diff --git a/llvm/include/llvm/Analysis/TargetTransformInfo.h b/llvm/include/llvm/Analysis/TargetTransformInfo.h index cf378008e4c7c..2411b2b31d293 100644 --- a/llvm/include/llvm/Analysis/TargetTransformInfo.h +++ b/llvm/include/llvm/Analysis/TargetTransformInfo.h @@ -419,6 +419,12 @@ class TargetTransformInfo { /// this factor, it is very likely to be predicted correctly. BranchProbability getPredictableBranchThreshold() const; + /// Returns estimated penalty of a branch misprediction in latency. Indicates + /// how aggressive the target wants for eliminating unpredictable branches. A + /// zero return value means extra optimization applied to them should be + /// minimal. + InstructionCost getBranchMispredictPenalty() const; + /// Return true if branch divergence exists. /// /// Branch divergence has a significantly negative impact on GPU performance @@ -1832,6 +1838,7 @@ class TargetTransformInfo::Concept { ArrayRef Operands, TargetCostKind CostKind) = 0; virtual BranchProbability getPredictableBranchThreshold() = 0; + virtual InstructionCost getBranchMispredictPenalty() = 0; virtual bool hasBranchDivergence(const Function *F = nullptr) = 0; virtual bool isSourceOfDivergence(const Value *V) = 0; virtual bool isAlwaysUniform(const Value *V) = 0; @@ -2243,6 +2250,9 @@ class TargetTransformInfo::Model final : public TargetTransformInfo::Concept { BranchProbability getPredictableBranchThreshold() override { return Impl.getPredictableBranchThreshold(); } + InstructionCost getBranchMispredictPenalty() override { + return Impl.getBranchMispredictPenalty(); + } bool hasBranchDivergence(const Function *F = nullptr) override { return Impl.hasBranchDivergence(F); } diff --git a/llvm/include/llvm/Analysis/TargetTransformInfoImpl.h b/llvm/include/llvm/Analysis/TargetTransformInfoImpl.h index 47fde08735c0c..00efa474a91b5 100644 --- a/llvm/include/llvm/Analysis/TargetTransformInfoImpl.h +++ b/llvm/include/llvm/Analysis/TargetTransformInfoImpl.h @@ -99,6 +99,8 @@ class TargetTransformInfoImplBase { return BranchProbability(99, 100); } + InstructionCost getBranchMispredictPenalty() const { return 0; } + bool hasBranchDivergence(const Function *F = nullptr) const { return false; } bool isSourceOfDivergence(const Value *V) const { return false; } diff --git a/llvm/include/llvm/Transforms/Utils/SimplifyCFGOptions.h b/llvm/include/llvm/Transforms/Utils/SimplifyCFGOptions.h index 8008fc6e8422d..2ea9d64f03cb6 100644 --- a/llvm/include/llvm/Transforms/Utils/SimplifyCFGOptions.h +++ b/llvm/include/llvm/Transforms/Utils/SimplifyCFGOptions.h @@ -30,6 +30,7 @@ struct SimplifyCFGOptions { bool SinkCommonInsts = false; bool SimplifyCondBranch = true; bool SpeculateBlocks = true; + bool SpeculateUnpredictables = false; AssumptionCache *AC = nullptr; @@ -75,6 +76,10 @@ struct SimplifyCFGOptions { SpeculateBlocks = B; return *this; } + SimplifyCFGOptions &speculateUnpredictables(bool B) { + SpeculateUnpredictables = B; + return *this; + } }; } // namespace llvm diff --git a/llvm/lib/Analysis/TargetTransformInfo.cpp b/llvm/lib/Analysis/TargetTransformInfo.cpp index 693f7a5bb7af5..6a0fa98089ba5 100644 --- a/llvm/lib/Analysis/TargetTransformInfo.cpp +++ b/llvm/lib/Analysis/TargetTransformInfo.cpp @@ -279,6 +279,10 @@ BranchProbability TargetTransformInfo::getPredictableBranchThreshold() const { : TTIImpl->getPredictableBranchThreshold(); } +InstructionCost TargetTransformInfo::getBranchMispredictPenalty() const { + return TTIImpl->getBranchMispredictPenalty(); +} + bool TargetTransformInfo::hasBranchDivergence(const Function *F) const { return TTIImpl->hasBranchDivergence(F); } diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp index a9d3f8ec3a4ec..ade331166f994 100644 --- a/llvm/lib/Passes/PassBuilder.cpp +++ b/llvm/lib/Passes/PassBuilder.cpp @@ -845,6 +845,8 @@ Expected parseSimplifyCFGOptions(StringRef Params) { Result.hoistCommonInsts(Enable); } else if (ParamName == "sink-common-insts") { Result.sinkCommonInsts(Enable); + } else if (ParamName == "speculate-unpredictables") { + Result.speculateUnpredictables(Enable); } else if (Enable && ParamName.consume_front("bonus-inst-threshold=")) { APInt BonusInstThreshold; if (ParamName.getAsInteger(0, BonusInstThreshold)) diff --git a/llvm/lib/Passes/PassBuilderPipelines.cpp b/llvm/lib/Passes/PassBuilderPipelines.cpp index 4fd5ee1946bb7..010f7247d96fd 100644 --- a/llvm/lib/Passes/PassBuilderPipelines.cpp +++ b/llvm/lib/Passes/PassBuilderPipelines.cpp @@ -1505,8 +1505,9 @@ PassBuilder::buildModuleOptimizationPipeline(OptimizationLevel Level, // LoopSink (and other loop passes since the last simplifyCFG) might have // resulted in single-entry-single-exit or empty blocks. Clean up the CFG. - OptimizePM.addPass( - SimplifyCFGPass(SimplifyCFGOptions().convertSwitchRangeToICmp(true))); + OptimizePM.addPass(SimplifyCFGPass(SimplifyCFGOptions() + .convertSwitchRangeToICmp(true) + .speculateUnpredictables(true))); // Add the core optimizing pipeline. MPM.addPass(createModuleToFunctionPassAdaptor(std::move(OptimizePM), @@ -2024,9 +2025,10 @@ PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level, LateFPM.addPass(DivRemPairsPass()); // Delete basic blocks, which optimization passes may have killed. - LateFPM.addPass(SimplifyCFGPass( - SimplifyCFGOptions().convertSwitchRangeToICmp(true).hoistCommonInsts( - true))); + LateFPM.addPass(SimplifyCFGPass(SimplifyCFGOptions() + .convertSwitchRangeToICmp(true) + .hoistCommonInsts(true) + .speculateUnpredictables(true))); MPM.addPass(createModuleToFunctionPassAdaptor(std::move(LateFPM))); // Drop bodies of available eternally objects to improve GlobalDCE. diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp index 32a3683355b72..dc3ac80bdf5cf 100644 --- a/llvm/lib/Target/X86/X86TargetTransformInfo.cpp +++ b/llvm/lib/Target/X86/X86TargetTransformInfo.cpp @@ -6756,3 +6756,8 @@ InstructionCost X86TTIImpl::getScalingFactorCost(Type *Ty, GlobalValue *BaseGV, return AM.Scale != 0; return -1; } + +InstructionCost X86TTIImpl::getBranchMispredictPenalty() const { + // TODO: Hook MispredictPenalty of SchedMachineModel into this. + return 14; +} diff --git a/llvm/lib/Target/X86/X86TargetTransformInfo.h b/llvm/lib/Target/X86/X86TargetTransformInfo.h index 5eccb1aea308d..b619090e8e1e0 100644 --- a/llvm/lib/Target/X86/X86TargetTransformInfo.h +++ b/llvm/lib/Target/X86/X86TargetTransformInfo.h @@ -294,6 +294,8 @@ class X86TTIImpl : public BasicTTIImplBase { bool supportsEfficientVectorElementLoadStore() const; bool enableInterleavedAccessVectorization(); + InstructionCost getBranchMispredictPenalty() const; + private: bool supportsGather() const; InstructionCost getGSVectorCost(unsigned Opcode, TTI::TargetCostKind CostKind, diff --git a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp index b7baf34f27c21..11de37f7a7c10 100644 --- a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp +++ b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp @@ -77,6 +77,9 @@ static cl::opt UserSinkCommonInsts( "sink-common-insts", cl::Hidden, cl::init(false), cl::desc("Sink common instructions (default = false)")); +static cl::opt UserSpeculateUnpredictables( + "speculate-unpredictables", cl::Hidden, cl::init(false), + cl::desc("Speculate unpredictable branches (default = false)")); STATISTIC(NumSimpl, "Number of blocks simplified"); @@ -325,6 +328,8 @@ static void applyCommandLineOverridesToOptions(SimplifyCFGOptions &Options) { Options.HoistCommonInsts = UserHoistCommonInsts; if (UserSinkCommonInsts.getNumOccurrences()) Options.SinkCommonInsts = UserSinkCommonInsts; + if (UserSpeculateUnpredictables.getNumOccurrences()) + Options.SpeculateUnpredictables = UserSpeculateUnpredictables; } SimplifyCFGPass::SimplifyCFGPass() { @@ -351,7 +356,9 @@ void SimplifyCFGPass::printPipeline( OS << (Options.HoistCommonInsts ? "" : "no-") << "hoist-common-insts;"; OS << (Options.SinkCommonInsts ? "" : "no-") << "sink-common-insts;"; OS << (Options.SpeculateBlocks ? "" : "no-") << "speculate-blocks;"; - OS << (Options.SimplifyCondBranch ? "" : "no-") << "simplify-cond-branch"; + OS << (Options.SimplifyCondBranch ? "" : "no-") << "simplify-cond-branch;"; + OS << (Options.SpeculateUnpredictables ? "" : "no-") + << "speculate-unpredictables"; OS << '>'; } diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index 8f717cb43bcb4..f23e28888931d 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -3476,7 +3476,8 @@ static bool FoldCondBranchOnValueKnownInPredecessor(BranchInst *BI, /// Given a BB that starts with the specified two-entry PHI node, /// see if we can eliminate it. static bool FoldTwoEntryPHINode(PHINode *PN, const TargetTransformInfo &TTI, - DomTreeUpdater *DTU, const DataLayout &DL) { + DomTreeUpdater *DTU, const DataLayout &DL, + bool SpeculateUnpredictables) { // Ok, this is a two entry PHI node. Check to see if this is a simple "if // statement", which has a very simple dominance structure. Basically, we // are trying to find the condition that is being branched on, which @@ -3508,7 +3509,8 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetTransformInfo &TTI, // jump to one specific 'then' block (if we have two of them). // It isn't beneficial to speculatively execute the code // from the block that we know is predictably not entered. - if (!DomBI->getMetadata(LLVMContext::MD_unpredictable)) { + bool IsUnpredictable = DomBI->getMetadata(LLVMContext::MD_unpredictable); + if (!IsUnpredictable) { uint64_t TWeight, FWeight; if (extractBranchWeights(*DomBI, TWeight, FWeight) && (TWeight + FWeight) != 0) { @@ -3551,6 +3553,8 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetTransformInfo &TTI, InstructionCost Cost = 0; InstructionCost Budget = TwoEntryPHINodeFoldingThreshold * TargetTransformInfo::TCC_Basic; + if (SpeculateUnpredictables && IsUnpredictable) + Budget += TTI.getBranchMispredictPenalty(); bool Changed = false; for (BasicBlock::iterator II = BB->begin(); isa(II);) { @@ -3620,8 +3624,9 @@ static bool FoldTwoEntryPHINode(PHINode *PN, const TargetTransformInfo &TTI, [](BasicBlock *IfBlock) { return IfBlock->hasAddressTaken(); })) return Changed; - LLVM_DEBUG(dbgs() << "FOUND IF CONDITION! " << *IfCond - << " T: " << IfTrue->getName() + LLVM_DEBUG(dbgs() << "FOUND IF CONDITION! " << *IfCond; + if (IsUnpredictable) dbgs() << " (unpredictable)"; + dbgs() << " T: " << IfTrue->getName() << " F: " << IfFalse->getName() << "\n"); // If we can still promote the PHI nodes after this gauntlet of tests, @@ -7814,7 +7819,8 @@ bool SimplifyCFGOpt::simplifyOnce(BasicBlock *BB) { // eliminate it, do so now. if (auto *PN = dyn_cast(BB->begin())) if (PN->getNumIncomingValues() == 2) - if (FoldTwoEntryPHINode(PN, TTI, DTU, DL)) + if (FoldTwoEntryPHINode(PN, TTI, DTU, DL, + Options.SpeculateUnpredictables)) return true; } diff --git a/llvm/test/Other/new-pm-print-pipeline.ll b/llvm/test/Other/new-pm-print-pipeline.ll index a524c9991f1bf..f2e80814f347a 100644 --- a/llvm/test/Other/new-pm-print-pipeline.ll +++ b/llvm/test/Other/new-pm-print-pipeline.ll @@ -49,8 +49,8 @@ ; RUN: opt -disable-output -disable-verify -print-pipeline-passes -passes='function(print,print)' < %s | FileCheck %s --match-full-lines --check-prefixes=CHECK-17 ; CHECK-17: function(print,print) -; RUN: opt -disable-output -disable-verify -print-pipeline-passes -passes='function(simplifycfg,simplifycfg)' < %s | FileCheck %s --match-full-lines --check-prefixes=CHECK-18 -; CHECK-18: function(simplifycfg,simplifycfg) +; RUN: opt -disable-output -disable-verify -print-pipeline-passes -passes='function(simplifycfg,simplifycfg)' < %s | FileCheck %s --match-full-lines --check-prefixes=CHECK-18 +; CHECK-18: function(simplifycfg,simplifycfg) ; RUN: opt -disable-output -disable-verify -print-pipeline-passes -passes='function(loop-vectorize,loop-vectorize)' < %s | FileCheck %s --match-full-lines --check-prefixes=CHECK-19 ; CHECK-19: function(loop-vectorize,loop-vectorize) diff --git a/llvm/test/Transforms/SimplifyCFG/two-entry-phi-fold-unpredictable.ll b/llvm/test/Transforms/SimplifyCFG/two-entry-phi-fold-unpredictable.ll new file mode 100644 index 0000000000000..82566d47b0328 --- /dev/null +++ b/llvm/test/Transforms/SimplifyCFG/two-entry-phi-fold-unpredictable.ll @@ -0,0 +1,100 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5 +; Two-entry phi nodes with unpredictable conditions may get increased budget for folding. +; RUN: opt < %s -S -passes=simplifycfg | FileCheck --check-prefix=CHECK-NOFOLD %s +; RUN: opt < %s -S -passes='simplifycfg' | FileCheck --check-prefix=CHECK-NOFOLD %s +; RUN: opt -mtriple=x86_64-unknown-linux-gnu -mattr=+avx2 < %s -S -passes=simplifycfg | FileCheck --check-prefix=CHECK-NOFOLD %s +; RUN: opt -mtriple=x86_64-unknown-linux-gnu -mattr=+avx2 < %s -S -passes='simplifycfg' | FileCheck --check-prefix=CHECK-FOLD %s + +define { <2 x float>, <2 x float> } @foo(float %arg, <2 x float> %arg1, <2 x float> %arg2) #0 { +; CHECK-NOFOLD-LABEL: define { <2 x float>, <2 x float> } @foo( +; CHECK-NOFOLD-SAME: float [[ARG:%.*]], <2 x float> [[ARG1:%.*]], <2 x float> [[ARG2:%.*]]) #[[ATTR0:[0-9]+]] { +; CHECK-NOFOLD-NEXT: [[BB:.*]]: +; CHECK-NOFOLD-NEXT: [[I:%.*]] = fcmp fast ogt float [[ARG]], 0x3F747AE140000000 +; CHECK-NOFOLD-NEXT: br i1 [[I]], label %[[BB3:.*]], label %[[BB20:.*]], !unpredictable [[META0:![0-9]+]] +; CHECK-NOFOLD: [[BB3]]: +; CHECK-NOFOLD-NEXT: [[I4:%.*]] = extractelement <2 x float> [[ARG1]], i64 0 +; CHECK-NOFOLD-NEXT: [[I5:%.*]] = fmul fast float [[I4]], [[I4]] +; CHECK-NOFOLD-NEXT: [[I6:%.*]] = extractelement <2 x float> [[ARG1]], i64 1 +; CHECK-NOFOLD-NEXT: [[I7:%.*]] = fmul fast float [[I6]], [[I6]] +; CHECK-NOFOLD-NEXT: [[I8:%.*]] = fadd fast float [[I7]], [[I5]] +; CHECK-NOFOLD-NEXT: [[I9:%.*]] = extractelement <2 x float> [[ARG2]], i64 0 +; CHECK-NOFOLD-NEXT: [[I10:%.*]] = fmul fast float [[I9]], [[I9]] +; CHECK-NOFOLD-NEXT: [[I11:%.*]] = fadd fast float [[I8]], [[I10]] +; CHECK-NOFOLD-NEXT: [[I12:%.*]] = tail call fast noundef float @llvm.sqrt.f32(float [[I11]]) +; CHECK-NOFOLD-NEXT: [[I13:%.*]] = fdiv fast float 0x3FEFD70A40000000, [[I12]] +; CHECK-NOFOLD-NEXT: [[I14:%.*]] = fmul fast float [[I13]], [[I4]] +; CHECK-NOFOLD-NEXT: [[I15:%.*]] = insertelement <2 x float> poison, float [[I14]], i64 0 +; CHECK-NOFOLD-NEXT: [[I16:%.*]] = fmul fast float [[I13]], [[I6]] +; CHECK-NOFOLD-NEXT: [[I17:%.*]] = insertelement <2 x float> [[I15]], float [[I16]], i64 1 +; CHECK-NOFOLD-NEXT: [[I18:%.*]] = fmul fast float [[I13]], [[I9]] +; CHECK-NOFOLD-NEXT: [[I19:%.*]] = insertelement <2 x float> [[ARG2]], float [[I18]], i64 0 +; CHECK-NOFOLD-NEXT: br label %[[BB20]] +; CHECK-NOFOLD: [[BB20]]: +; CHECK-NOFOLD-NEXT: [[I21:%.*]] = phi nsz <2 x float> [ [[I17]], %[[BB3]] ], [ zeroinitializer, %[[BB]] ] +; CHECK-NOFOLD-NEXT: [[I22:%.*]] = phi nsz <2 x float> [ [[I19]], %[[BB3]] ], [ zeroinitializer, %[[BB]] ] +; CHECK-NOFOLD-NEXT: [[I23:%.*]] = insertvalue { <2 x float>, <2 x float> } poison, <2 x float> [[I21]], 0 +; CHECK-NOFOLD-NEXT: [[I24:%.*]] = insertvalue { <2 x float>, <2 x float> } [[I23]], <2 x float> [[I22]], 1 +; CHECK-NOFOLD-NEXT: ret { <2 x float>, <2 x float> } [[I24]] +; +; CHECK-FOLD-LABEL: define { <2 x float>, <2 x float> } @foo( +; CHECK-FOLD-SAME: float [[ARG:%.*]], <2 x float> [[ARG1:%.*]], <2 x float> [[ARG2:%.*]]) #[[ATTR0:[0-9]+]] { +; CHECK-FOLD-NEXT: [[BB:.*:]] +; CHECK-FOLD-NEXT: [[I:%.*]] = fcmp fast ogt float [[ARG]], 0x3F747AE140000000 +; CHECK-FOLD-NEXT: [[I4:%.*]] = extractelement <2 x float> [[ARG1]], i64 0 +; CHECK-FOLD-NEXT: [[I5:%.*]] = fmul fast float [[I4]], [[I4]] +; CHECK-FOLD-NEXT: [[I6:%.*]] = extractelement <2 x float> [[ARG1]], i64 1 +; CHECK-FOLD-NEXT: [[I7:%.*]] = fmul fast float [[I6]], [[I6]] +; CHECK-FOLD-NEXT: [[I8:%.*]] = fadd fast float [[I7]], [[I5]] +; CHECK-FOLD-NEXT: [[I9:%.*]] = extractelement <2 x float> [[ARG2]], i64 0 +; CHECK-FOLD-NEXT: [[I10:%.*]] = fmul fast float [[I9]], [[I9]] +; CHECK-FOLD-NEXT: [[I11:%.*]] = fadd fast float [[I8]], [[I10]] +; CHECK-FOLD-NEXT: [[I12:%.*]] = tail call fast float @llvm.sqrt.f32(float [[I11]]) +; CHECK-FOLD-NEXT: [[I13:%.*]] = fdiv fast float 0x3FEFD70A40000000, [[I12]] +; CHECK-FOLD-NEXT: [[I14:%.*]] = fmul fast float [[I13]], [[I4]] +; CHECK-FOLD-NEXT: [[I15:%.*]] = insertelement <2 x float> poison, float [[I14]], i64 0 +; CHECK-FOLD-NEXT: [[I16:%.*]] = fmul fast float [[I13]], [[I6]] +; CHECK-FOLD-NEXT: [[I17:%.*]] = insertelement <2 x float> [[I15]], float [[I16]], i64 1 +; CHECK-FOLD-NEXT: [[I18:%.*]] = fmul fast float [[I13]], [[I9]] +; CHECK-FOLD-NEXT: [[I19:%.*]] = insertelement <2 x float> [[ARG2]], float [[I18]], i64 0 +; CHECK-FOLD-NEXT: [[I21:%.*]] = select nsz i1 [[I]], <2 x float> [[I17]], <2 x float> zeroinitializer, !unpredictable [[META0:![0-9]+]] +; CHECK-FOLD-NEXT: [[I22:%.*]] = select nsz i1 [[I]], <2 x float> [[I19]], <2 x float> zeroinitializer, !unpredictable [[META0]] +; CHECK-FOLD-NEXT: [[I23:%.*]] = insertvalue { <2 x float>, <2 x float> } poison, <2 x float> [[I21]], 0 +; CHECK-FOLD-NEXT: [[I24:%.*]] = insertvalue { <2 x float>, <2 x float> } [[I23]], <2 x float> [[I22]], 1 +; CHECK-FOLD-NEXT: ret { <2 x float>, <2 x float> } [[I24]] +; +bb: + %i = fcmp fast ogt float %arg, 0x3F747AE140000000 + br i1 %i, label %bb3, label %bb20, !unpredictable !0 + +bb3: ; preds = %bb + %i4 = extractelement <2 x float> %arg1, i64 0 + %i5 = fmul fast float %i4, %i4 + %i6 = extractelement <2 x float> %arg1, i64 1 + %i7 = fmul fast float %i6, %i6 + %i8 = fadd fast float %i7, %i5 + %i9 = extractelement <2 x float> %arg2, i64 0 + %i10 = fmul fast float %i9, %i9 + %i11 = fadd fast float %i8, %i10 + %i12 = tail call fast noundef float @llvm.sqrt.f32(float %i11) + %i13 = fdiv fast float 0x3FEFD70A40000000, %i12 + %i14 = fmul fast float %i13, %i4 + %i15 = insertelement <2 x float> poison, float %i14, i64 0 + %i16 = fmul fast float %i13, %i6 + %i17 = insertelement <2 x float> %i15, float %i16, i64 1 + %i18 = fmul fast float %i13, %i9 + %i19 = insertelement <2 x float> %arg2, float %i18, i64 0 + br label %bb20 + +bb20: ; preds = %bb3, %bb + %i21 = phi nsz <2 x float> [ %i17, %bb3 ], [ zeroinitializer, %bb ] + %i22 = phi nsz <2 x float> [ %i19, %bb3 ], [ zeroinitializer, %bb ] + %i23 = insertvalue { <2 x float>, <2 x float> } poison, <2 x float> %i21, 0 + %i24 = insertvalue { <2 x float>, <2 x float> } %i23, <2 x float> %i22, 1 + ret { <2 x float>, <2 x float> } %i24 +} + +declare float @llvm.sqrt.f32(float) + +attributes #0 = { nounwind } + +!0 = !{}