CRISv32: Add arch optimized strcmp.

Add an optimized strcmp for CRISv32. This improves strcmp performance
with about 25% when comparing a 55 character string with itself.
Signed-off-by: Edgar Iglesias <edgar@axis.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>

arch/cris/arch-v32/lib/Makefile

@@ -3,5 +3,5 @@
 #
 
 lib-y  = checksum.o checksumcopy.o string.o usercopy.o memset.o \
-	csumcpfruser.o spinlock.o delay.o
+	csumcpfruser.o spinlock.o delay.o strcmp.o
 

arch/cris/arch-v32/lib/strcmp.S

+; strcmp.S -- CRISv32 version.
+; Copyright (C) 2008 AXIS Communications AB
+; Written by Edgar E. Iglesias
+;
+; This source code is licensed under the GNU General Public License,
+; Version 2.  See the file COPYING for more details.
+
+	.global	strcmp
+	.type	strcmp,@function
+strcmp:
+1:
+	move.b	[$r10+], $r12
+	seq	$r13
+	sub.b	[$r11+], $r12
+	or.b	$r12, $r13
+	beq	1b
+	nop
+
+	ret
+	movs.b	$r12, $r10
+	.size	strcmp, . - strcmp

arch/cris/include/asm/string.h

@@ -11,4 +11,10 @@ extern void *memcpy(void *, const void *, size_t);
 #define __HAVE_ARCH_MEMSET
 extern void *memset(void *, int, size_t);
 
+#ifdef CONFIG_ETRAX_ARCH_V32
+/* For v32 we provide strcmp.  */
+#define __HAVE_ARCH_STRCMP
+extern int strcmp(const char *s1, const char *s2);
+#endif
+
 #endif