(search_buffer): Don't use Boyer-Moore

to search for an invalid multibyte code.
In unibyte case, no need to check whether there are translations
in more than one charset; just set charset_base to 0.

1 files changed, 13 insertions, 21 deletions

diff --git a/src/search.c b/src/search.c
index e4877b5f498..fee6b835bd3 100644
--- a/src/search.c
+++ b/src/search.c
@@ -1142,7 +1142,7 @@ search_buffer (string, pos, pos_byte, lim, lim_byte, n,
       int multibyte = !NILP (current_buffer->enable_multibyte_characters);
       unsigned char *base_pat = XSTRING (string)->data;
       int charset_base = -1;
-      int simple = 1;
+      int boyer_moore_ok = 1;
 
       /* MULTIBYTE says whether the text to be searched is multibyte.
          We must convert PATTERN to match that, or we will not really
@@ -1204,6 +1204,12 @@ search_buffer (string, pos, pos_byte, lim, lim_byte, n,
                 }
 
               c = STRING_CHAR_AND_LENGTH (base_pat, len_byte, in_charlen);
+
+              /* If we are searching for something strange,
+                 an invalid multibyte code, don't use boyer-moore.  */
+              if (! ASCII_BYTE_P (c))
+                boyer_moore_ok = 0;
+
               /* Translate the character, if requested.  */
               TRANSLATE (translated, trt, c);
               /* If translation changed the byte-length, go back
@@ -1229,8 +1235,8 @@ search_buffer (string, pos, pos_byte, lim, lim_byte, n,
                   else if (charset_base != charset_base_code)
                     /* If two different rows appear, needing translation,
                        then we cannot use boyer_moore search.  */
-                    simple = 0;
-                    /* ??? Handa: this must do simple = 0
+                    boyer_moore_ok = 0;
+                    /* ??? Handa: this must do boyer_moore_ok = 0
                        if c is a composite character.  */
                 }
 
@@ -1243,9 +1249,11 @@ search_buffer (string, pos, pos_byte, lim, lim_byte, n,
         }
       else
         {
+          /* Unibyte buffer.  */
+          charset_base = 0;
           while (--len >= 0)
             {
-              int c, translated, inverse;
+              int c, translated;
 
               /* If we got here and the RE flag is set, it's because we're
                  dealing with a regexp known to be trivial, so the backslash
@@ -1257,22 +1265,6 @@ search_buffer (string, pos, pos_byte, lim, lim_byte, n,
                 }
               c = *base_pat++;
               TRANSLATE (translated, trt, c);
-              TRANSLATE (inverse, inverse_trt, c);
-
-              /* Did this char actually get translated?
-                 Would any other char get translated into it?  */
-              if (translated != c || inverse != c)
-                {
-                  /* Keep track of which character set row
-                     contains the characters that need translation.  */
-                  int charset_base_code = c & ~0xff;
-                  if (charset_base == -1)
-                    charset_base = charset_base_code;
-                  else if (charset_base != charset_base_code)
-                    /* If two different rows appear, needing translation,
-                       then we cannot use boyer_moore search.  */
-                    simple = 0;
-                }
               *pat++ = translated;
             }
         }
@@ -1281,7 +1273,7 @@ search_buffer (string, pos, pos_byte, lim, lim_byte, n,
       len = raw_pattern_size;
       pat = base_pat = patbuf;
 
-      if (simple)
+      if (boyer_moore_ok)
         return boyer_moore (n, pat, len, len_byte, trt, inverse_trt,
                             pos, pos_byte, lim, lim_byte,
                             charset_base);