[src/trunk]: src/common/lib/libc/arch/arm/string Fix case when searching for ...

[matt <matt%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/4775a2e794c2
branches:  trunk
changeset: 784034:4775a2e794c2
user:      matt <matt%NetBSD.org@localhost>
date:      Tue Jan 15 16:52:35 2013 +0000

description:
Fix case when searching for NUL.

diffstat:

 common/lib/libc/arch/arm/string/strchr_arm.S |  27 ++++++++++++++-------------
 1 files changed, 14 insertions(+), 13 deletions(-)

diffs (62 lines):

diff -r 28af58005cb4 -r 4775a2e794c2 common/lib/libc/arch/arm/string/strchr_arm.S
--- a/common/lib/libc/arch/arm/string/strchr_arm.S      Tue Jan 15 13:52:26 2013 +0000
+++ b/common/lib/libc/arch/arm/string/strchr_arm.S      Tue Jan 15 16:52:35 2013 +0000
@@ -29,7 +29,7 @@
 
 #include <machine/asm.h>
 
-RCSID("$NetBSD: strchr_arm.S,v 1.1 2013/01/15 02:04:04 matt Exp $")
+RCSID("$NetBSD: strchr_arm.S,v 1.2 2013/01/15 16:52:35 matt Exp $")
 
 #ifdef __ARMEL__
 #define        BYTE0   0x000000ff
@@ -92,8 +92,6 @@
         */
        mvns    ip, ip                  /* did we encounter a NUL? */
        beq     .Lfind_match            /*   no, find the match */
-       eors    r3, r3, ip              /* remove NUL bit */
-       beq     .Lnomatch               /*   if no other bits, no match */
        movs    ip, ip, lshi #8         /* replicate NUL bit to other bytes */
        orrne   ip, ip, lshi #8         /* replicate NUL bit to other bytes */
        orrne   ip, ip, lshi #8         /* replicate NUL bit to other bytes */
@@ -128,27 +126,30 @@
 
        sub     r2, r0, #4              /* un post-inc */
        mov     r0, #0                  /* assume no match */
-       tst     r3, #BYTE0              /* is this byte NUL? */
-       RETc(eq)                        /*   yes, return NULL */
+
        tst     ip, #BYTE0              /* does this byte match? */
        moveq   r0, r2                  /*   yes, point to it */
        RETc(eq)                        /*        and return */
+       tst     r3, #BYTE0              /* is this byte NUL? */
+       RETc(eq)                        /*   yes, return NULL */
+
+       tst     ip, #BYTE1              /* does this byte match? */
+       addeq   r0, r2, #1              /*   yes, point to it */
+       RETc(eq)                        /*        and return */
        tst     r3, #BYTE1              /* is this byte NUL? */
        RETc(eq)                        /*   yes, return NULL */
-       tst     ip, #BYTE1              /* does this byte match? */
-       addeq   r0, r2, #1              /*   yes, point to it */
+
+       tst     ip, #BYTE2              /* does this byte match? */
+       addeq   r0, r2, #2              /*   yes, point to it */
        RETc(eq)                        /*        and return */
        tst     r3, #BYTE2              /* is this byte NUL? */
        RETc(eq)                        /*   yes, return NULL */
-       tst     ip, #BYTE2              /* does this byte match? */
-       addeq   r0, r2, #2              /*   yes, point to it */
-       RETc(eq)                        /*        and return */
-       tst     r3, #BYTE3              /* is this byte NUL? */
-       RETc(eq)                        /*   yes, return NULL */
+
+       tst     ip, #BYTE3              /* does this byte match? */
+       addeq   r0, r2, #3              /*   yes, point to it */
        /*
         * Since no NULs and no matches this must be the only case left.
         */
-       add     r0, r2, #3              /* point to it */
        RET                             /* return */
 #endif /* _ARM_ARCH_6 */
 END(strchr)