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Diffstat (limited to 'newlib/libc/machine/aarch64/memset.S')
| -rw-r--r-- | newlib/libc/machine/aarch64/memset.S | 246 |
1 files changed, 0 insertions, 246 deletions
diff --git a/newlib/libc/machine/aarch64/memset.S b/newlib/libc/machine/aarch64/memset.S deleted file mode 100644 index 20372df94..000000000 --- a/newlib/libc/machine/aarch64/memset.S +++ /dev/null @@ -1,246 +0,0 @@ -/* Copyright (c) 2012-2013, Linaro Limited - All rights reserved. - - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions are met: - * Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - * Redistributions in binary form must reproduce the above copyright - notice, this list of conditions and the following disclaimer in the - documentation and/or other materials provided with the distribution. - * Neither the name of the Linaro nor the - names of its contributors may be used to endorse or promote products - derived from this software without specific prior written permission. - - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ - -/* Assumptions: - * - * ARMv8-a, AArch64 - * Unaligned accesses - * - */ - -#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED)) -/* See memset-stub.c */ -#else - -/* By default we assume that the DC instruction can be used to zero - data blocks more efficiently. In some circumstances this might be - unsafe, for example in an asymmetric multiprocessor environment with - different DC clear lengths (neither the upper nor lower lengths are - safe to use). The feature can be disabled by defining DONT_USE_DC. - - If code may be run in a virtualized environment, then define - MAYBE_VIRT. This will cause the code to cache the system register - values rather than re-reading them each call. */ - -#define dstin x0 -#define val w1 -#define count x2 -#define tmp1 x3 -#define tmp1w w3 -#define tmp2 x4 -#define tmp2w w4 -#define zva_len_x x5 -#define zva_len w5 -#define zva_bits_x x6 - -#define A_l x7 -#define A_lw w7 -#define dst x8 -#define tmp3w w9 - - - .macro def_fn f p2align=0 - .text - .p2align \p2align - .global \f - .type \f, %function -\f: - .endm - -def_fn memset p2align=6 - - mov dst, dstin /* Preserve return value. */ - ands A_lw, val, #255 -#ifndef DONT_USE_DC - b.eq .Lzero_mem -#endif - orr A_lw, A_lw, A_lw, lsl #8 - orr A_lw, A_lw, A_lw, lsl #16 - orr A_l, A_l, A_l, lsl #32 -.Ltail_maybe_long: - cmp count, #64 - b.ge .Lnot_short -.Ltail_maybe_tiny: - cmp count, #15 - b.le .Ltail15tiny -.Ltail63: - ands tmp1, count, #0x30 - b.eq .Ltail15 - add dst, dst, tmp1 - cmp tmp1w, #0x20 - b.eq 1f - b.lt 2f - stp A_l, A_l, [dst, #-48] -1: - stp A_l, A_l, [dst, #-32] -2: - stp A_l, A_l, [dst, #-16] - -.Ltail15: - and count, count, #15 - add dst, dst, count - stp A_l, A_l, [dst, #-16] /* Repeat some/all of last store. */ - ret - -.Ltail15tiny: - /* Set up to 15 bytes. Does not assume earlier memory - being set. */ - tbz count, #3, 1f - str A_l, [dst], #8 -1: - tbz count, #2, 1f - str A_lw, [dst], #4 -1: - tbz count, #1, 1f - strh A_lw, [dst], #2 -1: - tbz count, #0, 1f - strb A_lw, [dst] -1: - ret - - /* Critical loop. Start at a new cache line boundary. Assuming - * 64 bytes per line, this ensures the entire loop is in one line. */ - .p2align 6 -.Lnot_short: - neg tmp2, dst - ands tmp2, tmp2, #15 - b.eq 2f - /* Bring DST to 128-bit (16-byte) alignment. We know that there's - * more than that to set, so we simply store 16 bytes and advance by - * the amount required to reach alignment. */ - sub count, count, tmp2 - stp A_l, A_l, [dst] - add dst, dst, tmp2 - /* There may be less than 63 bytes to go now. */ - cmp count, #63 - b.le .Ltail63 -2: - sub dst, dst, #16 /* Pre-bias. */ - sub count, count, #64 -1: - stp A_l, A_l, [dst, #16] - stp A_l, A_l, [dst, #32] - stp A_l, A_l, [dst, #48] - stp A_l, A_l, [dst, #64]! - subs count, count, #64 - b.ge 1b - tst count, #0x3f - add dst, dst, #16 - b.ne .Ltail63 - ret - -#ifndef DONT_USE_DC - /* For zeroing memory, check to see if we can use the ZVA feature to - * zero entire 'cache' lines. */ -.Lzero_mem: - mov A_l, #0 - cmp count, #63 - b.le .Ltail_maybe_tiny - neg tmp2, dst - ands tmp2, tmp2, #15 - b.eq 1f - sub count, count, tmp2 - stp A_l, A_l, [dst] - add dst, dst, tmp2 - cmp count, #63 - b.le .Ltail63 -1: - /* For zeroing small amounts of memory, it's not worth setting up - * the line-clear code. */ - cmp count, #128 - b.lt .Lnot_short -#ifdef MAYBE_VIRT - /* For efficiency when virtualized, we cache the ZVA capability. */ - adrp tmp2, .Lcache_clear - ldr zva_len, [tmp2, #:lo12:.Lcache_clear] - tbnz zva_len, #31, .Lnot_short - cbnz zva_len, .Lzero_by_line - mrs tmp1, dczid_el0 - tbz tmp1, #4, 1f - /* ZVA not available. Remember this for next time. */ - mov zva_len, #~0 - str zva_len, [tmp2, #:lo12:.Lcache_clear] - b .Lnot_short -1: - mov tmp3w, #4 - and zva_len, tmp1w, #15 /* Safety: other bits reserved. */ - lsl zva_len, tmp3w, zva_len - str zva_len, [tmp2, #:lo12:.Lcache_clear] -#else - mrs tmp1, dczid_el0 - tbnz tmp1, #4, .Lnot_short - mov tmp3w, #4 - and zva_len, tmp1w, #15 /* Safety: other bits reserved. */ - lsl zva_len, tmp3w, zva_len -#endif - -.Lzero_by_line: - /* Compute how far we need to go to become suitably aligned. We're - * already at quad-word alignment. */ - cmp count, zva_len_x - b.lt .Lnot_short /* Not enough to reach alignment. */ - sub zva_bits_x, zva_len_x, #1 - neg tmp2, dst - ands tmp2, tmp2, zva_bits_x - b.eq 1f /* Already aligned. */ - /* Not aligned, check that there's enough to copy after alignment. */ - sub tmp1, count, tmp2 - cmp tmp1, #64 - ccmp tmp1, zva_len_x, #8, ge /* NZCV=0b1000 */ - b.lt .Lnot_short - /* We know that there's at least 64 bytes to zero and that it's safe - * to overrun by 64 bytes. */ - mov count, tmp1 -2: - stp A_l, A_l, [dst] - stp A_l, A_l, [dst, #16] - stp A_l, A_l, [dst, #32] - subs tmp2, tmp2, #64 - stp A_l, A_l, [dst, #48] - add dst, dst, #64 - b.ge 2b - /* We've overrun a bit, so adjust dst downwards. */ - add dst, dst, tmp2 -1: - sub count, count, zva_len_x -3: - dc zva, dst - add dst, dst, zva_len_x - subs count, count, zva_len_x - b.ge 3b - ands count, count, zva_bits_x - b.ne .Ltail_maybe_long - ret - .size memset, .-memset -#ifdef MAYBE_VIRT - .bss - .p2align 2 -.Lcache_clear: - .space 4 -#endif -#endif /* DONT_USE_DC */ -#endif |