[src/trunk]: src/common/lib/libc/arch/arm/string Thumbify

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

details:   https://anonhg.NetBSD.org/src/rev/59ae599e9d3d
branches:  trunk
changeset: 789437:59ae599e9d3d
user:      matt <matt%NetBSD.org@localhost>
date:      Mon Aug 19 02:36:27 2013 +0000

description:
Thumbify

diffstat:

 common/lib/libc/arch/arm/string/strrchr_naive.S |  20 ++++++++++++++++++--
 1 files changed, 18 insertions(+), 2 deletions(-)

diffs (39 lines):

diff -r 50882a3ac7e5 -r 59ae599e9d3d common/lib/libc/arch/arm/string/strrchr_naive.S
--- a/common/lib/libc/arch/arm/string/strrchr_naive.S   Mon Aug 19 02:24:09 2013 +0000
+++ b/common/lib/libc/arch/arm/string/strrchr_naive.S   Mon Aug 19 02:36:27 2013 +0000
@@ -28,17 +28,33 @@
  */
 #include <machine/asm.h>
 
-RCSID("$NetBSD: strrchr_naive.S,v 1.2 2013/08/19 02:24:09 matt Exp $")
+RCSID("$NetBSD: strrchr_naive.S,v 1.3 2013/08/19 02:36:27 matt Exp $")
 
 /* LINTSTUB: char * strrchr(const char *, int) */
 ENTRY(strrchr)
        mov     r2, r0          /* using r0 as return value */
-       mov     r0, #0          /* default to no match */
+       movs    r0, #0          /* default to no match */
+#ifdef __thumb__
+       movs    r3, #0xff
+       ands    r1, r1, r3      /* restrict to a byte value */
+1:     ldrb    r3, [r2]        /* read a byte */
+       cmp     r3, r1          /* does it match? */
+       bne     2f              /*   no, go and advance */
+       mov     r0, r2          /*   yes, set return value to point to it */
+2:     adds    r2, r2, #1      /* advance to next byte */
+#ifdef _ARM_ARCH_T2
+       cbnz    r3, 1b          /* was it a NUL?  no, get next byte */
+#else
+       cmp     r3, #0          /* was it a NUL? */
+       bne     1b              /*   no, get next byte */
+#endif
+#else
        and     r1, r1, #0xff   /* restrict to a byte value */
 1:     ldrb    r3, [r2], #1    /* read a byte */
        cmp     r3, r1          /* does it match? */
        subeq   r0, r2, #1      /*   yes, set return value to point to it */
        cmp     r3, #0          /* was it a NUL? */
        bne     1b              /*   no, get next byte */
+#endif
        RET
 END(strrchr)