Withdrawn: 8315066: Add unsigned bounds and known bits to TypeInt/Long

[duke]

On Sun, 27 Aug 2023 12:26:22 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. The new constraints are applied to identity and value calls of the common nodes (Add, Sub, L/R/URShift, And, Or, Xor, bit counting, Cmp, Bool, ConvI2L/L2I), the detailed ideas for each node will be presented below.
> 
> 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.
> 
> Please kindly review, thanks very much.
> 
> Testing
> 
> - [x] GHA
> - [x] Linux x64, tier 1-4

This pull request has been closed without being integrated.

-------------

PR: https://git.openjdk.org/jdk/pull/15440