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Diffstat (limited to 'sysdeps/aarch64/multiarch/memcpy_advsimd.S')
| -rw-r--r-- | sysdeps/aarch64/multiarch/memcpy_advsimd.S | 248 |
1 files changed, 0 insertions, 248 deletions
diff --git a/sysdeps/aarch64/multiarch/memcpy_advsimd.S b/sysdeps/aarch64/multiarch/memcpy_advsimd.S deleted file mode 100644 index 48bb6d7ca4..0000000000 --- a/sysdeps/aarch64/multiarch/memcpy_advsimd.S +++ /dev/null @@ -1,248 +0,0 @@ -/* Generic optimized memcpy using SIMD. - Copyright (C) 2020 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> - -/* Assumptions: - * - * ARMv8-a, AArch64, Advanced SIMD, 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 B_l x8 -#define B_lw w8 -#define B_h x9 -#define C_lw w10 -#define tmp1 x14 - -#define A_q q0 -#define B_q q1 -#define C_q q2 -#define D_q q3 -#define E_q q4 -#define F_q q5 -#define G_q q6 -#define H_q q7 - - -/* This implementation supports both memcpy and memmove and shares most code. - It uses unaligned accesses and branchless sequences to keep the code small, - simple and improve performance. - - Copies are split into 3 main cases: small copies of up to 32 bytes, medium - copies of up to 128 bytes, and large copies. The overhead of the overlap - check in memmove is negligible since it is only required for large copies. - - Large copies use a software pipelined loop processing 64 bytes per - iteration. The destination pointer is 16-byte aligned to minimize - unaligned accesses. The loop tail is handled by always copying 64 bytes - from the end. */ - -ENTRY (__memcpy_simd) - DELOUSE (0) - DELOUSE (1) - DELOUSE (2) - - add srcend, src, count - add dstend, dstin, count - cmp count, 128 - b.hi L(copy_long) - cmp count, 32 - b.hi L(copy32_128) - - /* Small copies: 0..32 bytes. */ - cmp count, 16 - b.lo L(copy16) - ldr A_q, [src] - ldr B_q, [srcend, -16] - str A_q, [dstin] - str B_q, [dstend, -16] - ret - - /* Copy 8-15 bytes. */ -L(copy16): - tbz count, 3, L(copy8) - ldr A_l, [src] - ldr A_h, [srcend, -8] - str A_l, [dstin] - str A_h, [dstend, -8] - ret - - /* Copy 4-7 bytes. */ -L(copy8): - tbz count, 2, L(copy4) - ldr A_lw, [src] - ldr B_lw, [srcend, -4] - str A_lw, [dstin] - str B_lw, [dstend, -4] - ret - - /* Copy 0..3 bytes using a branchless sequence. */ -L(copy4): - cbz count, L(copy0) - lsr tmp1, count, 1 - ldrb A_lw, [src] - ldrb C_lw, [srcend, -1] - ldrb B_lw, [src, tmp1] - strb A_lw, [dstin] - strb B_lw, [dstin, tmp1] - strb C_lw, [dstend, -1] -L(copy0): - ret - - .p2align 4 - /* Medium copies: 33..128 bytes. */ -L(copy32_128): - ldp A_q, B_q, [src] - ldp C_q, D_q, [srcend, -32] - cmp count, 64 - b.hi L(copy128) - stp A_q, B_q, [dstin] - stp C_q, D_q, [dstend, -32] - ret - - .p2align 4 - /* Copy 65..128 bytes. */ -L(copy128): - ldp E_q, F_q, [src, 32] - cmp count, 96 - b.ls L(copy96) - ldp G_q, H_q, [srcend, -64] - stp G_q, H_q, [dstend, -64] -L(copy96): - stp A_q, B_q, [dstin] - stp E_q, F_q, [dstin, 32] - stp C_q, D_q, [dstend, -32] - ret - - /* Align loop64 below to 16 bytes. */ - nop - - /* Copy more than 128 bytes. */ -L(copy_long): - /* Copy 16 bytes and then align src to 16-byte alignment. */ - ldr D_q, [src] - and tmp1, src, 15 - bic src, src, 15 - sub dst, dstin, tmp1 - add count, count, tmp1 /* Count is now 16 too large. */ - ldp A_q, B_q, [src, 16] - str D_q, [dstin] - ldp C_q, D_q, [src, 48] - subs count, count, 128 + 16 /* Test and readjust count. */ - b.ls L(copy64_from_end) -L(loop64): - stp A_q, B_q, [dst, 16] - ldp A_q, B_q, [src, 80] - stp C_q, D_q, [dst, 48] - ldp C_q, D_q, [src, 112] - add src, src, 64 - add dst, dst, 64 - subs count, count, 64 - b.hi L(loop64) - - /* Write the last iteration and copy 64 bytes from the end. */ -L(copy64_from_end): - ldp E_q, F_q, [srcend, -64] - stp A_q, B_q, [dst, 16] - ldp A_q, B_q, [srcend, -32] - stp C_q, D_q, [dst, 48] - stp E_q, F_q, [dstend, -64] - stp A_q, B_q, [dstend, -32] - ret - -END (__memcpy_simd) -libc_hidden_builtin_def (__memcpy_simd) - - -ENTRY (__memmove_simd) - DELOUSE (0) - DELOUSE (1) - DELOUSE (2) - - add srcend, src, count - add dstend, dstin, count - cmp count, 128 - b.hi L(move_long) - cmp count, 32 - b.hi L(copy32_128) - - /* Small moves: 0..32 bytes. */ - cmp count, 16 - b.lo L(copy16) - ldr A_q, [src] - ldr B_q, [srcend, -16] - str A_q, [dstin] - str B_q, [dstend, -16] - ret - -L(move_long): - /* Only use backward copy if there is an overlap. */ - sub tmp1, dstin, src - cbz tmp1, L(move0) - cmp tmp1, count - b.hs L(copy_long) - - /* Large backwards copy for overlapping copies. - Copy 16 bytes and then align srcend to 16-byte alignment. */ -L(copy_long_backwards): - ldr D_q, [srcend, -16] - and tmp1, srcend, 15 - bic srcend, srcend, 15 - sub count, count, tmp1 - ldp A_q, B_q, [srcend, -32] - str D_q, [dstend, -16] - ldp C_q, D_q, [srcend, -64] - sub dstend, dstend, tmp1 - subs count, count, 128 - b.ls L(copy64_from_start) - -L(loop64_backwards): - str B_q, [dstend, -16] - str A_q, [dstend, -32] - ldp A_q, B_q, [srcend, -96] - str D_q, [dstend, -48] - str C_q, [dstend, -64]! - ldp C_q, D_q, [srcend, -128] - sub srcend, srcend, 64 - subs count, count, 64 - b.hi L(loop64_backwards) - - /* Write the last iteration and copy 64 bytes from the start. */ -L(copy64_from_start): - ldp E_q, F_q, [src, 32] - stp A_q, B_q, [dstend, -32] - ldp A_q, B_q, [src] - stp C_q, D_q, [dstend, -64] - stp E_q, F_q, [dstin, 32] - stp A_q, B_q, [dstin] -L(move0): - ret - -END (__memmove_simd) -libc_hidden_builtin_def (__memmove_simd) |