package utils

import chisel3._

import chisel3.util._

object ParallelOperation {

  def apply[T](xs: Seq[T], func: (T, T) => T): T = {

    require(xs.nonEmpty)

    xs match {

      case Seq(a) => a

      case Seq(a, b) => func(a, b)

      case _ =>

        apply(Seq(apply(xs take xs.size/2, func), apply(xs drop xs.size/2, func)), func)

    }

  }

}

object ParallelOR {

  def apply[T <: Data](xs: Seq[T]): T = {

    ParallelOperation(xs, (a: T, b: T) => (a.asUInt | b.asUInt).asTypeOf(xs.head))

  }

}

object LowerMask {

  def apply(a: UInt, len: Int): UInt = {

    ParallelOR((0 until len).map(i => (a >> i).asUInt))

  }

  def apply(a: UInt): UInt = {

    apply(a, a.getWidth)

  }

}

 val s2_allocatableSlots = VecInit(s2_resps.map(r => !r.valid && !r.bits.u)).asUInt &  //5 bits

    ~(LowerMask(UIntToOH(s2_provider), ITTageNTables) & Fill(ITTageNTables, s2_provided.asUInt))