performance surprise with Object.hashCode()

Vitaly Davidovich vitalyd at gmail.com
Mon May 13 12:28:38 PDT 2013


Interesting, I didn't know about the DisableIntrinsic flag.  I think the
o_i takes a hit because the hashCode there is so trivial that the guards
themselves cost more in pure overhead.

What I'm curious about is why there's no polymorphic inline cache? Is it
that intrinsics don't receive profile information and don't have deopt
support? It's probably the case that most classes don't override hashCode
but this does penalize classes with trivial ones.

Sent from my phone
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/attachments/20130513/a59a0e17/attachment.html 


More information about the hotspot-compiler-dev mailing list