Revision: 1040
http://vcs.pcre.org/viewvc?view=rev&revision=1040
Author: zherczeg
Date: 2012-09-16 07:52:27 +0100 (Sun, 16 Sep 2012)
Log Message:
-----------
Improving the first n character searches.
Modified Paths:
--------------
code/trunk/ChangeLog
code/trunk/pcre_jit_compile.c
Modified: code/trunk/ChangeLog
===================================================================
--- code/trunk/ChangeLog 2012-09-13 16:39:03 UTC (rev 1039)
+++ code/trunk/ChangeLog 2012-09-16 06:52:27 UTC (rev 1040)
@@ -81,7 +81,9 @@
substrings matched by the 1st and 2nd capturing parentheses. A separating
string can be specified by --om-separator (default empty).
+19. Improving the first n character searches.
+
Version 8.31 06-July-2012
-------------------------
Modified: code/trunk/pcre_jit_compile.c
===================================================================
--- code/trunk/pcre_jit_compile.c 2012-09-13 16:39:03 UTC (rev 1039)
+++ code/trunk/pcre_jit_compile.c 2012-09-16 06:52:27 UTC (rev 1040)
@@ -2563,47 +2563,37 @@
return mainloop;
}
-static SLJIT_INLINE BOOL fast_forward_first_two_chars(compiler_common *common, BOOL firstline)
+#define MAX_N_CHARS 3
+
+static SLJIT_INLINE BOOL fast_forward_first_n_chars(compiler_common *common, BOOL firstline)
{
DEFINE_COMPILER;
struct sljit_label *start;
struct sljit_jump *quit;
-struct sljit_jump *found;
-pcre_int32 chars[4];
+pcre_int32 chars[MAX_N_CHARS * 2];
pcre_uchar *cc = common->start + 1 + IMM2_SIZE;
int location = 0;
pcre_int32 len, c, bit, caseless;
-BOOL must_end;
+int must_stop;
-#ifdef COMPILE_PCRE8
-union {
- sljit_uh ascombined;
- sljit_ub asuchars[2];
-} pair;
-#else
-union {
- sljit_ui ascombined;
- sljit_uh asuchars[2];
-} pair;
-#endif
-
+/* We do not support alternatives now. */
if (*(common->start + GET(common->start, 1)) == OP_ALT)
return FALSE;
while (TRUE)
{
caseless = 0;
- must_end = TRUE;
+ must_stop = 1;
switch(*cc)
{
case OP_CHAR:
- must_end = FALSE;
+ must_stop = 0;
cc++;
break;
case OP_CHARI:
caseless = 1;
- must_end = FALSE;
+ must_stop = 0;
cc++;
break;
@@ -2645,9 +2635,13 @@
break;
default:
- return FALSE;
+ must_stop = 2;
+ break;
}
+ if (must_stop == 2)
+ break;
+
len = 1;
#ifdef SUPPORT_UTF
if (common->utf && HAS_EXTRALEN(cc[0])) len += GET_EXTRALEN(cc[0]);
@@ -2670,7 +2664,7 @@
else
caseless = 0;
- while (len > 0 && location < 2 * 2)
+ while (len > 0 && location < MAX_N_CHARS * 2)
{
c = *cc;
bit = 0;
@@ -2688,72 +2682,56 @@
cc++;
}
- if (location == 2 * 2)
+ if (location >= MAX_N_CHARS * 2 || must_stop != 0)
break;
- else if (must_end)
- return FALSE;
}
+/* At least two characters are required. */
+if (location < 2 * 2)
+ return FALSE;
+
if (firstline)
{
SLJIT_ASSERT(common->first_line_end != 0);
OP1(SLJIT_MOV, TMP3, 0, STR_END, 0);
- OP2(SLJIT_SUB, STR_END, 0, SLJIT_MEM1(SLJIT_LOCALS_REG), common->first_line_end, SLJIT_IMM, 1);
+ OP2(SLJIT_SUB, STR_END, 0, SLJIT_MEM1(SLJIT_LOCALS_REG), common->first_line_end, SLJIT_IMM, (location >> 1) - 1);
}
else
- OP2(SLJIT_SUB, STR_END, 0, STR_END, 0, SLJIT_IMM, 1);
+ OP2(SLJIT_SUB, STR_END, 0, STR_END, 0, SLJIT_IMM, (location >> 1) - 1);
start = LABEL();
quit = CMP(SLJIT_C_GREATER_EQUAL, STR_PTR, 0, STR_END, 0);
-#if defined SLJIT_UNALIGNED && SLJIT_UNALIGNED
-#ifdef COMPILE_PCRE8
-OP1(SLJIT_MOV_UH, TMP1, 0, SLJIT_MEM1(STR_PTR), 0);
-#else /* COMPILE_PCRE8 */
-OP1(SLJIT_MOV_UI, TMP1, 0, SLJIT_MEM1(STR_PTR), 0);
-#endif
-#else /* SLJIT_UNALIGNED */
-
-#if defined SLJIT_BIG_ENDIAN && SLJIT_BIG_ENDIAN
-OP1(MOV_UCHAR, TMP2, 0, SLJIT_MEM1(STR_PTR), 0);
-OP1(MOV_UCHAR, TMP1, 0, SLJIT_MEM1(STR_PTR), IN_UCHARS(1));
-#else /* SLJIT_BIG_ENDIAN */
+OP1(MOV_UCHAR, TMP1, 0, SLJIT_MEM1(STR_PTR), IN_UCHARS(0));
OP1(MOV_UCHAR, TMP2, 0, SLJIT_MEM1(STR_PTR), IN_UCHARS(1));
-OP1(MOV_UCHAR, TMP1, 0, SLJIT_MEM1(STR_PTR), 0);
-#endif /* SLJIT_BIG_ENDIAN */
-
-#ifdef COMPILE_PCRE8
-OP2(SLJIT_SHL, TMP2, 0, TMP2, 0, SLJIT_IMM, 8);
-#else /* COMPILE_PCRE8 */
-OP2(SLJIT_SHL, TMP2, 0, TMP2, 0, SLJIT_IMM, 16);
-#endif
-OP2(SLJIT_OR, TMP1, 0, TMP1, 0, TMP2, 0);
-
-#endif
-
-if (chars[1] != 0 || chars[3] != 0)
+OP2(SLJIT_ADD, STR_PTR, 0, STR_PTR, 0, SLJIT_IMM, IN_UCHARS(1));
+if (chars[1] != 0)
+ OP2(SLJIT_OR, TMP1, 0, TMP1, 0, SLJIT_IMM, chars[1]);
+CMPTO(SLJIT_C_NOT_EQUAL, TMP1, 0, SLJIT_IMM, chars[0], start);
+if (location > 2 * 2)
+ OP1(MOV_UCHAR, TMP1, 0, SLJIT_MEM1(STR_PTR), IN_UCHARS(1));
+if (chars[3] != 0)
+ OP2(SLJIT_OR, TMP2, 0, TMP2, 0, SLJIT_IMM, chars[3]);
+CMPTO(SLJIT_C_NOT_EQUAL, TMP2, 0, SLJIT_IMM, chars[2], start);
+if (location > 2 * 2)
{
- pair.asuchars[0] = chars[1];
- pair.asuchars[1] = chars[3];
- OP2(SLJIT_OR, TMP1, 0, TMP1, 0, SLJIT_IMM, pair.ascombined);
+ if (chars[5] != 0)
+ OP2(SLJIT_OR, TMP1, 0, TMP1, 0, SLJIT_IMM, chars[5]);
+ CMPTO(SLJIT_C_NOT_EQUAL, TMP1, 0, SLJIT_IMM, chars[4], start);
}
+OP2(SLJIT_SUB, STR_PTR, 0, STR_PTR, 0, SLJIT_IMM, IN_UCHARS(1));
-pair.asuchars[0] = chars[0];
-pair.asuchars[1] = chars[2];
-found = CMP(SLJIT_C_EQUAL, TMP1, 0, SLJIT_IMM, pair.ascombined);
-
-OP2(SLJIT_ADD, STR_PTR, 0, STR_PTR, 0, SLJIT_IMM, IN_UCHARS(1));
-JUMPTO(SLJIT_JUMP, start);
-JUMPHERE(found);
JUMPHERE(quit);
if (firstline)
OP1(SLJIT_MOV, STR_END, 0, TMP3, 0);
else
- OP2(SLJIT_ADD, STR_END, 0, STR_END, 0, SLJIT_IMM, 1);
+ OP2(SLJIT_ADD, STR_END, 0, STR_END, 0, SLJIT_IMM, (location >> 1) - 1);
return TRUE;
}
+#undef MAX_N_CHARS
+
static SLJIT_INLINE void fast_forward_first_char(compiler_common *common, pcre_uchar first_char, BOOL caseless, BOOL firstline)
{
DEFINE_COMPILER;
@@ -7916,7 +7894,7 @@
/* Forward search if possible. */
if ((re->options & PCRE_NO_START_OPTIMIZE) == 0)
{
- if (mode == JIT_COMPILE && fast_forward_first_two_chars(common, (re->options & PCRE_FIRSTLINE) != 0))
+ if (mode == JIT_COMPILE && fast_forward_first_n_chars(common, (re->options & PCRE_FIRSTLINE) != 0))
{ /* Do nothing */ }
else if ((re->flags & PCRE_FIRSTSET) != 0)
fast_forward_first_char(common, (pcre_uchar)re->first_char, (re->flags & PCRE_FCH_CASELESS) != 0, (re->options & PCRE_FIRSTLINE) != 0);
