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| author | Jeff Johnston <jjohnstn@redhat.com> | 2009-03-16 20:12:30 +0000 |
|---|---|---|
| committer | Jeff Johnston <jjohnstn@redhat.com> | 2009-03-16 20:12:30 +0000 |
| commit | d70118655b0d30849c5a85e2afbb72b91e395a63 (patch) | |
| tree | fba90704b6bcbd7c14def7c3b1d105a49c9ed564 /newlib/libc/machine/arm/strlen.c | |
| parent | 8213c3f8e3e8e9276e27d6920ff2008ed234e4a3 (diff) | |
| download | cygnal-d70118655b0d30849c5a85e2afbb72b91e395a63.tar.gz cygnal-d70118655b0d30849c5a85e2afbb72b91e395a63.tar.bz2 cygnal-d70118655b0d30849c5a85e2afbb72b91e395a63.zip | |
2009-03-16 Mark Mitchell <mark@codesourcery.com>
* libc/machine/arm/strlen.c (strlen): Fix defect in Thumb-2 mode.
2009-03-16 Richard Earnshaw <rearnsha@arm.com>
* libc/machine/arm/strlen.c (strlen): Correctly detect
end-of-string.
* libc/machine/arm/strcpy.c (strcpy): Likewise.
* libc/machine/arm/strcmp.c (strcmp, strcmp_unaligned): Likewise.
Diffstat (limited to 'newlib/libc/machine/arm/strlen.c')
| -rw-r--r-- | newlib/libc/machine/arm/strlen.c | 19 |
1 files changed, 11 insertions, 8 deletions
diff --git a/newlib/libc/machine/arm/strlen.c b/newlib/libc/machine/arm/strlen.c index 6442c77ed..f31f72170 100644 --- a/newlib/libc/machine/arm/strlen.c +++ b/newlib/libc/machine/arm/strlen.c @@ -79,16 +79,17 @@ strlen (const char* str) "add ip, len, #4\n\t" "mov ip, ip, asl #3\n\t" "mvn r2, #0\n\t" - "it ne\n\t" /* ... are masked out */ #ifdef __thumb__ + "itt ne\n\t" # ifdef __ARMEB__ "lslne r2, ip\n\t" # else "lsrne r2, ip\n\t" # endif - "orr data, data, r2\n\t" + "orrne data, data, r2\n\t" #else + "it ne\n\t" # ifdef __ARMEB__ "orrne data, data, r2, lsl ip\n\t" # else @@ -104,13 +105,15 @@ strlen (const char* str) #endif "orr ip, ip, ip, lsl #16\n" - /* This is the main loop. We subtract one from each byte in the - word: the sign bit changes iff the byte was zero. */ + /* This is the main loop. We subtract one from each byte in + the word: the sign bit changes iff the byte was zero or + 0x80 -- we eliminate the latter case by anding the result + with the 1-s complement of the data. */ "1:\n\t" /* test (data - 0x01010101) */ "sub r2, data, ip\n\t" - /* ... ^ data */ - "eor r2, r2, data\n\t" + /* ... & ~data */ + "bic r2, r2, data\n\t" /* ... & 0x80808080 == 0? */ "ands r2, r2, ip, lsl #7\n\t" #ifdef _ISA_ARM_7 @@ -124,8 +127,8 @@ strlen (const char* str) /* test (data - 0x01010101) */ "ittt eq\n\t" "subeq r2, data, ip\n\t" - /* ... ^ data */ - "eoreq r2, r2, data\n\t" + /* ... & ~data */ + "biceq r2, r2, data\n\t" /* ... & 0x80808080 == 0? */ "andeqs r2, r2, ip, lsl #7\n\t" #endif |