xref: /XiangShan/src/main/scala/xiangshan/frontend/IFU.scala (revision 4a5c11909a711def47806ca398ae706b9f99dd07)
1package xiangshan.frontend
2
3import chisel3._
4import chisel3.util._
5import device.RAMHelper
6import xiangshan._
7import utils._
8
9trait HasIFUConst { this: XSModule =>
10  val resetVector = 0x80000000L//TODO: set reset vec
11  val groupAlign = log2Up(FetchWidth * 4 * 2)
12  def groupPC(pc: UInt): UInt = Cat(pc(VAddrBits-1, groupAlign), 0.U(groupAlign.W))
13  // each 1 bit in mask stands for 2 Bytes
14  def mask(pc: UInt): UInt = (Fill(PredictWidth * 2, 1.U(1.W)) >> pc(groupAlign - 1, 1))(PredictWidth - 1, 0)
15  def snpc(pc: UInt): UInt = pc + (PopCount(mask(pc)) << 1)
16}
17
18class IFUIO extends XSBundle
19{
20  val fetchPacket = DecoupledIO(new FetchPacket)
21  val redirect = Flipped(ValidIO(new Redirect))
22  val outOfOrderBrInfo = Flipped(ValidIO(new BranchUpdateInfo))
23  val inOrderBrInfo = Flipped(ValidIO(new BranchUpdateInfo))
24  val icacheReq = DecoupledIO(new FakeIcacheReq)
25  val icacheResp = Flipped(DecoupledIO(new FakeIcacheResp))
26  val icacheFlush = Output(UInt(2.W))
27}
28
29
30class IFU extends XSModule with HasIFUConst
31{
32  val io = IO(new IFUIO)
33  val bpu = BPU(EnableBPU)
34  val pd = Module(new PreDecode)
35
36  val if2_redirect, if3_redirect, if4_redirect = WireInit(false.B)
37  val if1_flush, if2_flush, if3_flush, if4_flush = WireInit(false.B)
38
39  if4_flush := io.redirect.valid
40  if3_flush := if4_flush || if4_redirect
41  if2_flush := if3_flush || if3_redirect
42  if1_flush := if2_flush || if2_redirect
43
44  //********************** IF1 ****************************//
45  val if1_valid = !reset.asBool
46  val if1_npc = WireInit(0.U(VAddrBits.W))
47  val if2_ready = WireInit(false.B)
48  val if1_fire = if1_valid && (if2_ready || if1_flush) && io.icacheReq.ready
49
50  // val extHist = VecInit(Fill(ExtHistoryLength, RegInit(0.U(1.W))))
51  val extHist = RegInit(VecInit(Seq.fill(ExtHistoryLength)(0.U(1.W))))
52  val headPtr = RegInit(0.U(log2Up(ExtHistoryLength).W))
53  val shiftPtr = WireInit(false.B)
54  val newPtr = Wire(UInt(log2Up(ExtHistoryLength).W))
55  val ptr = Mux(shiftPtr, newPtr, headPtr)
56  when (shiftPtr) { headPtr := newPtr }
57  val hist = Wire(Vec(HistoryLength, UInt(1.W)))
58  for (i <- 0 until HistoryLength) {
59    hist(i) := extHist(ptr + i.U)
60  }
61
62  newPtr := headPtr
63  shiftPtr := false.B
64
65  //********************** IF2 ****************************//
66  val if2_valid = RegEnable(next = if1_valid, init = false.B, enable = if1_fire)
67  val if3_ready = WireInit(false.B)
68  val if2_fire = if2_valid && if3_ready && !if2_flush
69  val if2_pc = RegEnable(next = if1_npc, init = resetVector.U, enable = if1_fire)
70  val if2_snpc = snpc(if2_pc)
71  val if2_histPtr = RegEnable(ptr, if1_fire)
72  if2_ready := if2_fire || !if2_valid || if2_flush
73  when (if2_flush) { if2_valid := if1_fire }
74  .elsewhen (if1_fire) { if2_valid := if1_valid }
75  .elsewhen (if2_fire) { if2_valid := false.B }
76
77  when (RegNext(reset.asBool) && !reset.asBool) {
78    if1_npc := resetVector.U(VAddrBits.W)
79  }.elsewhen (if2_fire) {
80    if1_npc := if2_snpc
81  }.otherwise {
82    if1_npc := RegNext(if1_npc)
83  }
84
85  val if2_bp = bpu.io.out(0).bits
86  if2_redirect := if2_fire && bpu.io.out(0).valid && if2_bp.redirect// && !if2_bp.saveHalfRVI
87  when (if2_redirect) {
88    if1_npc := if2_bp.target
89  }
90
91  when (if2_fire && (if2_bp.takenOnBr || if2_bp.hasNotTakenBrs)) {
92    shiftPtr := true.B
93    newPtr := headPtr - 1.U
94    hist(0) := if2_bp.takenOnBr.asUInt
95    extHist(newPtr) := if2_bp.takenOnBr.asUInt
96  }
97
98  //********************** IF3 ****************************//
99  val if3_valid = RegEnable(next = if2_valid, init = false.B, enable = if2_fire)
100  val if4_ready = WireInit(false.B)
101  val if3_fire = if3_valid && if4_ready && io.icacheResp.valid && !if3_flush
102  val if3_pc = RegEnable(if2_pc, if2_fire)
103  val if3_histPtr = RegEnable(if2_histPtr, if2_fire)
104  if3_ready := if3_fire || !if3_valid || if3_flush
105  when (if3_flush) { if3_valid := false.B }
106  .elsewhen (if2_fire) { if3_valid := if2_valid }
107  .elsewhen (if3_fire) { if3_valid := false.B }
108
109  val if3_bp = bpu.io.out(1).bits
110
111  class PrevHalfInstr extends Bundle {
112    val valid = Bool()
113    val taken = Bool()
114    val fetchpc = UInt(VAddrBits.W) // only for debug
115    val idx = UInt(VAddrBits.W) // only for debug
116    val pc = UInt(VAddrBits.W)
117    val target = UInt(VAddrBits.W)
118    val instr = UInt(16.W)
119    val takenOnBr = Bool()
120  }
121
122  val if3_prevHalfInstr = RegInit(0.U.asTypeOf(new PrevHalfInstr))
123  val if4_prevHalfInstr = Wire(new PrevHalfInstr)
124  when (if4_prevHalfInstr.valid) {
125    if3_prevHalfInstr := if4_prevHalfInstr
126  }
127  val prevHalfInstr = Mux(if4_prevHalfInstr.valid, if4_prevHalfInstr, if3_prevHalfInstr)
128
129  val if3_hasPrevHalfInstr = prevHalfInstr.valid && (prevHalfInstr.pc + 2.U) === if3_pc
130  if3_redirect := if3_fire && bpu.io.out(1).valid && (if3_hasPrevHalfInstr && prevHalfInstr.taken || if3_bp.redirect/* && !if3_bp.saveHalfRVI*/ )
131  when (if3_redirect) {
132    if1_npc := Mux(if3_hasPrevHalfInstr && prevHalfInstr.taken, prevHalfInstr.target, if3_bp.target)
133  }
134
135  when (if3_fire && if3_redirect) {
136    shiftPtr := true.B
137    newPtr := Mux(if3_hasPrevHalfInstr && prevHalfInstr.takenOnBr || if3_bp.takenOnBr || if3_bp.hasNotTakenBrs, if3_histPtr - 1.U, if3_histPtr)
138    hist(0) := Mux(if3_hasPrevHalfInstr && prevHalfInstr.takenOnBr || if3_bp.takenOnBr || if3_bp.hasNotTakenBrs,
139      (if3_hasPrevHalfInstr && prevHalfInstr.takenOnBr || if3_bp.takenOnBr).asUInt,
140      extHist(if3_histPtr))
141    extHist(newPtr) := Mux(if3_hasPrevHalfInstr && prevHalfInstr.takenOnBr || if3_bp.takenOnBr || if3_bp.hasNotTakenBrs,
142      (if3_hasPrevHalfInstr && prevHalfInstr.takenOnBr || if3_bp.takenOnBr).asUInt,
143      extHist(if3_histPtr))
144  }
145
146
147
148  // val prev_half_valid = RegInit(false.B)
149  // val prev_half_redirect = RegInit(false.B)
150  // val prev_half_fetchpc = Reg(UInt(VAddrBits.W))
151  // val prev_half_idx = Reg(UInt(log2Up(PredictWidth).W))
152  // val prev_half_tgt = Reg(UInt(VAddrBits.W))
153  // val prev_half_taken = RegInit(false.B)
154  // val prev_half_instr = Reg(UInt(16.W))
155  // when (if3_flush) {
156  //   prev_half_valid := false.B
157  //   prev_half_redirect := false.B
158  // }.elsewhen (if3_fire && if3_bp.saveHalfRVI) {
159  //   prev_half_valid := true.B
160  //   prev_half_redirect := if3_bp.redirect && bpu.io.out(1).valid
161  //   prev_half_fetchpc := if3_pc
162  //   val idx = Mux(if3_bp.redirect && bpu.io.out(1).valid, if3_bp.jmpIdx, PopCount(mask(if3_pc)) - 1.U)
163  //   prev_half_idx := idx
164  //   prev_half_tgt := if3_bp.target
165  //   prev_half_taken := if3_bp.taken
166  //   prev_half_instr := pd.io.out.instrs(idx)(15, 0)
167  // }.elsewhen (if3_fire) {
168  //   prev_half_valid := false.B
169  //   prev_half_redirect := false.B
170  // }
171
172  // when (bpu.io.out(1).valid && if3_fire) {
173  //   when (prev_half_valid && prev_half_taken) {
174  //     if3_redirect := true.B
175  //     if1_npc := prev_half_tgt
176  //     shiftPtr := true.B
177  //     newPtr := if3_histPtr - 1.U
178  //     hist(0) := 1.U
179  //     extHist(newPtr) := 1.U
180  //   }.elsewhen (if3_bp.redirect && !if3_bp.saveHalfRVI) {
181  //     if3_redirect := true.B
182  //     if1_npc := if3_bp.target
183  //     shiftPtr := true.B
184  //     newPtr := Mux(if3_bp.taken || if3_bp.hasNotTakenBrs, if3_histPtr - 1.U, if3_histPtr)
185  //     hist(0) := Mux(if3_bp.taken || if3_bp.hasNotTakenBrs, if3_bp.taken.asUInt, extHist(if3_histPtr))
186  //     extHist(newPtr) := Mux(if3_bp.taken || if3_bp.hasNotTakenBrs, if3_bp.taken.asUInt, extHist(if3_histPtr))
187  //   }.elsewhen (if3_bp.saveHalfRVI) {
188  //     if3_redirect := true.B
189  //     if1_npc := snpc(if3_pc)
190  //     shiftPtr := true.B
191  //     newPtr := Mux(if3_bp.hasNotTakenBrs, if3_histPtr - 1.U, if3_histPtr)
192  //     hist(0) := Mux(if3_bp.hasNotTakenBrs, 0.U, extHist(if3_histPtr))
193  //     extHist(newPtr) := Mux(if3_bp.hasNotTakenBrs, 0.U, extHist(if3_histPtr))
194  //   }.otherwise {
195  //     if3_redirect := false.B
196  //   }
197  // }.otherwise {
198  //   if3_redirect := false.B
199  // }
200
201
202  //********************** IF4 ****************************//
203  val if4_pd = RegEnable(pd.io.out, if3_fire)
204  val if4_valid = RegInit(false.B)
205  val if4_fire = if4_valid && io.fetchPacket.ready
206  val if4_pc = RegEnable(if3_pc, if3_fire)
207  val if4_histPtr = RegEnable(if3_histPtr, if3_fire)
208  if4_ready := (if4_fire || !if4_valid || if4_flush) && GTimer() > 500.U
209  when (if4_flush)     { if4_valid := false.B }
210  .elsewhen (if3_fire) { if4_valid := if3_valid }
211  .elsewhen(if4_fire)  { if4_valid := false.B }
212
213  val if4_bp = Wire(new BranchPrediction)
214  if4_bp := bpu.io.out(2).bits
215
216  val if4_cfi_jal = if4_pd.instrs(if4_bp.jmpIdx)
217  val if4_cfi_jal_tgt = if4_pd.pc(if4_bp.jmpIdx) + Mux(if4_pd.pd(if4_bp.jmpIdx).isRVC,
218    SignExt(Cat(if4_cfi_jal(12), if4_cfi_jal(8), if4_cfi_jal(10, 9), if4_cfi_jal(6), if4_cfi_jal(7), if4_cfi_jal(2), if4_cfi_jal(11), if4_cfi_jal(5, 3), 0.U(1.W)), XLEN),
219    SignExt(Cat(if4_cfi_jal(31), if4_cfi_jal(19, 12), if4_cfi_jal(20), if4_cfi_jal(30, 21), 0.U(1.W)), XLEN))
220  if4_bp.target := Mux(if4_pd.pd(if4_bp.jmpIdx).isJal && if4_bp.taken, if4_cfi_jal_tgt, bpu.io.out(2).bits.target)
221  if4_bp.redirect := bpu.io.out(2).bits.redirect || if4_pd.pd(if4_bp.jmpIdx).isJal && if4_bp.taken && if4_cfi_jal_tgt =/= bpu.io.out(2).bits.target
222
223  if4_prevHalfInstr := 0.U.asTypeOf(new PrevHalfInstr)
224  when (bpu.io.out(2).valid && if4_fire && if4_bp.saveHalfRVI) {
225    if4_prevHalfInstr.valid := true.B
226    if4_prevHalfInstr.taken := if4_bp.taken
227    if4_prevHalfInstr.takenOnBr := if4_bp.takenOnBr
228    if4_prevHalfInstr.fetchpc := if4_pc
229    if4_prevHalfInstr.idx := PopCount(mask(if4_pc)) - 1.U
230    if4_prevHalfInstr.pc := if4_pd.pc(if4_prevHalfInstr.idx)
231    if4_prevHalfInstr.target := if4_bp.target
232    if4_prevHalfInstr.instr := if4_pd.instrs(if4_prevHalfInstr.idx)(15, 0)
233  }
234
235  when (bpu.io.out(2).valid && if4_fire && if4_bp.redirect) {
236    if4_redirect := true.B
237    shiftPtr := true.B
238    newPtr := Mux(if4_bp.takenOnBr || if4_bp.hasNotTakenBrs, if4_histPtr - 1.U, if4_histPtr)
239    hist(0) := Mux(if4_bp.takenOnBr || if4_bp.hasNotTakenBrs, if4_bp.takenOnBr.asUInt, extHist(if4_histPtr))
240    extHist(newPtr) := Mux(if4_bp.takenOnBr || if4_bp.hasNotTakenBrs, if4_bp.takenOnBr.asUInt, extHist(if4_histPtr))
241    when (if4_bp.saveHalfRVI) {
242      if1_npc := snpc(if4_pc)
243    }.otherwise {
244      if1_npc := if4_bp.target
245    }
246  }.elsewhen (bpu.io.out(2).valid && if4_fire/* && !if4_bp.redirect*/) {
247    when (if4_bp.saveHalfRVI && if4_bp.takenOnBr) {
248      if4_redirect := true.B
249      if1_npc := snpc(if4_pc)
250      shiftPtr := true.B
251      newPtr := if4_histPtr - 1.U
252      hist(0) := 1.U
253      extHist(newPtr) := 1.U
254    }.elsewhen (if4_bp.saveHalfRVI && if4_bp.taken) {
255      if4_redirect := true.B
256      if1_npc := snpc(if4_pc)
257      shiftPtr := true.B
258      newPtr := if4_histPtr
259      hist(0) := extHist(if4_histPtr)
260      extHist(newPtr) := extHist(if4_histPtr)
261    }.otherwise {
262      if4_redirect := false.B
263    }
264  }.otherwise {
265    if4_redirect := false.B
266  }
267
268
269
270  // when (bpu.io.out(2).valid && if4_fire && if4_bp.redirect) {
271  //   when (!if4_bp.saveHalfRVI) {
272  //     if4_redirect := true.B
273  //     // if1_npc := if4_bp.target
274  //     if1_npc := Mux(if4_bp.taken, if4_bp.target, snpc(if4_pc))
275
276  //     shiftPtr := true.B
277  //     newPtr := Mux(if4_bp.taken || if4_bp.hasNotTakenBrs, if4_histPtr - 1.U, if4_histPtr)
278  //     hist(0) := Mux(if4_bp.taken || if4_bp.hasNotTakenBrs, if4_bp.taken.asUInt, extHist(if4_histPtr))
279  //     extHist(newPtr) := Mux(if4_bp.taken || if4_bp.hasNotTakenBrs, if4_bp.taken.asUInt, extHist(if4_histPtr))
280
281  //   }.otherwise {
282  //     if4_redirect := true.B
283  //     if1_npc := snpc(if4_pc)
284
285  //     prev_half_valid := true.B
286  //     prev_half_redirect := true.B
287  //     prev_half_fetchpc := if4_pc
288  //     val idx = PopCount(mask(if4_pc)) - 1.U
289  //     prev_half_idx := idx
290  //     prev_half_tgt := if4_bp.target
291  //     prev_half_taken := if4_bp.taken
292  //     prev_half_instr := if4_pd.instrs(idx)(15, 0)
293
294  //     shiftPtr := true.B
295  //     newPtr := Mux(if4_bp.hasNotTakenBrs, if4_histPtr - 1.U, if4_histPtr)
296  //     hist(0) := Mux(if4_bp.hasNotTakenBrs, 0.U, extHist(if4_histPtr))
297  //     extHist(newPtr) := Mux(if4_bp.hasNotTakenBrs, 0.U, extHist(if4_histPtr))
298  //   }
299  // }.otherwise {
300  //   if4_redirect := false.B
301  // }
302
303  when (io.outOfOrderBrInfo.valid && io.outOfOrderBrInfo.bits.isMisPred) {
304    val b = io.outOfOrderBrInfo.bits
305    val oldPtr = b.brInfo.histPtr
306    shiftPtr := true.B
307    when (!b.pd.isBr && !b.brInfo.sawNotTakenBranch) {
308      // If mispredicted cfi is not a branch,
309      // and there wasn't any not taken branch before it,
310      // we should only recover the pointer to an unshifted state
311      newPtr := oldPtr
312    }.otherwise {
313      newPtr := oldPtr - 1.U
314      hist(0) := b.taken
315      extHist(newPtr) := b.taken
316    }
317  }
318
319  when (io.redirect.valid) {
320    if1_npc := io.redirect.bits.target
321  }
322
323  io.icacheReq.valid := if1_valid && if2_ready
324  io.icacheReq.bits.addr := if1_npc
325  io.icacheResp.ready := if3_ready
326  io.icacheFlush := Cat(if3_flush, if2_flush)
327
328  val inOrderBrHist = Wire(Vec(HistoryLength, UInt(1.W)))
329  (0 until HistoryLength).foreach(i => inOrderBrHist(i) := extHist(i.U + io.inOrderBrInfo.bits.brInfo.histPtr))
330  bpu.io.inOrderBrInfo.valid := io.inOrderBrInfo.valid
331  bpu.io.inOrderBrInfo.bits := BranchUpdateInfoWithHist(io.inOrderBrInfo.bits, inOrderBrHist.asUInt)
332  bpu.io.outOfOrderBrInfo.valid := io.outOfOrderBrInfo.valid
333  bpu.io.outOfOrderBrInfo.bits := BranchUpdateInfoWithHist(io.outOfOrderBrInfo.bits, inOrderBrHist.asUInt) // Dont care about hist
334
335  // bpu.io.flush := Cat(if4_flush, if3_flush, if2_flush)
336  bpu.io.flush := VecInit(if2_flush, if3_flush, if4_flush)
337  bpu.io.in.valid := if1_fire
338  bpu.io.in.bits.pc := if1_npc
339  bpu.io.in.bits.hist := hist.asUInt
340  bpu.io.in.bits.inMask := mask(if1_npc)
341  bpu.io.out(0).ready := if2_fire
342  bpu.io.out(1).ready := if3_fire
343  bpu.io.out(2).ready := if4_fire
344  bpu.io.predecode.valid := if4_valid
345  bpu.io.predecode.bits.mask := if4_pd.mask
346  bpu.io.predecode.bits.pd := if4_pd.pd
347  bpu.io.predecode.bits.isFetchpcEqualFirstpc := if4_pc === if4_pd.pc(0)
348  bpu.io.branchInfo.ready := if4_fire
349
350  pd.io.in := io.icacheResp.bits
351  pd.io.prev.valid := if3_hasPrevHalfInstr
352  pd.io.prev.bits := prevHalfInstr.instr
353
354  io.fetchPacket.valid := if4_valid && !io.redirect.valid
355  io.fetchPacket.bits.instrs := if4_pd.instrs
356  io.fetchPacket.bits.mask := if4_pd.mask & (Fill(PredictWidth, !if4_bp.taken) | (Fill(PredictWidth, 1.U(1.W)) >> (~if4_bp.jmpIdx)))
357  io.fetchPacket.bits.pc := if4_pd.pc
358  (0 until PredictWidth).foreach(i => io.fetchPacket.bits.pnpc(i) := if4_pd.pc(i) + Mux(if4_pd.pd(i).isRVC, 2.U, 4.U))
359  when (if4_bp.taken) {
360    io.fetchPacket.bits.pnpc(if4_bp.jmpIdx) := if4_bp.target
361  }
362  io.fetchPacket.bits.brInfo := bpu.io.branchInfo.bits
363  (0 until PredictWidth).foreach(i => io.fetchPacket.bits.brInfo(i).histPtr := if4_histPtr)
364  io.fetchPacket.bits.pd := if4_pd.pd
365
366  // debug info
367  XSDebug(RegNext(reset.asBool) && !reset.asBool, "Reseting...\n")
368  XSDebug(io.icacheFlush(0).asBool, "Flush icache stage2...\n")
369  XSDebug(io.icacheFlush(1).asBool, "Flush icache stage3...\n")
370  XSDebug(io.redirect.valid, "Redirect from backend! isExcp=%d isMisPred=%d isReplay=%d pc=%x\n",
371    io.redirect.bits.isException, io.redirect.bits.isMisPred, io.redirect.bits.isReplay, io.redirect.bits.pc)
372  XSDebug(io.redirect.valid, p"Redirect from backend! target=${Hexadecimal(io.redirect.bits.target)} brTag=${io.redirect.bits.brTag}\n")
373
374  XSDebug("[IF1] v=%d     fire=%d            flush=%d pc=%x ptr=%d mask=%b\n", if1_valid, if1_fire, if1_flush, if1_npc, ptr, mask(if1_npc))
375  XSDebug("[IF2] v=%d r=%d fire=%d redirect=%d flush=%d pc=%x ptr=%d snpc=%x\n", if2_valid, if2_ready, if2_fire, if2_redirect, if2_flush, if2_pc, if2_histPtr, if2_snpc)
376  XSDebug("[IF3] v=%d r=%d fire=%d redirect=%d flush=%d pc=%x ptr=%d\n", if3_valid, if3_ready, if3_fire, if3_redirect, if3_flush, if3_pc, if3_histPtr)
377  XSDebug("[IF4] v=%d r=%d fire=%d redirect=%d flush=%d pc=%x ptr=%d\n", if4_valid, if4_ready, if4_fire, if4_redirect, if4_flush, if4_pc, if4_histPtr)
378
379  XSDebug("[IF1][icacheReq] v=%d r=%d addr=%x\n", io.icacheReq.valid, io.icacheReq.ready, io.icacheReq.bits.addr)
380  XSDebug("[IF1][ghr] headPtr=%d shiftPtr=%d newPtr=%d ptr=%d\n", headPtr, shiftPtr, newPtr, ptr)
381  XSDebug("[IF1][ghr] hist=%b\n", hist.asUInt)
382  XSDebug("[IF1][ghr] extHist=%b\n\n", extHist.asUInt)
383
384  XSDebug("[IF2][bp] redirect=%d taken=%d jmpIdx=%d hasNTBrs=%d target=%x saveHalfRVI=%d\n\n", if2_bp.redirect, if2_bp.taken, if2_bp.jmpIdx, if2_bp.hasNotTakenBrs, if2_bp.target, if2_bp.saveHalfRVI)
385
386  XSDebug("[IF3][icacheResp] v=%d r=%d pc=%x mask=%b\n", io.icacheResp.valid, io.icacheResp.ready, io.icacheResp.bits.pc, io.icacheResp.bits.mask)
387  XSDebug("[IF3][bp] redirect=%d taken=%d jmpIdx=%d hasNTBrs=%d target=%x saveHalfRVI=%d\n", if3_bp.redirect, if3_bp.taken, if3_bp.jmpIdx, if3_bp.hasNotTakenBrs, if3_bp.target, if3_bp.saveHalfRVI)
388  // XSDebug("[IF3][prevHalfInstr] v=%d redirect=%d fetchpc=%x idx=%d tgt=%x taken=%d instr=%x\n\n",
389  //   prev_half_valid, prev_half_redirect, prev_half_fetchpc, prev_half_idx, prev_half_tgt, prev_half_taken, prev_half_instr)
390  XSDebug("[IF3][    prevHalfInstr] v=%d taken=%d fetchpc=%x idx=%d pc=%x tgt=%x instr=%x\n",
391    prevHalfInstr.valid, prevHalfInstr.taken, prevHalfInstr.fetchpc, prevHalfInstr.idx, prevHalfInstr.pc, prevHalfInstr.target, prevHalfInstr.instr)
392  XSDebug("[IF3][if3_prevHalfInstr] v=%d taken=%d fetchpc=%x idx=%d pc=%x tgt=%x instr=%x\n\n",
393    if3_prevHalfInstr.valid, if3_prevHalfInstr.taken, if3_prevHalfInstr.fetchpc, if3_prevHalfInstr.idx, if3_prevHalfInstr.pc, if3_prevHalfInstr.target, if3_prevHalfInstr.instr)
394
395
396  XSDebug("[IF4][predecode] mask=%b\n", if4_pd.mask)
397  XSDebug("[IF4][bp] redirect=%d taken=%d jmpIdx=%d hasNTBrs=%d target=%x saveHalfRVI=%d\n", if4_bp.redirect, if4_bp.taken, if4_bp.jmpIdx, if4_bp.hasNotTakenBrs, if4_bp.target, if4_bp.saveHalfRVI)
398  XSDebug(if4_pd.pd(if4_bp.jmpIdx).isJal && if4_bp.taken, "[IF4] cfi is jal!  instr=%x target=%x\n", if4_cfi_jal, if4_cfi_jal_tgt)
399  XSDebug("[IF4][if4_prevHalfInstr] v=%d taken=%d fetchpc=%x idx=%d pc=%x tgt=%x instr=%x\n",
400    if4_prevHalfInstr.valid, if4_prevHalfInstr.taken, if4_prevHalfInstr.fetchpc, if4_prevHalfInstr.idx, if4_prevHalfInstr.pc, if4_prevHalfInstr.target, if4_prevHalfInstr.instr)
401  XSDebug(io.fetchPacket.fire(), "[IF4][fetchPacket] v=%d r=%d mask=%b\n", io.fetchPacket.valid, io.fetchPacket.ready, io.fetchPacket.bits.mask)
402  for (i <- 0 until PredictWidth) {
403    XSDebug(io.fetchPacket.fire(), "[IF4][fetchPacket] %b %x pc=%x pnpc=%x pd: rvc=%d brType=%b call=%d ret=%d\n",
404      io.fetchPacket.bits.mask(i),
405      io.fetchPacket.bits.instrs(i),
406      io.fetchPacket.bits.pc(i),
407      io.fetchPacket.bits.pnpc(i),
408      io.fetchPacket.bits.pd(i).isRVC,
409      io.fetchPacket.bits.pd(i).brType,
410      io.fetchPacket.bits.pd(i).isCall,
411      io.fetchPacket.bits.pd(i).isRet
412    )
413  }
414}