[Bug]: Boxing of structs to compute hashcode is causing excessive allocations

[wrall]

NuGet Product Used

Other/NA

Product Version

All

Worked before?

No response

Impact

Other

Repro Steps & Context

The HashCodeCombiner takes an object parameter in its AddObject method and when passed a value type such as a struct or enum value, it boxes it to do a null check and then compute the hashcode. This allocates boxed objects that are short-lived and not necessary.

After the fix for #11669, this becomes one of the top sources of allocation for NuGet restore for some scenarios.

Verbose Logs

No response

[wrall]

Note that a similar issue was handled in the past in #10917.