xref: /XiangShan/src/main/scala/xiangshan/backend/rob/Rob.scala (revision d8aa3d57ee3367828b7a51544c0d78d331d3c295)
1/***************************************************************************************
2* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
3* Copyright (c) 2020-2021 Peng Cheng Laboratory
4*
5* XiangShan is licensed under Mulan PSL v2.
6* You can use this software according to the terms and conditions of the Mulan PSL v2.
7* You may obtain a copy of Mulan PSL v2 at:
8*          http://license.coscl.org.cn/MulanPSL2
9*
10* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
11* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
12* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
13*
14* See the Mulan PSL v2 for more details.
15***************************************************************************************/
16
17package xiangshan.backend.rob
18
19import chipsalliance.rocketchip.config.Parameters
20import chisel3._
21import chisel3.util._
22import difftest._
23import freechips.rocketchip.diplomacy.{LazyModule, LazyModuleImp}
24import utils._
25import utility._
26import xiangshan._
27import xiangshan.backend.exu.ExuConfig
28import xiangshan.frontend.FtqPtr
29
30class DebugMdpInfo(implicit p: Parameters) extends XSBundle{
31  val ssid = UInt(SSIDWidth.W)
32  val waitAllStore = Bool()
33}
34
35class DebugLsInfo(implicit p: Parameters) extends XSBundle{
36  val s1 = new Bundle{
37    val isTlbFirstMiss = Bool() // in s1
38    val isBankConflict = Bool() // in s1
39    val isLoadToLoadForward = Bool()
40    val isReplayFast = Bool()
41  }
42  val s2 = new Bundle{
43    val isDcacheFirstMiss = Bool() // in s2 (predicted result is in s1 when using WPU, real result is in s2)
44    val isForwardFail = Bool() // in s2
45    val isReplaySlow = Bool()
46    val isLoadReplayTLBMiss = Bool()
47    val isLoadReplayCacheMiss = Bool()
48  }
49  val replayCnt = UInt(XLEN.W)
50
51  def s1SignalEnable(ena: DebugLsInfo) = {
52    when(ena.s1.isTlbFirstMiss) { s1.isTlbFirstMiss := true.B }
53    when(ena.s1.isBankConflict) { s1.isBankConflict := true.B }
54    when(ena.s1.isLoadToLoadForward) { s1.isLoadToLoadForward := true.B }
55    when(ena.s1.isReplayFast) {
56      s1.isReplayFast := true.B
57      replayCnt := replayCnt + 1.U
58    }
59  }
60
61  def s2SignalEnable(ena: DebugLsInfo) = {
62    when(ena.s2.isDcacheFirstMiss) { s2.isDcacheFirstMiss := true.B }
63    when(ena.s2.isForwardFail) { s2.isForwardFail := true.B }
64    when(ena.s2.isLoadReplayTLBMiss) { s2.isLoadReplayTLBMiss := true.B }
65    when(ena.s2.isLoadReplayCacheMiss) { s2.isLoadReplayCacheMiss := true.B }
66    when(ena.s2.isReplaySlow) {
67      s2.isReplaySlow := true.B
68      replayCnt := replayCnt + 1.U
69    }
70  }
71
72}
73object DebugLsInfo{
74  def init(implicit p: Parameters): DebugLsInfo = {
75    val lsInfo = Wire(new DebugLsInfo)
76    lsInfo.s1.isTlbFirstMiss := false.B
77    lsInfo.s1.isBankConflict := false.B
78    lsInfo.s1.isLoadToLoadForward := false.B
79    lsInfo.s1.isReplayFast := false.B
80    lsInfo.s2.isDcacheFirstMiss := false.B
81    lsInfo.s2.isForwardFail := false.B
82    lsInfo.s2.isReplaySlow := false.B
83    lsInfo.s2.isLoadReplayTLBMiss := false.B
84    lsInfo.s2.isLoadReplayCacheMiss := false.B
85    lsInfo.replayCnt := 0.U
86    lsInfo
87  }
88
89}
90class DebugLsInfoBundle(implicit p: Parameters) extends DebugLsInfo {
91  // unified processing at the end stage of load/store  ==> s2  ==> bug that will write error robIdx data
92  val s1_robIdx = UInt(log2Ceil(RobSize).W)
93  val s2_robIdx = UInt(log2Ceil(RobSize).W)
94}
95class DebugLSIO(implicit p: Parameters) extends XSBundle {
96  val debugLsInfo = Vec(exuParameters.LduCnt + exuParameters.StuCnt, Output(new DebugLsInfoBundle))
97}
98
99class RobPtr(implicit p: Parameters) extends CircularQueuePtr[RobPtr](
100  p => p(XSCoreParamsKey).RobSize
101) with HasCircularQueuePtrHelper {
102
103  def needFlush(redirect: Valid[Redirect]): Bool = {
104    val flushItself = redirect.bits.flushItself() && this === redirect.bits.robIdx
105    redirect.valid && (flushItself || isAfter(this, redirect.bits.robIdx))
106  }
107
108  def needFlush(redirect: Seq[Valid[Redirect]]): Bool = VecInit(redirect.map(needFlush)).asUInt.orR
109}
110
111object RobPtr {
112  def apply(f: Bool, v: UInt)(implicit p: Parameters): RobPtr = {
113    val ptr = Wire(new RobPtr)
114    ptr.flag := f
115    ptr.value := v
116    ptr
117  }
118}
119
120class RobCSRIO(implicit p: Parameters) extends XSBundle {
121  val intrBitSet = Input(Bool())
122  val trapTarget = Input(UInt(VAddrBits.W))
123  val isXRet     = Input(Bool())
124  val wfiEvent   = Input(Bool())
125
126  val fflags     = Output(Valid(UInt(5.W)))
127  val dirty_fs   = Output(Bool())
128  val perfinfo   = new Bundle {
129    val retiredInstr = Output(UInt(3.W))
130  }
131}
132
133class RobLsqIO(implicit p: Parameters) extends XSBundle {
134  val lcommit = Output(UInt(log2Up(CommitWidth + 1).W))
135  val scommit = Output(UInt(log2Up(CommitWidth + 1).W))
136  val pendingld = Output(Bool())
137  val pendingst = Output(Bool())
138  val commit = Output(Bool())
139}
140
141class RobEnqIO(implicit p: Parameters) extends XSBundle {
142  val canAccept = Output(Bool())
143  val isEmpty = Output(Bool())
144  // valid vector, for robIdx gen and walk
145  val needAlloc = Vec(RenameWidth, Input(Bool()))
146  val req = Vec(RenameWidth, Flipped(ValidIO(new MicroOp)))
147  val resp = Vec(RenameWidth, Output(new RobPtr))
148}
149
150class RobDispatchData(implicit p: Parameters) extends RobCommitInfo
151
152class RobDeqPtrWrapper(implicit p: Parameters) extends XSModule with HasCircularQueuePtrHelper {
153  val io = IO(new Bundle {
154    // for commits/flush
155    val state = Input(UInt(2.W))
156    val deq_v = Vec(CommitWidth, Input(Bool()))
157    val deq_w = Vec(CommitWidth, Input(Bool()))
158    val exception_state = Flipped(ValidIO(new RobExceptionInfo))
159    // for flush: when exception occurs, reset deqPtrs to range(0, CommitWidth)
160    val intrBitSetReg = Input(Bool())
161    val hasNoSpecExec = Input(Bool())
162    val interrupt_safe = Input(Bool())
163    val blockCommit = Input(Bool())
164    // output: the CommitWidth deqPtr
165    val out = Vec(CommitWidth, Output(new RobPtr))
166    val next_out = Vec(CommitWidth, Output(new RobPtr))
167  })
168
169  val deqPtrVec = RegInit(VecInit((0 until CommitWidth).map(_.U.asTypeOf(new RobPtr))))
170
171  // for exceptions (flushPipe included) and interrupts:
172  // only consider the first instruction
173  val intrEnable = io.intrBitSetReg && !io.hasNoSpecExec && io.interrupt_safe
174  val exceptionEnable = io.deq_w(0) && io.exception_state.valid && io.exception_state.bits.not_commit && io.exception_state.bits.robIdx === deqPtrVec(0)
175  val redirectOutValid = io.state === 0.U && io.deq_v(0) && (intrEnable || exceptionEnable)
176
177  // for normal commits: only to consider when there're no exceptions
178  // we don't need to consider whether the first instruction has exceptions since it wil trigger exceptions.
179  val commit_exception = io.exception_state.valid && !isAfter(io.exception_state.bits.robIdx, deqPtrVec.last)
180  val canCommit = VecInit((0 until CommitWidth).map(i => io.deq_v(i) && io.deq_w(i)))
181  val normalCommitCnt = PriorityEncoder(canCommit.map(c => !c) :+ true.B)
182  // when io.intrBitSetReg or there're possible exceptions in these instructions,
183  // only one instruction is allowed to commit
184  val allowOnlyOne = commit_exception || io.intrBitSetReg
185  val commitCnt = Mux(allowOnlyOne, canCommit(0), normalCommitCnt)
186
187  val commitDeqPtrVec = VecInit(deqPtrVec.map(_ + commitCnt))
188  val deqPtrVec_next = Mux(io.state === 0.U && !redirectOutValid && !io.blockCommit, commitDeqPtrVec, deqPtrVec)
189
190  deqPtrVec := deqPtrVec_next
191
192  io.next_out := deqPtrVec_next
193  io.out      := deqPtrVec
194
195  when (io.state === 0.U) {
196    XSInfo(io.state === 0.U && commitCnt > 0.U, "retired %d insts\n", commitCnt)
197  }
198
199}
200
201class RobEnqPtrWrapper(implicit p: Parameters) extends XSModule with HasCircularQueuePtrHelper {
202  val io = IO(new Bundle {
203    // for input redirect
204    val redirect = Input(Valid(new Redirect))
205    // for enqueue
206    val allowEnqueue = Input(Bool())
207    val hasBlockBackward = Input(Bool())
208    val enq = Vec(RenameWidth, Input(Bool()))
209    val out = Output(Vec(RenameWidth, new RobPtr))
210  })
211
212  val enqPtrVec = RegInit(VecInit.tabulate(RenameWidth)(_.U.asTypeOf(new RobPtr)))
213
214  // enqueue
215  val canAccept = io.allowEnqueue && !io.hasBlockBackward
216  val dispatchNum = Mux(canAccept, PopCount(io.enq), 0.U)
217
218  for ((ptr, i) <- enqPtrVec.zipWithIndex) {
219    when(io.redirect.valid) {
220      ptr := Mux(io.redirect.bits.flushItself(), io.redirect.bits.robIdx + i.U, io.redirect.bits.robIdx + (i + 1).U)
221    }.otherwise {
222      ptr := ptr + dispatchNum
223    }
224  }
225
226  io.out := enqPtrVec
227
228}
229
230class RobExceptionInfo(implicit p: Parameters) extends XSBundle {
231  // val valid = Bool()
232  val robIdx = new RobPtr
233  val exceptionVec = ExceptionVec()
234  val flushPipe = Bool()
235  val replayInst = Bool() // redirect to that inst itself
236  val singleStep = Bool() // TODO add frontend hit beneath
237  val crossPageIPFFix = Bool()
238  val trigger = new TriggerCf
239
240//  def trigger_before = !trigger.getTimingBackend && trigger.getHitBackend
241//  def trigger_after = trigger.getTimingBackend && trigger.getHitBackend
242  def has_exception = exceptionVec.asUInt.orR || flushPipe || singleStep || replayInst || trigger.hit
243  def not_commit = exceptionVec.asUInt.orR || singleStep || replayInst || trigger.hit
244  // only exceptions are allowed to writeback when enqueue
245  def can_writeback = exceptionVec.asUInt.orR || singleStep || trigger.hit
246}
247
248class ExceptionGen(implicit p: Parameters) extends XSModule with HasCircularQueuePtrHelper {
249  val io = IO(new Bundle {
250    val redirect = Input(Valid(new Redirect))
251    val flush = Input(Bool())
252    val enq = Vec(RenameWidth, Flipped(ValidIO(new RobExceptionInfo)))
253    val wb = Vec(1 + LoadPipelineWidth + StorePipelineWidth, Flipped(ValidIO(new RobExceptionInfo)))
254    val out = ValidIO(new RobExceptionInfo)
255    val state = ValidIO(new RobExceptionInfo)
256  })
257
258  def getOldest(valid: Seq[Bool], bits: Seq[RobExceptionInfo]): (Seq[Bool], Seq[RobExceptionInfo]) = {
259    assert(valid.length == bits.length)
260    assert(isPow2(valid.length))
261    if (valid.length == 1) {
262      (valid, bits)
263    } else if (valid.length == 2) {
264      val res = Seq.fill(2)(Wire(ValidIO(chiselTypeOf(bits(0)))))
265      for (i <- res.indices) {
266        res(i).valid := valid(i)
267        res(i).bits := bits(i)
268      }
269      val oldest = Mux(!valid(1) || valid(0) && isAfter(bits(1).robIdx, bits(0).robIdx), res(0), res(1))
270      (Seq(oldest.valid), Seq(oldest.bits))
271    } else {
272      val left = getOldest(valid.take(valid.length / 2), bits.take(valid.length / 2))
273      val right = getOldest(valid.takeRight(valid.length / 2), bits.takeRight(valid.length / 2))
274      getOldest(left._1 ++ right._1, left._2 ++ right._2)
275    }
276  }
277
278  val currentValid = RegInit(false.B)
279  val current = Reg(new RobExceptionInfo)
280
281  // orR the exceptionVec
282  val lastCycleFlush = RegNext(io.flush)
283  val in_enq_valid = VecInit(io.enq.map(e => e.valid && e.bits.has_exception && !lastCycleFlush))
284  val in_wb_valid = io.wb.map(w => w.valid && w.bits.has_exception && !lastCycleFlush)
285
286  // s0: compare wb(1)~wb(LoadPipelineWidth) and wb(1 + LoadPipelineWidth)~wb(LoadPipelineWidth + StorePipelineWidth)
287  val wb_valid = in_wb_valid.zip(io.wb.map(_.bits)).map{ case (v, bits) => v && !(bits.robIdx.needFlush(io.redirect) || io.flush) }
288  val csr_wb_bits = io.wb(0).bits
289  val load_wb_bits = getOldest(in_wb_valid.slice(1, 1 + LoadPipelineWidth), io.wb.map(_.bits).slice(1, 1 + LoadPipelineWidth))._2(0)
290  val store_wb_bits = getOldest(in_wb_valid.slice(1 + LoadPipelineWidth, 1 + LoadPipelineWidth + StorePipelineWidth), io.wb.map(_.bits).slice(1 + LoadPipelineWidth, 1 + LoadPipelineWidth + StorePipelineWidth))._2(0)
291  val s0_out_valid = RegNext(VecInit(Seq(wb_valid(0), wb_valid.slice(1, 1 + LoadPipelineWidth).reduce(_ || _), wb_valid.slice(1 + LoadPipelineWidth, 1 + LoadPipelineWidth + StorePipelineWidth).reduce(_ || _))))
292  val s0_out_bits = RegNext(VecInit(Seq(csr_wb_bits, load_wb_bits, store_wb_bits)))
293
294  // s1: compare last four and current flush
295  val s1_valid = VecInit(s0_out_valid.zip(s0_out_bits).map{ case (v, b) => v && !(b.robIdx.needFlush(io.redirect) || io.flush) })
296  val compare_01_valid = s0_out_valid(0) || s0_out_valid(1)
297  val compare_01_bits = Mux(!s0_out_valid(0) || s0_out_valid(1) && isAfter(s0_out_bits(0).robIdx, s0_out_bits(1).robIdx), s0_out_bits(1), s0_out_bits(0))
298  val compare_bits = Mux(!s0_out_valid(2) || compare_01_valid && isAfter(s0_out_bits(2).robIdx, compare_01_bits.robIdx), compare_01_bits, s0_out_bits(2))
299  val s1_out_bits = RegNext(compare_bits)
300  val s1_out_valid = RegNext(s1_valid.asUInt.orR)
301
302  val enq_valid = RegNext(in_enq_valid.asUInt.orR && !io.redirect.valid && !io.flush)
303  val enq_bits = RegNext(ParallelPriorityMux(in_enq_valid, io.enq.map(_.bits)))
304
305  // s2: compare the input exception with the current one
306  // priorities:
307  // (1) system reset
308  // (2) current is valid: flush, remain, merge, update
309  // (3) current is not valid: s1 or enq
310  val current_flush = current.robIdx.needFlush(io.redirect) || io.flush
311  val s1_flush = s1_out_bits.robIdx.needFlush(io.redirect) || io.flush
312  when (currentValid) {
313    when (current_flush) {
314      currentValid := Mux(s1_flush, false.B, s1_out_valid)
315    }
316    when (s1_out_valid && !s1_flush) {
317      when (isAfter(current.robIdx, s1_out_bits.robIdx)) {
318        current := s1_out_bits
319      }.elsewhen (current.robIdx === s1_out_bits.robIdx) {
320        current.exceptionVec := (s1_out_bits.exceptionVec.asUInt | current.exceptionVec.asUInt).asTypeOf(ExceptionVec())
321        current.flushPipe := s1_out_bits.flushPipe || current.flushPipe
322        current.replayInst := s1_out_bits.replayInst || current.replayInst
323        current.singleStep := s1_out_bits.singleStep || current.singleStep
324        current.trigger := (s1_out_bits.trigger.asUInt | current.trigger.asUInt).asTypeOf(new TriggerCf)
325      }
326    }
327  }.elsewhen (s1_out_valid && !s1_flush) {
328    currentValid := true.B
329    current := s1_out_bits
330  }.elsewhen (enq_valid && !(io.redirect.valid || io.flush)) {
331    currentValid := true.B
332    current := enq_bits
333  }
334
335  io.out.valid   := s1_out_valid || enq_valid && enq_bits.can_writeback
336  io.out.bits    := Mux(s1_out_valid, s1_out_bits, enq_bits)
337  io.state.valid := currentValid
338  io.state.bits  := current
339
340}
341
342class RobFlushInfo(implicit p: Parameters) extends XSBundle {
343  val ftqIdx = new FtqPtr
344  val robIdx = new RobPtr
345  val ftqOffset = UInt(log2Up(PredictWidth).W)
346  val replayInst = Bool()
347}
348
349class Rob(implicit p: Parameters) extends LazyModule with HasWritebackSink with HasXSParameter {
350
351  lazy val module = new RobImp(this)
352
353  override def generateWritebackIO(
354    thisMod: Option[HasWritebackSource] = None,
355    thisModImp: Option[HasWritebackSourceImp] = None
356  ): Unit = {
357    val sources = writebackSinksImp(thisMod, thisModImp)
358    module.io.writeback.zip(sources).foreach(x => x._1 := x._2)
359  }
360}
361
362class RobImp(outer: Rob)(implicit p: Parameters) extends LazyModuleImp(outer)
363  with HasXSParameter with HasCircularQueuePtrHelper with HasPerfEvents {
364  val wbExuConfigs = outer.writebackSinksParams.map(_.exuConfigs)
365  val numWbPorts = wbExuConfigs.map(_.length)
366
367  val io = IO(new Bundle() {
368    val hartId = Input(UInt(8.W))
369    val redirect = Input(Valid(new Redirect))
370    val enq = new RobEnqIO
371    val flushOut = ValidIO(new Redirect)
372    val exception = ValidIO(new ExceptionInfo)
373    // exu + brq
374    val writeback = MixedVec(numWbPorts.map(num => Vec(num, Flipped(ValidIO(new ExuOutput)))))
375    val commits = Output(new RobCommitIO)
376    val lsq = new RobLsqIO
377    val robDeqPtr = Output(new RobPtr)
378    val csr = new RobCSRIO
379    val robFull = Output(Bool())
380    val cpu_halt = Output(Bool())
381    val wfi_enable = Input(Bool())
382    val debug_ls = Flipped(new DebugLSIO)
383  })
384
385  def selectWb(index: Int, func: Seq[ExuConfig] => Boolean): Seq[(Seq[ExuConfig], ValidIO[ExuOutput])] = {
386    wbExuConfigs(index).zip(io.writeback(index)).filter(x => func(x._1))
387  }
388  val exeWbSel = outer.selWritebackSinks(_.exuConfigs.length)
389  val fflagsWbSel = outer.selWritebackSinks(_.exuConfigs.count(_.exists(_.writeFflags)))
390  val fflagsPorts = selectWb(fflagsWbSel, _.exists(_.writeFflags))
391  val exceptionWbSel = outer.selWritebackSinks(_.exuConfigs.count(_.exists(_.needExceptionGen)))
392  val exceptionPorts = selectWb(fflagsWbSel, _.exists(_.needExceptionGen))
393  val exuWbPorts = selectWb(exeWbSel, _.forall(_ != StdExeUnitCfg))
394  val stdWbPorts = selectWb(exeWbSel, _.contains(StdExeUnitCfg))
395  println(s"Rob: size $RobSize, numWbPorts: $numWbPorts, commitwidth: $CommitWidth")
396  println(s"exuPorts: ${exuWbPorts.map(_._1.map(_.name))}")
397  println(s"stdPorts: ${stdWbPorts.map(_._1.map(_.name))}")
398  println(s"fflags: ${fflagsPorts.map(_._1.map(_.name))}")
399
400
401  val exuWriteback = exuWbPorts.map(_._2)
402  val stdWriteback = stdWbPorts.map(_._2)
403
404  // instvalid field
405  val valid = RegInit(VecInit(Seq.fill(RobSize)(false.B)))
406  // writeback status
407  val writebacked = Mem(RobSize, Bool())
408  val store_data_writebacked = Mem(RobSize, Bool())
409  // data for redirect, exception, etc.
410  val flagBkup = Mem(RobSize, Bool())
411  // some instructions are not allowed to trigger interrupts
412  // They have side effects on the states of the processor before they write back
413  val interrupt_safe = Mem(RobSize, Bool())
414
415  // data for debug
416  // Warn: debug_* prefix should not exist in generated verilog.
417  val debug_microOp = Reg(Vec(RobSize, new MicroOp))
418  val debug_exuData = Reg(Vec(RobSize, UInt(XLEN.W)))//for debug
419  val debug_exuDebug = Reg(Vec(RobSize, new DebugBundle))//for debug
420  val debug_lsInfo = RegInit(VecInit(Seq.fill(RobSize)(DebugLsInfo.init)))
421
422  // pointers
423  // For enqueue ptr, we don't duplicate it since only enqueue needs it.
424  val enqPtrVec = Wire(Vec(RenameWidth, new RobPtr))
425  val deqPtrVec = Wire(Vec(CommitWidth, new RobPtr))
426
427  val walkPtrVec = Reg(Vec(CommitWidth, new RobPtr))
428  val allowEnqueue = RegInit(true.B)
429
430  val enqPtr = enqPtrVec.head
431  val deqPtr = deqPtrVec(0)
432  val walkPtr = walkPtrVec(0)
433
434  val isEmpty = enqPtr === deqPtr
435  val isReplaying = io.redirect.valid && RedirectLevel.flushItself(io.redirect.bits.level)
436
437  /**
438    * states of Rob
439    */
440  val s_idle :: s_walk :: Nil = Enum(2)
441  val state = RegInit(s_idle)
442
443  /**
444    * Data Modules
445    *
446    * CommitDataModule: data from dispatch
447    * (1) read: commits/walk/exception
448    * (2) write: enqueue
449    *
450    * WritebackData: data from writeback
451    * (1) read: commits/walk/exception
452    * (2) write: write back from exe units
453    */
454  val dispatchData = Module(new SyncDataModuleTemplate(new RobDispatchData, RobSize, CommitWidth, RenameWidth))
455  val dispatchDataRead = dispatchData.io.rdata
456
457  val exceptionGen = Module(new ExceptionGen)
458  val exceptionDataRead = exceptionGen.io.state
459  val fflagsDataRead = Wire(Vec(CommitWidth, UInt(5.W)))
460
461  io.robDeqPtr := deqPtr
462
463  /**
464    * Enqueue (from dispatch)
465    */
466  // special cases
467  val hasBlockBackward = RegInit(false.B)
468  val hasNoSpecExec = RegInit(false.B)
469  val doingSvinval = RegInit(false.B)
470  // When blockBackward instruction leaves Rob (commit or walk), hasBlockBackward should be set to false.B
471  // To reduce registers usage, for hasBlockBackward cases, we allow enqueue after ROB is empty.
472  when (isEmpty) { hasBlockBackward:= false.B }
473  // When any instruction commits, hasNoSpecExec should be set to false.B
474  when (io.commits.hasWalkInstr || io.commits.hasCommitInstr) { hasNoSpecExec:= false.B }
475
476  // The wait-for-interrupt (WFI) instruction waits in the ROB until an interrupt might need servicing.
477  // io.csr.wfiEvent will be asserted if the WFI can resume execution, and we change the state to s_wfi_idle.
478  // It does not affect how interrupts are serviced. Note that WFI is noSpecExec and it does not trigger interrupts.
479  val hasWFI = RegInit(false.B)
480  io.cpu_halt := hasWFI
481  // WFI Timeout: 2^20 = 1M cycles
482  val wfi_cycles = RegInit(0.U(20.W))
483  when (hasWFI) {
484    wfi_cycles := wfi_cycles + 1.U
485  }.elsewhen (!hasWFI && RegNext(hasWFI)) {
486    wfi_cycles := 0.U
487  }
488  val wfi_timeout = wfi_cycles.andR
489  when (RegNext(RegNext(io.csr.wfiEvent)) || io.flushOut.valid || wfi_timeout) {
490    hasWFI := false.B
491  }
492
493  val allocatePtrVec = VecInit((0 until RenameWidth).map(i => enqPtrVec(PopCount(io.enq.needAlloc.take(i)))))
494  io.enq.canAccept := allowEnqueue && !hasBlockBackward
495  io.enq.resp      := allocatePtrVec
496  val canEnqueue = VecInit(io.enq.req.map(_.valid && io.enq.canAccept))
497  val timer = GTimer()
498  for (i <- 0 until RenameWidth) {
499    // we don't check whether io.redirect is valid here since redirect has higher priority
500    when (canEnqueue(i)) {
501      val enqUop = io.enq.req(i).bits
502      val enqIndex = allocatePtrVec(i).value
503      // store uop in data module and debug_microOp Vec
504      debug_microOp(enqIndex) := enqUop
505      debug_microOp(enqIndex).debugInfo.dispatchTime := timer
506      debug_microOp(enqIndex).debugInfo.enqRsTime := timer
507      debug_microOp(enqIndex).debugInfo.selectTime := timer
508      debug_microOp(enqIndex).debugInfo.issueTime := timer
509      debug_microOp(enqIndex).debugInfo.writebackTime := timer
510      debug_microOp(enqIndex).debugInfo.tlbFirstReqTime := timer
511      debug_microOp(enqIndex).debugInfo.tlbRespTime := timer
512      debug_lsInfo(enqIndex) := DebugLsInfo.init
513      when (enqUop.ctrl.blockBackward) {
514        hasBlockBackward := true.B
515      }
516      when (enqUop.ctrl.noSpecExec) {
517        hasNoSpecExec := true.B
518      }
519      val enqHasTriggerHit = io.enq.req(i).bits.cf.trigger.getHitFrontend
520      val enqHasException = ExceptionNO.selectFrontend(enqUop.cf.exceptionVec).asUInt.orR
521      // the begin instruction of Svinval enqs so mark doingSvinval as true to indicate this process
522      when(!enqHasTriggerHit && !enqHasException && FuType.isSvinvalBegin(enqUop.ctrl.fuType, enqUop.ctrl.fuOpType, enqUop.ctrl.flushPipe))
523      {
524        doingSvinval := true.B
525      }
526      // the end instruction of Svinval enqs so clear doingSvinval
527      when(!enqHasTriggerHit && !enqHasException && FuType.isSvinvalEnd(enqUop.ctrl.fuType, enqUop.ctrl.fuOpType, enqUop.ctrl.flushPipe))
528      {
529        doingSvinval := false.B
530      }
531      // when we are in the process of Svinval software code area , only Svinval.vma and end instruction of Svinval can appear
532      assert(!doingSvinval || (FuType.isSvinval(enqUop.ctrl.fuType, enqUop.ctrl.fuOpType, enqUop.ctrl.flushPipe) ||
533        FuType.isSvinvalEnd(enqUop.ctrl.fuType, enqUop.ctrl.fuOpType, enqUop.ctrl.flushPipe)))
534      when (enqUop.ctrl.isWFI && !enqHasException && !enqHasTriggerHit) {
535        hasWFI := true.B
536      }
537    }
538  }
539  val dispatchNum = Mux(io.enq.canAccept, PopCount(io.enq.req.map(_.valid)), 0.U)
540  io.enq.isEmpty   := RegNext(isEmpty && !VecInit(io.enq.req.map(_.valid)).asUInt.orR)
541
542  when (!io.wfi_enable) {
543    hasWFI := false.B
544  }
545
546  /**
547    * Writeback (from execution units)
548    */
549  for (wb <- exuWriteback) {
550    when (wb.valid) {
551      val wbIdx = wb.bits.uop.robIdx.value
552      debug_exuData(wbIdx) := wb.bits.data
553      debug_exuDebug(wbIdx) := wb.bits.debug
554      debug_microOp(wbIdx).debugInfo.enqRsTime := wb.bits.uop.debugInfo.enqRsTime
555      debug_microOp(wbIdx).debugInfo.selectTime := wb.bits.uop.debugInfo.selectTime
556      debug_microOp(wbIdx).debugInfo.issueTime := wb.bits.uop.debugInfo.issueTime
557      debug_microOp(wbIdx).debugInfo.writebackTime := wb.bits.uop.debugInfo.writebackTime
558      debug_microOp(wbIdx).debugInfo.tlbFirstReqTime := wb.bits.uop.debugInfo.tlbFirstReqTime
559      debug_microOp(wbIdx).debugInfo.tlbRespTime := wb.bits.uop.debugInfo.tlbRespTime
560
561      // debug for lqidx and sqidx
562      debug_microOp(wbIdx).lqIdx := wb.bits.uop.lqIdx
563      debug_microOp(wbIdx).sqIdx := wb.bits.uop.sqIdx
564
565      val debug_Uop = debug_microOp(wbIdx)
566      XSInfo(true.B,
567        p"writebacked pc 0x${Hexadecimal(debug_Uop.cf.pc)} wen ${debug_Uop.ctrl.rfWen} " +
568        p"data 0x${Hexadecimal(wb.bits.data)} ldst ${debug_Uop.ctrl.ldest} pdst ${debug_Uop.pdest} " +
569        p"skip ${wb.bits.debug.isMMIO} robIdx: ${wb.bits.uop.robIdx}\n"
570      )
571    }
572  }
573  val writebackNum = PopCount(exuWriteback.map(_.valid))
574  XSInfo(writebackNum =/= 0.U, "writebacked %d insts\n", writebackNum)
575
576
577  /**
578    * RedirectOut: Interrupt and Exceptions
579    */
580  val deqDispatchData = dispatchDataRead(0)
581  val debug_deqUop = debug_microOp(deqPtr.value)
582
583  val intrBitSetReg = RegNext(io.csr.intrBitSet)
584  val intrEnable = intrBitSetReg && !hasNoSpecExec && interrupt_safe(deqPtr.value)
585  val deqHasExceptionOrFlush = exceptionDataRead.valid && exceptionDataRead.bits.robIdx === deqPtr
586  val deqHasException = deqHasExceptionOrFlush && (exceptionDataRead.bits.exceptionVec.asUInt.orR ||
587    exceptionDataRead.bits.singleStep || exceptionDataRead.bits.trigger.hit)
588  val deqHasFlushPipe = deqHasExceptionOrFlush && exceptionDataRead.bits.flushPipe
589  val deqHasReplayInst = deqHasExceptionOrFlush && exceptionDataRead.bits.replayInst
590  val exceptionEnable = writebacked(deqPtr.value) && deqHasException
591
592  XSDebug(deqHasException && exceptionDataRead.bits.singleStep, "Debug Mode: Deq has singlestep exception\n")
593  XSDebug(deqHasException && exceptionDataRead.bits.trigger.getHitFrontend, "Debug Mode: Deq has frontend trigger exception\n")
594  XSDebug(deqHasException && exceptionDataRead.bits.trigger.getHitBackend, "Debug Mode: Deq has backend trigger exception\n")
595
596  val isFlushPipe = writebacked(deqPtr.value) && (deqHasFlushPipe || deqHasReplayInst)
597
598  // io.flushOut will trigger redirect at the next cycle.
599  // Block any redirect or commit at the next cycle.
600  val lastCycleFlush = RegNext(io.flushOut.valid)
601
602  io.flushOut.valid := (state === s_idle) && valid(deqPtr.value) && (intrEnable || exceptionEnable || isFlushPipe) && !lastCycleFlush
603  io.flushOut.bits := DontCare
604  io.flushOut.bits.robIdx := deqPtr
605  io.flushOut.bits.ftqIdx := deqDispatchData.ftqIdx
606  io.flushOut.bits.ftqOffset := deqDispatchData.ftqOffset
607  io.flushOut.bits.level := Mux(deqHasReplayInst || intrEnable || exceptionEnable, RedirectLevel.flush, RedirectLevel.flushAfter) // TODO use this to implement "exception next"
608  io.flushOut.bits.interrupt := true.B
609  XSPerfAccumulate("interrupt_num", io.flushOut.valid && intrEnable)
610  XSPerfAccumulate("exception_num", io.flushOut.valid && exceptionEnable)
611  XSPerfAccumulate("flush_pipe_num", io.flushOut.valid && isFlushPipe)
612  XSPerfAccumulate("replay_inst_num", io.flushOut.valid && isFlushPipe && deqHasReplayInst)
613
614  val exceptionHappen = (state === s_idle) && valid(deqPtr.value) && (intrEnable || exceptionEnable) && !lastCycleFlush
615  io.exception.valid := RegNext(exceptionHappen)
616  io.exception.bits.uop := RegEnable(debug_deqUop, exceptionHappen)
617  io.exception.bits.uop.ctrl.commitType := RegEnable(deqDispatchData.commitType, exceptionHappen)
618  io.exception.bits.uop.cf.exceptionVec := RegEnable(exceptionDataRead.bits.exceptionVec, exceptionHappen)
619  io.exception.bits.uop.ctrl.singleStep := RegEnable(exceptionDataRead.bits.singleStep, exceptionHappen)
620  io.exception.bits.uop.cf.crossPageIPFFix := RegEnable(exceptionDataRead.bits.crossPageIPFFix, exceptionHappen)
621  io.exception.bits.isInterrupt := RegEnable(intrEnable, exceptionHappen)
622  io.exception.bits.uop.cf.trigger := RegEnable(exceptionDataRead.bits.trigger, exceptionHappen)
623
624  XSDebug(io.flushOut.valid,
625    p"generate redirect: pc 0x${Hexadecimal(io.exception.bits.uop.cf.pc)} intr $intrEnable " +
626    p"excp $exceptionEnable flushPipe $isFlushPipe " +
627    p"Trap_target 0x${Hexadecimal(io.csr.trapTarget)} exceptionVec ${Binary(exceptionDataRead.bits.exceptionVec.asUInt)}\n")
628
629
630  /**
631    * Commits (and walk)
632    * They share the same width.
633    */
634  val walkCounter = Reg(UInt(log2Up(RobSize + 1).W))
635  val shouldWalkVec = VecInit((0 until CommitWidth).map(_.U < walkCounter))
636  val walkFinished = walkCounter <= CommitWidth.U
637
638  require(RenameWidth <= CommitWidth)
639
640  // wiring to csr
641  val (wflags, fpWen) = (0 until CommitWidth).map(i => {
642    val v = io.commits.commitValid(i)
643    val info = io.commits.info(i)
644    (v & info.wflags, v & info.fpWen)
645  }).unzip
646  val fflags = Wire(Valid(UInt(5.W)))
647  fflags.valid := io.commits.isCommit && VecInit(wflags).asUInt.orR
648  fflags.bits := wflags.zip(fflagsDataRead).map({
649    case (w, f) => Mux(w, f, 0.U)
650  }).reduce(_|_)
651  val dirty_fs = io.commits.isCommit && VecInit(fpWen).asUInt.orR
652
653  // when mispredict branches writeback, stop commit in the next 2 cycles
654  // TODO: don't check all exu write back
655  val misPredWb = Cat(VecInit(exuWriteback.map(wb =>
656    wb.bits.redirect.cfiUpdate.isMisPred && wb.bits.redirectValid
657  ))).orR
658  val misPredBlockCounter = Reg(UInt(3.W))
659  misPredBlockCounter := Mux(misPredWb,
660    "b111".U,
661    misPredBlockCounter >> 1.U
662  )
663  val misPredBlock = misPredBlockCounter(0)
664  val blockCommit = misPredBlock || isReplaying || lastCycleFlush || hasWFI
665
666  io.commits.isWalk := state === s_walk
667  io.commits.isCommit := state === s_idle && !blockCommit
668  val walk_v = VecInit(walkPtrVec.map(ptr => valid(ptr.value)))
669  val commit_v = VecInit(deqPtrVec.map(ptr => valid(ptr.value)))
670  // store will be commited iff both sta & std have been writebacked
671  val commit_w = VecInit(deqPtrVec.map(ptr => writebacked(ptr.value) && store_data_writebacked(ptr.value)))
672  val commit_exception = exceptionDataRead.valid && !isAfter(exceptionDataRead.bits.robIdx, deqPtrVec.last)
673  val commit_block = VecInit((0 until CommitWidth).map(i => !commit_w(i)))
674  val allowOnlyOneCommit = commit_exception || intrBitSetReg
675  // for instructions that may block others, we don't allow them to commit
676  for (i <- 0 until CommitWidth) {
677    // defaults: state === s_idle and instructions commit
678    // when intrBitSetReg, allow only one instruction to commit at each clock cycle
679    val isBlocked = if (i != 0) Cat(commit_block.take(i)).orR || allowOnlyOneCommit else intrEnable || deqHasException || deqHasReplayInst
680    io.commits.commitValid(i) := commit_v(i) && commit_w(i) && !isBlocked
681    io.commits.info(i)  := dispatchDataRead(i)
682
683    when (state === s_walk) {
684      io.commits.walkValid(i) := shouldWalkVec(i)
685      when (io.commits.isWalk && state === s_walk && shouldWalkVec(i)) {
686        XSError(!walk_v(i), s"why not $i???\n")
687      }
688    }
689
690    XSInfo(io.commits.isCommit && io.commits.commitValid(i),
691      "retired pc %x wen %d ldest %d pdest %x old_pdest %x data %x fflags: %b\n",
692      debug_microOp(deqPtrVec(i).value).cf.pc,
693      io.commits.info(i).rfWen,
694      io.commits.info(i).ldest,
695      io.commits.info(i).pdest,
696      io.commits.info(i).old_pdest,
697      debug_exuData(deqPtrVec(i).value),
698      fflagsDataRead(i)
699    )
700    XSInfo(state === s_walk && io.commits.walkValid(i), "walked pc %x wen %d ldst %d data %x\n",
701      debug_microOp(walkPtrVec(i).value).cf.pc,
702      io.commits.info(i).rfWen,
703      io.commits.info(i).ldest,
704      debug_exuData(walkPtrVec(i).value)
705    )
706  }
707  if (env.EnableDifftest) {
708    io.commits.info.map(info => dontTouch(info.pc))
709  }
710
711  // sync fflags/dirty_fs to csr
712  io.csr.fflags := RegNext(fflags)
713  io.csr.dirty_fs := RegNext(dirty_fs)
714
715  // commit load/store to lsq
716  val ldCommitVec = VecInit((0 until CommitWidth).map(i => io.commits.commitValid(i) && io.commits.info(i).commitType === CommitType.LOAD))
717  val stCommitVec = VecInit((0 until CommitWidth).map(i => io.commits.commitValid(i) && io.commits.info(i).commitType === CommitType.STORE))
718  io.lsq.lcommit := RegNext(Mux(io.commits.isCommit, PopCount(ldCommitVec), 0.U))
719  io.lsq.scommit := RegNext(Mux(io.commits.isCommit, PopCount(stCommitVec), 0.U))
720  // indicate a pending load or store
721  io.lsq.pendingld := RegNext(io.commits.isCommit && io.commits.info(0).commitType === CommitType.LOAD && valid(deqPtr.value))
722  io.lsq.pendingst := RegNext(io.commits.isCommit && io.commits.info(0).commitType === CommitType.STORE && valid(deqPtr.value))
723  io.lsq.commit := RegNext(io.commits.isCommit && io.commits.commitValid(0))
724
725  /**
726    * state changes
727    * (1) redirect: switch to s_walk
728    * (2) walk: when walking comes to the end, switch to s_idle
729    */
730  val state_next = Mux(io.redirect.valid, s_walk, Mux(state === s_walk && walkFinished, s_idle, state))
731  XSPerfAccumulate("s_idle_to_idle",            state === s_idle && state_next === s_idle)
732  XSPerfAccumulate("s_idle_to_walk",            state === s_idle && state_next === s_walk)
733  XSPerfAccumulate("s_walk_to_idle",            state === s_walk && state_next === s_idle)
734  XSPerfAccumulate("s_walk_to_walk",            state === s_walk && state_next === s_walk)
735  state := state_next
736
737  /**
738    * pointers and counters
739    */
740  val deqPtrGenModule = Module(new RobDeqPtrWrapper)
741  deqPtrGenModule.io.state := state
742  deqPtrGenModule.io.deq_v := commit_v
743  deqPtrGenModule.io.deq_w := commit_w
744  deqPtrGenModule.io.exception_state := exceptionDataRead
745  deqPtrGenModule.io.intrBitSetReg := intrBitSetReg
746  deqPtrGenModule.io.hasNoSpecExec := hasNoSpecExec
747  deqPtrGenModule.io.interrupt_safe := interrupt_safe(deqPtr.value)
748  deqPtrGenModule.io.blockCommit := blockCommit
749  deqPtrVec := deqPtrGenModule.io.out
750  val deqPtrVec_next = deqPtrGenModule.io.next_out
751
752  val enqPtrGenModule = Module(new RobEnqPtrWrapper)
753  enqPtrGenModule.io.redirect := io.redirect
754  enqPtrGenModule.io.allowEnqueue := allowEnqueue
755  enqPtrGenModule.io.hasBlockBackward := hasBlockBackward
756  enqPtrGenModule.io.enq := VecInit(io.enq.req.map(_.valid))
757  enqPtrVec := enqPtrGenModule.io.out
758
759  val thisCycleWalkCount = Mux(walkFinished, walkCounter, CommitWidth.U)
760  // next walkPtrVec:
761  // (1) redirect occurs: update according to state
762  // (2) walk: move forwards
763  val walkPtrVec_next = Mux(io.redirect.valid,
764    deqPtrVec_next,
765    Mux(state === s_walk, VecInit(walkPtrVec.map(_ + CommitWidth.U)), walkPtrVec)
766  )
767  walkPtrVec := walkPtrVec_next
768
769  val numValidEntries = distanceBetween(enqPtr, deqPtr)
770  val commitCnt = PopCount(io.commits.commitValid)
771
772  allowEnqueue := numValidEntries + dispatchNum <= (RobSize - RenameWidth).U
773
774  val currentWalkPtr = Mux(state === s_walk, walkPtr, deqPtrVec_next(0))
775  val redirectWalkDistance = distanceBetween(io.redirect.bits.robIdx, deqPtrVec_next(0))
776  when (io.redirect.valid) {
777    // full condition:
778    // +& is used here because:
779    // When rob is full and the tail instruction causes a misprediction,
780    // the redirect robIdx is the deqPtr - 1. In this case, redirectWalkDistance
781    // is RobSize - 1.
782    // Since misprediction does not flush the instruction itself, flushItSelf is false.B.
783    // Previously we use `+` to count the walk distance and it causes overflows
784    // when RobSize is power of 2. We change it to `+&` to allow walkCounter to be RobSize.
785    // The width of walkCounter also needs to be changed.
786    // empty condition:
787    // When the last instruction in ROB commits and causes a flush, a redirect
788    // will be raised later. In such circumstances, the redirect robIdx is before
789    // the deqPtrVec_next(0) and will cause underflow.
790    walkCounter := Mux(isBefore(io.redirect.bits.robIdx, deqPtrVec_next(0)), 0.U,
791                       redirectWalkDistance +& !io.redirect.bits.flushItself())
792  }.elsewhen (state === s_walk) {
793    walkCounter := walkCounter - thisCycleWalkCount
794    XSInfo(p"rolling back: $enqPtr $deqPtr walk $walkPtr walkcnt $walkCounter\n")
795  }
796
797
798  /**
799    * States
800    * We put all the stage bits changes here.
801
802    * All events: (1) enqueue (dispatch); (2) writeback; (3) cancel; (4) dequeue (commit);
803    * All states: (1) valid; (2) writebacked; (3) flagBkup
804    */
805  val commitReadAddr = Mux(state === s_idle, VecInit(deqPtrVec.map(_.value)), VecInit(walkPtrVec.map(_.value)))
806
807  // redirect logic writes 6 valid
808  val redirectHeadVec = Reg(Vec(RenameWidth, new RobPtr))
809  val redirectTail = Reg(new RobPtr)
810  val redirectIdle :: redirectBusy :: Nil = Enum(2)
811  val redirectState = RegInit(redirectIdle)
812  val invMask = redirectHeadVec.map(redirectHead => isBefore(redirectHead, redirectTail))
813  when(redirectState === redirectBusy) {
814    redirectHeadVec.foreach(redirectHead => redirectHead := redirectHead + RenameWidth.U)
815    redirectHeadVec zip invMask foreach {
816      case (redirectHead, inv) => when(inv) {
817        valid(redirectHead.value) := false.B
818      }
819    }
820    when(!invMask.last) {
821      redirectState := redirectIdle
822    }
823  }
824  when(io.redirect.valid) {
825    redirectState := redirectBusy
826    when(redirectState === redirectIdle) {
827      redirectTail := enqPtr
828    }
829    redirectHeadVec.zipWithIndex.foreach { case (redirectHead, i) =>
830      redirectHead := Mux(io.redirect.bits.flushItself(), io.redirect.bits.robIdx + i.U, io.redirect.bits.robIdx + (i + 1).U)
831    }
832  }
833  // enqueue logic writes 6 valid
834  for (i <- 0 until RenameWidth) {
835    when (canEnqueue(i) && !io.redirect.valid) {
836      valid(allocatePtrVec(i).value) := true.B
837    }
838  }
839  // dequeue logic writes 6 valid
840  for (i <- 0 until CommitWidth) {
841    val commitValid = io.commits.isCommit && io.commits.commitValid(i)
842    when (commitValid) {
843      valid(commitReadAddr(i)) := false.B
844    }
845  }
846
847  // debug_inst update
848  for(i <- 0 until (exuParameters.LduCnt + exuParameters.StuCnt)) {
849    debug_lsInfo(io.debug_ls.debugLsInfo(i).s1_robIdx).s1SignalEnable(io.debug_ls.debugLsInfo(i))
850    debug_lsInfo(io.debug_ls.debugLsInfo(i).s2_robIdx).s2SignalEnable(io.debug_ls.debugLsInfo(i))
851  }
852
853  // status field: writebacked
854  // enqueue logic set 6 writebacked to false
855  for (i <- 0 until RenameWidth) {
856    when (canEnqueue(i)) {
857      val enqHasException = ExceptionNO.selectFrontend(io.enq.req(i).bits.cf.exceptionVec).asUInt.orR
858      val enqHasTriggerHit = io.enq.req(i).bits.cf.trigger.getHitFrontend
859      val enqIsWritebacked = io.enq.req(i).bits.eliminatedMove
860      writebacked(allocatePtrVec(i).value) := enqIsWritebacked && !enqHasException && !enqHasTriggerHit
861      val isStu = io.enq.req(i).bits.ctrl.fuType === FuType.stu
862      store_data_writebacked(allocatePtrVec(i).value) := !isStu
863    }
864  }
865  when (exceptionGen.io.out.valid) {
866    val wbIdx = exceptionGen.io.out.bits.robIdx.value
867    writebacked(wbIdx) := true.B
868    store_data_writebacked(wbIdx) := true.B
869  }
870  // writeback logic set numWbPorts writebacked to true
871  for ((wb, cfgs) <- exuWriteback.zip(wbExuConfigs(exeWbSel))) {
872    when (wb.valid) {
873      val wbIdx = wb.bits.uop.robIdx.value
874      val wbHasException = ExceptionNO.selectByExu(wb.bits.uop.cf.exceptionVec, cfgs).asUInt.orR
875      val wbHasTriggerHit = wb.bits.uop.cf.trigger.getHitBackend
876      val wbHasFlushPipe = cfgs.exists(_.flushPipe).B && wb.bits.uop.ctrl.flushPipe
877      val wbHasReplayInst = cfgs.exists(_.replayInst).B && wb.bits.uop.ctrl.replayInst
878      val block_wb = wbHasException || wbHasFlushPipe || wbHasReplayInst || wbHasTriggerHit
879      writebacked(wbIdx) := !block_wb
880    }
881  }
882  // store data writeback logic mark store as data_writebacked
883  for (wb <- stdWriteback) {
884    when(RegNext(wb.valid)) {
885      store_data_writebacked(RegNext(wb.bits.uop.robIdx.value)) := true.B
886    }
887  }
888
889  // flagBkup
890  // enqueue logic set 6 flagBkup at most
891  for (i <- 0 until RenameWidth) {
892    when (canEnqueue(i)) {
893      flagBkup(allocatePtrVec(i).value) := allocatePtrVec(i).flag
894    }
895  }
896
897  // interrupt_safe
898  for (i <- 0 until RenameWidth) {
899    // We RegNext the updates for better timing.
900    // Note that instructions won't change the system's states in this cycle.
901    when (RegNext(canEnqueue(i))) {
902      // For now, we allow non-load-store instructions to trigger interrupts
903      // For MMIO instructions, they should not trigger interrupts since they may
904      // be sent to lower level before it writes back.
905      // However, we cannot determine whether a load/store instruction is MMIO.
906      // Thus, we don't allow load/store instructions to trigger an interrupt.
907      // TODO: support non-MMIO load-store instructions to trigger interrupts
908      val allow_interrupts = !CommitType.isLoadStore(io.enq.req(i).bits.ctrl.commitType)
909      interrupt_safe(RegNext(allocatePtrVec(i).value)) := RegNext(allow_interrupts)
910    }
911  }
912
913  /**
914    * read and write of data modules
915    */
916  val commitReadAddr_next = Mux(state_next === s_idle,
917    VecInit(deqPtrVec_next.map(_.value)),
918    VecInit(walkPtrVec_next.map(_.value))
919  )
920  // NOTE: dispatch info will record the uop of inst
921  dispatchData.io.wen := canEnqueue
922  dispatchData.io.waddr := allocatePtrVec.map(_.value)
923  dispatchData.io.wdata.zip(io.enq.req.map(_.bits)).foreach{ case (wdata, req) =>
924    wdata.ldest := req.ctrl.ldest
925    wdata.rfWen := req.ctrl.rfWen
926    wdata.fpWen := req.ctrl.fpWen
927    wdata.wflags := req.ctrl.fpu.wflags
928    wdata.commitType := req.ctrl.commitType
929    wdata.pdest := req.pdest
930    wdata.old_pdest := req.old_pdest
931    wdata.ftqIdx := req.cf.ftqPtr
932    wdata.ftqOffset := req.cf.ftqOffset
933    wdata.isMove := req.eliminatedMove
934    wdata.pc := req.cf.pc
935  }
936  dispatchData.io.raddr := commitReadAddr_next
937
938  exceptionGen.io.redirect <> io.redirect
939  exceptionGen.io.flush := io.flushOut.valid
940  for (i <- 0 until RenameWidth) {
941    exceptionGen.io.enq(i).valid := canEnqueue(i)
942    exceptionGen.io.enq(i).bits.robIdx := io.enq.req(i).bits.robIdx
943    exceptionGen.io.enq(i).bits.exceptionVec := ExceptionNO.selectFrontend(io.enq.req(i).bits.cf.exceptionVec)
944    exceptionGen.io.enq(i).bits.flushPipe := io.enq.req(i).bits.ctrl.flushPipe
945    exceptionGen.io.enq(i).bits.replayInst := false.B
946    XSError(canEnqueue(i) && io.enq.req(i).bits.ctrl.replayInst, "enq should not set replayInst")
947    exceptionGen.io.enq(i).bits.singleStep := io.enq.req(i).bits.ctrl.singleStep
948    exceptionGen.io.enq(i).bits.crossPageIPFFix := io.enq.req(i).bits.cf.crossPageIPFFix
949    exceptionGen.io.enq(i).bits.trigger.clear()
950    exceptionGen.io.enq(i).bits.trigger.frontendHit := io.enq.req(i).bits.cf.trigger.frontendHit
951  }
952
953  println(s"ExceptionGen:")
954  val exceptionCases = exceptionPorts.map(_._1.flatMap(_.exceptionOut).distinct.sorted)
955  require(exceptionCases.length == exceptionGen.io.wb.length)
956  for ((((configs, wb), exc_wb), i) <- exceptionPorts.zip(exceptionGen.io.wb).zipWithIndex) {
957    exc_wb.valid                := wb.valid
958    exc_wb.bits.robIdx          := wb.bits.uop.robIdx
959    exc_wb.bits.exceptionVec    := ExceptionNO.selectByExu(wb.bits.uop.cf.exceptionVec, configs)
960    exc_wb.bits.flushPipe       := configs.exists(_.flushPipe).B && wb.bits.uop.ctrl.flushPipe
961    exc_wb.bits.replayInst      := configs.exists(_.replayInst).B && wb.bits.uop.ctrl.replayInst
962    exc_wb.bits.singleStep      := false.B
963    exc_wb.bits.crossPageIPFFix := false.B
964    // TODO: make trigger configurable
965    exc_wb.bits.trigger.clear()
966    exc_wb.bits.trigger.backendHit := wb.bits.uop.cf.trigger.backendHit
967    println(s"  [$i] ${configs.map(_.name)}: exception ${exceptionCases(i)}, " +
968      s"flushPipe ${configs.exists(_.flushPipe)}, " +
969      s"replayInst ${configs.exists(_.replayInst)}")
970  }
971
972  val fflags_wb = fflagsPorts.map(_._2)
973  val fflagsDataModule = Module(new SyncDataModuleTemplate(
974    UInt(5.W), RobSize, CommitWidth, fflags_wb.size)
975  )
976  for(i <- fflags_wb.indices){
977    fflagsDataModule.io.wen  (i) := fflags_wb(i).valid
978    fflagsDataModule.io.waddr(i) := fflags_wb(i).bits.uop.robIdx.value
979    fflagsDataModule.io.wdata(i) := fflags_wb(i).bits.fflags
980  }
981  fflagsDataModule.io.raddr := VecInit(deqPtrVec_next.map(_.value))
982  fflagsDataRead := fflagsDataModule.io.rdata
983
984  val instrCntReg = RegInit(0.U(64.W))
985  val fuseCommitCnt = PopCount(io.commits.commitValid.zip(io.commits.info).map{ case (v, i) => RegNext(v && CommitType.isFused(i.commitType)) })
986  val trueCommitCnt = RegNext(commitCnt) +& fuseCommitCnt
987  val retireCounter = Mux(RegNext(io.commits.isCommit), trueCommitCnt, 0.U)
988  val instrCnt = instrCntReg + retireCounter
989  instrCntReg := instrCnt
990  io.csr.perfinfo.retiredInstr := retireCounter
991  io.robFull := !allowEnqueue
992
993  /**
994    * debug info
995    */
996  XSDebug(p"enqPtr ${enqPtr} deqPtr ${deqPtr}\n")
997  XSDebug("")
998  for(i <- 0 until RobSize){
999    XSDebug(false, !valid(i), "-")
1000    XSDebug(false, valid(i) && writebacked(i), "w")
1001    XSDebug(false, valid(i) && !writebacked(i), "v")
1002  }
1003  XSDebug(false, true.B, "\n")
1004
1005  for(i <- 0 until RobSize) {
1006    if(i % 4 == 0) XSDebug("")
1007    XSDebug(false, true.B, "%x ", debug_microOp(i).cf.pc)
1008    XSDebug(false, !valid(i), "- ")
1009    XSDebug(false, valid(i) && writebacked(i), "w ")
1010    XSDebug(false, valid(i) && !writebacked(i), "v ")
1011    if(i % 4 == 3) XSDebug(false, true.B, "\n")
1012  }
1013
1014  def ifCommit(counter: UInt): UInt = Mux(io.commits.isCommit, counter, 0.U)
1015  def ifCommitReg(counter: UInt): UInt = Mux(RegNext(io.commits.isCommit), counter, 0.U)
1016
1017  val commitDebugExu = deqPtrVec.map(_.value).map(debug_exuDebug(_))
1018  val commitDebugUop = deqPtrVec.map(_.value).map(debug_microOp(_))
1019  val commitDebugLsInfo = deqPtrVec.map(_.value).map(debug_lsInfo(_))
1020  XSPerfAccumulate("clock_cycle", 1.U)
1021  QueuePerf(RobSize, PopCount((0 until RobSize).map(valid(_))), !allowEnqueue)
1022  XSPerfAccumulate("commitUop", ifCommit(commitCnt))
1023  XSPerfAccumulate("commitInstr", ifCommitReg(trueCommitCnt))
1024  val commitIsMove = commitDebugUop.map(_.ctrl.isMove)
1025  XSPerfAccumulate("commitInstrMove", ifCommit(PopCount(io.commits.commitValid.zip(commitIsMove).map{ case (v, m) => v && m })))
1026  val commitMoveElim = commitDebugUop.map(_.debugInfo.eliminatedMove)
1027  XSPerfAccumulate("commitInstrMoveElim", ifCommit(PopCount(io.commits.commitValid zip commitMoveElim map { case (v, e) => v && e })))
1028  XSPerfAccumulate("commitInstrFused", ifCommitReg(fuseCommitCnt))
1029  val commitIsLoad = io.commits.info.map(_.commitType).map(_ === CommitType.LOAD)
1030  val commitLoadValid = io.commits.commitValid.zip(commitIsLoad).map{ case (v, t) => v && t }
1031  XSPerfAccumulate("commitInstrLoad", ifCommit(PopCount(commitLoadValid)))
1032  val commitIsBranch = io.commits.info.map(_.commitType).map(_ === CommitType.BRANCH)
1033  val commitBranchValid = io.commits.commitValid.zip(commitIsBranch).map{ case (v, t) => v && t }
1034  XSPerfAccumulate("commitInstrBranch", ifCommit(PopCount(commitBranchValid)))
1035  val commitLoadWaitBit = commitDebugUop.map(_.cf.loadWaitBit)
1036  XSPerfAccumulate("commitInstrLoadWait", ifCommit(PopCount(commitLoadValid.zip(commitLoadWaitBit).map{ case (v, w) => v && w })))
1037  val commitIsStore = io.commits.info.map(_.commitType).map(_ === CommitType.STORE)
1038  XSPerfAccumulate("commitInstrStore", ifCommit(PopCount(io.commits.commitValid.zip(commitIsStore).map{ case (v, t) => v && t })))
1039  XSPerfAccumulate("writeback", PopCount((0 until RobSize).map(i => valid(i) && writebacked(i))))
1040  // XSPerfAccumulate("enqInstr", PopCount(io.dp1Req.map(_.fire)))
1041  // XSPerfAccumulate("d2rVnR", PopCount(io.dp1Req.map(p => p.valid && !p.ready)))
1042  XSPerfAccumulate("walkInstr", Mux(io.commits.isWalk, PopCount(io.commits.walkValid), 0.U))
1043  XSPerfAccumulate("walkCycle", state === s_walk)
1044  val deqNotWritebacked = valid(deqPtr.value) && !writebacked(deqPtr.value)
1045  val deqUopCommitType = io.commits.info(0).commitType
1046  XSPerfAccumulate("waitNormalCycle", deqNotWritebacked && deqUopCommitType === CommitType.NORMAL)
1047  XSPerfAccumulate("waitBranchCycle", deqNotWritebacked && deqUopCommitType === CommitType.BRANCH)
1048  XSPerfAccumulate("waitLoadCycle", deqNotWritebacked && deqUopCommitType === CommitType.LOAD)
1049  XSPerfAccumulate("waitStoreCycle", deqNotWritebacked && deqUopCommitType === CommitType.STORE)
1050  XSPerfAccumulate("robHeadPC", io.commits.info(0).pc)
1051  val dispatchLatency = commitDebugUop.map(uop => uop.debugInfo.dispatchTime - uop.debugInfo.renameTime)
1052  val enqRsLatency = commitDebugUop.map(uop => uop.debugInfo.enqRsTime - uop.debugInfo.dispatchTime)
1053  val selectLatency = commitDebugUop.map(uop => uop.debugInfo.selectTime - uop.debugInfo.enqRsTime)
1054  val issueLatency = commitDebugUop.map(uop => uop.debugInfo.issueTime - uop.debugInfo.selectTime)
1055  val executeLatency = commitDebugUop.map(uop => uop.debugInfo.writebackTime - uop.debugInfo.issueTime)
1056  val rsFuLatency = commitDebugUop.map(uop => uop.debugInfo.writebackTime - uop.debugInfo.enqRsTime)
1057  val commitLatency = commitDebugUop.map(uop => timer - uop.debugInfo.writebackTime)
1058  val accessLatency = commitDebugUop.map(uop => uop.debugInfo.writebackTime - uop.debugInfo.issueTime)
1059  val tlbLatency = commitDebugUop.map(uop => uop.debugInfo.tlbRespTime - uop.debugInfo.tlbFirstReqTime)
1060  def latencySum(cond: Seq[Bool], latency: Seq[UInt]): UInt = {
1061    cond.zip(latency).map(x => Mux(x._1, x._2, 0.U)).reduce(_ +& _)
1062  }
1063  for (fuType <- FuType.functionNameMap.keys) {
1064    val fuName = FuType.functionNameMap(fuType)
1065    val commitIsFuType = io.commits.commitValid.zip(commitDebugUop).map(x => x._1 && x._2.ctrl.fuType === fuType.U )
1066    XSPerfAccumulate(s"${fuName}_instr_cnt", ifCommit(PopCount(commitIsFuType)))
1067    XSPerfAccumulate(s"${fuName}_latency_dispatch", ifCommit(latencySum(commitIsFuType, dispatchLatency)))
1068    XSPerfAccumulate(s"${fuName}_latency_enq_rs", ifCommit(latencySum(commitIsFuType, enqRsLatency)))
1069    XSPerfAccumulate(s"${fuName}_latency_select", ifCommit(latencySum(commitIsFuType, selectLatency)))
1070    XSPerfAccumulate(s"${fuName}_latency_issue", ifCommit(latencySum(commitIsFuType, issueLatency)))
1071    XSPerfAccumulate(s"${fuName}_latency_execute", ifCommit(latencySum(commitIsFuType, executeLatency)))
1072    XSPerfAccumulate(s"${fuName}_latency_enq_rs_execute", ifCommit(latencySum(commitIsFuType, rsFuLatency)))
1073    XSPerfAccumulate(s"${fuName}_latency_commit", ifCommit(latencySum(commitIsFuType, commitLatency)))
1074    if (fuType == FuType.fmac.litValue) {
1075      val commitIsFma = commitIsFuType.zip(commitDebugUop).map(x => x._1 && x._2.ctrl.fpu.ren3 )
1076      XSPerfAccumulate(s"${fuName}_instr_cnt_fma", ifCommit(PopCount(commitIsFma)))
1077      XSPerfAccumulate(s"${fuName}_latency_enq_rs_execute_fma", ifCommit(latencySum(commitIsFma, rsFuLatency)))
1078      XSPerfAccumulate(s"${fuName}_latency_execute_fma", ifCommit(latencySum(commitIsFma, executeLatency)))
1079    }
1080  }
1081
1082  if (env.EnableTopDown) {
1083    ExcitingUtils.addSource(commit_v(0) && !commit_w(0) && state =/= s_walk && io.commits.info(0).commitType === CommitType.LOAD,
1084                            "rob_first_load", ExcitingUtils.Perf)
1085    ExcitingUtils.addSource(commit_v(0) && !commit_w(0) && state =/= s_walk && io.commits.info(0).commitType === CommitType.STORE,
1086                            "rob_first_store", ExcitingUtils.Perf)
1087  }
1088
1089  /**
1090    * DataBase info:
1091    * log trigger is at writeback valid
1092    * */
1093  if(!env.FPGAPlatform){
1094    val isWriteInstInfoTable = WireInit(Constantin.createRecord("isWriteInstInfoTable" + p(XSCoreParamsKey).HartId.toString))
1095    val instTableName = "InstTable" + p(XSCoreParamsKey).HartId.toString
1096    val instSiteName = "Rob" + p(XSCoreParamsKey).HartId.toString
1097    val debug_instTable = ChiselDB.createTable(instTableName, new InstInfoEntry)
1098    // FIXME lyq: only get inst (alu, bj, ls) in exuWriteback
1099    for (wb <- exuWriteback) {
1100      when(wb.valid) {
1101        val debug_instData = Wire(new InstInfoEntry)
1102        val idx = wb.bits.uop.robIdx.value
1103        debug_instData.globalID := wb.bits.uop.ctrl.debug_globalID
1104        debug_instData.robIdx := idx
1105        debug_instData.instType := wb.bits.uop.ctrl.fuType
1106        debug_instData.ivaddr := wb.bits.uop.cf.pc
1107        debug_instData.dvaddr := wb.bits.debug.vaddr
1108        debug_instData.dpaddr := wb.bits.debug.paddr
1109        debug_instData.tlbLatency := wb.bits.uop.debugInfo.tlbRespTime - wb.bits.uop.debugInfo.tlbFirstReqTime
1110        debug_instData.accessLatency := wb.bits.uop.debugInfo.writebackTime - wb.bits.uop.debugInfo.issueTime
1111        debug_instData.executeLatency := wb.bits.uop.debugInfo.writebackTime - wb.bits.uop.debugInfo.issueTime
1112        debug_instData.issueLatency := wb.bits.uop.debugInfo.issueTime - wb.bits.uop.debugInfo.selectTime
1113        debug_instData.exceptType := Cat(wb.bits.uop.cf.exceptionVec)
1114        debug_instData.lsInfo := debug_lsInfo(idx)
1115        debug_instData.mdpInfo.ssid := wb.bits.uop.cf.ssid
1116        debug_instData.mdpInfo.waitAllStore := wb.bits.uop.cf.loadWaitStrict && wb.bits.uop.cf.loadWaitBit
1117        debug_instData.issueTime := wb.bits.uop.debugInfo.issueTime
1118        debug_instData.writebackTime := wb.bits.uop.debugInfo.writebackTime
1119        debug_instTable.log(
1120          data = debug_instData,
1121          en = wb.valid,
1122          site = instSiteName,
1123          clock = clock,
1124          reset = reset
1125        )
1126      }
1127    }
1128  }
1129
1130
1131  //difftest signals
1132  val firstValidCommit = (deqPtr + PriorityMux(io.commits.commitValid, VecInit(List.tabulate(CommitWidth)(_.U(log2Up(CommitWidth).W))))).value
1133
1134  val wdata = Wire(Vec(CommitWidth, UInt(XLEN.W)))
1135  val wpc = Wire(Vec(CommitWidth, UInt(XLEN.W)))
1136
1137  for(i <- 0 until CommitWidth) {
1138    val idx = deqPtrVec(i).value
1139    wdata(i) := debug_exuData(idx)
1140    wpc(i) := SignExt(commitDebugUop(i).cf.pc, XLEN)
1141  }
1142
1143  if (env.EnableDifftest) {
1144    for (i <- 0 until CommitWidth) {
1145      val difftest = Module(new DifftestInstrCommit)
1146      // assgin default value
1147      difftest.io := DontCare
1148
1149      difftest.io.clock    := clock
1150      difftest.io.coreid   := io.hartId
1151      difftest.io.index    := i.U
1152
1153      val ptr = deqPtrVec(i).value
1154      val uop = commitDebugUop(i)
1155      val exuOut = debug_exuDebug(ptr)
1156      val exuData = debug_exuData(ptr)
1157      difftest.io.valid    := RegNext(RegNext(RegNext(io.commits.commitValid(i) && io.commits.isCommit)))
1158      difftest.io.pc       := RegNext(RegNext(RegNext(SignExt(uop.cf.pc, XLEN))))
1159      difftest.io.instr    := RegNext(RegNext(RegNext(uop.cf.instr)))
1160      difftest.io.robIdx   := RegNext(RegNext(RegNext(ZeroExt(ptr, 10))))
1161      difftest.io.lqIdx    := RegNext(RegNext(RegNext(ZeroExt(uop.lqIdx.value, 7))))
1162      difftest.io.sqIdx    := RegNext(RegNext(RegNext(ZeroExt(uop.sqIdx.value, 7))))
1163      difftest.io.isLoad   := RegNext(RegNext(RegNext(io.commits.info(i).commitType === CommitType.LOAD)))
1164      difftest.io.isStore  := RegNext(RegNext(RegNext(io.commits.info(i).commitType === CommitType.STORE)))
1165      difftest.io.special  := RegNext(RegNext(RegNext(CommitType.isFused(io.commits.info(i).commitType))))
1166      // when committing an eliminated move instruction,
1167      // we must make sure that skip is properly set to false (output from EXU is random value)
1168      difftest.io.skip     := RegNext(RegNext(RegNext(Mux(uop.eliminatedMove, false.B, exuOut.isMMIO || exuOut.isPerfCnt))))
1169      difftest.io.isRVC    := RegNext(RegNext(RegNext(uop.cf.pd.isRVC)))
1170      difftest.io.rfwen    := RegNext(RegNext(RegNext(io.commits.commitValid(i) && io.commits.info(i).rfWen && io.commits.info(i).ldest =/= 0.U)))
1171      difftest.io.fpwen    := RegNext(RegNext(RegNext(io.commits.commitValid(i) && io.commits.info(i).fpWen)))
1172      difftest.io.wpdest   := RegNext(RegNext(RegNext(io.commits.info(i).pdest)))
1173      difftest.io.wdest    := RegNext(RegNext(RegNext(io.commits.info(i).ldest)))
1174
1175      // // runahead commit hint
1176      // val runahead_commit = Module(new DifftestRunaheadCommitEvent)
1177      // runahead_commit.io.clock := clock
1178      // runahead_commit.io.coreid := io.hartId
1179      // runahead_commit.io.index := i.U
1180      // runahead_commit.io.valid := difftest.io.valid &&
1181      //   (commitBranchValid(i) || commitIsStore(i))
1182      // // TODO: is branch or store
1183      // runahead_commit.io.pc    := difftest.io.pc
1184    }
1185  }
1186  else if (env.AlwaysBasicDiff) {
1187    // These are the structures used by difftest only and should be optimized after synthesis.
1188    val dt_eliminatedMove = Mem(RobSize, Bool())
1189    val dt_isRVC = Mem(RobSize, Bool())
1190    val dt_exuDebug = Reg(Vec(RobSize, new DebugBundle))
1191    for (i <- 0 until RenameWidth) {
1192      when (canEnqueue(i)) {
1193        dt_eliminatedMove(allocatePtrVec(i).value) := io.enq.req(i).bits.eliminatedMove
1194        dt_isRVC(allocatePtrVec(i).value) := io.enq.req(i).bits.cf.pd.isRVC
1195      }
1196    }
1197    for (wb <- exuWriteback) {
1198      when (wb.valid) {
1199        val wbIdx = wb.bits.uop.robIdx.value
1200        dt_exuDebug(wbIdx) := wb.bits.debug
1201      }
1202    }
1203    // Always instantiate basic difftest modules.
1204    for (i <- 0 until CommitWidth) {
1205      val commitInfo = io.commits.info(i)
1206      val ptr = deqPtrVec(i).value
1207      val exuOut = dt_exuDebug(ptr)
1208      val eliminatedMove = dt_eliminatedMove(ptr)
1209      val isRVC = dt_isRVC(ptr)
1210
1211      val difftest = Module(new DifftestBasicInstrCommit)
1212      difftest.io.clock   := clock
1213      difftest.io.coreid  := io.hartId
1214      difftest.io.index   := i.U
1215      difftest.io.valid   := RegNext(RegNext(RegNext(io.commits.commitValid(i) && io.commits.isCommit)))
1216      difftest.io.special := RegNext(RegNext(RegNext(CommitType.isFused(commitInfo.commitType))))
1217      difftest.io.skip    := RegNext(RegNext(RegNext(Mux(eliminatedMove, false.B, exuOut.isMMIO || exuOut.isPerfCnt))))
1218      difftest.io.isRVC   := RegNext(RegNext(RegNext(isRVC)))
1219      difftest.io.rfwen   := RegNext(RegNext(RegNext(io.commits.commitValid(i) && commitInfo.rfWen && commitInfo.ldest =/= 0.U)))
1220      difftest.io.fpwen   := RegNext(RegNext(RegNext(io.commits.commitValid(i) && commitInfo.fpWen)))
1221      difftest.io.wpdest  := RegNext(RegNext(RegNext(commitInfo.pdest)))
1222      difftest.io.wdest   := RegNext(RegNext(RegNext(commitInfo.ldest)))
1223    }
1224  }
1225
1226  if (env.EnableDifftest) {
1227    for (i <- 0 until CommitWidth) {
1228      val difftest = Module(new DifftestLoadEvent)
1229      difftest.io.clock  := clock
1230      difftest.io.coreid := io.hartId
1231      difftest.io.index  := i.U
1232
1233      val ptr = deqPtrVec(i).value
1234      val uop = commitDebugUop(i)
1235      val exuOut = debug_exuDebug(ptr)
1236      difftest.io.valid  := RegNext(RegNext(RegNext(io.commits.commitValid(i) && io.commits.isCommit)))
1237      difftest.io.paddr  := RegNext(RegNext(RegNext(exuOut.paddr)))
1238      difftest.io.opType := RegNext(RegNext(RegNext(uop.ctrl.fuOpType)))
1239      difftest.io.fuType := RegNext(RegNext(RegNext(uop.ctrl.fuType)))
1240    }
1241  }
1242
1243  // Always instantiate basic difftest modules.
1244  if (env.EnableDifftest) {
1245    val dt_isXSTrap = Mem(RobSize, Bool())
1246    for (i <- 0 until RenameWidth) {
1247      when (canEnqueue(i)) {
1248        dt_isXSTrap(allocatePtrVec(i).value) := io.enq.req(i).bits.ctrl.isXSTrap
1249      }
1250    }
1251    val trapVec = io.commits.commitValid.zip(deqPtrVec).map{ case (v, d) => io.commits.isCommit && v && dt_isXSTrap(d.value) }
1252    val hitTrap = trapVec.reduce(_||_)
1253    val trapCode = PriorityMux(wdata.zip(trapVec).map(x => x._2 -> x._1))
1254    val trapPC = SignExt(PriorityMux(wpc.zip(trapVec).map(x => x._2 ->x._1)), XLEN)
1255    val difftest = Module(new DifftestTrapEvent)
1256    difftest.io.clock    := clock
1257    difftest.io.coreid   := io.hartId
1258    difftest.io.valid    := hitTrap
1259    difftest.io.code     := trapCode
1260    difftest.io.pc       := trapPC
1261    difftest.io.cycleCnt := timer
1262    difftest.io.instrCnt := instrCnt
1263    difftest.io.hasWFI   := hasWFI
1264  }
1265  else if (env.AlwaysBasicDiff) {
1266    val dt_isXSTrap = Mem(RobSize, Bool())
1267    for (i <- 0 until RenameWidth) {
1268      when (canEnqueue(i)) {
1269        dt_isXSTrap(allocatePtrVec(i).value) := io.enq.req(i).bits.ctrl.isXSTrap
1270      }
1271    }
1272    val trapVec = io.commits.commitValid.zip(deqPtrVec).map{ case (v, d) => io.commits.isCommit && v && dt_isXSTrap(d.value) }
1273    val hitTrap = trapVec.reduce(_||_)
1274    val difftest = Module(new DifftestBasicTrapEvent)
1275    difftest.io.clock    := clock
1276    difftest.io.coreid   := io.hartId
1277    difftest.io.valid    := hitTrap
1278    difftest.io.cycleCnt := timer
1279    difftest.io.instrCnt := instrCnt
1280  }
1281
1282  val validEntriesBanks = (0 until (RobSize + 63) / 64).map(i => RegNext(PopCount(valid.drop(i * 64).take(64))))
1283  val validEntries = RegNext(ParallelOperation(validEntriesBanks, (a: UInt, b: UInt) => a +& b))
1284  val commitMoveVec = VecInit(io.commits.commitValid.zip(commitIsMove).map{ case (v, m) => v && m })
1285  val commitLoadVec = VecInit(commitLoadValid)
1286  val commitBranchVec = VecInit(commitBranchValid)
1287  val commitLoadWaitVec = VecInit(commitLoadValid.zip(commitLoadWaitBit).map{ case (v, w) => v && w })
1288  val commitStoreVec = VecInit(io.commits.commitValid.zip(commitIsStore).map{ case (v, t) => v && t })
1289  val perfEvents = Seq(
1290    ("rob_interrupt_num      ", io.flushOut.valid && intrEnable                                       ),
1291    ("rob_exception_num      ", io.flushOut.valid && exceptionEnable                                  ),
1292    ("rob_flush_pipe_num     ", io.flushOut.valid && isFlushPipe                                      ),
1293    ("rob_replay_inst_num    ", io.flushOut.valid && isFlushPipe && deqHasReplayInst                  ),
1294    ("rob_commitUop          ", ifCommit(commitCnt)                                                   ),
1295    ("rob_commitInstr        ", ifCommitReg(trueCommitCnt)                                            ),
1296    ("rob_commitInstrMove    ", ifCommitReg(PopCount(RegNext(commitMoveVec)))                         ),
1297    ("rob_commitInstrFused   ", ifCommitReg(fuseCommitCnt)                                            ),
1298    ("rob_commitInstrLoad    ", ifCommitReg(PopCount(RegNext(commitLoadVec)))                         ),
1299    ("rob_commitInstrBranch  ", ifCommitReg(PopCount(RegNext(commitBranchVec)))                       ),
1300    ("rob_commitInstrLoadWait", ifCommitReg(PopCount(RegNext(commitLoadWaitVec)))                     ),
1301    ("rob_commitInstrStore   ", ifCommitReg(PopCount(RegNext(commitStoreVec)))                        ),
1302    ("rob_walkInstr          ", Mux(io.commits.isWalk, PopCount(io.commits.walkValid), 0.U)           ),
1303    ("rob_walkCycle          ", (state === s_walk)                                                    ),
1304    ("rob_1_4_valid          ", validEntries <= (RobSize / 4).U                                       ),
1305    ("rob_2_4_valid          ", validEntries >  (RobSize / 4).U && validEntries <= (RobSize / 2).U    ),
1306    ("rob_3_4_valid          ", validEntries >  (RobSize / 2).U && validEntries <= (RobSize * 3 / 4).U),
1307    ("rob_4_4_valid          ", validEntries >  (RobSize * 3 / 4).U                                   ),
1308  )
1309  generatePerfEvent()
1310}
1311