Withdrawn: 8315066: Add unsigned bounds and known bits to TypeInt/Long

[duke]

On Sat, 20 Jan 2024 19:23:23 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

This pull request has been closed without being integrated.

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PR: https://git.openjdk.org/jdk/pull/17508