... needed some bad hax to get IOs of UserModules

option method.
Remove commented out Firrterpreter
Since TreadleBackend is new code (based on FirrterpreterBackend) I
have made it scalastyle clean

Add chisel options to select backend
Made treadle the default
Added necessary glue to hook in Treadle
Changed build.sbt to add Treadle dependency

If autoclonetype is unable to determine an outer class, this attempts to insert a null (and give a deprecation warning), preserving old behavior (in some cases) where the new behavior doesn't work.

This doesn't provide full compatibility with old autoclonetype: this does not attempt null insertion in the general first argument (if it's not an outer class reference). Reasoning is that inserting a null for an explicit argument is probably not the right thing to do, and will likely cause a difficult-to-debug NullPointerException (whereas that would be unlikely for an outer class, which is not always referenced in Bundle subclass code).

PiperOrigin-RevId: 187258707

SyncReadMem.read with an enable signal currently only works in
compatibility mode, where Wires are implicitly initialized to
DontCare.  Fix by explicitly assigning DontCare to the Wire.

This might fix #775.

Makes Builder.updateBundleStack a bit stricter in deciding how many stack frames to discard by additionally matching against method names and deleting stack frames at or above the frame currently being inserted.

* Generalize ChiselAnnotation

This allows us to delay creation of Annotations till elaboration is
complete. Also update all annotation-related code.

* Add RunFirrtlTransform

Use a Chisel-specific RunFirrtlTransform API to preserve behavior of old
ChiselAnnotation (now called ChiselLegacyAnnotation)

* Use unique test directories in ChiselRunners.compile

Add companion objects to macro classes

Workaround for unconditional invalidation of macro classes in
incremental recompilation

* Remove checkboxes from issue/pr templates.

* Compact template text and try to make meta information comments.

* Respond to comments - remove bullet point usage.