/***************************************************************************************
* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
* Copyright (c) 2020-2021 Peng Cheng Laboratory
*
* XiangShan is licensed under Mulan PSL v2.
* You can use this software according to the terms and conditions of the Mulan PSL v2.
* You may obtain a copy of Mulan PSL v2 at:
*          http://license.coscl.org.cn/MulanPSL2
*
* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
*
* See the Mulan PSL v2 for more details.
***************************************************************************************/

package xiangshan.frontend

import chipsalliance.rocketchip.config.Parameters
import chisel3._
import chisel3.util._
import chisel3.experimental.chiselName
import xiangshan._
import utils._

@chiselName
class Composer(implicit p: Parameters) extends BasePredictor with HasBPUConst {
  val (components, resp) = getBPDComponents(io.in.bits.resp_in(0), p)
  io.out.resp := resp

  var metas = 0.U(1.W)
  var meta_sz = 0
  for (c <- components) {
    c.io.in.valid            := io.in.valid
    c.io.in.bits.s0_pc       := io.in.bits.s0_pc
    c.io.in.bits.folded_hist := io.in.bits.folded_hist
    c.io.in.bits.phist       := io.in.bits.phist

    c.io.s0_fire := io.s0_fire
    c.io.s1_fire := io.s1_fire
    c.io.s2_fire := io.s2_fire
    c.io.s3_fire := io.s3_fire

    c.io.redirect := io.redirect

    if (c.meta_size > 0) {
      metas = (metas << c.meta_size) | c.io.out.s3_meta(c.meta_size-1,0)
    }
    meta_sz = meta_sz + c.meta_size
  }
  println(s"total meta size: $meta_sz\n\n")

  io.in.ready := components.map(_.io.s1_ready).reduce(_ && _)

  io.s1_ready := components.map(_.io.s1_ready).reduce(_ && _)
  io.s2_ready := components.map(_.io.s2_ready).reduce(_ && _)
  io.s3_ready := components.map(_.io.s3_ready).reduce(_ && _)

  require(meta_sz < MaxMetaLength)
  io.out.s3_meta := metas

  var update_meta = io.update.bits.meta
  for (c <- components.reverse) {
    c.io.update := io.update
    c.io.update.bits.meta := update_meta
    update_meta = update_meta >> c.meta_size
  }

  def extractMeta(meta: UInt, idx: Int): UInt = {
    var update_meta = meta
    var metas: Seq[UInt] = Nil
    for (c <- components.reverse) {
      metas = metas :+ update_meta
      update_meta = update_meta >> c.meta_size
    }
    metas(idx)
  }

  override def getFoldedHistoryInfo = Some(components.map(_.getFoldedHistoryInfo.getOrElse(Set())).reduce(_++_))

  val comp_1_perf = components(1).asInstanceOf[MicroBTB].perfEvents.map(_._1).zip(components(1).asInstanceOf[MicroBTB].perfinfo.perfEvents.perf_events)
  val comp_2_perf = components(2).asInstanceOf[Tage_SC].perfEvents.map(_._1).zip(components(2).asInstanceOf[Tage_SC].perfinfo.perfEvents.perf_events)
  val comp_3_perf = components(3).asInstanceOf[FTB].perfEvents.map(_._1).zip(components(3).asInstanceOf[FTB].perfinfo.perfEvents.perf_events)
  val perfEvents = comp_1_perf ++ comp_2_perf ++ comp_3_perf
  val perf_list = components(1).asInstanceOf[MicroBTB].perfinfo.perfEvents.perf_events ++
                  components(2).asInstanceOf[Tage_SC].perfinfo.perfEvents.perf_events ++
                  components(3).asInstanceOf[FTB].perfinfo.perfEvents.perf_events
  val perfinfo = IO(new Bundle(){
    val perfEvents = Output(new PerfEventsBundle(perf_list.length))
  })
  perfinfo.perfEvents.perf_events := perf_list
}