xref: /XiangShan/src/main/scala/xiangshan/frontend/PreDecode.scala (revision 7f475a241b2cdf869833f641138fdf66b32c9bd6)
109c6f1ddSLingrui98/***************************************************************************************
209c6f1ddSLingrui98* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
309c6f1ddSLingrui98* Copyright (c) 2020-2021 Peng Cheng Laboratory
409c6f1ddSLingrui98*
509c6f1ddSLingrui98* XiangShan is licensed under Mulan PSL v2.
609c6f1ddSLingrui98* You can use this software according to the terms and conditions of the Mulan PSL v2.
709c6f1ddSLingrui98* You may obtain a copy of Mulan PSL v2 at:
809c6f1ddSLingrui98*          http://license.coscl.org.cn/MulanPSL2
909c6f1ddSLingrui98*
1009c6f1ddSLingrui98* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
1109c6f1ddSLingrui98* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
1209c6f1ddSLingrui98* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
1309c6f1ddSLingrui98*
1409c6f1ddSLingrui98* See the Mulan PSL v2 for more details.
1509c6f1ddSLingrui98***************************************************************************************/
1609c6f1ddSLingrui98
1709c6f1ddSLingrui98package xiangshan.frontend
1809c6f1ddSLingrui98
19cf7d6b7aSMuziimport chisel3._
2009c6f1ddSLingrui98import chisel3.util._
21cf7d6b7aSMuziimport freechips.rocketchip.rocket.ExpandedInstruction
22cf7d6b7aSMuziimport freechips.rocketchip.rocket.RVCDecoder
23cf7d6b7aSMuziimport org.chipsalliance.cde.config.Parameters
243c02ee8fSwakafaimport utility._
25cf7d6b7aSMuziimport utils._
2609c6f1ddSLingrui98import xiangshan._
2709c6f1ddSLingrui98import xiangshan.backend.decode.isa.predecode.PreDecodeInst
287e0f64b0SGuanghui Chengimport xiangshan.backend.fu.NewCSR.TriggerUtil
29f7af4c74Schengguanghuiimport xiangshan.backend.fu.util.SdtrigExt
30cf7d6b7aSMuziimport xiangshan.frontend.icache._
3109c6f1ddSLingrui98
3209c6f1ddSLingrui98trait HasPdConst extends HasXSParameter with HasICacheParameters with HasIFUConst {
33cf7d6b7aSMuzi  def isRVC(inst: UInt) = inst(1, 0) =/= 3.U
3409c6f1ddSLingrui98  def isLink(reg: UInt) = reg === 1.U || reg === 5.U
3509c6f1ddSLingrui98  def brInfo(instr: UInt) = {
3609c6f1ddSLingrui98    val brType :: Nil = ListLookup(instr, List(BrType.notCFI), PreDecodeInst.brTable)
3709c6f1ddSLingrui98    val rd            = Mux(isRVC(instr), instr(12), instr(11, 7))
3809c6f1ddSLingrui98    val rs            = Mux(isRVC(instr), Mux(brType === BrType.jal, 0.U, instr(11, 7)), instr(19, 15))
3909c6f1ddSLingrui98    val isCall = (brType === BrType.jal && !isRVC(instr) || brType === BrType.jalr) && isLink(rd) // Only for RV64
4009c6f1ddSLingrui98    val isRet  = brType === BrType.jalr && isLink(rs) && !isCall
4109c6f1ddSLingrui98    List(brType, isCall, isRet)
4209c6f1ddSLingrui98  }
4309c6f1ddSLingrui98  def jal_offset(inst: UInt, rvc: Bool): UInt = {
4409c6f1ddSLingrui98    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))
4509c6f1ddSLingrui98    val rvi_offset = Cat(inst(31), inst(19, 12), inst(20), inst(30, 21), 0.U(1.W))
4609c6f1ddSLingrui98    val max_width  = rvi_offset.getWidth
4709c6f1ddSLingrui98    SignExt(Mux(rvc, SignExt(rvc_offset, max_width), SignExt(rvi_offset, max_width)), XLEN)
4809c6f1ddSLingrui98  }
4909c6f1ddSLingrui98  def br_offset(inst: UInt, rvc: Bool): UInt = {
5009c6f1ddSLingrui98    val rvc_offset = Cat(inst(12), inst(6, 5), inst(2), inst(11, 10), inst(4, 3), 0.U(1.W))
5109c6f1ddSLingrui98    val rvi_offset = Cat(inst(31), inst(7), inst(30, 25), inst(11, 8), 0.U(1.W))
5209c6f1ddSLingrui98    val max_width  = rvi_offset.getWidth
5309c6f1ddSLingrui98    SignExt(Mux(rvc, SignExt(rvc_offset, max_width), SignExt(rvi_offset, max_width)), XLEN)
5409c6f1ddSLingrui98  }
5509c6f1ddSLingrui98
5609c6f1ddSLingrui98  def NOP = "h4501".U(16.W)
5709c6f1ddSLingrui98}
5809c6f1ddSLingrui98
5909c6f1ddSLingrui98object BrType {
6009c6f1ddSLingrui98  def notCFI  = "b00".U
6109c6f1ddSLingrui98  def branch  = "b01".U
6209c6f1ddSLingrui98  def jal     = "b10".U
6309c6f1ddSLingrui98  def jalr    = "b11".U
6409c6f1ddSLingrui98  def apply() = UInt(2.W)
6509c6f1ddSLingrui98}
6609c6f1ddSLingrui98
6709c6f1ddSLingrui98object ExcType { // TODO:add exctype
6809c6f1ddSLingrui98  def notExc  = "b000".U
6909c6f1ddSLingrui98  def apply() = UInt(3.W)
7009c6f1ddSLingrui98}
7109c6f1ddSLingrui98
7209c6f1ddSLingrui98class PreDecodeInfo extends Bundle { // 8 bit
7309c6f1ddSLingrui98  val valid  = Bool()
7409c6f1ddSLingrui98  val isRVC  = Bool()
7509c6f1ddSLingrui98  val brType = UInt(2.W)
7609c6f1ddSLingrui98  val isCall = Bool()
7709c6f1ddSLingrui98  val isRet  = Bool()
7809c6f1ddSLingrui98  // val excType = UInt(3.W)
7909c6f1ddSLingrui98  def isBr   = brType === BrType.branch
8009c6f1ddSLingrui98  def isJal  = brType === BrType.jal
8109c6f1ddSLingrui98  def isJalr = brType === BrType.jalr
8209c6f1ddSLingrui98  def notCFI = brType === BrType.notCFI
8309c6f1ddSLingrui98}
8409c6f1ddSLingrui98
8509c6f1ddSLingrui98class PreDecodeResp(implicit p: Parameters) extends XSBundle with HasPdConst {
86a4e57ea3SLi Qianruo  val pd           = Vec(PredictWidth, new PreDecodeInfo)
87a4e57ea3SLi Qianruo  val hasHalfValid = Vec(PredictWidth, Bool())
8848a62719SJenius  // val expInstr = Vec(PredictWidth, UInt(32.W))
8948a62719SJenius  val instr      = Vec(PredictWidth, UInt(32.W))
90a4e57ea3SLi Qianruo  val jumpOffset = Vec(PredictWidth, UInt(XLEN.W))
91a4e57ea3SLi Qianruo//  val hasLastHalf = Bool()
927e0f64b0SGuanghui Cheng  val triggered = Vec(PredictWidth, TriggerAction())
9309c6f1ddSLingrui98}
9409c6f1ddSLingrui98
9509c6f1ddSLingrui98class PreDecode(implicit p: Parameters) extends XSModule with HasPdConst {
9609c6f1ddSLingrui98  val io = IO(new Bundle() {
979afa8a47STang Haojin    val in  = Input(ValidIO(new IfuToPreDecode))
9809c6f1ddSLingrui98    val out = Output(new PreDecodeResp)
9909c6f1ddSLingrui98  })
10009c6f1ddSLingrui98
1019afa8a47STang Haojin  val data = io.in.bits.data
102a4e57ea3SLi Qianruo//  val lastHalfMatch = io.in.lastHalfMatch
103a4e57ea3SLi Qianruo  val validStart, validEnd     = Wire(Vec(PredictWidth, Bool()))
104a4e57ea3SLi Qianruo  val h_validStart, h_validEnd = Wire(Vec(PredictWidth, Bool()))
10509c6f1ddSLingrui98
106330aad7fSGuokai Chen  val validStart_half, validEnd_half     = Wire(Vec(PredictWidth, Bool()))
107330aad7fSGuokai Chen  val h_validStart_half, h_validEnd_half = Wire(Vec(PredictWidth, Bool()))
108330aad7fSGuokai Chen
109330aad7fSGuokai Chen  val validStart_halfPlus1, validEnd_halfPlus1     = Wire(Vec(PredictWidth, Bool()))
110330aad7fSGuokai Chen  val h_validStart_halfPlus1, h_validEnd_halfPlus1 = Wire(Vec(PredictWidth, Bool()))
111330aad7fSGuokai Chen
112330aad7fSGuokai Chen  val validStart_diff, validEnd_diff     = Wire(Vec(PredictWidth, Bool()))
113330aad7fSGuokai Chen  val h_validStart_diff, h_validEnd_diff = Wire(Vec(PredictWidth, Bool()))
114330aad7fSGuokai Chen
115330aad7fSGuokai Chen  val currentIsRVC = Wire(Vec(PredictWidth, Bool()))
116330aad7fSGuokai Chen
117330aad7fSGuokai Chen  validStart_half.map(_ := false.B)
118330aad7fSGuokai Chen  validEnd_half.map(_ := false.B)
119330aad7fSGuokai Chen  h_validStart_half.map(_ := false.B)
120330aad7fSGuokai Chen  h_validEnd_half.map(_ := false.B)
121330aad7fSGuokai Chen
122330aad7fSGuokai Chen  validStart_halfPlus1.map(_ := false.B)
123330aad7fSGuokai Chen  validEnd_halfPlus1.map(_ := false.B)
124330aad7fSGuokai Chen  h_validStart_halfPlus1.map(_ := false.B)
125330aad7fSGuokai Chen  h_validEnd_halfPlus1.map(_ := false.B)
126330aad7fSGuokai Chen
12709c6f1ddSLingrui98  val rawInsts = if (HasCExtension) VecInit((0 until PredictWidth).map(i => Cat(data(i + 1), data(i))))
12809c6f1ddSLingrui98  else VecInit((0 until PredictWidth).map(i => data(i)))
12909c6f1ddSLingrui98
13009c6f1ddSLingrui98  for (i <- 0 until PredictWidth) {
131a4e57ea3SLi Qianruo    val inst = WireInit(rawInsts(i))
13248a62719SJenius    // val expander       = Module(new RVCExpander)
133330aad7fSGuokai Chen    currentIsRVC(i) := isRVC(inst)
1349afa8a47STang Haojin    val currentPC = io.in.bits.pc(i)
13548a62719SJenius    // expander.io.in             := inst
13609c6f1ddSLingrui98
13709c6f1ddSLingrui98    val brType :: isCall :: isRet :: Nil = brInfo(inst)
138330aad7fSGuokai Chen    val jalOffset                        = jal_offset(inst, currentIsRVC(i))
139330aad7fSGuokai Chen    val brOffset                         = br_offset(inst, currentIsRVC(i))
140a4e57ea3SLi Qianruo
141a4e57ea3SLi Qianruo    io.out.hasHalfValid(i) := h_validStart(i)
142a4e57ea3SLi Qianruo
143a4e57ea3SLi Qianruo    io.out.triggered(i) := DontCare // VecInit(Seq.fill(10)(false.B))
144a4e57ea3SLi Qianruo
145a4e57ea3SLi Qianruo    io.out.pd(i).valid := validStart(i)
146330aad7fSGuokai Chen    io.out.pd(i).isRVC := currentIsRVC(i)
147330aad7fSGuokai Chen
148330aad7fSGuokai Chen    // for diff purpose only
14909c6f1ddSLingrui98    io.out.pd(i).brType := brType
15009c6f1ddSLingrui98    io.out.pd(i).isCall := isCall
15109c6f1ddSLingrui98    io.out.pd(i).isRet  := isRet
152ddb65c47SLi Qianruo
15348a62719SJenius    // io.out.expInstr(i)         := expander.io.out.bits
15448a62719SJenius    io.out.instr(i)      := inst
155a4e57ea3SLi Qianruo    io.out.jumpOffset(i) := Mux(io.out.pd(i).isBr, brOffset, jalOffset)
15609c6f1ddSLingrui98  }
15709c6f1ddSLingrui98
158330aad7fSGuokai Chen  // the first half is always reliable
159330aad7fSGuokai Chen  for (i <- 0 until PredictWidth / 2) {
160cf7d6b7aSMuzi    val lastIsValidEnd = if (i == 0) { true.B }
161cf7d6b7aSMuzi    else { validEnd(i - 1) || !HasCExtension.B }
162330aad7fSGuokai Chen    validStart(i) := (lastIsValidEnd || !HasCExtension.B)
163330aad7fSGuokai Chen    validEnd(i)   := validStart(i) && currentIsRVC(i) || !validStart(i) || !HasCExtension.B
164330aad7fSGuokai Chen
165330aad7fSGuokai Chen    // prepared for last half match
166cf7d6b7aSMuzi    val h_lastIsValidEnd = if (i == 0) { false.B }
167cf7d6b7aSMuzi    else { h_validEnd(i - 1) || !HasCExtension.B }
168330aad7fSGuokai Chen    h_validStart(i) := (h_lastIsValidEnd || !HasCExtension.B)
169330aad7fSGuokai Chen    h_validEnd(i)   := h_validStart(i) && currentIsRVC(i) || !h_validStart(i) || !HasCExtension.B
170330aad7fSGuokai Chen  }
171330aad7fSGuokai Chen
172330aad7fSGuokai Chen  for (i <- 0 until PredictWidth) {
173cf7d6b7aSMuzi    val lastIsValidEnd = if (i == 0) { true.B }
174cf7d6b7aSMuzi    else { validEnd_diff(i - 1) || !HasCExtension.B }
175330aad7fSGuokai Chen    validStart_diff(i) := (lastIsValidEnd || !HasCExtension.B)
176330aad7fSGuokai Chen    validEnd_diff(i)   := validStart_diff(i) && currentIsRVC(i) || !validStart_diff(i) || !HasCExtension.B
177330aad7fSGuokai Chen
178330aad7fSGuokai Chen    // prepared for last half match
179cf7d6b7aSMuzi    val h_lastIsValidEnd = if (i == 0) { false.B }
180cf7d6b7aSMuzi    else { h_validEnd_diff(i - 1) || !HasCExtension.B }
181330aad7fSGuokai Chen    h_validStart_diff(i) := (h_lastIsValidEnd || !HasCExtension.B)
182330aad7fSGuokai Chen    h_validEnd_diff(i)   := h_validStart_diff(i) && currentIsRVC(i) || !h_validStart_diff(i) || !HasCExtension.B
183330aad7fSGuokai Chen  }
184330aad7fSGuokai Chen
185330aad7fSGuokai Chen  // assume PredictWidth / 2 is a valid start
186330aad7fSGuokai Chen  for (i <- PredictWidth / 2 until PredictWidth) {
187cf7d6b7aSMuzi    val lastIsValidEnd = if (i == PredictWidth / 2) { true.B }
188cf7d6b7aSMuzi    else { validEnd_half(i - 1) || !HasCExtension.B }
189330aad7fSGuokai Chen    validStart_half(i) := (lastIsValidEnd || !HasCExtension.B)
190330aad7fSGuokai Chen    validEnd_half(i)   := validStart_half(i) && currentIsRVC(i) || !validStart_half(i) || !HasCExtension.B
191330aad7fSGuokai Chen
192330aad7fSGuokai Chen    // prepared for last half match
193cf7d6b7aSMuzi    val h_lastIsValidEnd = if (i == PredictWidth / 2) { true.B }
194cf7d6b7aSMuzi    else { h_validEnd_half(i - 1) || !HasCExtension.B }
195330aad7fSGuokai Chen    h_validStart_half(i) := (h_lastIsValidEnd || !HasCExtension.B)
196330aad7fSGuokai Chen    h_validEnd_half(i)   := h_validStart_half(i) && currentIsRVC(i) || !h_validStart_half(i) || !HasCExtension.B
197330aad7fSGuokai Chen  }
198330aad7fSGuokai Chen
199330aad7fSGuokai Chen  // assume PredictWidth / 2 + 1 is a valid start (and PredictWidth / 2 is last half of RVI)
200330aad7fSGuokai Chen  for (i <- PredictWidth / 2 + 1 until PredictWidth) {
201cf7d6b7aSMuzi    val lastIsValidEnd = if (i == PredictWidth / 2 + 1) { true.B }
202cf7d6b7aSMuzi    else { validEnd_halfPlus1(i - 1) || !HasCExtension.B }
203330aad7fSGuokai Chen    validStart_halfPlus1(i) := (lastIsValidEnd || !HasCExtension.B)
204330aad7fSGuokai Chen    validEnd_halfPlus1(i) := validStart_halfPlus1(i) && currentIsRVC(i) || !validStart_halfPlus1(i) || !HasCExtension.B
205330aad7fSGuokai Chen
206330aad7fSGuokai Chen    // prepared for last half match
207cf7d6b7aSMuzi    val h_lastIsValidEnd = if (i == PredictWidth / 2 + 1) { true.B }
208cf7d6b7aSMuzi    else { h_validEnd_halfPlus1(i - 1) || !HasCExtension.B }
209330aad7fSGuokai Chen    h_validStart_halfPlus1(i) := (h_lastIsValidEnd || !HasCExtension.B)
210cf7d6b7aSMuzi    h_validEnd_halfPlus1(i) := h_validStart_halfPlus1(i) && currentIsRVC(i) || !h_validStart_halfPlus1(
211cf7d6b7aSMuzi      i
212cf7d6b7aSMuzi    ) || !HasCExtension.B
213330aad7fSGuokai Chen  }
214330aad7fSGuokai Chen  validStart_halfPlus1(PredictWidth / 2) := false.B // could be true but when true we select half, not halfPlus1
215330aad7fSGuokai Chen  validEnd_halfPlus1(PredictWidth / 2)   := true.B
216330aad7fSGuokai Chen
217330aad7fSGuokai Chen  // assume h_PredictWidth / 2 is an end
218330aad7fSGuokai Chen  h_validStart_halfPlus1(PredictWidth / 2) := false.B // could be true but when true we select half, not halfPlus1
219330aad7fSGuokai Chen  h_validEnd_halfPlus1(PredictWidth / 2)   := true.B
220330aad7fSGuokai Chen
221330aad7fSGuokai Chen  // if PredictWidth / 2 - 1 is a valid end, PredictWidth / 2 is a valid start
222330aad7fSGuokai Chen  for (i <- PredictWidth / 2 until PredictWidth) {
223330aad7fSGuokai Chen    validStart(i)   := Mux(validEnd(PredictWidth / 2 - 1), validStart_half(i), validStart_halfPlus1(i))
224330aad7fSGuokai Chen    validEnd(i)     := Mux(validEnd(PredictWidth / 2 - 1), validEnd_half(i), validEnd_halfPlus1(i))
225330aad7fSGuokai Chen    h_validStart(i) := Mux(h_validEnd(PredictWidth / 2 - 1), h_validStart_half(i), h_validStart_halfPlus1(i))
226330aad7fSGuokai Chen    h_validEnd(i)   := Mux(h_validEnd(PredictWidth / 2 - 1), h_validEnd_half(i), h_validEnd_halfPlus1(i))
227330aad7fSGuokai Chen  }
228330aad7fSGuokai Chen
229330aad7fSGuokai Chen  val validStartMismatch        = Wire(Bool())
230330aad7fSGuokai Chen  val validEndMismatch          = Wire(Bool())
231330aad7fSGuokai Chen  val validH_ValidStartMismatch = Wire(Bool())
232330aad7fSGuokai Chen  val validH_ValidEndMismatch   = Wire(Bool())
233330aad7fSGuokai Chen
234330aad7fSGuokai Chen  validStartMismatch        := validStart.zip(validStart_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
235330aad7fSGuokai Chen  validEndMismatch          := validEnd.zip(validEnd_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
236330aad7fSGuokai Chen  validH_ValidStartMismatch := h_validStart.zip(h_validStart_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
237330aad7fSGuokai Chen  validH_ValidEndMismatch   := h_validEnd.zip(h_validEnd_diff).map { case (a, b) => a =/= b }.reduce(_ || _)
238330aad7fSGuokai Chen
2399afa8a47STang Haojin  XSError(io.in.valid && validStartMismatch, p"validStart mismatch\n")
2409afa8a47STang Haojin  XSError(io.in.valid && validEndMismatch, p"validEnd mismatch\n")
2419afa8a47STang Haojin  XSError(io.in.valid && validH_ValidStartMismatch, p"h_validStart mismatch\n")
2429afa8a47STang Haojin  XSError(io.in.valid && validH_ValidEndMismatch, p"h_validEnd mismatch\n")
243330aad7fSGuokai Chen
244a4e57ea3SLi Qianruo//  io.out.hasLastHalf := !io.out.pd(PredictWidth - 1).isRVC && io.out.pd(PredictWidth - 1).valid
24509c6f1ddSLingrui98
24609c6f1ddSLingrui98  for (i <- 0 until PredictWidth) {
247cf7d6b7aSMuzi    XSDebug(
248cf7d6b7aSMuzi      true.B,
24948a62719SJenius      p"instr ${Hexadecimal(io.out.instr(i))}, " +
25009c6f1ddSLingrui98        p"validStart ${Binary(validStart(i))}, " +
25109c6f1ddSLingrui98        p"validEnd ${Binary(validEnd(i))}, " +
25209c6f1ddSLingrui98        p"isRVC ${Binary(io.out.pd(i).isRVC)}, " +
25309c6f1ddSLingrui98        p"brType ${Binary(io.out.pd(i).brType)}, " +
25409c6f1ddSLingrui98        p"isRet ${Binary(io.out.pd(i).isRet)}, " +
25509c6f1ddSLingrui98        p"isCall ${Binary(io.out.pd(i).isCall)}\n"
25609c6f1ddSLingrui98    )
25709c6f1ddSLingrui98  }
25809c6f1ddSLingrui98}
25909c6f1ddSLingrui98
260330aad7fSGuokai Chenclass IfuToF3PreDecode(implicit p: Parameters) extends XSBundle with HasPdConst {
261330aad7fSGuokai Chen  val instr = Vec(PredictWidth, UInt(32.W))
262330aad7fSGuokai Chen}
263330aad7fSGuokai Chen
264330aad7fSGuokai Chenclass F3PreDecodeResp(implicit p: Parameters) extends XSBundle with HasPdConst {
265330aad7fSGuokai Chen  val pd = Vec(PredictWidth, new PreDecodeInfo)
266330aad7fSGuokai Chen}
267330aad7fSGuokai Chenclass F3Predecoder(implicit p: Parameters) extends XSModule with HasPdConst {
268330aad7fSGuokai Chen  val io = IO(new Bundle() {
269330aad7fSGuokai Chen    val in  = Input(new IfuToF3PreDecode)
270330aad7fSGuokai Chen    val out = Output(new F3PreDecodeResp)
271330aad7fSGuokai Chen  })
272330aad7fSGuokai Chen  io.out.pd.zipWithIndex.map { case (pd, i) =>
273330aad7fSGuokai Chen    pd.valid  := DontCare
274330aad7fSGuokai Chen    pd.isRVC  := DontCare
275330aad7fSGuokai Chen    pd.brType := brInfo(io.in.instr(i))(0)
276330aad7fSGuokai Chen    pd.isCall := brInfo(io.in.instr(i))(1)
277330aad7fSGuokai Chen    pd.isRet  := brInfo(io.in.instr(i))(2)
278330aad7fSGuokai Chen  }
279330aad7fSGuokai Chen
280330aad7fSGuokai Chen}
281330aad7fSGuokai Chen
28209c6f1ddSLingrui98class RVCExpander(implicit p: Parameters) extends XSModule {
28309c6f1ddSLingrui98  val io = IO(new Bundle {
28409c6f1ddSLingrui98    val in      = Input(UInt(32.W))
28571b6c42eSxu_zh    val fsIsOff = Input(Bool())
28609c6f1ddSLingrui98    val out     = Output(new ExpandedInstruction)
287aeedc8eeSGuokai Chen    val ill     = Output(Bool())
28809c6f1ddSLingrui98  })
28909c6f1ddSLingrui98
29071b6c42eSxu_zh  val decoder = new RVCDecoder(io.in, io.fsIsOff, XLEN, fLen, useAddiForMv = true)
291aeedc8eeSGuokai Chen
29209c6f1ddSLingrui98  if (HasCExtension) {
293aeedc8eeSGuokai Chen    io.out := decoder.decode
294aeedc8eeSGuokai Chen    io.ill := decoder.ill
29509c6f1ddSLingrui98  } else {
296aeedc8eeSGuokai Chen    io.out := decoder.passthrough
297aeedc8eeSGuokai Chen    io.ill := false.B
29809c6f1ddSLingrui98  }
29909c6f1ddSLingrui98}
300a4e57ea3SLi Qianruo
301a4e57ea3SLi Qianruo/* ---------------------------------------------------------------------
302a4e57ea3SLi Qianruo * Predict result check
303a4e57ea3SLi Qianruo *
304a4e57ea3SLi Qianruo * ---------------------------------------------------------------------
305a4e57ea3SLi Qianruo */
306a4e57ea3SLi Qianruo
307a4e57ea3SLi Qianruoobject FaultType {
308a4e57ea3SLi Qianruo  def noFault      = "b000".U
309a4e57ea3SLi Qianruo  def jalFault     = "b001".U // not CFI taken or invalid instruction taken
310a4e57ea3SLi Qianruo  def retFault     = "b010".U // not CFI taken or invalid instruction taken
311a4e57ea3SLi Qianruo  def targetFault  = "b011".U
3125b3c20f7SJinYue  def notCFIFault  = "b100".U // not CFI taken or invalid instruction taken
3135b3c20f7SJinYue  def invalidTaken = "b101".U
314c670557fSHuSipeng  def jalrFault    = "b110".U
315a4e57ea3SLi Qianruo  def apply()      = UInt(3.W)
316a4e57ea3SLi Qianruo}
317a4e57ea3SLi Qianruo
318a4e57ea3SLi Qianruoclass CheckInfo extends Bundle { // 8 bit
319a4e57ea3SLi Qianruo  val value             = UInt(3.W)
320a4e57ea3SLi Qianruo  def isjalFault        = value === FaultType.jalFault
321c670557fSHuSipeng  def isjalrFault       = value === FaultType.jalrFault
322a4e57ea3SLi Qianruo  def isRetFault        = value === FaultType.retFault
323a4e57ea3SLi Qianruo  def istargetFault     = value === FaultType.targetFault
3245b3c20f7SJinYue  def invalidTakenFault = value === FaultType.invalidTaken
3255b3c20f7SJinYue  def notCFIFault       = value === FaultType.notCFIFault
326a4e57ea3SLi Qianruo}
327a4e57ea3SLi Qianruo
328a4e57ea3SLi Qianruoclass PredCheckerResp(implicit p: Parameters) extends XSBundle with HasPdConst {
3295995c9e7SJenius  // to Ibuffer write port  (stage 1)
3305995c9e7SJenius  val stage1Out = new Bundle {
331a4e57ea3SLi Qianruo    val fixedRange = Vec(PredictWidth, Bool())
332a4e57ea3SLi Qianruo    val fixedTaken = Vec(PredictWidth, Bool())
3335995c9e7SJenius  }
3345995c9e7SJenius  // to Ftq write back port (stage 2)
3355995c9e7SJenius  val stage2Out = new Bundle {
336a4e57ea3SLi Qianruo    val fixedTarget   = Vec(PredictWidth, UInt(VAddrBits.W))
337d10ddd67SGuokai Chen    val jalTarget     = Vec(PredictWidth, UInt(VAddrBits.W))
338a4e57ea3SLi Qianruo    val fixedMissPred = Vec(PredictWidth, Bool())
339a4e57ea3SLi Qianruo    val faultType     = Vec(PredictWidth, new CheckInfo)
340a4e57ea3SLi Qianruo  }
3415995c9e7SJenius}
342a4e57ea3SLi Qianruo
343a4e57ea3SLi Qianruoclass PredChecker(implicit p: Parameters) extends XSModule with HasPdConst {
344a4e57ea3SLi Qianruo  val io = IO(new Bundle {
345a4e57ea3SLi Qianruo    val in  = Input(new IfuToPredChecker)
346a4e57ea3SLi Qianruo    val out = Output(new PredCheckerResp)
347a4e57ea3SLi Qianruo  })
348a4e57ea3SLi Qianruo
349a4e57ea3SLi Qianruo  val (takenIdx, predTaken)    = (io.in.ftqOffset.bits, io.in.ftqOffset.valid)
350cf7d6b7aSMuzi  val predTarget               = io.in.target
351a4e57ea3SLi Qianruo  val (instrRange, instrValid) = (io.in.instrRange, io.in.instrValid)
352a4e57ea3SLi Qianruo  val (pds, pc, jumpOffset)    = (io.in.pds, io.in.pc, io.in.jumpOffset)
353a4e57ea3SLi Qianruo
354c670557fSHuSipeng  val jalFaultVec, jalrFaultVec, retFaultVec, targetFault, notCFITaken, invalidTaken = Wire(Vec(PredictWidth, Bool()))
355a4e57ea3SLi Qianruo
356a4e57ea3SLi Qianruo  /** remask fault may appear together with other faults, but other faults are exclusive
357a4e57ea3SLi Qianruo    * so other f ault mast use fixed mask to keep only one fault would be found and redirect to Ftq
358a4e57ea3SLi Qianruo    * we first detecct remask fault and then use fixedRange to do second check
359a4e57ea3SLi Qianruo    **/
360a4e57ea3SLi Qianruo
3615995c9e7SJenius  // Stage 1: detect remask fault
362a4e57ea3SLi Qianruo  /** first check: remask Fault */
363cf7d6b7aSMuzi  jalFaultVec := VecInit(pds.zipWithIndex.map { case (pd, i) =>
364cf7d6b7aSMuzi    pd.isJal && instrRange(i) && instrValid(i) && (takenIdx > i.U && predTaken || !predTaken)
365cf7d6b7aSMuzi  })
366c670557fSHuSipeng  jalrFaultVec := VecInit(pds.zipWithIndex.map { case (pd, i) =>
367c670557fSHuSipeng    pd.isJalr && !pd.isRet && instrRange(i) && instrValid(i) && (takenIdx > i.U && predTaken || !predTaken)
368c670557fSHuSipeng  })
369cf7d6b7aSMuzi  retFaultVec := VecInit(pds.zipWithIndex.map { case (pd, i) =>
370cf7d6b7aSMuzi    pd.isRet && instrRange(i) && instrValid(i) && (takenIdx > i.U && predTaken || !predTaken)
371cf7d6b7aSMuzi  })
372c670557fSHuSipeng  val remaskFault = VecInit((0 until PredictWidth).map(i => jalFaultVec(i) || jalrFaultVec(i) || retFaultVec(i)))
373a4e57ea3SLi Qianruo  val remaskIdx   = ParallelPriorityEncoder(remaskFault.asUInt)
374a4e57ea3SLi Qianruo  val needRemask  = ParallelOR(remaskFault)
375a4e57ea3SLi Qianruo  val fixedRange  = instrRange.asUInt & (Fill(PredictWidth, !needRemask) | Fill(PredictWidth, 1.U(1.W)) >> ~remaskIdx)
376a4e57ea3SLi Qianruo
3774d53e0efSzhou tao  require(
3784d53e0efSzhou tao    isPow2(PredictWidth),
3794d53e0efSzhou tao    "If PredictWidth does not satisfy the power of 2," +
3804d53e0efSzhou tao      "expression: Fill(PredictWidth, 1.U(1.W)) >> ~remaskIdx is not right !!"
3814d53e0efSzhou tao  )
3824d53e0efSzhou tao
383cf7d6b7aSMuzi  io.out.stage1Out.fixedRange := fixedRange.asTypeOf(Vec(PredictWidth, Bool()))
384a4e57ea3SLi Qianruo
385cf7d6b7aSMuzi  io.out.stage1Out.fixedTaken := VecInit(pds.zipWithIndex.map { case (pd, i) =>
386*7f475a24SHuSipeng    instrValid(i) && fixedRange(i) && (pd.isRet || pd.isJal || pd.isJalr || takenIdx === i.U && predTaken && !pd.notCFI)
387cf7d6b7aSMuzi  })
388a4e57ea3SLi Qianruo
389a4e57ea3SLi Qianruo  /** second check: faulse prediction fault and target fault */
390cf7d6b7aSMuzi  notCFITaken := VecInit(pds.zipWithIndex.map { case (pd, i) =>
391cf7d6b7aSMuzi    fixedRange(i) && instrValid(i) && i.U === takenIdx && pd.notCFI && predTaken
392cf7d6b7aSMuzi  })
393cf7d6b7aSMuzi  invalidTaken := VecInit(pds.zipWithIndex.map { case (pd, i) =>
394cf7d6b7aSMuzi    fixedRange(i) && !instrValid(i) && i.U === takenIdx && predTaken
395cf7d6b7aSMuzi  })
396a4e57ea3SLi Qianruo
397cf7d6b7aSMuzi  val jumpTargets = VecInit(pds.zipWithIndex.map { case (pd, i) =>
398cf7d6b7aSMuzi    (pc(i) + jumpOffset(i)).asTypeOf(UInt(VAddrBits.W))
399cf7d6b7aSMuzi  })
400a4e57ea3SLi Qianruo  val seqTargets = VecInit((0 until PredictWidth).map(i => pc(i) + Mux(pds(i).isRVC || !instrValid(i), 2.U, 4.U)))
401a4e57ea3SLi Qianruo
4025995c9e7SJenius  // Stage 2: detect target fault
4035995c9e7SJenius  /** target calculation: in the next stage  */
4040c70648eSEaston Man  val fixedRangeNext   = RegEnable(fixedRange, io.in.fire_in)
4050c70648eSEaston Man  val instrValidNext   = RegEnable(instrValid, io.in.fire_in)
4060c70648eSEaston Man  val takenIdxNext     = RegEnable(takenIdx, io.in.fire_in)
4070c70648eSEaston Man  val predTakenNext    = RegEnable(predTaken, io.in.fire_in)
4080c70648eSEaston Man  val predTargetNext   = RegEnable(predTarget, io.in.fire_in)
4090c70648eSEaston Man  val jumpTargetsNext  = RegEnable(jumpTargets, io.in.fire_in)
4100c70648eSEaston Man  val seqTargetsNext   = RegEnable(seqTargets, io.in.fire_in)
4110c70648eSEaston Man  val pdsNext          = RegEnable(pds, io.in.fire_in)
4120c70648eSEaston Man  val jalFaultVecNext  = RegEnable(jalFaultVec, io.in.fire_in)
413c670557fSHuSipeng  val jalrFaultVecNext = RegEnable(jalrFaultVec, io.in.fire_in)
4140c70648eSEaston Man  val retFaultVecNext  = RegEnable(retFaultVec, io.in.fire_in)
4150c70648eSEaston Man  val notCFITakenNext  = RegEnable(notCFITaken, io.in.fire_in)
4160c70648eSEaston Man  val invalidTakenNext = RegEnable(invalidTaken, io.in.fire_in)
417a4e57ea3SLi Qianruo
418cf7d6b7aSMuzi  targetFault := VecInit(pdsNext.zipWithIndex.map { case (pd, i) =>
419cf7d6b7aSMuzi    fixedRangeNext(i) && instrValidNext(
420cf7d6b7aSMuzi      i
421cf7d6b7aSMuzi    ) && (pd.isJal || pd.isBr) && takenIdxNext === i.U && predTakenNext && (predTargetNext =/= jumpTargetsNext(i))
422cf7d6b7aSMuzi  })
4235995c9e7SJenius
424cf7d6b7aSMuzi  io.out.stage2Out.faultType.zipWithIndex.foreach { case (faultType, i) =>
425c670557fSHuSipeng    faultType.value := MuxCase(
426c670557fSHuSipeng      FaultType.noFault,
427c670557fSHuSipeng      Seq(
428c670557fSHuSipeng        jalFaultVecNext(i)  -> FaultType.jalFault,
429c670557fSHuSipeng        jalrFaultVecNext(i) -> FaultType.jalrFault,
430c670557fSHuSipeng        retFaultVecNext(i)  -> FaultType.retFault,
431c670557fSHuSipeng        targetFault(i)      -> FaultType.targetFault,
432c670557fSHuSipeng        notCFITakenNext(i)  -> FaultType.notCFIFault,
433c670557fSHuSipeng        invalidTakenNext(i) -> FaultType.invalidTaken
434cf7d6b7aSMuzi      )
435cf7d6b7aSMuzi    )
436cf7d6b7aSMuzi  }
4375995c9e7SJenius
438cf7d6b7aSMuzi  io.out.stage2Out.fixedMissPred.zipWithIndex.foreach { case (missPred, i) =>
439c670557fSHuSipeng    missPred := jalFaultVecNext(i) || jalrFaultVecNext(i) || retFaultVecNext(i) || notCFITakenNext(i) ||
440c670557fSHuSipeng      invalidTakenNext(i) || targetFault(i)
441cf7d6b7aSMuzi  }
442cf7d6b7aSMuzi  io.out.stage2Out.fixedTarget.zipWithIndex.foreach { case (target, i) =>
443cf7d6b7aSMuzi    target := Mux(jalFaultVecNext(i) || targetFault(i), jumpTargetsNext(i), seqTargetsNext(i))
444cf7d6b7aSMuzi  }
4450c70648eSEaston Man  io.out.stage2Out.jalTarget.zipWithIndex.foreach { case (target, i) => target := jumpTargetsNext(i) }
446a4e57ea3SLi Qianruo
447a4e57ea3SLi Qianruo}
448a4e57ea3SLi Qianruo
449f7af4c74Schengguanghuiclass FrontendTrigger(implicit p: Parameters) extends XSModule with SdtrigExt {
450a4e57ea3SLi Qianruo  val io = IO(new Bundle() {
451a4e57ea3SLi Qianruo    val frontendTrigger = Input(new FrontendTdataDistributeIO)
4527e0f64b0SGuanghui Cheng    val triggered       = Output(Vec(PredictWidth, TriggerAction()))
453a4e57ea3SLi Qianruo
454a4e57ea3SLi Qianruo    val pds = Input(Vec(PredictWidth, new PreDecodeInfo))
455a4e57ea3SLi Qianruo    val pc  = Input(Vec(PredictWidth, UInt(VAddrBits.W)))
456a4e57ea3SLi Qianruo    val data = if (HasCExtension) Input(Vec(PredictWidth + 1, UInt(16.W)))
457a4e57ea3SLi Qianruo    else Input(Vec(PredictWidth, UInt(32.W)))
458a4e57ea3SLi Qianruo  })
459a4e57ea3SLi Qianruo
460a4e57ea3SLi Qianruo  val data = io.data
461a4e57ea3SLi Qianruo
462a4e57ea3SLi Qianruo  val rawInsts = if (HasCExtension) VecInit((0 until PredictWidth).map(i => Cat(data(i + 1), data(i))))
463a4e57ea3SLi Qianruo  else VecInit((0 until PredictWidth).map(i => data(i)))
464a4e57ea3SLi Qianruo
4657e0f64b0SGuanghui Cheng  val tdataVec = RegInit(VecInit(Seq.fill(TriggerNum)(0.U.asTypeOf(new MatchTriggerIO))))
466f7af4c74Schengguanghui  when(io.frontendTrigger.tUpdate.valid) {
4677e0f64b0SGuanghui Cheng    tdataVec(io.frontendTrigger.tUpdate.bits.addr) := io.frontendTrigger.tUpdate.bits.tdata
468a4e57ea3SLi Qianruo  }
469f7af4c74Schengguanghui  val triggerEnableVec = RegInit(VecInit(Seq.fill(TriggerNum)(false.B))) // From CSR, controlled by priv mode, etc.
470f7af4c74Schengguanghui  triggerEnableVec := io.frontendTrigger.tEnableVec
471f7af4c74Schengguanghui  XSDebug(triggerEnableVec.asUInt.orR, "Debug Mode: At least one frontend trigger is enabled\n")
472a4e57ea3SLi Qianruo
4737e0f64b0SGuanghui Cheng  val triggerTimingVec = VecInit(tdataVec.map(_.timing))
4747e0f64b0SGuanghui Cheng  val triggerChainVec  = VecInit(tdataVec.map(_.chain))
475f7af4c74Schengguanghui
4767e0f64b0SGuanghui Cheng  for (i <- 0 until TriggerNum) { PrintTriggerInfo(triggerEnableVec(i), tdataVec(i)) }
477a4e57ea3SLi Qianruo
4787e0f64b0SGuanghui Cheng  val debugMode            = io.frontendTrigger.debugMode
4797e0f64b0SGuanghui Cheng  val triggerCanRaiseBpExp = io.frontendTrigger.triggerCanRaiseBpExp
48047e7896cSchengguanghui  // val triggerHitVec = Wire(Vec(PredictWidth, Vec(TriggerNum, Bool())))
48147e7896cSchengguanghui  val triggerHitVec = (0 until TriggerNum).map(j =>
482cf7d6b7aSMuzi    TriggerCmpConsecutive(io.pc, tdataVec(j).tdata2, tdataVec(j).matchType, triggerEnableVec(j)).map(hit =>
483cf7d6b7aSMuzi      hit && !tdataVec(j).select && !debugMode
484cf7d6b7aSMuzi    )
48547e7896cSchengguanghui  ).transpose
48647e7896cSchengguanghui
487a4e57ea3SLi Qianruo  for (i <- 0 until PredictWidth) {
488f7af4c74Schengguanghui    val triggerCanFireVec = Wire(Vec(TriggerNum, Bool()))
48947e7896cSchengguanghui    TriggerCheckCanFire(TriggerNum, triggerCanFireVec, VecInit(triggerHitVec(i)), triggerTimingVec, triggerChainVec)
4907e0f64b0SGuanghui Cheng
4917e0f64b0SGuanghui Cheng    val actionVec     = VecInit(tdataVec.map(_.action))
4927e0f64b0SGuanghui Cheng    val triggerAction = Wire(TriggerAction())
4937e0f64b0SGuanghui Cheng    TriggerUtil.triggerActionGen(triggerAction, triggerCanFireVec, actionVec, triggerCanRaiseBpExp)
4947e0f64b0SGuanghui Cheng
4957e0f64b0SGuanghui Cheng    // Priority may select last when no trigger fire.
4967e0f64b0SGuanghui Cheng    io.triggered(i) := triggerAction
497cf7d6b7aSMuzi    XSDebug(
498cf7d6b7aSMuzi      triggerCanFireVec.asUInt.orR,
499cf7d6b7aSMuzi      p"Debug Mode: Predecode Inst No. ${i} has trigger action vec ${triggerCanFireVec.asUInt.orR}\n"
500cf7d6b7aSMuzi    )
501a4e57ea3SLi Qianruo  }
502a4e57ea3SLi Qianruo}
503