xref: /XiangShan/src/main/scala/xiangshan/backend/fu/wrapper/VIAluFix.scala (revision f7063a43ab34da917ba6c670d21871314340c550)
1package xiangshan.backend.fu.wrapper
2
3import org.chipsalliance.cde.config.Parameters
4import chisel3.{VecInit, _}
5import chisel3.util._
6import chisel3.util.experimental.decode.{QMCMinimizer, TruthTable, decoder}
7import utility.DelayN
8import utils.XSError
9import xiangshan.XSCoreParamsKey
10import xiangshan.backend.fu.vector.Bundles.{VConfig, VSew, ma}
11import xiangshan.backend.fu.vector.{Mgu, Mgtu, VecPipedFuncUnit}
12import xiangshan.backend.fu.vector.Utils.VecDataToMaskDataVec
13import xiangshan.backend.fu.vector.utils.VecDataSplitModule
14import xiangshan.backend.fu.{FuConfig, FuType}
15import xiangshan.ExceptionNO
16import yunsuan.{OpType, VialuFixType}
17import yunsuan.vector.alu.{VIntFixpAlu64b, VIntFixpDecode, VIntFixpTable}
18import yunsuan.encoding.{VdType, Vs1IntType, Vs2IntType}
19import yunsuan.encoding.Opcode.VialuOpcode
20import yunsuan.vector.SewOH
21
22class VIAluSrcTypeIO extends Bundle {
23  val in = Input(new Bundle {
24    val fuOpType: UInt = OpType()
25    val vsew: UInt = VSew()
26    val isReverse: Bool = Bool() // vrsub, vrdiv
27    val isExt: Bool = Bool()
28    val isDstMask: Bool = Bool() // vvm, vvvm, mmm
29    val isMove: Bool = Bool() // vmv.s.x, vmv.v.v, vmv.v.x, vmv.v.i
30  })
31  val out = Output(new Bundle {
32    val vs1Type: UInt = Vs1IntType()
33    val vs2Type: UInt = Vs2IntType()
34    val vdType: UInt = VdType()
35    val illegal: Bool = Bool()
36    val isVextF2: Bool = Bool()
37    val isVextF4: Bool = Bool()
38    val isVextF8: Bool = Bool()
39  })
40}
41
42class VIAluSrcTypeModule extends Module {
43  val io: VIAluSrcTypeIO = IO(new VIAluSrcTypeIO)
44
45  private val vsew = io.in.vsew
46  private val isExt = io.in.isExt
47  private val isDstMask = io.in.isDstMask
48
49  private val opcode = VialuFixType.getOpcode(io.in.fuOpType)
50  private val isSign = VialuFixType.isSigned(io.in.fuOpType)
51  private val format = VialuFixType.getFormat(io.in.fuOpType)
52
53  private val vsewX2 = vsew + 1.U
54  private val vsewF2 = vsew - 1.U
55  private val vsewF4 = vsew - 2.U
56  private val vsewF8 = vsew - 3.U
57
58  private val isAddSub = opcode === VialuOpcode.vadd || opcode === VialuOpcode.vsub
59  private val isShiftRight = Seq(VialuOpcode.vsrl, VialuOpcode.vsra, VialuOpcode.vssrl, VialuOpcode.vssra).map(fmt => fmt === format).reduce(_ || _)
60  private val isVext = opcode === VialuOpcode.vext
61
62  private val isWiden = isAddSub && Seq(VialuFixType.FMT.VVW, VialuFixType.FMT.WVW).map(fmt => fmt === format).reduce(_ || _)
63  private val isNarrow = isShiftRight && format === VialuFixType.FMT.WVV
64  private val isVextF2 = isVext && format === VialuFixType.FMT.VF2
65  private val isVextF4 = isVext && format === VialuFixType.FMT.VF4
66  private val isVextF8 = isVext && format === VialuFixType.FMT.VF8
67
68  // check illegal
69  private val widenIllegal = isWiden && vsewX2 === VSew.e8
70  private val narrowIllegal = isNarrow && vsewF2 === VSew.e64
71  private val vextIllegal = (isVextF2 && (vsewF2 === VSew.e64)) ||
72    (isVextF4 && (vsewF4 === VSew.e64)) ||
73    (isVextF8 && (vsewF8 === VSew.e64))
74  // Todo: use it
75  private val illegal = widenIllegal || narrowIllegal || vextIllegal
76
77  private val intType = Cat(0.U(1.W), isSign)
78
79  private class Vs2Vs1VdSew extends Bundle {
80    val vs2 = VSew()
81    val vs1 = VSew()
82    val vd = VSew()
83  }
84
85  private class Vs2Vs1VdType extends Bundle {
86    val vs2 = Vs2IntType()
87    val vs1 = Vs1IntType()
88    val vd = VdType()
89  }
90
91  private val addSubSews = Mux1H(Seq(
92    (format === VialuFixType.FMT.VVV) -> Cat(vsew, vsew, vsew),
93    (format === VialuFixType.FMT.VVW) -> Cat(vsew, vsew, vsewX2),
94    (format === VialuFixType.FMT.WVW) -> Cat(vsewX2, vsew, vsewX2),
95    (format === VialuFixType.FMT.WVV) -> Cat(vsewX2, vsew, vsew),
96  )).asTypeOf(new Vs2Vs1VdSew)
97
98  private val vextSews = Mux1H(Seq(
99    (format === VialuFixType.FMT.VF2) -> Cat(vsewF2, vsewF2, vsew),
100    (format === VialuFixType.FMT.VF4) -> Cat(vsewF4, vsewF4, vsew),
101    (format === VialuFixType.FMT.VF8) -> Cat(vsewF8, vsewF8, vsew),
102  )).asTypeOf(new Vs2Vs1VdSew)
103
104  private val maskTypes = Mux1H(Seq(
105    (format === VialuFixType.FMT.VVM) -> Cat(Cat(intType, vsew), Cat(intType, vsew), VdType.mask),
106    (format === VialuFixType.FMT.VVMM) -> Cat(Cat(intType, vsew), Cat(intType, vsew), VdType.mask),
107    (format === VialuFixType.FMT.MMM) -> Cat(Vs2IntType.mask, Vs1IntType.mask, VdType.mask),
108  )).asTypeOf(new Vs2Vs1VdType)
109
110  private val vs2Type = Mux1H(Seq(
111    isDstMask -> maskTypes.vs2,
112    isExt -> Cat(intType, vextSews.vs2),
113    (!isExt && !isDstMask) -> Cat(intType, addSubSews.vs2),
114  ))
115  private val vs1Type = Mux1H(Seq(
116    isDstMask -> maskTypes.vs1,
117    isExt -> Cat(intType, vextSews.vs1),
118    (!isExt && !isDstMask) -> Cat(intType, addSubSews.vs1),
119  ))
120  private val vdType = Mux1H(Seq(
121    isDstMask -> maskTypes.vd,
122    isExt -> Cat(intType, vextSews.vd),
123    (!isExt && !isDstMask) -> Cat(intType, addSubSews.vd),
124  ))
125
126  io.out.vs2Type := vs2Type
127  io.out.vs1Type := vs1Type
128  io.out.vdType := vdType
129  io.out.illegal := illegal
130  io.out.isVextF2 := isVextF2
131  io.out.isVextF4 := isVextF4
132  io.out.isVextF8 := isVextF8
133}
134
135class VIAluFix(cfg: FuConfig)(implicit p: Parameters) extends VecPipedFuncUnit(cfg) {
136  XSError(io.in.valid && io.in.bits.ctrl.fuOpType === VialuFixType.dummy, "VialuF OpType not supported")
137
138  // config params
139  private val dataWidth = cfg.dataBits
140  private val dataWidthOfDataModule = 64
141  private val numVecModule = dataWidth / dataWidthOfDataModule
142
143  // modules
144  private val typeMod = Module(new VIAluSrcTypeModule)
145  private val vs2Split = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
146  private val vs1Split = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
147  private val oldVdSplit = Module(new VecDataSplitModule(dataWidth, dataWidthOfDataModule))
148  private val vIntFixpAlus = Seq.fill(numVecModule)(Module(new VIntFixpAlu64b))
149  private val mgu = Module(new Mgu(dataWidth))
150  private val mgtu = Module(new Mgtu(dataWidth))
151
152  /**
153   * [[typeMod]]'s in connection
154   */
155  typeMod.io.in.fuOpType := fuOpType
156  typeMod.io.in.vsew := vsew
157  typeMod.io.in.isReverse := isReverse
158  typeMod.io.in.isExt := isExt
159  typeMod.io.in.isDstMask := vecCtrl.isDstMask
160  typeMod.io.in.isMove := isMove
161
162  private val vs2GroupedVec32b: Vec[UInt] = VecInit(vs2Split.io.outVec32b.zipWithIndex.groupBy(_._2 % 2).map(x => x._1 -> x._2.map(_._1)).values.map(x => Cat(x.reverse)).toSeq)
163  private val vs2GroupedVec16b: Vec[UInt] = VecInit(vs2Split.io.outVec16b.zipWithIndex.groupBy(_._2 % 2).map(x => x._1 -> x._2.map(_._1)).values.map(x => Cat(x.reverse)).toSeq)
164  private val vs2GroupedVec8b: Vec[UInt] = VecInit(vs2Split.io.outVec8b.zipWithIndex.groupBy(_._2 % 2).map(x => x._1 -> x._2.map(_._1)).values.map(x => Cat(x.reverse)).toSeq)
165  private val vs1GroupedVec: Vec[UInt] = VecInit(vs1Split.io.outVec32b.zipWithIndex.groupBy(_._2 % 2).map(x => x._1 -> x._2.map(_._1)).values.map(x => Cat(x.reverse)).toSeq)
166
167  /**
168   * In connection of [[vs2Split]], [[vs1Split]] and [[oldVdSplit]]
169   */
170  vs2Split.io.inVecData := vs2
171  vs1Split.io.inVecData := vs1
172  oldVdSplit.io.inVecData := oldVd
173
174  /**
175   * [[vIntFixpAlus]]'s in connection
176   */
177  private val opcode = VialuFixType.getOpcode(inCtrl.fuOpType).asTypeOf(vIntFixpAlus.head.io.opcode)
178  private val vs1Type = typeMod.io.out.vs1Type
179  private val vs2Type = typeMod.io.out.vs2Type
180  private val vdType = typeMod.io.out.vdType
181  private val isVextF2 = typeMod.io.out.isVextF2
182  private val isVextF4 = typeMod.io.out.isVextF4
183  private val isVextF8 = typeMod.io.out.isVextF8
184
185  private val truthTable = TruthTable(VIntFixpTable.table, VIntFixpTable.default)
186  private val decoderOut = decoder(QMCMinimizer, Cat(opcode.op), truthTable)
187  private val vIntFixpDecode = decoderOut.asTypeOf(new VIntFixpDecode)
188  private val isFixp = Mux(vIntFixpDecode.misc, opcode.isScalingShift, opcode.isSatAdd || opcode.isAvgAdd)
189  private val widen = opcode.isAddSub && vs1Type(1, 0) =/= vdType(1, 0)
190  private val widen_vs2 = widen && vs2Type(1, 0) =/= vdType(1, 0)
191  private val eewVs1 = SewOH(vs1Type(1, 0))
192  private val eewVd = SewOH(vdType(1, 0))
193
194  // Extension instructions
195  private val vf2 = isVextF2
196  private val vf4 = isVextF4
197  private val vf8 = isVextF8
198
199  private val vs1VecUsed: Vec[UInt] = Mux(widen || isNarrow, vs1GroupedVec, vs1Split.io.outVec64b)
200  private val vs2VecUsed = Wire(Vec(numVecModule, UInt(64.W)))
201  when(vf2) {
202    vs2VecUsed := vs2GroupedVec32b
203  }.elsewhen(vf4) {
204    vs2VecUsed := vs2GroupedVec16b
205  }.elsewhen(vf8) {
206    vs2VecUsed := vs2GroupedVec8b
207  }.otherwise {
208    vs2VecUsed := vs2Split.io.outVec64b
209  }
210
211  private val vs2Adder = Mux(widen_vs2, vs2GroupedVec32b, vs2Split.io.outVec64b)
212
213  // mask
214  private val maskDataVec: Vec[UInt] = VecDataToMaskDataVec(srcMask, vsew)
215  private val maskIdx = Mux(isNarrow, (vuopIdx >> 1.U).asUInt, vuopIdx)
216  private val eewVd_is_1b = vdType === VdType.mask
217  private val maskUsed = splitMask(maskDataVec(maskIdx), Mux(eewVd_is_1b, eewVs1, eewVd))
218
219  private val oldVdUsed = splitMask(VecDataToMaskDataVec(oldVd, vs1Type(1, 0))(vuopIdx), eewVs1)
220
221  vIntFixpAlus.zipWithIndex.foreach {
222    case (mod, i) =>
223      mod.io.fire := io.in.valid
224      mod.io.opcode := opcode
225
226      mod.io.info.vm := vm
227      mod.io.info.ma := vma
228      mod.io.info.ta := vta
229      mod.io.info.vlmul := vlmul
230      mod.io.info.vl := vl
231      mod.io.info.vstart := vstart
232      mod.io.info.uopIdx := vuopIdx
233      mod.io.info.vxrm := vxrm
234
235      mod.io.srcType(0) := vs2Type
236      mod.io.srcType(1) := vs1Type
237      mod.io.vdType := vdType
238      mod.io.narrow := isNarrow
239      mod.io.isSub := vIntFixpDecode.sub
240      mod.io.isMisc := vIntFixpDecode.misc
241      mod.io.isFixp := isFixp
242      mod.io.widen := widen
243      mod.io.widen_vs2 := widen_vs2
244      mod.io.vs1 := vs1VecUsed(i)
245      mod.io.vs2_adder := vs2Adder(i)
246      mod.io.vs2_misc := vs2VecUsed(i)
247      mod.io.vmask := maskUsed(i)
248      mod.io.oldVd := oldVdUsed(i)
249  }
250
251  /**
252   * [[mgu]]'s in connection
253   */
254  //private val outEewVs1 = DelayN(eewVs1, latency)
255  private val outEewVs1 = SNReg(eewVs1, latency)
256
257  private val outVd = Cat(vIntFixpAlus.reverse.map(_.io.vd))
258  private val outCmp = Mux1H(outEewVs1.oneHot, Seq(8, 4, 2, 1).map(
259    k => Cat(vIntFixpAlus.reverse.map(_.io.cmpOut(k - 1, 0)))))
260  private val outNarrow = Cat(vIntFixpAlus.reverse.map(_.io.narrowVd))
261  private val outOpcode = VialuFixType.getOpcode(outCtrl.fuOpType).asTypeOf(vIntFixpAlus.head.io.opcode)
262
263  private val numBytes = dataWidth / 8
264  private val maxMaskIdx = numBytes
265  private val maxVdIdx = 8
266  private val elementsInOneUop = Mux1H(outEewVs1.oneHot, Seq(1, 2, 4, 8).map(k => (numBytes / k).U(5.W)))
267  private val vdIdx = outVecCtrl.vuopIdx(2, 0)
268  private val elementsComputed = Mux1H(Seq.tabulate(maxVdIdx)(i => (vdIdx === i.U) -> (elementsInOneUop * i.U)))
269  val outCmpWithTail = Wire(Vec(maxMaskIdx, UInt(1.W)))
270  // set the bits in vd to 1 if the index is larger than vl and vta is true
271  for (i <- 0 until maxMaskIdx) {
272    when(elementsComputed +& i.U >= outVl) {
273      // always operate under a tail-agnostic policy
274      outCmpWithTail(i) := 1.U
275    }.otherwise {
276      outCmpWithTail(i) := outCmp(i)
277    }
278  }
279
280  /* insts whose mask is not used to generate 'agnosticEn' and 'activeEn' in mgu:
281   * vadc, vmadc...
282   * vmerge
283   */
284  private val needNoMask = VialuFixType.needNoMask(outCtrl.fuOpType)
285  private val maskToMgu = Mux(needNoMask, allMaskTrue, outSrcMask)
286
287  private val outFormat = VialuFixType.getFormat(outCtrl.fuOpType)
288  private val outWiden = (outFormat === VialuFixType.FMT.VVW | outFormat === VialuFixType.FMT.WVW) & !outVecCtrl.isExt & !outVecCtrl.isDstMask
289  private val narrow = outVecCtrl.isNarrow
290  private val dstMask = outVecCtrl.isDstMask
291  private val outVxsat = Mux(narrow, Cat(vIntFixpAlus.reverse.map(_.io.vxsat(3, 0))), Cat(vIntFixpAlus.reverse.map(_.io.vxsat)))
292
293  // the result of narrow inst which needs concat
294  private val narrowNeedCat = outVecCtrl.vuopIdx(0).asBool && narrow
295  private val outNarrowVd = Mux(narrowNeedCat, Cat(outNarrow, outOldVd(dataWidth / 2 - 1, 0)), outNarrow)
296  private val outVxsatReal = Mux(narrowNeedCat, Cat(outVxsat(numBytes / 2 - 1, 0), 0.U((numBytes / 2).W)), outVxsat)
297
298  private val outEew = Mux(outWiden, outVecCtrl.vsew + 1.U, outVecCtrl.vsew)
299
300  /*
301   * vl of vmv.x.s is 1
302   */
303  private val outIsVmvsx = outOpcode.isVmvsx
304
305  /*
306   * when vstart >= vl, no need to update vd, the old value should be kept
307   */
308  private val outVstartGeVl = outVstart >= outVl
309
310  mgu.io.in.vd := MuxCase(outVd, Seq(
311    narrow -> outNarrowVd,
312    dstMask -> outCmpWithTail.asUInt,
313  ))
314  mgu.io.in.oldVd := outOldVd
315  mgu.io.in.mask := maskToMgu
316  mgu.io.in.info.ta := outVecCtrl.vta
317  mgu.io.in.info.ma := outVecCtrl.vma
318  mgu.io.in.info.vl := Mux(outIsVmvsx, 1.U, outVl)
319  mgu.io.in.info.vlmul := outVecCtrl.vlmul
320  mgu.io.in.info.valid := validVec.last
321  mgu.io.in.info.vstart := outVecCtrl.vstart
322  mgu.io.in.info.eew := outEew
323  mgu.io.in.info.vsew := outVecCtrl.vsew
324  mgu.io.in.info.vdIdx := outVecCtrl.vuopIdx
325  mgu.io.in.info.narrow := narrow
326  mgu.io.in.info.dstMask := dstMask
327  mgu.io.in.isIndexedVls := false.B
328
329  /**
330   * [[mgtu]]'s in connection, for vmask instructions
331   */
332  mgtu.io.in.vd := Mux(dstMask && !outVecCtrl.isOpMask, mgu.io.out.vd, outVd)
333  mgtu.io.in.vl := outVl
334
335  io.out.bits.res.data := Mux(outVstartGeVl, outOldVd, Mux(dstMask, mgtu.io.out.vd, mgu.io.out.vd))
336  io.out.bits.res.vxsat.get := Mux(outVstartGeVl, false.B, (outVxsatReal & mgu.io.out.active).orR)
337  io.out.bits.ctrl.exceptionVec.get(ExceptionNO.illegalInstr) := mgu.io.out.illegal && !outVstartGeVl
338
339  // util function
340  def splitMask(maskIn: UInt, sew: SewOH): Vec[UInt] = {
341    val maskWidth = maskIn.getWidth
342    val result = Wire(Vec(maskWidth / 8, UInt(8.W)))
343    for ((resultData, i) <- result.zipWithIndex) {
344      resultData := Mux1H(Seq(
345        sew.is8 -> maskIn(i * 8 + 7, i * 8),
346        sew.is16 -> Cat(0.U((8 - 4).W), maskIn(i * 4 + 3, i * 4)),
347        sew.is32 -> Cat(0.U((8 - 2).W), maskIn(i * 2 + 1, i * 2)),
348        sew.is64 -> Cat(0.U((8 - 1).W), maskIn(i)),
349      ))
350    }
351    result
352  }
353
354}