Use memcpy in memmove when possible

4 files changed, 36 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 96328a0548..0f09cd06c5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2012-11-06  Maxim Kuvyrkov  <maxim@codesourcery.com>
+
+	* string/memmove.c: Use memcpy when possible.
+
 2012-11-06  Andreas Jaeger  <aj@suse.de>
 
 	* po/eo.po: Update from translation team.
diff --git a/ports/ChangeLog.mips b/ports/ChangeLog.mips
index 8dc4893b03..cdf4ea3c54 100644
--- a/ports/ChangeLog.mips
+++ b/ports/ChangeLog.mips
@@ -1,3 +1,7 @@
+2012-11-06  Maxim Kuvyrkov  <maxim@codesourcery.com>
+
+        * sysdeps/mips/memmove.c: New file.  Use memcpy for forward memmove.
+
 2012-11-05  Joseph Myers  <joseph@codesourcery.com>
 
 	* sysdeps/unix/sysv/linux/mips/nptl/lowlevellock.h
diff --git a/ports/sysdeps/mips/memmove.c b/ports/sysdeps/mips/memmove.c
new file mode 100644
index 0000000000..1426ec32eb
--- /dev/null
+++ b/ports/sysdeps/mips/memmove.c
@@ -0,0 +1,23 @@
+/* Copy memory to memory until the specified number of bytes
+   has been copied.  Overlap is handled correctly.
+   Copyright (C) 2012 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Maxim Kuvyrkov <maxim@codesourcery.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+/* MIPS' implementation of memcpy is safe to use for memmove.  */
+#define MEMCPY_OK_FOR_FWD_MEMMOVE 1
+#include <string/memmove.c>
diff --git a/string/memmove.c b/string/memmove.c
index ede27ffcf2..bf7dcc1627 100644
--- a/string/memmove.c
+++ b/string/memmove.c
@@ -1,6 +1,6 @@
 /* Copy memory to memory until the specified number of bytes
    has been copied.  Overlap is handled correctly.
-   Copyright (C) 1991, 1995, 1996, 1997, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1991-2012 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Torbjorn Granlund (tege@sics.se).
 
@@ -55,6 +55,9 @@ MEMMOVE (a1, a2, len)
     {
       /* Copy from the beginning to the end.  */
 
+#if MEMCPY_OK_FOR_FWD_MEMMOVE
+      dest = memcpy (dest, src, len);
+#else
       /* If there not too few bytes to copy, use word copy.  */
       if (len >= OP_T_THRES)
 	{
@@ -79,6 +82,7 @@ MEMMOVE (a1, a2, len)
 
       /* There are just a few bytes to copy.  Use byte memory operations.  */
       BYTE_COPY_FWD (dstp, srcp, len);
+#endif /* MEMCPY_OK_FOR_FWD_MEMMOVE */
     }
   else
     {