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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 13:54:38 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 13:54:38 +0000
commit8c1ab65c0f548d20b7f177bdb736daaf603340e1 (patch)
treedf55b7e75bf43f2bf500845b105afe3ac3a5157e /libc-top-half/musl/src/string/memmove.c
parentInitial commit. (diff)
downloadwasi-libc-8c1ab65c0f548d20b7f177bdb736daaf603340e1.tar.xz
wasi-libc-8c1ab65c0f548d20b7f177bdb736daaf603340e1.zip
Adding upstream version 0.0~git20221206.8b7148f.upstream/0.0_git20221206.8b7148f
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'libc-top-half/musl/src/string/memmove.c')
-rw-r--r--libc-top-half/musl/src/string/memmove.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/string/memmove.c b/libc-top-half/musl/src/string/memmove.c
new file mode 100644
index 0000000..7376a52
--- /dev/null
+++ b/libc-top-half/musl/src/string/memmove.c
@@ -0,0 +1,46 @@
+#include <string.h>
+#include <stdint.h>
+
+#ifdef __GNUC__
+typedef __attribute__((__may_alias__)) size_t WT;
+#define WS (sizeof(WT))
+#endif
+
+void *memmove(void *dest, const void *src, size_t n)
+{
+#if defined(__wasm_bulk_memory__)
+ if (n > BULK_MEMORY_THRESHOLD)
+ return __builtin_memmove(dest, src, n);
+#endif
+ char *d = dest;
+ const char *s = src;
+
+ if (d==s) return d;
+ if ((uintptr_t)s-(uintptr_t)d-n <= -2*n) return memcpy(d, s, n);
+
+ if (d<s) {
+#ifdef __GNUC__
+ if ((uintptr_t)s % WS == (uintptr_t)d % WS) {
+ while ((uintptr_t)d % WS) {
+ if (!n--) return dest;
+ *d++ = *s++;
+ }
+ for (; n>=WS; n-=WS, d+=WS, s+=WS) *(WT *)d = *(WT *)s;
+ }
+#endif
+ for (; n; n--) *d++ = *s++;
+ } else {
+#ifdef __GNUC__
+ if ((uintptr_t)s % WS == (uintptr_t)d % WS) {
+ while ((uintptr_t)(d+n) % WS) {
+ if (!n--) return dest;
+ d[n] = s[n];
+ }
+ while (n>=WS) n-=WS, *(WT *)(d+n) = *(WT *)(s+n);
+ }
+#endif
+ while (n) n--, d[n] = s[n];
+ }
+
+ return dest;
+}