diff options
| author | Michal Nazarewicz <mina86@mina86.com> | 2016-08-03 03:52:49 +0200 |
|---|---|---|
| committer | Michal Nazarewicz <mina86@mina86.com> | 2016-09-09 03:07:15 +0200 |
| commit | 0e7eb64076c17b3252249aa2a3ef340ce9f395bb (patch) | |
| tree | 339f048596ba216d0ba15808a3121515853189b5 | |
| parent | c579b28f6281c9cc0b711a012c30bf00036c60bf (diff) | |
Remove dead loop iterations in regex.c
RE_CHAR_TO_MULTIBYTE(c) yields c for ASCII characters and a byte8
character for c ≥ 0x80. Furthermore, CHAR_BYTE8_P(c) is true only
for byte8 characters. This means that
c = RE_CHAR_TO_MULTIBYTE (ch);
if (! CHAR_BYTE8_P (c) && re_iswctype (c, cc))
is equivalent to:
c = c;
if (! false && re_iswctype (c, cc))
for 0 ⪬ c < 0x80, and
c = BYTE8_TO_CHAR (c);
if (! true && re_iswctype (c, cc))
for 0x80 ⪬ c < 0x100. In other words, the loop never executes for
c ≥ 0x80 and RE_CHAR_TO_MULTIBYTE call is unnecessary for c < 0x80.
* src/regex.c (regex_compile): Simplyfy a for loop by eliminating
dead iterations and unnecessary macro calls.
| -rw-r--r-- | src/regex.c | 28 |
1 files changed, 12 insertions, 16 deletions
diff --git a/src/regex.c b/src/regex.c index 5f51b43e6c..41c1d3f610 100644 --- a/src/regex.c +++ b/src/regex.c @@ -2888,22 +2888,18 @@ regex_compile (const_re_char *pattern, size_t size, done until now. */ SETUP_BUFFER_SYNTAX_TABLE (); - for (ch = 0; ch < 256; ++ch) - { - c = RE_CHAR_TO_MULTIBYTE (ch); - if (! CHAR_BYTE8_P (c) - && re_iswctype (c, cc)) - { - SET_LIST_BIT (ch); - c1 = TRANSLATE (c); - if (c1 == c) - continue; - if (ASCII_CHAR_P (c1)) - SET_LIST_BIT (c1); - else if ((c1 = RE_CHAR_TO_UNIBYTE (c1)) >= 0) - SET_LIST_BIT (c1); - } - } + for (c = 0; c < 0x80; ++c) + if (re_iswctype (c, cc)) + { + SET_LIST_BIT (c); + c1 = TRANSLATE (c); + if (c1 == c) + continue; + if (ASCII_CHAR_P (c1)) + SET_LIST_BIT (c1); + else if ((c1 = RE_CHAR_TO_UNIBYTE (c1)) >= 0) + SET_LIST_BIT (c1); + } SET_RANGE_TABLE_WORK_AREA_BIT (range_table_work, re_wctype_to_bit (cc)); #endif /* emacs */ |