This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
5.26.2 today
[perl5.git] / regexec.c
index 01c4b2f..1425508 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -175,38 +175,6 @@ static const char* const non_utf8_target_but_utf8_required
     locinput = (p);  \
     SET_nextchr
 
-
-#define LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist) STMT_START {   \
-        if (!swash_ptr) {                                                     \
-            U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;                       \
-            swash_ptr = _core_swash_init("utf8", property_name, &PL_sv_undef, \
-                                         1, 0, invlist, &flags);              \
-            assert(swash_ptr);                                                \
-        }                                                                     \
-    } STMT_END
-
-/* If in debug mode, we test that a known character properly matches */
-#ifdef DEBUGGING
-#   define LOAD_UTF8_CHARCLASS_DEBUG_TEST(swash_ptr,                          \
-                                          property_name,                      \
-                                          invlist,                            \
-                                          utf8_char_in_property)              \
-        LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist);               \
-        assert(swash_fetch(swash_ptr, (U8 *) utf8_char_in_property, TRUE));
-#else
-#   define LOAD_UTF8_CHARCLASS_DEBUG_TEST(swash_ptr,                          \
-                                          property_name,                      \
-                                          invlist,                            \
-                                          utf8_char_in_property)              \
-        LOAD_UTF8_CHARCLASS(swash_ptr, property_name, invlist)
-#endif
-
-#define LOAD_UTF8_CHARCLASS_ALNUM() LOAD_UTF8_CHARCLASS_DEBUG_TEST(           \
-                                        PL_utf8_swash_ptrs[_CC_WORDCHAR],     \
-                                        "",                                   \
-                                        PL_XPosix_ptrs[_CC_WORDCHAR],         \
-                                        LATIN_SMALL_LIGATURE_LONG_S_T_UTF8);
-
 #define PLACEHOLDER    /* Something for the preprocessor to grab onto */
 /* TODO: Combine JUMPABLE and HAS_TEXT to cache OP(rn) */
 
@@ -238,13 +206,13 @@ static const char* const non_utf8_target_but_utf8_required
 /* Currently these are only used when PL_regkind[OP(rn)] == EXACT so
    we don't need this definition.  XXX These are now out-of-sync*/
 #define IS_TEXT(rn)   ( OP(rn)==EXACT   || OP(rn)==REF   || OP(rn)==NREF   )
-#define IS_TEXTF(rn)  ( OP(rn)==EXACTFU || OP(rn)==EXACTFU_SS || OP(rn)==EXACTFA || OP(rn)==EXACTFA_NO_TRIE || OP(rn)==EXACTF || OP(rn)==REFF  || OP(rn)==NREFF )
+#define IS_TEXTF(rn)  ( OP(rn)==EXACTFU || OP(rn)==EXACTFU_SS || OP(rn)==EXACTFAA || OP(rn)==EXACTFAA_NO_TRIE || OP(rn)==EXACTF || OP(rn)==REFF  || OP(rn)==NREFF )
 #define IS_TEXTFL(rn) ( OP(rn)==EXACTFL || OP(rn)==REFFL || OP(rn)==NREFFL )
 
 #else
 /* ... so we use this as its faster. */
 #define IS_TEXT(rn)   ( OP(rn)==EXACT || OP(rn)==EXACTL )
-#define IS_TEXTFU(rn)  ( OP(rn)==EXACTFU || OP(rn)==EXACTFLU8 || OP(rn)==EXACTFU_SS || OP(rn) == EXACTFA || OP(rn) == EXACTFA_NO_TRIE)
+#define IS_TEXTFU(rn)  ( OP(rn)==EXACTFU || OP(rn)==EXACTFLU8 || OP(rn)==EXACTFU_SS || OP(rn) == EXACTFAA || OP(rn) == EXACTFAA_NO_TRIE)
 #define IS_TEXTF(rn)  ( OP(rn)==EXACTF  )
 #define IS_TEXTFL(rn) ( OP(rn)==EXACTFL )
 
@@ -500,7 +468,7 @@ Perl_isFOO_lc(pTHX_ const U8 classnum, const U8 character)
 #endif
 
 STATIC bool
-S_isFOO_utf8_lc(pTHX_ const U8 classnum, const U8* character)
+S_isFOO_utf8_lc(pTHX_ const U8 classnum, const U8* character, const U8* e)
 {
     /* Returns a boolean as to whether or not the (well-formed) UTF-8-encoded
      * 'character' is a member of the Posix character class given by 'classnum'
@@ -522,31 +490,16 @@ S_isFOO_utf8_lc(pTHX_ const U8 classnum, const U8* character)
                         EIGHT_BIT_UTF8_TO_NATIVE(*character, *(character + 1)));
     }
 
-    _CHECK_AND_OUTPUT_WIDE_LOCALE_UTF8_MSG(character, character + UTF8SKIP(character));
-
-    if (classnum < _FIRST_NON_SWASH_CC) {
-
-        /* Initialize the swash unless done already */
-        if (! PL_utf8_swash_ptrs[classnum]) {
-            U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-            PL_utf8_swash_ptrs[classnum] =
-                    _core_swash_init("utf8",
-                                     "",
-                                     &PL_sv_undef, 1, 0,
-                                     PL_XPosix_ptrs[classnum], &flags);
-        }
-
-        return cBOOL(swash_fetch(PL_utf8_swash_ptrs[classnum], (U8 *)
-                                 character,
-                                 TRUE /* is UTF */ ));
-    }
+    _CHECK_AND_OUTPUT_WIDE_LOCALE_UTF8_MSG(character, e);
 
     switch ((_char_class_number) classnum) {
         case _CC_ENUM_SPACE:     return is_XPERLSPACE_high(character);
         case _CC_ENUM_BLANK:     return is_HORIZWS_high(character);
         case _CC_ENUM_XDIGIT:    return is_XDIGIT_high(character);
         case _CC_ENUM_VERTSPACE: return is_VERTWS_high(character);
-        default:                 break;
+        default:
+            return _invlist_contains_cp(PL_XPosix_ptrs[classnum],
+                                        utf8_to_uvchr_buf(character, e, NULL));
     }
 
     return FALSE; /* Things like CNTRL are always below 256 */
@@ -587,17 +540,17 @@ S_find_next_ascii(char * s, const char * send, const bool utf8_target)
             PERL_UINTMAX_T complemented = ~ * (PERL_UINTMAX_T *) s;
             if (complemented & PERL_VARIANTS_WORD_MASK)  {
 
-#if   BYTEORDER == 0x1234 || BYTEORDER == 0x12345678    \
-   || BYTEORDER == 0x4321 || BYTEORDER == 0x87654321
+#  if   BYTEORDER == 0x1234 || BYTEORDER == 0x12345678    \
+     || BYTEORDER == 0x4321 || BYTEORDER == 0x87654321
 
                 s += _variant_byte_number(complemented);
                 return s;
 
-#else   /* If weird byte order, drop into next loop to do byte-at-a-time
+#  else   /* If weird byte order, drop into next loop to do byte-at-a-time
            checks. */
 
                 break;
-#endif
+#  endif
             }
 
             s += PERL_WORDSIZE;
@@ -676,8 +629,8 @@ S_find_next_non_ascii(char * s, const char * send, const bool utf8_target)
 
 }
 
-STATIC char *
-S_find_span_end(char * s, const char * send, const char span_byte)
+STATIC U8 *
+S_find_span_end(U8 * s, const U8 * send, const U8 span_byte)
 {
     /* Returns the position of the first byte in the sequence between 's' and
      * 'send-1' inclusive that isn't 'span_byte'; returns 'send' if none found.
@@ -714,8 +667,15 @@ S_find_span_end(char * s, const char * send, const char span_byte)
                 continue;
             }
 
-            /* Here, at least one byte in the word isn't 'span_byte'.  This xor
-             * leaves 1 bits only in those non-matching bytes */
+            /* Here, at least one byte in the word isn't 'span_byte'. */
+
+#ifdef EBCDIC
+
+            break;
+
+#else
+
+            /* This xor leaves 1 bits only in those non-matching bytes */
             span_word ^= * (PERL_UINTMAX_T *) s;
 
             /* Make sure the upper bit of each non-matching byte is set.  This
@@ -727,6 +687,8 @@ S_find_span_end(char * s, const char * send, const char span_byte)
             /* That reduces the problem to what this function solves */
             return s + _variant_byte_number(span_word);
 
+#endif
+
         } while (s + PERL_WORDSIZE <= send);
     }
 
@@ -741,6 +703,147 @@ S_find_span_end(char * s, const char * send, const char span_byte)
     return s;
 }
 
+STATIC U8 *
+S_find_next_masked(U8 * s, const U8 * send, const U8 byte, const U8 mask)
+{
+    /* Returns the position of the first byte in the sequence between 's'
+     * and 'send-1' inclusive that when ANDed with 'mask' yields 'byte';
+     * returns 'send' if none found.  It uses word-level operations instead of
+     * byte to speed up the process */
+
+    PERL_ARGS_ASSERT_FIND_NEXT_MASKED;
+
+    assert(send >= s);
+    assert((byte & mask) == byte);
+
+#ifndef EBCDIC
+
+    if ((STRLEN) (send - s) >= PERL_WORDSIZE
+                          + PERL_WORDSIZE * PERL_IS_SUBWORD_ADDR(s)
+                          - (PTR2nat(s) & PERL_WORD_BOUNDARY_MASK))
+    {
+        PERL_UINTMAX_T word_complemented, mask_word;
+
+        while (PTR2nat(s) & PERL_WORD_BOUNDARY_MASK) {
+            if (((*s) & mask) == byte) {
+                return s;
+            }
+            s++;
+        }
+
+        word_complemented = ~ (PERL_COUNT_MULTIPLIER * byte);
+        mask_word =            PERL_COUNT_MULTIPLIER * mask;
+
+        do {
+            PERL_UINTMAX_T masked = (* (PERL_UINTMAX_T *) s) & mask_word;
+
+            /* If 'masked' contains 'byte' within it, anding with the
+             * complement will leave those 8 bits 0 */
+            masked &= word_complemented;
+
+            /* This causes the most significant bit to be set to 1 for any
+             * bytes in the word that aren't completely 0 */
+            masked |= masked << 1;
+            masked |= masked << 2;
+            masked |= masked << 4;
+
+            /* The msbits are the same as what marks a byte as variant, so we
+             * can use this mask.  If all msbits are 1, the word doesn't
+             * contain 'byte' */
+            if ((masked & PERL_VARIANTS_WORD_MASK) == PERL_VARIANTS_WORD_MASK) {
+                s += PERL_WORDSIZE;
+                continue;
+            }
+
+            /* Here, the msbit of bytes in the word that aren't 'byte' are 1,
+             * and any that are, are 0.  Complement and re-AND to swap that */
+            masked = ~ masked;
+            masked &= PERL_VARIANTS_WORD_MASK;
+
+            /* This reduces the problem to that solved by this function */
+            s += _variant_byte_number(masked);
+            return s;
+
+        } while (s + PERL_WORDSIZE <= send);
+    }
+
+#endif
+
+    while (s < send) {
+        if (((*s) & mask) == byte) {
+            return s;
+        }
+        s++;
+    }
+
+    return s;
+}
+
+STATIC U8 *
+S_find_span_end_mask(U8 * s, const U8 * send, const U8 span_byte, const U8 mask)
+{
+    /* Returns the position of the first byte in the sequence between 's' and
+     * 'send-1' inclusive that when ANDed with 'mask' isn't 'span_byte'.
+     * 'span_byte' should have been ANDed with 'mask' in the call of this
+     * function.  Returns 'send' if none found.  Works like find_span_end(),
+     * except for the AND */
+
+    PERL_ARGS_ASSERT_FIND_SPAN_END_MASK;
+
+    assert(send >= s);
+    assert((span_byte & mask) == span_byte);
+
+    if ((STRLEN) (send - s) >= PERL_WORDSIZE
+                          + PERL_WORDSIZE * PERL_IS_SUBWORD_ADDR(s)
+                          - (PTR2nat(s) & PERL_WORD_BOUNDARY_MASK))
+    {
+        PERL_UINTMAX_T span_word, mask_word;
+
+        while (PTR2nat(s) & PERL_WORD_BOUNDARY_MASK) {
+            if (((*s) & mask) != span_byte) {
+                return s;
+            }
+            s++;
+        }
+
+        span_word = PERL_COUNT_MULTIPLIER * span_byte;
+        mask_word = PERL_COUNT_MULTIPLIER * mask;
+
+        do {
+            PERL_UINTMAX_T masked = (* (PERL_UINTMAX_T *) s) & mask_word;
+
+            if (masked == span_word) {
+                s += PERL_WORDSIZE;
+                continue;
+            }
+
+#ifdef EBCDIC
+
+            break;
+
+#else
+
+            masked ^= span_word;
+            masked |= masked << 1;
+            masked |= masked << 2;
+            masked |= masked << 4;
+            return s + _variant_byte_number(masked);
+
+#endif
+
+        } while (s + PERL_WORDSIZE <= send);
+    }
+
+    while (s < send) {
+        if (((*s) & mask) != span_byte) {
+            return s;
+        }
+        s++;
+    }
+
+    return s;
+}
+
 /*
  * pregexec and friends
  */
@@ -1109,7 +1212,7 @@ Perl_re_intuit_start(pTHX_
 
             if (check_len > targ_len) {
                 DEBUG_EXECUTE_r(Perl_re_printf( aTHX_
-                             "Anchored string too short...\n"));
+                             "Target string too short to match required substring...\n"));
                 goto fail_finish;
             }
 
@@ -1124,6 +1227,8 @@ Perl_re_intuit_start(pTHX_
                                 end_point - check_len
                             )
                             + check_len;
+                if (end_point < start_point)
+                    goto fail_finish;
             }
         }
 
@@ -1681,7 +1786,7 @@ Perl_re_intuit_start(pTHX_
                                  ? (utf8_target ? trie_utf8 : trie_plain)           \
                                  : (scan->flags == EXACTL)                          \
                                     ? (utf8_target ? trie_utf8l : trie_plain)       \
-                                    : (scan->flags == EXACTFA                     \
+                                    : (scan->flags == EXACTFAA)                     \
                                       ? (utf8_target                                \
                                          ? trie_utf8_exactfa_fold                   \
                                          : trie_latin_utf8_exactfa_fold)            \
@@ -1769,17 +1874,6 @@ STMT_START {
     dump_exec_pos(li,s,(reginfo->strend),(reginfo->strbeg), \
                 startpos, doutf8, depth)
 
-#define REXEC_FBC_EXACTISH_SCAN(COND)                     \
-STMT_START {                                              \
-    while (s <= e) {                                      \
-       if ( (COND)                                       \
-            && (ln == 1 || folder(s, pat_string, ln))    \
-            && (reginfo->intuit || regtry(reginfo, &s)) )\
-           goto got_it;                                  \
-       s++;                                              \
-    }                                                     \
-} STMT_END
-
 #define REXEC_FBC_SCAN(UTF8, CODE)                          \
     STMT_START {                                            \
         while (s < strend) {                                \
@@ -1831,7 +1925,7 @@ STMT_START {                                              \
  * there is no such occurrence. */
 #define REXEC_FBC_FIND_NEXT_SCAN(UTF8, f)                   \
     while (s < strend) {                                    \
-        s = f;                                              \
+        s = (f);                                            \
         if (s >= strend) {                                  \
             break;                                          \
         }                                                   \
@@ -1903,7 +1997,6 @@ STMT_START {                                              \
                                                        0, UTF8_ALLOW_DEFAULT); \
     }                                                                          \
     tmp = TEST_UV(tmp);                                                        \
-    LOAD_UTF8_CHARCLASS_ALNUM();                                               \
     REXEC_FBC_SCAN(1,  /* 1=>is-utf8; advances s while s < strend */           \
         if (tmp == ! (TEST_UTF8((U8 *) s, (U8 *) reginfo->strend))) {          \
             tmp = !tmp;                                                        \
@@ -2127,10 +2220,17 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
         }
         break;
 
-    case EXACTFA_NO_TRIE:   /* This node only generated for non-utf8 patterns */
+    case ANYOFM:    /* ARG() is the base byte; FLAGS() the mask byte */
+        /* UTF-8ness doesn't matter, so use 0 */
+        REXEC_FBC_FIND_NEXT_SCAN(0,
+         (char *) find_next_masked((U8 *) s, (U8 *) strend,
+                                   (U8) ARG(c), FLAGS(c)));
+        break;
+
+    case EXACTFAA_NO_TRIE: /* This node only generated for non-utf8 patterns */
         assert(! is_utf8_pat);
        /* FALLTHROUGH */
-    case EXACTFA:
+    case EXACTFAA:
         if (is_utf8_pat || utf8_target) {
             utf8_fold_flags = FOLDEQ_UTF8_NOMIX_ASCII;
             goto do_exactf_utf8;
@@ -2213,10 +2313,57 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
         c1 = *pat_string;
         c2 = fold_array[c1];
         if (c1 == c2) { /* If char and fold are the same */
-            REXEC_FBC_EXACTISH_SCAN(*(U8*)s == c1);
+            while (s <= e) {
+                s = (char *) memchr(s, c1, e + 1 - s);
+                if (s == NULL) {
+                    break;
+                }
+
+                /* Check that the rest of the node matches */
+                if (   (ln == 1 || folder(s + 1, pat_string + 1, ln - 1))
+                    && (reginfo->intuit || regtry(reginfo, &s)) )
+                {
+                    goto got_it;
+                }
+                s++;
+            }
         }
         else {
-            REXEC_FBC_EXACTISH_SCAN(*(U8*)s == c1 || *(U8*)s == c2);
+            U8 bits_differing = c1 ^ c2;
+
+            /* If the folds differ in one bit position only, we can mask to
+             * match either of them, and can use this faster find method.  Both
+             * ASCII and EBCDIC tend to have their case folds differ in only
+             * one position, so this is very likely */
+            if (LIKELY(PL_bitcount[bits_differing] == 1)) {
+                bits_differing = ~ bits_differing;
+                while (s <= e) {
+                    s = (char *) find_next_masked((U8 *) s, (U8 *) e + 1,
+                                        (c1 & bits_differing), bits_differing);
+                    if (s > e) {
+                        break;
+                    }
+
+                    if (   (ln == 1 || folder(s + 1, pat_string + 1, ln - 1))
+                        && (reginfo->intuit || regtry(reginfo, &s)) )
+                    {
+                        goto got_it;
+                    }
+                    s++;
+                }
+            }
+            else {  /* Otherwise, stuck with looking byte-at-a-time.  This
+                       should actually happen only in EXACTFL nodes */
+                while (s <= e) {
+                    if (    (*(U8*)s == c1 || *(U8*)s == c2)
+                        && (ln == 1 || folder(s + 1, pat_string + 1, ln - 1))
+                        && (reginfo->intuit || regtry(reginfo, &s)) )
+                    {
+                        goto got_it;
+                    }
+                    s++;
+                }
+            }
         }
         break;
 
@@ -2617,7 +2764,7 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
 
     case POSIXL:
         _CHECK_AND_WARN_PROBLEMATIC_LOCALE;
-        REXEC_FBC_CSCAN(to_complement ^ cBOOL(isFOO_utf8_lc(FLAGS(c), (U8 *) s)),
+        REXEC_FBC_CSCAN(to_complement ^ cBOOL(isFOO_utf8_lc(FLAGS(c), (U8 *) s, (U8 *) strend)),
                         to_complement ^ cBOOL(isFOO_lc(FLAGS(c), *s)));
         break;
 
@@ -2672,29 +2819,15 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
 
           posix_utf8:
             classnum = (_char_class_number) FLAGS(c);
-            if (classnum < _FIRST_NON_SWASH_CC) {
-                while (s < strend) {
-
-                    /* We avoid loading in the swash as long as possible, but
-                     * should we have to, we jump to a separate loop.  This
-                     * extra 'if' statement is what keeps this code from being
-                     * just a call to REXEC_FBC_CLASS_SCAN() */
-                    if (UTF8_IS_ABOVE_LATIN1(*s)) {
-                        goto found_above_latin1;
-                    }
-
-                    REXEC_FBC_CLASS_SCAN_GUTS(1, (UTF8_IS_INVARIANT(*s)
-                         && to_complement ^ cBOOL(_generic_isCC((U8) *s,
-                                                                classnum)))
-                        || (   UTF8_IS_NEXT_CHAR_DOWNGRADEABLE(s, strend)
-                            && to_complement ^ cBOOL(
-                                _generic_isCC(EIGHT_BIT_UTF8_TO_NATIVE(*s,
-                                                                      *(s + 1)),
-                                              classnum))));
-                }
-            }
-            else switch (classnum) {    /* These classes are implemented as
-                                           macros */
+            switch (classnum) {
+                default:
+                    REXEC_FBC_CLASS_SCAN(1, /* 1=>is-utf8 */
+                        to_complement ^ cBOOL(_invlist_contains_cp(
+                                              PL_XPosix_ptrs[classnum],
+                                              utf8_to_uvchr_buf((U8 *) s,
+                                                                (U8 *) strend,
+                                                                NULL))));
+                    break;
                 case _CC_ENUM_SPACE:
                     REXEC_FBC_CLASS_SCAN(1, /* 1=>is-utf8 */
                         to_complement ^ cBOOL(isSPACE_utf8_safe(s, strend)));
@@ -2719,37 +2852,10 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
                     REXEC_FBC_CLASS_SCAN(1,
                         to_complement ^ cBOOL(isCNTRL_utf8_safe(s, strend)));
                     break;
-
-                default:
-                    Perl_croak(aTHX_ "panic: find_byclass() node %d='%s' has an unexpected character class '%d'", OP(c), PL_reg_name[OP(c)], classnum);
-                    NOT_REACHED; /* NOTREACHED */
             }
         }
         break;
 
-      found_above_latin1:   /* Here we have to load a swash to get the result
-                               for the current code point */
-        if (! PL_utf8_swash_ptrs[classnum]) {
-            U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-            PL_utf8_swash_ptrs[classnum] =
-                    _core_swash_init("utf8",
-                                     "",
-                                     &PL_sv_undef, 1, 0,
-                                     PL_XPosix_ptrs[classnum], &flags);
-        }
-
-        /* This is a copy of the loop above for swash classes, though using the
-         * FBC macro instead of being expanded out.  Since we've loaded the
-         * swash, we don't have to check for that each time through the loop */
-        REXEC_FBC_CLASS_SCAN(1, /* 1=>is-utf8 */
-                to_complement ^ cBOOL(_generic_utf8_safe(
-                                      classnum,
-                                      s,
-                                      strend,
-                                      swash_fetch(PL_utf8_swash_ptrs[classnum],
-                                                  (U8 *) s, TRUE))));
-        break;
-
     case AHOCORASICKC:
     case AHOCORASICK:
         {
@@ -4405,70 +4511,40 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
         else { /* an EXACTFish node which doesn't begin with a multi-char fold */
             c1 = is_utf8_pat ? valid_utf8_to_uvchr(pat, NULL) : *pat;
             if (c1 > 255) {
-                /* Load the folds hash, if not already done */
-                SV** listp;
-                if (! PL_utf8_foldclosures) {
-                    _load_PL_utf8_foldclosures();
+                const unsigned int * remaining_folds_to_list;
+                unsigned int first_folds_to;
+
+                /* Look up what code points (besides c1) fold to c1;  e.g.,
+                 * [ 'K', KELVIN_SIGN ] both fold to 'k'. */
+                Size_t folds_to_count = _inverse_folds(c1,
+                                                     &first_folds_to,
+                                                     &remaining_folds_to_list);
+                if (folds_to_count == 0) {
+                    c2 = c1;    /* there is only a single character that could
+                                   match */
                 }
-
-                /* The fold closures data structure is a hash with the keys
-                 * being the UTF-8 of every character that is folded to, like
-                 * 'k', and the values each an array of all code points that
-                 * fold to its key.  e.g. [ 'k', 'K', KELVIN_SIGN ].
-                 * Multi-character folds are not included */
-                if ((! (listp = hv_fetch(PL_utf8_foldclosures,
-                                        (char *) pat,
-                                        UTF8SKIP(pat),
-                                        FALSE))))
-                {
-                    /* Not found in the hash, therefore there are no folds
-                    * containing it, so there is only a single character that
-                    * could match */
-                    c2 = c1;
+                else if (folds_to_count != 1) {
+                    /* If there aren't exactly two folds to this (itself and
+                     * another), it is outside the scope of this function */
+                    use_chrtest_void = TRUE;
                 }
-                else {  /* Does participate in folds */
-                    AV* list = (AV*) *listp;
-                    if (av_tindex_skip_len_mg(list) != 1) {
-
-                        /* If there aren't exactly two folds to this, it is
-                         * outside the scope of this function */
-                        use_chrtest_void = TRUE;
-                    }
-                    else {  /* There are two.  Get them */
-                        SV** c_p = av_fetch(list, 0, FALSE);
-                        if (c_p == NULL) {
-                            Perl_croak(aTHX_ "panic: invalid PL_utf8_foldclosures structure");
-                        }
-                        c1 = SvUV(*c_p);
-
-                        c_p = av_fetch(list, 1, FALSE);
-                        if (c_p == NULL) {
-                            Perl_croak(aTHX_ "panic: invalid PL_utf8_foldclosures structure");
-                        }
-                        c2 = SvUV(*c_p);
-
-                        /* Folds that cross the 255/256 boundary are forbidden
-                         * if EXACTFL (and isnt a UTF8 locale), or EXACTFA and
-                         * one is ASCIII.  Since the pattern character is above
-                         * 255, and its only other match is below 256, the only
-                         * legal match will be to itself.  We have thrown away
-                         * the original, so have to compute which is the one
-                         * above 255. */
-                        if ((c1 < 256) != (c2 < 256)) {
-                            if ((OP(text_node) == EXACTFL
-                                 && ! IN_UTF8_CTYPE_LOCALE)
-                                || ((OP(text_node) == EXACTFA
-                                    || OP(text_node) == EXACTFA_NO_TRIE)
-                                    && (isASCII(c1) || isASCII(c2))))
-                            {
-                                if (c1 < 256) {
-                                    c1 = c2;
-                                }
-                                else {
-                                    c2 = c1;
-                                }
-                            }
-                        }
+                else {  /* There are two.  We already have one, get the other */
+                    c2 = first_folds_to;
+
+                    /* Folds that cross the 255/256 boundary are forbidden if
+                     * EXACTFL (and isnt a UTF8 locale), or EXACTFAA and one is
+                     * ASCIII.  The only other match to c1 is c2, and since c1
+                     * is above 255, c2 better be as well under these
+                     * circumstances.  If it isn't, it means the only legal
+                     * match of c1 is itself. */
+                    if (    c2 < 256
+                        && (   (   OP(text_node) == EXACTFL
+                                && ! IN_UTF8_CTYPE_LOCALE)
+                            || ((     OP(text_node) == EXACTFAA
+                                   || OP(text_node) == EXACTFAA_NO_TRIE)
+                                && (isASCII(c1) || isASCII(c2)))))
+                    {
+                        c2 = c1;
                     }
                 }
             }
@@ -4476,8 +4552,8 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
                 if (utf8_target
                     && HAS_NONLATIN1_FOLD_CLOSURE(c1)
                     && ( ! (OP(text_node) == EXACTFL && ! IN_UTF8_CTYPE_LOCALE))
-                    && ((OP(text_node) != EXACTFA
-                        && OP(text_node) != EXACTFA_NO_TRIE)
+                    && ((OP(text_node) != EXACTFAA
+                        && OP(text_node) != EXACTFAA_NO_TRIE)
                         || ! isASCII(c1)))
             {
                 /* Here, there could be something above Latin1 in the target
@@ -4509,12 +4585,12 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
                         }
                         /* FALLTHROUGH */
                         /* /u rules for all these.  This happens to work for
-                        * EXACTFA as nothing in Latin1 folds to ASCII */
-                    case EXACTFA_NO_TRIE:   /* This node only generated for
-                                            non-utf8 patterns */
+                        * EXACTFAA as nothing in Latin1 folds to ASCII */
+                    case EXACTFAA_NO_TRIE:   /* This node only generated for
+                                                non-utf8 patterns */
                         assert(! is_utf8_pat);
                         /* FALLTHROUGH */
-                    case EXACTFA:
+                    case EXACTFAA:
                     case EXACTFU_SS:
                     case EXACTFU:
                         c2 = PL_fold_latin1[c1];
@@ -5774,7 +5850,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
              */
             if(!NEXTCHR_IS_EOS && !ANYOF_BITMAP_TEST(scan, nextchr)) {
                 DEBUG_EXECUTE_r(
-                    Perl_re_exec_indentf( aTHX_  "%sfailed to match trie start class...%s\n",
+                    Perl_re_exec_indentf( aTHX_  "%sTRIE: failed to match trie start class...%s\n",
                               depth, PL_colors[4], PL_colors[5])
                 );
                 sayNO_SILENT;
@@ -5839,7 +5915,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                 if (scan->flags == EXACTL || scan->flags == EXACTFLU8) {
                     _CHECK_AND_WARN_PROBLEMATIC_LOCALE;
                     if (utf8_target
-                        && nextchr >= 0 /* guard against negative EOS value in nextchr */
+                        && ! NEXTCHR_IS_EOS
                         && UTF8_IS_ABOVE_LATIN1(nextchr)
                         && scan->flags == EXACTL)
                     {
@@ -5855,14 +5931,14 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                 {
                    if (trie->states[ state ].wordnum) {
                         DEBUG_EXECUTE_r(
-                            Perl_re_exec_indentf( aTHX_  "%smatched empty string...%s\n",
+                            Perl_re_exec_indentf( aTHX_  "%sTRIE: matched empty string...%s\n",
                                           depth, PL_colors[4], PL_colors[5])
                         );
                        if (!trie->jump)
                            break;
                    } else {
                        DEBUG_EXECUTE_r(
-                            Perl_re_exec_indentf( aTHX_  "%sfailed to match trie start class...%s\n",
+                            Perl_re_exec_indentf( aTHX_  "%sTRIE: failed to match trie start class...%s\n",
                                           depth, PL_colors[4], PL_colors[5])
                         );
                        sayNO_SILENT;
@@ -5918,7 +5994,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                                 DUMP_EXEC_POS( (char *)uc, scan, utf8_target, depth );
                                 /* HERE */
                                 PerlIO_printf( Perl_debug_log,
-                                    "%*s%sState: %4" UVxf " Accepted: %c ",
+                                    "%*s%sTRIE: State: %4" UVxf " Accepted: %c ",
                                     INDENT_CHARS(depth), "", PL_colors[4],
                                    (UV)state, (accepted ? 'Y' : 'N'));
                    });
@@ -5952,7 +6028,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                    }
                    DEBUG_TRIE_EXECUTE_r(
                         Perl_re_printf( aTHX_
-                           "Charid:%3x CP:%4" UVxf " After State: %4" UVxf "%s\n",
+                           "TRIE: Charid:%3x CP:%4" UVxf " After State: %4" UVxf "%s\n",
                            charid, uvc, (UV)state, PL_colors[5] );
                    );
                }
@@ -5971,7 +6047,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                }
 
                DEBUG_EXECUTE_r(
-                    Perl_re_exec_indentf( aTHX_  "%sgot %" IVdf " possible matches%s\n",
+                    Perl_re_exec_indentf( aTHX_  "%sTRIE: got %" IVdf " possible matches%s\n",
                         depth,
                        PL_colors[4], (IV)ST.accepted, PL_colors[5] );
                );
@@ -6104,7 +6180,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                         ? av_fetch(trie_words, ST.nextword - 1, 0) : NULL;
                SV *sv= tmp ? sv_newmortal() : NULL;
 
-                Perl_re_exec_indentf( aTHX_  "%sonly one match left, short-circuiting: #%d <%s>%s\n",
+                Perl_re_exec_indentf( aTHX_  "%sTRIE: only one match left, short-circuiting: #%d <%s>%s\n",
                     depth, PL_colors[4],
                    ST.nextword,
                    tmp ? pv_pretty(sv, SvPV_nolen_const(*tmp), SvCUR(*tmp), 0,
@@ -6245,11 +6321,11 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
            fold_utf8_flags = is_utf8_pat ? FOLDEQ_S1_ALREADY_FOLDED : 0;
            goto do_exactf;
 
-        case EXACTFA_NO_TRIE:   /* This node only generated for non-utf8
+        case EXACTFAA_NO_TRIE:   /* This node only generated for non-utf8
                                    patterns */
             assert(! is_utf8_pat);
             /* FALLTHROUGH */
-       case EXACTFA:            /*  /abc/iaa     */
+       case EXACTFAA:            /*  /abc/iaa     */
            folder = foldEQ_latin1;
            fold_array = PL_fold_latin1;
            fold_utf8_flags = FOLDEQ_UTF8_NOMIX_ASCII;
@@ -6602,6 +6678,13 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
            }
            break;
 
+        case ANYOFM:
+            if (NEXTCHR_IS_EOS || (UCHARAT(locinput) & FLAGS(scan)) != ARG(scan)) {
+                sayNO;
+            }
+            locinput++;
+            break;
+
         case ASCII:
             if (NEXTCHR_IS_EOS || ! isASCII(UCHARAT(locinput))) {
                 sayNO;
@@ -6742,62 +6825,52 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
             else {  /* Handle above Latin-1 code points */
               utf8_posix_above_latin1:
                 classnum = (_char_class_number) FLAGS(scan);
-                if (classnum < _FIRST_NON_SWASH_CC) {
-
-                    /* Here, uses a swash to find such code points.  Load if if
-                     * not done already */
-                    if (! PL_utf8_swash_ptrs[classnum]) {
-                        U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-                        PL_utf8_swash_ptrs[classnum]
-                                = _core_swash_init("utf8",
-                                        "",
-                                        &PL_sv_undef, 1, 0,
-                                        PL_XPosix_ptrs[classnum], &flags);
-                    }
-                    if (! (to_complement
-                           ^ cBOOL(swash_fetch(PL_utf8_swash_ptrs[classnum],
-                                               (U8 *) locinput, TRUE))))
-                    {
-                        sayNO;
-                    }
-                }
-                else {  /* Here, uses macros to find above Latin-1 code points */
-                    switch (classnum) {
-                        case _CC_ENUM_SPACE:
-                            if (! (to_complement
-                                        ^ cBOOL(is_XPERLSPACE_high(locinput))))
-                            {
-                                sayNO;
-                            }
-                            break;
-                        case _CC_ENUM_BLANK:
-                            if (! (to_complement
-                                            ^ cBOOL(is_HORIZWS_high(locinput))))
-                            {
-                                sayNO;
-                            }
-                            break;
-                        case _CC_ENUM_XDIGIT:
-                            if (! (to_complement
-                                            ^ cBOOL(is_XDIGIT_high(locinput))))
-                            {
-                                sayNO;
-                            }
-                            break;
-                        case _CC_ENUM_VERTSPACE:
-                            if (! (to_complement
-                                            ^ cBOOL(is_VERTWS_high(locinput))))
-                            {
-                                sayNO;
-                            }
-                            break;
-                        default:    /* The rest, e.g. [:cntrl:], can't match
-                                       above Latin1 */
-                            if (! to_complement) {
-                                sayNO;
-                            }
-                            break;
-                    }
+                switch (classnum) {
+                    default:
+                        if (! (to_complement
+                           ^ cBOOL(_invlist_contains_cp(
+                                      PL_XPosix_ptrs[classnum],
+                                      utf8_to_uvchr_buf((U8 *) locinput,
+                                                        (U8 *) reginfo->strend,
+                                                        NULL)))))
+                        {
+                            sayNO;
+                        }
+                        break;
+                    case _CC_ENUM_SPACE:
+                        if (! (to_complement
+                                    ^ cBOOL(is_XPERLSPACE_high(locinput))))
+                        {
+                            sayNO;
+                        }
+                        break;
+                    case _CC_ENUM_BLANK:
+                        if (! (to_complement
+                                        ^ cBOOL(is_HORIZWS_high(locinput))))
+                        {
+                            sayNO;
+                        }
+                        break;
+                    case _CC_ENUM_XDIGIT:
+                        if (! (to_complement
+                                        ^ cBOOL(is_XDIGIT_high(locinput))))
+                        {
+                            sayNO;
+                        }
+                        break;
+                    case _CC_ENUM_VERTSPACE:
+                        if (! (to_complement
+                                        ^ cBOOL(is_VERTWS_high(locinput))))
+                        {
+                            sayNO;
+                        }
+                        break;
+                    case _CC_ENUM_CNTRL:    /* These can't match above Latin1 */
+                    case _CC_ENUM_ASCII:
+                        if (! to_complement) {
+                            sayNO;
+                        }
+                        break;
                 }
                 locinput += UTF8SKIP(locinput);
             }
@@ -7339,7 +7412,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                rei = RXi_GET(re);
                 DEBUG_EXECUTE_r(
                     debug_start_match(re_sv, utf8_target, locinput,
-                                    reginfo->strend, "Matching embedded");
+                                    reginfo->strend, "EVAL/GOSUB: Matching embedded");
                );              
                startpoint = rei->program + 1;
                 EVAL_CLOSE_PAREN_CLEAR(st); /* ST.close_paren = 0;
@@ -7469,7 +7542,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
            if (n > maxopenparen)
                maxopenparen = n;
             DEBUG_BUFFERS_r(Perl_re_exec_indentf( aTHX_
-               "rex=0x%" UVxf " offs=0x%" UVxf ": \\%" UVuf ": set %" IVdf " tmp; maxopenparen=%" UVuf "\n",
+               "OPEN: rex=0x%" UVxf " offs=0x%" UVxf ": \\%" UVuf ": set %" IVdf " tmp; maxopenparen=%" UVuf "\n",
                 depth,
                PTR2UV(rex),
                PTR2UV(rex->offs),
@@ -7489,7 +7562,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
     rex->offs[n].start = rex->offs[n].start_tmp;                           \
     rex->offs[n].end = locinput - reginfo->strbeg;                         \
     DEBUG_BUFFERS_r(Perl_re_exec_indentf( aTHX_                            \
-        "rex=0x%" UVxf " offs=0x%" UVxf ": \\%" UVuf ": set %" IVdf "..%" IVdf "\n", \
+        "CLOSE: rex=0x%" UVxf " offs=0x%" UVxf ": \\%" UVuf ": set %" IVdf "..%" IVdf "\n", \
         depth,                                                             \
         PTR2UV(rex),                                                       \
         PTR2UV(rex->offs),                                                 \
@@ -7730,7 +7803,7 @@ NULL
            ST.cache_mask = 0;
            
 
-            DEBUG_EXECUTE_r( Perl_re_exec_indentf( aTHX_  "whilem: matched %ld out of %d..%d\n",
+            DEBUG_EXECUTE_r( Perl_re_exec_indentf( aTHX_  "WHILEM: matched %ld out of %d..%d\n",
                   depth, (long)n, min, max)
            );
 
@@ -7748,7 +7821,7 @@ NULL
            /* If degenerate A matches "", assume A done. */
 
            if (locinput == cur_curlyx->u.curlyx.lastloc) {
-                DEBUG_EXECUTE_r( Perl_re_exec_indentf( aTHX_  "whilem: empty match detected, trying continuation...\n",
+                DEBUG_EXECUTE_r( Perl_re_exec_indentf( aTHX_  "WHILEM: empty match detected, trying continuation...\n",
                    depth)
                );
                goto do_whilem_B_max;
@@ -7816,7 +7889,7 @@ NULL
                        Newxz(aux->poscache, size, char);
                    }
                     DEBUG_EXECUTE_r( Perl_re_printf( aTHX_
-      "%swhilem: Detected a super-linear match, switching on caching%s...\n",
+      "%sWHILEM: Detected a super-linear match, switching on caching%s...\n",
                              PL_colors[4], PL_colors[5])
                    );
                }
@@ -7832,7 +7905,7 @@ NULL
                    mask    = 1 << (offset % 8);
                    offset /= 8;
                    if (reginfo->info_aux->poscache[offset] & mask) {
-                        DEBUG_EXECUTE_r( Perl_re_exec_indentf( aTHX_  "whilem: (cache) already tried at this position...\n",
+                        DEBUG_EXECUTE_r( Perl_re_exec_indentf( aTHX_  "WHILEM: (cache) already tried at this position...\n",
                             depth)
                        );
                         cur_curlyx->u.curlyx.count--;
@@ -7893,7 +7966,7 @@ NULL
        case WHILEM_A_max_fail: /* just failed to match A in a maximal match */
            REGCP_UNWIND(ST.lastcp);
             regcppop(rex, &maxopenparen); /* Restore some previous $<digit>s? */
-            DEBUG_EXECUTE_r(Perl_re_exec_indentf( aTHX_  "whilem: failed, trying continuation...\n",
+            DEBUG_EXECUTE_r(Perl_re_exec_indentf( aTHX_  "WHILEM: failed, trying continuation...\n",
                 depth)
            );
          do_whilem_B_max:
@@ -7934,7 +8007,7 @@ NULL
                CACHEsayNO;
            }
 
-            DEBUG_EXECUTE_r(Perl_re_exec_indentf( aTHX_  "trying longer...\n", depth)
+            DEBUG_EXECUTE_r(Perl_re_exec_indentf( aTHX_  "WHILEM: B min fail: trying longer...\n", depth)
            );
            /* Try grabbing another A and see if it helps. */
            cur_curlyx->u.curlyx.lastloc = locinput;
@@ -8565,7 +8638,7 @@ NULL
                st->u.eval.prev_eval = cur_eval;
                 cur_eval = CUR_EVAL.prev_eval;
                DEBUG_EXECUTE_r(
-                    Perl_re_exec_indentf( aTHX_  "EVAL trying tail ... (cur_eval=%p)\n",
+                    Perl_re_exec_indentf( aTHX_  "END: EVAL trying tail ... (cur_eval=%p)\n",
                                       depth, cur_eval););
                 if ( nochange_depth )
                    nochange_depth--;
@@ -8578,7 +8651,7 @@ NULL
 
            if (locinput < reginfo->till) {
                 DEBUG_EXECUTE_r(Perl_re_printf( aTHX_
-                                      "%sMatch possible, but length=%ld is smaller than requested=%ld, failing!%s\n",
+                                      "%sEND: Match possible, but length=%ld is smaller than requested=%ld, failing!%s\n",
                                      PL_colors[4],
                                      (long)(locinput - startpos),
                                      (long)(reginfo->till - startpos),
@@ -8590,7 +8663,7 @@ NULL
 
        case SUCCEED: /* successful SUSPEND/UNLESSM/IFMATCH/CURLYM */
            DEBUG_EXECUTE_r(
-            Perl_re_exec_indentf( aTHX_  "%ssubpattern success...%s\n",
+            Perl_re_exec_indentf( aTHX_  "%sSUCCEED: subpattern success...%s\n",
                 depth, PL_colors[4], PL_colors[5]));
            sayYES;                     /* Success! */
 
@@ -8725,7 +8798,7 @@ NULL
                 sv_commit = ST.mark_name;
 
                 DEBUG_EXECUTE_r({
-                        Perl_re_exec_indentf( aTHX_  "%ssetting cutpoint to mark:%" SVf "...%s\n",
+                        Perl_re_exec_indentf( aTHX_  "%sMARKPOINT: next fail: setting cutpoint to mark:%" SVf "...%s\n",
                             depth,
                            PL_colors[4], SVfARG(sv_commit), PL_colors[5]);
                });
@@ -9105,7 +9178,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
                  * since here, to match at all, 1 char == 1 byte */
                 loceol = scan + max;
             }
-            scan = find_span_end(scan, loceol, (U8) c);
+            scan = (char *) find_span_end((U8 *) scan, (U8 *) loceol, (U8) c);
        }
        else if (reginfo->is_utf8_pat) {
             if (utf8_target) {
@@ -9127,7 +9200,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
                 /* Target isn't utf8; convert the character in the UTF-8
                  * pattern to non-UTF8, and do a simple find */
                 c = EIGHT_BIT_UTF8_TO_NATIVE(c, *(STRING(p) + 1));
-                scan = find_span_end(scan, loceol, (U8) c);
+                scan = (char *) find_span_end((U8 *) scan, (U8 *) loceol, (U8) c);
             } /* else pattern char is above Latin1, can't possibly match the
                  non-UTF-8 target */
         }
@@ -9151,10 +9224,10 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
        }
        break;
 
-    case EXACTFA_NO_TRIE:   /* This node only generated for non-utf8 patterns */
+    case EXACTFAA_NO_TRIE: /* This node only generated for non-utf8 patterns */
         assert(! reginfo->is_utf8_pat);
         /* FALLTHROUGH */
-    case EXACTFA:
+    case EXACTFAA:
         utf8_flags = FOLDEQ_UTF8_NOMIX_ASCII;
        goto do_exactf;
 
@@ -9225,7 +9298,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
                 }
             }
             else if (c1 == c2) {
-                scan = find_span_end(scan, loceol, c1);
+                scan = (char *) find_span_end((U8 *) scan, (U8 *) loceol, (U8) c1);
             }
             else {
                 /* See comments in regmatch() CURLY_B_min_known_fail.  We avoid
@@ -9234,14 +9307,12 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
                 U8 c1_c2_bits_differing = c1 ^ c2;
 
                 if (isPOWER_OF_2(c1_c2_bits_differing)) {
-                    U8 c1_masked = c1 & ~ c1_c2_bits_differing;
                     U8 c1_c2_mask = ~ c1_c2_bits_differing;
 
-                    while (   scan < loceol
-                           && (UCHARAT(scan) & c1_c2_mask) == c1_masked)
-                    {
-                        scan++;
-                    }
+                    scan = (char *) find_span_end_mask((U8 *) scan,
+                                                       (U8 *) loceol,
+                                                       c1 & c1_c2_mask,
+                                                       c1_c2_mask);
                 }
                 else {
                     while (    scan < loceol
@@ -9283,7 +9354,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
        }
        break;
 
-    case ASCII:
+    case ANYOFM:
         if (utf8_target && loceol - scan > max) {
 
             /* We didn't adjust <loceol> at the beginning of this routine
@@ -9292,6 +9363,14 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
             loceol = scan + max;
         }
 
+        scan = (char *) find_span_end_mask((U8 *) scan, (U8 *) loceol, (U8) ARG(p), FLAGS(p));
+        break;
+
+    case ASCII:
+        if (utf8_target && loceol - scan > max) {
+            loceol = scan + max;
+        }
+
         scan = find_next_non_ascii(scan, loceol, utf8_target);
        break;
 
@@ -9327,7 +9406,8 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
        } else {
            while (hardcount < max && scan < loceol
                    && to_complement ^ cBOOL(isFOO_utf8_lc(FLAGS(p),
-                                                                  (U8 *) scan)))
+                                                                  (U8 *) scan,
+                                                                  (U8 *) loceol)))
             {
                 scan += UTF8SKIP(scan);
                hardcount++;
@@ -9396,130 +9476,80 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
        else {
           utf8_posix:
             classnum = (_char_class_number) FLAGS(p);
-            if (classnum < _FIRST_NON_SWASH_CC) {
-
-                /* Here, a swash is needed for above-Latin1 code points.
-                 * Process as many Latin1 code points using the built-in rules.
-                 * Go to another loop to finish processing upon encountering
-                 * the first Latin1 code point.  We could do that in this loop
-                 * as well, but the other way saves having to test if the swash
-                 * has been loaded every time through the loop: extra space to
-                 * save a test. */
-                while (hardcount < max && scan < loceol) {
-                    if (UTF8_IS_INVARIANT(*scan)) {
-                        if (! (to_complement ^ cBOOL(_generic_isCC((U8) *scan,
-                                                                   classnum))))
-                        {
-                            break;
-                        }
-                        scan++;
+            switch (classnum) {
+                default:
+                    while (   hardcount < max && scan < loceol
+                           && to_complement ^ cBOOL(_invlist_contains_cp(
+                                              PL_XPosix_ptrs[classnum],
+                                              utf8_to_uvchr_buf((U8 *) scan,
+                                                                (U8 *) loceol,
+                                                                NULL))))
+                    {
+                        scan += UTF8SKIP(scan);
+                        hardcount++;
                     }
-                    else if (UTF8_IS_DOWNGRADEABLE_START(*scan)) {
-                        if (! (to_complement
-                              ^ cBOOL(_generic_isCC(EIGHT_BIT_UTF8_TO_NATIVE(*scan,
-                                                                     *(scan + 1)),
-                                                    classnum))))
-                        {
-                            break;
-                        }
-                        scan += 2;
+                    break;
+
+                    /* For the classes below, the knowledge of how to handle
+                     * every code point is compiled in to Perl via a macro.
+                     * This code is written for making the loops as tight as
+                     * possible.  It could be refactored to save space instead.
+                     * */
+
+                case _CC_ENUM_SPACE:
+                    while (hardcount < max
+                           && scan < loceol
+                           && (to_complement
+                               ^ cBOOL(isSPACE_utf8_safe(scan, loceol))))
+                    {
+                        scan += UTF8SKIP(scan);
+                        hardcount++;
                     }
-                    else {
-                        goto found_above_latin1;
+                    break;
+                case _CC_ENUM_BLANK:
+                    while (hardcount < max
+                           && scan < loceol
+                           && (to_complement
+                                ^ cBOOL(isBLANK_utf8_safe(scan, loceol))))
+                    {
+                        scan += UTF8SKIP(scan);
+                        hardcount++;
                     }
-
-                    hardcount++;
-                }
-            }
-            else {
-                /* For these character classes, the knowledge of how to handle
-                 * every code point is compiled in to Perl via a macro.  This
-                 * code is written for making the loops as tight as possible.
-                 * It could be refactored to save space instead */
-                switch (classnum) {
-                    case _CC_ENUM_SPACE:
-                        while (hardcount < max
-                               && scan < loceol
-                               && (to_complement
-                                   ^ cBOOL(isSPACE_utf8_safe(scan, loceol))))
-                        {
-                            scan += UTF8SKIP(scan);
-                            hardcount++;
-                        }
-                        break;
-                    case _CC_ENUM_BLANK:
-                        while (hardcount < max
-                               && scan < loceol
-                               && (to_complement
-                                    ^ cBOOL(isBLANK_utf8_safe(scan, loceol))))
-                        {
-                            scan += UTF8SKIP(scan);
-                            hardcount++;
-                        }
-                        break;
-                    case _CC_ENUM_XDIGIT:
-                        while (hardcount < max
-                               && scan < loceol
-                               && (to_complement
-                                   ^ cBOOL(isXDIGIT_utf8_safe(scan, loceol))))
-                        {
-                            scan += UTF8SKIP(scan);
-                            hardcount++;
-                        }
-                        break;
-                    case _CC_ENUM_VERTSPACE:
-                        while (hardcount < max
-                               && scan < loceol
-                               && (to_complement
-                                   ^ cBOOL(isVERTWS_utf8_safe(scan, loceol))))
-                        {
-                            scan += UTF8SKIP(scan);
-                            hardcount++;
-                        }
-                        break;
-                    case _CC_ENUM_CNTRL:
-                        while (hardcount < max
-                               && scan < loceol
-                               && (to_complement
-                                   ^ cBOOL(isCNTRL_utf8_safe(scan, loceol))))
-                        {
-                            scan += UTF8SKIP(scan);
-                            hardcount++;
-                        }
-                        break;
-                    default:
-                        Perl_croak(aTHX_ "panic: regrepeat() node %d='%s' has an unexpected character class '%d'", OP(p), PL_reg_name[OP(p)], classnum);
-                }
+                    break;
+                case _CC_ENUM_XDIGIT:
+                    while (hardcount < max
+                           && scan < loceol
+                           && (to_complement
+                               ^ cBOOL(isXDIGIT_utf8_safe(scan, loceol))))
+                    {
+                        scan += UTF8SKIP(scan);
+                        hardcount++;
+                    }
+                    break;
+                case _CC_ENUM_VERTSPACE:
+                    while (hardcount < max
+                           && scan < loceol
+                           && (to_complement
+                               ^ cBOOL(isVERTWS_utf8_safe(scan, loceol))))
+                    {
+                        scan += UTF8SKIP(scan);
+                        hardcount++;
+                    }
+                    break;
+                case _CC_ENUM_CNTRL:
+                    while (hardcount < max
+                           && scan < loceol
+                           && (to_complement
+                               ^ cBOOL(isCNTRL_utf8_safe(scan, loceol))))
+                    {
+                        scan += UTF8SKIP(scan);
+                        hardcount++;
+                    }
+                    break;
             }
        }
         break;
 
-      found_above_latin1:   /* Continuation of POSIXU and NPOSIXU */
-
-        /* Load the swash if not already present */
-        if (! PL_utf8_swash_ptrs[classnum]) {
-            U8 flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-            PL_utf8_swash_ptrs[classnum] = _core_swash_init(
-                                        "utf8",
-                                        "",
-                                        &PL_sv_undef, 1, 0,
-                                        PL_XPosix_ptrs[classnum], &flags);
-        }
-
-        while (hardcount < max && scan < loceol
-               && to_complement ^ cBOOL(_generic_utf8_safe(
-                                       classnum,
-                                       scan,
-                                       loceol,
-                                       swash_fetch(PL_utf8_swash_ptrs[classnum],
-                                                   (U8 *) scan,
-                                                   TRUE))))
-        {
-            scan += UTF8SKIP(scan);
-            hardcount++;
-        }
-        break;
-
     case LNBREAK:
         if (utf8_target) {
            while (hardcount < max && scan < loceol &&
@@ -10156,15 +10186,55 @@ Perl__is_grapheme(pTHX_ const U8 * strbeg, const U8 * s, const U8 * strend, cons
     return isGCB(cp_gcb_val, next_cp_gcb_val, strbeg, s, TRUE);
 }
 
+/*
+=head1 Unicode Support
+
+=for apidoc isSCRIPT_RUN
+
+Returns a bool as to whether or not the sequence of bytes from C<s> up to but
+not including C<send> form a "script run".  C<utf8_target> is TRUE iff the
+sequence starting at C<s> is to be treated as UTF-8.  To be precise, except for
+two degenerate cases given below, this function returns TRUE iff all code
+points in it come from any combination of three "scripts" given by the Unicode
+"Script Extensions" property: Common, Inherited, and possibly one other.
+Additionally all decimal digits must come from the same consecutive sequence of
+10.
+
+For example, if all the characters in the sequence are Greek, or Common, or
+Inherited, this function will return TRUE, provided any decimal digits in it
+are the ASCII digits "0".."9".  For scripts (unlike Greek) that have their own
+digits defined this will accept either digits from that set or from 0..9, but
+not a combination of the two.  Some scripts, such as Arabic, have more than one
+set of digits.  All digits must come from the same set for this function to
+return TRUE.
+
+C<*ret_script>, if C<ret_script> is not NULL, will on return of TRUE
+contain the script found, using the C<SCX_enum> typedef.  Its value will be
+C<SCX_INVALID> if the function returns FALSE.
+
+If the sequence is empty, TRUE is returned, but C<*ret_script> (if asked for)
+will be C<SCX_INVALID>.
+
+If the sequence contains a single code point which is unassigned to a character
+in the version of Unicode being used, the function will return TRUE, and the
+script will be C<SCX_Unknown>.  Any other combination of unassigned code points
+in the input sequence will result in the function treating the input as not
+being a script run.
+
+The returned script will be C<SCX_Inherited> iff all the code points in it are
+from the Inherited script.
+
+Otherwise, the returned script will be C<SCX_Common> iff all the code points in
+it are from the Inherited or Common scripts.
+
+=cut
+
+*/
+
 bool
 Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
 {
-    /* Checks that every character in the sequence from 's' to 'send' is one of
-     * three scripts: Common, Inherited, and possibly one other.  Additionally
-     * all decimal digits must come from the same consecutive sequence of 10.
-     * 'utf8_target' is TRUE iff the sequence is encoded in UTF-8.
-     *
-     * Basically, it looks at each character in the sequence to see if the
+    /* Basically, it looks at each character in the sequence to see if the
      * above conditions are met; if not it fails.  It uses an inversion map to
      * find the enum corresponding to the script of each character.  But this
      * is complicated by the fact that a few code points can be in any of
@@ -10212,10 +10282,33 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
 
     bool retval = TRUE;
 
-    assert(send > s);
+    /* This is supposed to be a return parameter, but currently unused */
+    SCX_enum * ret_script = NULL;
+
+    assert(send >= s);
 
     PERL_ARGS_ASSERT_ISSCRIPT_RUN;
 
+    /* All code points in 0..255 are either Common or Latin, so must be a
+     * script run.  We can special case it */
+    if (! utf8_target && LIKELY(send > s)) {
+        if (ret_script == NULL) {
+            return TRUE;
+        }
+
+        /* If any character is Latin, the run is Latin */
+        while (s < send) {
+            if (isALPHA_L1(*s) && LIKELY(*s != MICRO_SIGN_NATIVE)) {
+                *ret_script = SCX_Latin;
+                return TRUE;
+            }
+        }
+
+        /* If all are Common ... */
+        *ret_script = SCX_Common;
+        return TRUE;
+    }
+
     /* Look at each character in the sequence */
     while (s < send) {
         UV cp;
@@ -10224,8 +10317,12 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
          * because they are used in commerce even in scripts that have their
          * own set.  Hence any ASCII ones found are ok, unless a digit from
          * another set has already been encountered.  (The other digit ranges
-         * in Common are not similarly blessed */
+         * in Common are not similarly blessed) */
         if (UNLIKELY(isDIGIT(*s))) {
+            if (UNLIKELY(script_of_run == SCX_Unknown)) {
+                retval = FALSE;
+                break;
+            }
             if (zero_of_run > 0) {
                 if (zero_of_run != '0') {
                     retval = FALSE;
@@ -10240,7 +10337,7 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
         }
 
         /* Here, isn't an ASCII digit.  Find the code point of the character */
-        if (utf8_target && ! UTF8_IS_INVARIANT(*s)) {
+        if (! UTF8_IS_INVARIANT(*s)) {
             Size_t len;
             cp = valid_utf8_to_uvchr((U8 *) s, &len);
             s += len;
@@ -10288,9 +10385,20 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
             break;
         }
 
+        /* For the first character, or the run is inherited, the run's script
+         * is set to the char's */
+        if (   UNLIKELY(script_of_run == SCX_INVALID)
+            || UNLIKELY(script_of_run == SCX_Inherited))
+        {
+            script_of_run = script_of_char;
+        }
+
+        /* For the character's script to be Unknown, it must be the first
+         * character in the sequence (for otherwise a test above would have
+         * prevented us from reaching here), and we have set the run's script
+         * to it.  Nothing further to be done for this character */
         if (UNLIKELY(script_of_char == SCX_Unknown)) {
-                script_of_run = SCX_Unknown;
-                continue;
+            continue;
         }
 
         /* We accept 'inherited' script characters currently even at the
@@ -10300,8 +10408,17 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
             continue;
         }
 
-        /* If unknown, the run's script is set to the char's */
-        if (UNLIKELY(script_of_run == SCX_INVALID)) {
+        /* If the run so far is Common, and the new character isn't, change the
+         * run's script to that of this character */
+        if (script_of_run == SCX_Common && script_of_char != SCX_Common) {
+
+            /* But Common contains several sets of digits.  Only the '0' set
+             * can be part of another script. */
+            if (zero_of_run > 0 && zero_of_run != '0') {
+                retval = FALSE;
+                break;
+            }
+
             script_of_run = script_of_char;
         }
 
@@ -10322,22 +10439,6 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
             goto scripts_match;
         }
 
-        /* Here, the scripts of the run and the current character don't match
-         * exactly.  The run could so far have been entirely characters from
-         * Common.  It's now time to change its script to that of this
-         * non-Common character */
-        if (script_of_run == SCX_Common) {
-
-            /* But Common contains several sets of digits.  Only the '0' set
-             * can be part of another script. */
-            if (zero_of_run > 0 && zero_of_run != '0') {
-                retval = FALSE;
-                break;
-            }
-
-            script_of_run = script_of_char;
-            goto scripts_match;
-        }
 
         /* Here, the script of the run isn't Common.  But characters in Common
          * match any script */
@@ -10349,6 +10450,7 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
 
         /* Too early a Unicode version to have a code point belonging to more
          * than one script, so, if the scripts don't exactly match, fail */
+        PERL_UNUSED_VAR(intersection_len);
         retval = FALSE;
         break;
 
@@ -10521,6 +10623,16 @@ Perl_isSCRIPT_RUN(pTHX_ const U8 * s, const U8 * send, const bool utf8_target)
     } /* end of looping through CLOSESR text */
 
     Safefree(intersection);
+
+    if (ret_script != NULL) {
+        if (retval) {
+            *ret_script = script_of_run;
+        }
+        else {
+            *ret_script = SCX_INVALID;
+        }
+    }
+
     return retval;
 }