind of cache line using - * DC ZVA will incur extra cost, for it requires loading untouched - * part of the line from memory before zeoring. - * - * So, write the first 64 byte aligned block using stp to force - * fully dirty cache line. - */ - stp val, val, [dst, 64] - stp val, val, [dst, 80] - stp val, val, [dst, 96] - stp val, val, [dst, 112] - - sub count, dstend, dst - /* - * Adjust count and bias for loop. By subtracting extra 1 from count, - * it is easy to use tbz instruction to check whether loop tailing - * count is less than 33 bytes, so as to bypass 2 unnecessary stps. - */ - sub count, count, 128+64+64+1 - add dst, dst, 128 - nop - - /* DC ZVA sets 64 bytes each time. */ -1: dc zva, dst - add dst, dst, 64 - subs count, count, 64 - b.hs 1b - - /* - * Write the last 64 byte aligned block using stp to force fully - * dirty cache line. - */ - stp val, val, [dst, 0] - stp val, val, [dst, 16] - stp val, val, [dst, 32] - stp val, val, [dst, 48] - - tbz count, 5, 1f /* Remaining count is less than 33 bytes? */ - stp val, val, [dst, 64] - stp val, val, [dst, 80] -1: stp val, val, [dstend, -32] - stp val, val, [dstend, -16] - ret -#endif - -END (MEMSET) |