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authorRichard Qin <richard.qin.x@gmail.com>2026-07-10 11:31:46 +0800
committerRichard Qin <richard.qin.x@gmail.com>2026-07-10 11:31:46 +0800
commite90b72ec3082588b296956730bd2930cf8d5d671 (patch)
tree36ff6916af9b4176ea5a9662219d11e721f0b691 /na/lib/string/memset.c
parent1767d390fbf3d0c65389de46caf0b6d43ef3b6ad (diff)
downloadlume-e90b72ec3082588b296956730bd2930cf8d5d671.tar.gz
lume-e90b72ec3082588b296956730bd2930cf8d5d671.tar.xz
refactor: promote new architecture to repository root
Archive the deprecated implementation under lume-legacy, make the new kernel the default root-level build, and update repository entry points without changing kernel behavior.
Diffstat (limited to 'na/lib/string/memset.c')
-rw-r--r--na/lib/string/memset.c93
1 files changed, 0 insertions, 93 deletions
diff --git a/na/lib/string/memset.c b/na/lib/string/memset.c
deleted file mode 100644
index e780c71..0000000
--- a/na/lib/string/memset.c
+++ /dev/null
@@ -1,93 +0,0 @@
-/* SPDX-License-Identifier: MIT */
-/* Derived from musl libc (Copyright © 2005-2020 Rich Felker, et al.) */
-
-#include <string.h>
-#include <stdint.h>
-
-void *memset(void *dest, int c, size_t n)
-{
- unsigned char *s = dest;
- size_t k;
-
- /* Fill head and tail with minimal branching. Each
- * conditional ensures that all the subsequently used
- * offsets are well-defined and in the dest region. */
-
- if (!n) return dest;
- s[0] = c;
- s[n-1] = c;
- if (n <= 2) return dest;
- s[1] = c;
- s[2] = c;
- s[n-2] = c;
- s[n-3] = c;
- if (n <= 6) return dest;
- s[3] = c;
- s[n-4] = c;
- if (n <= 8) return dest;
-
- /* Advance pointer to align it at a 4-byte boundary,
- * and truncate n to a multiple of 4. The previous code
- * already took care of any head/tail that get cut off
- * by the alignment. */
-
- k = -(uintptr_t)s & 3;
- s += k;
- n -= k;
- n &= -4;
-
-#ifdef __GNUC__
- typedef uint32_t __attribute__((__may_alias__)) u32;
- typedef uint64_t __attribute__((__may_alias__)) u64;
-
- u32 c32 = ((u32)-1)/255 * (unsigned char)c;
-
- /* In preparation to copy 32 bytes at a time, aligned on
- * an 8-byte bounary, fill head/tail up to 28 bytes each.
- * As in the initial byte-based head/tail fill, each
- * conditional below ensures that the subsequent offsets
- * are valid (e.g. !(n<=24) implies n>=28). */
-
- *(u32 *)(s+0) = c32;
- *(u32 *)(s+n-4) = c32;
- if (n <= 8) return dest;
- *(u32 *)(s+4) = c32;
- *(u32 *)(s+8) = c32;
- *(u32 *)(s+n-12) = c32;
- *(u32 *)(s+n-8) = c32;
- if (n <= 24) return dest;
- *(u32 *)(s+12) = c32;
- *(u32 *)(s+16) = c32;
- *(u32 *)(s+20) = c32;
- *(u32 *)(s+24) = c32;
- *(u32 *)(s+n-28) = c32;
- *(u32 *)(s+n-24) = c32;
- *(u32 *)(s+n-20) = c32;
- *(u32 *)(s+n-16) = c32;
-
- /* Align to a multiple of 8 so we can fill 64 bits at a time,
- * and avoid writing the same bytes twice as much as is
- * practical without introducing additional branching. */
-
- k = 24 + ((uintptr_t)s & 4);
- s += k;
- n -= k;
-
- /* If this loop is reached, 28 tail bytes have already been
- * filled, so any remainder when n drops below 32 can be
- * safely ignored. */
-
- u64 c64 = c32 | ((u64)c32 << 32);
- for (; n >= 32; n-=32, s+=32) {
- *(u64 *)(s+0) = c64;
- *(u64 *)(s+8) = c64;
- *(u64 *)(s+16) = c64;
- *(u64 *)(s+24) = c64;
- }
-#else
- /* Pure C fallback with no aliasing violations. */
- for (; n; n--, s++) *s = c;
-#endif
-
- return dest;
-}