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Merged
kddnewton merged 1 commit into from
Mar 11, 2026
Merged

Improve pm_regexp_classify_property perf #3989

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84 changes: 54 additions & 30 deletions src/regexp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -430,15 +430,6 @@ typedef enum {
PM_REGEXP_PROPERTY_UNICODE
} pm_regexp_property_type_t;

/**
* Check if a property name matches a NUL-terminated target string
* (case-insensitive, exact length match).
*/
static inline bool
pm_regexp_property_name_matches(const uint8_t *name, size_t length, const char *target) {
return strlen(target) == length && pm_strncasecmp(name, (const uint8_t *) target, length) == 0;
}

/**
* Classify a property name. The name may start with '^' for negation, which
* is skipped before matching.
Expand All @@ -451,30 +442,63 @@ pm_regexp_classify_property(const uint8_t *name, size_t length) {
length--;
}

// POSIX properties — valid in all encodings.
static const char *const posix_properties[] = {
"Alnum", "Alpha", "ASCII", "Blank", "Cntrl", "Digit", "Graph",
"Lower", "Print", "Punct", "Space", "Upper", "XDigit", "Word",
NULL
};
#define PM_REGEXP_CASECMP(str_) (pm_strncasecmp(name, (const uint8_t *) (str_), length) == 0)

for (const char *const *property = posix_properties; *property != NULL; property++) {
if (pm_regexp_property_name_matches(name, length, *property)) {
return PM_REGEXP_PROPERTY_POSIX;
}
switch (length) {
case 3:
if (PM_REGEXP_CASECMP("Han")) return PM_REGEXP_PROPERTY_SCRIPT;
break;
case 4:
if (PM_REGEXP_CASECMP("Word")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 5:
/* Most properties are length 5, so dispatch on first character. */
switch (name[0] | 0x20) {
case 'a':
if (PM_REGEXP_CASECMP("Alnum")) return PM_REGEXP_PROPERTY_POSIX;
if (PM_REGEXP_CASECMP("Alpha")) return PM_REGEXP_PROPERTY_POSIX;
if (PM_REGEXP_CASECMP("ASCII")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 'b':
if (PM_REGEXP_CASECMP("Blank")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 'c':
if (PM_REGEXP_CASECMP("Cntrl")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 'd':
if (PM_REGEXP_CASECMP("Digit")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 'g':
if (PM_REGEXP_CASECMP("Graph")) return PM_REGEXP_PROPERTY_POSIX;
if (PM_REGEXP_CASECMP("Greek")) return PM_REGEXP_PROPERTY_SCRIPT;
break;
case 'l':
if (PM_REGEXP_CASECMP("Lower")) return PM_REGEXP_PROPERTY_POSIX;
if (PM_REGEXP_CASECMP("Latin")) return PM_REGEXP_PROPERTY_SCRIPT;
break;
case 'p':
if (PM_REGEXP_CASECMP("Print")) return PM_REGEXP_PROPERTY_POSIX;
if (PM_REGEXP_CASECMP("Punct")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 's':
if (PM_REGEXP_CASECMP("Space")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 'u':
if (PM_REGEXP_CASECMP("Upper")) return PM_REGEXP_PROPERTY_POSIX;
break;
}
break;
case 6:
if (PM_REGEXP_CASECMP("XDigit")) return PM_REGEXP_PROPERTY_POSIX;
break;
case 8:
if (PM_REGEXP_CASECMP("Hiragana")) return PM_REGEXP_PROPERTY_SCRIPT;
if (PM_REGEXP_CASECMP("Katakana")) return PM_REGEXP_PROPERTY_SCRIPT;
if (PM_REGEXP_CASECMP("Cyrillic")) return PM_REGEXP_PROPERTY_SCRIPT;
break;
}

// Script properties — valid in /e, /s, /u but not /n.
static const char *const script_properties[] = {
"Hiragana", "Katakana", "Han", "Latin", "Greek", "Cyrillic",
NULL
};

for (const char *const *property = script_properties; *property != NULL; property++) {
if (pm_regexp_property_name_matches(name, length, *property)) {
return PM_REGEXP_PROPERTY_SCRIPT;
}
}
#undef PM_REGEXP_CASECMP

// Everything else is Unicode-only (general categories, other scripts, etc.).
return PM_REGEXP_PROPERTY_UNICODE;
Expand Down