From 48045f99e574d1d8e049a413f5b3f40d33898dc2 Mon Sep 17 00:00:00 2001
From: Boris Kolpackov <boris@kolpackov.net>
Date: Fri, 25 Sep 2009 15:51:11 +0000
Subject: [PATCH] Performance improvement.

---
 ChangeLog  | 5 +++++
 implicit.c | 4 ++++
 2 files changed, 9 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 9caef15a..545ea53c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2009-09-25 Boris Kolpackov  <boris@codesynthesis.com>
+
+	* implicit.c (pattern_search): Terminate early if we haven't
+	found any rules to try (performance improvement).
+
 2009-09-25 Boris Kolpackov  <boris@codesynthesis.com>
 
 	* implicit.c (pattern_search): Merge three parallel arrays,
diff --git a/implicit.c b/implicit.c
index 6db4d0ed..c3e35f7e 100644
--- a/implicit.c
+++ b/implicit.c
@@ -390,6 +390,10 @@ pattern_search (struct file *file, int archive,
         }
     }
 
+  /* Bail out early if we haven't found any rules. */
+  if (nrules == 0)
+    goto done;
+
   /* If we have found a matching rule that won't match all filenames,
      retroactively reject any non-"terminal" rules that do always match.  */
   if (specific_rule_matched)