[12] RFR(S) 8206963: [AOT] bug with multiple class loaders

Andrew Haley aph at redhat.com
Sat Oct 6 09:24:17 UTC 2018


On 10/05/2018 03:36 PM, Vladimir Kozlov wrote:
> After investigations and discussions I suggest that AOT should not support custom class loaders. The main issue is 
> during AOT compilation we don't know anything about them and their constrains. JAOTC uses only standard builtin loaders.
> Otherwise we would have to add class runtime checks to all field accesses and inlined code and create separate memory 
> for class pointers (AOT 'got' cells) per method which may cause significant performance regression.

For interest, we did get this working correctly in GCJ, regardless of
class loader.  We used a cryptographic hash of the entire class file
to look up the correct compiled code and then resolved the references
from the code using the usual JVM rules. This is always correct, I
think.

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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