Carry Select Adder Scala Chisel - scala

Question

I'm trying to implement a Carry Select Adder using Chisel in Scala. However after various efforts i keep getting errors. The ripple carry adder and multiplexers are tested and working. This is my current Version. Any Input is greatly appreciated!
class CarrySelectAdder(val n:Int, val m:Int) extends Module {
val io = IO(new Bundle {
val a = Input(UInt(n.W))
val b = Input(UInt(n.W))
val cin = Input(UInt(1.W))
val sum = Output(UInt((n+1).W))
})
object carryselecthelper{ //not used atm
def n_sum_idx(stage:UInt) : UInt = {
return stage * (stage + 1.U) / 2.U;
}
}
//val test = math.ceil(n/m)
val rcas = Array.fill(2 * (n/m)){Module(new RcaAdder(m)).io} //2*math.ceil(n/m)
val muxs = Array.fill(n/m){Module(new Multiplexer(m+1)).io} //math.ceil(n/m)
val Sum = Wire(Vec(n, Bool()))
for (i <- 0 until n) {
rcas(i*2).a := io.a.apply(i*m+m,i*m)
rcas(i*2).b := io.b.apply(i*m+m,i*m)
rcas(i*2).cin := 0.asUInt
rcas(2*i+1).a := io.a.apply(i*m+m,i*m)
rcas(2*i+1).b := io.b.apply(i*m+m,i*m)
rcas(2*i+1).cin := 1.asUInt
muxs(i).a := rcas(i*2).sum
muxs(i).b := rcas(2*i+1).sum
if(i > 0){
muxs(i).sel := io.cin
}
if(i > 0){
if(muxs(i).sel == 0){
muxs(i).sel := rcas(2*i).cout
}else{
muxs(i).sel := rcas(2*i+1).cout
}
}
Sum(i) := muxs(i).out
}
io.sum := Sum.asUInt
}
Currently I'm getting an Exception in "ChiselGeneratorAnnotation":
l3.internal.ChiselException: Exception thrown when elaborating ChiselGeneratorAnnotation
at chisel3.stage.ChiselGeneratorAnnotation.elaborate(ChiselAnnotations.scala:55)
ChiselAnnotations.scala:55
at chisel3.stage.phases.Elaborate.$anonfun$transform$1(Elaborate.scala:19)
Elaborate.scala:19
at scala.collection.TraversableLike.$anonfun$flatMap$1(TraversableLike.scala:245)
TraversableLike.scala:245
at scala.collection.immutable.List.foreach(List.scala:392)
List.scala:392
at scala.collection.TraversableLike.flatMap(TraversableLike.scala:245)
TraversableLike.scala:245
at scala.collection.TraversableLike.flatMap$(TraversableLike.scala:242)
TraversableLike.scala:242
at scala.collection.immutable.List.flatMap(List.scala:355)
List.scala:355
at chisel3.stage.phases.Elaborate.transform(Elaborate.scala:18)
Elaborate.scala:18
at chisel3.iotesters.setupTreadleBackend$.apply(TreadleBackend.scala:143)
TreadleBackend.scala:143
at chisel3.iotesters.Driver$.$anonfun$execute$2(Driver.scala:53)
Driver.scala:53
at scala.runtime.java8.JFunction0$mcZ$sp.apply(JFunction0$mcZ$sp.java:23)
at logger.Logger$.$anonfun$makeScope$2(Logger.scala:168)
Logger.scala:168
at scala.util.DynamicVariable.withValue(DynamicVariable.scala:62)
DynamicVariable.scala:62
at logger.Logger$.makeScope(Logger.scala:166)
Logger.scala:166
at logger.Logger$.makeScope(Logger.scala:127)
Logger.scala:127
at chisel3.iotesters.Driver$.$anonfun$execute$1(Driver.scala:38)
Driver.scala:38
at scala.runtime.java8.JFunction0$mcZ$sp.apply(JFunction0$mcZ$sp.java:23)
at scala.util.DynamicVariable.withValue(DynamicVariable.scala:62)
DynamicVariable.scala:62
at chisel3.iotesters.Driver$.execute(Driver.scala:38)
Driver.scala:38
Upon request I added the Multiplexer and RCA class, they should work fine, since they ran all tests without issues. Thanks!
class Multiplexer(val n:Int) extends Module {
val io = IO(new Bundle {
val a = Input(UInt(n.W))
val b = Input(UInt(n.W))
val sel = Input(UInt(n.W))
val out = Output(UInt(n.W))
})
io.out := (io.sel & io.a) | (~io.sel & io.b)
}
class RcaAdder(val n:Int) extends Module {
val io = IO(new Bundle {
val a = Input(UInt(n.W))
val b = Input(UInt(n.W))
val cin = Input(UInt(1.W))
val sum = Output(UInt(n.W))
val cout = Output(UInt(1.W))
})
val FAs = Array.fill(n){Module(new FullAdder()).io}
val carry = Wire(Vec(n+1, UInt(1.W)))
val sum = Wire(Vec(n, Bool()))
carry(0) := io.cin
for (i <- 0 until n) {
FAs(i).a := io.a(i)
FAs(i).b := io.b(i)
FAs(i).cin := carry(i)
carry(i+1) := FAs(i).cout
sum(i) := FAs(i).sum.asBool
}
io.sum := sum.asUInt
io.cout := carry(n)
}
(This is what is used to test the code.)
class CarrySelectAdderTester(dut: CarrySelectAdder, n: Int) extends PeekPokeTester(dut) {
val max=scala.math.pow(2,n).toInt-1
for(i <- 0 to max){
for (j <- 0 to max){
for (k <- 0 to 1){
poke(dut.io.a,i)
poke(dut.io.b,j)
poke(dut.io.cin,k)
step(100)
expect(dut.io.sum,(i+j+k))
}
}
}
}
object CarrySelectAdderTester extends App{
val bitWidth=6
val bitsperblock=3
println("Testing the Carry Select Adder")
iotesters.Driver.execute(Array[String](), () => new CarrySelectAdder(bitWidth, bitsperblock)){
c => new CarrySelectAdderTester(c,bitWidth)
}
}