Std Library Discussion

FIRRTL Feedback:
   Can we write an asynchronous FIFO using our implicit clock port semantics? (Patrick)
      Unclear.

   Can't mux between Bundle Types. (Stephen)
      We think that is ok.

   Bit-wise operation on SInts. Knocking down low bits. (Stephen)
      Good point, we can define these.

   UInt - UInt = SInt
      ...

   cmem vs reg of vec?
      reg of vec has initialization, and can be accessed combinationally
      maybe

   subword updates?
      modeled through the bundle types
      not supported, but need to figure out how to support it

   printfs and asserts

   all primops require same widths. Need explicit incrementer node.

   add padTo