[PATCH] D108833: [LoopDeletion] Use max trip count to break backedge in addition to exact one

Mon Nov 29 09:06:30 PST 2021

uabelho added a comment.

Hi,

The following starts crashing with this patch:

  opt -passes='function(loop-mssa(licm,loop-rotate,loop-deletion,lnicm))' -o /dev/null bbi-63573.ll

We get

  opt: ../lib/Transforms/Scalar/LICM.cpp:1639: void splitPredecessorsOfLoopExit(llvm::PHINode *, llvm::DominatorTree *, llvm::LoopInfo *, const llvm::Loop *, llvm::LoopSafetyInfo *, llvm::MemorySSAUpdater *): Assertion `CurLoop->contains(PredBB) && "Expect all predecessors are in the loop"' failed.
  PLEASE submit a bug report to https://bugs.llvm.org/ and include the crash backtrace.
  Stack dump:
  0.	Program arguments: ../../master-github/llvm/build-all/bin/opt -passes=function(loop-mssa(licm,loop-rotate,loop-deletion,lnicm)) -o /dev/null bbi-63573.ll
   #0 0x0000000002bc80c3 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (../../master-github/llvm/build-all/bin/opt+0x2bc80c3)
   #1 0x0000000002bc5d3e llvm::sys::RunSignalHandlers() (../../master-github/llvm/build-all/bin/opt+0x2bc5d3e)
   #2 0x0000000002bc8446 SignalHandler(int) Signals.cpp:0:0
   #3 0x00007fe912719630 __restore_rt sigaction.c:0:0
   #4 0x00007fe90fe4c387 raise (/lib64/libc.so.6+0x36387)
   #5 0x00007fe90fe4da78 abort (/lib64/libc.so.6+0x37a78)
   #6 0x00007fe90fe451a6 __assert_fail_base (/lib64/libc.so.6+0x2f1a6)
   #7 0x00007fe90fe45252 (/lib64/libc.so.6+0x2f252)
   #8 0x000000000291ab08 llvm::sinkRegion(llvm::DomTreeNodeBase<llvm::BasicBlock>*, llvm::AAResults*, llvm::LoopInfo*, llvm::DominatorTree*, llvm::BlockFrequencyInfo*, llvm::TargetLibraryInfo*, llvm::TargetTransformInfo*, llvm::Loop*, llvm::MemorySSAUpdater*, llvm::ICFLoopSafetyInfo*, llvm::SinkAndHoistLICMFlags&, llvm::OptimizationRemarkEmitter*, llvm::Loop*) (../../master-github/llvm/build-all/bin/opt+0x291ab08)
   #9 0x000000000291c6f8 llvm::sinkRegionForLoopNest(llvm::DomTreeNodeBase<llvm::BasicBlock>*, llvm::AAResults*, llvm::LoopInfo*, llvm::DominatorTree*, llvm::BlockFrequencyInfo*, llvm::TargetLibraryInfo*, llvm::TargetTransformInfo*, llvm::Loop*, llvm::MemorySSAUpdater*, llvm::ICFLoopSafetyInfo*, llvm::SinkAndHoistLICMFlags&, llvm::OptimizationRemarkEmitter*) (../../master-github/llvm/build-all/bin/opt+0x291c6f8)
  #10 0x000000000291637e (anonymous namespace)::LoopInvariantCodeMotion::runOnLoop(llvm::Loop*, llvm::AAResults*, llvm::LoopInfo*, llvm::DominatorTree*, llvm::BlockFrequencyInfo*, llvm::TargetLibraryInfo*, llvm::TargetTransformInfo*, llvm::ScalarEvolution*, llvm::MemorySSA*, llvm::OptimizationRemarkEmitter*, bool) LICM.cpp:0:0
  #11 0x0000000002917502 llvm::LNICMPass::run(llvm::LoopNest&, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>&, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&) (../../master-github/llvm/build-all/bin/opt+0x2917502)
  #12 0x0000000002ed6b8d llvm::detail::PassModel<llvm::LoopNest, llvm::LNICMPass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>::run(llvm::LoopNest&, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>&, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&) crtstuff.c:0:0
  #13 0x000000000341163c llvm::Optional<llvm::PreservedAnalyses> llvm::PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>::runSinglePass<llvm::LoopNest, std::unique_ptr<llvm::detail::PassConcept<llvm::LoopNest, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>, std::default_delete<llvm::detail::PassConcept<llvm::LoopNest, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&> > > >(llvm::LoopNest&, std::unique_ptr<llvm::detail::PassConcept<llvm::LoopNest, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>, std::default_delete<llvm::detail::PassConcept<llvm::LoopNest, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&> > >&, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>&, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&, llvm::PassInstrumentation&) (../../master-github/llvm/build-all/bin/opt+0x341163c)
  #14 0x0000000003410a83 llvm::PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>::runWithLoopNestPasses(llvm::Loop&, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>&, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&) (../../master-github/llvm/build-all/bin/opt+0x3410a83)
  #15 0x0000000003410661 llvm::PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>::run(llvm::Loop&, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>&, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&) (../../master-github/llvm/build-all/bin/opt+0x3410661)
  #16 0x0000000002eaa25d llvm::detail::PassModel<llvm::Loop, llvm::PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>::run(llvm::Loop&, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>&, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&) crtstuff.c:0:0
  #17 0x000000000341255b llvm::FunctionToLoopPassAdaptor::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../master-github/llvm/build-all/bin/opt+0x341255b)
  #18 0x0000000002ec593d llvm::detail::PassModel<llvm::Function, llvm::FunctionToLoopPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) crtstuff.c:0:0
  #19 0x00000000023562a5 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (../../master-github/llvm/build-all/bin/opt+0x23562a5)
  #20 0x0000000000ae88fd llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function> >, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) crtstuff.c:0:0
  #21 0x000000000235a6ca llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../master-github/llvm/build-all/bin/opt+0x235a6ca)
  #22 0x0000000000793f0d llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module> >::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) crtstuff.c:0:0
  #23 0x00000000023553e8 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module> >::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (../../master-github/llvm/build-all/bin/opt+0x23553e8)
  #24 0x000000000078bc82 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::StringRef>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool) (../../master-github/llvm/build-all/bin/opt+0x78bc82)
  #25 0x000000000079e8ad main (../../master-github/llvm/build-all/bin/opt+0x79e8ad)
  #26 0x00007fe90fe38555 __libc_start_main (/lib64/libc.so.6+0x22555)
  #27 0x00000000007870cc _start (../../master-github/llvm/build-all/bin/opt+0x7870cc)
  Abort

F20789537: bbi-63573.ll <https://reviews.llvm.org/F20789537>

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108833/new/

https://reviews.llvm.org/D108833