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/* 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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#ifdef USE_MTAG
/* Use the same register names and assignments as memset. */
#include "memset-reg.h"
.arch armv8.5-a
.arch_extension memtag
/* NB, only supported on variants with 64-bit pointers. */
/* FIXME: This is a minimal implementation. We could do much better than
this for large values of COUNT. */
ENTRY(__libc_mtag_memset_with_tag)
and valw, valw, 255
orr valw, valw, valw, lsl 8
orr valw, valw, valw, lsl 16
orr val, val, val, lsl 32
mov dst, dstin
L(loop):
stgp val, val, [dst], #16
subs count, count, 16
bne L(loop)
#if 0
/* This is not currently needed, since for now we are only called
to tag memory that is taggable. */
ldg dstin, [dstin] // Recover the tag created (might be untagged).
#endif
ret
END (__libc_mtag_memset_with_tag)
#endif /* USE_MTAG */
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