RFR(S): jdk11u-dev backport 8216556: Unnecessary liveness computation with JVMTI

[Lindenmaier, Goetz]

Hi Martin, 

you well intergrated this change to 11. 
Thanks for downporting it, it will help the debugging
performance slightly.

Best regards,
  Goetz.



> -----Original Message-----
> From: Doerr, Martin
> Sent: Montag, 6. Mai 2019 14:54
> To: 'hotspot-compiler-dev at openjdk.java.net' <hotspot-compiler-
> dev at openjdk.java.net>; Lindenmaier, Goetz <goetz.lindenmaier at sap.com>
> Subject: RFR(S): jdk11u-dev backport 8216556: Unnecessary liveness
> computation with JVMTI
> 
> Hi,
> 
> 
> 
> I'd like to backport this change to jdk11u because it's very simply and avoids
> some unnecessary overhead.
> 
> Applies almost cleanly (only needs manual resolution because neighboring
> hunk has changed: CompileTheWorld removal).
> 
> 
> 
> bug:
> 
> https://bugs.openjdk.java.net/browse/JDK-8216556
> 
> 
> 
> original change:
> 
> http://hg.openjdk.java.net/jdk/jdk/rev/91ab128a65a3
> 
> 
> 
> jdk11u webrev:
> 
> http://cr.openjdk.java.net/~mdoerr/8216556_JVMTI_liveness/jdk11u/webrev.
> 00/
> 
> 
> 
> I only had to reapply the change around
> 
> "if (CURRENT_ENV->should_retain_local_variables() || DeoptimizeALot ||
> CompileTheWorld) {"
> 
> (ciMethod.cpp) because CompileTheWorld was removed.
> 
> 
> 
> Please review.
> 
> 
> 
> Best regards,
> 
> Martin
> 
>