Hi Claes,
Is the bootstrapping issue contributed by Class::getDeclaredConstructors
call in InnerClassLambdaMetafactory::buildCallSite?
I wonder how much performance gain compared to using
Lookup::findConstructor for non-capturing lambda case. If LMF uses
Lookup::findConstructor, it does not perform any security permission
check since it's a full privileged lookup and address JDK-8155659 lambda
bootstrapping issue with security manager. Is it easy to measure the
performance difference?
Mandy
On 5/14/20 7:39 AM, Claes Redestad wrote:
Hi,
JDK-8155090 added some measures to StringConcatFactory to prevent
certain bootstrapping issues. I think we should consider eagerly
initializing the StringConcatFactory base class during bootstrap
instead.
Doing so will add a tiny bit of class loading overhead to bootstrap
(which of course will be amortized on first use of SCF) but still this
would also be a good opportunity to clean up a little.
One straightforward means to do so is to move the CACHE, DUMPER and
CACHE_ENABLE fields to BytecodeStringBuilderStrategy, since it's the
only place where they are used (the MethodHandle based strategies don't
manually spin classes and rely on LF sharing to de-duplicate shared
components).
Webrev: http://cr.openjdk.java.net/~redestad/8245024/open.00/
Bug: https://bugs.openjdk.java.net/browse/JDK-8245024
This reduces initialization overhead and simplifices bootstraps for the
default case, while still passing relevant test cases such as test/jdk
/java/lang/String/concat/WithSecurityManager.java for all strategies.
Testing: tier1-2
Thanks!
/Claes
