This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
perldelta for 412989c
[perl5.git] / regexec.c
index e3ce022..9297d76 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -288,7 +288,6 @@ static regmatch_state * S_push_slab(pTHX);
 STATIC CHECKPOINT
 S_regcppush(pTHX_ const regexp *rex, I32 parenfloor, U32 maxopenparen)
 {
-    dVAR;
     const int retval = PL_savestack_ix;
     const int paren_elems_to_push =
                 (maxopenparen - parenfloor) * REGCP_PAREN_ELEMS;
@@ -300,8 +299,9 @@ S_regcppush(pTHX_ const regexp *rex, I32 parenfloor, U32 maxopenparen)
     PERL_ARGS_ASSERT_REGCPPUSH;
 
     if (paren_elems_to_push < 0)
-        Perl_croak(aTHX_ "panic: paren_elems_to_push, %i < 0, maxopenparen: %i parenfloor: %i REGCP_PAREN_ELEMS: %i",
-                   paren_elems_to_push, maxopenparen, parenfloor, REGCP_PAREN_ELEMS);
+        Perl_croak(aTHX_ "panic: paren_elems_to_push, %i < 0, maxopenparen: %i parenfloor: %i REGCP_PAREN_ELEMS: %u",
+                   (int)paren_elems_to_push, (int)maxopenparen,
+                   (int)parenfloor, (unsigned)REGCP_PAREN_ELEMS);
 
     if ((elems_shifted >> SAVE_TIGHT_SHIFT) != total_elems)
        Perl_croak(aTHX_ "panic: paren_elems_to_push offset %"UVuf
@@ -368,7 +368,6 @@ S_regcppush(pTHX_ const regexp *rex, I32 parenfloor, U32 maxopenparen)
 STATIC void
 S_regcppop(pTHX_ regexp *rex, U32 *maxopenparen_p)
 {
-    dVAR;
     UV i;
     U32 paren;
     GET_RE_DEBUG_FLAGS_DECL;
@@ -537,12 +536,10 @@ S_isFOO_utf8_lc(pTHX_ const U8 classnum, const U8* 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:                 return 0;  /* Things like CNTRL are always
-                                               below 256 */
+        default:                 break;
     }
 
-    assert(0); /* NOTREACHED */
-    return FALSE;
+    return FALSE; /* Things like CNTRL are always below 256 */
 }
 
 /*
@@ -648,7 +645,6 @@ Perl_re_intuit_start(pTHX_
                     const U32 flags,
                     re_scream_pos_data *data)
 {
-    dVAR;
     struct regexp *const prog = ReANY(rx);
     SSize_t start_shift = prog->check_offset_min;
     /* Should be nonnegative! */
@@ -752,20 +748,31 @@ Perl_re_intuit_start(pTHX_
     });
 
     if (prog->intflags & PREGf_ANCH) { /* Match at \G, beg-of-str or after \n */
-        /* Check after \n? */
-       ml_anch = (prog->intflags & PREGf_ANCH_MBOL);
 
-       if (!ml_anch) {
+        /* ml_anch: check after \n?
+         *
+         * A note about IMPLICIT: on an un-anchored pattern beginning
+         * with /.*.../, these flags will have been added by the
+         * compiler:
+         *   /.*abc/, /.*abc/m:  PREGf_IMPLICIT | PREGf_ANCH_MBOL
+         *   /.*abc/s:           PREGf_IMPLICIT | PREGf_ANCH_SBOL
+         */
+       ml_anch =      (prog->intflags & PREGf_ANCH_MBOL)
+                   && !(prog->intflags & PREGf_IMPLICIT);
+
+       if (!ml_anch && !(prog->intflags & PREGf_IMPLICIT)) {
             /* we are only allowed to match at BOS or \G */
 
             /* trivially reject if there's a BOS anchor and we're not at BOS.
-             * In the case of \G, we hope(!) that the caller has already
-             * set strpos to pos()-gofs, and will already have checked
-             * that this anchor position is legal. So we can skip it here.
+             *
+             * Note that we don't try to do a similar quick reject for
+             * \G, since generally the caller will have calculated strpos
+             * based on pos() and gofs, so the string is already correctly
+             * anchored by definition; and handling the exceptions would
+             * be too fiddly (e.g. REXEC_IGNOREPOS).
              */
-            if (   !(prog->intflags & PREGf_ANCH_GPOS)
-                && !(prog->intflags & PREGf_IMPLICIT) /* not a real BOL */
-               && (strpos != strbeg))
+            if (   strpos != strbeg
+                && (prog->intflags & PREGf_ANCH_SBOL))
             {
                DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
                                 "  Not at start...\n"));
@@ -787,20 +794,21 @@ Perl_re_intuit_start(pTHX_
             {
                /* Substring at constant offset from beg-of-str... */
                SSize_t slen = SvCUR(check);
-                char *s;
-
-               s = HOP3c(strpos, prog->check_offset_min, strend);
+                char *s = HOP3c(strpos, prog->check_offset_min, strend);
            
                 DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
                     "  Looking for check substr at fixed offset %"IVdf"...\n",
                     (IV)prog->check_offset_min));
 
-               if (SvTAIL(check) && !multiline) {
-                    /* In this case, the regex is anchored at the end too,
-                     * so the lengths must match exactly, give or take a \n.
-                    * NB: slen >= 1 since the last char of check is \n */
-                   if (   strend - s > slen || strend - s < slen - 1
-                      || (strend - s == slen && strend[-1] != '\n'))
+               if (SvTAIL(check)) {
+                    /* In this case, the regex is anchored at the end too.
+                     * Unless it's a multiline match, the lengths must match
+                     * exactly, give or take a \n.  NB: slen >= 1 since
+                     * the last char of check is \n */
+                   if (!multiline
+                        && (   strend - s > slen
+                            || strend - s < slen - 1
+                            || (strend - s == slen && strend[-1] != '\n')))
                     {
                         DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
                                             "  String too long...\n"));
@@ -887,19 +895,32 @@ Perl_re_intuit_start(pTHX_
        }
 
 
-        /* if the regex is absolutely anchored to the start of the string,
-         * then check_offset_max represents an upper bound on the string
-         * where the substr could start */
+        /* If the regex is absolutely anchored to either the start of the
+         * string (SBOL) or to pos() (ANCH_GPOS), then
+         * check_offset_max represents an upper bound on the string where
+         * the substr could start. For the ANCH_GPOS case, we assume that
+         * the caller of intuit will have already set strpos to
+         * pos()-gofs, so in this case strpos + offset_max will still be
+         * an upper bound on the substr.
+         */
         if (!ml_anch
             && prog->intflags & PREGf_ANCH
-            && prog->check_offset_max != SSize_t_MAX
-            && start_shift < prog->check_offset_max)
+            && prog->check_offset_max != SSize_t_MAX)
         {
             SSize_t len = SvCUR(check) - !!SvTAIL(check);
-            end_point = HOP3lim(start_point,
-                            prog->check_offset_max - start_shift,
-                            end_point -len)
-                        + len;
+            const char * const anchor =
+                        (prog->intflags & PREGf_ANCH_GPOS ? strpos : strbeg);
+
+            /* do a bytes rather than chars comparison. It's conservative;
+             * so it skips doing the HOP if the result can't possibly end
+             * up earlier than the old value of end_point.
+             */
+            if ((char*)end_point - anchor > prog->check_offset_max) {
+                end_point = HOP3lim((U8*)anchor,
+                                prog->check_offset_max,
+                                end_point -len)
+                            + len;
+            }
         }
 
        DEBUG_OPTIMISE_MORE_r({
@@ -1123,10 +1144,7 @@ Perl_re_intuit_start(pTHX_
 
     /* handle the extra constraint of /^.../m if present */
 
-    if (ml_anch && rx_origin != strbeg && rx_origin[-1] != '\n'
-        /* May be due to an implicit anchor of m{.*foo}  */
-        && !(prog->intflags & PREGf_IMPLICIT))
-    {
+    if (ml_anch && rx_origin != strbeg && rx_origin[-1] != '\n') {
         char *s;
 
         DEBUG_EXECUTE_r(PerlIO_printf(Perl_debug_log,
@@ -1271,7 +1289,8 @@ Perl_re_intuit_start(pTHX_
            }
            DEBUG_EXECUTE_r( PerlIO_printf(Perl_debug_log,
                                "  This position contradicts STCLASS...\n") );
-            if ((prog->intflags & PREGf_ANCH) && !ml_anch)
+            if ((prog->intflags & PREGf_ANCH) && !ml_anch
+                        && !(prog->intflags & PREGf_IMPLICIT))
                goto fail;
 
            /* Contradict one of substrings */
@@ -1389,19 +1408,10 @@ Perl_re_intuit_start(pTHX_
            prog->check_substr = prog->check_utf8 = NULL;       /* disable */
            prog->float_substr = prog->float_utf8 = NULL;       /* clear */
            check = NULL;                       /* abort */
-           /* XXXX If the check string was an implicit check MBOL, then we need to unset the relevant flag
-                   see http://bugs.activestate.com/show_bug.cgi?id=87173 */
-            if (prog->intflags & PREGf_IMPLICIT) {
-                prog->intflags &= ~PREGf_ANCH_MBOL;
-                /* maybe we have no anchors left after this... */
-                if (!(prog->intflags & PREGf_ANCH))
-                    prog->extflags &= ~RXf_IS_ANCHORED;
-            }
            /* XXXX This is a remnant of the old implementation.  It
                    looks wasteful, since now INTUIT can use many
                    other heuristics. */
            prog->extflags &= ~RXf_USE_INTUIT;
-           /* XXXX What other flags might need to be cleared in this branch? */
        }
     }
 
@@ -1437,7 +1447,7 @@ STMT_START {
     switch (trie_type) {                                                            \
     case trie_utf8_exactfa_fold:                                                    \
         flags |= FOLD_FLAGS_NOMIX_ASCII;                                            \
-        /* FALL THROUGH */                                                          \
+        /* FALLTHROUGH */                                                          \
     case trie_utf8_fold:                                                            \
         if ( foldlen>0 ) {                                                          \
             uvc = utf8n_to_uvchr( (const U8*) uscan, UTF8_MAXLEN, &len, uniflags ); \
@@ -1454,7 +1464,7 @@ STMT_START {
         break;                                                                      \
     case trie_latin_utf8_exactfa_fold:                                              \
         flags |= FOLD_FLAGS_NOMIX_ASCII;                                            \
-        /* FALL THROUGH */                                                          \
+        /* FALLTHROUGH */                                                          \
     case trie_latin_utf8_fold:                                                      \
         if ( foldlen>0 ) {                                                          \
             uvc = utf8n_to_uvchr( (const U8*) uscan, UTF8_MAXLEN, &len, uniflags ); \
@@ -1490,10 +1500,14 @@ STMT_START {
     }                                                                               \
 } STMT_END
 
-#define REXEC_FBC_EXACTISH_SCAN(CoNd)                     \
+#define DUMP_EXEC_POS(li,s,doutf8)                          \
+    dump_exec_pos(li,s,(reginfo->strend),(reginfo->strbeg), \
+                startpos, doutf8)
+
+#define REXEC_FBC_EXACTISH_SCAN(COND)                     \
 STMT_START {                                              \
     while (s <= e) {                                      \
-       if ( (CoNd)                                       \
+       if ( (COND)                                       \
             && (ln == 1 || folder(s, pat_string, ln))    \
             && (reginfo->intuit || regtry(reginfo, &s)) )\
            goto got_it;                                  \
@@ -1501,148 +1515,199 @@ STMT_START {                                              \
     }                                                     \
 } STMT_END
 
-#define REXEC_FBC_UTF8_SCAN(CoDe)                     \
+#define REXEC_FBC_UTF8_SCAN(CODE)                     \
 STMT_START {                                          \
     while (s < strend) {                              \
-       CoDe                                          \
+       CODE                                          \
        s += UTF8SKIP(s);                             \
     }                                                 \
 } STMT_END
 
-#define REXEC_FBC_SCAN(CoDe)                          \
+#define REXEC_FBC_SCAN(CODE)                          \
 STMT_START {                                          \
     while (s < strend) {                              \
-       CoDe                                          \
+       CODE                                          \
        s++;                                          \
     }                                                 \
 } STMT_END
 
-#define REXEC_FBC_UTF8_CLASS_SCAN(CoNd)               \
-REXEC_FBC_UTF8_SCAN(                                  \
-    if (CoNd) {                                       \
-       if (tmp && (reginfo->intuit || regtry(reginfo, &s))) \
-           goto got_it;                              \
-       else                                          \
-           tmp = doevery;                            \
-    }                                                 \
-    else                                              \
-       tmp = 1;                                      \
+#define REXEC_FBC_UTF8_CLASS_SCAN(COND)                        \
+REXEC_FBC_UTF8_SCAN( /* Loops while (s < strend) */            \
+    if (COND) {                                                \
+       if (tmp && (reginfo->intuit || regtry(reginfo, &s)))   \
+           goto got_it;                                       \
+       else                                                   \
+           tmp = doevery;                                     \
+    }                                                          \
+    else                                                       \
+       tmp = 1;                                               \
 )
 
-#define REXEC_FBC_CLASS_SCAN(CoNd)                    \
-REXEC_FBC_SCAN(                                       \
-    if (CoNd) {                                       \
-       if (tmp && (reginfo->intuit || regtry(reginfo, &s)))  \
-           goto got_it;                              \
-       else                                          \
-           tmp = doevery;                            \
-    }                                                 \
-    else                                              \
-       tmp = 1;                                      \
+#define REXEC_FBC_CLASS_SCAN(COND)                             \
+REXEC_FBC_SCAN( /* Loops while (s < strend) */                 \
+    if (COND) {                                                \
+       if (tmp && (reginfo->intuit || regtry(reginfo, &s)))   \
+           goto got_it;                                       \
+       else                                                   \
+           tmp = doevery;                                     \
+    }                                                          \
+    else                                                       \
+       tmp = 1;                                               \
 )
 
-#define REXEC_FBC_TRYIT                       \
-if ((reginfo->intuit || regtry(reginfo, &s))) \
-    goto got_it
-
-#define REXEC_FBC_CSCAN(CoNdUtF8,CoNd)                         \
+#define REXEC_FBC_CSCAN(CONDUTF8,COND)                         \
     if (utf8_target) {                                         \
-       REXEC_FBC_UTF8_CLASS_SCAN(CoNdUtF8);                   \
+       REXEC_FBC_UTF8_CLASS_SCAN(CONDUTF8);                   \
     }                                                          \
     else {                                                     \
-       REXEC_FBC_CLASS_SCAN(CoNd);                            \
+       REXEC_FBC_CLASS_SCAN(COND);                            \
     }
-    
-#define DUMP_EXEC_POS(li,s,doutf8)                          \
-    dump_exec_pos(li,s,(reginfo->strend),(reginfo->strbeg), \
-                startpos, doutf8)
-
 
-#define UTF8_NOLOAD(TEST_NON_UTF8, IF_SUCCESS, IF_FAIL)                        \
-       tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n';                  \
-       tmp = TEST_NON_UTF8(tmp);                                              \
-       REXEC_FBC_UTF8_SCAN(                                                   \
-           if (tmp == ! TEST_NON_UTF8((U8) *s)) {                             \
-               tmp = !tmp;                                                    \
-               IF_SUCCESS;                                                    \
-           }                                                                  \
-           else {                                                             \
-               IF_FAIL;                                                       \
-           }                                                                  \
-       );                                                                     \
-
-#define UTF8_LOAD(TeSt1_UtF8, TeSt2_UtF8, IF_SUCCESS, IF_FAIL)                 \
-       if (s == reginfo->strbeg) {                                            \
-           tmp = '\n';                                                        \
-       }                                                                      \
-       else {                                                                 \
-           U8 * const r = reghop3((U8*)s, -1, (U8*)reginfo->strbeg);          \
-           tmp = utf8n_to_uvchr(r, (U8*) reginfo->strend - r,                 \
+/* The three macros below are slightly different versions of the same logic.
+ *
+ * The first is for /a and /aa when the target string is UTF-8.  This can only
+ * match ascii, but it must advance based on UTF-8.   The other two handle the
+ * non-UTF-8 and the more generic UTF-8 cases.   In all three, we are looking
+ * for the boundary (or non-boundary) between a word and non-word character.
+ * The utf8 and non-utf8 cases have the same logic, but the details must be
+ * different.  Find the "wordness" of the character just prior to this one, and
+ * compare it with the wordness of this one.  If they differ, we have a
+ * boundary.  At the beginning of the string, pretend that the previous
+ * character was a new-line.
+ *
+ * All these macros uncleanly have side-effects with each other and outside
+ * variables.  So far it's been too much trouble to clean-up
+ *
+ * TEST_NON_UTF8 is the macro or function to call to test if its byte input is
+ *               a word character or not.
+ * IF_SUCCESS    is code to do if it finds that we are at a boundary between
+ *               word/non-word
+ * IF_FAIL       is code to do if we aren't at a boundary between word/non-word
+ *
+ * Exactly one of the two IF_FOO parameters is a no-op, depending on whether we
+ * are looking for a boundary or for a non-boundary.  If we are looking for a
+ * boundary, we want IF_FAIL to be the no-op, and for IF_SUCCESS to go out and
+ * see if this tentative match actually works, and if so, to quit the loop
+ * here.  And vice-versa if we are looking for a non-boundary.
+ *
+ * 'tmp' below in the next three macros in the REXEC_FBC_SCAN and
+ * REXEC_FBC_UTF8_SCAN loops is a loop invariant, a bool giving the return of
+ * TEST_NON_UTF8(s-1).  To see this, note that that's what it is defined to be
+ * at entry to the loop, and to get to the IF_FAIL branch, tmp must equal
+ * TEST_NON_UTF8(s), and in the opposite branch, IF_SUCCESS, tmp is that
+ * complement.  But in that branch we complement tmp, meaning that at the
+ * bottom of the loop tmp is always going to be equal to TEST_NON_UTF8(s),
+ * which means at the top of the loop in the next iteration, it is
+ * TEST_NON_UTF8(s-1) */
+#define FBC_UTF8_A(TEST_NON_UTF8, IF_SUCCESS, IF_FAIL)                         \
+    tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n';                      \
+    tmp = TEST_NON_UTF8(tmp);                                                  \
+    REXEC_FBC_UTF8_SCAN( /* advances s while s < strend */                     \
+        if (tmp == ! TEST_NON_UTF8((U8) *s)) {                                 \
+            tmp = !tmp;                                                        \
+            IF_SUCCESS; /* Is a boundary if values for s-1 and s differ */     \
+        }                                                                      \
+        else {                                                                 \
+            IF_FAIL;                                                           \
+        }                                                                      \
+    );                                                                         \
+
+/* Like FBC_UTF8_A, but TEST_UV is a macro which takes a UV as its input, and
+ * TEST_UTF8 is a macro that for the same input code points returns identically
+ * to TEST_UV, but takes a pointer to a UTF-8 encoded string instead */
+#define FBC_UTF8(TEST_UV, TEST_UTF8, IF_SUCCESS, IF_FAIL)                      \
+    if (s == reginfo->strbeg) {                                                \
+        tmp = '\n';                                                            \
+    }                                                                          \
+    else { /* Back-up to the start of the previous character */                \
+        U8 * const r = reghop3((U8*)s, -1, (U8*)reginfo->strbeg);              \
+        tmp = utf8n_to_uvchr(r, (U8*) reginfo->strend - r,                     \
                                                        0, UTF8_ALLOW_DEFAULT); \
-       }                                                                      \
-       tmp = TeSt1_UtF8;                                                      \
-       LOAD_UTF8_CHARCLASS_ALNUM();                                           \
-       REXEC_FBC_UTF8_SCAN(                                                   \
-           if (tmp == ! (TeSt2_UtF8)) {                                       \
-               tmp = !tmp;                                                    \
-               IF_SUCCESS;                                                    \
-           }                                                                  \
-           else {                                                             \
-               IF_FAIL;                                                       \
-           }                                                                  \
-       );                                                                     \
+    }                                                                          \
+    tmp = TEST_UV(tmp);                                                        \
+    LOAD_UTF8_CHARCLASS_ALNUM();                                               \
+    REXEC_FBC_UTF8_SCAN( /* advances s while s < strend */                     \
+        if (tmp == ! (TEST_UTF8((U8 *) s))) {                                  \
+            tmp = !tmp;                                                        \
+            IF_SUCCESS;                                                        \
+        }                                                                      \
+        else {                                                                 \
+            IF_FAIL;                                                           \
+        }                                                                      \
+    );
 
-/* The only difference between the BOUND and NBOUND cases is that
- * REXEC_FBC_TRYIT is called when matched in BOUND, and when non-matched in
- * NBOUND.  This is accomplished by passing it in either the if or else clause,
- * with the other one being empty */
-#define FBC_BOUND(TEST_NON_UTF8, TEST1_UTF8, TEST2_UTF8) \
-    FBC_BOUND_COMMON(UTF8_LOAD(TEST1_UTF8, TEST2_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER), TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
-
-#define FBC_BOUND_NOLOAD(TEST_NON_UTF8, TEST1_UTF8, TEST2_UTF8) \
-    FBC_BOUND_COMMON(UTF8_NOLOAD(TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER), TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
-
-#define FBC_NBOUND(TEST_NON_UTF8, TEST1_UTF8, TEST2_UTF8) \
-    FBC_BOUND_COMMON(UTF8_LOAD(TEST1_UTF8, TEST2_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT), TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
-
-#define FBC_NBOUND_NOLOAD(TEST_NON_UTF8, TEST1_UTF8, TEST2_UTF8) \
-    FBC_BOUND_COMMON(UTF8_NOLOAD(TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT), TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
-
-
-/* Common to the BOUND and NBOUND cases.  Unfortunately the UTF8 tests need to
- * be passed in completely with the variable name being tested, which isn't
- * such a clean interface, but this is easier to read than it was before.  We
- * are looking for the boundary (or non-boundary between a word and non-word
- * character.  The utf8 and non-utf8 cases have the same logic, but the details
- * must be different.  Find the "wordness" of the character just prior to this
- * one, and compare it with the wordness of this one.  If they differ, we have
- * a boundary.  At the beginning of the string, pretend that the previous
- * character was a new-line */
+/* Like the above two macros.  UTF8_CODE is the complete code for handling
+ * UTF-8.  Common to the BOUND and NBOUND cases, set-up by the FBC_BOUND, etc
+ * macros below */
 #define FBC_BOUND_COMMON(UTF8_CODE, TEST_NON_UTF8, IF_SUCCESS, IF_FAIL)        \
     if (utf8_target) {                                                         \
-               UTF8_CODE                                                      \
+        UTF8_CODE                                                              \
     }                                                                          \
     else {  /* Not utf8 */                                                     \
        tmp = (s != reginfo->strbeg) ? UCHARAT(s - 1) : '\n';                  \
        tmp = TEST_NON_UTF8(tmp);                                              \
-       REXEC_FBC_SCAN(                                                        \
+       REXEC_FBC_SCAN( /* advances s while s < strend */                      \
            if (tmp == ! TEST_NON_UTF8((U8) *s)) {                             \
-               tmp = !tmp;                                                    \
                IF_SUCCESS;                                                    \
+               tmp = !tmp;                                                    \
            }                                                                  \
            else {                                                             \
                IF_FAIL;                                                       \
            }                                                                  \
        );                                                                     \
     }                                                                          \
-    if ((!prog->minlen && tmp) && (reginfo->intuit || regtry(reginfo, &s)))    \
-       goto got_it;
+    /* Here, things have been set up by the previous code so that tmp is the   \
+     * return of TEST_NON_UTF(s-1) or TEST_UTF8(s-1) (depending on the         \
+     * utf8ness of the target).  We also have to check if this matches against \
+     * the EOS, which we treat as a \n (which is the same value in both UTF-8  \
+     * or non-UTF8, so can use the non-utf8 test condition even for a UTF-8    \
+     * string */                                                               \
+    if (tmp == ! TEST_NON_UTF8('\n')) {                                        \
+        IF_SUCCESS;                                                            \
+    }                                                                          \
+    else {                                                                     \
+        IF_FAIL;                                                               \
+    }
+
+/* This is the macro to use when we want to see if something that looks like it
+ * could match, actually does, and if so exits the loop */
+#define REXEC_FBC_TRYIT                            \
+    if ((reginfo->intuit || regtry(reginfo, &s)))  \
+        goto got_it
+
+/* The only difference between the BOUND and NBOUND cases is that
+ * REXEC_FBC_TRYIT is called when matched in BOUND, and when non-matched in
+ * NBOUND.  This is accomplished by passing it as either the if or else clause,
+ * with the other one being empty (PLACEHOLDER is defined as empty).
+ *
+ * The TEST_FOO parameters are for operating on different forms of input, but
+ * all should be ones that return identically for the same underlying code
+ * points */
+#define FBC_BOUND(TEST_NON_UTF8, TEST_UV, TEST_UTF8)                           \
+    FBC_BOUND_COMMON(                                                          \
+          FBC_UTF8(TEST_UV, TEST_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER),          \
+          TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
+
+#define FBC_BOUND_A(TEST_NON_UTF8, TEST_UV, TEST_UTF8)                         \
+    FBC_BOUND_COMMON(                                                          \
+            FBC_UTF8_A(TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER),           \
+            TEST_NON_UTF8, REXEC_FBC_TRYIT, PLACEHOLDER)
+
+#define FBC_NBOUND(TEST_NON_UTF8, TEST_UV, TEST_UTF8)                          \
+    FBC_BOUND_COMMON(                                                          \
+          FBC_UTF8(TEST_UV, TEST_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT),          \
+          TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
+
+#define FBC_NBOUND_A(TEST_NON_UTF8, TEST_UV, TEST_UTF8)                        \
+    FBC_BOUND_COMMON(                                                          \
+            FBC_UTF8_A(TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT),           \
+            TEST_NON_UTF8, PLACEHOLDER, REXEC_FBC_TRYIT)
+
 
 /* We know what class REx starts with.  Try to find this position... */
 /* if reginfo->intuit, its a dryrun */
 /* annoyingly all the vars in this routine have different names from their counterparts
    in regmatch. /grrr */
-
 STATIC char *
 S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s, 
     const char *strend, regmatch_info *reginfo)
@@ -1693,7 +1758,7 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
 
     case EXACTFA_NO_TRIE:   /* This node only generated for non-utf8 patterns */
         assert(! is_utf8_pat);
-       /* FALL THROUGH */
+       /* FALLTHROUGH */
     case EXACTFA:
         if (is_utf8_pat || utf8_target) {
             utf8_fold_flags = FOLDEQ_UTF8_NOMIX_ASCII;
@@ -1740,7 +1805,7 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
         fold_array = PL_fold_latin1;
         folder = foldEQ_latin1;
 
-        /* FALL THROUGH */
+        /* FALLTHROUGH */
 
     do_exactf_non_utf8: /* Neither pattern nor string are UTF8, and there
                            are no glitches with fold-length differences
@@ -1831,45 +1896,30 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
         }
         break;
     }
+
     case BOUNDL:
-        FBC_BOUND(isWORDCHAR_LC,
-                  isWORDCHAR_LC_uvchr(tmp),
-                  isWORDCHAR_LC_utf8((U8*)s));
+        FBC_BOUND(isWORDCHAR_LC, isWORDCHAR_LC_uvchr, isWORDCHAR_LC_utf8);
         break;
     case NBOUNDL:
-        FBC_NBOUND(isWORDCHAR_LC,
-                   isWORDCHAR_LC_uvchr(tmp),
-                   isWORDCHAR_LC_utf8((U8*)s));
+        FBC_NBOUND(isWORDCHAR_LC, isWORDCHAR_LC_uvchr, isWORDCHAR_LC_utf8);
         break;
     case BOUND:
-        FBC_BOUND(isWORDCHAR,
-                  isWORDCHAR_uni(tmp),
-                  cBOOL(swash_fetch(PL_utf8_swash_ptrs[_CC_WORDCHAR], (U8*)s, utf8_target)));
+        FBC_BOUND(isWORDCHAR, isWORDCHAR_uni, isWORDCHAR_utf8);
         break;
     case BOUNDA:
-        FBC_BOUND_NOLOAD(isWORDCHAR_A,
-                         isWORDCHAR_A(tmp),
-                         isWORDCHAR_A((U8*)s));
+        FBC_BOUND_A(isWORDCHAR_A, isWORDCHAR_A, isWORDCHAR_A);
         break;
     case NBOUND:
-        FBC_NBOUND(isWORDCHAR,
-                   isWORDCHAR_uni(tmp),
-                   cBOOL(swash_fetch(PL_utf8_swash_ptrs[_CC_WORDCHAR], (U8*)s, utf8_target)));
+        FBC_NBOUND(isWORDCHAR, isWORDCHAR_uni, isWORDCHAR_utf8);
         break;
     case NBOUNDA:
-        FBC_NBOUND_NOLOAD(isWORDCHAR_A,
-                          isWORDCHAR_A(tmp),
-                          isWORDCHAR_A((U8*)s));
+        FBC_NBOUND_A(isWORDCHAR_A, isWORDCHAR_A, isWORDCHAR_A);
         break;
     case BOUNDU:
-        FBC_BOUND(isWORDCHAR_L1,
-                  isWORDCHAR_uni(tmp),
-                  cBOOL(swash_fetch(PL_utf8_swash_ptrs[_CC_WORDCHAR], (U8*)s, utf8_target)));
+        FBC_BOUND(isWORDCHAR_L1, isWORDCHAR_uni, isWORDCHAR_utf8);
         break;
     case NBOUNDU:
-        FBC_NBOUND(isWORDCHAR_L1,
-                   isWORDCHAR_uni(tmp),
-                   cBOOL(swash_fetch(PL_utf8_swash_ptrs[_CC_WORDCHAR], (U8*)s, utf8_target)));
+        FBC_NBOUND(isWORDCHAR_L1, isWORDCHAR_uni, isWORDCHAR_utf8);
         break;
     case LNBREAK:
         REXEC_FBC_CSCAN(is_LNBREAK_utf8_safe(s, strend),
@@ -1902,9 +1952,8 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
     case NPOSIXA:
         if (utf8_target) {
             /* The complement of something that matches only ASCII matches all
-             * UTF-8 variant code points, plus everything in ASCII that isn't
-             * in the class */
-            REXEC_FBC_UTF8_CLASS_SCAN(! UTF8_IS_INVARIANT(*s)
+             * non-ASCII, plus everything in ASCII that isn't in the class. */
+            REXEC_FBC_UTF8_CLASS_SCAN(! isASCII_utf8(s)
                                       || ! _generic_isCC_A(*s, FLAGS(c)));
             break;
         }
@@ -1968,7 +2017,7 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
                                            macros */
                 case _CC_ENUM_SPACE: /* XXX would require separate code if we
                                         revert the change of \v matching this */
-                    /* FALL THROUGH */
+                    /* FALLTHROUGH */
 
                 case _CC_ENUM_PSXSPC:
                     REXEC_FBC_UTF8_CLASS_SCAN(
@@ -2245,7 +2294,6 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
         break;
     default:
         Perl_croak(aTHX_ "panic: unknown regstclass %d", (int)OP(c));
-        break;
     }
     return 0;
   got_it:
@@ -2420,7 +2468,6 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
 /* flags:     For optimizations. See REXEC_* in regexp.h */
 
 {
-    dVAR;
     struct regexp *const prog = ReANY(rx);
     char *s;
     regnode *c;
@@ -2442,7 +2489,6 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
     /* Be paranoid... */
     if (prog == NULL || stringarg == NULL) {
        Perl_croak(aTHX_ "NULL regexp parameter");
-       return 0;
     }
 
     DEBUG_EXECUTE_r(
@@ -2570,6 +2616,8 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
        Perl_croak(aTHX_ "corrupted regexp program");
     }
 
+    RX_MATCH_TAINTED_off(rx);
+
     reginfo->prog = rx;         /* Yes, sorry that this is confusing.  */
     reginfo->intuit = 0;
     reginfo->is_utf8_target = cBOOL(utf8_target);
@@ -2589,7 +2637,6 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
            magic belonging to this SV.
            Not newSVsv, either, as it does not COW.
         */
-        assert(!IS_PADGV(sv));
         reginfo->sv = newSV(0);
         SvSetSV_nosteal(reginfo->sv, sv);
         SAVEFREESV(reginfo->sv);
@@ -2667,7 +2714,7 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
     }
 
     /* Simplest case:  anchored match need be tried only once. */
-    /*  [unless only anchor is BOL and multiline is set] */
+    /*  [unless only anchor is MBOL - implying multiline is set] */
     if (prog->intflags & (PREGf_ANCH & ~PREGf_ANCH_GPOS)) {
        if (s == startpos && regtry(reginfo, &s))
            goto got_it;
@@ -3027,7 +3074,8 @@ Perl_regexec_flags(pTHX_ REGEXP * const rx, char *stringarg, char *strend,
                  * and replaced it with this one. Yves */
                DEBUG_EXECUTE_r(
                    PerlIO_printf(Perl_debug_log,
-                       "String does not contain required substring, cannot match.\n"
+                       "%sString does not contain required substring, cannot match.%s\n",
+                        PL_colors[4], PL_colors[5]
                    ));
                goto phooey;
            }
@@ -3140,7 +3188,6 @@ phooey:
 STATIC I32                     /* 0 failure, 1 success */
 S_regtry(pTHX_ regmatch_info *reginfo, char **startposp)
 {
-    dVAR;
     CHECKPOINT lastcp;
     REGEXP *const rx = reginfo->prog;
     regexp *const prog = ReANY(rx);
@@ -3511,7 +3558,7 @@ S_dump_exec_pos(pTHX_ const char *locinput,
  * or 0 if non of the buffers matched.
  */
 STATIC I32
-S_reg_check_named_buff_matched(pTHX_ const regexp *rex, const regnode *scan)
+S_reg_check_named_buff_matched(const regexp *rex, const regnode *scan)
 {
     I32 n;
     RXi_GET_DECL(rex,rexi);
@@ -3587,8 +3634,8 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
 
     const bool utf8_target = reginfo->is_utf8_target;
 
-    UV c1 = CHRTEST_NOT_A_CP_1;
-    UV c2 = CHRTEST_NOT_A_CP_2;
+    UV c1 = (UV)CHRTEST_NOT_A_CP_1;
+    UV c2 = (UV)CHRTEST_NOT_A_CP_2;
     bool use_chrtest_void = FALSE;
     const bool is_utf8_pat = reginfo->is_utf8_pat;
 
@@ -3679,18 +3726,11 @@ 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 > 256) {
+            if (c1 > 255) {
                 /* Load the folds hash, if not already done */
                 SV** listp;
                 if (! PL_utf8_foldclosures) {
-                    if (! PL_utf8_tofold) {
-                        U8 dummy[UTF8_MAXBYTES_CASE+1];
-
-                        /* Force loading this by folding an above-Latin1 char */
-                        to_utf8_fold((U8*) HYPHEN_UTF8, dummy, NULL);
-                        assert(PL_utf8_tofold); /* Verify that worked */
-                    }
-                    PL_utf8_foldclosures = _swash_inversion_hash(PL_utf8_tofold);
+                    _load_PL_utf8_foldclosures();
                 }
 
                 /* The fold closures data structure is a hash with the keys
@@ -3732,10 +3772,10 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
                         /* 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
-                         * 256, and its only other match is below 256, the only
+                         * 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 */
+                         * above 255. */
                         if ((c1 < 256) != (c2 < 256)) {
                             if ((OP(text_node) == EXACTFL
                                  && ! IN_UTF8_CTYPE_LOCALE)
@@ -3754,7 +3794,7 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
                     }
                 }
             }
-            else /* Here, c1 is < 255 */
+            else /* Here, c1 is <= 255 */
                 if (utf8_target
                     && HAS_NONLATIN1_FOLD_CLOSURE(c1)
                     && ( ! (OP(text_node) == EXACTFL && ! IN_UTF8_CTYPE_LOCALE))
@@ -3795,7 +3835,7 @@ S_setup_EXACTISH_ST_c1_c2(pTHX_ const regnode * const text_node, int *c1p,
                     case EXACTFA_NO_TRIE:   /* This node only generated for
                                             non-utf8 patterns */
                         assert(! is_utf8_pat);
-                        /* FALL THROUGH */
+                        /* FALLTHROUGH */
                     case EXACTFA:
                     case EXACTFU_SS:
                     case EXACTFU:
@@ -3973,8 +4013,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
         assert(nextchr < 256 && (nextchr >= 0 || nextchr == NEXTCHR_EOS));
 
        switch (state_num) {
-       case BOL:  /*  /^../   */
-       case SBOL: /*  /^../s  */
+       case SBOL: /*  /^../ and /\A../  */
            if (locinput == reginfo->strbeg)
                break;
            sayNO;
@@ -3997,21 +4036,22 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
            st->u.keeper.val = rex->offs[0].start;
            rex->offs[0].start = locinput - reginfo->strbeg;
            PUSH_STATE_GOTO(KEEPS_next, next, locinput);
-           assert(0); /*NOTREACHED*/
+            /* NOTREACHED */
+           assert(0);
+
        case KEEPS_next_fail:
            /* rollback the start point change */
            rex->offs[0].start = st->u.keeper.val;
            sayNO_SILENT;
-           assert(0); /*NOTREACHED*/
+            /* NOTREACHED */
+           assert(0);
 
        case MEOL: /* /..$/m  */
            if (!NEXTCHR_IS_EOS && nextchr != '\n')
                sayNO;
            break;
 
-       case EOL: /* /..$/  */
-            /* FALL THROUGH */
-       case SEOL: /* /..$/s  */
+       case SEOL: /* /..$/  */
            if (!NEXTCHR_IS_EOS && nextchr != '\n')
                sayNO;
            if (reginfo->strend - locinput > 1)
@@ -4053,9 +4093,10 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                               REPORT_CODE_OFF+depth*2, "", PL_colors[4], PL_colors[5])
                 );
                 sayNO_SILENT;
-                assert(0); /* NOTREACHED */
+                /* NOTREACHED */
+                assert(0);
             }
-            /* FALL THROUGH */
+            /* FALLTHROUGH */
        case TRIE:  /* (ab|cd)  */
            /* the basic plan of execution of the trie is:
             * At the beginning, run though all the states, and
@@ -4240,7 +4281,8 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                );
                goto trie_first_try; /* jump into the fail handler */
            }}
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case TRIE_next_fail: /* we failed - try next alternative */
         {
@@ -4354,7 +4396,8 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
 
            if (ST.accepted > 1 || has_cutgroup) {
                PUSH_STATE_GOTO(TRIE_next, scan, (char*)uc);
-               assert(0); /* NOTREACHED */
+                /* NOTREACHED */
+               assert(0);
            }
            /* only one choice left - just continue */
            DEBUG_EXECUTE_r({
@@ -4378,7 +4421,8 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
 
            locinput = (char*)uc;
            continue; /* execute rest of RE */
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
         }
 #undef  ST
 
@@ -4483,7 +4527,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
         case EXACTFA_NO_TRIE:   /* This node only generated for non-utf8
                                    patterns */
             assert(! is_utf8_pat);
-            /* FALL THROUGH */
+            /* FALLTHROUGH */
        case EXACTFA:            /*  /abc/iaa     */
            folder = foldEQ_latin1;
            fold_array = PL_fold_latin1;
@@ -4610,7 +4654,6 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                        break;
                    default:
                        Perl_croak(aTHX_ "panic: Unexpected FLAGS %u in op %u", FLAGS(scan), OP(scan));
-                       break;
                }
            }
            /* Note requires that all BOUNDs be lower than all NBOUNDs in
@@ -5146,9 +5189,6 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
        case TAIL: /* placeholder while compiling (A|B|C) */
            break;
 
-       case BACK: /* ??? doesn't appear to be used ??? */
-           break;
-
 #undef  ST
 #define ST st->u.eval
        {
@@ -5188,7 +5228,8 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
             /* and then jump to the code we share with EVAL */
             goto eval_recurse_doit;
 
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
         case EVAL:  /*   /(?{A})B/   /(??{A})B/  and /(?(?{A})X|Y)B/   */        
             if (cur_eval && cur_eval->locinput==locinput) {
@@ -5277,7 +5318,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                        assert(o->op_targ == OP_LEAVE);
                        o = cUNOPo->op_first;
                        assert(o->op_type == OP_ENTER);
-                       o = o->op_sibling;
+                       o = OP_SIBLING(o);
                    }
 
                    if (o->op_type != OP_STUB) {
@@ -5404,7 +5445,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                        re_sv = rex->engine->op_comp(aTHX_ &ret, 1, NULL,
                                    rex->engine, NULL, NULL,
                                     /* copy /msix etc to inner pattern */
-                                    scan->flags,
+                                    ARG2L(scan),
                                     pm_flags);
 
                        if (!(SvFLAGS(ret)
@@ -5469,7 +5510,8 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                cur_eval = st;
                /* now continue from first node in postoned RE */
                PUSH_YES_STATE_GOTO(EVAL_AB, startpoint, locinput);
-               assert(0); /* NOTREACHED */
+                /* NOTREACHED */
+               assert(0);
        }
 
        case EVAL_AB: /* cleanup after a successful (??{A})B */
@@ -5578,7 +5620,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, char *startpos, regnode *prog)
                 }
             }
            goto fake_end;
-           /*NOTREACHED*/          
+           /* NOTREACHED */
 
        case GROUPP:  /*  (?(1))  */
            n = ARG(scan);  /* which paren pair */
@@ -5728,19 +5770,22 @@ NULL
            ST.lastloc = NULL;  /* this will be updated by WHILEM */
 
            PUSH_YES_STATE_GOTO(CURLYX_end, PREVOPER(next), locinput);
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
        }
 
        case CURLYX_end: /* just finished matching all of A*B */
            cur_curlyx = ST.prev_curlyx;
            sayYES;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case CURLYX_end_fail: /* just failed to match all of A*B */
            regcpblow(ST.cp);
            cur_curlyx = ST.prev_curlyx;
            sayNO;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
 
 #undef ST
@@ -5750,11 +5795,14 @@ NULL
        {
            /* see the discussion above about CURLYX/WHILEM */
            I32 n;
-           int min = ARG1(cur_curlyx->u.curlyx.me);
-           int max = ARG2(cur_curlyx->u.curlyx.me);
-           regnode *A = NEXTOPER(cur_curlyx->u.curlyx.me) + EXTRA_STEP_2ARGS;
+           int min, max;
+           regnode *A;
 
            assert(cur_curlyx); /* keep Coverity happy */
+
+           min = ARG1(cur_curlyx->u.curlyx.me);
+           max = ARG2(cur_curlyx->u.curlyx.me);
+           A = NEXTOPER(cur_curlyx->u.curlyx.me) + EXTRA_STEP_2ARGS;
            n = ++cur_curlyx->u.curlyx.count; /* how many A's matched */
            ST.save_lastloc = cur_curlyx->u.curlyx.lastloc;
            ST.cache_offset = 0;
@@ -5775,7 +5823,8 @@ NULL
                REGCP_SET(ST.lastcp);
 
                PUSH_STATE_GOTO(WHILEM_A_pre, A, locinput);
-               assert(0); /* NOTREACHED */
+                /* NOTREACHED */
+               assert(0);
            }
 
            /* If degenerate A matches "", assume A done. */
@@ -5887,7 +5936,8 @@ NULL
                REGCP_SET(ST.lastcp);
                PUSH_YES_STATE_GOTO(WHILEM_B_min, ST.save_curlyx->u.curlyx.B,
                                     locinput);
-               assert(0); /* NOTREACHED */
+                /* NOTREACHED */
+               assert(0);
            }
 
            /* Prefer A over B for maximal matching. */
@@ -5898,34 +5948,39 @@ NULL
                cur_curlyx->u.curlyx.lastloc = locinput;
                REGCP_SET(ST.lastcp);
                PUSH_STATE_GOTO(WHILEM_A_max, A, locinput);
-               assert(0); /* NOTREACHED */
+                /* NOTREACHED */
+               assert(0);
            }
            goto do_whilem_B_max;
        }
-       assert(0); /* NOTREACHED */
+        /* NOTREACHED */
+       assert(0);
 
        case WHILEM_B_min: /* just matched B in a minimal match */
        case WHILEM_B_max: /* just matched B in a maximal match */
            cur_curlyx = ST.save_curlyx;
            sayYES;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case WHILEM_B_max_fail: /* just failed to match B in a maximal match */
            cur_curlyx = ST.save_curlyx;
            cur_curlyx->u.curlyx.lastloc = ST.save_lastloc;
            cur_curlyx->u.curlyx.count--;
            CACHEsayNO;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case WHILEM_A_min_fail: /* just failed to match A in a minimal match */
-           /* FALL THROUGH */
+           /* FALLTHROUGH */
        case WHILEM_A_pre_fail: /* just failed to match even minimal A */
            REGCP_UNWIND(ST.lastcp);
            regcppop(rex, &maxopenparen);
            cur_curlyx->u.curlyx.lastloc = ST.save_lastloc;
            cur_curlyx->u.curlyx.count--;
            CACHEsayNO;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case WHILEM_A_max_fail: /* just failed to match A in a maximal match */
            REGCP_UNWIND(ST.lastcp);
@@ -5951,7 +6006,8 @@ NULL
            cur_curlyx = cur_curlyx->u.curlyx.prev_curlyx;
            PUSH_YES_STATE_GOTO(WHILEM_B_max, ST.save_curlyx->u.curlyx.B,
                                 locinput);
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case WHILEM_B_min_fail: /* just failed to match B in a minimal match */
            cur_curlyx = ST.save_curlyx;
@@ -5985,7 +6041,8 @@ NULL
            PUSH_STATE_GOTO(WHILEM_A_min,
                /*A*/ NEXTOPER(ST.save_curlyx->u.curlyx.me) + EXTRA_STEP_2ARGS,
                 locinput);
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
 #undef  ST
 #define ST st->u.branch
@@ -5995,7 +6052,7 @@ NULL
            if (next == scan)
                next = NULL;
            scan = NEXTOPER(scan);
-           /* FALL THROUGH */
+           /* FALLTHROUGH */
 
        case BRANCH:        /*  /(...|A|...)/ */
            scan = NEXTOPER(scan); /* scan now points to inner node */
@@ -6010,13 +6067,15 @@ NULL
            } else {
                PUSH_STATE_GOTO(BRANCH_next, scan, locinput);
            }
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
         case CUTGROUP:  /*  /(*THEN)/  */
             sv_yes_mark = st->u.mark.mark_name = scan->flags ? NULL :
                 MUTABLE_SV(rexi->data->data[ ARG( scan ) ]);
             PUSH_STATE_GOTO(CUTGROUP_next, next, locinput);
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
         case CUTGROUP_next_fail:
             do_cutgroup = 1;
@@ -6024,11 +6083,13 @@ NULL
             if (st->u.mark.mark_name)
                 sv_commit = st->u.mark.mark_name;
             sayNO;         
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
         case BRANCH_next:
             sayYES;
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
        case BRANCH_next_fail: /* that branch failed; try the next, if any */
            if (do_cutgroup) {
@@ -6050,7 +6111,8 @@ NULL
                sayNO_SILENT;
             }
            continue; /* execute next BRANCH[J] op */
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
     
        case MINMOD: /* next op will be non-greedy, e.g. A*?  */
            minmod = 1;
@@ -6094,7 +6156,8 @@ NULL
 
          curlym_do_A: /* execute the A in /A{m,n}B/  */
            PUSH_YES_STATE_GOTO(CURLYM_A, ST.A, locinput); /* match A */
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case CURLYM_A: /* we've just matched an A */
            ST.count++;
@@ -6144,6 +6207,7 @@ NULL
                /* calculate c1 and c2 for possible match of 1st char
                 * following curly */
                ST.c1 = ST.c2 = CHRTEST_VOID;
+                assert(ST.B);
                if (HAS_TEXT(ST.B) || JUMPABLE(ST.B)) {
                    regnode *text_node = ST.B;
                    if (! HAS_TEXT(text_node))
@@ -6229,7 +6293,8 @@ NULL
            }
            
            PUSH_STATE_GOTO(CURLYM_B, ST.B, locinput); /* match B */
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case CURLYM_B_fail: /* just failed to match a B */
            REGCP_UNWIND(ST.cp);
@@ -6407,8 +6472,8 @@ NULL
                REGCP_SET(ST.cp);
                goto curly_try_B_max;
            }
-           assert(0); /* NOTREACHED */
-
+            /* NOTREACHED */
+           assert(0);
 
        case CURLY_B_min_known_fail:
            /* failed to find B in a non-greedy match where c1,c2 valid */
@@ -6483,8 +6548,8 @@ NULL
                }
                PUSH_STATE_GOTO(CURLY_B_min_known, ST.B, locinput);
            }
-           assert(0); /* NOTREACHED */
-
+            /* NOTREACHED */
+           assert(0);
 
        case CURLY_B_min_fail:
            /* failed to find B in a non-greedy match where c1,c2 invalid */
@@ -6516,8 +6581,8 @@ NULL
                }
            }
             sayNO;
-           assert(0); /* NOTREACHED */
-
+            /* NOTREACHED */
+           assert(0);
 
        curly_try_B_max:
            /* a successful greedy match: now try to match B */
@@ -6547,10 +6612,11 @@ NULL
                 if (ST.c1 == CHRTEST_VOID || could_match) {
                    CURLY_SETPAREN(ST.paren, ST.count);
                    PUSH_STATE_GOTO(CURLY_B_max, ST.B, locinput);
-                   assert(0); /* NOTREACHED */
+                    /* NOTREACHED */
+                   assert(0);
                }
            }
-           /* FALL THROUGH */
+           /* FALLTHROUGH */
 
        case CURLY_B_max_fail:
            /* failed to find B in a greedy match */
@@ -6666,12 +6732,13 @@ NULL
            
            /* execute body of (?...A) */
            PUSH_YES_STATE_GOTO(IFMATCH_A, NEXTOPER(NEXTOPER(scan)), newstart);
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
         }
 
        case IFMATCH_A_fail: /* body of (?...A) failed */
            ST.wanted = !ST.wanted;
-           /* FALL THROUGH */
+           /* FALLTHROUGH */
 
        case IFMATCH_A: /* body of (?...A) succeeded */
            if (ST.logical) {
@@ -6706,7 +6773,8 @@ NULL
            if (!scan->flags)
                sv_yes_mark = sv_commit = MUTABLE_SV(rexi->data->data[ ARG( scan ) ]);
            PUSH_STATE_GOTO(COMMIT_next, next, locinput);
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
        case COMMIT_next_fail:
            no_final = 1;    
@@ -6714,7 +6782,8 @@ NULL
 
        case OPFAIL:   /* (*FAIL)  */
            sayNO;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
 
 #define ST st->u.mark
         case MARKPOINT: /*  (*MARK:foo)  */
@@ -6724,12 +6793,14 @@ NULL
             mark_state = st;
             ST.mark_loc = locinput;
             PUSH_YES_STATE_GOTO(MARKPOINT_next, next, locinput);
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
         case MARKPOINT_next:
             mark_state = ST.prev_mark;
             sayYES;
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
         case MARKPOINT_next_fail:
             if (popmark && sv_eq(ST.mark_name,popmark)) 
@@ -6750,7 +6821,8 @@ NULL
             sv_yes_mark = mark_state ? 
                 mark_state->u.mark.mark_name : NULL;
             sayNO;
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 
         case SKIP:  /*  (*SKIP)  */
             if (scan->flags) {
@@ -6795,7 +6867,8 @@ NULL
             } 
             no_final = 1; 
             sayNO;
-            assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+            assert(0);
 #undef ST
 
         case LNBREAK: /* \R */
@@ -6829,13 +6902,14 @@ NULL
         /* switch break jumps here */
        scan = next; /* prepare to execute the next op and ... */
        continue;    /* ... jump back to the top, reusing st */
-       assert(0); /* NOTREACHED */
+        /* NOTREACHED */
+       assert(0);
 
       push_yes_state:
        /* push a state that backtracks on success */
        st->u.yes.prev_yes_state = yes_state;
        yes_state = st;
-       /* FALL THROUGH */
+       /* FALLTHROUGH */
       push_state:
        /* push a new regex state, then continue at scan  */
        {
@@ -6872,7 +6946,8 @@ NULL
            locinput = pushinput;
            st = newst;
            continue;
-           assert(0); /* NOTREACHED */
+            /* NOTREACHED */
+           assert(0);
        }
     }
 
@@ -6881,7 +6956,7 @@ NULL
     * the terminating point.
     */
     Perl_croak(aTHX_ "corrupted regexp pointers");
-    /*NOTREACHED*/
+    /* NOTREACHED */
     sayNO;
 
 yes:
@@ -6994,6 +7069,8 @@ no_silent:
                 sv_commit = &PL_sv_yes;
             sv_yes_mark = &PL_sv_no;
         }
+        assert(sv_err);
+        assert(sv_mrk);
         sv_setsv(sv_err, sv_commit);
         sv_setsv(sv_mrk, sv_yes_mark);
     }
@@ -7027,7 +7104,6 @@ STATIC I32
 S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
             regmatch_info *const reginfo, I32 max, int depth)
 {
-    dVAR;
     char *scan;     /* Pointer to current position in target string */
     I32 c;
     char *loceol = reginfo->strend;   /* local version */
@@ -7170,7 +7246,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
 
     case EXACTFA_NO_TRIE:   /* This node only generated for non-utf8 patterns */
         assert(! reginfo->is_utf8_pat);
-        /* FALL THROUGH */
+        /* FALLTHROUGH */
     case EXACTFA:
         utf8_flags = FOLDEQ_UTF8_NOMIX_ASCII;
        goto do_exactf;
@@ -7310,7 +7386,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
             to_complement = 1;
             goto utf8_posix;
         }
-        /* FALL THROUGH */
+        /* FALLTHROUGH */
 
     case NPOSIXA:
         if (! utf8_target) {
@@ -7321,10 +7397,9 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
         else {
 
             /* The complement of something that matches only ASCII matches all
-             * UTF-8 variant code points, plus everything in ASCII that isn't
-             * in the class. */
+             * non-ASCII, plus everything in ASCII that isn't in the class. */
            while (hardcount < max && scan < loceol
-                   && (! UTF8_IS_INVARIANT(*scan)
+                   && (! isASCII_utf8(scan)
                        || ! _generic_isCC_A((U8) *scan, FLAGS(p))))
             {
                 scan += UTF8SKIP(scan);
@@ -7392,7 +7467,7 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
                     case _CC_ENUM_SPACE:    /* XXX would require separate code
                                                if we revert the change of \v
                                                matching this */
-                        /* FALL THROUGH */
+                        /* FALLTHROUGH */
                     case _CC_ENUM_PSXSPC:
                         while (hardcount < max
                                && scan < loceol
@@ -7508,7 +7583,8 @@ S_regrepeat(pTHX_ regexp *prog, char **startposp, const regnode *p,
 
     default:
         Perl_croak(aTHX_ "panic: regrepeat() called with unrecognized node type %d='%s'", OP(p), PL_reg_name[OP(p)]);
-        assert(0); /* NOTREACHED */
+        /* NOTREACHED */
+        assert(0);
 
     }
 
@@ -7548,121 +7624,9 @@ Perl_regclass_swash(pTHX_ const regexp *prog, const regnode* node, bool doinit,
         *altsvp = NULL;
     }
 
-    return newSVsv(_get_regclass_nonbitmap_data(prog, node, doinit, listsvp, NULL));
+    return newSVsv(_get_regclass_nonbitmap_data(prog, node, doinit, listsvp, NULL, NULL));
 }
 
-SV *
-Perl__get_regclass_nonbitmap_data(pTHX_ const regexp *prog,
-                                        const regnode* node,
-                                        bool doinit,
-                                        SV** listsvp,
-                                        SV** only_utf8_locale_ptr)
-{
-    /* For internal core use only.
-     * Returns the swash for the input 'node' in the regex 'prog'.
-     * If <doinit> is 'true', will attempt to create the swash if not already
-     *   done.
-     * If <listsvp> is non-null, will return the printable contents of the
-     *    swash.  This can be used to get debugging information even before the
-     *    swash exists, by calling this function with 'doinit' set to false, in
-     *    which case the components that will be used to eventually create the
-     *    swash are returned  (in a printable form).
-     * Tied intimately to how regcomp.c sets up the data structure */
-
-    dVAR;
-    SV *sw  = NULL;
-    SV *si  = NULL;         /* Input swash initialization string */
-    SV*  invlist = NULL;
-
-    RXi_GET_DECL(prog,progi);
-    const struct reg_data * const data = prog ? progi->data : NULL;
-
-    PERL_ARGS_ASSERT__GET_REGCLASS_NONBITMAP_DATA;
-
-    assert(ANYOF_FLAGS(node)
-                        & (ANYOF_UTF8|ANYOF_NONBITMAP_NON_UTF8|ANYOF_LOC_FOLD));
-
-    if (data && data->count) {
-       const U32 n = ARG(node);
-
-       if (data->what[n] == 's') {
-           SV * const rv = MUTABLE_SV(data->data[n]);
-           AV * const av = MUTABLE_AV(SvRV(rv));
-           SV **const ary = AvARRAY(av);
-           U8 swash_init_flags = _CORE_SWASH_INIT_ACCEPT_INVLIST;
-       
-           si = *ary;  /* ary[0] = the string to initialize the swash with */
-
-           /* Elements 3 and 4 are either both present or both absent. [3] is
-            * any inversion list generated at compile time; [4] indicates if
-            * that inversion list has any user-defined properties in it. */
-            if (av_tindex(av) >= 2) {
-                if (only_utf8_locale_ptr
-                    && ary[2]
-                    && ary[2] != &PL_sv_undef)
-                {
-                    *only_utf8_locale_ptr = ary[2];
-                }
-                else {
-                    *only_utf8_locale_ptr = NULL;
-                }
-
-                if (av_tindex(av) >= 3) {
-                    invlist = ary[3];
-                    if (SvUV(ary[4])) {
-                        swash_init_flags |= _CORE_SWASH_INIT_USER_DEFINED_PROPERTY;
-                    }
-                }
-                else {
-                    invlist = NULL;
-                }
-           }
-
-           /* Element [1] is reserved for the set-up swash.  If already there,
-            * return it; if not, create it and store it there */
-           if (ary[1] && SvROK(ary[1])) {
-               sw = ary[1];
-           }
-           else if (doinit && ((si && si != &PL_sv_undef)
-                                 || (invlist && invlist != &PL_sv_undef))) {
-
-               sw = _core_swash_init("utf8", /* the utf8 package */
-                                     "", /* nameless */
-                                     si,
-                                     1, /* binary */
-                                     0, /* not from tr/// */
-                                     invlist,
-                                     &swash_init_flags);
-               (void)av_store(av, 1, sw);
-           }
-       }
-    }
-       
-    /* If requested, return a printable version of what this swash matches */
-    if (listsvp) {
-       SV* matches_string = newSVpvn("", 0);
-
-        /* The swash should be used, if possible, to get the data, as it
-         * contains the resolved data.  But this function can be called at
-         * compile-time, before everything gets resolved, in which case we
-         * return the currently best available information, which is the string
-         * that will eventually be used to do that resolving, 'si' */
-       if ((! sw || (invlist = _get_swash_invlist(sw)) == NULL)
-            && (si && si != &PL_sv_undef))
-        {
-           sv_catsv(matches_string, si);
-       }
-
-       /* Add the inversion list to whatever we have.  This may have come from
-        * the swash, or from an input parameter */
-       if (invlist) {
-           sv_catsv(matches_string, _invlist_contents(invlist));
-       }
-       *listsvp = matches_string;
-    }
-
-    return sw;
-}
 #endif /* !defined(PERL_IN_XSUB_RE) || defined(PLUGGABLE_RE_EXTENSION) */
 
 /*
@@ -7705,22 +7669,25 @@ S_reginclass(pTHX_ regexp * const prog, const regnode * const n, const U8* const
     }
 
     /* If this character is potentially in the bitmap, check it */
-    if (c < 256) {
+    if (c < NUM_ANYOF_CODE_POINTS) {
        if (ANYOF_BITMAP_TEST(n, c))
            match = TRUE;
-       else if (flags & ANYOF_NON_UTF8_NON_ASCII_ALL
-               && ! utf8_target
-               && ! isASCII(c))
+       else if ((flags & ANYOF_MATCHES_ALL_NON_UTF8_NON_ASCII)
+                 && ! utf8_target
+                 && ! isASCII(c))
        {
            match = TRUE;
        }
        else if (flags & ANYOF_LOCALE_FLAGS) {
-           if (flags & ANYOF_LOC_FOLD) {
-                if (ANYOF_BITMAP_TEST(n, PL_fold_locale[c])) {
-                    match = TRUE;
-                }
+           if ((flags & ANYOF_LOC_FOLD)
+                && c < 256
+               && ANYOF_BITMAP_TEST(n, PL_fold_locale[c]))
+            {
+                match = TRUE;
             }
-           if (! match && ANYOF_POSIXL_TEST_ANY_SET(n)) {
+            else if (ANYOF_POSIXL_TEST_ANY_SET(n)
+                     && c < 256
+            ) {
 
                 /* The data structure is arranged so bits 0, 2, 4, ... are set
                  * if the class includes the Posix character class given by
@@ -7773,33 +7740,34 @@ S_reginclass(pTHX_ regexp * const prog, const regnode * const n, const U8* const
     /* If the bitmap didn't (or couldn't) match, and something outside the
      * bitmap could match, try that. */
     if (!match) {
-       if (c >= 256 && (flags & ANYOF_ABOVE_LATIN1_ALL)) {
-           match = TRUE;       /* Everything above 255 matches */
+       if (c >= NUM_ANYOF_CODE_POINTS
+            && (flags & ANYOF_MATCHES_ALL_ABOVE_BITMAP))
+        {
+           match = TRUE;       /* Everything above the bitmap matches */
        }
-       else if ((flags & ANYOF_NONBITMAP_NON_UTF8)
-                 || (utf8_target && (flags & ANYOF_UTF8))
+       else if ((flags & ANYOF_HAS_NONBITMAP_NON_UTF8_MATCHES)
+                 || (utf8_target && (flags & ANYOF_HAS_UTF8_NONBITMAP_MATCHES))
                   || ((flags & ANYOF_LOC_FOLD)
                        && IN_UTF8_CTYPE_LOCALE
-                       && ARG(n) != ANYOF_NONBITMAP_EMPTY))
+                       && ARG(n) != ANYOF_ONLY_HAS_BITMAP))
         {
             SV* only_utf8_locale = NULL;
            SV * const sw = _get_regclass_nonbitmap_data(prog, n, TRUE, 0,
-                                                            &only_utf8_locale);
+                                                       &only_utf8_locale, NULL);
            if (sw) {
+                U8 utf8_buffer[2];
                U8 * utf8_p;
                if (utf8_target) {
                    utf8_p = (U8 *) p;
                } else { /* Convert to utf8 */
-                   STRLEN len = 1;
-                   utf8_p = bytes_to_utf8(p, &len);
+                   utf8_p = utf8_buffer;
+                    append_utf8_from_native_byte(*p, &utf8_p);
+                   utf8_p = utf8_buffer;
                }
 
                if (swash_fetch(sw, utf8_p, TRUE)) {
                    match = TRUE;
                 }
-
-               /* If we allocated a string above, free it */
-               if (! utf8_target) Safefree(utf8_p);
            }
             if (! match && only_utf8_locale && IN_UTF8_CTYPE_LOCALE) {
                 match = _invlist_contains_cp(only_utf8_locale, c);
@@ -7832,8 +7800,6 @@ S_reghop3(U8 *s, SSize_t off, const U8* lim)
      * 'off' >= 0, backwards if negative.  But don't go outside of position
      * 'lim', which better be < s  if off < 0 */
 
-    dVAR;
-
     PERL_ARGS_ASSERT_REGHOP3;
 
     if (off >= 0) {
@@ -7858,8 +7824,6 @@ S_reghop3(U8 *s, SSize_t off, const U8* lim)
 STATIC U8 *
 S_reghop4(U8 *s, SSize_t off, const U8* llim, const U8* rlim)
 {
-    dVAR;
-
     PERL_ARGS_ASSERT_REGHOP4;
 
     if (off >= 0) {
@@ -7887,8 +7851,6 @@ S_reghop4(U8 *s, SSize_t off, const U8* llim, const U8* rlim)
 STATIC U8 *
 S_reghopmaybe3(U8* s, SSize_t off, const U8* lim)
 {
-    dVAR;
-
     PERL_ARGS_ASSERT_REGHOPMAYBE3;
 
     if (off >= 0) {
@@ -8005,7 +7967,6 @@ S_setup_eval_state(pTHX_ regmatch_info *const reginfo)
 static void
 S_cleanup_regmatch_info_aux(pTHX_ void *arg)
 {
-    dVAR;
     regmatch_info_aux *aux = (regmatch_info_aux *) arg;
     regmatch_info_aux_eval *eval_state =  aux->info_aux_eval;
     regmatch_slab *s;
@@ -8097,7 +8058,6 @@ S_to_byte_substr(pTHX_ regexp *prog)
     /* Converts substr fields in prog from UTF-8 to bytes, calling fbm_compile
      * on the converted value; returns FALSE if can't be converted. */
 
-    dVAR;
     int i = 1;
 
     PERL_ARGS_ASSERT_TO_BYTE_SUBSTR;