diff --git a/llvm/include/llvm/InitializePasses.h b/llvm/include/llvm/InitializePasses.h --- a/llvm/include/llvm/InitializePasses.h +++ b/llvm/include/llvm/InitializePasses.h @@ -91,6 +91,7 @@ void initializeBreakCriticalEdgesPass(PassRegistry&); void initializeBreakFalseDepsPass(PassRegistry&); void initializeCanonicalizeAliasesLegacyPassPass(PassRegistry &); +void initializeCanonicalizeFreezeInLoopsPass(PassRegistry &); void initializeCFGOnlyPrinterLegacyPassPass(PassRegistry&); void initializeCFGOnlyViewerLegacyPassPass(PassRegistry&); void initializeCFGPrinterLegacyPassPass(PassRegistry&); diff --git a/llvm/include/llvm/Transforms/Utils.h b/llvm/include/llvm/Transforms/Utils.h --- a/llvm/include/llvm/Transforms/Utils.h +++ b/llvm/include/llvm/Transforms/Utils.h @@ -154,6 +154,13 @@ // BasicBlock when possible. // FunctionPass *createAssumeSimplifyPass(); + +//===----------------------------------------------------------------------===// +// +// CanonicalizeFreezeInLoops - Canonicalize freeze instructions in loops so they +// don't block SCEV. +// +Pass *createCanonicalizeFreezeInLoopsPass(); } // namespace llvm #endif diff --git a/llvm/include/llvm/Transforms/Utils/CanonicalizeFreezeInLoops.h b/llvm/include/llvm/Transforms/Utils/CanonicalizeFreezeInLoops.h new file mode 100644 --- /dev/null +++ b/llvm/include/llvm/Transforms/Utils/CanonicalizeFreezeInLoops.h @@ -0,0 +1,32 @@ +//==- CanonicalizeFreezeInLoop.h - Canonicalize freezes in a loop-*- C++ -*-==// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file canonicalizes freeze instructions in a loop. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_TRANSFORMS_UTILS_CANONICALIZE_FREEZES_IN_LOOPS_H +#define LLVM_TRANSFORMS_UTILS_CANONICALIZE_FREEZES_IN_LOOPS_H + +#include "llvm/Analysis/LoopInfo.h" +#include "llvm/IR/PassManager.h" +#include "llvm/Transforms/Scalar/LoopPassManager.h" + +namespace llvm { + +/// A pass that canonicalizes freeze instructions in a loop. +class CanonicalizeFreezeInLoopsPass + : public PassInfoMixin { +public: + PreservedAnalyses run(Loop &L, LoopAnalysisManager &AM, + LoopStandardAnalysisResults &AR, LPMUpdater &U); +}; + +} // end namespace llvm + +#endif // LLVM_TRANSFORMS_UTILS_CANONICALIZE_FREEZES_IN_LOOPS_H diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp --- a/llvm/lib/Passes/PassBuilder.cpp +++ b/llvm/lib/Passes/PassBuilder.cpp @@ -179,6 +179,7 @@ #include "llvm/Transforms/Utils/AssumeBundleBuilder.h" #include "llvm/Transforms/Utils/BreakCriticalEdges.h" #include "llvm/Transforms/Utils/CanonicalizeAliases.h" +#include "llvm/Transforms/Utils/CanonicalizeFreezeInLoops.h" #include "llvm/Transforms/Utils/EntryExitInstrumenter.h" #include "llvm/Transforms/Utils/InjectTLIMappings.h" #include "llvm/Transforms/Utils/LCSSA.h" diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def --- a/llvm/lib/Passes/PassRegistry.def +++ b/llvm/lib/Passes/PassRegistry.def @@ -316,6 +316,7 @@ #ifndef LOOP_PASS #define LOOP_PASS(NAME, CREATE_PASS) #endif +LOOP_PASS("canon-freeze", CanonicalizeFreezeInLoopsPass()) LOOP_PASS("invalidate", InvalidateAllAnalysesPass()) LOOP_PASS("licm", LICMPass()) LOOP_PASS("loop-idiom", LoopIdiomRecognizePass()) diff --git a/llvm/lib/Transforms/Utils/CMakeLists.txt b/llvm/lib/Transforms/Utils/CMakeLists.txt --- a/llvm/lib/Transforms/Utils/CMakeLists.txt +++ b/llvm/lib/Transforms/Utils/CMakeLists.txt @@ -10,6 +10,7 @@ CallPromotionUtils.cpp CallGraphUpdater.cpp CanonicalizeAliases.cpp + CanonicalizeFreezeInLoops.cpp CloneFunction.cpp CloneModule.cpp CodeExtractor.cpp diff --git a/llvm/lib/Transforms/Utils/CanonicalizeFreezeInLoops.cpp b/llvm/lib/Transforms/Utils/CanonicalizeFreezeInLoops.cpp new file mode 100644 --- /dev/null +++ b/llvm/lib/Transforms/Utils/CanonicalizeFreezeInLoops.cpp @@ -0,0 +1,247 @@ +//==- CanonicalizeFreezeInLoops - Canonicalize freezes in a loop-*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This pass canonicalizes freeze instructions in a loop by pushing them out to +// the preheader. +// +// loop: +// i = phi init, i.next +// i.next = add nsw i, 1 +// i.next.fr = freeze i.next // push this out of this loop +// use(i.next.fr) +// br i1 (i.next <= N), loop, exit +// => +// init.fr = freeze init +// loop: +// i = phi init.fr, i.next +// i.next = add i, 1 // nsw is dropped here +// use(i.next) +// br i1 (i.next <= N), loop, exit +// +// Removing freezes from these chains help scalar evolution successfully analyze +// expressions. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Transforms/Utils/CanonicalizeFreezeInLoops.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/Analysis/IVUsers.h" +#include "llvm/Analysis/LoopAnalysisManager.h" +#include "llvm/Analysis/LoopInfo.h" +#include "llvm/Analysis/LoopPass.h" +#include "llvm/Analysis/ValueTracking.h" +#include "llvm/InitializePasses.h" +#include "llvm/Pass.h" +#include "llvm/Support/Debug.h" +#include "llvm/Transforms/Utils.h" + +using namespace llvm; + +#define DEBUG_TYPE "canon-freeze" + +namespace { + +class CanonicalizeFreezeInLoops : public LoopPass { +public: + static char ID; + + CanonicalizeFreezeInLoops(); + +private: + bool runOnLoop(Loop *L, LPPassManager &LPM) override; + void getAnalysisUsage(AnalysisUsage &AU) const override; +}; + +class CanonicalizeFreezeInLoopsImpl { + Loop *L; + ScalarEvolution &SE; + DominatorTree &DT; + + struct FrozenIndPHIInfo { + // A freeze instruction that uses an induction phi + FreezeInst *FI = nullptr; + // The induction phi, step instruction, the operand idx of StepInst which is + // a step value + PHINode *PHI; + BinaryOperator *StepInst; + unsigned StepValIdx = 0; + + FrozenIndPHIInfo(PHINode *PHI, BinaryOperator *StepInst) + : PHI(PHI), StepInst(StepInst) {} + }; + + // Can freeze instruction be pushed into operands of I? + // In order to do this, I should not create a poison after I's flags are + // stripped. + bool canHandleInst(const Instruction *I) { + auto Opc = I->getOpcode(); + // If add/sub/mul, drop nsw/nuw flags. + return Opc == Instruction::Add || Opc == Instruction::Sub || + Opc == Instruction::Mul; + } + + void InsertFreezeAndForgetFromSCEV(Use &U); + +public: + CanonicalizeFreezeInLoopsImpl(Loop *L, ScalarEvolution &SE, DominatorTree &DT) + : L(L), SE(SE), DT(DT) {} + bool run(); +}; + +} // anonymous namespace + +// Given U = (value, user), replace value with freeze(value), and let +// SCEV forget user. The inserted freeze is placed in the preheader. +void CanonicalizeFreezeInLoopsImpl::InsertFreezeAndForgetFromSCEV(Use &U) { + auto *PH = L->getLoopPreheader(); + + auto *UserI = cast(U.getUser()); + auto *ValueToFr = U.get(); + assert(L->contains(UserI->getParent()) && + "Should not process an instruction that isn't inside the loop"); + if (isGuaranteedNotToBeUndefOrPoison(ValueToFr, UserI, &DT)) + return; + + LLVM_DEBUG(dbgs() << "canonfr: inserting freeze:\n"); + LLVM_DEBUG(dbgs() << "\tUser: " << *U.getUser() << "\n"); + LLVM_DEBUG(dbgs() << "\tOperand: " << *U.get() << "\n"); + + U.set(new FreezeInst(ValueToFr, ValueToFr->getName() + ".frozen", + PH->getTerminator())); + + SE.forgetValue(UserI); +} + +bool CanonicalizeFreezeInLoopsImpl::run() { + // The loop should be in LoopSimplify form. + if (!L->isLoopSimplifyForm()) + return false; + + SmallVector Candidates; + + for (auto &PHI : L->getHeader()->phis()) { + InductionDescriptor ID; + if (!InductionDescriptor::isInductionPHI(&PHI, L, &SE, ID)) + continue; + + LLVM_DEBUG(dbgs() << "canonfr: PHI: " << PHI << "\n"); + FrozenIndPHIInfo Info(&PHI, ID.getInductionBinOp()); + if (!Info.StepInst || !canHandleInst(Info.StepInst)) { + // The stepping instruction has unknown form. + // Ignore this PHI. + continue; + } + + Info.StepValIdx = Info.StepInst->getOperand(0) == &PHI; + Value *StepV = Info.StepInst->getOperand(Info.StepValIdx); + if (auto *StepI = dyn_cast(StepV)) { + if (L->contains(StepI->getParent())) { + // The step value is inside the loop. Freezing step value will introduce + // another freeze into the loop, so skip this PHI. + continue; + } + } + + auto Visit = [&](User *U) { + if (auto *FI = dyn_cast(U)) { + LLVM_DEBUG(dbgs() << "canonfr: found: " << *FI << "\n"); + Info.FI = FI; + Candidates.push_back(Info); + } + }; + for_each(PHI.users(), Visit); + for_each(Info.StepInst->users(), Visit); + } + + if (Candidates.empty()) + return false; + + SmallSet ProcessedPHIs; + for (const auto &Info : Candidates) { + PHINode *PHI = Info.PHI; + if (!ProcessedPHIs.insert(Info.PHI).second) + continue; + + BinaryOperator *StepI = Info.StepInst; + assert(StepI && "Step instruction should have been found"); + + // Drop flags from the step instruction. + if (!isGuaranteedNotToBeUndefOrPoison(StepI, StepI, &DT)) { + LLVM_DEBUG(dbgs() << "canonfr: drop flags: " << *StepI << "\n"); + StepI->dropPoisonGeneratingFlags(); + SE.forgetValue(StepI); + } + + InsertFreezeAndForgetFromSCEV(StepI->getOperandUse(Info.StepValIdx)); + + unsigned OperandIdx = + PHI->getOperandNumForIncomingValue(PHI->getIncomingValue(0) == StepI); + InsertFreezeAndForgetFromSCEV(PHI->getOperandUse(OperandIdx)); + } + + // Finally, remove the old freeze instructions. + for (const auto &Item : Candidates) { + auto *FI = Item.FI; + LLVM_DEBUG(dbgs() << "canonfr: removing " << *FI << "\n"); + SE.forgetValue(FI); + FI->replaceAllUsesWith(FI->getOperand(0)); + FI->eraseFromParent(); + } + + return true; +} + +CanonicalizeFreezeInLoops::CanonicalizeFreezeInLoops() : LoopPass(ID) { + initializeCanonicalizeFreezeInLoopsPass(*PassRegistry::getPassRegistry()); +} + +void CanonicalizeFreezeInLoops::getAnalysisUsage(AnalysisUsage &AU) const { + AU.addPreservedID(LoopSimplifyID); + AU.addRequired(); + AU.addPreserved(); + AU.addRequiredID(LoopSimplifyID); + AU.addRequired(); + AU.addPreserved(); + AU.addRequired(); + AU.addPreserved(); +} + +bool CanonicalizeFreezeInLoops::runOnLoop(Loop *L, LPPassManager &) { + if (skipLoop(L)) + return false; + + auto &SE = getAnalysis().getSE(); + auto &DT = getAnalysis().getDomTree(); + return CanonicalizeFreezeInLoopsImpl(L, SE, DT).run(); +} + +PreservedAnalyses +CanonicalizeFreezeInLoopsPass::run(Loop &L, LoopAnalysisManager &AM, + LoopStandardAnalysisResults &AR, + LPMUpdater &U) { + if (!CanonicalizeFreezeInLoopsImpl(&L, AR.SE, AR.DT).run()) + return PreservedAnalyses::all(); + + return getLoopPassPreservedAnalyses(); +} + +INITIALIZE_PASS_BEGIN(CanonicalizeFreezeInLoops, "canon-freeze", + "Canonicalize Freeze Instructions in Loops", false, false) +INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) +INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass) +INITIALIZE_PASS_DEPENDENCY(LoopSimplify) +INITIALIZE_PASS_END(CanonicalizeFreezeInLoops, "canon-freeze", + "Canonicalize Freeze Instructions in Loops", false, false) + +Pass *llvm::createCanonicalizeFreezeInLoopsPass() { + return new CanonicalizeFreezeInLoops(); +} + +char CanonicalizeFreezeInLoops::ID = 0; diff --git a/llvm/lib/Transforms/Utils/Utils.cpp b/llvm/lib/Transforms/Utils/Utils.cpp --- a/llvm/lib/Transforms/Utils/Utils.cpp +++ b/llvm/lib/Transforms/Utils/Utils.cpp @@ -27,6 +27,7 @@ initializeAssumeSimplifyPassLegacyPassPass(Registry); initializeBreakCriticalEdgesPass(Registry); initializeCanonicalizeAliasesLegacyPassPass(Registry); + initializeCanonicalizeFreezeInLoopsPass(Registry); initializeInstNamerPass(Registry); initializeLCSSAWrapperPassPass(Registry); initializeLibCallsShrinkWrapLegacyPassPass(Registry); diff --git a/llvm/test/Transforms/CanonicalizeFreezeInLoops/func_from_mcf_r.ll b/llvm/test/Transforms/CanonicalizeFreezeInLoops/func_from_mcf_r.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/CanonicalizeFreezeInLoops/func_from_mcf_r.ll @@ -0,0 +1,71 @@ +; RUN: opt < %s -canon-freeze -S | FileCheck %s +; REQUIRES: aarch64-registered-target +target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128" +target triple = "aarch64-unknown-linux-gnu" + +%struct.arc = type { i32 } +%struct.g = type { i64, %struct.arc, i64, i64, i64 } + +@m = global i64 0 +@h = global %struct.arc* null +@j = global %struct.g zeroinitializer + +define dso_local i32 @main() { +bb: + %tmp = load i64, i64* getelementptr inbounds (%struct.g, %struct.g* @j, i32 0, i32 0), align 8 + %tmp1 = icmp sgt i64 %tmp, 0 + br i1 %tmp1, label %bb2, label %bb35 + +bb2: ; preds = %bb + %tmp3 = load i64, i64* @m, align 8 + %tmp4 = load %struct.arc*, %struct.arc** @h, align 8 +; CHECK: %tmp3.frozen = freeze i64 %tmp3 + br label %bb5 + +bb5: ; preds = %bb28, %bb2 + %tmp6 = phi %struct.arc* [ %tmp4, %bb2 ], [ %tmp31, %bb28 ] + %tmp7 = phi i64 [ %tmp3, %bb2 ], [ %tmp12, %bb28 ] +; CHECK: %tmp7 = phi i64 [ %tmp3.frozen, %bb2 ], [ %tmp12, %bb28 ] + %tmp8 = phi i64 [ 0, %bb2 ], [ %tmp11, %bb28 ] + %tmp9 = trunc i64 %tmp7 to i32 + %tmp10 = getelementptr inbounds %struct.arc, %struct.arc* %tmp6, i64 0, i32 0 + store i32 %tmp9, i32* %tmp10, align 4 + %tmp11 = add nuw nsw i64 %tmp8, 1 + %tmp12 = add nsw i64 %tmp7, 1 +; CHECK: %tmp12 = add i64 %tmp7, 1 + store i64 %tmp12, i64* @m, align 8 + %tmp13 = load i64, i64* inttoptr (i64 16 to i64*), align 16 + %tmp14 = freeze i64 %tmp12 +; CHECK-NOT: %tmp14 = freeze i64 %tmp12 + %tmp15 = freeze i64 %tmp13 + %tmp16 = sdiv i64 %tmp14, %tmp15 + %tmp17 = mul i64 %tmp16, %tmp15 + %tmp18 = sub i64 %tmp14, %tmp17 + %tmp19 = load i64, i64* inttoptr (i64 24 to i64*), align 8 + %tmp20 = icmp sgt i64 %tmp18, %tmp19 + %tmp21 = load i64, i64* inttoptr (i64 32 to i64*), align 32 + br i1 %tmp20, label %bb22, label %bb28 + +bb22: ; preds = %bb5 + %tmp23 = mul nsw i64 %tmp21, %tmp19 + %tmp24 = sub nsw i64 %tmp18, %tmp19 + %tmp25 = add nsw i64 %tmp21, -1 + %tmp26 = mul nsw i64 %tmp25, %tmp24 + %tmp27 = add nsw i64 %tmp26, %tmp23 + br label %bb28 + +bb28: ; preds = %bb22, %bb5 + %tmp29 = phi i64 [ %tmp27, %bb22 ], [ %tmp21, %bb5 ] + %tmp30 = add nsw i64 %tmp29, %tmp16 + %tmp31 = getelementptr inbounds %struct.arc, %struct.arc* getelementptr inbounds (%struct.g, %struct.g* @j, i32 0, i32 1), i64 %tmp30 + store %struct.arc* %tmp31, %struct.arc** @h, align 8 + %tmp32 = load i64, i64* getelementptr inbounds (%struct.g, %struct.g* @j, i32 0, i32 0), align 8 + %tmp33 = icmp slt i64 %tmp11, %tmp32 + br i1 %tmp33, label %bb5, label %bb34 + +bb34: ; preds = %bb28 + br label %bb35 + +bb35: ; preds = %bb34, %bb + ret i32 0 +} diff --git a/llvm/test/Transforms/CanonicalizeFreezeInLoops/nonsteps-preserve-flags.ll b/llvm/test/Transforms/CanonicalizeFreezeInLoops/nonsteps-preserve-flags.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/CanonicalizeFreezeInLoops/nonsteps-preserve-flags.ll @@ -0,0 +1,34 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt < %s -canon-freeze -S | FileCheck %s +declare void @call(i32) + +define void @add(i32 %init, i32 %n) { +; CHECK-LABEL: @add( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: [[NONSTEP:%.*]] = mul nsw i32 [[I]], 2 +; CHECK-NEXT: call void @call(i32 [[NONSTEP]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry], [%i.next, %loop ] + %i.next = add nsw i32 %i, 1 + %i.next.fr = freeze i32 %i.next + %nonstep = mul nsw i32 %i, 2 + call void @call(i32 %nonstep) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} diff --git a/llvm/test/Transforms/CanonicalizeFreezeInLoops/onephi.ll b/llvm/test/Transforms/CanonicalizeFreezeInLoops/onephi.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/CanonicalizeFreezeInLoops/onephi.ll @@ -0,0 +1,547 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt < %s -canon-freeze -S | FileCheck %s +; A set of tests that have one phi node +declare void @call(i32) +declare i32 @get_step() + +define void @add(i32 %init, i32 %n) { +; CHECK-LABEL: @add( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry], [%i.next, %loop ] + %i.next = add i32 %i, 1 + %i.next.fr = freeze i32 %i.next + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @add_comm(i32 %init, i32 %n) { +; CHECK-LABEL: @add_comm( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 1, [[I]] +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add i32 1, %i + %i.next.fr = freeze i32 %i.next + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @add_multiuses(i32 %init, i32 %n) { +; CHECK-LABEL: @add_multiuses( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @add_multiuses2(i32 %init, i32 %n) { +; CHECK-LABEL: @add_multiuses2( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %i.next.fr2 = freeze i32 %i.next + call void @call(i32 %i.next.fr2) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @add_flags(i32 %init, i32 %n) { +; CHECK-LABEL: @add_flags( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @add_ind(i32 %init, i32 %n) { +; CHECK-LABEL: @add_ind( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: [[I_FR_NEXT:%.*]] = add nuw nsw i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_FR_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_FR_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %i.fr = freeze i32 %i + %i.fr.next = add nuw nsw i32 %i.fr, 1 + call void @call(i32 %i.fr.next) + %cond = icmp eq i32 %i.fr.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +define void @add_ind_frozen(i32 %init, i32 %n) { +; CHECK-LABEL: @add_ind_frozen( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT_FR:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_FR:%.*]] = freeze i32 [[I]] +; CHECK-NEXT: [[I_NEXT_FR]] = add nuw nsw i32 [[I_FR]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT_FR]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT_FR]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [%init, %entry], [%i.next.fr, %loop] + %i.fr = freeze i32 %i + %i.next.fr = add nuw nsw i32 %i.fr, 1 + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @add_flags_not_compared(i32 %init, i32 %n) { +; CHECK-LABEL: @add_flags_not_compared( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +define void @add_flags_not_compared_stepinst(i32 %init, i32 %n) { +; CHECK-LABEL: @add_flags_not_compared_stepinst( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT_FR:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT:%.*]] = add nuw nsw i32 [[I]], 1 +; CHECK-NEXT: [[I_NEXT_FR]] = freeze i32 [[I_NEXT]] +; CHECK-NEXT: call void @call(i32 [[I_NEXT_FR]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next.fr, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +; If pushing freeze through icmp is needed, this should be enabled. +; There is no correctness issue in pushing freeze into icmp here, just it's +; being conservative right now. +define void @add_flags_stepinst_frozen(i32 %init, i32 %n) { +; CHECK-LABEL: @add_flags_stepinst_frozen( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: [[COND_FR:%.*]] = freeze i1 [[COND]] +; CHECK-NEXT: br i1 [[COND_FR]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + call void @call(i32 %i.next) + %cond = icmp eq i32 %i.next, %n + %cond.fr = freeze i1 %cond + br i1 %cond.fr, label %loop, label %exit + +exit: + ret void +} + +define void @sub(i32 %init, i32 %n) { +; CHECK-LABEL: @sub( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = sub i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [%init, %entry], [%i.next, %loop] + %i.next = sub nuw nsw i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @init_const(i32 %n) { +; CHECK-LABEL: @init_const( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ 0, %entry ], [ %i.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @step_init_arg(i32 %init, i32 %n, i32 %step) { +; CHECK-LABEL: @step_init_arg( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[STEP_FROZEN:%.*]] = freeze i32 [[STEP:%.*]] +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], [[STEP_FROZEN]] +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [%init, %entry], [%i.next, %loop] + %i.next = add nuw nsw i32 %i, %step + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @step_init_arg_multiuses(i32 %init, i32 %n, i32 %step) { +; CHECK-LABEL: @step_init_arg_multiuses( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[STEP_FROZEN:%.*]] = freeze i32 [[STEP:%.*]] +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], [[STEP_FROZEN]] +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.next = add nsw nuw i32 %i, %step + %i.next.fr1 = freeze i32 %i.next + call void @call(i32 %i.next.fr1) + %i.next.fr2 = freeze i32 %i.next + call void @call(i32 %i.next.fr2) + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @step_init_arg_multiuses2(i32 %init, i32 %n, i32 %step) { +; CHECK-LABEL: @step_init_arg_multiuses2( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[STEP_FROZEN:%.*]] = freeze i32 [[STEP:%.*]] +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: call void @call(i32 [[I]]) +; CHECK-NEXT: call void @call(i32 [[I]]) +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], [[STEP_FROZEN]] +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %init, %entry ], [ %i.next, %loop ] + %i.fr1 = freeze i32 %i + call void @call(i32 %i.fr1) + %i.fr2 = freeze i32 %i + call void @call(i32 %i.fr2) + %i.next = add nsw nuw i32 %i, %step + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +define void @step_init_inst(i32 %n) { +; CHECK-LABEL: @step_init_inst( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[STEP:%.*]] = call i32 @get_step() +; CHECK-NEXT: [[INIT:%.*]] = call i32 @get_step() +; CHECK-NEXT: [[STEP_FROZEN:%.*]] = freeze i32 [[STEP]] +; CHECK-NEXT: [[INIT_FROZEN:%.*]] = freeze i32 [[INIT]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], [[STEP_FROZEN]] +; CHECK-NEXT: call void @call(i32 [[I_NEXT]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + %step = call i32 @get_step() + %init = call i32 @get_step() + br label %loop + +loop: + %i = phi i32 [%init, %entry], [%i.next, %loop] + %i.next = add nuw nsw i32 %i, %step + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +define void @step_inst(i32 %init, i32 %n) { +; CHECK-LABEL: @step_inst( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], [[I]] +; CHECK-NEXT: [[I_NEXT_FR:%.*]] = freeze i32 [[I_NEXT]] +; CHECK-NEXT: call void @call(i32 [[I_NEXT_FR]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT_FR]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [%init, %entry], [%i.next, %loop] + %i.next = add nuw nsw i32 %i, %i + %i.next.fr = freeze i32 %i.next + call void @call(i32 %i.next.fr) + %cond = icmp eq i32 %i.next.fr, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +define void @gep(i8* %init, i8* %end) { +; CHECK-LABEL: @gep( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i8* [ [[INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = getelementptr inbounds i8, i8* [[I]], i64 1 +; CHECK-NEXT: [[I_NEXT_FR:%.*]] = freeze i8* [[I_NEXT]] +; CHECK-NEXT: [[COND:%.*]] = icmp eq i8* [[I_NEXT_FR]], [[END:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i8* [ %init, %entry], [%i.next, %loop ] + %i.next = getelementptr inbounds i8, i8* %i, i64 1 + %i.next.fr = freeze i8* %i.next + %cond = icmp eq i8* %i.next.fr, %end + br i1 %cond, label %loop, label %exit + +exit: + ret void +} diff --git a/llvm/test/Transforms/CanonicalizeFreezeInLoops/phis.ll b/llvm/test/Transforms/CanonicalizeFreezeInLoops/phis.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/CanonicalizeFreezeInLoops/phis.ll @@ -0,0 +1,114 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt < %s -canon-freeze -S | FileCheck %s +; A set of tests that have several phi nodes +declare void @call(i32) +declare i32 @call2() + +define void @onephi_used(i32 %n, i32 %i.init, i32 %j.init) { +; CHECK-LABEL: @onephi_used( +; CHECK-NEXT: entry: +; CHECK-NEXT: [[I_INIT_FROZEN:%.*]] = freeze i32 [[I_INIT:%.*]] +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_INIT_FROZEN]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[J:%.*]] = phi i32 [ [[J_INIT:%.*]], [[ENTRY]] ], [ [[J_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1 +; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i32 [[J]], -2 +; CHECK-NEXT: call void @call(i32 [[I]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop +loop: + %i = phi i32 [ %i.init, %entry ], [ %i.next, %loop ] + %j = phi i32 [ %j.init, %entry ], [ %j.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %j.next = add nuw nsw i32 %j, -2 + %i.fr = freeze i32 %i + call void @call(i32 %i.fr) + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +define void @twophis_used(i32 %n, i32 %i.init, i32 %j.init) { +; CHECK-LABEL: @twophis_used( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[J:%.*]] = phi i32 [ [[J_INIT:%.*]], [[ENTRY]] ], [ [[J_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], 1 +; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i32 [[J]], -2 +; CHECK-NEXT: [[IJ:%.*]] = add i32 [[I]], [[J]] +; CHECK-NEXT: [[IJ_FR:%.*]] = freeze i32 [[IJ]] +; CHECK-NEXT: call void @call(i32 [[IJ_FR]]) +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop +loop: + %i = phi i32 [ %i.init, %entry ], [ %i.next, %loop ] + %j = phi i32 [ %j.init, %entry ], [ %j.next, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %j.next = add nuw nsw i32 %j, -2 + %ij = add i32 %i, %j + %ij.fr = freeze i32 %ij + call void @call(i32 %ij.fr) + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +} + +; Negative test +define void @nonindphi_used(i32 %n, i32 %i.init, i32 %j.init, i32 %k.init) { +; CHECK-LABEL: @nonindphi_used( +; CHECK-NEXT: entry: +; CHECK-NEXT: br label [[LOOP:%.*]] +; CHECK: loop: +; CHECK-NEXT: [[I:%.*]] = phi i32 [ [[I_INIT:%.*]], [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[J:%.*]] = phi i32 [ [[J_INIT:%.*]], [[ENTRY]] ], [ [[J_NEXT:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[K:%.*]] = phi i32 [ [[K_INIT:%.*]], [[ENTRY]] ], [ [[ANY:%.*]], [[LOOP]] ] +; CHECK-NEXT: [[I_NEXT]] = add nuw nsw i32 [[I]], 1 +; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i32 [[J]], -2 +; CHECK-NEXT: [[IJ:%.*]] = add i32 [[I]], [[J]] +; CHECK-NEXT: [[IJK:%.*]] = add i32 [[IJ]], [[K]] +; CHECK-NEXT: [[IJK_FR:%.*]] = freeze i32 [[IJK]] +; CHECK-NEXT: call void @call(i32 [[IJK_FR]]) +; CHECK-NEXT: [[ANY]] = call i32 @call2() +; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 [[I_NEXT]], [[N:%.*]] +; CHECK-NEXT: br i1 [[COND]], label [[LOOP]], label [[EXIT:%.*]] +; CHECK: exit: +; CHECK-NEXT: ret void +; +entry: + br label %loop + +loop: + %i = phi i32 [ %i.init, %entry ], [ %i.next, %loop ] + %j = phi i32 [ %j.init, %entry ], [ %j.next, %loop ] + %k = phi i32 [ %k.init, %entry ], [ %any, %loop ] + %i.next = add nuw nsw i32 %i, 1 + %j.next = add nuw nsw i32 %j, -2 + %ij = add i32 %i, %j + %ijk = add i32 %ij, %k + %ijk.fr = freeze i32 %ijk + call void @call(i32 %ijk.fr) + %any = call i32 @call2() + %cond = icmp eq i32 %i.next, %n + br i1 %cond, label %loop, label %exit + +exit: + ret void +}