Utils: add source locators

[mwachs5]

Contributor Checklist

• Did you add Scaladoc to every public function/method?
• Did you add at least one test demonstrating the PR?
• Did you delete any extraneous printlns/debugging code?
• Did you specify the type of improvement?
• [N/A] Did you add appropriate documentation in docs/src?
• Did you state the API impact?
• Did you specify the code generation impact?
• Did you request a desired merge strategy?
• Did you add text to be included in the Release Notes for this change?

Type of Improvement

• performance improvement

• backend code generation

API Impact

This adds implicits to Cat, Reg utils and Bitwise Utils. Which I think is a backwards-incompatible API change though no user code should actually have to change.

I renamed one of the SourceInfoTransform functions to match the pattern where we make it match the name of the arguments exactly, and had to update Mem.scala to match.

Backend Code Generation Impact

The resulting code will have more useful source locators for any utils.

Desired Merge Strategy

• Squash: The PR will be squashed and merged (choose this if you have no preference.

Release Notes

Add source locators for util functions Cat, those in Bitwise, and those in Reg

Reviewer Checklist (only modified by reviewer)

• Did you add the appropriate labels?
• Did you mark the proper milestone (Bug fix: 3.4.x, [small] API extension: 3.5.x, API modification or big change: 3.6.0)?
• Did you review?
• Did you check whether all relevant Contributor checkboxes have been checked?
• Did you mark as Please Merge?

[mwachs5]

For example this is now the output for the test added in CatSpec:

[info]   "circuit MyModule :
[info]     module MyModule :
[info]       input in : UInt<8>[2]
[info]       output out : UInt
[info]   
[info]       node _out_T = cat(in[0], in[1]) @[CatSpec.scala 69:17]
[info]       out <= _out_T @[CatSpec.scala 69:11]

before this change:

[info]   "circuit MyModule :
[info]     module MyModule :
[info]       input in : UInt<8>[2]
[info]       output out : UInt
[info]   
[info]       node _out_T = cat(in[0], in[1]) @[Cat.scala 32:95]
[info]       out <= _out_T @[CatSpec.scala 69:11]

[chick]

Looks good to me. I did not go deep in analysis
but code reads well and tests look good