Handle J9+ using Objects.requireNonNull rather than .getClass for null checks #97
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Add more debug logging in prep for further work
kashike
approved these changes
May 27, 2021
LexManos
reviewed
May 28, 2021
| + } | ||
| + // Calling Objects.requireNonNull and discarding the result is a common pattern in normal code, so we have to be a bit more | ||
| + // cautious about stripping calls when a constructor takes parameters of the instance type | ||
| + // ex. given a class X, `Objects.requireNonNull(someInstanceOfX); new X(someInstanceOfX)` should not have the rNN stripped. |
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Tho this is an okay assumption, looking at where the JDK actually emits the null checks
We have the following cases:
Lambdas: Expr::method
Lambdas: LocalClass::new
Inners: new instance.Inner() 2?
Switch on string with zero cases.
The last one is referenced in a few places. It seems to be adding a null check when creating new instances of classes inside other anon classes?
Anyways, for now this would be an acceptable 'get it working' patch. However the filter system should be more robust and address the actual areas in which the compiler outputs null checks.
Note: The old .getClass() check wasn't as restrictive as i'm saying. But this is more for reference and 'doing it right'
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Broken out of #96
This is the simplest change -- javac generates nullness checks a bit differently starting with a Java 9 target. FF is patched to support both the old .getClass() and new Objects.requireNonNull() variants.
I tossed in some more debug logging since I was looking forward to some of the other decompile errors that were introduced at the same time.
Diffs (via VanillaGradle workspace)
1.16.5: no change
21w19a: https://paste.gg/p/zml/9e50e0aa7d7c4ab78790f7b5d4b575d1