xref: /XiangShan/src/main/scala/xiangshan/frontend/PreDecode.scala (revision cf7d6b7a1a781c73aeb87de112de2e7fe5ea3b7c)

/***************************************************************************************
* 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 chisel3._
import chisel3.util
import chisel3.util._
import freechips.rocketchip.rocket.ExpandedInstruction
import freechips.rocketchip.rocket.RVCDecoder
import java.lang.reflect.Parameter
import org.chipsalliance.cde.config.Parameters
import utility._
import utils._
import xiangshan._
import xiangshan.backend.decode.isa.predecode.PreDecodeInst
import xiangshan.backend.fu.NewCSR.TriggerUtil
import xiangshan.backend.fu.util.SdtrigExt
import xiangshan.frontend.icache._

trait HasPdConst extends HasXSParameter with HasICacheParameters with HasIFUConst {
  def isRVC(inst: UInt) = inst(1, 0) =/= 3.U
  def isLink(reg: UInt) = reg === 1.U || reg === 5.U
  def brInfo(instr: UInt) = {
    val brType :: Nil = ListLookup(instr, List(BrType.notCFI), PreDecodeInst.brTable)
    val rd            = Mux(isRVC(instr), instr(12), instr(11, 7))
    val rs            = Mux(isRVC(instr), Mux(brType === BrType.jal, 0.U, instr(11, 7)), instr(19, 15))
    val isCall = (brType === BrType.jal && !isRVC(instr) || brType === BrType.jalr) && isLink(rd) // Only for RV64
    val isRet  = brType === BrType.jalr && isLink(rs) && !isCall
    List(brType, isCall, isRet)
  }
  def jal_offset(inst: UInt, rvc: Bool): UInt = {
    val rvc_offset = Cat(inst(12), inst(8), inst(10, 9), inst(6), inst(7), inst(2), inst(11), inst(5, 3), 0.U(1.W))
    val rvi_offset = Cat(inst(31), inst(19, 12), inst(20), inst(30, 21), 0.U(1.W))
    val max_width  = rvi_offset.getWidth
    SignExt(Mux(rvc, SignExt(rvc_offset, max_width), SignExt(rvi_offset, max_width)), XLEN)
  }
  def br_offset(inst: UInt, rvc: Bool): UInt = {
    val rvc_offset = Cat(inst(12), inst(6, 5), inst(2), inst(11, 10), inst(4, 3), 0.U(1.W))
    val rvi_offset = Cat(inst(31), inst(7), inst(30, 25), inst(11, 8), 0.U(1.W))
    val max_width  = rvi_offset.getWidth
    SignExt(Mux(rvc, SignExt(rvc_offset, max_width), SignExt(rvi_offset, max_width)), XLEN)
  }

  def NOP = "h4501".U(16.W)
}

object BrType {
  def notCFI  = "b00".U
  def branch  = "b01".U
  def jal     = "b10".U
  def jalr    = "b11".U
  def apply() = UInt(2.W)
}

object ExcType { // TODO:add exctype
  def notExc  = "b000".U
  def apply() = UInt(3.W)
}

class PreDecodeInfo extends Bundle { // 8 bit
  val valid  = Bool()
  val isRVC  = Bool()
  val brType = UInt(2.W)
  val isCall = Bool()
  val isRet  = Bool()
  // val excType = UInt(3.W)
  def isBr   = brType === BrType.branch
  def isJal  = brType === BrType.jal
  def isJalr = brType === BrType.jalr
  def notCFI = brType === BrType.notCFI
}

class PreDecodeResp(implicit p: Parameters) extends XSBundle with HasPdConst {
  val pd           = Vec(PredictWidth, new PreDecodeInfo)
  val hasHalfValid = Vec(PredictWidth, Bool())
  // val expInstr = Vec(PredictWidth, UInt(32.W))
  val instr      = Vec(PredictWidth, UInt(32.W))
  val jumpOffset = Vec(PredictWidth, UInt(XLEN.W))
//  val hasLastHalf = Bool()
  val triggered = Vec(PredictWidth, TriggerAction())
}

class PreDecode(implicit p: Parameters) extends XSModule with HasPdConst {
  val io = IO(new Bundle() {
    val in  = Input(ValidIO(new IfuToPreDecode))
    val out = Output(new PreDecodeResp)
  })

  val data = io.in.bits.data
//  val lastHalfMatch = io.in.lastHalfMatch
  val validStart, validEnd     = Wire(Vec(PredictWidth, Bool()))
  val h_validStart, h_validEnd = Wire(Vec(PredictWidth, Bool()))

  val validStart_half, validEnd_half     = Wire(Vec(PredictWidth, Bool()))
  val h_validStart_half, h_validEnd_half = Wire(Vec(PredictWidth, Bool()))

  val validStart_halfPlus1, validEnd_halfPlus1     = Wire(Vec(PredictWidth, Bool()))
  val h_validStart_halfPlus1, h_validEnd_halfPlus1 = Wire(Vec(PredictWidth, Bool()))

  val validStart_diff, validEnd_diff     = Wire(Vec(PredictWidth, Bool()))
  val h_validStart_diff, h_validEnd_diff = Wire(Vec(PredictWidth, Bool()))

  val currentIsRVC = Wire(Vec(PredictWidth, Bool()))

  validStart_half.map(_ := false.B)
  validEnd_half.map(_ := false.B)
  h_validStart_half.map(_ := false.B)
  h_validEnd_half.map(_ := false.B)

  validStart_halfPlus1.map(_ := false.B)
  validEnd_halfPlus1.map(_ := false.B)
  h_validStart_halfPlus1.map(_ := false.B)
  h_validEnd_halfPlus1.map(_ := false.B)

  val rawInsts = if (HasCExtension) VecInit((0 until PredictWidth).map(i => Cat(data(i + 1), data(i))))
  else VecInit((0 until PredictWidth).map(i => data(i)))

  for (i <- 0 until PredictWidth) {
    val inst = WireInit(rawInsts(i))
    // val expander       = Module(new RVCExpander)
    currentIsRVC(i) := isRVC(inst)
    val currentPC = io.in.bits.pc(i)
    // expander.io.in             := inst

    val brType :: isCall :: isRet :: Nil = brInfo(inst)
    val jalOffset                        = jal_offset(inst, currentIsRVC(i))
    val brOffset                         = br_offset(inst, currentIsRVC(i))

    io.out.hasHalfValid(i) := h_validStart(i)

    io.out.triggered(i) := DontCare // VecInit(Seq.fill(10)(false.B))

    io.out.pd(i).valid := validStart(i)
    io.out.pd(i).isRVC := currentIsRVC(i)

    // for diff purpose only
    io.out.pd(i).brType := brType
    io.out.pd(i).isCall := isCall
    io.out.pd(i).isRet  := isRet

    // io.out.expInstr(i)         := expander.io.out.bits
    io.out.instr(i)      := inst
    io.out.jumpOffset(i) := Mux(io.out.pd(i).isBr, brOffset, jalOffset)
  }

  // the first half is always reliable
  for (i <- 0 until PredictWidth / 2) {
    val lastIsValidEnd = if (i == 0) { true.B }
    else { validEnd(i - 1) || !HasCExtension.B }
    validStart(i) := (lastIsValidEnd || !HasCExtension.B)
    validEnd(i)   := validStart(i) && currentIsRVC(i) || !validStart(i) || !HasCExtension.B

    // prepared for last half match
    val h_lastIsValidEnd = if (i == 0) { false.B }
    else { h_validEnd(i - 1) || !HasCExtension.B }
    h_validStart(i) := (h_lastIsValidEnd || !HasCExtension.B)
    h_validEnd(i)   := h_validStart(i) && currentIsRVC(i) || !h_validStart(i) || !HasCExtension.B
  }

  for (i <- 0 until PredictWidth) {
    val lastIsValidEnd = if (i == 0) { true.B }
    else { validEnd_diff(i - 1) || !HasCExtension.B }
    validStart_diff(i) := (lastIsValidEnd || !HasCExtension.B)
    validEnd_diff(i)   := validStart_diff(i) && currentIsRVC(i) || !validStart_diff(i) || !HasCExtension.B

    // prepared for last half match
    val h_lastIsValidEnd = if (i == 0) { false.B }
    else { h_validEnd_diff(i - 1) || !HasCExtension.B }
    h_validStart_diff(i) := (h_lastIsValidEnd || !HasCExtension.B)
    h_validEnd_diff(i)   := h_validStart_diff(i) && currentIsRVC(i) || !h_validStart_diff(i) || !HasCExtension.B
  }

  // assume PredictWidth / 2 is a valid start
  for (i <- PredictWidth / 2 until PredictWidth) {
    val lastIsValidEnd = if (i == PredictWidth / 2) { true.B }
    else { validEnd_half(i - 1) || !HasCExtension.B }
    validStart_half(i) := (lastIsValidEnd || !HasCExtension.B)
    validEnd_half(i)   := validStart_half(i) && currentIsRVC(i) || !validStart_half(i) || !HasCExtension.B

    // prepared for last half match
    val h_lastIsValidEnd = if (i == PredictWidth / 2) { true.B }
    else { h_validEnd_half(i - 1) || !HasCExtension.B }
    h_validStart_half(i) := (h_lastIsValidEnd || !HasCExtension.B)
    h_validEnd_half(i)   := h_validStart_half(i) && currentIsRVC(i) || !h_validStart_half(i) || !HasCExtension.B
  }

  // assume PredictWidth / 2 + 1 is a valid start (and PredictWidth / 2 is last half of RVI)
  for (i <- PredictWidth / 2 + 1 until PredictWidth) {
    val lastIsValidEnd = if (i == PredictWidth / 2 + 1) { true.B }
    else { validEnd_halfPlus1(i - 1) || !HasCExtension.B }
    validStart_halfPlus1(i) := (lastIsValidEnd || !HasCExtension.B)
    validEnd_halfPlus1(i) := validStart_halfPlus1(i) && currentIsRVC(i) || !validStart_halfPlus1(i) || !HasCExtension.B

    // prepared for last half match
    val h_lastIsValidEnd = if (i == PredictWidth / 2 + 1) { true.B }
    else { h_validEnd_halfPlus1(i - 1) || !HasCExtension.B }
    h_validStart_halfPlus1(i) := (h_lastIsValidEnd || !HasCExtension.B)
    h_validEnd_halfPlus1(i) := h_validStart_halfPlus1(i) && currentIsRVC(i) || !h_validStart_halfPlus1(
      i
    ) || !HasCExtension.B
  }
  validStart_halfPlus1(PredictWidth / 2) := false.B // could be true but when true we select half, not halfPlus1
  validEnd_halfPlus1(PredictWidth / 2)   := true.B

  // assume h_PredictWidth / 2 is an end
  h_validStart_halfPlus1(PredictWidth / 2) := false.B // could be true but when true we select half, not halfPlus1
  h_validEnd_halfPlus1(PredictWidth / 2)   := true.B

  // if PredictWidth / 2 - 1 is a valid end, PredictWidth / 2 is a valid start
  for (i <- PredictWidth / 2 until PredictWidth) {
    validStart(i)   := Mux(validEnd(PredictWidth / 2 - 1), validStart_half(i), validStart_halfPlus1(i))
    validEnd(i)     := Mux(validEnd(PredictWidth / 2 - 1), validEnd_half(i), validEnd_halfPlus1(i))
    h_validStart(i) := Mux(h_validEnd(PredictWidth / 2 - 1), h_validStart_half(i), h_validStart_halfPlus1(i))
    h_validEnd(i)   := Mux(h_validEnd(PredictWidth / 2 - 1), h_validEnd_half(i), h_validEnd_halfPlus1(i))
  }

  val validStartMismatch        = Wire(Bool())
  val validEndMismatch          = Wire(Bool())
  val validH_ValidStartMismatch = Wire(Bool())
  val validH_ValidEndMismatch   = Wire(Bool())

  validStartMismatch        := validStart.zip(validStart_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
  validEndMismatch          := validEnd.zip(validEnd_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
  validH_ValidStartMismatch := h_validStart.zip(h_validStart_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
  validH_ValidEndMismatch   := h_validEnd.zip(h_validEnd_diff).map { case (a, b) => a =/= b }.reduce(_ || _)

  XSError(io.in.valid && validStartMismatch, p"validStart mismatch\n")
  XSError(io.in.valid && validEndMismatch, p"validEnd mismatch\n")
  XSError(io.in.valid && validH_ValidStartMismatch, p"h_validStart mismatch\n")
  XSError(io.in.valid && validH_ValidEndMismatch, p"h_validEnd mismatch\n")

//  io.out.hasLastHalf := !io.out.pd(PredictWidth - 1).isRVC && io.out.pd(PredictWidth - 1).valid

  for (i <- 0 until PredictWidth) {
    XSDebug(
      true.B,
      p"instr ${Hexadecimal(io.out.instr(i))}, " +
        p"validStart ${Binary(validStart(i))}, " +
        p"validEnd ${Binary(validEnd(i))}, " +
        p"isRVC ${Binary(io.out.pd(i).isRVC)}, " +
        p"brType ${Binary(io.out.pd(i).brType)}, " +
        p"isRet ${Binary(io.out.pd(i).isRet)}, " +
        p"isCall ${Binary(io.out.pd(i).isCall)}\n"
    )
  }
}

class IfuToF3PreDecode(implicit p: Parameters) extends XSBundle with HasPdConst {
  val instr = Vec(PredictWidth, UInt(32.W))
}

class F3PreDecodeResp(implicit p: Parameters) extends XSBundle with HasPdConst {
  val pd = Vec(PredictWidth, new PreDecodeInfo)
}
class F3Predecoder(implicit p: Parameters) extends XSModule with HasPdConst {
  val io = IO(new Bundle() {
    val in  = Input(new IfuToF3PreDecode)
    val out = Output(new F3PreDecodeResp)
  })
  io.out.pd.zipWithIndex.map { case (pd, i) =>
    pd.valid  := DontCare
    pd.isRVC  := DontCare
    pd.brType := brInfo(io.in.instr(i))(0)
    pd.isCall := brInfo(io.in.instr(i))(1)
    pd.isRet  := brInfo(io.in.instr(i))(2)
  }

}

class RVCExpander(implicit p: Parameters) extends XSModule {
  val io = IO(new Bundle {
    val in  = Input(UInt(32.W))
    val out = Output(new ExpandedInstruction)
    val ill = Output(Bool())
  })

  val decoder = new RVCDecoder(io.in, XLEN, fLen, useAddiForMv = true)

  if (HasCExtension) {
    io.out := decoder.decode
    io.ill := decoder.ill
  } else {
    io.out := decoder.passthrough
    io.ill := false.B
  }
}

/* ---------------------------------------------------------------------
 * Predict result check
 *
 * ---------------------------------------------------------------------
 */

object FaultType {
  def noFault      = "b000".U
  def jalFault     = "b001".U // not CFI taken or invalid instruction taken
  def retFault     = "b010".U // not CFI taken or invalid instruction taken
  def targetFault  = "b011".U
  def notCFIFault  = "b100".U // not CFI taken or invalid instruction taken
  def invalidTaken = "b101".U
  def apply()      = UInt(3.W)
}

class CheckInfo extends Bundle { // 8 bit
  val value             = UInt(3.W)
  def isjalFault        = value === FaultType.jalFault
  def isRetFault        = value === FaultType.retFault
  def istargetFault     = value === FaultType.targetFault
  def invalidTakenFault = value === FaultType.invalidTaken
  def notCFIFault       = value === FaultType.notCFIFault
}

class PredCheckerResp(implicit p: Parameters) extends XSBundle with HasPdConst {
  // to Ibuffer write port  (stage 1)
  val stage1Out = new Bundle {
    val fixedRange = Vec(PredictWidth, Bool())
    val fixedTaken = Vec(PredictWidth, Bool())
  }
  // to Ftq write back port (stage 2)
  val stage2Out = new Bundle {
    val fixedTarget   = Vec(PredictWidth, UInt(VAddrBits.W))
    val jalTarget     = Vec(PredictWidth, UInt(VAddrBits.W))
    val fixedMissPred = Vec(PredictWidth, Bool())
    val faultType     = Vec(PredictWidth, new CheckInfo)
  }
}

class PredChecker(implicit p: Parameters) extends XSModule with HasPdConst {
  val io = IO(new Bundle {
    val in  = Input(new IfuToPredChecker)
    val out = Output(new PredCheckerResp)
  })

  val (takenIdx, predTaken)    = (io.in.ftqOffset.bits, io.in.ftqOffset.valid)
  val predTarget               = io.in.target
  val (instrRange, instrValid) = (io.in.instrRange, io.in.instrValid)
  val (pds, pc, jumpOffset)    = (io.in.pds, io.in.pc, io.in.jumpOffset)

  val jalFaultVec, retFaultVec, targetFault, notCFITaken, invalidTaken = Wire(Vec(PredictWidth, Bool()))

  /** remask fault may appear together with other faults, but other faults are exclusive
    * so other f ault mast use fixed mask to keep only one fault would be found and redirect to Ftq
    * we first detecct remask fault and then use fixedRange to do second check
    **/

  // Stage 1: detect remask fault
  /** first check: remask Fault */
  jalFaultVec := VecInit(pds.zipWithIndex.map { case (pd, i) =>
    pd.isJal && instrRange(i) && instrValid(i) && (takenIdx > i.U && predTaken || !predTaken)
  })
  retFaultVec := VecInit(pds.zipWithIndex.map { case (pd, i) =>
    pd.isRet && instrRange(i) && instrValid(i) && (takenIdx > i.U && predTaken || !predTaken)
  })
  val remaskFault = VecInit((0 until PredictWidth).map(i => jalFaultVec(i) || retFaultVec(i)))
  val remaskIdx   = ParallelPriorityEncoder(remaskFault.asUInt)
  val needRemask  = ParallelOR(remaskFault)
  val fixedRange  = instrRange.asUInt & (Fill(PredictWidth, !needRemask) | Fill(PredictWidth, 1.U(1.W)) >> ~remaskIdx)

  io.out.stage1Out.fixedRange := fixedRange.asTypeOf(Vec(PredictWidth, Bool()))

  io.out.stage1Out.fixedTaken := VecInit(pds.zipWithIndex.map { case (pd, i) =>
    instrValid(i) && fixedRange(i) && (pd.isRet || pd.isJal || takenIdx === i.U && predTaken && !pd.notCFI)
  })

  /** second check: faulse prediction fault and target fault */
  notCFITaken := VecInit(pds.zipWithIndex.map { case (pd, i) =>
    fixedRange(i) && instrValid(i) && i.U === takenIdx && pd.notCFI && predTaken
  })
  invalidTaken := VecInit(pds.zipWithIndex.map { case (pd, i) =>
    fixedRange(i) && !instrValid(i) && i.U === takenIdx && predTaken
  })

  val jumpTargets = VecInit(pds.zipWithIndex.map { case (pd, i) =>
    (pc(i) + jumpOffset(i)).asTypeOf(UInt(VAddrBits.W))
  })
  val seqTargets = VecInit((0 until PredictWidth).map(i => pc(i) + Mux(pds(i).isRVC || !instrValid(i), 2.U, 4.U)))

  // Stage 2: detect target fault
  /** target calculation: in the next stage  */
  val fixedRangeNext   = RegEnable(fixedRange, io.in.fire_in)
  val instrValidNext   = RegEnable(instrValid, io.in.fire_in)
  val takenIdxNext     = RegEnable(takenIdx, io.in.fire_in)
  val predTakenNext    = RegEnable(predTaken, io.in.fire_in)
  val predTargetNext   = RegEnable(predTarget, io.in.fire_in)
  val jumpTargetsNext  = RegEnable(jumpTargets, io.in.fire_in)
  val seqTargetsNext   = RegEnable(seqTargets, io.in.fire_in)
  val pdsNext          = RegEnable(pds, io.in.fire_in)
  val jalFaultVecNext  = RegEnable(jalFaultVec, io.in.fire_in)
  val retFaultVecNext  = RegEnable(retFaultVec, io.in.fire_in)
  val notCFITakenNext  = RegEnable(notCFITaken, io.in.fire_in)
  val invalidTakenNext = RegEnable(invalidTaken, io.in.fire_in)

  targetFault := VecInit(pdsNext.zipWithIndex.map { case (pd, i) =>
    fixedRangeNext(i) && instrValidNext(
      i
    ) && (pd.isJal || pd.isBr) && takenIdxNext === i.U && predTakenNext && (predTargetNext =/= jumpTargetsNext(i))
  })

  io.out.stage2Out.faultType.zipWithIndex.foreach { case (faultType, i) =>
    faultType.value := Mux(
      jalFaultVecNext(i),
      FaultType.jalFault,
      Mux(
        retFaultVecNext(i),
        FaultType.retFault,
        Mux(
          targetFault(i),
          FaultType.targetFault,
          Mux(
            notCFITakenNext(i),
            FaultType.notCFIFault,
            Mux(invalidTakenNext(i), FaultType.invalidTaken, FaultType.noFault)
          )
        )
      )
    )
  }

  io.out.stage2Out.fixedMissPred.zipWithIndex.foreach { case (missPred, i) =>
    missPred := jalFaultVecNext(i) || retFaultVecNext(i) || notCFITakenNext(i) || invalidTakenNext(i) || targetFault(i)
  }
  io.out.stage2Out.fixedTarget.zipWithIndex.foreach { case (target, i) =>
    target := Mux(jalFaultVecNext(i) || targetFault(i), jumpTargetsNext(i), seqTargetsNext(i))
  }
  io.out.stage2Out.jalTarget.zipWithIndex.foreach { case (target, i) => target := jumpTargetsNext(i) }

}

class FrontendTrigger(implicit p: Parameters) extends XSModule with SdtrigExt {
  val io = IO(new Bundle() {
    val frontendTrigger = Input(new FrontendTdataDistributeIO)
    val triggered       = Output(Vec(PredictWidth, TriggerAction()))

    val pds = Input(Vec(PredictWidth, new PreDecodeInfo))
    val pc  = Input(Vec(PredictWidth, UInt(VAddrBits.W)))
    val data = if (HasCExtension) Input(Vec(PredictWidth + 1, UInt(16.W)))
    else Input(Vec(PredictWidth, UInt(32.W)))
  })

  val data = io.data

  val rawInsts = if (HasCExtension) VecInit((0 until PredictWidth).map(i => Cat(data(i + 1), data(i))))
  else VecInit((0 until PredictWidth).map(i => data(i)))

  val tdataVec = RegInit(VecInit(Seq.fill(TriggerNum)(0.U.asTypeOf(new MatchTriggerIO))))
  when(io.frontendTrigger.tUpdate.valid) {
    tdataVec(io.frontendTrigger.tUpdate.bits.addr) := io.frontendTrigger.tUpdate.bits.tdata
  }
  val triggerEnableVec = RegInit(VecInit(Seq.fill(TriggerNum)(false.B))) // From CSR, controlled by priv mode, etc.
  triggerEnableVec := io.frontendTrigger.tEnableVec
  XSDebug(triggerEnableVec.asUInt.orR, "Debug Mode: At least one frontend trigger is enabled\n")

  val triggerTimingVec = VecInit(tdataVec.map(_.timing))
  val triggerChainVec  = VecInit(tdataVec.map(_.chain))

  for (i <- 0 until TriggerNum) { PrintTriggerInfo(triggerEnableVec(i), tdataVec(i)) }

  val debugMode            = io.frontendTrigger.debugMode
  val triggerCanRaiseBpExp = io.frontendTrigger.triggerCanRaiseBpExp
  // val triggerHitVec = Wire(Vec(PredictWidth, Vec(TriggerNum, Bool())))
  val triggerHitVec = (0 until TriggerNum).map(j =>
    TriggerCmpConsecutive(io.pc, tdataVec(j).tdata2, tdataVec(j).matchType, triggerEnableVec(j)).map(hit =>
      hit && !tdataVec(j).select && !debugMode
    )
  ).transpose

  for (i <- 0 until PredictWidth) {
    val triggerCanFireVec = Wire(Vec(TriggerNum, Bool()))
    TriggerCheckCanFire(TriggerNum, triggerCanFireVec, VecInit(triggerHitVec(i)), triggerTimingVec, triggerChainVec)

    val actionVec     = VecInit(tdataVec.map(_.action))
    val triggerAction = Wire(TriggerAction())
    TriggerUtil.triggerActionGen(triggerAction, triggerCanFireVec, actionVec, triggerCanRaiseBpExp)

    // Priority may select last when no trigger fire.
    io.triggered(i) := triggerAction
    XSDebug(
      triggerCanFireVec.asUInt.orR,
      p"Debug Mode: Predecode Inst No. ${i} has trigger action vec ${triggerCanFireVec.asUInt.orR}\n"
    )
  }
}