merge x86_64 optimized string support

1 files changed, 41 insertions, 0 deletions

diff --git a/libc/string/x86_64/strcmp.S b/libc/string/x86_64/strcmp.S
new file mode 100644
index 000000000..0b401a773
--- /dev/null
+++ b/libc/string/x86_64/strcmp.S
@@ -0,0 +1,41 @@
+/* Highly optimized version for x86-64.
+   Copyright (C) 1999, 2000, 2002, 2003, 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Based on i686 version contributed by Ulrich Drepper
+   <drepper@cygnus.com>, 1999.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "_glibc_inc.h"
+
+        .text
+ENTRY (BP_SYM (strcmp))
+L(oop):	movb	(%rdi), %al
+	cmpb	(%rsi), %al
+	jne	L(neq)
+	incq	%rdi
+	incq	%rsi
+	testb	%al, %al
+	jnz	L(oop)
+
+	xorl	%eax, %eax
+	ret
+
+L(neq):	movl	$1, %eax
+	movl	$-1, %ecx
+	cmovbl	%ecx, %eax
+	ret
+END (BP_SYM (strcmp))