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A comment on JEP Draft: Deprecate memory-access methods in sun.misc.unsafe for removal. Parent comment

Re:JEP Draft: Deprecate memory-access methods in sun.misc.un... by xxs on Wednesday January 17, 2024 @02:14AM (#39024322)
Bounds checks are not 'free' but predicted ones are cheap. There are way to convince the JIT to remove them - in cases it can prove the index doesn't exceed the byte array, so explicit checks with the length of the array may improve the performance.

The stuff gets worse with DirectByteBuffers as the JIT has to work harder. Unsafe allows to 'remove' all bound checks, but it may prevent some other optimizations.

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Re:JEP Draft: Deprecate memory-access methods in sun.misc.un... by iscoelho on Wednesday January 17, 2024 @03:34AM (#39024953)
> but it may prevent some other optimizations.

I see this mentioned a few times in this thread, but I haven't experienced this in practice (and I've written a lot of unsafe in Java). Are there any examples of this?

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