DependencyStorage status busy is now implemented in registers instead…

… of Mem

src/main/scala/naxriscv/frontend/RfDependencyPlugin.scala

@@ -64,28 +64,15 @@ class DependencyStorage(physDepth : Int,
  }
 
  val status = new Area{
- val busy = Mem.fill(physDepth)(Bool())
- val write = for(p <- io.writes){
- busy.write(
- address = p.physical,
- data = True,
- enable = p.valid
- )
- }
- val commit = for(p <- io.commits) yield new Area{
- when(p.valid){
- busy.write(
- address = p.physical,
- data = False,
- enable = p.valid
- )
- }
- }
+ val busy = Reg(Bits(physDepth bits))
+ val sets = io.writes.map(e => UIntToOh(e.physical).andMask(e.valid)).reduceBalancedTree(_ | _)
+ val clears = io.commits.map(e => UIntToOh(e.physical).andMask(e.valid)).reduceBalancedTree(_ | _)
+ busy := (busy & ~clears) | sets
  }
 
  val read = for(p <- io.reads) yield new Area{
  val robId = translation.physToRob.readAsync(p.cmd.payload)
- val enabled = status.busy.readAsync(p.cmd.payload) //TODO as it was optimize, maybe we do not need the [dispatch] stage anymore in the frontend plugin
+ val enabled = status.busy(p.cmd.payload) //TODO as it was optimize, maybe we do not need the [dispatch] stage anymore in the frontend plugin
  p.rsp.valid := p.cmd.valid
  p.rsp.enable := enabled
  p.rsp.rob := robId