RFR: 8315066: Add unsigned bounds and known bits to TypeInt/Long [v9]

[Vladimir Kozlov]

On Tue, 3 Sep 2024 20:39:41 GMT, Quan Anh Mai <qamai at openjdk.org> wrote:

>> Hi,
>> 
>> This patch adds unsigned bounds and known bits constraints to TypeInt and TypeLong. This opens more transformation opportunities in an elegant manner as well as helps avoid some ad-hoc rules in Hotspot.
>> 
>> In general, a TypeInt/Long represents a set of values x that satisfies: x s>= lo && x s<= hi && x u>= ulo && x u<= uhi && (x & zeros) == 0 && (~x & ones) == 0. These constraints are not independent, e.g. an int that lies in [0, 3] in signed domain must also lie in [0, 3] in unsigned domain and have all bits but the last 2 being unset. As a result, we must normalize the constraints (tighten the constraints so that they are optimal) before constructing a TypeInt/Long instance.
>> 
>> This is extracted from #15440 , node value transformations are left for later PRs. I have also added unit tests to verify the soundness of constraint normalization.
>> 
>> Please kindly review, thanks a lot.
>> 
>> Testing
>> 
>> - [x] GHA
>> - [x] Linux x64, tier 1-4
>
> Quan Anh Mai has updated the pull request incrementally with one additional commit since the last revision:
> 
>   move static_asserts

Passing by comment.

> Do you think it would be more suitable to make the type dumping more clever or to modify existing tests?

I am fine with modifying tests when we agree on output format.

Can you use `int:[0..max_int, 0..max_int]` instead of `^` which associates with an operator for me.
For me it will be easy to interpret it as `[_lo, _hi] range of values.

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PR Comment: https://git.openjdk.org/jdk/pull/17508#issuecomment-2327570677