1//===----- CodeGen/ExpandVectorPredication.cpp - Expand VP intrinsics -----===//
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 implements IR expansion for vector predication intrinsics, allowing
10// targets to enable vector predication until just before codegen.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/CodeGen/ExpandVectorPredication.h"
15#include "llvm/ADT/Statistic.h"
16#include "llvm/Analysis/TargetTransformInfo.h"
17#include "llvm/Analysis/ValueTracking.h"
18#include "llvm/Analysis/VectorUtils.h"
19#include "llvm/IR/Constants.h"
20#include "llvm/IR/Function.h"
21#include "llvm/IR/IRBuilder.h"
22#include "llvm/IR/Instructions.h"
23#include "llvm/IR/IntrinsicInst.h"
24#include "llvm/IR/Intrinsics.h"
25#include "llvm/Support/CommandLine.h"
26#include "llvm/Support/Compiler.h"
27#include "llvm/Support/Debug.h"
28#include "llvm/Transforms/Utils/LoopUtils.h"
29#include <optional>
30
31using namespace llvm;
32
33using VPLegalization = TargetTransformInfo::VPLegalization;
34using VPTransform = TargetTransformInfo::VPLegalization::VPTransform;
35
36// Keep this in sync with TargetTransformInfo::VPLegalization.
37#define VPINTERNAL_VPLEGAL_CASES \
38 VPINTERNAL_CASE(Legal) \
39 VPINTERNAL_CASE(Discard) \
40 VPINTERNAL_CASE(Convert)
41
42#define VPINTERNAL_CASE(X) "|" #X
43
44// Override options.
45static cl::opt<std::string> EVLTransformOverride(
46 "expandvp-override-evl-transform", cl::init(Val: ""), cl::Hidden,
47 cl::desc("Options: <empty>" VPINTERNAL_VPLEGAL_CASES
48 ". If non-empty, ignore "
49 "TargetTransformInfo and "
50 "always use this transformation for the %evl parameter (Used in "
51 "testing)."));
52
53static cl::opt<std::string> MaskTransformOverride(
54 "expandvp-override-mask-transform", cl::init(Val: ""), cl::Hidden,
55 cl::desc("Options: <empty>" VPINTERNAL_VPLEGAL_CASES
56 ". If non-empty, Ignore "
57 "TargetTransformInfo and "
58 "always use this transformation for the %mask parameter (Used in "
59 "testing)."));
60
61#undef VPINTERNAL_CASE
62#define VPINTERNAL_CASE(X) .Case(#X, VPLegalization::X)
63
64static VPTransform parseOverrideOption(const std::string &TextOpt) {
65 return StringSwitch<VPTransform>(TextOpt) VPINTERNAL_VPLEGAL_CASES;
66}
67
68#undef VPINTERNAL_VPLEGAL_CASES
69
70// Whether any override options are set.
71static bool anyExpandVPOverridesSet() {
72 return !EVLTransformOverride.empty() || !MaskTransformOverride.empty();
73}
74
75#define DEBUG_TYPE "expandvp"
76
77STATISTIC(NumFoldedVL, "Number of folded vector length params");
78STATISTIC(NumLoweredVPOps, "Number of folded vector predication operations");
79
80///// Helpers {
81
82/// \returns Whether the vector mask \p MaskVal has all lane bits set.
83static bool isAllTrueMask(Value *MaskVal) {
84 if (Value *SplattedVal = getSplatValue(V: MaskVal))
85 if (auto *ConstValue = dyn_cast<Constant>(Val: SplattedVal))
86 return ConstValue->isAllOnesValue();
87
88 return false;
89}
90
91/// \returns A non-excepting divisor constant for this type.
92static Constant *getSafeDivisor(Type *DivTy) {
93 assert(DivTy->isIntOrIntVectorTy() && "Unsupported divisor type");
94 return ConstantInt::get(Ty: DivTy, V: 1u, IsSigned: false);
95}
96
97/// Transfer operation properties from \p OldVPI to \p NewVal.
98static void transferDecorations(Value &NewVal, VPIntrinsic &VPI) {
99 auto *NewInst = dyn_cast<Instruction>(Val: &NewVal);
100 if (!NewInst || !isa<FPMathOperator>(Val: NewVal))
101 return;
102
103 auto *OldFMOp = dyn_cast<FPMathOperator>(Val: &VPI);
104 if (!OldFMOp)
105 return;
106
107 NewInst->setFastMathFlags(OldFMOp->getFastMathFlags());
108}
109
110/// Transfer all properties from \p OldOp to \p NewOp and replace all uses.
111/// OldVP gets erased.
112static void replaceOperation(Value &NewOp, VPIntrinsic &OldOp) {
113 transferDecorations(NewVal&: NewOp, VPI&: OldOp);
114
115 if (isa<Instruction>(Val: NewOp) && !NewOp.hasName() && OldOp.hasName())
116 NewOp.takeName(V: &OldOp);
117
118 OldOp.replaceAllUsesWith(V: &NewOp);
119 OldOp.eraseFromParent();
120}
121
122static bool maySpeculateLanes(VPIntrinsic &VPI) {
123 // The result of VP reductions depends on the mask and evl.
124 if (isa<VPReductionIntrinsic>(Val: VPI))
125 return false;
126 // Fallback to whether the intrinsic is speculatable.
127 if (auto IntrID = VPI.getFunctionalIntrinsicID())
128 return Intrinsic::getFnAttributes(C&: VPI.getContext(), id: *IntrID)
129 .hasAttribute(Kind: Attribute::AttrKind::Speculatable);
130 if (auto Opc = VPI.getFunctionalOpcode())
131 return isSafeToSpeculativelyExecuteWithOpcode(Opcode: *Opc, Inst: &VPI);
132 return false;
133}
134
135//// } Helpers
136
137namespace {
138
139// Expansion pass state at function scope.
140struct CachingVPExpander {
141 const TargetTransformInfo &TTI;
142
143 /// \returns A bitmask that is true where the lane position is less-than \p
144 /// EVLParam
145 ///
146 /// \p Builder
147 /// Used for instruction creation.
148 /// \p VLParam
149 /// The explicit vector length parameter to test against the lane
150 /// positions.
151 /// \p ElemCount
152 /// Static (potentially scalable) number of vector elements.
153 Value *convertEVLToMask(IRBuilder<> &Builder, Value *EVLParam,
154 ElementCount ElemCount);
155
156 /// If needed, folds the EVL in the mask operand and discards the EVL
157 /// parameter. Returns true if the mask was actually folded.
158 bool foldEVLIntoMask(VPIntrinsic &VPI);
159
160 /// "Remove" the %evl parameter of \p PI by setting it to the static vector
161 /// length of the operation. Returns true if the %evl (if any) was effectively
162 /// changed.
163 bool discardEVLParameter(VPIntrinsic &PI);
164
165 /// Lower this VP binary operator to a unpredicated binary operator.
166 bool expandPredicationInBinaryOperator(IRBuilder<> &Builder, VPIntrinsic &PI);
167
168 /// Lower this VP reduction to a call to an unpredicated reduction intrinsic.
169 bool expandPredicationInReduction(IRBuilder<> &Builder,
170 VPReductionIntrinsic &PI);
171
172 /// Lower this VP memory operation to a non-VP intrinsic.
173 bool expandPredicationInMemoryIntrinsic(IRBuilder<> &Builder,
174 VPIntrinsic &VPI);
175
176 /// Query TTI and expand the vector predication in \p P accordingly.
177 bool expandPredication(VPIntrinsic &PI);
178
179 /// Determine how and whether the VPIntrinsic \p VPI shall be expanded. This
180 /// overrides TTI with the cl::opts listed at the top of this file.
181 VPLegalization getVPLegalizationStrategy(const VPIntrinsic &VPI) const;
182 bool UsingTTIOverrides;
183
184public:
185 CachingVPExpander(const TargetTransformInfo &TTI)
186 : TTI(TTI), UsingTTIOverrides(anyExpandVPOverridesSet()) {}
187
188 /// Expand llvm.vp.* intrinsics as requested by \p TTI.
189 /// Returns the details of the expansion.
190 VPExpansionDetails expandVectorPredication(VPIntrinsic &VPI);
191};
192
193//// CachingVPExpander {
194
195Value *CachingVPExpander::convertEVLToMask(IRBuilder<> &Builder,
196 Value *EVLParam,
197 ElementCount ElemCount) {
198 // TODO add caching
199 // Scalable vector %evl conversion.
200 if (ElemCount.isScalable()) {
201 Type *BoolVecTy = VectorType::get(ElementType: Builder.getInt1Ty(), EC: ElemCount);
202 // `get_active_lane_mask` performs an implicit less-than comparison.
203 Value *ConstZero = Builder.getInt32(C: 0);
204 return Builder.CreateIntrinsic(ID: Intrinsic::get_active_lane_mask,
205 OverloadTypes: {BoolVecTy, EVLParam->getType()},
206 Args: {ConstZero, EVLParam});
207 }
208
209 // Fixed vector %evl conversion.
210 Type *LaneTy = EVLParam->getType();
211 unsigned NumElems = ElemCount.getFixedValue();
212 Value *VLSplat = Builder.CreateVectorSplat(NumElts: NumElems, V: EVLParam);
213 Value *IdxVec = Builder.CreateStepVector(DstType: VectorType::get(ElementType: LaneTy, EC: ElemCount));
214 return Builder.CreateICmp(P: CmpInst::ICMP_ULT, LHS: IdxVec, RHS: VLSplat);
215}
216
217bool CachingVPExpander::expandPredicationInBinaryOperator(IRBuilder<> &Builder,
218 VPIntrinsic &VPI) {
219 assert((maySpeculateLanes(VPI) || VPI.canIgnoreVectorLengthParam()) &&
220 "Implicitly dropping %evl in non-speculatable operator!");
221
222 auto OC = static_cast<Instruction::BinaryOps>(*VPI.getFunctionalOpcode());
223 assert(Instruction::isBinaryOp(OC));
224
225 Value *Op0 = VPI.getOperand(i_nocapture: 0);
226 Value *Op1 = VPI.getOperand(i_nocapture: 1);
227 Value *Mask = VPI.getMaskParam();
228
229 // Blend in safe operands.
230 if (Mask && !isAllTrueMask(MaskVal: Mask)) {
231 switch (OC) {
232 default:
233 // Can safely ignore the predicate.
234 break;
235
236 // Division operators need a safe divisor on masked-off lanes (1).
237 case Instruction::UDiv:
238 case Instruction::SDiv:
239 case Instruction::URem:
240 case Instruction::SRem:
241 // 2nd operand must not be zero.
242 Value *SafeDivisor = getSafeDivisor(DivTy: VPI.getType());
243 Op1 = Builder.CreateSelect(C: Mask, True: Op1, False: SafeDivisor);
244 }
245 }
246
247 Value *NewBinOp = Builder.CreateBinOp(Opc: OC, LHS: Op0, RHS: Op1);
248
249 replaceOperation(NewOp&: *NewBinOp, OldOp&: VPI);
250 return true;
251}
252
253static Value *getNeutralReductionElement(const VPReductionIntrinsic &VPI,
254 Type *EltTy) {
255 Intrinsic::ID RdxID = *VPI.getFunctionalIntrinsicID();
256 return getReductionIdentity(RdxID, Ty: EltTy, FMF: VPI.getFastMathFlagsOrNone());
257}
258
259bool CachingVPExpander::expandPredicationInReduction(
260 IRBuilder<> &Builder, VPReductionIntrinsic &VPI) {
261 assert((maySpeculateLanes(VPI) || VPI.canIgnoreVectorLengthParam()) &&
262 "Implicitly dropping %evl in non-speculatable operator!");
263
264 Value *Mask = VPI.getMaskParam();
265 Value *RedOp = VPI.getOperand(i_nocapture: VPI.getVectorParamPos());
266
267 // Insert neutral element in masked-out positions
268 if (Mask && !isAllTrueMask(MaskVal: Mask)) {
269 auto *NeutralElt = getNeutralReductionElement(VPI, EltTy: VPI.getType());
270 auto *NeutralVector = Builder.CreateVectorSplat(
271 EC: cast<VectorType>(Val: RedOp->getType())->getElementCount(), V: NeutralElt);
272 RedOp = Builder.CreateSelect(C: Mask, True: RedOp, False: NeutralVector);
273 }
274
275 Value *Reduction;
276 Value *Start = VPI.getOperand(i_nocapture: VPI.getStartParamPos());
277
278 switch (VPI.getIntrinsicID()) {
279 default:
280 llvm_unreachable("Impossible reduction kind");
281 case Intrinsic::vp_reduce_add:
282 case Intrinsic::vp_reduce_mul:
283 case Intrinsic::vp_reduce_and:
284 case Intrinsic::vp_reduce_or:
285 case Intrinsic::vp_reduce_xor: {
286 Intrinsic::ID RedID = *VPI.getFunctionalIntrinsicID();
287 unsigned Opc = getArithmeticReductionInstruction(RdxID: RedID);
288 assert(Instruction::isBinaryOp(Opc));
289 Reduction = Builder.CreateUnaryIntrinsic(ID: RedID, Op: RedOp);
290 Reduction =
291 Builder.CreateBinOp(Opc: (Instruction::BinaryOps)Opc, LHS: Reduction, RHS: Start);
292 break;
293 }
294 case Intrinsic::vp_reduce_smax:
295 case Intrinsic::vp_reduce_smin:
296 case Intrinsic::vp_reduce_umax:
297 case Intrinsic::vp_reduce_umin:
298 case Intrinsic::vp_reduce_fmax:
299 case Intrinsic::vp_reduce_fmin:
300 case Intrinsic::vp_reduce_fmaximum:
301 case Intrinsic::vp_reduce_fminimum: {
302 Intrinsic::ID RedID = *VPI.getFunctionalIntrinsicID();
303 Intrinsic::ID ScalarID = getMinMaxReductionIntrinsicOp(RdxID: RedID);
304 Reduction = Builder.CreateUnaryIntrinsic(ID: RedID, Op: RedOp);
305 transferDecorations(NewVal&: *Reduction, VPI);
306 Reduction = Builder.CreateBinaryIntrinsic(ID: ScalarID, LHS: Reduction, RHS: Start);
307 break;
308 }
309 case Intrinsic::vp_reduce_fadd:
310 Reduction = Builder.CreateFAddReduce(Acc: Start, Src: RedOp);
311 break;
312 case Intrinsic::vp_reduce_fmul:
313 Reduction = Builder.CreateFMulReduce(Acc: Start, Src: RedOp);
314 break;
315 }
316
317 replaceOperation(NewOp&: *Reduction, OldOp&: VPI);
318 return true;
319}
320
321bool CachingVPExpander::expandPredicationInMemoryIntrinsic(IRBuilder<> &Builder,
322 VPIntrinsic &VPI) {
323 assert(VPI.canIgnoreVectorLengthParam());
324
325 const auto &DL = VPI.getDataLayout();
326
327 Value *MaskParam = VPI.getMaskParam();
328 Value *PtrParam = VPI.getMemoryPointerParam();
329 Value *DataParam = VPI.getMemoryDataParam();
330 bool IsUnmasked = isAllTrueMask(MaskVal: MaskParam);
331
332 MaybeAlign AlignOpt = VPI.getPointerAlignment();
333
334 Value *NewMemoryInst = nullptr;
335 switch (VPI.getIntrinsicID()) {
336 default:
337 llvm_unreachable("Not a VP memory intrinsic");
338 case Intrinsic::vp_store:
339 if (IsUnmasked) {
340 StoreInst *NewStore =
341 Builder.CreateStore(Val: DataParam, Ptr: PtrParam, /*IsVolatile*/ isVolatile: false);
342 if (AlignOpt.has_value())
343 NewStore->setAlignment(*AlignOpt);
344 NewMemoryInst = NewStore;
345 } else
346 NewMemoryInst = Builder.CreateMaskedStore(
347 Val: DataParam, Ptr: PtrParam, Alignment: AlignOpt.valueOrOne(), Mask: MaskParam);
348
349 break;
350 case Intrinsic::vp_load:
351 if (IsUnmasked) {
352 LoadInst *NewLoad =
353 Builder.CreateLoad(Ty: VPI.getType(), Ptr: PtrParam, /*IsVolatile*/ isVolatile: false);
354 if (AlignOpt.has_value())
355 NewLoad->setAlignment(*AlignOpt);
356 NewMemoryInst = NewLoad;
357 } else
358 NewMemoryInst = Builder.CreateMaskedLoad(
359 Ty: VPI.getType(), Ptr: PtrParam, Alignment: AlignOpt.valueOrOne(), Mask: MaskParam);
360
361 break;
362 case Intrinsic::vp_scatter: {
363 auto *ElementType =
364 cast<VectorType>(Val: DataParam->getType())->getElementType();
365 NewMemoryInst = Builder.CreateMaskedScatter(
366 Val: DataParam, Ptrs: PtrParam,
367 Alignment: AlignOpt.value_or(u: DL.getPrefTypeAlign(Ty: ElementType)), Mask: MaskParam);
368 break;
369 }
370 case Intrinsic::vp_gather: {
371 auto *ElementType = cast<VectorType>(Val: VPI.getType())->getElementType();
372 NewMemoryInst = Builder.CreateMaskedGather(
373 Ty: VPI.getType(), Ptrs: PtrParam,
374 Alignment: AlignOpt.value_or(u: DL.getPrefTypeAlign(Ty: ElementType)), Mask: MaskParam,
375 PassThru: nullptr);
376 break;
377 }
378 }
379
380 assert(NewMemoryInst);
381 replaceOperation(NewOp&: *NewMemoryInst, OldOp&: VPI);
382 return true;
383}
384
385bool CachingVPExpander::discardEVLParameter(VPIntrinsic &VPI) {
386 LLVM_DEBUG(dbgs() << "Discard EVL parameter in " << VPI << "\n");
387
388 if (VPI.canIgnoreVectorLengthParam())
389 return false;
390
391 Value *EVLParam = VPI.getVectorLengthParam();
392 if (!EVLParam)
393 return false;
394
395 ElementCount StaticElemCount = VPI.getStaticVectorLength();
396 Value *MaxEVL = nullptr;
397 Type *Int32Ty = Type::getInt32Ty(C&: VPI.getContext());
398 if (StaticElemCount.isScalable()) {
399 // TODO add caching
400 IRBuilder<> Builder(VPI.getParent(), VPI.getIterator());
401 Value *FactorConst = Builder.getInt32(C: StaticElemCount.getKnownMinValue());
402 Value *VScale = Builder.CreateVScale(Ty: Int32Ty, Name: "vscale");
403 MaxEVL = Builder.CreateNUWMul(LHS: VScale, RHS: FactorConst, Name: "scalable_size");
404 } else {
405 MaxEVL = ConstantInt::get(Ty: Int32Ty, V: StaticElemCount.getFixedValue(), IsSigned: false);
406 }
407 VPI.setVectorLengthParam(MaxEVL);
408 return true;
409}
410
411bool CachingVPExpander::foldEVLIntoMask(VPIntrinsic &VPI) {
412 LLVM_DEBUG(dbgs() << "Folding vlen for " << VPI << '\n');
413
414 IRBuilder<> Builder(&VPI);
415
416 // Ineffective %evl parameter and so nothing to do here.
417 if (VPI.canIgnoreVectorLengthParam())
418 return false;
419
420 // Only VP intrinsics can have an %evl parameter.
421 Value *OldMaskParam = VPI.getMaskParam();
422 if (!OldMaskParam) {
423 assert((VPI.getIntrinsicID() == Intrinsic::vp_merge) &&
424 "Unexpected VP intrinsic without mask operand");
425 OldMaskParam = VPI.getArgOperand(i: 0);
426 }
427
428 Value *OldEVLParam = VPI.getVectorLengthParam();
429 assert(OldMaskParam && "no mask param to fold the vl param into");
430 assert(OldEVLParam && "no EVL param to fold away");
431
432 LLVM_DEBUG(dbgs() << "OLD evl: " << *OldEVLParam << '\n');
433 LLVM_DEBUG(dbgs() << "OLD mask: " << *OldMaskParam << '\n');
434
435 // Convert the %evl predication into vector mask predication.
436 ElementCount ElemCount = VPI.getStaticVectorLength();
437 Value *VLMask = convertEVLToMask(Builder, EVLParam: OldEVLParam, ElemCount);
438 Value *NewMaskParam = Builder.CreateAnd(LHS: VLMask, RHS: OldMaskParam);
439 if (VPI.getIntrinsicID() == Intrinsic::vp_merge)
440 VPI.setArgOperand(i: 0, v: NewMaskParam);
441 else
442 VPI.setMaskParam(NewMaskParam);
443
444 // Drop the %evl parameter.
445 discardEVLParameter(VPI);
446 assert(VPI.canIgnoreVectorLengthParam() &&
447 "transformation did not render the evl param ineffective!");
448
449 // Reassess the modified instruction.
450 return true;
451}
452
453bool CachingVPExpander::expandPredication(VPIntrinsic &VPI) {
454 LLVM_DEBUG(dbgs() << "Lowering to unpredicated op: " << VPI << '\n');
455
456 IRBuilder<> Builder(&VPI);
457
458 // Try lowering to a LLVM instruction first.
459 auto OC = VPI.getFunctionalOpcode();
460
461 if (OC && Instruction::isBinaryOp(Opcode: *OC))
462 return expandPredicationInBinaryOperator(Builder, VPI);
463
464 if (auto *VPRI = dyn_cast<VPReductionIntrinsic>(Val: &VPI))
465 return expandPredicationInReduction(Builder, VPI&: *VPRI);
466
467 switch (VPI.getIntrinsicID()) {
468 default:
469 break;
470 case Intrinsic::vp_merge: {
471 assert(maySpeculateLanes(VPI) || VPI.canIgnoreVectorLengthParam());
472 Value *NewSelectOp = Builder.CreateSelect(
473 C: VPI.getOperand(i_nocapture: 0), True: VPI.getOperand(i_nocapture: 1), False: VPI.getOperand(i_nocapture: 2));
474 replaceOperation(NewOp&: *NewSelectOp, OldOp&: VPI);
475 return NewSelectOp;
476 }
477 case Intrinsic::vp_load:
478 case Intrinsic::vp_store:
479 case Intrinsic::vp_gather:
480 case Intrinsic::vp_scatter:
481 return expandPredicationInMemoryIntrinsic(Builder, VPI);
482 }
483
484 return false;
485}
486
487//// } CachingVPExpander
488
489void sanitizeStrategy(VPIntrinsic &VPI, VPLegalization &LegalizeStrat) {
490 // Operations with speculatable lanes do not strictly need predication.
491 if (maySpeculateLanes(VPI)) {
492 // Converting a speculatable VP intrinsic means dropping %mask and %evl.
493 // No need to expand %evl into the %mask only to ignore that code.
494 if (LegalizeStrat.OpStrategy == VPLegalization::Convert)
495 LegalizeStrat.EVLParamStrategy = VPLegalization::Discard;
496 return;
497 }
498
499 // We have to preserve the predicating effect of %evl for this
500 // non-speculatable VP intrinsic.
501 // 1) Never discard %evl.
502 // 2) If this VP intrinsic will be expanded to non-VP code, make sure that
503 // %evl gets folded into %mask.
504 if ((LegalizeStrat.EVLParamStrategy == VPLegalization::Discard) ||
505 (LegalizeStrat.OpStrategy == VPLegalization::Convert)) {
506 LegalizeStrat.EVLParamStrategy = VPLegalization::Convert;
507 }
508}
509
510VPLegalization
511CachingVPExpander::getVPLegalizationStrategy(const VPIntrinsic &VPI) const {
512 auto VPStrat = TTI.getVPLegalizationStrategy(PI: VPI);
513 if (LLVM_LIKELY(!UsingTTIOverrides)) {
514 // No overrides - we are in production.
515 return VPStrat;
516 }
517
518 // Overrides set - we are in testing, the following does not need to be
519 // efficient.
520 VPStrat.EVLParamStrategy = parseOverrideOption(TextOpt: EVLTransformOverride);
521 VPStrat.OpStrategy = parseOverrideOption(TextOpt: MaskTransformOverride);
522 return VPStrat;
523}
524
525VPExpansionDetails
526CachingVPExpander::expandVectorPredication(VPIntrinsic &VPI) {
527 auto Strategy = getVPLegalizationStrategy(VPI);
528 sanitizeStrategy(VPI, LegalizeStrat&: Strategy);
529
530 VPExpansionDetails Changed = VPExpansionDetails::IntrinsicUnchanged;
531
532 // Transform the EVL parameter.
533 switch (Strategy.EVLParamStrategy) {
534 case VPLegalization::Legal:
535 break;
536 case VPLegalization::Discard:
537 if (discardEVLParameter(VPI))
538 Changed = VPExpansionDetails::IntrinsicUpdated;
539 break;
540 case VPLegalization::Convert:
541 if (foldEVLIntoMask(VPI)) {
542 Changed = VPExpansionDetails::IntrinsicUpdated;
543 ++NumFoldedVL;
544 }
545 break;
546 }
547
548 // Replace with a non-predicated operation.
549 switch (Strategy.OpStrategy) {
550 case VPLegalization::Legal:
551 break;
552 case VPLegalization::Discard:
553 llvm_unreachable("Invalid strategy for operators.");
554 case VPLegalization::Convert:
555 if (expandPredication(VPI)) {
556 ++NumLoweredVPOps;
557 Changed = VPExpansionDetails::IntrinsicReplaced;
558 }
559 break;
560 }
561
562 return Changed;
563}
564} // namespace
565
566VPExpansionDetails
567llvm::expandVectorPredicationIntrinsic(VPIntrinsic &VPI,
568 const TargetTransformInfo &TTI) {
569 return CachingVPExpander(TTI).expandVectorPredication(VPI);
570}
571