Module Name: src
Committed By: matt
Date: Tue Aug 20 08:06:30 UTC 2013
Modified Files:
src/common/lib/libc/arch/arm/string: strlen_arm.S
Log Message:
thumbify (part2)
To generate a diff of this commit:
cvs rdiff -u -r1.4 -r1.5 src/common/lib/libc/arch/arm/string/strlen_arm.S
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/common/lib/libc/arch/arm/string/strlen_arm.S
diff -u src/common/lib/libc/arch/arm/string/strlen_arm.S:1.4 src/common/lib/libc/arch/arm/string/strlen_arm.S:1.5
--- src/common/lib/libc/arch/arm/string/strlen_arm.S:1.4 Mon Aug 19 01:17:32 2013
+++ src/common/lib/libc/arch/arm/string/strlen_arm.S Tue Aug 20 08:06:30 2013
@@ -29,7 +29,11 @@
#include <machine/asm.h>
-RCSID("$NetBSD: strlen_arm.S,v 1.4 2013/08/19 01:17:32 matt Exp $")
+RCSID("$NetBSD: strlen_arm.S,v 1.5 2013/08/20 08:06:30 matt Exp $")
+
+#if defined(__thumb__) && !defined(_ARM_ARCH_T2)
+#error Only Thumb2 or ARM supported
+#endif
#ifdef __ARMEL__
#define BYTE0 0x000000ff
@@ -63,10 +67,10 @@ ENTRY(FUNCNAME)
.cfi_offset 5, -4
.cfi_offset 4, -8
#endif
- add r5, r0, r1 /* get ptr to end of string */
+ adds r5, r0, r1 /* get ptr to end of string */
mov r4, r1 /* save maxlen */
#endif
- add ip, r0, #4 /* for the final post-inc */
+ adds r2, r0, #4 /* for the final post-inc */
1: tst r0, #3 /* test for word alignment */
beq .Lpre_main_loop /* finally word aligned */
#ifdef STRNLEN
@@ -74,10 +78,10 @@ ENTRY(FUNCNAME)
beq .Lmaxed_out /* yes, return maxlen */
#endif
ldrb r3, [r0], #1 /* load a byte */
- teq r3, #0 /* is it 0? */
+ cmp r3, #0 /* is it 0? */
bne 1b /* no, try next byte */
- sub ip, ip, #3 /* subtract (4 - the NUL) */
- sub r0, r0, ip /* subtract start */
+ subs r2, r2, #3 /* subtract (4 - the NUL) */
+ subs r0, r0, r2 /* subtract start */
#ifdef STRNLEN
pop {r4, r5} /* restore registers */
#endif
@@ -127,7 +131,12 @@ ENTRY(FUNCNAME)
rev r3, r3 /* we want this in BE for the CLZ */
#endif
clz r3, r3 /* count how many leading zeros */
+#ifdef __thumb__
+ lsrs r3, r3, #3
+ adds r0, r0, r3 /* divide that by 8 and add to count */
+#else
add r0, r0, r3, lsr #3 /* divide that by 8 and add to count */
+#endif
#else
/*
* We encountered a NUL.
@@ -147,7 +156,7 @@ ENTRY(FUNCNAME)
* start of the string (which also has 4 added to it to compensate for
* the post-inc.
*/
- sub r0, r0, ip /* subtract start to get length */
+ subs r0, r0, r2 /* subtract start to get length */
#ifdef STRNLEN
cmp r0, r4 /* is it larger than maxlen? */
movgt r0, r4 /* yes, return maxlen */
