X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fstring%2Fmemmove.c;h=f225bb30b84be684ef7798f55680bc9b596124b1;hb=8cd738bbee3b4e60a99b71599c338bf444070f18;hp=22bb4b3559d3e76a8f064028925352f78a735ab8;hpb=0b44a0315b47dd8eced9f3b7f31580cf14bbfc01;p=musl

diff --git a/src/string/memmove.c b/src/string/memmove.c
index 22bb4b35..f225bb30 100644
--- a/src/string/memmove.c
+++ b/src/string/memmove.c
@@ -1,14 +1,36 @@
 #include <string.h>
+#include <stdint.h>
+
+#define WT size_t
+#define WS (sizeof(WT))
 
 void *memmove(void *dest, const void *src, size_t n)
 {
 	char *d = dest;
 	const char *s = src;
+
 	if (d==s) return d;
-	if ((size_t)(d-s) < n) {
-		while (n--) d[n] = s[n];
-		return dest;
+	if ((uintptr_t)s-(uintptr_t)d-n <= -2*n) return memcpy(d, s, n);
+
+	if (d<s) {
+		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;
+		}
+		for (; n; n--) *d++ = *s++;
+	} else {
+		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);
+		}
+		while (n) n--, d[n] = s[n];
 	}
-	/* Assumes memcpy is overlap-safe when dest < src */
-	return memcpy(d, s, n);
+
+	return dest;
 }