Make both stpcpy and strcpy be assembly language implementations

on amd64.

Submitted by:	Guillaume Morin (guillaume at morinfr.org)
Reviewed by:	kib, jhb
Approved by:	re (bz)
MFC after:	1 month

3 files changed, 60 insertions, 20 deletions

diff --git a/lib/libc/amd64/string/Makefile.inc b/lib/libc/amd64/string/Makefile.inc
index f5d69d6..46571ab 100644
--- a/lib/libc/amd64/string/Makefile.inc
+++ b/lib/libc/amd64/string/Makefile.inc
@@ -1,4 +1,4 @@
 # $FreeBSD$
 
 MDSRCS+= bcmp.S bcopy.S bzero.S memcmp.S memcpy.S memmove.S memset.S \
-	strcat.S strcmp.S strcpy.S
+	strcat.S strcmp.S stpcpy.S strcpy.c
diff --git a/lib/libc/amd64/string/strcpy.S b/lib/libc/amd64/string/stpcpy.S
index 5feb925..c8772f8 100644
--- a/lib/libc/amd64/string/strcpy.S
+++ b/lib/libc/amd64/string/stpcpy.S
@@ -1,17 +1,14 @@
 /*
- * Written by J.T. Conklin <jtc@acorntoolworks.com>
+ * Adapted by Guillaume Morin <guillaume@hudson-trading.com> from strcpy.S
+ * written by J.T. Conklin <jtc@acorntoolworks.com>
  * Public domain.
  */
 
 #include <machine/asm.h>
 __FBSDID("$FreeBSD$");
 
-#if 0
-	RCSID("$NetBSD: strcpy.S,v 1.3 2004/07/19 20:04:41 drochner Exp $")
-#endif
-
 /*
- * This strcpy implementation copies a byte at a time until the
+ * This stpcpy implementation copies a byte at a time until the
  * source pointer is aligned to a word boundary, it then copies by
  * words until it finds a word containing a zero byte, and finally
  * copies by bytes until the end of the string is reached.
@@ -23,10 +20,11 @@ __FBSDID("$FreeBSD$");
  * requirements.
  */
 
-ENTRY(strcpy)
-	movq	%rdi,%rax
-	movabsq	$0x0101010101010101,%r8
-	movabsq	$0x8080808080808080,%r9
+	.globl	stpcpy,__stpcpy
+ENTRY(stpcpy)
+__stpcpy:
+	movabsq $0x0101010101010101,%r8
+	movabsq $0x8080808080808080,%r9
 
 	/*
 	 * Align source to a word boundary.
@@ -41,6 +39,8 @@ ENTRY(strcpy)
 	incq	%rdi
 	testb	%dl,%dl
 	jne	.Lalign
+	movq	%rdi,%rax
+	dec	%rax
 	ret
 
 	.p2align 4
@@ -61,54 +61,56 @@ ENTRY(strcpy)
 	 */
 
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 1st byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 2nd byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 3rd byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 4th byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 5th byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 6th byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
-	incq	%rdi
 	testb	%dl,%dl		/* 7th byte == 0? */
 	je	.Ldone
+	incq	%rdi
 
 	shrq	$8,%rdx
 	movb	%dl,(%rdi)
 	incq	%rdi
 	testb	%dl,%dl		/* 8th byte == 0? */
 	jne	.Lword_aligned
+	decq	%rdi
 
 .Ldone:
+	movq	%rdi,%rax
 	ret
-END(strcpy)
-
+END(stpcpy)
+	
 	.section .note.GNU-stack,"",%progbits
diff --git a/lib/libc/amd64/string/strcpy.c b/lib/libc/amd64/string/strcpy.c
new file mode 100644
index 0000000..11a24eb
--- /dev/null
+++ b/lib/libc/amd64/string/strcpy.c
@@ -0,0 +1,38 @@
+/*
+ * Copyright 2011 George V. Neville-Neil. All rights reserved.
+ *
+ * The compilation of software known as FreeBSD is distributed under the
+ * following terms:
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+char *__stpcpy(char * __restrict, const char * __restrict);
+
+char *
+strcpy(char * __restrict to, const char * __restrict from)
+{
+	__stpcpy(to, from);
+	return(to);
+}