From 102b0d2daa97dae68d3eed54d8fe37a9cc38a892 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 11:13:47 +0200 Subject: Adding upstream version 2.8.0+dfsg. Signed-off-by: Daniel Baumann --- lib/libc/memset.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) create mode 100644 lib/libc/memset.c (limited to 'lib/libc/memset.c') diff --git a/lib/libc/memset.c b/lib/libc/memset.c new file mode 100644 index 0000000..17f798c --- /dev/null +++ b/lib/libc/memset.c @@ -0,0 +1,51 @@ +/* + * Copyright (c) 2013-2020, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include +#include +#include + +void *memset(void *dst, int val, size_t count) +{ + uint8_t *ptr = dst; + uint64_t *ptr64; + uint64_t fill = (unsigned char)val; + + /* Simplify code below by making sure we write at least one byte. */ + if (count == 0U) { + return dst; + } + + /* Handle the first part, until the pointer becomes 64-bit aligned. */ + while (((uintptr_t)ptr & 7U) != 0U) { + *ptr = (uint8_t)val; + ptr++; + if (--count == 0U) { + return dst; + } + } + + /* Duplicate the fill byte to the rest of the 64-bit word. */ + fill |= fill << 8; + fill |= fill << 16; + fill |= fill << 32; + + /* Use 64-bit writes for as long as possible. */ + ptr64 = (uint64_t *)ptr; + for (; count >= 8U; count -= 8) { + *ptr64 = fill; + ptr64++; + } + + /* Handle the remaining part byte-per-byte. */ + ptr = (uint8_t *)ptr64; + while (count-- > 0U) { + *ptr = (uint8_t)val; + ptr++; + } + + return dst; +} -- cgit v1.2.3