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>

2 files changed, 22 insertions, 1 deletions

diff --git a/arch/cris/arch-v32/lib/Makefile b/arch/cris/arch-v32/lib/Makefile
index eb4aad1f1158..dd296b9db034 100644
--- a/arch/cris/arch-v32/lib/Makefile
+++ b/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
 
diff --git a/arch/cris/arch-v32/lib/strcmp.S b/arch/cris/arch-v32/lib/strcmp.S
new file mode 100644
index 000000000000..8f7a1ee62591
--- /dev/null
+++ b/arch/cris/arch-v32/lib/strcmp.S
@@ -0,0 +1,21 @@
+; 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