Change the Builder to record the Root Optional Group in its Group Stack.
This is done to later enable error checking that group definitions are
nested correctly.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add support for optional groups.  These are groups of statements with
optional functionality.  The primary use case is intended for verification
code to "extract" such code into bound modules.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

- Provide a public simpleClassName utility to generate simple class names in a non-error prone way, particularly when generating inner class names. All typeNames are modified to now use this utility.
- Mixing HasAutoTypename into anonymous bundles is now prohibited by the compiler, as this inevitably leads to name conflicts.

Change the reported version of Chisel-emitted FIRRTL to 3.3.0.  Version
3.2.0 includes groups and Chisel is currently emitting things that are not
in a spec version yet, e.g., property lists.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add tests of FixedIORawModule and friends.  Rename the file containing
FixedIORawModule to "FixedIOModule".  This previously used the old
"Polymorphic" name.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add a new module hierarchy that promotes the type of the IO of that module
to a type parameter.  This module hierarchy includes:

  1. FixedIOBaseModule
  2. FixedIORawModule
  3. FixedIOBlackBox

Both (2) and (3) inherit from (1).  These modules are all "fixed" in the
type of their IO.  It follows that no more IO are allowed to be created
other than what is in the type.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

Add a `private[chisel3]` ability to block further IO creation in a
`BaseModule`.  This is intended for advanced, in-tree APIs that need to
disallow the creation of further IO by a user.  This API has mutable state
to track if more IO is allowed to be created, a method to get the
value, and a method to set the module to disallow further IO creation.
This one-way setting (h/t @jackkoenig) tries to keep this as locked down
as possible.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

* MixedVec is a Seq
* Add a test for MixedVec being a Seq
* fix integration test -- note that this same change would have been needed for VecInit(Vec(...))

Change `FlatIO` to work for any `Data` as opposed to just for `Record`.
For non-`Record`, have this behave the same as `IO`.  I.e., there is no
prefix stripping.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@sifive.com>

This improves error messages involving views where the view maps to a
single Data. The error messages on legacy connections (:= and <>)
involving views that do not correspond 1-1 with a single target Data are
still bad, but connectables (eg. :#=) do benefit even in that case.

- Add a `HasAutoTypename` experimental trait, which can be mixed into `Record` classes to generate a statement of the form `override def typeName = '...'` using the compiler plugin. Allows users to automatically generate stable, standardized type names without unnecessary boilerplate code

This is an automated commit generated by Chisel's CD flow.

Co-authored-by: chiselbot <chiselbot@users.noreply.github.com>

The new `HasTypeAlias` trait enables the emission of FIRRTL type alias statements representing the structural type of a `Bundle`. This is done by mixing `HasTypeAlias` into a `Bundle`, then overriding `def aliasName` with an invocation of a `BundleAlias(...)` object.

Done by adding a named anchor to the Cookbook to make linking easier.
Also fix a minor issue with the website Makefile where stale markdown
files could be left around and would not be overwritten when using the
common alias cp alias `cp -i`.

Add `AnyRef` type and rework `PropertyType.getPropertyType`

firrtl: Emit under 3.2.0 (not released) to cover property features.

While this doesn't exist, some of the property-related features
don't exist in the claimed 3.1.0.

This is an automated commit generated by Chisel's CD flow.

Co-authored-by: chiselbot <chiselbot@users.noreply.github.com>

Previously they only used Strings as keys.

Properties can be fields of Bundles and used in wires.

add Path property type