dfa: separate dfaexec function to help optimization by compiler

* src/dfa.c (dfaexec_main): Rename from dfaexec, add inline attribute.
(dfaexec_mb): New function.  Run it when d->multibyte is true.   For this
function inlination must be avoided.
(dfaexec_sb): New function.  Run it when d->multibyte is false.  For this
function inlination must be avoided.
(dfaexec): Call dfaexec_mb or dfaexec_sb accoding to d->multibyte.

1 files changed, 29 insertions, 6 deletions

diff --git a/src/dfa.c b/src/dfa.c
index 5930e542..ff23c07c 100644
--- a/src/dfa.c
+++ b/src/dfa.c
@@ -3267,9 +3267,9 @@ skip_remains_mb (struct dfa *d, unsigned char const *p,
    Finally, if BACKREF is non-NULL set *BACKREF to indicate whether we
    encountered a back-reference (1) or not (0).  The caller may use this
    to decide whether to fall back on a backtracking matcher.  */
-char *
-dfaexec (struct dfa *d, char const *begin, char *end,
-         int allow_nl, size_t *count, int *backref)
+static inline char *
+dfaexec_main (struct dfa *d, char const *begin, char *end,
+             int allow_nl, size_t *count, int *backref, bool const multibyte)
 {
   state_num s, s1;              /* Current state.  */
   unsigned char const *p, *mbp; /* Current input character.  */
@@ -3291,7 +3291,7 @@ dfaexec (struct dfa *d, char const *begin, char *end,
   saved_end = *(unsigned char *) end;
   *end = eol;
 
-  if (d->multibyte)
+  if (multibyte)
     {
       memset (&d->mbs, 0, sizeof d->mbs);
       if (! d->mb_match_lens)
@@ -3303,7 +3303,7 @@ dfaexec (struct dfa *d, char const *begin, char *end,
 
   for (;;)
     {
-      if (d->multibyte)
+      if (multibyte)
         {
           while ((t = trans[s]) != NULL)
             {
@@ -3387,7 +3387,7 @@ dfaexec (struct dfa *d, char const *begin, char *end,
             }
 
           s1 = s;
-          if (d->multibyte)
+          if (multibyte)
             {
               /* Can match with a multibyte character (and multicharacter
                  collating element).  Transition table might be updated.  */
@@ -3432,6 +3432,29 @@ dfaexec (struct dfa *d, char const *begin, char *end,
   return (char *) p;
 }
 
+static char *__attribute__((noinline))
+dfaexec_mb (struct dfa *d, char const *begin, char *end,
+           int allow_nl, size_t *count, int *backref)
+{
+  return dfaexec_main (d, begin, end, allow_nl, count, backref, true);
+}
+
+static char *__attribute__((noinline))
+dfaexec_sb (struct dfa *d, char const *begin, char *end,
+           int allow_nl, size_t *count, int *backref)
+{
+  return dfaexec_main (d, begin, end, allow_nl, count, backref, false);
+}
+
+char *
+dfaexec (struct dfa *d, char const *begin, char *end,
+         int allow_nl, size_t *count, int *backref)
+{
+  return (d->multibyte
+    ? dfaexec_mb (d, begin, end, allow_nl, count, backref)
+    : dfaexec_sb (d, begin, end, allow_nl, count, backref));
+}
+
 struct dfa *
 dfasuperset (struct dfa const *d)
 {