diff options
Diffstat (limited to 'libc')
| -rw-r--r-- | libc/string/generic/strlen.c | 21 |
1 files changed, 2 insertions, 19 deletions
diff --git a/libc/string/generic/strlen.c b/libc/string/generic/strlen.c index dc383398b..dcc032ddc 100644 --- a/libc/string/generic/strlen.c +++ b/libc/string/generic/strlen.c @@ -28,7 +28,7 @@ size_t strlen (const char *str) { const char *char_ptr; const unsigned long int *longword_ptr; - unsigned long int longword, magic_bits, himagic, lomagic; + unsigned long int longword, himagic, lomagic; /* Handle the first few characters by reading one character at a time. Do this until CHAR_PTR is aligned on a longword boundary. */ @@ -52,14 +52,12 @@ size_t strlen (const char *str) The 1-bits make sure that carries propagate to the next 0-bit. The 0-bits provide holes for carries to fall into. */ - magic_bits = 0x7efefeffL; himagic = 0x80808080L; lomagic = 0x01010101L; if (sizeof (longword) > 4) { /* 64-bit version of the magic. */ /* Do the shift in two steps to avoid a warning if long has 32 bits. */ - magic_bits = ((0x7efefefeL << 16) << 16) | 0xfefefeffL; himagic = ((himagic << 16) << 16) | himagic; lomagic = ((lomagic << 16) << 16) | lomagic; } @@ -102,22 +100,7 @@ size_t strlen (const char *str) longword = *longword_ptr++; - if ( -#if 0 - /* Add MAGIC_BITS to LONGWORD. */ - (((longword + magic_bits) - - /* Set those bits that were unchanged by the addition. */ - ^ ~longword) - - /* Look at only the hole bits. If any of the hole bits - are unchanged, most likely one of the bytes was a - zero. */ - & ~magic_bits) -#else - ((longword - lomagic) & himagic) -#endif - != 0) + if (((longword - lomagic) & himagic) != 0) { /* Which of the bytes was the zero? If none of them were, it was a misfire; continue the search. */ |