Make dumpcolors() have tolerable performance when using 32-bit chr,

as we do (and upstream Tcl doesn't).  The loop limit might be subject
to negotiation if anyone ever tries to do regex debugging in Far
Eastern languages, but for now 1000 seems plenty.  CHR_MAX was right out :-(

src/backend/regex/regc_color.c

@@ -28,7 +28,7 @@
  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- * $PostgreSQL: pgsql/src/backend/regex/regc_color.c,v 1.5 2005/10/15 02:49:24 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/regex/regc_color.c,v 1.6 2007/10/06 16:18:09 tgl Exp $
  *
  *
  * Note that there are some incestuous relationships between this code and
@@ -722,11 +722,15 @@ dumpcolors(struct colormap * cm,
 			else
 				fprintf(f, "#%2ld%s(%2d): ", (long) co,
 						has, cd->nchrs);
-			/* it's hard to do this more efficiently */
-			for (c = CHR_MIN; c < CHR_MAX; c++)
-				if (GETCOLOR(cm, c) == co)
-					dumpchr(c, f);
-			assert(c == CHR_MAX);
+			/*
+			 * Unfortunately, it's hard to do this next bit more efficiently.
+			 *
+			 * Spencer's original coding has the loop iterating from CHR_MIN
+			 * to CHR_MAX, but that's utterly unusable for 32-bit chr.
+			 * For debugging purposes it seems fine to print only chr
+			 * codes up to 1000 or so.
+			 */
+			for (c = CHR_MIN; c < 1000; c++)
 				if (GETCOLOR(cm, c) == co)
 					dumpchr(c, f);
 			fprintf(f, "\n");