Unrevert most of regexp reentrancy abort patch

The problem was in:
  * src/syntax.c (update_syntax_table_forward): Propertize even when truncated
which is hence not unreverted.
The rest is:
* src/syntax.h (UPDATE_SYNTAX_TABLE_FORWARD_FAST):
(UPDATE_SYNTAX_TABLE_FAST): Re-introduce.
All callers in regex.c changed back to the _FAST versions.

* test/automated/message-mode-tests.el: Tweak the test to rely on auto
propertization in backward-sexp.

2 files changed, 23 insertions, 9 deletions

diff --git a/src/regex.c b/src/regex.c
index dcf286454b3..4e00fd15dc9 100644
--- a/src/regex.c
+++ b/src/regex.c
@@ -5945,12 +5945,12 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
 #ifdef emacs
                 ssize_t offset = PTR_TO_OFFSET (d - 1);
                 ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
-                UPDATE_SYNTAX_TABLE (charpos);
+                UPDATE_SYNTAX_TABLE_FAST (charpos);
 #endif
                 GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
                 s1 = SYNTAX (c1);
 #ifdef emacs
-                UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
+                UPDATE_SYNTAX_TABLE_FORWARD_FAST (charpos + 1);
 #endif
                 PREFETCH_NOLIMIT ();
                 GET_CHAR_AFTER (c2, d, dummy);
@@ -5987,7 +5987,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
 #ifdef emacs
               ssize_t offset = PTR_TO_OFFSET (d);
               ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
-              UPDATE_SYNTAX_TABLE (charpos);
+              UPDATE_SYNTAX_TABLE_FAST (charpos);
 #endif
               PREFETCH ();
               GET_CHAR_AFTER (c2, d, dummy);
@@ -6032,7 +6032,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
 #ifdef emacs
               ssize_t offset = PTR_TO_OFFSET (d) - 1;
               ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
-              UPDATE_SYNTAX_TABLE (charpos);
+              UPDATE_SYNTAX_TABLE_FAST (charpos);
 #endif
               GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
               s1 = SYNTAX (c1);
@@ -6047,7 +6047,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
                   PREFETCH_NOLIMIT ();
                   GET_CHAR_AFTER (c2, d, dummy);
 #ifdef emacs
-                  UPDATE_SYNTAX_TABLE_FORWARD (charpos);
+                  UPDATE_SYNTAX_TABLE_FORWARD_FAST (charpos);
 #endif
                   s2 = SYNTAX (c2);
 
@@ -6076,7 +6076,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
 #ifdef emacs
               ssize_t offset = PTR_TO_OFFSET (d);
               ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
-              UPDATE_SYNTAX_TABLE (charpos);
+              UPDATE_SYNTAX_TABLE_FAST (charpos);
 #endif
               PREFETCH ();
               c2 = RE_STRING_CHAR (d, target_multibyte);
@@ -6119,7 +6119,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
 #ifdef emacs
               ssize_t offset = PTR_TO_OFFSET (d) - 1;
               ssize_t charpos = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
-              UPDATE_SYNTAX_TABLE (charpos);
+              UPDATE_SYNTAX_TABLE_FAST (charpos);
 #endif
               GET_CHAR_BEFORE_2 (c1, d, string1, end1, string2, end2);
               s1 = SYNTAX (c1);
@@ -6134,7 +6134,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
                   PREFETCH_NOLIMIT ();
                   c2 = RE_STRING_CHAR (d, target_multibyte);
 #ifdef emacs
-                  UPDATE_SYNTAX_TABLE_FORWARD (charpos + 1);
+                  UPDATE_SYNTAX_TABLE_FORWARD_FAST (charpos + 1);
 #endif
                   s2 = SYNTAX (c2);
 
@@ -6157,7 +6157,7 @@ re_match_2_internal (struct re_pattern_buffer *bufp, const_re_char *string1,
             {
               ssize_t offset = PTR_TO_OFFSET (d);
               ssize_t pos1 = SYNTAX_TABLE_BYTE_TO_CHAR (offset);
-              UPDATE_SYNTAX_TABLE (pos1);
+              UPDATE_SYNTAX_TABLE_FAST (pos1);
             }
 #endif
             {
diff --git a/src/syntax.h b/src/syntax.h
index 06ce0ec55df..eb154e088c9 100644
--- a/src/syntax.h
+++ b/src/syntax.h
@@ -186,6 +186,13 @@ UPDATE_SYNTAX_TABLE_FORWARD (ptrdiff_t charpos)
                                  false, gl_state.object);
 }
 
+INLINE void
+UPDATE_SYNTAX_TABLE_FORWARD_FAST (ptrdiff_t charpos)
+{
+  if (parse_sexp_lookup_properties && charpos >= gl_state.e_property)
+    update_syntax_table (charpos + gl_state.offset, 1, false, gl_state.object);
+}
+
 /* Make syntax table state (gl_state) good for CHARPOS, assuming it is
    currently good for a position after CHARPOS.  */
 
@@ -205,6 +212,13 @@ UPDATE_SYNTAX_TABLE (ptrdiff_t charpos)
   UPDATE_SYNTAX_TABLE_FORWARD (charpos);
 }
 
+INLINE void
+UPDATE_SYNTAX_TABLE_FAST (ptrdiff_t charpos)
+{
+  UPDATE_SYNTAX_TABLE_BACKWARD (charpos);
+  UPDATE_SYNTAX_TABLE_FORWARD_FAST (charpos);
+}
+
 /* Set up the buffer-global syntax table.  */
 
 INLINE void