Re: [PATCH regexec.c] lookahead for REF, MINMOD, PLUS, CURLY*
Jeff Pinyan [Wed, 14 Nov 2001 09:59:31 +0000 (04:59 -0500)]
Message-ID: <Pine.GSO.4.21.0111140958390.1124-100000@crusoe.crusoe.net>

p4raw-id: //depot/perl@13002

regexec.c

index 712c4d9..4904e57 100644 (file)
--- a/regexec.c
+++ b/regexec.c
 /* for use after a quantifier and before an EXACT-like node -- japhy */
 #define JUMPABLE(rn) ( \
     OP(rn) == OPEN || OP(rn) == CLOSE || OP(rn) == EVAL || \
-    OP(rn) == SUSPEND || OP(rn) == IFMATCH \
+    OP(rn) == SUSPEND || OP(rn) == IFMATCH || \
+    OP(rn) == PLUS || OP(rn) == MINMOD || \
+    (PL_regkind[(U8)OP(rn)] == CURLY && ARG1(rn) > 0) \
 )
 
-#define NEAR_EXACT(rn) (PL_regkind[(U8)OP(rn)] == EXACT || JUMPABLE(rn))
+#define HAS_TEXT(rn) ( \
+    PL_regkind[(U8)OP(rn)] == EXACT || PL_regkind[(U8)OP(rn)] == REF \
+)
 
-#define NEXT_IMPT(rn) STMT_START { \
+#define FIND_NEXT_IMPT(rn) STMT_START { \
     while (JUMPABLE(rn)) \
-       if (OP(rn) == SUSPEND || OP(rn) == IFMATCH) \
+       if (OP(rn) == SUSPEND || OP(rn) == IFMATCH || \
+           PL_regkind[(U8)OP(rn)] == CURLY) \
            rn = NEXTOPER(NEXTOPER(rn)); \
+       else if (OP(rn) == PLUS) \
+           rn = NEXTOPER(rn); \
        else rn += NEXT_OFF(rn); \
 } STMT_END 
 
@@ -3113,17 +3120,29 @@ S_regmatch(pTHX_ regnode *prog)
                if (ln && l == 0)
                    n = ln;     /* don't backtrack */
                locinput = PL_reginput;
-               if (NEAR_EXACT(next)) {
+               if (HAS_TEXT(next) || JUMPABLE(next)) {
                    regnode *text_node = next;
 
-                   if (PL_regkind[(U8)OP(next)] != EXACT)
-                       NEXT_IMPT(text_node);
+                   if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 
-                   if (PL_regkind[(U8)OP(text_node)] != EXACT) {
-                       c1 = c2 = -1000;
-                   }
+                   if (! HAS_TEXT(text_node)) c1 = c2 = -1000;
                    else {
-                       c1 = (U8)*STRING(text_node);
+                       if (PL_regkind[(U8)OP(text_node)] == REF) {
+                           I32 n, ln;
+                           n = ARG(text_node);  /* which paren pair */
+                           ln = PL_regstartp[n];
+                           /* assume yes if we haven't seen CLOSEn */
+                           if (
+                               *PL_reglastparen < n ||
+                               ln == -1 ||
+                               ln == PL_regendp[n]
+                           ) {
+                               c1 = c2 = -1000;
+                               goto assume_ok_MM;
+                           }
+                           c1 = *(PL_bostr + ln);
+                       }
+                       else { c1 = (U8)*STRING(text_node); }
                        if (OP(next) == EXACTF)
                            c2 = PL_fold[c1];
                        else if (OP(text_node) == EXACTFL)
@@ -3134,6 +3153,7 @@ S_regmatch(pTHX_ regnode *prog)
                }
                else
                    c1 = c2 = -1000;
+           assume_ok_MM:
                REGCP_SET(lastcp);
                /* This may be improved if l == 0.  */
                while (n >= ln || (n == REG_INFTY && ln > 0 && l)) { /* ln overflow ? */
@@ -3182,17 +3202,30 @@ S_regmatch(pTHX_ regnode *prog)
                                  (IV) n, (IV)l)
                    );
                if (n >= ln) {
-                   if (NEAR_EXACT(next)) {
+                   if (HAS_TEXT(next) || JUMPABLE(next)) {
                        regnode *text_node = next;
 
-                       if (PL_regkind[(U8)OP(next)] != EXACT)
-                           NEXT_IMPT(text_node);
+                       if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 
-                       if (PL_regkind[(U8)OP(text_node)] != EXACT) {
-                           c1 = c2 = -1000;
-                       }
+                       if (! HAS_TEXT(text_node)) c1 = c2 = -1000;
                        else {
-                           c1 = (U8)*STRING(text_node);
+                           if (PL_regkind[(U8)OP(text_node)] == REF) {
+                               I32 n, ln;
+                               n = ARG(text_node);  /* which paren pair */
+                               ln = PL_regstartp[n];
+                               /* assume yes if we haven't seen CLOSEn */
+                               if (
+                                   *PL_reglastparen < n ||
+                                   ln == -1 ||
+                                   ln == PL_regendp[n]
+                               ) {
+                                   c1 = c2 = -1000;
+                                   goto assume_ok_REG;
+                               }
+                               c1 = *(PL_bostr + ln);
+                           }
+                           else { c1 = (U8)*STRING(text_node); }
+
                            if (OP(text_node) == EXACTF)
                                c2 = PL_fold[c1];
                            else if (OP(text_node) == EXACTFL)
@@ -3204,6 +3237,7 @@ S_regmatch(pTHX_ regnode *prog)
                    else
                        c1 = c2 = -1000;
                }
+           assume_ok_REG:
                REGCP_SET(lastcp);
                while (n >= ln) {
                    /* If it could work, try it. */
@@ -3276,18 +3310,30 @@ S_regmatch(pTHX_ regnode *prog)
            * of the quantifier and the EXACT-like node.  -- japhy
            */
 
-           if (NEAR_EXACT(next)) {
+           if (HAS_TEXT(next) || JUMPABLE(next)) {
                U8 *s;
                regnode *text_node = next;
 
-               if (PL_regkind[(U8)OP(next)] != EXACT)
-                   NEXT_IMPT(text_node);
+               if (! HAS_TEXT(text_node)) FIND_NEXT_IMPT(text_node);
 
-               if (PL_regkind[(U8)OP(text_node)] != EXACT) {
-                   c1 = c2 = -1000;
-               }
+               if (! HAS_TEXT(text_node)) c1 = c2 = -1000;
                else {
-                   s = (U8*)STRING(text_node);
+                   if (PL_regkind[(U8)OP(text_node)] == REF) {
+                       I32 n, ln;
+                       n = ARG(text_node);  /* which paren pair */
+                       ln = PL_regstartp[n];
+                       /* assume yes if we haven't seen CLOSEn */
+                       if (
+                           *PL_reglastparen < n ||
+                           ln == -1 ||
+                           ln == PL_regendp[n]
+                       ) {
+                           c1 = c2 = -1000;
+                           goto assume_ok_easy;
+                       }
+                       s = PL_bostr + ln;
+                   }
+                   else { s = (U8*)STRING(text_node); }
 
                    if (!UTF) {
                        c2 = c1 = *s;
@@ -3316,6 +3362,7 @@ S_regmatch(pTHX_ regnode *prog)
            }
            else
                c1 = c2 = -1000;
+       assume_ok_easy:
            PL_reginput = locinput;
            if (minmod) {
                CHECKPOINT lastcp;