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Diffstat (limited to 'sysdeps/aarch64/memcpy.S')
| -rw-r--r-- | sysdeps/aarch64/memcpy.S | 267 |
1 files changed, 0 insertions, 267 deletions
diff --git a/sysdeps/aarch64/memcpy.S b/sysdeps/aarch64/memcpy.S deleted file mode 100644 index 88a3b90e16..0000000000 --- a/sysdeps/aarch64/memcpy.S +++ /dev/null @@ -1,267 +0,0 @@ -/* Copyright (C) 2012-2017 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 - <http://www.gnu.org/licenses/>. */ - -#include <sysdep.h> - -/* Assumptions: - * - * ARMv8-a, AArch64, unaligned accesses. - * - */ - -#define dstin x0 -#define src x1 -#define count x2 -#define dst x3 -#define srcend x4 -#define dstend x5 -#define A_l x6 -#define A_lw w6 -#define A_h x7 -#define A_hw w7 -#define B_l x8 -#define B_lw w8 -#define B_h x9 -#define C_l x10 -#define C_h x11 -#define D_l x12 -#define D_h x13 -#define E_l src -#define E_h count -#define F_l srcend -#define F_h dst -#define G_l count -#define G_h dst -#define tmp1 x14 - -/* Copies are split into 3 main cases: small copies of up to 16 bytes, - medium copies of 17..96 bytes which are fully unrolled. Large copies - of more than 96 bytes align the destination and use an unrolled loop - processing 64 bytes per iteration. - In order to share code with memmove, small and medium copies read all - data before writing, allowing any kind of overlap. So small, medium - and large backwards memmoves are handled by falling through into memcpy. - Overlapping large forward memmoves use a loop that copies backwards. -*/ - -#ifndef MEMMOVE -# define MEMMOVE memmove -#endif -#ifndef MEMCPY -# define MEMCPY memcpy -#endif - -ENTRY_ALIGN (MEMMOVE, 6) - - DELOUSE (0) - DELOUSE (1) - DELOUSE (2) - - sub tmp1, dstin, src - cmp count, 96 - ccmp tmp1, count, 2, hi - b.lo L(move_long) - - /* Common case falls through into memcpy. */ -END (MEMMOVE) -libc_hidden_builtin_def (MEMMOVE) -ENTRY (MEMCPY) - - DELOUSE (0) - DELOUSE (1) - DELOUSE (2) - - prfm PLDL1KEEP, [src] - add srcend, src, count - add dstend, dstin, count - cmp count, 16 - b.ls L(copy16) - cmp count, 96 - b.hi L(copy_long) - - /* Medium copies: 17..96 bytes. */ - sub tmp1, count, 1 - ldp A_l, A_h, [src] - tbnz tmp1, 6, L(copy96) - ldp D_l, D_h, [srcend, -16] - tbz tmp1, 5, 1f - ldp B_l, B_h, [src, 16] - ldp C_l, C_h, [srcend, -32] - stp B_l, B_h, [dstin, 16] - stp C_l, C_h, [dstend, -32] -1: - stp A_l, A_h, [dstin] - stp D_l, D_h, [dstend, -16] - ret - - .p2align 4 - /* Small copies: 0..16 bytes. */ -L(copy16): - cmp count, 8 - b.lo 1f - ldr A_l, [src] - ldr A_h, [srcend, -8] - str A_l, [dstin] - str A_h, [dstend, -8] - ret - .p2align 4 -1: - tbz count, 2, 1f - ldr A_lw, [src] - ldr A_hw, [srcend, -4] - str A_lw, [dstin] - str A_hw, [dstend, -4] - ret - - /* Copy 0..3 bytes. Use a branchless sequence that copies the same - byte 3 times if count==1, or the 2nd byte twice if count==2. */ -1: - cbz count, 2f - lsr tmp1, count, 1 - ldrb A_lw, [src] - ldrb A_hw, [srcend, -1] - ldrb B_lw, [src, tmp1] - strb A_lw, [dstin] - strb B_lw, [dstin, tmp1] - strb A_hw, [dstend, -1] -2: ret - - .p2align 4 - /* Copy 64..96 bytes. Copy 64 bytes from the start and - 32 bytes from the end. */ -L(copy96): - ldp B_l, B_h, [src, 16] - ldp C_l, C_h, [src, 32] - ldp D_l, D_h, [src, 48] - ldp E_l, E_h, [srcend, -32] - ldp F_l, F_h, [srcend, -16] - stp A_l, A_h, [dstin] - stp B_l, B_h, [dstin, 16] - stp C_l, C_h, [dstin, 32] - stp D_l, D_h, [dstin, 48] - stp E_l, E_h, [dstend, -32] - stp F_l, F_h, [dstend, -16] - ret - - /* Align DST to 16 byte alignment so that we don't cross cache line - boundaries on both loads and stores. There are at least 96 bytes - to copy, so copy 16 bytes unaligned and then align. The loop - copies 64 bytes per iteration and prefetches one iteration ahead. */ - - .p2align 4 -L(copy_long): - and tmp1, dstin, 15 - bic dst, dstin, 15 - ldp D_l, D_h, [src] - sub src, src, tmp1 - add count, count, tmp1 /* Count is now 16 too large. */ - ldp A_l, A_h, [src, 16] - stp D_l, D_h, [dstin] - ldp B_l, B_h, [src, 32] - ldp C_l, C_h, [src, 48] - ldp D_l, D_h, [src, 64]! - subs count, count, 128 + 16 /* Test and readjust count. */ - b.ls L(last64) -L(loop64): - stp A_l, A_h, [dst, 16] - ldp A_l, A_h, [src, 16] - stp B_l, B_h, [dst, 32] - ldp B_l, B_h, [src, 32] - stp C_l, C_h, [dst, 48] - ldp C_l, C_h, [src, 48] - stp D_l, D_h, [dst, 64]! - ldp D_l, D_h, [src, 64]! - subs count, count, 64 - b.hi L(loop64) - - /* Write the last full set of 64 bytes. The remainder is at most 64 - bytes, so it is safe to always copy 64 bytes from the end even if - there is just 1 byte left. */ -L(last64): - ldp E_l, E_h, [srcend, -64] - stp A_l, A_h, [dst, 16] - ldp A_l, A_h, [srcend, -48] - stp B_l, B_h, [dst, 32] - ldp B_l, B_h, [srcend, -32] - stp C_l, C_h, [dst, 48] - ldp C_l, C_h, [srcend, -16] - stp D_l, D_h, [dst, 64] - stp E_l, E_h, [dstend, -64] - stp A_l, A_h, [dstend, -48] - stp B_l, B_h, [dstend, -32] - stp C_l, C_h, [dstend, -16] - ret - - .p2align 4 -L(move_long): - cbz tmp1, 3f - - add srcend, src, count - add dstend, dstin, count - - /* Align dstend to 16 byte alignment so that we don't cross cache line - boundaries on both loads and stores. There are at least 96 bytes - to copy, so copy 16 bytes unaligned and then align. The loop - copies 64 bytes per iteration and prefetches one iteration ahead. */ - - and tmp1, dstend, 15 - ldp D_l, D_h, [srcend, -16] - sub srcend, srcend, tmp1 - sub count, count, tmp1 - ldp A_l, A_h, [srcend, -16] - stp D_l, D_h, [dstend, -16] - ldp B_l, B_h, [srcend, -32] - ldp C_l, C_h, [srcend, -48] - ldp D_l, D_h, [srcend, -64]! - sub dstend, dstend, tmp1 - subs count, count, 128 - b.ls 2f - - nop -1: - stp A_l, A_h, [dstend, -16] - ldp A_l, A_h, [srcend, -16] - stp B_l, B_h, [dstend, -32] - ldp B_l, B_h, [srcend, -32] - stp C_l, C_h, [dstend, -48] - ldp C_l, C_h, [srcend, -48] - stp D_l, D_h, [dstend, -64]! - ldp D_l, D_h, [srcend, -64]! - subs count, count, 64 - b.hi 1b - - /* Write the last full set of 64 bytes. The remainder is at most 64 - bytes, so it is safe to always copy 64 bytes from the start even if - there is just 1 byte left. */ -2: - ldp G_l, G_h, [src, 48] - stp A_l, A_h, [dstend, -16] - ldp A_l, A_h, [src, 32] - stp B_l, B_h, [dstend, -32] - ldp B_l, B_h, [src, 16] - stp C_l, C_h, [dstend, -48] - ldp C_l, C_h, [src] - stp D_l, D_h, [dstend, -64] - stp G_l, G_h, [dstin, 48] - stp A_l, A_h, [dstin, 32] - stp B_l, B_h, [dstin, 16] - stp C_l, C_h, [dstin] -3: ret - -END (MEMCPY) -libc_hidden_builtin_def (MEMCPY) |