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-rw-r--r--libc/string/i386/memmove.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/libc/string/i386/memmove.c b/libc/string/i386/memmove.c
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+++ b/libc/string/i386/memmove.c
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+/*
+ * This string-include defines all string functions as inline
+ * functions. Use gcc. It also assumes ds=es=data space, this should be
+ * normal. Most of the string-functions are rather heavily hand-optimized,
+ * see especially strtok,strstr,str[c]spn. They should work, but are not
+ * very easy to understand. Everything is done entirely within the register
+ * set, making the functions fast and clean. String instructions have been
+ * used through-out, making for "slightly" unclear code :-)
+ *
+ * NO Copyright (C) 1991, 1992 Linus Torvalds,
+ * consider these trivial functions to be PD.
+ */
+
+/*
+ * Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
+ *
+ * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+ */
+
+/*
+ * Modified for uClibc by Erik Andersen <andersen@codepoet.org>
+ * These make no attempt to use nifty things like mmx/3dnow/etc.
+ * These are not inline, and will therefore not be as fast as
+ * modifying the headers to use inlines (and cannot therefore
+ * do tricky things when dealing with const memory). But they
+ * should (I hope!) be faster than their generic equivalents....
+ *
+ * More importantly, these should provide a good example for
+ * others to follow when adding arch specific optimizations.
+ * -Erik
+ */
+
+#define _GNU_SOURCE
+#include <string.h>
+
+void attribute_hidden *__memmove(void *dest, const void *src, size_t n)
+{
+ int d0, d1, d2;
+ if (dest<src)
+ __asm__ __volatile__(
+ "rep\n\t"
+ "movsb"
+ : "=&c" (d0), "=&S" (d1), "=&D" (d2)
+ :"0" (n),"1" (src),"2" (dest)
+ : "memory");
+ else
+ __asm__ __volatile__(
+ "std\n\t"
+ "rep\n\t"
+ "movsb\n\t"
+ "cld"
+ : "=&c" (d0), "=&S" (d1), "=&D" (d2)
+ :"0" (n),
+ "1" (n-1+(const char *)src),
+ "2" (n-1+(char *)dest)
+ :"memory");
+ return dest;
+}
+
+strong_alias(__memmove, memmove)