Revision: 573
http://vcs.pcre.org/viewvc?view=rev&revision=573
Author: ph10
Date: 2010-11-19 19:29:44 +0000 (Fri, 19 Nov 2010)
Log Message:
-----------
Remove loops from GETCHAR etc. macros.
Modified Paths:
--------------
code/trunk/ChangeLog
code/trunk/pcre_internal.h
Modified: code/trunk/ChangeLog
===================================================================
--- code/trunk/ChangeLog 2010-11-17 17:55:57 UTC (rev 572)
+++ code/trunk/ChangeLog 2010-11-19 19:29:44 UTC (rev 573)
@@ -102,6 +102,12 @@
left --include_dir as an undocumented synonym, and the same for
--exclude-dir, though that is not available in GNU grep, at least as of
release 2.5.4.
+
+18. At a user's suggestion, the macros GETCHAR and friends (which pick up UTF-8
+ characters from a string of bytes) have been redefined so as not to use
+ loops, in order to improve performance in some environments. At the same
+ time, I abstracted some of the common code into auxiliary macros to save
+ repetition (this should not affect the compiled code).
Version 8.10 25-Jun-2010
Modified: code/trunk/pcre_internal.h
===================================================================
--- code/trunk/pcre_internal.h 2010-11-17 17:55:57 UTC (rev 572)
+++ code/trunk/pcre_internal.h 2010-11-19 19:29:44 UTC (rev 573)
@@ -408,9 +408,10 @@
/* When UTF-8 encoding is being used, a character is no longer just a single
byte. The macros for character handling generate simple sequences when used in
-byte-mode, and more complicated ones for UTF-8 characters. BACKCHAR should
-never be called in byte mode. To make sure it can never even appear when UTF-8
-support is omitted, we don't even define it. */
+byte-mode, and more complicated ones for UTF-8 characters. GETCHARLENTEST is
+not used when UTF-8 is not supported, so it is not defined, and BACKCHAR should
+never be called in byte mode. To make sure they can never even appear when
+UTF-8 support is omitted, we don't even define them. */
#ifndef SUPPORT_UTF8
#define GETCHAR(c, eptr) c = *eptr;
@@ -418,44 +419,84 @@
#define GETCHARINC(c, eptr) c = *eptr++;
#define GETCHARINCTEST(c, eptr) c = *eptr++;
#define GETCHARLEN(c, eptr, len) c = *eptr;
+/* #define GETCHARLENTEST(c, eptr, len) */
/* #define BACKCHAR(eptr) */
#else /* SUPPORT_UTF8 */
+/* These macros were originally written in the form of loops that used data
+from the tables whose names start with _pcre_utf8_table. They were rewritten by
+a user so as not to use loops, because in some environments this gives a
+significant performance advantage, and it seems never to do any harm. */
+
+/* Base macro to pick up the remaining bytes of a UTF-8 character, not
+advancing the pointer. */
+
+#define GETUTF8(c, eptr) \
+ { \
+ if ((c & 0x20) == 0) \
+ c = ((c & 0x1f) << 6) | (eptr[1] & 0x3f); \
+ else if ((c & 0x10) == 0) \
+ c = ((c & 0x0f) << 12) | ((eptr[1] & 0x3f) << 6) | (eptr[2] & 0x3f); \
+ else if ((c & 0x08) == 0) \
+ c = ((c & 0x07) << 18) | ((eptr[1] & 0x3f) << 12) | \
+ ((eptr[2] & 0x3f) << 6) | (eptr[3] & 0x3f); \
+ else if ((c & 0x04) == 0) \
+ c = ((c & 0x03) << 24) | ((eptr[1] & 0x3f) << 18) | \
+ ((eptr[2] & 0x3f) << 12) | ((eptr[3] & 0x3f) << 6) | \
+ (eptr[4] & 0x3f); \
+ else \
+ c = ((c & 0x01) << 30) | ((eptr[1] & 0x3f) << 24) | \
+ ((eptr[2] & 0x3f) << 18) | ((eptr[3] & 0x3f) << 12) | \
+ ((eptr[4] & 0x3f) << 6) | (eptr[5] & 0x3f); \
+ }
+
/* Get the next UTF-8 character, not advancing the pointer. This is called when
we know we are in UTF-8 mode. */
#define GETCHAR(c, eptr) \
c = *eptr; \
- if (c >= 0xc0) \
- { \
- int gcii; \
- int gcaa = _pcre_utf8_table4[c & 0x3f]; /* Number of additional bytes */ \
- int gcss = 6*gcaa; \
- c = (c & _pcre_utf8_table3[gcaa]) << gcss; \
- for (gcii = 1; gcii <= gcaa; gcii++) \
- { \
- gcss -= 6; \
- c |= (eptr[gcii] & 0x3f) << gcss; \
- } \
- }
+ if (c >= 0xc0) GETUTF8(c, eptr);
/* Get the next UTF-8 character, testing for UTF-8 mode, and not advancing the
pointer. */
#define GETCHARTEST(c, eptr) \
c = *eptr; \
- if (utf8 && c >= 0xc0) \
+ if (utf8 && c >= 0xc0) GETUTF8(c, eptr);
+
+/* Base macro to pick up the remaining bytes of a UTF-8 character, advancing
+the pointer. */
+
+#define GETUTF8INC(c, eptr) \
{ \
- int gcii; \
- int gcaa = _pcre_utf8_table4[c & 0x3f]; /* Number of additional bytes */ \
- int gcss = 6*gcaa; \
- c = (c & _pcre_utf8_table3[gcaa]) << gcss; \
- for (gcii = 1; gcii <= gcaa; gcii++) \
+ if ((c & 0x20) == 0) \
+ c = ((c & 0x1f) << 6) | (*eptr++ & 0x3f); \
+ else if ((c & 0x10) == 0) \
{ \
- gcss -= 6; \
- c |= (eptr[gcii] & 0x3f) << gcss; \
+ c = ((c & 0x0f) << 12) | ((*eptr & 0x3f) << 6) | (eptr[1] & 0x3f); \
+ eptr += 2; \
} \
+ else if ((c & 0x08) == 0) \
+ { \
+ c = ((c & 0x07) << 18) | ((*eptr & 0x3f) << 12) | \
+ ((eptr[1] & 0x3f) << 6) | (eptr[2] & 0x3f); \
+ eptr += 3; \
+ } \
+ else if ((c & 0x04) == 0) \
+ { \
+ c = ((c & 0x03) << 24) | ((*eptr & 0x3f) << 18) | \
+ ((eptr[1] & 0x3f) << 12) | ((eptr[2] & 0x3f) << 6) | \
+ (eptr[3] & 0x3f); \
+ eptr += 4; \
+ } \
+ else \
+ { \
+ c = ((c & 0x01) << 30) | ((*eptr & 0x3f) << 24) | \
+ ((eptr[1] & 0x3f) << 18) | ((eptr[2] & 0x3f) << 12) | \
+ ((eptr[3] & 0x3f) << 6) | (eptr[4] & 0x3f); \
+ eptr += 5; \
+ } \
}
/* Get the next UTF-8 character, advancing the pointer. This is called when we
@@ -463,33 +504,50 @@
#define GETCHARINC(c, eptr) \
c = *eptr++; \
- if (c >= 0xc0) \
- { \
- int gcaa = _pcre_utf8_table4[c & 0x3f]; /* Number of additional bytes */ \
- int gcss = 6*gcaa; \
- c = (c & _pcre_utf8_table3[gcaa]) << gcss; \
- while (gcaa-- > 0) \
- { \
- gcss -= 6; \
- c |= (*eptr++ & 0x3f) << gcss; \
- } \
- }
+ if (c >= 0xc0) GETUTF8INC(c, eptr);
/* Get the next character, testing for UTF-8 mode, and advancing the pointer.
This is called when we don't know if we are in UTF-8 mode. */
#define GETCHARINCTEST(c, eptr) \
c = *eptr++; \
- if (utf8 && c >= 0xc0) \
+ if (utf8 && c >= 0xc0) GETUTF8INC(c, eptr);
+
+/* Base macro to pick up the remaining bytes of a UTF-8 character, not
+advancing the pointer, incrementing the length. */
+
+#define GETUTF8LEN(c, eptr, len) \
{ \
- int gcaa = _pcre_utf8_table4[c & 0x3f]; /* Number of additional bytes */ \
- int gcss = 6*gcaa; \
- c = (c & _pcre_utf8_table3[gcaa]) << gcss; \
- while (gcaa-- > 0) \
+ if ((c & 0x20) == 0) \
{ \
- gcss -= 6; \
- c |= (*eptr++ & 0x3f) << gcss; \
+ c = ((c & 0x1f) << 6) | (eptr[1] & 0x3f); \
+ len++; \
} \
+ else if ((c & 0x10) == 0) \
+ { \
+ c = ((c & 0x0f) << 12) | ((eptr[1] & 0x3f) << 6) | (eptr[2] & 0x3f); \
+ len += 2; \
+ } \
+ else if ((c & 0x08) == 0) \
+ {\
+ c = ((c & 0x07) << 18) | ((eptr[1] & 0x3f) << 12) | \
+ ((eptr[2] & 0x3f) << 6) | (eptr[3] & 0x3f); \
+ len += 3; \
+ } \
+ else if ((c & 0x04) == 0) \
+ { \
+ c = ((c & 0x03) << 24) | ((eptr[1] & 0x3f) << 18) | \
+ ((eptr[2] & 0x3f) << 12) | ((eptr[3] & 0x3f) << 6) | \
+ (eptr[4] & 0x3f); \
+ len += 4; \
+ } \
+ else \
+ {\
+ c = ((c & 0x01) << 30) | ((eptr[1] & 0x3f) << 24) | \
+ ((eptr[2] & 0x3f) << 18) | ((eptr[3] & 0x3f) << 12) | \
+ ((eptr[4] & 0x3f) << 6) | (eptr[5] & 0x3f); \
+ len += 5; \
+ } \
}
/* Get the next UTF-8 character, not advancing the pointer, incrementing length
@@ -497,19 +555,7 @@
#define GETCHARLEN(c, eptr, len) \
c = *eptr; \
- if (c >= 0xc0) \
- { \
- int gcii; \
- int gcaa = _pcre_utf8_table4[c & 0x3f]; /* Number of additional bytes */ \
- int gcss = 6*gcaa; \
- c = (c & _pcre_utf8_table3[gcaa]) << gcss; \
- for (gcii = 1; gcii <= gcaa; gcii++) \
- { \
- gcss -= 6; \
- c |= (eptr[gcii] & 0x3f) << gcss; \
- } \
- len += gcaa; \
- }
+ if (c >= 0xc0) GETUTF8LEN(c, eptr, len);
/* Get the next UTF-8 character, testing for UTF-8 mode, not advancing the
pointer, incrementing length if there are extra bytes. This is called when we
@@ -517,19 +563,7 @@
#define GETCHARLENTEST(c, eptr, len) \
c = *eptr; \
- if (utf8 && c >= 0xc0) \
- { \
- int gcii; \
- int gcaa = _pcre_utf8_table4[c & 0x3f]; /* Number of additional bytes */ \
- int gcss = 6*gcaa; \
- c = (c & _pcre_utf8_table3[gcaa]) << gcss; \
- for (gcii = 1; gcii <= gcaa; gcii++) \
- { \
- gcss -= 6; \
- c |= (eptr[gcii] & 0x3f) << gcss; \
- } \
- len += gcaa; \
- }
+ if (utf8 && c >= 0xc0) GETUTF8LEN(c, eptr, len);
/* If the pointer is not at the start of a character, move it back until
it is. This is called only in UTF-8 mode - we don't put a test within the macro
@@ -537,7 +571,7 @@
#define BACKCHAR(eptr) while((*eptr & 0xc0) == 0x80) eptr--
-#endif
+#endif /* SUPPORT_UTF8 */
/* In case there is no definition of offsetof() provided - though any proper
