* XXX khw thinks this should be enhanced to fill EXACT (at least) nodes as full
* as possible, even if that means splitting an existing node so that its first
* part is moved to the preceeding node. This would maximise the efficiency of
- * memEQ during matching. Elsewhere in this file, khw proposes splitting
- * EXACTFish nodes into portions that don't change under folding vs those that
- * do. Those portions that don't change may be the only things in the pattern that
- * could be used to find fixed and floating strings.
+ * memEQ during matching.
*
* If a node is to match under /i (folded), the number of characters it matches
* can be different than its character length if it contains a multi-character
char *s0;
U8 upper_parse = MAX_NODE_STRING_SIZE;
- U8 node_type = compute_EXACTish(pRExC_state);
+
+ /* We start out as an EXACT node, even if under /i, until we find a
+ * character which is in a fold. The algorithm now segregates into
+ * separate nodes, characters that fold from those that don't under
+ * /i. (This hopefull will create nodes that are fixed strings
+ * even under /i, giving the optimizer something to grab onto to.)
+ * So, if a node has something in it and the next character is in
+ * the opposite category, that node is closed up, and the function
+ * returns. Then regatom is called again, and a new node is
+ * created for the new category. */
+ U8 node_type = EXACT;
+
bool next_is_quantifier;
char * oldp = NULL;
* which don't participate in folds with Latin1-range characters,
* as the latter's folds aren't known until runtime. (We don't
* need to figure this out until pass 2) */
- bool maybe_exactfu = PASS2
- && (node_type == EXACTF || node_type == EXACTFL);
-
- /* If a folding node contains only code points that don't
- * participate in folds, it can be changed into an EXACT node,
- * which allows the optimizer more things to look for, and is
- * faster to match */
- bool maybe_exact;
+ bool maybe_exactfu = PASS2;
/* The node_type may change below, but since the size of the node
* doesn't change, it works */
reparse:
- /* We look for the EXACTFish to EXACT node optimizaton only if
- * folding. (And we don't need to figure this out until pass 2).
- * XXX It might actually make sense to split the node into portions
- * that are exact and ones that aren't, so that we could later use
- * the exact ones to find the longest fixed and floating strings.
- * One would want to join them back into a larger node. One could
- * use a pseudo regnode like 'EXACT_ORIG_FOLD' */
- maybe_exact = FOLD && PASS2;
-
/* This breaks under rare circumstances. If folding, we do not
* want to split a node at a character that is a non-final in a
* multi-char fold, as an input string could just happen to want to
/* Here, we have a literal character. Find the maximal string of
* them in the input that we can fit into a single EXACTish node.
- * We quit at the first non-literal or when the node gets full */
+ * We quit at the first non-literal or when the node gets full, or
+ * under /i the categorization of folding/non-folding character
+ * changes */
for (p = RExC_parse; len < upper_parse && p < RExC_end; ) {
/* In most cases each iteration adds one byte to the output.
else if (LOC && is_PROBLEMATIC_LOCALE_FOLD_cp(ender)) {
/* Here are folding under /l, and the code point is
- * problematic. First, we know we can't simplify things */
- maybe_exact = FALSE;
+ * problematic. If this is the first character in the
+ * node, change the node type to folding. Otherwise, if
+ * this is the first problematic character, close up the
+ * existing node, so can start a new node with this one */
+ if (! len) {
+ node_type = EXACTFL;
+ }
+ else if (node_type == EXACT) {
+ p = oldp;
+ goto loopdone;
+ }
/* This code point means we can't simplify things */
maybe_exactfu = FALSE;
* do for both passes is the PASS2 code for non-folding */
goto not_fold_common;
}
- else /* A regular FOLD code point */
- if (! ( UTF
-#if UNICODE_MAJOR_VERSION > 3 /* no multifolds in early Unicode */ \
- || (UNICODE_MAJOR_VERSION == 3 && ( UNICODE_DOT_VERSION > 0) \
- || UNICODE_DOT_DOT_VERSION > 0)
- /* See comments for join_exact() as to why we fold
- * this non-UTF at compile time */
- || ( node_type == EXACTFU
- && ender == LATIN_SMALL_LETTER_SHARP_S)
-#endif
- )) {
+ else /* A regular FOLD code point */
+ if (! UTF)
+ {
/* Here, are folding and are not UTF-8 encoded; therefore
* the character must be in the range 0-255, and is not /l.
* (Not /l because we already handled these under /l in
* is_PROBLEMATIC_LOCALE_FOLD_cp) */
- if (IS_IN_SOME_FOLD_L1(ender)) {
- maybe_exact = FALSE;
+ if (! IS_IN_SOME_FOLD_L1(ender)) {
- /* See if the character's fold differs between /d and
- * /u. This includes the multi-char fold SHARP S to
- * 'ss' */
- if (UNLIKELY(ender == LATIN_SMALL_LETTER_SHARP_S)) {
- RExC_seen_unfolded_sharp_s = 1;
- maybe_exactfu = FALSE;
+ /* Start a new node for this non-folding character if
+ * previous ones in the node were folded */
+ if (len && node_type != EXACT) {
+ p = oldp;
+ goto loopdone;
}
- else if (maybe_exactfu
- && (PL_fold[ender] != PL_fold_latin1[ender]
+
+ *(s++) = (char) ender;
+ }
+ else { /* Here, does participate in some fold */
+
+ /* if this is the first character in the node, change
+ * its type to folding. Otherwise, if this is the
+ * first folding character in the node, close up the
+ * existing node, so can start a new node with this
+ * one. */
+ if (! len) {
+ node_type = compute_EXACTish(pRExC_state);
+ }
+ else if (node_type == EXACT) {
+ p = oldp;
+ goto loopdone;
+ }
+
+ /* See if the character's fold differs between /d and
+ * /u. On non-ancient Unicode versions, this includes
+ * the multi-char fold SHARP S to 'ss' */
+
#if UNICODE_MAJOR_VERSION > 3 /* no multifolds in early Unicode */ \
|| (UNICODE_MAJOR_VERSION == 3 && ( UNICODE_DOT_VERSION > 0) \
|| UNICODE_DOT_DOT_VERSION > 0)
- || ( len > 0
- && isALPHA_FOLD_EQ(ender, 's')
- && isALPHA_FOLD_EQ(*(s-1), 's'))
+
+ if (UNLIKELY(ender == LATIN_SMALL_LETTER_SHARP_S)) {
+
+ /* See comments for join_exact() as to why we fold
+ * this non-UTF at compile time */
+ if (node_type == EXACTFU) {
+ *(s++) = 's';
+
+ /* Let the code below add in the extra 's' */
+ ender = 's';
+ added_len = 2;
+ }
+ else {
+ RExC_seen_unfolded_sharp_s = 1;
+ maybe_exactfu = FALSE;
+ }
+ }
+ else if ( len
+ && isALPHA_FOLD_EQ(ender, 's')
+ && isALPHA_FOLD_EQ(*(s-1), 's'))
+ {
+ maybe_exactfu = FALSE;
+ }
+ else
#endif
- )) {
+
+ if (PL_fold[ender] != PL_fold_latin1[ender]) {
maybe_exactfu = FALSE;
}
- }
/* Even when folding, we store just the input
* character, as we have an array that finds its fold
* quickly */
*(s++) = (char) ender;
+ }
}
- else { /* FOLD, and UTF (or sharp s) */
+ else { /* FOLD, and UTF */
/* Unlike the non-fold case, we do actually have to
* calculate the fold in pass 1. This is for two reasons,
* the folded length may be longer than the unfolded, and
* of a potential multi-char fold, and have to back off
* accordingly. */
- UV folded;
if (isASCII_uni(ender)) {
- folded = toFOLD(ender);
- *(s)++ = (U8) folded;
+
+ /* As above, we close up and start a new node if the
+ * previous characters don't match the fold/non-fold
+ * state of this one. And if this is the first
+ * character in the node, and it folds, we change the
+ * node away from being EXACT */
+ if (! IS_IN_SOME_FOLD_L1(ender)) {
+ if (len && node_type != EXACT) {
+ p = oldp;
+ goto loopdone;
+ }
+
+ *(s)++ = (U8) ender;
+ }
+ else { /* Is in a fold */
+
+ if (! len) {
+ node_type = compute_EXACTish(pRExC_state);
+ }
+ else if (node_type == EXACT) {
+ p = oldp;
+ goto loopdone;
+ }
+
+ *(s)++ = (U8) toFOLD(ender);
+ }
}
else { /* Not ASCII */
STRLEN foldlen;
- folded = _to_uni_fold_flags(
+ /* As above, we close up and start a new node if the
+ * previous characters don't match the fold/non-fold
+ * state of this one. And if this is the first
+ * character in the node, and it folds, we change the
+ * node away from being EXACT */
+ if (! _invlist_contains_cp(PL_utf8_foldable, ender)) {
+ if (len && node_type != EXACT) {
+ p = oldp;
+ goto loopdone;
+ }
+
+ s = (char *) uvchr_to_utf8((U8 *) s, ender);
+ added_len = UVCHR_SKIP(ender);
+ }
+ else {
+
+ if (! len) {
+ node_type = compute_EXACTish(pRExC_state);
+ }
+ else if (node_type == EXACT) {
+ p = oldp;
+ goto loopdone;
+ }
+
+ ender = _to_uni_fold_flags(
ender,
(U8 *) s,
&foldlen,
FOLD_FLAGS_FULL | ((ASCII_FOLD_RESTRICTED)
? FOLD_FLAGS_NOMIX_ASCII
: 0));
- s += foldlen;
- added_len = foldlen;
- }
- /* If this node only contains non-folding code points so
- * far, see if this new one is also non-folding */
- if (maybe_exact) {
- if (folded != ender) {
- maybe_exact = FALSE;
- }
- else {
- /* Here the fold is the original; we have to check
- * further to see if anything folds to it */
- if (_invlist_contains_cp(PL_utf8_foldable,
- ender))
- {
- maybe_exact = FALSE;
- }
+ s += foldlen;
+ added_len = foldlen;
}
}
- ender = folded;
}
len += added_len;
OP(ret) = NOTHING;
}
else {
- if (FOLD) {
- /* If 'maybe_exact' is still set here, means there are no
- * code points in the node that participate in folds;
- * similarly for 'maybe_exactfu' and code points that match
- * differently depending on UTF8ness of the target string
- * (for /u), or depending on locale for /l */
- if (maybe_exact) {
- OP(ret) = (LOC)
- ? EXACTL
- : EXACT;
+ OP(ret) = node_type;
+
+ /* If the node type is EXACT here, check to see if it
+ * should be EXACTL. */
+ if (node_type == EXACT) {
+ if (LOC) {
+ OP(ret) = EXACTL;
}
- else if (maybe_exactfu) {
- OP(ret) = (LOC)
- ? EXACTFLU8
- : EXACTFU;
+ }
+
+ if (FOLD) {
+ /* If 'maybe_exactfu' is set, then there are no code points
+ * that match differently depending on UTF8ness of the
+ * target string (for /u), or depending on locale for /l */
+ if (maybe_exactfu) {
+ if (node_type == EXACTF) {
+ OP(ret) = EXACTFU;
+ }
+ else if (node_type == EXACTFL) {
+ OP(ret) = EXACTFLU8;
+ }
}
}
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