xref: /XiangShan/src/main/scala/xiangshan/backend/rename/RenameTable.scala (revision de8bd1d0fba1fb5a86000bb0348ed5524a93658d)
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.rename
18
19import org.chipsalliance.cde.config.Parameters
20import chisel3._
21import chisel3.util._
22import utility.HasCircularQueuePtrHelper
23import utility.ParallelPriorityMux
24import utility.GatedValidRegNext
25import utils.XSError
26import xiangshan._
27
28abstract class RegType
29case object Reg_I extends RegType
30case object Reg_F extends RegType
31case object Reg_V extends RegType
32case object Reg_V0 extends RegType
33case object Reg_Vl extends RegType
34
35class RatReadPort(implicit p: Parameters) extends XSBundle {
36  val hold = Input(Bool())
37  val addr = Input(UInt(6.W))
38  val data = Output(UInt(PhyRegIdxWidth.W))
39}
40
41class RatWritePort(implicit p: Parameters) extends XSBundle {
42  val wen = Bool()
43  val addr = UInt(6.W)
44  val data = UInt(PhyRegIdxWidth.W)
45}
46
47class RenameTable(reg_t: RegType)(implicit p: Parameters) extends XSModule with HasCircularQueuePtrHelper {
48
49  // params alias
50  private val numVecRegSrc = backendParams.numVecRegSrc
51  private val numVecRatPorts = numVecRegSrc
52
53  val readPortsNum = reg_t match {
54    case Reg_I => 2
55    case Reg_F => 3
56    case Reg_V => numVecRatPorts // +1 ldest
57    case Reg_V0 => 1
58    case Reg_Vl => 1
59  }
60  val rdataNums = reg_t match {
61    case Reg_I => 32
62    case Reg_F => 32
63    case Reg_V => 31 // no v0
64    case Reg_V0 => 1 // v0
65    case Reg_Vl => 1 // vl
66  }
67  val io = IO(new Bundle {
68    val redirect = Input(Bool())
69    val readPorts = Vec(readPortsNum * RenameWidth, new RatReadPort)
70    val specWritePorts = Vec(RabCommitWidth, Input(new RatWritePort))
71    val archWritePorts = Vec(RabCommitWidth, Input(new RatWritePort))
72    val old_pdest = Vec(RabCommitWidth, Output(UInt(PhyRegIdxWidth.W)))
73    val need_free = Vec(RabCommitWidth, Output(Bool()))
74    val snpt = Input(new SnapshotPort)
75    val diffWritePorts = if (backendParams.debugEn) Some(Vec(RabCommitWidth * MaxUopSize, Input(new RatWritePort))) else None
76    val debug_rdata = if (backendParams.debugEn) Some(Vec(rdataNums, Output(UInt(PhyRegIdxWidth.W)))) else None
77    val diff_rdata = if (backendParams.debugEn) Some(Vec(rdataNums, Output(UInt(PhyRegIdxWidth.W)))) else None
78    val debug_v0 = if (backendParams.debugEn) reg_t match {
79      case Reg_V0 => Some(Output(UInt(PhyRegIdxWidth.W)))
80      case _ => None
81    } else None
82    val diff_v0 = if (backendParams.debugEn) reg_t match {
83      case Reg_V0 => Some(Output(UInt(PhyRegIdxWidth.W)))
84      case _ => None
85    } else None
86    val debug_vl = if (backendParams.debugEn) reg_t match {
87      case Reg_Vl => Some(Output(UInt(PhyRegIdxWidth.W)))
88      case _ => None
89    } else None
90    val diff_vl = if (backendParams.debugEn) reg_t match {
91      case Reg_Vl => Some(Output(UInt(PhyRegIdxWidth.W)))
92      case _ => None
93    } else None
94  })
95
96  // speculative rename table
97  val rename_table_init = reg_t match {
98    case Reg_I => VecInit.fill    (IntLogicRegs)(0.U(PhyRegIdxWidth.W))
99    case Reg_F => VecInit.tabulate(FpLogicRegs)(_.U(PhyRegIdxWidth.W))
100    case Reg_V => VecInit.tabulate(VecLogicRegs)(_.U(PhyRegIdxWidth.W))
101//    case Reg_V0 => VecInit.tabulate(V0LogicRegs)(_.U(PhyRegIdxWidth.W))
102//    case Reg_Vl => VecInit.tabulate(VlLogicRegs)(_.U(PhyRegIdxWidth.W))
103    case Reg_V0 => VecInit.tabulate(2)(_.U(PhyRegIdxWidth.W))
104    case Reg_Vl => VecInit.tabulate(1)(_.U(PhyRegIdxWidth.W))
105  }
106  val spec_table = RegInit(rename_table_init)
107  val spec_table_next = WireInit(spec_table)
108  // arch state rename table
109  val arch_table = RegInit(rename_table_init)
110  val arch_table_next = WireDefault(arch_table)
111  // old_pdest
112  val old_pdest = RegInit(VecInit.fill(RabCommitWidth)(0.U(PhyRegIdxWidth.W)))
113  val need_free = RegInit(VecInit.fill(RabCommitWidth)(false.B))
114
115  // For better timing, we optimize reading and writing to RenameTable as follows:
116  // (1) Writing at T0 will be actually processed at T1.
117  // (2) Reading is synchronous now.
118  // (3) RAddr at T0 will be used to access the table and get data at T0.
119  // (4) WData at T0 is bypassed to RData at T1.
120  val t1_redirect = GatedValidRegNext(io.redirect, false.B)
121  val t1_raddr = io.readPorts.map(p => RegEnable(p.addr, !p.hold))
122  val t1_rdata_use_t1_raddr = VecInit(t1_raddr.map(spec_table(_)))
123  val t1_wSpec = RegNext(Mux(io.redirect, 0.U.asTypeOf(io.specWritePorts), io.specWritePorts))
124
125  val t1_snpt = RegNext(io.snpt, 0.U.asTypeOf(io.snpt))
126
127  val snapshots = SnapshotGenerator(spec_table, t1_snpt.snptEnq, t1_snpt.snptDeq, t1_redirect, t1_snpt.flushVec)
128
129  // WRITE: when instruction commits or walking
130  val t1_wSpec_addr = t1_wSpec.map(w => Mux(w.wen, UIntToOH(w.addr), 0.U))
131  for ((next, i) <- spec_table_next.zipWithIndex) {
132    val matchVec = t1_wSpec_addr.map(w => w(i))
133    val wMatch = ParallelPriorityMux(matchVec.reverse, t1_wSpec.map(_.data).reverse)
134    // When there's a flush, we use arch_table to update spec_table.
135    next := Mux(
136      t1_redirect,
137      Mux(t1_snpt.useSnpt, snapshots(t1_snpt.snptSelect)(i), arch_table(i)),
138      Mux(VecInit(matchVec).asUInt.orR, wMatch, spec_table(i))
139    )
140  }
141  spec_table := spec_table_next
142
143  // READ: decode-rename stage
144  for ((r, i) <- io.readPorts.zipWithIndex) {
145    val t0_bypass = io.specWritePorts.map(w => w.wen && Mux(r.hold, w.addr === t1_raddr(i), w.addr === r.addr))
146    val t1_bypass = RegNext(Mux(io.redirect, 0.U.asTypeOf(VecInit(t0_bypass)), VecInit(t0_bypass)))
147    val bypass_data = ParallelPriorityMux(t1_bypass.reverse, t1_wSpec.map(_.data).reverse)
148    r.data := Mux(t1_bypass.asUInt.orR, bypass_data, t1_rdata_use_t1_raddr(i))
149  }
150
151  for ((w, i) <- io.archWritePorts.zipWithIndex) {
152    when (w.wen) {
153      arch_table_next(w.addr) := w.data
154    }
155    val arch_mask = VecInit.fill(PhyRegIdxWidth)(w.wen).asUInt
156    old_pdest(i) :=
157      MuxCase(arch_table(w.addr) & arch_mask,
158              io.archWritePorts.take(i).reverse.map(x => (x.wen && x.addr === w.addr, x.data & arch_mask)))
159  }
160  arch_table := arch_table_next
161
162  for (((old, free), i) <- (old_pdest zip need_free).zipWithIndex) {
163    val hasDuplicate = old_pdest.take(i).map(_ === old)
164    val blockedByDup = if (i == 0) false.B else VecInit(hasDuplicate).asUInt.orR
165    free := VecInit(arch_table.map(_ =/= old)).asUInt.andR && !blockedByDup
166  }
167
168  io.old_pdest := old_pdest
169  io.need_free := need_free
170  io.debug_rdata.foreach(_ := arch_table.take(rdataNums))
171  io.debug_v0.foreach(_ := arch_table(0))
172  io.debug_vl.foreach(_ := arch_table(0))
173  if (env.EnableDifftest || env.AlwaysBasicDiff) {
174    val difftest_table = RegInit(rename_table_init)
175    val difftest_table_next = WireDefault(difftest_table)
176
177    for (w <- io.diffWritePorts.get) {
178      when(w.wen) {
179        difftest_table_next(w.addr) := w.data
180      }
181    }
182    difftest_table := difftest_table_next
183
184    io.diff_rdata.foreach(_ := difftest_table.take(rdataNums))
185    io.diff_v0.foreach(_ := difftest_table(0))
186    io.diff_vl.foreach(_ := difftest_table(0))
187  }
188  else {
189    io.diff_rdata.foreach(_ := 0.U.asTypeOf(io.debug_rdata.get))
190    io.diff_v0.foreach(_ := 0.U)
191    io.diff_vl.foreach(_ := 0.U)
192  }
193}
194
195class RenameTableWrapper(implicit p: Parameters) extends XSModule {
196
197  // params alias
198  private val numVecRegSrc = backendParams.numVecRegSrc
199  private val numVecRatPorts = numVecRegSrc
200
201  val io = IO(new Bundle() {
202    val redirect = Input(Bool())
203    val rabCommits = Input(new RabCommitIO)
204    val diffCommits = if (backendParams.debugEn) Some(Input(new DiffCommitIO)) else None
205    val intReadPorts = Vec(RenameWidth, Vec(2, new RatReadPort))
206    val intRenamePorts = Vec(RenameWidth, Input(new RatWritePort))
207    val fpReadPorts = Vec(RenameWidth, Vec(3, new RatReadPort))
208    val fpRenamePorts = Vec(RenameWidth, Input(new RatWritePort))
209    val vecReadPorts = Vec(RenameWidth, Vec(numVecRatPorts, new RatReadPort))
210    val vecRenamePorts = Vec(RenameWidth, Input(new RatWritePort))
211    val v0ReadPorts = Vec(RenameWidth, new RatReadPort)
212    val v0RenamePorts = Vec(RenameWidth, Input(new RatWritePort))
213    val vlReadPorts = Vec(RenameWidth, new RatReadPort)
214    val vlRenamePorts = Vec(RenameWidth, Input(new RatWritePort))
215
216    val int_old_pdest = Vec(RabCommitWidth, Output(UInt(PhyRegIdxWidth.W)))
217    val fp_old_pdest = Vec(RabCommitWidth, Output(UInt(PhyRegIdxWidth.W)))
218    val vec_old_pdest = Vec(RabCommitWidth, Output(UInt(PhyRegIdxWidth.W)))
219    val v0_old_pdest = Vec(RabCommitWidth, Output(UInt(PhyRegIdxWidth.W)))
220    val vl_old_pdest = Vec(RabCommitWidth, Output(UInt(PhyRegIdxWidth.W)))
221    val int_need_free = Vec(RabCommitWidth, Output(Bool()))
222    val snpt = Input(new SnapshotPort)
223
224    // for debug printing
225    val debug_int_rat     = if (backendParams.debugEn) Some(Vec(32, Output(UInt(PhyRegIdxWidth.W)))) else None
226    val debug_fp_rat      = if (backendParams.debugEn) Some(Vec(32, Output(UInt(PhyRegIdxWidth.W)))) else None
227    val debug_vec_rat     = if (backendParams.debugEn) Some(Vec(31, Output(UInt(PhyRegIdxWidth.W)))) else None
228    val debug_v0_rat      = if (backendParams.debugEn) Some(Output(UInt(PhyRegIdxWidth.W))) else None
229    val debug_vl_rat      = if (backendParams.debugEn) Some(Output(UInt(PhyRegIdxWidth.W))) else None
230
231    val diff_int_rat     = if (backendParams.debugEn) Some(Vec(32, Output(UInt(PhyRegIdxWidth.W)))) else None
232    val diff_fp_rat      = if (backendParams.debugEn) Some(Vec(32, Output(UInt(PhyRegIdxWidth.W)))) else None
233    val diff_vec_rat     = if (backendParams.debugEn) Some(Vec(31, Output(UInt(PhyRegIdxWidth.W)))) else None
234    val diff_v0_rat      = if (backendParams.debugEn) Some(Output(UInt(PhyRegIdxWidth.W))) else None
235    val diff_vl_rat      = if (backendParams.debugEn) Some(Output(UInt(PhyRegIdxWidth.W))) else None
236  })
237
238  val intRat = Module(new RenameTable(Reg_I))
239  val fpRat  = Module(new RenameTable(Reg_F))
240  val vecRat = Module(new RenameTable(Reg_V))
241  val v0Rat  = Module(new RenameTable(Reg_V0))
242  val vlRat  = Module(new RenameTable(Reg_Vl))
243
244  io.debug_int_rat .foreach(_ := intRat.io.debug_rdata.get)
245  io.diff_int_rat  .foreach(_ := intRat.io.diff_rdata.get)
246  intRat.io.readPorts <> io.intReadPorts.flatten
247  intRat.io.redirect := io.redirect
248  intRat.io.snpt := io.snpt
249  io.int_old_pdest := intRat.io.old_pdest
250  io.int_need_free := intRat.io.need_free
251  val intDestValid = io.rabCommits.info.map(_.rfWen)
252  for ((arch, i) <- intRat.io.archWritePorts.zipWithIndex) {
253    arch.wen  := io.rabCommits.isCommit && io.rabCommits.commitValid(i) && intDestValid(i)
254    arch.addr := io.rabCommits.info(i).ldest
255    arch.data := io.rabCommits.info(i).pdest
256    XSError(arch.wen && arch.addr === 0.U && arch.data =/= 0.U, "pdest for $0 should be 0\n")
257  }
258  for ((spec, i) <- intRat.io.specWritePorts.zipWithIndex) {
259    spec.wen  := io.rabCommits.isWalk && io.rabCommits.walkValid(i) && intDestValid(i)
260    spec.addr := io.rabCommits.info(i).ldest
261    spec.data := io.rabCommits.info(i).pdest
262    XSError(spec.wen && spec.addr === 0.U && spec.data =/= 0.U, "pdest for $0 should be 0\n")
263  }
264  for ((spec, rename) <- intRat.io.specWritePorts.zip(io.intRenamePorts)) {
265    when (rename.wen) {
266      spec.wen  := true.B
267      spec.addr := rename.addr
268      spec.data := rename.data
269    }
270  }
271  if (backendParams.debugEn) {
272    for ((diff, i) <- intRat.io.diffWritePorts.get.zipWithIndex) {
273      diff.wen := io.diffCommits.get.isCommit && io.diffCommits.get.commitValid(i) && io.diffCommits.get.info(i).rfWen
274      diff.addr := io.diffCommits.get.info(i).ldest
275      diff.data := io.diffCommits.get.info(i).pdest
276    }
277  }
278
279  // debug read ports for difftest
280  io.debug_fp_rat.foreach(_ := fpRat.io.debug_rdata.get)
281  io.diff_fp_rat .foreach(_ := fpRat.io.diff_rdata.get)
282  fpRat.io.readPorts <> io.fpReadPorts.flatten
283  fpRat.io.redirect := io.redirect
284  fpRat.io.snpt := io.snpt
285  io.fp_old_pdest := fpRat.io.old_pdest
286
287  for ((arch, i) <- fpRat.io.archWritePorts.zipWithIndex) {
288    arch.wen  := io.rabCommits.isCommit && io.rabCommits.commitValid(i) && io.rabCommits.info(i).fpWen
289    arch.addr := io.rabCommits.info(i).ldest
290    arch.data := io.rabCommits.info(i).pdest
291  }
292  for ((spec, i) <- fpRat.io.specWritePorts.zipWithIndex) {
293    spec.wen  := io.rabCommits.isWalk && io.rabCommits.walkValid(i) && io.rabCommits.info(i).fpWen
294    spec.addr := io.rabCommits.info(i).ldest
295    spec.data := io.rabCommits.info(i).pdest
296  }
297  for ((spec, rename) <- fpRat.io.specWritePorts.zip(io.fpRenamePorts)) {
298    when (rename.wen) {
299      spec.wen  := true.B
300      spec.addr := rename.addr
301      spec.data := rename.data
302    }
303  }
304  if (backendParams.debugEn) {
305    for ((diff, i) <- fpRat.io.diffWritePorts.get.zipWithIndex) {
306      diff.wen := io.diffCommits.get.isCommit && io.diffCommits.get.commitValid(i) && io.diffCommits.get.info(i).fpWen
307      diff.addr := io.diffCommits.get.info(i).ldest
308      diff.data := io.diffCommits.get.info(i).pdest
309    }
310  }
311
312  // debug read ports for difftest
313  io.debug_vec_rat    .foreach(_ := vecRat.io.debug_rdata.get)
314  io.diff_vec_rat     .foreach(_ := vecRat.io.diff_rdata.get)
315  vecRat.io.readPorts <> io.vecReadPorts.flatten
316  vecRat.io.redirect := io.redirect
317  vecRat.io.snpt := io.snpt
318  io.vec_old_pdest := vecRat.io.old_pdest
319
320  //TODO: RM the donTouch
321  if(backendParams.debugEn) {
322    dontTouch(vecRat.io)
323  }
324  for ((arch, i) <- vecRat.io.archWritePorts.zipWithIndex) {
325    arch.wen  := io.rabCommits.isCommit && io.rabCommits.commitValid(i) && io.rabCommits.info(i).vecWen
326    arch.addr := io.rabCommits.info(i).ldest
327    arch.data := io.rabCommits.info(i).pdest
328  }
329  for ((spec, i) <- vecRat.io.specWritePorts.zipWithIndex) {
330    spec.wen  := io.rabCommits.isWalk && io.rabCommits.walkValid(i) && io.rabCommits.info(i).vecWen
331    spec.addr := io.rabCommits.info(i).ldest
332    spec.data := io.rabCommits.info(i).pdest
333  }
334  for ((spec, rename) <- vecRat.io.specWritePorts.zip(io.vecRenamePorts)) {
335    when (rename.wen) {
336      spec.wen  := true.B
337      spec.addr := rename.addr
338      spec.data := rename.data
339    }
340  }
341  if (backendParams.debugEn) {
342    for ((diff, i) <- vecRat.io.diffWritePorts.get.zipWithIndex) {
343      diff.wen := io.diffCommits.get.isCommit && io.diffCommits.get.commitValid(i) && io.diffCommits.get.info(i).vecWen
344      diff.addr := io.diffCommits.get.info(i).ldest
345      diff.data := io.diffCommits.get.info(i).pdest
346    }
347  }
348
349  // debug read ports for difftest
350  io.debug_v0_rat.foreach(_ := v0Rat.io.debug_rdata.get)
351  io.diff_v0_rat.foreach(_ := v0Rat.io.diff_rdata.get)
352  v0Rat.io.readPorts <> io.v0ReadPorts
353  v0Rat.io.redirect := io.redirect
354  v0Rat.io.snpt := io.snpt
355  io.v0_old_pdest := v0Rat.io.old_pdest
356
357  if (backendParams.debugEn) {
358    dontTouch(v0Rat.io)
359  }
360  for ((arch, i) <- v0Rat.io.archWritePorts.zipWithIndex) {
361    arch.wen := io.rabCommits.isCommit && io.rabCommits.commitValid(i) && io.rabCommits.info(i).v0Wen
362    arch.addr := io.rabCommits.info(i).ldest
363    arch.data := io.rabCommits.info(i).pdest
364  }
365  for ((spec, i) <- v0Rat.io.specWritePorts.zipWithIndex) {
366    spec.wen := io.rabCommits.isWalk && io.rabCommits.walkValid(i) && io.rabCommits.info(i).v0Wen
367    spec.addr := io.rabCommits.info(i).ldest
368    spec.data := io.rabCommits.info(i).pdest
369  }
370  for ((spec, rename) <- v0Rat.io.specWritePorts.zip(io.v0RenamePorts)) {
371    when(rename.wen) {
372      spec.wen := true.B
373      spec.addr := rename.addr
374      spec.data := rename.data
375    }
376  }
377  if (backendParams.debugEn) {
378    for ((diff, i) <- v0Rat.io.diffWritePorts.get.zipWithIndex) {
379      diff.wen := io.diffCommits.get.isCommit && io.diffCommits.get.commitValid(i) && io.diffCommits.get.info(i).v0Wen
380      diff.addr := io.diffCommits.get.info(i).ldest
381      diff.data := io.diffCommits.get.info(i).pdest
382    }
383  }
384
385  // debug read ports for difftest
386  io.debug_vl_rat.foreach(_ := vlRat.io.debug_rdata.get)
387  io.diff_vl_rat.foreach(_ := vlRat.io.diff_rdata.get)
388  vlRat.io.readPorts <> io.vlReadPorts
389  vlRat.io.redirect := io.redirect
390  vlRat.io.snpt := io.snpt
391  io.vl_old_pdest := vlRat.io.old_pdest
392
393  if (backendParams.debugEn) {
394    dontTouch(vlRat.io)
395  }
396  for ((arch, i) <- vlRat.io.archWritePorts.zipWithIndex) {
397    arch.wen := io.rabCommits.isCommit && io.rabCommits.commitValid(i) && io.rabCommits.info(i).vlWen
398    arch.addr := io.rabCommits.info(i).ldest
399    arch.data := io.rabCommits.info(i).pdest
400  }
401  for ((spec, i) <- vlRat.io.specWritePorts.zipWithIndex) {
402    spec.wen := io.rabCommits.isWalk && io.rabCommits.walkValid(i) && io.rabCommits.info(i).vlWen
403    spec.addr := io.rabCommits.info(i).ldest
404    spec.data := io.rabCommits.info(i).pdest
405  }
406  for ((spec, rename) <- vlRat.io.specWritePorts.zip(io.vlRenamePorts)) {
407    when(rename.wen) {
408      spec.wen := true.B
409      spec.addr := rename.addr
410      spec.data := rename.data
411    }
412  }
413  if (backendParams.debugEn) {
414    for ((diff, i) <- vlRat.io.diffWritePorts.get.zipWithIndex) {
415      diff.wen := io.diffCommits.get.isCommit && io.diffCommits.get.commitValid(i) && io.diffCommits.get.info(i).vlWen
416      diff.addr := io.diffCommits.get.info(i).ldest
417      diff.data := io.diffCommits.get.info(i).pdest
418    }
419  }
420}
421