wctype simplifications.
Remove the unused bogus entry from the array in wctype(), and switch from a switch statement to an array in iswctype(). Oddly (to me) clang is currently completely unrolling the loop in wctype(), which seems pointless, but not recognizing that the switch in iswctype() is just a jump table.
This doesn't change the generated code for wctype() except for removing one unnecessary strcmp() from every invocation, but it changes iswctype() to the optimal code you'd write by hand.
Change-Id: Ib2ac61442c7621288a73f7324d795cf054a60ea5
diff --git a/libc/bionic/wctype.cpp b/libc/bionic/wctype.cpp
index 082dada..be0f878 100644
--- a/libc/bionic/wctype.cpp
+++ b/libc/bionic/wctype.cpp
@@ -34,6 +34,7 @@
#include <string.h>
#include <wchar.h>
+#include "bionic/macros.h"
#include "private/icu.h"
enum {
@@ -95,21 +96,12 @@
int iswxdigit_l(wint_t c, locale_t) { return iswxdigit(c); }
int iswctype(wint_t wc, wctype_t char_class) {
- switch (char_class) {
- case WC_TYPE_ALNUM: return iswalnum(wc);
- case WC_TYPE_ALPHA: return iswalpha(wc);
- case WC_TYPE_BLANK: return iswblank(wc);
- case WC_TYPE_CNTRL: return iswcntrl(wc);
- case WC_TYPE_DIGIT: return iswdigit(wc);
- case WC_TYPE_GRAPH: return iswgraph(wc);
- case WC_TYPE_LOWER: return iswlower(wc);
- case WC_TYPE_PRINT: return iswprint(wc);
- case WC_TYPE_PUNCT: return iswpunct(wc);
- case WC_TYPE_SPACE: return iswspace(wc);
- case WC_TYPE_UPPER: return iswupper(wc);
- case WC_TYPE_XDIGIT: return iswxdigit(wc);
- default: return 0;
- }
+ if (char_class < WC_TYPE_ALNUM || char_class > WC_TYPE_XDIGIT) return 0;
+ static int (*fns[])(wint_t) = {
+ iswalnum, iswalpha, iswblank, iswcntrl, iswdigit, iswgraph,
+ iswlower, iswprint, iswpunct, iswspace, iswupper, iswxdigit
+ };
+ return fns[char_class - WC_TYPE_ALNUM](wc);
}
int iswctype_l(wint_t wc, wctype_t char_class, locale_t) {
@@ -144,14 +136,13 @@
wint_t towlower_l(wint_t c, locale_t) { return towlower(c); }
wctype_t wctype(const char* property) {
- static const char* const properties[WC_TYPE_MAX] = {
- "<invalid>",
+ static const char* const properties[WC_TYPE_MAX - 1] = {
"alnum", "alpha", "blank", "cntrl", "digit", "graph",
"lower", "print", "punct", "space", "upper", "xdigit"
};
- for (size_t i = 0; i < WC_TYPE_MAX; ++i) {
+ for (size_t i = 0; i < arraysize(properties); ++i) {
if (!strcmp(properties[i], property)) {
- return static_cast<wctype_t>(i);
+ return static_cast<wctype_t>(WC_TYPE_ALNUM + i);
}
}
return static_cast<wctype_t>(0);