Create a character map to use for locating stop-points in strings.

In various places we were passing flags and characters to compare, then
using complex conditionals to see where to stop in string searches.
Performance numbers reveal that we were spending as much as 23% of our
processing time in these functions, most of it in the comparison lines.
Instead create a character map and use a single bitwise comparison to
determine if this is any one of the stop characters.

1 files changed, 5 insertions, 4 deletions

diff --git a/dir.c b/dir.c
index 87b8eb3..5681275 100644
--- a/dir.c
+++ b/dir.c
@@ -16,6 +16,7 @@ this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "makeint.h"
 #include "hash.h"
+#include "dep.h"
 
 #ifdef  HAVE_DIRENT_H
 # include <dirent.h>
@@ -84,21 +85,21 @@ dosify (const char *filename)
   df = dos_filename;
 
   /* First, transform the name part.  */
-  for (i = 0; *filename != '\0' && i < 8 && *filename != '.'; ++i)
+  for (i = 0; i < 8 && ! STOP_SET (*filename, MAP_DOT|MAP_NUL); ++i)
     *df++ = tolower ((unsigned char)*filename++);
 
   /* Now skip to the next dot.  */
-  while (*filename != '\0' && *filename != '.')
+  while (! STOP_SET (*filename, MAP_DOT|MAP_NUL))
     ++filename;
   if (*filename != '\0')
     {
       *df++ = *filename++;
-      for (i = 0; *filename != '\0' && i < 3 && *filename != '.'; ++i)
+      for (i = 0; i < 3 && ! STOP_SET (*filename, MAP_DOT|MAP_NUL); ++i)
         *df++ = tolower ((unsigned char)*filename++);
     }
 
   /* Look for more dots.  */
-  while (*filename != '\0' && *filename != '.')
+  while (! STOP_SET (*filename, MAP_DOT|MAP_NUL))
     ++filename;
   if (*filename == '.')
     return filename;