RFR (XS) 8156803: Turn StressLCM/StressGCM flags to diagnostic

[Christian Tornqvist]

Hi Aleksey,

FC for HS is in 4h, after that you can't check RFE's in. I suggest you postpone this change to the next minor release.

Thanks,
Christian

-----Original Message-----
From: hotspot-compiler-dev [mailto:hotspot-compiler-dev-bounces at openjdk.java.net] On Behalf Of Aleksey Shipilev
Sent: Wednesday, May 11, 2016 5:33 PM
To: hotspot compiler <hotspot-compiler-dev at openjdk.java.net>
Subject: RFR (XS) 8156803: Turn StressLCM/StressGCM flags to diagnostic

Hi,

In order to better test the concurrency support in JVM, we introduced StressLCM/StressGCM flags that randomize C2's instruction scheduling:

  develop(bool, StressLCM, false, \
          "Randomize instruction scheduling in LCM") \

  develop(bool, StressGCM, false, \
          "Randomize instruction scheduling in GCM") \

These, however, require fastdebug build, which is not really fast for concurrency testing, as it does lots of asserts in VM codepaths (notably, GC). We would be better off turning these flags to diagnostic, to pop out in product builds.

Bug:
  https://bugs.openjdk.java.net/browse/JDK-8156803

Webrev:
  http://cr.openjdk.java.net/~shade/8156803/webrev.01/

Testing: manual testing with local x86_64/release build. I don't think we need to waste machine time on deeply testing this trivial change?

Thanks,
-Aleksey