1 //===- VPlanUtils.cpp - VPlan-related utilities ---------------------------===// 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 #include "VPlanUtils.h" 10 #include "VPlanPatternMatch.h" 11 #include "llvm/ADT/TypeSwitch.h" 12 #include "llvm/Analysis/ScalarEvolutionExpressions.h" 13 14 using namespace llvm; 15 16 bool vputils::onlyFirstLaneUsed(const VPValue *Def) { 17 return all_of(Def->users(), 18 [Def](const VPUser *U) { return U->onlyFirstLaneUsed(Def); }); 19 } 20 21 bool vputils::onlyFirstPartUsed(const VPValue *Def) { 22 return all_of(Def->users(), 23 [Def](const VPUser *U) { return U->onlyFirstPartUsed(Def); }); 24 } 25 26 VPValue *vputils::getOrCreateVPValueForSCEVExpr(VPlan &Plan, const SCEV *Expr, 27 ScalarEvolution &SE) { 28 if (auto *Expanded = Plan.getSCEVExpansion(Expr)) 29 return Expanded; 30 VPValue *Expanded = nullptr; 31 if (auto *E = dyn_cast<SCEVConstant>(Expr)) 32 Expanded = Plan.getOrAddLiveIn(E->getValue()); 33 else if (auto *E = dyn_cast<SCEVUnknown>(Expr)) 34 Expanded = Plan.getOrAddLiveIn(E->getValue()); 35 else { 36 Expanded = new VPExpandSCEVRecipe(Expr, SE); 37 Plan.getPreheader()->appendRecipe(Expanded->getDefiningRecipe()); 38 } 39 Plan.addSCEVExpansion(Expr, Expanded); 40 return Expanded; 41 } 42 43 bool vputils::isHeaderMask(const VPValue *V, VPlan &Plan) { 44 if (isa<VPActiveLaneMaskPHIRecipe>(V)) 45 return true; 46 47 auto IsWideCanonicalIV = [](VPValue *A) { 48 return isa<VPWidenCanonicalIVRecipe>(A) || 49 (isa<VPWidenIntOrFpInductionRecipe>(A) && 50 cast<VPWidenIntOrFpInductionRecipe>(A)->isCanonical()); 51 }; 52 53 VPValue *A, *B; 54 using namespace VPlanPatternMatch; 55 56 if (match(V, m_ActiveLaneMask(m_VPValue(A), m_VPValue(B)))) 57 return B == Plan.getTripCount() && 58 (match(A, m_ScalarIVSteps(m_CanonicalIV(), m_SpecificInt(1))) || 59 IsWideCanonicalIV(A)); 60 61 return match(V, m_Binary<Instruction::ICmp>(m_VPValue(A), m_VPValue(B))) && 62 IsWideCanonicalIV(A) && B == Plan.getOrCreateBackedgeTakenCount(); 63 } 64 65 const SCEV *vputils::getSCEVExprForVPValue(VPValue *V, ScalarEvolution &SE) { 66 if (V->isLiveIn()) 67 return SE.getSCEV(V->getLiveInIRValue()); 68 69 // TODO: Support constructing SCEVs for more recipes as needed. 70 return TypeSwitch<const VPRecipeBase *, const SCEV *>(V->getDefiningRecipe()) 71 .Case<VPExpandSCEVRecipe>( 72 [](const VPExpandSCEVRecipe *R) { return R->getSCEV(); }) 73 .Default([&SE](const VPRecipeBase *) { return SE.getCouldNotCompute(); }); 74 } 75