xref: /freebsd/contrib/llvm-project/llvm/lib/Target/X86/X86FixupVectorConstants.cpp (revision 5036d9652a5701d00e9e40ea942c278e9f77d33d)
1 //===-- X86FixupVectorConstants.cpp - optimize constant generation  -------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file examines all full size vector constant pool loads and attempts to
10 // replace them with smaller constant pool entries, including:
11 // * Converting AVX512 memory-fold instructions to their broadcast-fold form.
12 // * Using vzload scalar loads.
13 // * Broadcasting of full width loads.
14 // * Sign/Zero extension of full width loads.
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #include "X86.h"
19 #include "X86InstrFoldTables.h"
20 #include "X86InstrInfo.h"
21 #include "X86Subtarget.h"
22 #include "llvm/ADT/Statistic.h"
23 #include "llvm/CodeGen/MachineConstantPool.h"
24 
25 using namespace llvm;
26 
27 #define DEBUG_TYPE "x86-fixup-vector-constants"
28 
29 STATISTIC(NumInstChanges, "Number of instructions changes");
30 
31 namespace {
32 class X86FixupVectorConstantsPass : public MachineFunctionPass {
33 public:
34   static char ID;
35 
36   X86FixupVectorConstantsPass() : MachineFunctionPass(ID) {}
37 
38   StringRef getPassName() const override {
39     return "X86 Fixup Vector Constants";
40   }
41 
42   bool runOnMachineFunction(MachineFunction &MF) override;
43   bool processInstruction(MachineFunction &MF, MachineBasicBlock &MBB,
44                           MachineInstr &MI);
45 
46   // This pass runs after regalloc and doesn't support VReg operands.
47   MachineFunctionProperties getRequiredProperties() const override {
48     return MachineFunctionProperties().set(
49         MachineFunctionProperties::Property::NoVRegs);
50   }
51 
52 private:
53   const X86InstrInfo *TII = nullptr;
54   const X86Subtarget *ST = nullptr;
55   const MCSchedModel *SM = nullptr;
56 };
57 } // end anonymous namespace
58 
59 char X86FixupVectorConstantsPass::ID = 0;
60 
61 INITIALIZE_PASS(X86FixupVectorConstantsPass, DEBUG_TYPE, DEBUG_TYPE, false, false)
62 
63 FunctionPass *llvm::createX86FixupVectorConstants() {
64   return new X86FixupVectorConstantsPass();
65 }
66 
67 /// Normally, we only allow poison in vector splats. However, as this is part
68 /// of the backend, and working with the DAG representation, which currently
69 /// only natively represents undef values, we need to accept undefs here.
70 static Constant *getSplatValueAllowUndef(const ConstantVector *C) {
71   Constant *Res = nullptr;
72   for (Value *Op : C->operands()) {
73     Constant *OpC = cast<Constant>(Op);
74     if (isa<UndefValue>(OpC))
75       continue;
76     if (!Res)
77       Res = OpC;
78     else if (Res != OpC)
79       return nullptr;
80   }
81   return Res;
82 }
83 
84 // Attempt to extract the full width of bits data from the constant.
85 static std::optional<APInt> extractConstantBits(const Constant *C) {
86   unsigned NumBits = C->getType()->getPrimitiveSizeInBits();
87 
88   if (isa<UndefValue>(C))
89     return APInt::getZero(NumBits);
90 
91   if (auto *CInt = dyn_cast<ConstantInt>(C))
92     return CInt->getValue();
93 
94   if (auto *CFP = dyn_cast<ConstantFP>(C))
95     return CFP->getValue().bitcastToAPInt();
96 
97   if (auto *CV = dyn_cast<ConstantVector>(C)) {
98     if (auto *CVSplat = getSplatValueAllowUndef(CV)) {
99       if (std::optional<APInt> Bits = extractConstantBits(CVSplat)) {
100         assert((NumBits % Bits->getBitWidth()) == 0 && "Illegal splat");
101         return APInt::getSplat(NumBits, *Bits);
102       }
103     }
104 
105     APInt Bits = APInt::getZero(NumBits);
106     for (unsigned I = 0, E = CV->getNumOperands(); I != E; ++I) {
107       Constant *Elt = CV->getOperand(I);
108       std::optional<APInt> SubBits = extractConstantBits(Elt);
109       if (!SubBits)
110         return std::nullopt;
111       assert(NumBits == (E * SubBits->getBitWidth()) &&
112              "Illegal vector element size");
113       Bits.insertBits(*SubBits, I * SubBits->getBitWidth());
114     }
115     return Bits;
116   }
117 
118   if (auto *CDS = dyn_cast<ConstantDataSequential>(C)) {
119     bool IsInteger = CDS->getElementType()->isIntegerTy();
120     bool IsFloat = CDS->getElementType()->isHalfTy() ||
121                    CDS->getElementType()->isBFloatTy() ||
122                    CDS->getElementType()->isFloatTy() ||
123                    CDS->getElementType()->isDoubleTy();
124     if (IsInteger || IsFloat) {
125       APInt Bits = APInt::getZero(NumBits);
126       unsigned EltBits = CDS->getElementType()->getPrimitiveSizeInBits();
127       for (unsigned I = 0, E = CDS->getNumElements(); I != E; ++I) {
128         if (IsInteger)
129           Bits.insertBits(CDS->getElementAsAPInt(I), I * EltBits);
130         else
131           Bits.insertBits(CDS->getElementAsAPFloat(I).bitcastToAPInt(),
132                           I * EltBits);
133       }
134       return Bits;
135     }
136   }
137 
138   return std::nullopt;
139 }
140 
141 static std::optional<APInt> extractConstantBits(const Constant *C,
142                                                 unsigned NumBits) {
143   if (std::optional<APInt> Bits = extractConstantBits(C))
144     return Bits->zextOrTrunc(NumBits);
145   return std::nullopt;
146 }
147 
148 // Attempt to compute the splat width of bits data by normalizing the splat to
149 // remove undefs.
150 static std::optional<APInt> getSplatableConstant(const Constant *C,
151                                                  unsigned SplatBitWidth) {
152   const Type *Ty = C->getType();
153   assert((Ty->getPrimitiveSizeInBits() % SplatBitWidth) == 0 &&
154          "Illegal splat width");
155 
156   if (std::optional<APInt> Bits = extractConstantBits(C))
157     if (Bits->isSplat(SplatBitWidth))
158       return Bits->trunc(SplatBitWidth);
159 
160   // Detect general splats with undefs.
161   // TODO: Do we need to handle NumEltsBits > SplatBitWidth splitting?
162   if (auto *CV = dyn_cast<ConstantVector>(C)) {
163     unsigned NumOps = CV->getNumOperands();
164     unsigned NumEltsBits = Ty->getScalarSizeInBits();
165     unsigned NumScaleOps = SplatBitWidth / NumEltsBits;
166     if ((SplatBitWidth % NumEltsBits) == 0) {
167       // Collect the elements and ensure that within the repeated splat sequence
168       // they either match or are undef.
169       SmallVector<Constant *, 16> Sequence(NumScaleOps, nullptr);
170       for (unsigned Idx = 0; Idx != NumOps; ++Idx) {
171         if (Constant *Elt = CV->getAggregateElement(Idx)) {
172           if (isa<UndefValue>(Elt))
173             continue;
174           unsigned SplatIdx = Idx % NumScaleOps;
175           if (!Sequence[SplatIdx] || Sequence[SplatIdx] == Elt) {
176             Sequence[SplatIdx] = Elt;
177             continue;
178           }
179         }
180         return std::nullopt;
181       }
182       // Extract the constant bits forming the splat and insert into the bits
183       // data, leave undef as zero.
184       APInt SplatBits = APInt::getZero(SplatBitWidth);
185       for (unsigned I = 0; I != NumScaleOps; ++I) {
186         if (!Sequence[I])
187           continue;
188         if (std::optional<APInt> Bits = extractConstantBits(Sequence[I])) {
189           SplatBits.insertBits(*Bits, I * Bits->getBitWidth());
190           continue;
191         }
192         return std::nullopt;
193       }
194       return SplatBits;
195     }
196   }
197 
198   return std::nullopt;
199 }
200 
201 // Split raw bits into a constant vector of elements of a specific bit width.
202 // NOTE: We don't always bother converting to scalars if the vector length is 1.
203 static Constant *rebuildConstant(LLVMContext &Ctx, Type *SclTy,
204                                  const APInt &Bits, unsigned NumSclBits) {
205   unsigned BitWidth = Bits.getBitWidth();
206 
207   if (NumSclBits == 8) {
208     SmallVector<uint8_t> RawBits;
209     for (unsigned I = 0; I != BitWidth; I += 8)
210       RawBits.push_back(Bits.extractBits(8, I).getZExtValue());
211     return ConstantDataVector::get(Ctx, RawBits);
212   }
213 
214   if (NumSclBits == 16) {
215     SmallVector<uint16_t> RawBits;
216     for (unsigned I = 0; I != BitWidth; I += 16)
217       RawBits.push_back(Bits.extractBits(16, I).getZExtValue());
218     if (SclTy->is16bitFPTy())
219       return ConstantDataVector::getFP(SclTy, RawBits);
220     return ConstantDataVector::get(Ctx, RawBits);
221   }
222 
223   if (NumSclBits == 32) {
224     SmallVector<uint32_t> RawBits;
225     for (unsigned I = 0; I != BitWidth; I += 32)
226       RawBits.push_back(Bits.extractBits(32, I).getZExtValue());
227     if (SclTy->isFloatTy())
228       return ConstantDataVector::getFP(SclTy, RawBits);
229     return ConstantDataVector::get(Ctx, RawBits);
230   }
231 
232   assert(NumSclBits == 64 && "Unhandled vector element width");
233 
234   SmallVector<uint64_t> RawBits;
235   for (unsigned I = 0; I != BitWidth; I += 64)
236     RawBits.push_back(Bits.extractBits(64, I).getZExtValue());
237   if (SclTy->isDoubleTy())
238     return ConstantDataVector::getFP(SclTy, RawBits);
239   return ConstantDataVector::get(Ctx, RawBits);
240 }
241 
242 // Attempt to rebuild a normalized splat vector constant of the requested splat
243 // width, built up of potentially smaller scalar values.
244 static Constant *rebuildSplatCst(const Constant *C, unsigned /*NumBits*/,
245                                  unsigned /*NumElts*/, unsigned SplatBitWidth) {
246   // TODO: Truncate to NumBits once ConvertToBroadcastAVX512 support this.
247   std::optional<APInt> Splat = getSplatableConstant(C, SplatBitWidth);
248   if (!Splat)
249     return nullptr;
250 
251   // Determine scalar size to use for the constant splat vector, clamping as we
252   // might have found a splat smaller than the original constant data.
253   Type *SclTy = C->getType()->getScalarType();
254   unsigned NumSclBits = SclTy->getPrimitiveSizeInBits();
255   NumSclBits = std::min<unsigned>(NumSclBits, SplatBitWidth);
256 
257   // Fallback to i64 / double.
258   NumSclBits = (NumSclBits == 8 || NumSclBits == 16 || NumSclBits == 32)
259                    ? NumSclBits
260                    : 64;
261 
262   // Extract per-element bits.
263   return rebuildConstant(C->getContext(), SclTy, *Splat, NumSclBits);
264 }
265 
266 static Constant *rebuildZeroUpperCst(const Constant *C, unsigned NumBits,
267                                      unsigned /*NumElts*/,
268                                      unsigned ScalarBitWidth) {
269   Type *SclTy = C->getType()->getScalarType();
270   unsigned NumSclBits = SclTy->getPrimitiveSizeInBits();
271   LLVMContext &Ctx = C->getContext();
272 
273   if (NumBits > ScalarBitWidth) {
274     // Determine if the upper bits are all zero.
275     if (std::optional<APInt> Bits = extractConstantBits(C, NumBits)) {
276       if (Bits->countLeadingZeros() >= (NumBits - ScalarBitWidth)) {
277         // If the original constant was made of smaller elements, try to retain
278         // those types.
279         if (ScalarBitWidth > NumSclBits && (ScalarBitWidth % NumSclBits) == 0)
280           return rebuildConstant(Ctx, SclTy, *Bits, NumSclBits);
281 
282         // Fallback to raw integer bits.
283         APInt RawBits = Bits->zextOrTrunc(ScalarBitWidth);
284         return ConstantInt::get(Ctx, RawBits);
285       }
286     }
287   }
288 
289   return nullptr;
290 }
291 
292 static Constant *rebuildExtCst(const Constant *C, bool IsSExt,
293                                unsigned NumBits, unsigned NumElts,
294                                unsigned SrcEltBitWidth) {
295   unsigned DstEltBitWidth = NumBits / NumElts;
296   assert((NumBits % NumElts) == 0 && (NumBits % SrcEltBitWidth) == 0 &&
297          (DstEltBitWidth % SrcEltBitWidth) == 0 &&
298          (DstEltBitWidth > SrcEltBitWidth) && "Illegal extension width");
299 
300   if (std::optional<APInt> Bits = extractConstantBits(C, NumBits)) {
301     assert((Bits->getBitWidth() / DstEltBitWidth) == NumElts &&
302            (Bits->getBitWidth() % DstEltBitWidth) == 0 &&
303            "Unexpected constant extension");
304 
305     // Ensure every vector element can be represented by the src bitwidth.
306     APInt TruncBits = APInt::getZero(NumElts * SrcEltBitWidth);
307     for (unsigned I = 0; I != NumElts; ++I) {
308       APInt Elt = Bits->extractBits(DstEltBitWidth, I * DstEltBitWidth);
309       if ((IsSExt && Elt.getSignificantBits() > SrcEltBitWidth) ||
310           (!IsSExt && Elt.getActiveBits() > SrcEltBitWidth))
311         return nullptr;
312       TruncBits.insertBits(Elt.trunc(SrcEltBitWidth), I * SrcEltBitWidth);
313     }
314 
315     Type *Ty = C->getType();
316     return rebuildConstant(Ty->getContext(), Ty->getScalarType(), TruncBits,
317                            SrcEltBitWidth);
318   }
319 
320   return nullptr;
321 }
322 static Constant *rebuildSExtCst(const Constant *C, unsigned NumBits,
323                                 unsigned NumElts, unsigned SrcEltBitWidth) {
324   return rebuildExtCst(C, true, NumBits, NumElts, SrcEltBitWidth);
325 }
326 static Constant *rebuildZExtCst(const Constant *C, unsigned NumBits,
327                                 unsigned NumElts, unsigned SrcEltBitWidth) {
328   return rebuildExtCst(C, false, NumBits, NumElts, SrcEltBitWidth);
329 }
330 
331 bool X86FixupVectorConstantsPass::processInstruction(MachineFunction &MF,
332                                                      MachineBasicBlock &MBB,
333                                                      MachineInstr &MI) {
334   unsigned Opc = MI.getOpcode();
335   MachineConstantPool *CP = MI.getParent()->getParent()->getConstantPool();
336   bool HasSSE41 = ST->hasSSE41();
337   bool HasAVX2 = ST->hasAVX2();
338   bool HasDQI = ST->hasDQI();
339   bool HasBWI = ST->hasBWI();
340   bool HasVLX = ST->hasVLX();
341 
342   struct FixupEntry {
343     int Op;
344     int NumCstElts;
345     int MemBitWidth;
346     std::function<Constant *(const Constant *, unsigned, unsigned, unsigned)>
347         RebuildConstant;
348   };
349   auto FixupConstant = [&](ArrayRef<FixupEntry> Fixups, unsigned RegBitWidth,
350                            unsigned OperandNo) {
351 #ifdef EXPENSIVE_CHECKS
352     assert(llvm::is_sorted(Fixups,
353                            [](const FixupEntry &A, const FixupEntry &B) {
354                              return (A.NumCstElts * A.MemBitWidth) <
355                                     (B.NumCstElts * B.MemBitWidth);
356                            }) &&
357            "Constant fixup table not sorted in ascending constant size");
358 #endif
359     assert(MI.getNumOperands() >= (OperandNo + X86::AddrNumOperands) &&
360            "Unexpected number of operands!");
361     if (auto *C = X86::getConstantFromPool(MI, OperandNo)) {
362       RegBitWidth =
363           RegBitWidth ? RegBitWidth : C->getType()->getPrimitiveSizeInBits();
364       for (const FixupEntry &Fixup : Fixups) {
365         if (Fixup.Op) {
366           // Construct a suitable constant and adjust the MI to use the new
367           // constant pool entry.
368           if (Constant *NewCst = Fixup.RebuildConstant(
369                   C, RegBitWidth, Fixup.NumCstElts, Fixup.MemBitWidth)) {
370             unsigned NewCPI =
371                 CP->getConstantPoolIndex(NewCst, Align(Fixup.MemBitWidth / 8));
372             MI.setDesc(TII->get(Fixup.Op));
373             MI.getOperand(OperandNo + X86::AddrDisp).setIndex(NewCPI);
374             return true;
375           }
376         }
377       }
378     }
379     return false;
380   };
381 
382   // Attempt to detect a suitable vzload/broadcast/vextload from increasing
383   // constant bitwidths. Prefer vzload/broadcast/vextload for same bitwidth:
384   // - vzload shouldn't ever need a shuffle port to zero the upper elements and
385   // the fp/int domain versions are equally available so we don't introduce a
386   // domain crossing penalty.
387   // - broadcast sometimes need a shuffle port (especially for 8/16-bit
388   // variants), AVX1 only has fp domain broadcasts but AVX2+ have good fp/int
389   // domain equivalents.
390   // - vextload always needs a shuffle port and is only ever int domain.
391   switch (Opc) {
392   /* FP Loads */
393   case X86::MOVAPDrm:
394   case X86::MOVAPSrm:
395   case X86::MOVUPDrm:
396   case X86::MOVUPSrm:
397     // TODO: SSE3 MOVDDUP Handling
398     return FixupConstant({{X86::MOVSSrm, 1, 32, rebuildZeroUpperCst},
399                           {X86::MOVSDrm, 1, 64, rebuildZeroUpperCst}},
400                          128, 1);
401   case X86::VMOVAPDrm:
402   case X86::VMOVAPSrm:
403   case X86::VMOVUPDrm:
404   case X86::VMOVUPSrm:
405     return FixupConstant({{X86::VMOVSSrm, 1, 32, rebuildZeroUpperCst},
406                           {X86::VBROADCASTSSrm, 1, 32, rebuildSplatCst},
407                           {X86::VMOVSDrm, 1, 64, rebuildZeroUpperCst},
408                           {X86::VMOVDDUPrm, 1, 64, rebuildSplatCst}},
409                          128, 1);
410   case X86::VMOVAPDYrm:
411   case X86::VMOVAPSYrm:
412   case X86::VMOVUPDYrm:
413   case X86::VMOVUPSYrm:
414     return FixupConstant({{X86::VBROADCASTSSYrm, 1, 32, rebuildSplatCst},
415                           {X86::VBROADCASTSDYrm, 1, 64, rebuildSplatCst},
416                           {X86::VBROADCASTF128rm, 1, 128, rebuildSplatCst}},
417                          256, 1);
418   case X86::VMOVAPDZ128rm:
419   case X86::VMOVAPSZ128rm:
420   case X86::VMOVUPDZ128rm:
421   case X86::VMOVUPSZ128rm:
422     return FixupConstant({{X86::VMOVSSZrm, 1, 32, rebuildZeroUpperCst},
423                           {X86::VBROADCASTSSZ128rm, 1, 32, rebuildSplatCst},
424                           {X86::VMOVSDZrm, 1, 64, rebuildZeroUpperCst},
425                           {X86::VMOVDDUPZ128rm, 1, 64, rebuildSplatCst}},
426                          128, 1);
427   case X86::VMOVAPDZ256rm:
428   case X86::VMOVAPSZ256rm:
429   case X86::VMOVUPDZ256rm:
430   case X86::VMOVUPSZ256rm:
431     return FixupConstant(
432         {{X86::VBROADCASTSSZ256rm, 1, 32, rebuildSplatCst},
433          {X86::VBROADCASTSDZ256rm, 1, 64, rebuildSplatCst},
434          {X86::VBROADCASTF32X4Z256rm, 1, 128, rebuildSplatCst}},
435         256, 1);
436   case X86::VMOVAPDZrm:
437   case X86::VMOVAPSZrm:
438   case X86::VMOVUPDZrm:
439   case X86::VMOVUPSZrm:
440     return FixupConstant({{X86::VBROADCASTSSZrm, 1, 32, rebuildSplatCst},
441                           {X86::VBROADCASTSDZrm, 1, 64, rebuildSplatCst},
442                           {X86::VBROADCASTF32X4rm, 1, 128, rebuildSplatCst},
443                           {X86::VBROADCASTF64X4rm, 1, 256, rebuildSplatCst}},
444                          512, 1);
445     /* Integer Loads */
446   case X86::MOVDQArm:
447   case X86::MOVDQUrm: {
448     FixupEntry Fixups[] = {
449         {HasSSE41 ? X86::PMOVSXBQrm : 0, 2, 8, rebuildSExtCst},
450         {HasSSE41 ? X86::PMOVZXBQrm : 0, 2, 8, rebuildZExtCst},
451         {X86::MOVDI2PDIrm, 1, 32, rebuildZeroUpperCst},
452         {HasSSE41 ? X86::PMOVSXBDrm : 0, 4, 8, rebuildSExtCst},
453         {HasSSE41 ? X86::PMOVZXBDrm : 0, 4, 8, rebuildZExtCst},
454         {HasSSE41 ? X86::PMOVSXWQrm : 0, 2, 16, rebuildSExtCst},
455         {HasSSE41 ? X86::PMOVZXWQrm : 0, 2, 16, rebuildZExtCst},
456         {X86::MOVQI2PQIrm, 1, 64, rebuildZeroUpperCst},
457         {HasSSE41 ? X86::PMOVSXBWrm : 0, 8, 8, rebuildSExtCst},
458         {HasSSE41 ? X86::PMOVZXBWrm : 0, 8, 8, rebuildZExtCst},
459         {HasSSE41 ? X86::PMOVSXWDrm : 0, 4, 16, rebuildSExtCst},
460         {HasSSE41 ? X86::PMOVZXWDrm : 0, 4, 16, rebuildZExtCst},
461         {HasSSE41 ? X86::PMOVSXDQrm : 0, 2, 32, rebuildSExtCst},
462         {HasSSE41 ? X86::PMOVZXDQrm : 0, 2, 32, rebuildZExtCst}};
463     return FixupConstant(Fixups, 128, 1);
464   }
465   case X86::VMOVDQArm:
466   case X86::VMOVDQUrm: {
467     FixupEntry Fixups[] = {
468         {HasAVX2 ? X86::VPBROADCASTBrm : 0, 1, 8, rebuildSplatCst},
469         {HasAVX2 ? X86::VPBROADCASTWrm : 0, 1, 16, rebuildSplatCst},
470         {X86::VPMOVSXBQrm, 2, 8, rebuildSExtCst},
471         {X86::VPMOVZXBQrm, 2, 8, rebuildZExtCst},
472         {X86::VMOVDI2PDIrm, 1, 32, rebuildZeroUpperCst},
473         {HasAVX2 ? X86::VPBROADCASTDrm : X86::VBROADCASTSSrm, 1, 32,
474          rebuildSplatCst},
475         {X86::VPMOVSXBDrm, 4, 8, rebuildSExtCst},
476         {X86::VPMOVZXBDrm, 4, 8, rebuildZExtCst},
477         {X86::VPMOVSXWQrm, 2, 16, rebuildSExtCst},
478         {X86::VPMOVZXWQrm, 2, 16, rebuildZExtCst},
479         {X86::VMOVQI2PQIrm, 1, 64, rebuildZeroUpperCst},
480         {HasAVX2 ? X86::VPBROADCASTQrm : X86::VMOVDDUPrm, 1, 64,
481          rebuildSplatCst},
482         {X86::VPMOVSXBWrm, 8, 8, rebuildSExtCst},
483         {X86::VPMOVZXBWrm, 8, 8, rebuildZExtCst},
484         {X86::VPMOVSXWDrm, 4, 16, rebuildSExtCst},
485         {X86::VPMOVZXWDrm, 4, 16, rebuildZExtCst},
486         {X86::VPMOVSXDQrm, 2, 32, rebuildSExtCst},
487         {X86::VPMOVZXDQrm, 2, 32, rebuildZExtCst}};
488     return FixupConstant(Fixups, 128, 1);
489   }
490   case X86::VMOVDQAYrm:
491   case X86::VMOVDQUYrm: {
492     FixupEntry Fixups[] = {
493         {HasAVX2 ? X86::VPBROADCASTBYrm : 0, 1, 8, rebuildSplatCst},
494         {HasAVX2 ? X86::VPBROADCASTWYrm : 0, 1, 16, rebuildSplatCst},
495         {HasAVX2 ? X86::VPBROADCASTDYrm : X86::VBROADCASTSSYrm, 1, 32,
496          rebuildSplatCst},
497         {HasAVX2 ? X86::VPMOVSXBQYrm : 0, 4, 8, rebuildSExtCst},
498         {HasAVX2 ? X86::VPMOVZXBQYrm : 0, 4, 8, rebuildZExtCst},
499         {HasAVX2 ? X86::VPBROADCASTQYrm : X86::VBROADCASTSDYrm, 1, 64,
500          rebuildSplatCst},
501         {HasAVX2 ? X86::VPMOVSXBDYrm : 0, 8, 8, rebuildSExtCst},
502         {HasAVX2 ? X86::VPMOVZXBDYrm : 0, 8, 8, rebuildZExtCst},
503         {HasAVX2 ? X86::VPMOVSXWQYrm : 0, 4, 16, rebuildSExtCst},
504         {HasAVX2 ? X86::VPMOVZXWQYrm : 0, 4, 16, rebuildZExtCst},
505         {HasAVX2 ? X86::VBROADCASTI128rm : X86::VBROADCASTF128rm, 1, 128,
506          rebuildSplatCst},
507         {HasAVX2 ? X86::VPMOVSXBWYrm : 0, 16, 8, rebuildSExtCst},
508         {HasAVX2 ? X86::VPMOVZXBWYrm : 0, 16, 8, rebuildZExtCst},
509         {HasAVX2 ? X86::VPMOVSXWDYrm : 0, 8, 16, rebuildSExtCst},
510         {HasAVX2 ? X86::VPMOVZXWDYrm : 0, 8, 16, rebuildZExtCst},
511         {HasAVX2 ? X86::VPMOVSXDQYrm : 0, 4, 32, rebuildSExtCst},
512         {HasAVX2 ? X86::VPMOVZXDQYrm : 0, 4, 32, rebuildZExtCst}};
513     return FixupConstant(Fixups, 256, 1);
514   }
515   case X86::VMOVDQA32Z128rm:
516   case X86::VMOVDQA64Z128rm:
517   case X86::VMOVDQU32Z128rm:
518   case X86::VMOVDQU64Z128rm: {
519     FixupEntry Fixups[] = {
520         {HasBWI ? X86::VPBROADCASTBZ128rm : 0, 1, 8, rebuildSplatCst},
521         {HasBWI ? X86::VPBROADCASTWZ128rm : 0, 1, 16, rebuildSplatCst},
522         {X86::VPMOVSXBQZ128rm, 2, 8, rebuildSExtCst},
523         {X86::VPMOVZXBQZ128rm, 2, 8, rebuildZExtCst},
524         {X86::VMOVDI2PDIZrm, 1, 32, rebuildZeroUpperCst},
525         {X86::VPBROADCASTDZ128rm, 1, 32, rebuildSplatCst},
526         {X86::VPMOVSXBDZ128rm, 4, 8, rebuildSExtCst},
527         {X86::VPMOVZXBDZ128rm, 4, 8, rebuildZExtCst},
528         {X86::VPMOVSXWQZ128rm, 2, 16, rebuildSExtCst},
529         {X86::VPMOVZXWQZ128rm, 2, 16, rebuildZExtCst},
530         {X86::VMOVQI2PQIZrm, 1, 64, rebuildZeroUpperCst},
531         {X86::VPBROADCASTQZ128rm, 1, 64, rebuildSplatCst},
532         {HasBWI ? X86::VPMOVSXBWZ128rm : 0, 8, 8, rebuildSExtCst},
533         {HasBWI ? X86::VPMOVZXBWZ128rm : 0, 8, 8, rebuildZExtCst},
534         {X86::VPMOVSXWDZ128rm, 4, 16, rebuildSExtCst},
535         {X86::VPMOVZXWDZ128rm, 4, 16, rebuildZExtCst},
536         {X86::VPMOVSXDQZ128rm, 2, 32, rebuildSExtCst},
537         {X86::VPMOVZXDQZ128rm, 2, 32, rebuildZExtCst}};
538     return FixupConstant(Fixups, 128, 1);
539   }
540   case X86::VMOVDQA32Z256rm:
541   case X86::VMOVDQA64Z256rm:
542   case X86::VMOVDQU32Z256rm:
543   case X86::VMOVDQU64Z256rm: {
544     FixupEntry Fixups[] = {
545         {HasBWI ? X86::VPBROADCASTBZ256rm : 0, 1, 8, rebuildSplatCst},
546         {HasBWI ? X86::VPBROADCASTWZ256rm : 0, 1, 16, rebuildSplatCst},
547         {X86::VPBROADCASTDZ256rm, 1, 32, rebuildSplatCst},
548         {X86::VPMOVSXBQZ256rm, 4, 8, rebuildSExtCst},
549         {X86::VPMOVZXBQZ256rm, 4, 8, rebuildZExtCst},
550         {X86::VPBROADCASTQZ256rm, 1, 64, rebuildSplatCst},
551         {X86::VPMOVSXBDZ256rm, 8, 8, rebuildSExtCst},
552         {X86::VPMOVZXBDZ256rm, 8, 8, rebuildZExtCst},
553         {X86::VPMOVSXWQZ256rm, 4, 16, rebuildSExtCst},
554         {X86::VPMOVZXWQZ256rm, 4, 16, rebuildZExtCst},
555         {X86::VBROADCASTI32X4Z256rm, 1, 128, rebuildSplatCst},
556         {HasBWI ? X86::VPMOVSXBWZ256rm : 0, 16, 8, rebuildSExtCst},
557         {HasBWI ? X86::VPMOVZXBWZ256rm : 0, 16, 8, rebuildZExtCst},
558         {X86::VPMOVSXWDZ256rm, 8, 16, rebuildSExtCst},
559         {X86::VPMOVZXWDZ256rm, 8, 16, rebuildZExtCst},
560         {X86::VPMOVSXDQZ256rm, 4, 32, rebuildSExtCst},
561         {X86::VPMOVZXDQZ256rm, 4, 32, rebuildZExtCst}};
562     return FixupConstant(Fixups, 256, 1);
563   }
564   case X86::VMOVDQA32Zrm:
565   case X86::VMOVDQA64Zrm:
566   case X86::VMOVDQU32Zrm:
567   case X86::VMOVDQU64Zrm: {
568     FixupEntry Fixups[] = {
569         {HasBWI ? X86::VPBROADCASTBZrm : 0, 1, 8, rebuildSplatCst},
570         {HasBWI ? X86::VPBROADCASTWZrm : 0, 1, 16, rebuildSplatCst},
571         {X86::VPBROADCASTDZrm, 1, 32, rebuildSplatCst},
572         {X86::VPBROADCASTQZrm, 1, 64, rebuildSplatCst},
573         {X86::VPMOVSXBQZrm, 8, 8, rebuildSExtCst},
574         {X86::VPMOVZXBQZrm, 8, 8, rebuildZExtCst},
575         {X86::VBROADCASTI32X4rm, 1, 128, rebuildSplatCst},
576         {X86::VPMOVSXBDZrm, 16, 8, rebuildSExtCst},
577         {X86::VPMOVZXBDZrm, 16, 8, rebuildZExtCst},
578         {X86::VPMOVSXWQZrm, 8, 16, rebuildSExtCst},
579         {X86::VPMOVZXWQZrm, 8, 16, rebuildZExtCst},
580         {X86::VBROADCASTI64X4rm, 1, 256, rebuildSplatCst},
581         {HasBWI ? X86::VPMOVSXBWZrm : 0, 32, 8, rebuildSExtCst},
582         {HasBWI ? X86::VPMOVZXBWZrm : 0, 32, 8, rebuildZExtCst},
583         {X86::VPMOVSXWDZrm, 16, 16, rebuildSExtCst},
584         {X86::VPMOVZXWDZrm, 16, 16, rebuildZExtCst},
585         {X86::VPMOVSXDQZrm, 8, 32, rebuildSExtCst},
586         {X86::VPMOVZXDQZrm, 8, 32, rebuildZExtCst}};
587     return FixupConstant(Fixups, 512, 1);
588   }
589   }
590 
591   auto ConvertToBroadcastAVX512 = [&](unsigned OpSrc32, unsigned OpSrc64) {
592     unsigned OpBcst32 = 0, OpBcst64 = 0;
593     unsigned OpNoBcst32 = 0, OpNoBcst64 = 0;
594     if (OpSrc32) {
595       if (const X86FoldTableEntry *Mem2Bcst =
596               llvm::lookupBroadcastFoldTableBySize(OpSrc32, 32)) {
597         OpBcst32 = Mem2Bcst->DstOp;
598         OpNoBcst32 = Mem2Bcst->Flags & TB_INDEX_MASK;
599       }
600     }
601     if (OpSrc64) {
602       if (const X86FoldTableEntry *Mem2Bcst =
603               llvm::lookupBroadcastFoldTableBySize(OpSrc64, 64)) {
604         OpBcst64 = Mem2Bcst->DstOp;
605         OpNoBcst64 = Mem2Bcst->Flags & TB_INDEX_MASK;
606       }
607     }
608     assert(((OpBcst32 == 0) || (OpBcst64 == 0) || (OpNoBcst32 == OpNoBcst64)) &&
609            "OperandNo mismatch");
610 
611     if (OpBcst32 || OpBcst64) {
612       unsigned OpNo = OpBcst32 == 0 ? OpNoBcst64 : OpNoBcst32;
613       FixupEntry Fixups[] = {{(int)OpBcst32, 32, 32, rebuildSplatCst},
614                              {(int)OpBcst64, 64, 64, rebuildSplatCst}};
615       // TODO: Add support for RegBitWidth, but currently rebuildSplatCst
616       // doesn't require it (defaults to Constant::getPrimitiveSizeInBits).
617       return FixupConstant(Fixups, 0, OpNo);
618     }
619     return false;
620   };
621 
622   // Attempt to find a AVX512 mapping from a full width memory-fold instruction
623   // to a broadcast-fold instruction variant.
624   if ((MI.getDesc().TSFlags & X86II::EncodingMask) == X86II::EVEX)
625     return ConvertToBroadcastAVX512(Opc, Opc);
626 
627   // Reverse the X86InstrInfo::setExecutionDomainCustom EVEX->VEX logic
628   // conversion to see if we can convert to a broadcasted (integer) logic op.
629   if (HasVLX && !HasDQI) {
630     unsigned OpSrc32 = 0, OpSrc64 = 0;
631     switch (Opc) {
632     case X86::VANDPDrm:
633     case X86::VANDPSrm:
634     case X86::VPANDrm:
635       OpSrc32 = X86 ::VPANDDZ128rm;
636       OpSrc64 = X86 ::VPANDQZ128rm;
637       break;
638     case X86::VANDPDYrm:
639     case X86::VANDPSYrm:
640     case X86::VPANDYrm:
641       OpSrc32 = X86 ::VPANDDZ256rm;
642       OpSrc64 = X86 ::VPANDQZ256rm;
643       break;
644     case X86::VANDNPDrm:
645     case X86::VANDNPSrm:
646     case X86::VPANDNrm:
647       OpSrc32 = X86 ::VPANDNDZ128rm;
648       OpSrc64 = X86 ::VPANDNQZ128rm;
649       break;
650     case X86::VANDNPDYrm:
651     case X86::VANDNPSYrm:
652     case X86::VPANDNYrm:
653       OpSrc32 = X86 ::VPANDNDZ256rm;
654       OpSrc64 = X86 ::VPANDNQZ256rm;
655       break;
656     case X86::VORPDrm:
657     case X86::VORPSrm:
658     case X86::VPORrm:
659       OpSrc32 = X86 ::VPORDZ128rm;
660       OpSrc64 = X86 ::VPORQZ128rm;
661       break;
662     case X86::VORPDYrm:
663     case X86::VORPSYrm:
664     case X86::VPORYrm:
665       OpSrc32 = X86 ::VPORDZ256rm;
666       OpSrc64 = X86 ::VPORQZ256rm;
667       break;
668     case X86::VXORPDrm:
669     case X86::VXORPSrm:
670     case X86::VPXORrm:
671       OpSrc32 = X86 ::VPXORDZ128rm;
672       OpSrc64 = X86 ::VPXORQZ128rm;
673       break;
674     case X86::VXORPDYrm:
675     case X86::VXORPSYrm:
676     case X86::VPXORYrm:
677       OpSrc32 = X86 ::VPXORDZ256rm;
678       OpSrc64 = X86 ::VPXORQZ256rm;
679       break;
680     }
681     if (OpSrc32 || OpSrc64)
682       return ConvertToBroadcastAVX512(OpSrc32, OpSrc64);
683   }
684 
685   return false;
686 }
687 
688 bool X86FixupVectorConstantsPass::runOnMachineFunction(MachineFunction &MF) {
689   LLVM_DEBUG(dbgs() << "Start X86FixupVectorConstants\n";);
690   bool Changed = false;
691   ST = &MF.getSubtarget<X86Subtarget>();
692   TII = ST->getInstrInfo();
693   SM = &ST->getSchedModel();
694 
695   for (MachineBasicBlock &MBB : MF) {
696     for (MachineInstr &MI : MBB) {
697       if (processInstruction(MF, MBB, MI)) {
698         ++NumInstChanges;
699         Changed = true;
700       }
701     }
702   }
703   LLVM_DEBUG(dbgs() << "End X86FixupVectorConstants\n";);
704   return Changed;
705 }
706