[llvm] [SLP]Support LShr as base for copyable elements (PR #153393)

[Mikael Holmén via llvm-commits]

mikaelholmen wrote:

> Hi @alexey-bataev
> 
> Another crash here with this patch: `opt -passes=slp-vectorizer bbi-109672.ll -S -o /dev/null`
> 
> Result:
> 
> ```
> opt: ../lib/Transforms/Vectorize/SLPVectorizer.cpp:20853: auto llvm::slpvectorizer::BoUpSLP::BlockScheduling::tryScheduleBundle(ArrayRef<Value *>, BoUpSLP *, const InstructionsState &, const EdgeInfo &)::(anonymous class)::operator()(bool, ScheduleBundle &) const: Assertion `Picked->isReady() && "must be ready to schedule"' failed.
> PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
> Stack dump:
> 0.	Program arguments: build-all/bin/opt -passes=slp-vectorizer bbi-109672.ll -S -o /dev/null
> 1.	Running pass "function(slp-vectorizer)" on module "bbi-109672.ll"
> 2.	Running pass "slp-vectorizer" on function "main"
>  #0 0x0000556b1173f286 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (build-all/bin/opt+0x47ee286)
>  #1 0x0000556b1173c815 llvm::sys::RunSignalHandlers() (build-all/bin/opt+0x47eb815)
>  #2 0x0000556b11740409 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
>  #3 0x00007f448d3bb990 __restore_rt (/lib64/libpthread.so.0+0x12990)
>  #4 0x00007f448ad5b52f raise (/lib64/libc.so.6+0x4e52f)
>  #5 0x00007f448ad2ee65 abort (/lib64/libc.so.6+0x21e65)
>  #6 0x00007f448ad2ed39 _nl_load_domain.cold.0 (/lib64/libc.so.6+0x21d39)
>  #7 0x00007f448ad53e86 (/lib64/libc.so.6+0x46e86)
>  #8 0x0000556b1327ae22 llvm::slpvectorizer::BoUpSLP::BlockScheduling::tryScheduleBundle(llvm::ArrayRef<llvm::Value*>, llvm::slpvectorizer::BoUpSLP*, (anonymous namespace)::InstructionsState const&, llvm::slpvectorizer::BoUpSLP::EdgeInfo const&)::$_1::operator()(bool, llvm::slpvectorizer::BoUpSLP::ScheduleBundle&) const SLPVectorizer.cpp:0:0
>  #9 0x0000556b131df805 llvm::slpvectorizer::BoUpSLP::buildTreeRec(llvm::ArrayRef<llvm::Value*>, unsigned int, llvm::slpvectorizer::BoUpSLP::EdgeInfo const&, unsigned int) (build-all/bin/opt+0x628e805)
> #10 0x0000556b131dcf36 llvm::slpvectorizer::BoUpSLP::buildTreeRec(llvm::ArrayRef<llvm::Value*>, unsigned int, llvm::slpvectorizer::BoUpSLP::EdgeInfo const&, unsigned int) (build-all/bin/opt+0x628bf36)
> #11 0x0000556b131dcb46 llvm::slpvectorizer::BoUpSLP::buildTreeRec(llvm::ArrayRef<llvm::Value*>, unsigned int, llvm::slpvectorizer::BoUpSLP::EdgeInfo const&, unsigned int) (build-all/bin/opt+0x628bb46)
> #12 0x0000556b131fc1ae llvm::slpvectorizer::BoUpSLP::transformNodes() (build-all/bin/opt+0x62ab1ae)
> #13 0x0000556b1328b819 (anonymous namespace)::HorizontalReduction::tryToReduce(llvm::slpvectorizer::BoUpSLP&, llvm::DataLayout const&, llvm::TargetTransformInfo*, llvm::TargetLibraryInfo const&, llvm::AssumptionCache*) SLPVectorizer.cpp:0:0
> #14 0x0000556b1324b367 llvm::SLPVectorizerPass::vectorizeHorReduction(llvm::PHINode*, llvm::Instruction*, llvm::BasicBlock*, llvm::slpvectorizer::BoUpSLP&, llvm::SmallVectorImpl<llvm::WeakTrackingVH>&) (build-all/bin/opt+0x62fa367)
> #15 0x0000556b1324ca02 llvm::SLPVectorizerPass::vectorizeRootInstruction(llvm::PHINode*, llvm::Instruction*, llvm::BasicBlock*, llvm::slpvectorizer::BoUpSLP&) (build-all/bin/opt+0x62fba02)
> #16 0x0000556b13240f9c llvm::SLPVectorizerPass::vectorizeChainsInBlock(llvm::BasicBlock*, llvm::slpvectorizer::BoUpSLP&) (build-all/bin/opt+0x62eff9c)
> #17 0x0000556b1323db86 llvm::SLPVectorizerPass::runImpl(llvm::Function&, llvm::ScalarEvolution*, llvm::TargetTransformInfo*, llvm::TargetLibraryInfo*, llvm::AAResults*, llvm::LoopInfo*, llvm::DominatorTree*, llvm::AssumptionCache*, llvm::DemandedBits*, llvm::OptimizationRemarkEmitter*) (build-all/bin/opt+0x62ecb86)
> #18 0x0000556b1323d0f7 llvm::SLPVectorizerPass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (build-all/bin/opt+0x62ec0f7)
> #19 0x0000556b12c0d63d llvm::detail::PassModel<llvm::Function, llvm::SLPVectorizerPass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) PassBuilderPipelines.cpp:0:0
> #20 0x0000556b119594d5 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (build-all/bin/opt+0x4a084d5)
> #21 0x0000556b12c0977d llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) PassBuilderPipelines.cpp:0:0
> #22 0x0000556b1195e08e llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (build-all/bin/opt+0x4a0d08e)
> #23 0x0000556b12b98e1d llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) NewPMDriver.cpp:0:0
> #24 0x0000556b119581c5 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (build-all/bin/opt+0x4a071c5)
> #25 0x0000556b12b91c64 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool, bool) (build-all/bin/opt+0x5c40c64)
> #26 0x0000556b116e0a78 optMain (build-all/bin/opt+0x478fa78)
> #27 0x00007f448ad477e5 __libc_start_main (/lib64/libc.so.6+0x3a7e5)
> #28 0x0000556b116de4ae _start (build-all/bin/opt+0x478d4ae)
> Abort (core dumped)
> ```
> 
> I've tested against latest trunk [673750f](https://github.com/llvm/llvm-project/commit/673750feea3a5506ec7cc6271596856dcebe88c4) and it still crashes there.
> 
> [bbi-109672.ll.gz](https://github.com/user-attachments/files/21834949/bbi-109672.ll.gz)

Ping @alexey-bataev 

This still happens at latest trunk, c6fbd1222.

https://github.com/llvm/llvm-project/pull/153393