util: Add a README file for the m5 utility.

[gem5.git] / util / rundiff

diff --git a/util/rundiff b/util/rundiff
index 9376e4b9ede9b6da121f9138d0ae207ea25879b6..b988d5db2b95fdac494634ef432e5b3464877f10 100755 (executable)
--- a/util/rundiff
+++ b/util/rundiff
@@ -36,11 +36,11 @@
 # "filename" is a pipe (|).  Thus to compare the instruction traces
 # from two versions of m5 (m5a and m5b), you can do this:
 #
-# rundiff 'm5a --trace:flags=InstExec |' 'm5b --trace:flags=InstExec |'
+# rundiff 'm5a --traceflags=InstExec |' 'm5b --traceflags=InstExec |'
 #
 
 use strict;
-
+use FileHandle;
 use Getopt::Std;
 
 #
@@ -162,6 +162,12 @@ sub printdiff
 
     # Set $postcontext to print the next $postcontext_lines matching lines.
     $postcontext = $postcontext_lines;
+
+    # Normally we flush after the postcontext lines are printed, but if
+    # the user has decreed that there aren't any we need to flush now
+    if ($postcontext == 0) {
+        STDOUT->flush();
+    }
 }
 
 
@@ -286,10 +292,12 @@ while (1) {
        # figure out what to do with this line
        if ($postcontext > 0) {
            # we're in the post-context of a diff: print it
-           $postcontext--;
            print ' ', $l1;
            $lineno1++;
            $lineno2++;
+            if (--$postcontext == 0) {
+                STDOUT->flush();
+            }
        }
        else {
            # we're in the middle of a matching region... save this