Author: Roman Lebedev Date: 2020-12-30T23:58:41+03:00 New Revision: 7f221c9196de2f042030e2a31f81089889d705bd
URL: https://github.com/llvm/llvm-project/commit/7f221c9196de2f042030e2a31f81089889d705bd DIFF: https://github.com/llvm/llvm-project/commit/7f221c9196de2f042030e2a31f81089889d705bd.diff LOG: [SimplifyCFG] Teach SwitchToLookupTable() to preserve DomTree Added: Modified: llvm/lib/Transforms/Utils/SimplifyCFG.cpp llvm/test/Transforms/SimplifyCFG/X86/CoveredLookupTable.ll llvm/test/Transforms/SimplifyCFG/X86/disable-lookup-table.ll llvm/test/Transforms/SimplifyCFG/X86/switch-covered-bug.ll llvm/test/Transforms/SimplifyCFG/X86/switch-table-bug.ll llvm/test/Transforms/SimplifyCFG/rangereduce.ll Removed: ################################################################################ diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index 2b631175f55e..7e49d3a1524c 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -5716,7 +5716,7 @@ static void reuseTableCompare( /// successor block with diff erent constant values, replace the switch with /// lookup tables. static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, - const DataLayout &DL, + DomTreeUpdater *DTU, const DataLayout &DL, const TargetTransformInfo &TTI) { assert(SI->getNumCases() > 1 && "Degenerate switch?"); @@ -5814,6 +5814,8 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, if (!ShouldBuildLookupTable(SI, TableSize, TTI, DL, ResultTypes)) return false; + std::vector<DominatorTree::UpdateType> Updates; + // Create the BB that does the lookups. Module &Mod = *CommonDest->getParent()->getParent(); BasicBlock *LookupBB = BasicBlock::Create( @@ -5846,6 +5848,7 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, if (!DefaultIsReachable || GeneratingCoveredLookupTable) { Builder.CreateBr(LookupBB); + Updates.push_back({DominatorTree::Insert, SI->getParent(), LookupBB}); // Note: We call removeProdecessor later since we need to be able to get the // PHI value for the default case in case we're using a bit mask. } else { @@ -5853,6 +5856,9 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, TableIndex, ConstantInt::get(MinCaseVal->getType(), TableSize)); RangeCheckBranch = Builder.CreateCondBr(Cmp, LookupBB, SI->getDefaultDest()); + Updates.push_back({DominatorTree::Insert, SI->getParent(), LookupBB}); + Updates.push_back( + {DominatorTree::Insert, SI->getParent(), SI->getDefaultDest()}); } // Populate the BB that does the lookups. @@ -5890,7 +5896,8 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, Value *LoBit = Builder.CreateTrunc( Shifted, Type::getInt1Ty(Mod.getContext()), "switch.lobit"); Builder.CreateCondBr(LoBit, LookupBB, SI->getDefaultDest()); - + Updates.push_back({DominatorTree::Insert, MaskBB, LookupBB}); + Updates.push_back({DominatorTree::Insert, MaskBB, SI->getDefaultDest()}); Builder.SetInsertPoint(LookupBB); AddPredecessorToBlock(SI->getDefaultDest(), MaskBB, SI->getParent()); } @@ -5900,6 +5907,8 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, // do not delete PHINodes here. SI->getDefaultDest()->removePredecessor(SI->getParent(), /*KeepOneInputPHIs=*/true); + Updates.push_back( + {DominatorTree::Delete, SI->getParent(), SI->getDefaultDest()}); } bool ReturnedEarly = false; @@ -5936,8 +5945,10 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, PHI->addIncoming(Result, LookupBB); } - if (!ReturnedEarly) + if (!ReturnedEarly) { Builder.CreateBr(CommonDest); + Updates.push_back({DominatorTree::Insert, LookupBB, CommonDest}); + } // Remove the switch. for (unsigned i = 0, e = SI->getNumSuccessors(); i < e; ++i) { @@ -5946,8 +5957,11 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder, if (Succ == SI->getDefaultDest()) continue; Succ->removePredecessor(SI->getParent()); + Updates.push_back({DominatorTree::Delete, SI->getParent(), Succ}); } SI->eraseFromParent(); + if (DTU) + DTU->applyUpdatesPermissive(Updates); ++NumLookupTables; if (NeedMask) @@ -6099,7 +6113,7 @@ bool SimplifyCFGOpt::simplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) { // CVP. Therefore, only apply this transformation during late stages of the // optimisation pipeline. if (Options.ConvertSwitchToLookupTable && - SwitchToLookupTable(SI, Builder, DL, TTI)) + SwitchToLookupTable(SI, Builder, DTU, DL, TTI)) return requestResimplify(); if (ReduceSwitchRange(SI, Builder, DL, TTI)) diff --git a/llvm/test/Transforms/SimplifyCFG/X86/CoveredLookupTable.ll b/llvm/test/Transforms/SimplifyCFG/X86/CoveredLookupTable.ll index e3a3b3fc58cd..9bf28fc28390 100644 --- a/llvm/test/Transforms/SimplifyCFG/X86/CoveredLookupTable.ll +++ b/llvm/test/Transforms/SimplifyCFG/X86/CoveredLookupTable.ll @@ -1,5 +1,5 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py -; RUN: opt -simplifycfg -switch-to-lookup -S %s | FileCheck %s +; RUN: opt -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-to-lookup -S %s | FileCheck %s ; RUN: opt -passes='simplify-cfg<switch-to-lookup>' -S %s | FileCheck %s ; rdar://15268442 diff --git a/llvm/test/Transforms/SimplifyCFG/X86/disable-lookup-table.ll b/llvm/test/Transforms/SimplifyCFG/X86/disable-lookup-table.ll index 423d94624333..0d6b823bd88f 100644 --- a/llvm/test/Transforms/SimplifyCFG/X86/disable-lookup-table.ll +++ b/llvm/test/Transforms/SimplifyCFG/X86/disable-lookup-table.ll @@ -1,5 +1,5 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py -; RUN: opt < %s -simplifycfg -switch-to-lookup -S -mtriple=x86_64-unknown-linux-gnu | FileCheck %s +; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-to-lookup -S -mtriple=x86_64-unknown-linux-gnu | FileCheck %s ; RUN: opt < %s -passes='simplify-cfg<switch-to-lookup>' -S -mtriple=x86_64-unknown-linux-gnu | FileCheck %s ; In the presence of "-no-jump-tables"="true", simplifycfg should not convert switches to lookup tables. diff --git a/llvm/test/Transforms/SimplifyCFG/X86/switch-covered-bug.ll b/llvm/test/Transforms/SimplifyCFG/X86/switch-covered-bug.ll index b7bf8054a6f1..6e0639e20e64 100644 --- a/llvm/test/Transforms/SimplifyCFG/X86/switch-covered-bug.ll +++ b/llvm/test/Transforms/SimplifyCFG/X86/switch-covered-bug.ll @@ -1,5 +1,5 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py -; RUN: opt -S -simplifycfg -switch-to-lookup < %s -mtriple=x86_64-apple-darwin12.0.0 | FileCheck %s +; RUN: opt -S -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-to-lookup < %s -mtriple=x86_64-apple-darwin12.0.0 | FileCheck %s ; RUN: opt -S -passes='simplify-cfg<switch-to-lookup>' < %s -mtriple=x86_64-apple-darwin12.0.0 | FileCheck %s ; rdar://17887153 diff --git a/llvm/test/Transforms/SimplifyCFG/X86/switch-table-bug.ll b/llvm/test/Transforms/SimplifyCFG/X86/switch-table-bug.ll index e50a913f9e50..04b8999cc4cc 100644 --- a/llvm/test/Transforms/SimplifyCFG/X86/switch-table-bug.ll +++ b/llvm/test/Transforms/SimplifyCFG/X86/switch-table-bug.ll @@ -1,5 +1,5 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py -; RUN: opt -S -simplifycfg -switch-to-lookup < %s -mtriple=x86_64-apple-darwin12.0.0 | FileCheck %s +; RUN: opt -S -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-to-lookup < %s -mtriple=x86_64-apple-darwin12.0.0 | FileCheck %s ; RUN: opt -S -passes='simplify-cfg<switch-to-lookup>' < %s -mtriple=x86_64-apple-darwin12.0.0 | FileCheck %s ; rdar://17735071 diff --git a/llvm/test/Transforms/SimplifyCFG/rangereduce.ll b/llvm/test/Transforms/SimplifyCFG/rangereduce.ll index 849f55f6f392..c536efd685bb 100644 --- a/llvm/test/Transforms/SimplifyCFG/rangereduce.ll +++ b/llvm/test/Transforms/SimplifyCFG/rangereduce.ll @@ -1,5 +1,5 @@ ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py -; RUN: opt < %s -simplifycfg -switch-to-lookup -S | FileCheck %s +; RUN: opt < %s -simplifycfg -simplifycfg-require-and-preserve-domtree=1 -switch-to-lookup -S | FileCheck %s ; RUN: opt < %s -passes='simplify-cfg<switch-to-lookup>' -S | FileCheck %s target datalayout = "e-n32" _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
