On Mar 3, 2026, at 03:45, Ram Ramachandra artagnon@tenstorrent.com wrote:

ci_notify@linaro.org wrote:

...

In tcwg_flang_test/main-aarch64-O3-neoverse_v1-sve_vla-mpipeliner-stack_arrays, after: | commit llvmorg-23-init-5513-gbd5f9384d831 | Author: Ramkumar Ramachandra artagnon@tenstorrent.com | Date: Thu Feb 26 14:50:25 2026 +0000 | | [VPlan] Extend interleave-group-narrowing to WidenCast (#183204) | | WidenCast is very similar to Widen recipes. | | Fixes #128062.

Produces 11 regressions: | | regressions.sum: | Running test-suite:Fujitsu/C/0104 ... | NOEXE: test-suite :: Fujitsu/C/0104/Fujitsu-C-0104_0481.test | NOEXE: test-suite :: Fujitsu/C/0104/Fujitsu-C-0104_0483.test | NOEXE: test-suite :: Fujitsu/C/0104/Fujitsu-C-0104_0485.test | NOEXE: test-suite :: Fujitsu/C/0104/Fujitsu-C-0104_0487.test | ... and 8 more

The NOEXE makes me question if the failure is real: did the compiler crash during compilation?

Hi Ram,

Yes, the compiler crashed when compiling the above tests after your patch, and it didn't crash on the same tests just before your patch.

Specifically, the clang seems to be hitting an assert in performVSelectCombine():

/home/tcwg-buildslave/workspace/tcwg_llvm_0/test/sandbox/build/tools/timeit --summary Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o.time /home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin2/clang -DNDEBUG -O3 -mcpu=neoverse-v1 -msve-vector-bits=scalable -mllvm -scalable-vectorization=preferred -mllvm -aarch64-enable-pipeliner -mllvm -pipeliner-mve-cg -DNDEBUG -MD -MT Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o -MF Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o.d -o Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o -c /home/tcwg-buildslave/workspace/tcwg_llvm_0/test/test-suite/Fujitsu/C/0104/0104_0485.c clang: /home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:27720: SDValue performSelectCombine(SDNode *, TargetLowering::DAGCombinerInfo &): Assertion `DCI.isBeforeLegalize() || DAG.getTargetLoweringInfo().isTypeLegal(SrcVT)' failed. PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script. Stack dump: 0. Program arguments: /home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang -DNDEBUG -O3 -mcpu=neoverse-v1 -msve-vector-bits=scalable -mllvm -scalable-vectorization=preferred -mllvm -aarch64-enable-pipeliner -mllvm -pipeliner-mve-cg -DNDEBUG -MD -MT Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o -MF Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o.d -o Fujitsu/C/0104/CMakeFiles/Fujitsu-C-0104_0485.dir/0104_0485.c.o -c /home/tcwg-buildslave/workspace/tcwg_llvm_0/test/test-suite/Fujitsu/C/0104/0104_0485.c

1. <eof> parser at end of file
2. Code generation
3. Running pass 'Function Pass Manager' on module '/home/tcwg-buildslave/workspace/tcwg_llvm_0/test/test-suite/Fujitsu/C/0104/0104_0485.c'.
4. Running pass 'AArch64 Instruction Selection' on function '@test'

#0 0x0000c11bea79ca98 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x1f6ca98) #1 0x0000c11bea799ef8 llvm::sys::RunSignalHandlers() (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x1f69ef8) #2 0x0000c11bea705108 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0 #3 0x0000ec496bedb968 (linux-vdso.so.1+0x968) #4 0x0000ec496b9a7608 __pthread_kill_implementation ./nptl/pthread_kill.c:44:76 #5 0x0000ec496b95cb3c raise ./signal/../sysdeps/posix/raise.c:27:6 #6 0x0000ec496b947e00 abort ./stdlib/abort.c:81:7 #7 0x0000ec496b955cc0 __assert_fail_base ./assert/assert.c:93:7 #8 0x0000ec496b955d30 __assert_perror_fail ./assert/assert-perr.c:31:1 #9 0x0000c11be97c88e4 performVSelectCombine(llvm::SDNode*, llvm::SelectionDAG&) AArch64ISelLowering.cpp:0:0 #10 0x0000c11be97b9eb4 llvm::AArch64TargetLowering::PerformDAGCombine(llvm::SDNode*, llvm::TargetLowering::DAGCombinerInfo&) const (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0xf89eb4) #11 0x0000c11beb8186bc (anonymous namespace)::DAGCombiner::combine(llvm::SDNode*) DAGCombiner.cpp:0:0 #12 0x0000c11beb816cdc llvm::SelectionDAG::Combine(llvm::CombineLevel, llvm::BatchAAResults*, llvm::CodeGenOptLevel) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x2fe6cdc) #13 0x0000c11beb9c1c54 llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x3191c54) #14 0x0000c11beb9c083c llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x319083c) #15 0x0000c11beb9bdb58 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x318db58) #16 0x0000c11beb9bb3f4 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x318b3f4) #17 0x0000c11be9cc22f4 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x14922f4) #18 0x0000c11bea2a075c llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x1a7075c) #19 0x0000c11bea2a8154 llvm::FPPassManager::runOnModule(llvm::Module&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x1a78154) #20 0x0000c11bea2a10d4 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x1a710d4) #21 0x0000c11beaaef2b4 clang::emitBackendOutput(clang::CompilerInstance&, clang::CodeGenOptions&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtrllvm::vfs::FileSystem, std::unique_ptr<llvm::raw_pwrite_stream, std::default_deletellvm::raw_pwrite_stream>, clang::BackendConsumer*) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x22bf2b4) #22 0x0000c11beb0150f0 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x27e50f0) #23 0x0000c11bec6091d0 clang::ParseAST(clang::Sema&, bool, bool) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x3dd91d0) #24 0x0000c11beb27fab0 clang::FrontendAction::Execute() (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x2a4fab0) #25 0x0000c11beb1fcd28 clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x29ccd28) #26 0x0000c11beb3639e0 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x2b339e0) #27 0x0000c11be953bf28 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0xd0bf28) #28 0x0000c11be95387c4 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&, llvm::IntrusiveRefCntPtrllvm::vfs::FileSystem) driver.cpp:0:0 #29 0x0000c11be953a79c int llvm::function_ref<int (llvm::SmallVectorImpl<char const*>&)>::callback_fn<clang_main(int, char**, llvm::ToolContext const&)::$_0>(long, llvm::SmallVectorImpl<char const*>&) driver.cpp:0:0 #30 0x0000c11beb0757c0 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optionalllvm::StringRef>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::$_0>(long) Job.cpp:0:0 #31 0x0000c11bea704e04 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x1ed4e04) #32 0x0000c11beb074d74 clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optionalllvm::StringRef>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x2844d74) #33 0x0000c11beb03c3ec clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x280c3ec) #34 0x0000c11beb03c5dc clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x280c5dc) #35 0x0000c11beb056800 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0x2826800) #36 0x0000c11be9537c10 clang_main(int, char**, llvm::ToolContext const&) (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0xd07c10) #37 0x0000c11be95469c8 main (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0xd169c8) #38 0x0000ec496b9484c4 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3 #39 0x0000ec496b948598 call_init ./csu/../csu/libc-start.c:128:20 #40 0x0000ec496b948598 __libc_start_main ./csu/../csu/libc-start.c:347:5 #41 0x0000c11be95361f0 _start (/home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin/clang+0xd061f0) clang: error: clang frontend command failed due to signal (use -v to see invocation) clang version 23.0.0git (https://github.com/llvm/llvm-project.git bd5f9384d831c01b5f388de0be910c385562ed77) Target: aarch64-unknown-linux-gnu Thread model: posix InstalledDir: /home/tcwg-buildslave/workspace/tcwg_llvm_0/llvm-install/bin Build config: +assertions clang: note: diagnostic msg:

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PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT: Preprocessed source(s) and associated run script(s) are located at: clang: note: diagnostic msg: /tmp/0104_0485-65a8ee.c clang: note: diagnostic msg: /tmp/0104_0485-65a8ee.sh clang: note: diagnostic msg:

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timeout: the monitored command dumped core

You can see full details in https://ci.linaro.org/job/tcwg_flang_test--main-aarch64-O3-neoverse_v1-sve_v... .

Kind regards,

-- Maxim Kuvyrkov https://www.linaro.org

Thanks.

Warm regards, Ram