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8329750: Change Universe functions to return more specific Klass* types #18652

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8329750: Change Universe functions to return more specific Klass* types #18652

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8329750: Change Universe functions to return more specific Klass* types
stefank Apr 5, 2024
d36f650
Update src/hotspot/share/classfile/systemDictionary.cpp
stefank Apr 8, 2024
36bef54
Revert "Update src/hotspot/share/classfile/systemDictionary.cpp "
stefank Apr 8, 2024
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3 changes: 2 additions & 1 deletion src/hotspot/share/classfile/systemDictionary.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -367,7 +367,8 @@ Klass* SystemDictionary::resolve_array_class_or_null(Symbol* class_name,
k = k->array_klass(ndims, CHECK_NULL);
}
} else {
k = Universe::typeArrayKlass(t);
TypeArrayKlass* tak = Universe::typeArrayKlass(t);
k = tak->array_klass(ndims, CHECK_NULL);
k = k->array_klass(ndims, CHECK_NULL);
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this looks puzzling. Why are there two array_klass calls now? Add short comments to explain.

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I sort of see now but am getting squint lines. It's not important for performance to eliminate a virtual call here.

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Hmm. Having two array_klass calls were not intentional. I accepted Dean's suggestion in the GitHub UI, but that didn't remove the old array_klass. I think I'll revert that change given that it is not important to devirtualize this.

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Oh good because I was going to need a lot more coffee to understand why there was a second call. Thanks.

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Why devirtualize elsehwere but not here? Maybe it's not a big deal.

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Or to put it another way, what's the advantage of using TypeArrayKlass* tak in similar situations below?

}
return k;
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