xref: /XiangShan/src/main/scala/xiangshan/backend/fu/SRT4Divider.scala (revision e3da8bad334fc71ba0d72f0607e2e93245ddaece)
1/***************************************************************************************
2* Copyright (c) 2024 Beijing Institute of Open Source Chip (BOSC)
3* Copyright (c) 2020-2024 Institute of Computing Technology, Chinese Academy of Sciences
4* Copyright (c) 2020-2021 Peng Cheng Laboratory
5*
6* XiangShan is licensed under Mulan PSL v2.
7* You can use this software according to the terms and conditions of the Mulan PSL v2.
8* You may obtain a copy of Mulan PSL v2 at:
9*          http://license.coscl.org.cn/MulanPSL2
10*
11* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
12* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
13* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
14*
15* See the Mulan PSL v2 for more details.
16***************************************************************************************/
17
18// The "SRT4DividerDataModule" in this file is a scala rewrite of SRT4 divider by Yifei He, see
19// https://github.com/OpenXiangShan/XS-Verilog-Library/tree/main/int_div_radix_4_v1
20// Email of original author: [email protected]
21
22package xiangshan.backend.fu
23
24import org.chipsalliance.cde.config.Parameters
25import chisel3._
26import chisel3.util._
27import utility.SignExt
28import xiangshan.backend.fu.util.CSA3_2
29
30/** A Radix-4 SRT Integer Divider
31  *
32  * 2 ~ (5 + (len+3)/2) cycles are needed for each division.
33  */
34class SRT4DividerDataModule(len: Int) extends Module {
35  val io = IO(new Bundle() {
36    val src = Vec(2, Input(UInt(len.W)))
37    val valid, sign, kill_w, kill_r, isHi, isW = Input(Bool())
38    val in_ready = Output(Bool())
39    val out_valid = Output(Bool())
40    val out_data = Output(UInt(len.W))
41    val out_ready = Input(Bool())
42  })
43
44  // consts
45  val lzc_width = log2Up(len)
46  val itn_len = 1 + len + 2 + 1
47  require(lzc_width == 6)
48
49  val (a, d, sign, valid, kill_w, kill_r, isHi, isW) =
50    (io.src(0), io.src(1), io.sign, io.valid, io.kill_w, io.kill_r, io.isHi, io.isW)
51  val in_fire = valid && io.in_ready
52  val out_fire = io.out_ready && io.out_valid
53  val newReq = in_fire
54  val startHandShake = io.in_ready && valid
55  val s_idle :: s_pre_0 :: s_pre_1 :: s_iter :: s_post_0 :: s_post_1 :: s_finish :: Nil = Enum(7)
56
57  val state = RegInit(UIntToOH(s_idle, 7))
58
59  val quot_neg_2 :: quot_neg_1 :: quot_0 :: quot_pos_1 :: quot_pos_2 :: Nil = Enum(5)
60
61  val finished = state(s_finish)
62
63  // reused wire declarations
64  val aIsZero = Wire(Bool())
65  val dIsZero = Wire(Bool())
66  val aTooSmall = Wire(Bool()) // this is output of reg!
67  val noIter = Wire(Bool()) // this is output of reg!
68  val finalIter = Wire(Bool())
69  val aLZC = Wire(UInt((lzc_width + 1).W))
70  val dLZC = Wire(UInt((lzc_width + 1).W))
71  val aNormAbs = Wire(UInt((len + 1).W))
72  val dNormAbs = Wire(UInt((len + 1).W))
73  val aInverter = Wire(UInt(len.W)) // results of global inverter
74  val dInverter = Wire(UInt(len.W))
75
76  val rPreShifted = Wire(UInt((len + 1).W))
77
78  val quotIter = Wire(UInt(len.W))
79  val quotM1Iter = Wire(UInt(len.W))
80  val qIterEnd = Wire(UInt(5.W))
81
82  val rNext = Wire(UInt(itn_len.W))
83  val rNextPd = Wire(UInt(itn_len.W)) // non-redundant remainder plus d, 68, 67
84  //reused ctrl regs
85
86  //reused other regs
87  val aNormAbsReg = RegEnable(aNormAbs, startHandShake | state(s_pre_0) | state(s_post_0)) // reg for normalized a & d and rem & rem+d
88  val dNormAbsReg = RegEnable(dNormAbs, startHandShake | state(s_pre_0) | state(s_post_0))
89  val quotIterReg = RegEnable(quotIter, state(s_pre_1) | state(s_iter) | state(s_post_0))
90  val quotM1IterReg = RegEnable(quotM1Iter, state(s_pre_1) | state(s_iter) | state(s_post_0))
91
92  when(kill_r) {
93    state := UIntToOH(s_idle, 7)
94  } .elsewhen(state(s_idle) && in_fire && !kill_w) {
95    state := UIntToOH(s_pre_0, 7)
96  } .elsewhen(state(s_pre_0)) { // leading zero detection
97    state := UIntToOH(s_pre_1, 7)
98  } .elsewhen(state(s_pre_1)) { // shift a/b
99    state := Mux(dIsZero | aTooSmall | noIter, UIntToOH(s_post_0, 7), UIntToOH(s_iter, 7))
100  } .elsewhen(state(s_iter)) { // (ws[j+1], wc[j+1]) = 4(ws[j],wc[j]) - q(j+1)*d
101    state := Mux(finalIter, UIntToOH(s_post_0, 7), UIntToOH(s_iter, 7))
102  } .elsewhen(state(s_post_0)) { // if rem < 0, rem = rem + d
103    state := UIntToOH(s_post_1, 7)
104  } .elsewhen(state(s_post_1)) {
105    state := UIntToOH(s_finish, 7)
106  } .elsewhen(state(s_finish) && out_fire) {
107    state := UIntToOH(s_idle, 7)
108  } .otherwise {
109    state := state
110  }
111
112  // First cycle:
113  // State is idle, we gain absolute value of a and b, using global inverter
114
115  io.in_ready := state(s_idle)
116
117  aInverter := -Mux(state(s_idle), a, quotIterReg) // 64, 0
118  dInverter := -Mux(state(s_idle), d, quotM1IterReg) // 64, 0
119
120  val aSign = io.sign && a(len - 1) // 1
121  val dSign = io.sign && d(len - 1)
122
123  val aAbs = Mux(aSign, aInverter, a) // 64, 0
124  val dAbs = Mux(dSign, dInverter, d)
125  val aNorm = (aNormAbsReg(len - 1, 0) << aLZC(lzc_width - 1, 0))(len - 1, 0) // 64, 65
126  val dNorm = (dNormAbsReg(len - 1, 0) << dLZC(lzc_width - 1, 0))(len - 1, 0)
127
128  aNormAbs := Mux1H(Seq(
129    state(s_idle) -> Cat(0.U(1.W), aAbs), // 65, 0
130    state(s_pre_0) -> Cat(0.U(1.W), aNorm), // 65, 0
131    state(s_post_0) -> rNext(len + 3, 3) // remainder 65, 64. highest is sign bit
132  ))
133  dNormAbs := Mux1H(Seq(
134    state(s_idle) -> Cat(0.U(1.W), dAbs),
135    state(s_pre_0) -> Cat(0.U(1.W), dNorm),
136    state(s_post_0) -> rNextPd(len + 3, 3)
137    ))
138
139  // Second cycle, state is pre_0
140  // calculate lzc and move div* and lzc diff check if no_iter_needed
141
142  aLZC := PriorityEncoder(aNormAbsReg(len - 1, 0).asBools.reverse)
143  dLZC := PriorityEncoder(dNormAbsReg(len - 1, 0).asBools.reverse)
144  val aLZCReg = RegEnable(aLZC, state(s_pre_0)) // 7, 0
145  val dLZCReg = RegEnable(dLZC, state(s_pre_0))
146
147
148
149  val lzcWireDiff = Cat(0.U(1.W), dLZC(lzc_width - 1, 0)) - Cat(0.U(1.W), aLZC(lzc_width - 1, 0)) // 7, 0
150  val lzcRegDiff = Cat(0.U(1.W), dLZCReg(lzc_width - 1, 0)) - Cat(0.U(1.W), aLZCReg(lzc_width - 1, 0))
151  val lzcDiff = Mux(state(s_pre_0), lzcWireDiff, lzcRegDiff)
152  aIsZero := aLZC(lzc_width) // this is state pre_0
153  dIsZero := dLZCReg(lzc_width) // this is pre_1 and all stages after
154  val dIsOne = dLZC(lzc_width - 1, 0).andR // this is pre_0
155  val noIterReg = RegEnable(dIsOne & aNormAbsReg(len - 1), state(s_pre_0)) // This means dividend has lzc 0 so iter is 17
156  noIter := noIterReg
157  val aTooSmallReg = RegEnable(aIsZero | lzcDiff(lzc_width), state(s_pre_0)) // a is zero or a smaller than d
158  aTooSmall := aTooSmallReg
159
160  val quotSign = Mux(state(s_idle), aSign ^ dSign, true.B) // if not s_idle then must be s_pre_1 & dIsZero, and that we have
161  val rSign = aSign
162  val quotSignReg = RegEnable(quotSign, startHandShake | (state(s_pre_1) & dIsZero))
163  val rSignReg = RegEnable(rSign, startHandShake)
164
165  val rShift = lzcDiff(0) // odd lzc diff, for SRT4
166  val rightShifted = Wire(UInt(len.W))
167  val rSumInit = Mux(aTooSmallReg | aIsZero, Cat(0.U(1.W), rightShifted, 0.U(3.W)), // right shift the dividend (which is already l-shifted)
168                    Mux(noIterReg, 0.U(itn_len.W), //
169                      Cat(0.U(3.W),
170                          Mux(rShift, Cat(0.U(1.W), aNormAbsReg(len - 1, 0)), Cat(aNormAbsReg(len - 1, 0), 0.U(1.W)))
171                        ) // Normal init value. 68, 67; For even lzcDiff, 0.001xxx0; for odd lzcDiff 0.0001xxx
172                      )
173                    ) // state is s_pre_1
174  val rCarryInit = 0.U(itn_len.W)
175
176  val rightShifter = Module(new RightShifter(len, lzc_width))
177  rightShifter.io.in := Mux(state(s_pre_1), aNormAbsReg(len - 1, 0), rPreShifted(len - 1, 0))
178  rightShifter.io.shiftNum := Mux(state(s_pre_1), aLZCReg,
179                                  Mux(aTooSmallReg | dIsZero, 0.U(lzc_width.W), dLZCReg))
180  rightShifter.io.msb := state(s_post_1) & rSignReg & rPreShifted(len)
181  rightShifted := rightShifter.io.out
182
183  // obtaining 1st quotient
184  val rSumInitTrunc = Cat(0.U(1.W), rSumInit(itn_len - 4, itn_len - 4 - 4 + 1)) // 0.00___
185  val mInitPos1 = MuxLookup(dNormAbsReg(len - 2, len - 2 - 3 + 1), "b00100".U(5.W))(
186    Seq(
187      0.U -> "b00100".U(5.W),
188      1.U -> "b00100".U(5.W),
189      2.U -> "b00100".U(5.W),
190      3.U -> "b00110".U(5.W),
191      4.U -> "b00110".U(5.W),
192      5.U -> "b00110".U(5.W),
193      6.U -> "b00110".U(5.W),
194      7.U -> "b01000".U(5.W),
195    )
196  )
197  val mInitPos2 = MuxLookup(dNormAbsReg(len - 2, len - 2 - 3 + 1), "b01100".U(5.W))(
198    Seq(
199      0.U -> "b01100".U(5.W),
200      1.U -> "b01110".U(5.W),
201      2.U -> "b01111".U(5.W),
202      3.U -> "b10000".U(5.W),
203      4.U -> "b10010".U(5.W),
204      5.U -> "b10100".U(5.W),
205      6.U -> "b10110".U(5.W),
206      7.U -> "b10110".U(5.W),
207    )
208  )
209  val initCmpPos1 = rSumInitTrunc >= mInitPos1
210  val initCmpPos2 = rSumInitTrunc >= mInitPos2
211  val qInit = Mux(initCmpPos2, UIntToOH(quot_pos_2, 5), Mux(initCmpPos1, UIntToOH(quot_pos_1, 5), UIntToOH(quot_0, 5)))
212  val qPrev = Mux(state(s_pre_1), qInit, qIterEnd)
213  val qPrevReg = RegEnable(qPrev, state(s_pre_1) | state(s_iter))
214  val specialDivisorReg = RegEnable(dNormAbsReg(len - 2, len - 2 - 3 + 1) === 0.U, state(s_pre_1)) // d=0.1000xxx
215  // rCarry and rSum in Iteration
216  val qXd = Mux1H(Seq(
217    qPrevReg(quot_neg_2) -> Cat(dNormAbsReg(len - 1, 0), 0.U(4.W)), // 68, 67 1.xxxxx0000
218    qPrevReg(quot_neg_1) -> Cat(0.U(1.W), dNormAbsReg(len - 1, 0), 0.U(3.W)), // 0.1xxxxx000
219    qPrevReg(quot_0)     -> 0.U(itn_len.W),
220    qPrevReg(quot_pos_1) -> ~Cat(0.U(1.W), dNormAbsReg(len - 1, 0), 0.U(3.W)), // don't forget to plus 1 later
221    qPrevReg(quot_pos_2) -> ~Cat(dNormAbsReg(len - 1, 0), 0.U(4.W))  // don't forget to plus 1 later
222  ))
223  val csa = Module(new CSA3_2(itn_len))
224
225  val rSumIter = csa.io.out(0)
226  val rCarryIter = Cat(csa.io.out(1)(itn_len - 2, 0), qPrevReg(quot_pos_1) | qPrevReg(quot_pos_2))
227  val rSumReg = RegEnable(Mux(state(s_pre_1), rSumInit, rSumIter), state(s_pre_1) | state(s_iter)) // 68, 67
228  val rCarryReg = RegEnable(Mux(state(s_pre_1), rCarryInit, rCarryIter), state(s_pre_1) | state(s_iter))
229  csa.io.in(0) := rSumReg << 2
230  csa.io.in(1) := rCarryReg << 2
231  csa.io.in(2) := qXd
232
233  val qds = Module(new SRT4QDS(len, itn_len))
234  qds.io.remSum := rSumReg
235  qds.io.remCarry := rCarryReg
236  qds.io.d := dNormAbsReg(len - 1, 0) // Maybe optimize here to lower power consumption?
237  qds.io.specialDivisor := specialDivisorReg
238  qds.io.qPrev := qPrevReg
239  qIterEnd := qds.io.qIterEnd
240
241  //on the fly conversion
242  val quotIterNext = Wire(UInt(len.W))
243  val quotIterM1Next = Wire(UInt(len.W))
244  quotIterNext := Mux1H(Seq(
245    qPrevReg(quot_pos_2) -> (quotIterReg << 2 | "b10".U),
246    qPrevReg(quot_pos_1) -> (quotIterReg << 2 | "b01".U),
247    qPrevReg(quot_0)     -> (quotIterReg << 2 | "b00".U),
248    qPrevReg(quot_neg_1) -> (quotM1IterReg << 2 | "b11".U),
249    qPrevReg(quot_neg_2) -> (quotM1IterReg << 2 | "b10".U)
250  ))
251  quotIterM1Next := Mux1H(Seq(
252    qPrevReg(quot_pos_2) -> (quotIterReg << 2 | "b01".U),
253    qPrevReg(quot_pos_1) -> (quotIterReg << 2 | "b00".U),
254    qPrevReg(quot_0)     -> (quotM1IterReg << 2 | "b11".U),
255    qPrevReg(quot_neg_1) -> (quotM1IterReg << 2 | "b10".U),
256    qPrevReg(quot_neg_2) -> (quotM1IterReg << 2 | "b01".U)
257  ))
258
259
260  quotIter := Mux(state(s_pre_1),
261                      Mux(dIsZero, VecInit(Seq.fill(len)(true.B)).asUInt,
262                        Mux(noIterReg, aNormAbsReg(len - 1, 0), 0.U(len.W))),
263                      Mux(state(s_iter), quotIterNext,
264                        Mux(quotSignReg, aInverter, quotIterReg)))
265  quotM1Iter := Mux(state(s_pre_1),
266                        0.U(len.W), Mux(state(s_iter), quotIterM1Next,
267                          Mux(quotSignReg, dInverter, quotM1IterReg)))
268
269
270  // iter num
271  val iterNum = Wire(UInt((lzc_width - 1).W))
272  val iterNumReg = RegEnable(iterNum, state(s_pre_1) | state(s_iter))
273
274  iterNum := Mux(state(s_pre_1), lzcDiff(lzc_width - 1, 1) +% lzcDiff(0), iterNumReg -% 1.U)
275  finalIter := iterNumReg === 0.U
276
277  // Post Process
278
279  when(rSignReg) {
280    rNext := ~rSumReg + ~rCarryReg + 2.U
281    rNextPd := ~rSumReg + ~rCarryReg + ~Cat(0.U(1.W), dNormAbsReg(len - 1, 0), 0.U(3.W)) + 3.U
282  } .otherwise {
283    rNext := rSumReg + rCarryReg
284    rNextPd := rSumReg + rCarryReg + Cat(0.U(1.W), dNormAbsReg(len - 1, 0), 0.U(3.W))
285  }
286
287  val r = aNormAbsReg
288  val rPd = dNormAbsReg
289  val rIsZero = ~(r.orR)
290  val needCorr = (~dIsZero & ~noIterReg) & Mux(rSignReg, ~r(len) & ~rIsZero, r(len)) // when we get pos rem for d<0 or neg rem for d>0
291  rPreShifted := Mux(needCorr, rPd, r)
292  val rFinal = RegEnable(rightShifted, state(s_post_1))// right shifted remainder. shift by the number of bits divisor is shifted
293  val qFinal = Mux(needCorr, quotM1IterReg, quotIterReg)
294  val res = Mux(isHi, rFinal, qFinal)
295  io.out_data := Mux(isW,
296    SignExt(res(31, 0), len),
297    res
298  )
299  io.in_ready := state(s_idle)
300  io.out_valid := state(s_finish) // state === s_finish
301}
302
303class RightShifter(len: Int, lzc_width: Int) extends Module {
304  val io = IO(new Bundle() {
305    val shiftNum = Input(UInt(lzc_width.W))
306    val in = Input(UInt(len.W))
307    val msb = Input(Bool())
308    val out = Output(UInt(len.W))
309  })
310  require(len == 64 || len == 32)
311  val shift = io.shiftNum
312  val msb = io.msb
313  val s0 = Mux(shift(0), Cat(VecInit(Seq.fill(1)(msb)).asUInt, io.in(len - 1, 1)), io.in)
314  val s1 = Mux(shift(1), Cat(VecInit(Seq.fill(2)(msb)).asUInt, s0(len - 1, 2)), s0)
315  val s2 = Mux(shift(2), Cat(VecInit(Seq.fill(4)(msb)).asUInt, s1(len - 1, 4)), s1)
316  val s3 = Mux(shift(3), Cat(VecInit(Seq.fill(8)(msb)).asUInt, s2(len - 1, 8)), s2)
317  val s4 = Mux(shift(4), Cat(VecInit(Seq.fill(16)(msb)).asUInt, s3(len - 1, 16)), s3)
318  val s5 = Wire(UInt(len.W))
319  if (len == 64) {
320    s5 := Mux(shift(5), Cat(VecInit(Seq.fill(32)(msb)).asUInt, s4(len - 1, 32)), s4)
321  } else if (len == 32) {
322    s5 := s4
323  }
324  io.out := s5
325}
326
327object mLookUpTable {
328  // Usage :
329  // result := decoder(QMCMinimizer, index, mLookupTable.xxx)
330  val minus_m = Seq(
331    Seq( // -m[-1]
332      0.U -> "b00_11010".U,
333      1.U -> "b00_11110".U,
334      2.U -> "b01_00000".U,
335      3.U -> "b01_00100".U,
336      4.U -> "b01_00110".U,
337      5.U -> "b01_01010".U,
338      6.U -> "b01_01100".U,
339      7.U -> "b01_10000".U
340    ),
341    Seq( // -m[0]
342      0.U -> "b000_0101".U,
343      1.U -> "b000_0110".U,
344      2.U -> "b000_0110".U,
345      3.U -> "b000_0110".U,
346      4.U -> "b000_1001".U,
347      5.U -> "b000_1000".U,
348      6.U -> "b000_1000".U,
349      7.U -> "b000_1000".U
350    ),
351    Seq( //-m[1]
352      0.U -> "b111_1101".U,
353      1.U -> "b111_1100".U,
354      2.U -> "b111_1100".U,
355      3.U -> "b111_1100".U,
356      4.U -> "b111_1011".U,
357      5.U -> "b111_1010".U,
358      6.U -> "b111_1010".U,
359      7.U -> "b111_1010".U
360    ),
361    Seq( //-m[2]
362      0.U -> "b11_01000".U,
363      1.U -> "b11_00100".U,
364      2.U -> "b11_00010".U,
365      3.U -> "b10_11110".U,
366      4.U -> "b10_11100".U,
367      5.U -> "b10_11000".U,
368      6.U -> "b10_10110".U,
369      7.U -> "b10_10010".U
370    ))
371}
372
373class SRT4QDS(len: Int, itn_len: Int) extends Module {
374  // srt4 quotientr digit selection
375  val io = IO(new Bundle() {
376    val remSum = Input(UInt(itn_len.W)) // 68, 67
377    val remCarry = Input(UInt(itn_len.W))
378    val d = Input(UInt(len.W)) // 64, 64
379    val specialDivisor = Input(Bool())
380    val qPrev = Input(UInt(5.W))
381    val qIterEnd = Output(UInt(5.W))
382  })
383  val remSumX16 = io.remSum << 4 // 72, 67 Top 2 bits unused
384  val remCarryX16 = io.remCarry << 4
385  def trunc25(rem: UInt): UInt = {rem(itn_len, itn_len - 7 + 1)}
386  def trunc34(rem: UInt): UInt = {rem(itn_len + 1, itn_len + 1 - 7 + 1)}
387
388  val quot_neg_2 :: quot_neg_1 :: quot_0 :: quot_pos_1 :: quot_pos_2 :: Nil = Enum(5)
389
390  val d = Cat(0.U(1.W), io.d, 0.U(3.W)) // 68, 67
391  val (dX4, dX8, dXNeg4, dXNeg8) = (d << 2, d(itn_len - 2, 0) << 3, ~(d << 2), ~(d(itn_len - 2, 0) << 3)) // 70, 67
392  val dForLookup = io.d(len - 2, len - 2 - 3 + 1)
393
394  val dXq = Mux1H(Seq(
395    io.qPrev(quot_neg_2) -> dX8,
396    io.qPrev(quot_neg_1) -> dX4,
397    io.qPrev(quot_0) -> 0.U((itn_len + 2).W),
398    io.qPrev(quot_pos_1) -> dXNeg4,
399    io.qPrev(quot_pos_2) -> dXNeg8
400  ))
401  val signs = VecInit(Seq.tabulate(4){ // -1 0 1 2
402    i => {
403      val csa1 = Module(new CSA3_2(7))
404      val csa2 = Module(new CSA3_2(7))
405      if (i == 1 || i == 2) {
406        csa1.io.in(0) := trunc34(remSumX16)
407        csa1.io.in(1) := trunc34(remCarryX16)
408        csa2.io.in(2) := trunc34(dXq)
409      } else {
410        csa1.io.in(0) := trunc25(remSumX16)
411        csa1.io.in(1) := trunc25(remCarryX16)
412        csa2.io.in(2) := trunc25(dXq)
413      }
414      csa1.io.in(2) := MuxLookup(dForLookup, "b0000000".U)(mLookUpTable.minus_m(i))
415      csa2.io.in(0) := csa1.io.out(0)
416      csa2.io.in(1) := csa1.io.out(1)(5, 0) << 1
417      (csa2.io.out(0) + (csa2.io.out(1)(5, 0) << 1))(6)
418    }
419  })
420  val qVec = Wire(Vec(5, Bool()))
421  qVec(quot_neg_2) := signs(0) && signs(1) && signs(2)
422  qVec(quot_neg_1) := ~signs(0) && signs(1) && signs(2)
423  qVec(quot_0) := signs(2) && ~signs(1)
424  qVec(quot_pos_1) := signs(3) && ~signs(2) && ~signs(1)
425  qVec(quot_pos_2) := ~signs(3) && ~signs(2) && ~signs(1)
426  io.qIterEnd := qVec.asUInt
427  // assert(PopCount(qVec) === 1.U)
428}
429
430
431class SRT4Divider(len: Int)(implicit p: Parameters) extends AbstractDivider(len) {
432
433  val newReq = io.in.fire
434
435  val uop = io.in.bits.uop
436  val uopReg = RegEnable(uop, newReq)
437  val ctrlReg = RegEnable(ctrl, newReq)
438
439  val divDataModule = Module(new SRT4DividerDataModule(len))
440
441  val kill_w = uop.robIdx.needFlush(io.redirectIn)
442  val kill_r = !divDataModule.io.in_ready && uopReg.robIdx.needFlush(io.redirectIn)
443
444  divDataModule.io.src(0) := io.in.bits.src(0)
445  divDataModule.io.src(1) := io.in.bits.src(1)
446  divDataModule.io.valid := io.in.valid
447  divDataModule.io.sign := sign
448  divDataModule.io.kill_w := kill_w
449  divDataModule.io.kill_r := kill_r
450  divDataModule.io.isHi := ctrlReg.isHi
451  divDataModule.io.isW := ctrlReg.isW
452  divDataModule.io.out_ready := io.out.ready
453
454  io.in.ready := divDataModule.io.in_ready
455  io.out.valid := divDataModule.io.out_valid
456  io.out.bits.data := divDataModule.io.out_data
457  io.out.bits.uop := uopReg
458}
459