Lock coarsening LogCompilation output?
cnewland at chrisnewland.com
Wed Jul 22 14:04:03 UTC 2015
I'm building support into JITWatch for highlighting eliminated heap
allocations and locks (either via elision or coarsening) and I'm confused
by the LogCompilation output in this case:
Given the source code here:
Which consists of two synchronized(this) regions separated by a single
statement modifying a local primitive.
I get the following LogCompilation output:
Which has the following elimination info in the optimizer phase:
<jvms bci='61' method='818'/>
BCI 61 refers to the 2nd synchronized block's monitor enter which I
believe will be eliminated due to coarsening but I don't understand what
tag means, and why it doesn't contain a jvms tag?
Does it mean the first synchronized block has also been eliminated (via
elision) ? I don't see any "lock cmpxchg" related to the first
synchronized block in the PrintAssembly?
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