[13] RFR(S): 8218201: Failures when vmIntrinsics::_getClass is not inlined

Tobias Hartmann tobias.hartmann at oracle.com
Thu Mar 7 12:54:50 UTC 2019


please review the following patch:

When intrinsification is disabled, the BCEscapeAnalyzer marks the return value of the (native)
method Object::getClass as "return allocated value" which means that "only newly allocated unescaped
objects are returned". The OptimizePtrCompare optimization then uses this information to incorrectly
fold 'obj.getClass() == Object.class' (see TestGetClass.java:39) to always false.

This is a very old issue and I can't trace back why a special case for the _getClass intrinsic has
been added to the BCEscapeAnalyzer. Since I don't think we should make any assumptions about the
returned Object, I've removed the special case.


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