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-rw-r--r--sysdeps/i386/i586/memcopy.h94
1 files changed, 94 insertions, 0 deletions
diff --git a/sysdeps/i386/i586/memcopy.h b/sysdeps/i386/i586/memcopy.h
new file mode 100644
index 0000000000..a9bb9e7a40
--- /dev/null
+++ b/sysdeps/i386/i586/memcopy.h
@@ -0,0 +1,94 @@
+/* memcopy.h -- definitions for memory copy functions.  Pentium version.
+   Copyright (C) 1994 Free Software Foundation, Inc.
+   Contributed by Torbjorn Granlund (tege@sics.se).
+
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/* Get the i386 definitions.  We will override some of them below.  */
+#include_next <memcopy.h>
+
+
+/* Written like this, the Pentium pipeline can execute the loop at a
+   sustained rate of 2 instructions/clock, or asymptotically 480
+   Mbytes/second at 60Mhz.  */
+
+#undef	WORD_COPY_FWD
+#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes)		\
+  do									\
+    {									\
+      asm volatile ("subl	$32,%2\n"				\
+		    "js		2f\n"					\
+		    "1:\n"						\
+		    "movl	0(%1),%%eax\n"				\
+		    "movl	4(%1),%%edx\n"				\
+		    "movl	%%eax,0(%0)\n"				\
+		    "movl	%%edx,4(%0)\n"				\
+		    "movl	8(%1),%%eax\n"				\
+		    "movl	12(%1),%%edx\n"				\
+		    "movl	%%eax,8(%0)\n"				\
+		    "movl	%%edx,12(%0)\n"				\
+		    "movl	16(%1),%%eax\n"				\
+		    "movl	20(%1),%%edx\n"				\
+		    "movl	%%eax,16(%0)\n"				\
+		    "movl	%%edx,20(%0)\n"				\
+		    "movl	24(%1),%%eax\n"				\
+		    "movl	28(%1),%%edx\n"				\
+		    "movl	%%eax,24(%0)\n"				\
+		    "movl	%%edx,28(%0)\n"				\
+		    "addl	$32,%1\n"				\
+		    "addl	$32,%0\n"				\
+		    "subl	$32,%2\n"				\
+		    "jns	1b\n"					\
+		    "2: addl	$32,%2" :				\
+		    "=r" (dst_bp), "=r" (src_bp), "=r" (nbytes_left) :	\
+		    "0" (dst_bp), "1" (src_bp), "2" (nbytes) :		\
+		    "ax", "dx");					\
+    } while (0)
+
+#undef	WORD_COPY_BWD
+#define WORD_COPY_BWD(dst_ep, src_ep, nbytes_left, nbytes)		\
+  do									\
+    {									\
+      asm volatile ("subl	$32,%2\n"				\
+		    "js		2f\n"					\
+		    "1:\n"						\
+		    "movl	-4(%1),%%eax\n"				\
+		    "movl	-8(%1),%%edx\n"				\
+		    "movl	%%eax,-4(%0)\n"				\
+		    "movl	%%edx,-8(%0)\n"				\
+		    "movl	-12(%1),%%eax\n"			\
+		    "movl	-16(%1),%%edx\n"			\
+		    "movl	%%eax,-12(%0)\n"			\
+		    "movl	%%edx,-16(%0)\n"			\
+		    "movl	-20(%1),%%eax\n"			\
+		    "movl	-24(%1),%%edx\n"			\
+		    "movl	%%eax,-20(%0)\n"			\
+		    "movl	%%edx,-24(%0)\n"			\
+		    "movl	-28(%1),%%eax\n"			\
+		    "movl	-32(%1),%%edx\n"			\
+		    "movl	%%eax,-28(%0)\n"			\
+		    "movl	%%edx,-32(%0)\n"			\
+		    "subl	$32,%1\n"				\
+		    "subl	$32,%0\n"				\
+		    "subl	$32,%2\n"				\
+		    "jns	1b\n"					\
+		    "2: addl	$32,%2" :				\
+		    "=r" (dst_bp), "=r" (src_bp), "=r" (nbytes_left) :	\
+		    "0" (dst_bp), "1" (src_bp), "2" (nbytes) :		\
+		    "ax", "dx");					\
+    } while (0)