upstream/1.1.0_cvsrelease/1.1.0_cvs

1 files changed, 86 insertions, 0 deletions

diff --git a/lib/libc/i386/string/bcopy.S b/lib/libc/i386/string/bcopy.S
new file mode 100644
index 000000000000..b68cdf3c4805
--- /dev/null
+++ b/lib/libc/i386/string/bcopy.S
@@ -0,0 +1,86 @@
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	$Id: bcopy.S,v 1.1 1993/12/05 13:01:41 ats Exp $
+ */
+
+#if defined(LIBC_RCS) && !defined(lint)
+	.asciz "$Id: bcopy.S,v 1.1 1993/12/05 13:01:41 ats Exp $"
+#endif /* LIBC_RCS and not lint */
+
+#include "DEFS.h"
+
+	/*
+	 * (ov)bcopy (src,dst,cnt)
+	 *  ws@tools.de     (Wolfgang Solfrank, TooLs GmbH) +49-228-985800
+	 */
+
+ENTRY(bcopy)
+	pushl	%esi
+	pushl	%edi
+	movl	12(%esp),%esi
+	movl	16(%esp),%edi
+	movl	20(%esp),%ecx
+	cmpl	%esi,%edi	/* potentially overlapping? */
+	jnb	1f
+	cld			/* nope, copy forwards. */
+	shrl	$2,%ecx		/* copy by words */
+	rep
+	movsl
+	movl	20(%esp),%ecx
+	andl	$3,%ecx		/* any bytes left? */
+	rep
+	movsb
+	popl	%edi
+	popl	%esi
+	ret
+1:
+	addl	%ecx,%edi	/* copy backwards. */
+	addl	%ecx,%esi
+	std
+	andl	$3,%ecx		/* any fractional bytes? */
+	decl	%edi
+	decl	%esi
+	rep
+	movsb
+	movl	20(%esp),%ecx	/* copy remainder by words */
+	shrl	$2,%ecx
+	subl	$3,%esi
+	subl	$3,%edi
+	rep
+	movsl
+	popl	%edi
+	popl	%esi
+	cld
+	ret