JEP Draft: Deprecate memory-access methods in sun.misc.unsafe for removal

Re:JEP Draft: Deprecate memory-access methods in sun.misc.un... by kaba0 on Wednesday January 17, 2024 @03:56AM (#39025152)

> statically compiled languages

I don’t think it’s relevant here, the JIT compiler can do the same optimizations here.

If the branch predictor can basically 100% guess correctly (which will be the case in any correct program), it should not have any additional cost, besides taking up place in i$, so I would assume that that is responsible for the difference.

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Re:JEP Draft: Deprecate memory-access methods in sun.misc.un... by iscoelho on Wednesday January 17, 2024 @04:09AM (#39025263)

> I don’t think it’s relevant here, the JIT compiler can do the same optimizations here.

Correct. I was clarifying that the issue can be replicated in a "simpler" statically compiled benchmark.

> If the branch predictor can basically 100% guess correctly (which will be the case in any correct program), it should not have any additional cost

That isn't true. The CPU branch predictor has a cost no-matter what. Of course, it's a complicated story: https://blog.cloudflare.com/branch-predictor

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Re:JEP Draft: Deprecate memory-access methods in sun.misc.un... by kaba0 on Wednesday January 17, 2024 @04:48AM (#39025603)

Thanks! I definitely have to do some readup on that!

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