[llvm] Adding Matching and Inference Functionality to Propeller-PR2 (PR #162963)

[via llvm-commits]

wdx727 wrote:

> Could you please split this into at least 3 PRs. I feel a bit overwhelmed by the number of files touched in this PR.
> 
> The first PR should add the MachineBlockHashInfo pass. The second PR would implement reading the BB hash from the basic block section profile. The third PR will then introduce matching and inference (for this one please add a reviewer more familiar with profile inference like @spupyrev and @htyu).

No problem. Currently, this PR only adds the MachineBlockHashInfo pass.

https://github.com/llvm/llvm-project/pull/162963