FW: JDK 10 RFR JDK-8167425: Redundant code in method PerfLongVariant::sample

[Shafi Ahmad]

Hi,

Summary:
It's a very small change to a single file. 

void PerfLongVariant::sample() {
 
-  assert(_sample_helper != NULL || _sampled != NULL, "unexpected state");
+  // JJJ - This should not happen.  Maybe the first sample is taken  //  
+ while the _sample_helper is being null'ed out.
+  // assert(_sample_helper != NULL || _sampled != NULL, "unexpected  state");
+ if (_sample_helper == NULL) return;
 
  if (_sample_helper != NULL) {
    *(jlong*)_valuep = _sample_helper->take_sample();
  }
  else if (_sampled != NULL) {
    *(jlong*)_valuep = *_sampled;
  }
}
Above five lines are modified in changeset http://hg.openjdk.java.net/jdk8/jdk8/hotspot/rev/da91efe96a93#l802.12
Due to the addition of NULL check and return
  if (_sample_helper == NULL) return;
the else-if block becomes redundant and statement 'if (_sample_helper != NULL)' is not needed.

Webrev link: http://cr.openjdk.java.net/~shshahma/8167425/webrev.00/
Jdk10 bug link: https://bugs.openjdk.java.net/browse/JDK-8167425

Testing: jprt.

Thanks,
Shafi