fatal error: error in backend: Cannot select: t54: v4f32 = fexp10 t49, ../simde/x86/svml.h:4583:21 @[ ../test/x86/svml.c:15090:21 ]

[Dave-Lowndes]

The above error occurs building the simd-everywhere project.
Hopefully the information you need is recorded here: https://github.com/simd-everywhere/simde/actions/runs/11917581735/job/33213028281?pr=1233#step:8:1067

[llvmbot]

@llvm/issue-subscribers-backend-webassembly

Author: David Lowndes (Dave-Lowndes)

The above error occurs building the simd-everywhere project. Hopefully the information you need is recorded here: https://github.com/simd-everywhere/simde/actions/runs/11917581735/job/33213028281?pr=1233#step:8:1067

[dschuff]

When clang crashes with that message, it also produces a preprocessed source (.i) and shell script file with the reproducer. Would it be possible for you to upload those?

[Dave-Lowndes]

@dschuff
I'm afraid I'm not familiar with the project or where to start looking to find those things. I've just reported this as a courtesy to someone else on that project.

[mr-c]

@Dave-Lowndes Here's a fresh compile and the request files
svml-774938.c.txt
svml-774938.sh.txt

ninja: Entering directory `build'
[1/8] emcc -Itest/x86/svml-emul-c.js.p -Itest/x86 -I../test/x86 -I. -I.. -Xclang -fcolor-diagnostics -pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -std=c99 -O2 -g -Weverything -fno-lax-vector-conversions -Werror -O2 -msimd128 -Wno-unsafe-buffer-usage -Wno-switch-default -fopenmp-simd -DSIMDE_CONSTRAINED_COMPILATION -DSIMDE_ENABLE_OPENMP -Wno-psabi -DSIMDE_TEST_BARE -DSIMDE_NO_NATIVE -MD -MQ test/x86/svml-emul-c.js.p/svml.c.o -MF test/x86/svml-emul-c.js.p/svml.c.o.d -o test/x86/svml-emul-c.js.p/svml.c.o -c ../test/x86/svml.c
FAILED: test/x86/svml-emul-c.js.p/svml.c.o 
emcc -Itest/x86/svml-emul-c.js.p -Itest/x86 -I../test/x86 -I. -I.. -Xclang -fcolor-diagnostics -pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -std=c99 -O2 -g -Weverything -fno-lax-vector-conversions -Werror -O2 -msimd128 -Wno-unsafe-buffer-usage -Wno-switch-default -fopenmp-simd -DSIMDE_CONSTRAINED_COMPILATION -DSIMDE_ENABLE_OPENMP -Wno-psabi -DSIMDE_TEST_BARE -DSIMDE_NO_NATIVE -MD -MQ test/x86/svml-emul-c.js.p/svml.c.o -MF test/x86/svml-emul-c.js.p/svml.c.o.d -o test/x86/svml-emul-c.js.p/svml.c.o -c ../test/x86/svml.c
fatal error: error in backend: Cannot select: t54: v4f32 = fexp10 t49, ../simde/x86/svml.h:4583:21 @[ ../test/x86/svml.c:15090:21 ]
  t49: v4f32,ch = load<(invariant load (s128) from %ir.arrayidx)> t0, t6, undef:i32, ../test/x86/avx512/../../../simde/x86/avx.h:3825:5 @[ ../test/x86/svml.c:15089:21 ]
    t6: i32 = add nuw t5, t87, ../test/x86/svml.c:15089:42
      t5: i32 = shl nuw nsw t3, Constant:i32<6>, ../test/x86/svml.c:15089:42
        t3: i32,ch = CopyFromReg t0, Register:i32 %1, ../test/x86/svml.c:15089:42
          t2: i32 = Register %1
        t4: i32 = Constant<6>
      t87: i32 = WebAssemblyISD::Wrapper TargetGlobalAddress:i32<ptr @test_simde_mm256_exp10_ps.test_vec> 0, ../test/x86/svml.c:15089:42
        t86: i32 = TargetGlobalAddress<ptr @test_simde_mm256_exp10_ps.test_vec> 0, ../test/x86/svml.c:15089:42
    t8: i32 = undef
In function: test_simde_mm256_exp10_ps
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/mi/crusoe/src/emsdk/upstream/bin/clang -target wasm32-unknown-emscripten -fignore-exceptions -mno-bulk-memory -mno-nontrapping-fptoint -mllvm -combiner-global-alias-analysis=false -mllvm -enable-emscripten-sjlj -mllvm -disable-lsr --sysroot=/home/mi/crusoe/src/emsdk/upstream/emscripten/cache/sysroot -DEMSCRIPTEN -Werror=implicit-function-declaration -Xclang -iwithsysroot/include/fakesdl -Xclang -iwithsysroot/include/compat -Itest/x86/svml-emul-c.js.p -Itest/x86 -I../test/x86 -I. -I.. -Xclang -fcolor-diagnostics -pipe -D_FILE_OFFSET_BITS=64 -Wall -Winvalid-pch -std=c99 -O2 -g3 -Weverything -fno-lax-vector-conversions -Werror -O2 -msimd128 -Wno-unsafe-buffer-usage -Wno-switch-default -fopenmp-simd -DSIMDE_CONSTRAINED_COMPILATION -DSIMDE_ENABLE_OPENMP -Wno-psabi -DSIMDE_TEST_BARE -DSIMDE_NO_NATIVE -MD -MQ test/x86/svml-emul-c.js.p/svml.c.o -MF test/x86/svml-emul-c.js.p/svml.c.o.d -c ../test/x86/svml.c -o test/x86/svml-emul-c.js.p/svml.c.o
1.	<eof> parser at end of file
2.	Code generation
3.	Running pass 'Function Pass Manager' on module '../test/x86/svml.c'.
4.	Running pass 'WebAssembly Instruction Selection' on function '@test_simde_mm256_exp10_ps'
 #0 0x00007f728be93768 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2272768)
 #1 0x00007f728be911de llvm::sys::RunSignalHandlers() (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x22701de)
 #2 0x00007f728be92aef llvm::sys::CleanupOnSignal(unsigned long) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2271aef)
 #3 0x00007f728bdcb977 (anonymous namespace)::CrashRecoveryContextImpl::HandleCrash(int, unsigned long) CrashRecoveryContext.cpp:0:0
 #4 0x00007f728bdcb90f llvm::CrashRecoveryContext::HandleExit(int) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x21aa90f)
 #5 0x00007f728be8dcc7 llvm::sys::Process::Exit(int, bool) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x226ccc7)
 #6 0x000056186bce4993 (/home/mi/crusoe/src/emsdk/upstream/bin/clang+0x13993)
 #7 0x00007f728bddf363 llvm::report_fatal_error(llvm::Twine const&, bool) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x21be363)
 #8 0x00007f728ca3b5da llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e1a5da)
 #9 0x00007f728ca3a684 llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e19684)
#10 0x00007f728e94cd91 (anonymous namespace)::WebAssemblyDAGToDAGISel::Select(llvm::SDNode*) WebAssemblyISelDAGToDAG.cpp:0:0
#11 0x00007f728ca2f9cf llvm::SelectionDAGISel::DoInstructionSelection() (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e0e9cf)
#12 0x00007f728ca2e95f llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e0d95f)
#13 0x00007f728ca2baa0 llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e0aaa0)
#14 0x00007f728ca298f1 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e088f1)
#15 0x00007f728ca27329 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2e06329)
#16 0x00007f728c3e8c57 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x27c7c57)
#17 0x00007f728c05ac6a llvm::FPPassManager::runOnFunction(llvm::Function&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2439c6a)
#18 0x00007f728c063042 llvm::FPPassManager::runOnModule(llvm::Module&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x2442042)
#19 0x00007f728c05b756 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x243a756)
#20 0x00007f7291ccaf18 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::__2::unique_ptr<llvm::raw_pwrite_stream, std::__2::default_delete<llvm::raw_pwrite_stream>>, clang::BackendConsumer*) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x2db2f18)
#21 0x00007f729213a5e6 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x32225e6)
#22 0x00007f7290a00ca9 clang::ParseAST(clang::Sema&, bool, bool) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x1ae8ca9)
#23 0x00007f7292884b4f clang::FrontendAction::Execute() (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x396cb4f)
#24 0x00007f729280184d clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x38e984d)
#25 0x00007f729290ed1c clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x39f6d1c)
#26 0x000056186bce44a3 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/home/mi/crusoe/src/emsdk/upstream/bin/clang+0x134a3)
#27 0x000056186bce0b7e ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#28 0x00007f72924bf039 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::__2::optional<llvm::StringRef>>, std::__2::basic_string<char, std::__2::char_traits<char>, std::__2::allocator<char>>*, bool*) const::$_0>(long) Job.cpp:0:0
#29 0x00007f728bdcb8ae llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libLLVM.so.20.0git+0x21aa8ae)
#30 0x00007f72924be783 clang::driver::CC1Command::Execute(llvm::ArrayRef<std::__2::optional<llvm::StringRef>>, std::__2::basic_string<char, std::__2::char_traits<char>, std::__2::allocator<char>>*, bool*) const (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x35a6783)
#31 0x00007f7292486283 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x356e283)
#32 0x00007f72924864de clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::__2::pair<int, clang::driver::Command const*>>&, bool) const (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x356e4de)
#33 0x00007f72924a0c6d clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::__2::pair<int, clang::driver::Command const*>>&) (/home/mi/crusoe/src/emsdk/upstream/bin/../lib/libclang-cpp.so.20.0git+0x3588c6d)
#34 0x000056186bce0278 clang_main(int, char**, llvm::ToolContext const&) (/home/mi/crusoe/src/emsdk/upstream/bin/clang+0xf278)
#35 0x000056186bcee367 main (/home/mi/crusoe/src/emsdk/upstream/bin/clang+0x1d367)
#36 0x00007f728981c24a __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:74:3
#37 0x00007f728981c305 call_init ./csu/../csu/libc-start.c:128:20
#38 0x00007f728981c305 __libc_start_main ./csu/../csu/libc-start.c:347:5
#39 0x000056186bcde88a _start (/home/mi/crusoe/src/emsdk/upstream/bin/clang+0xd88a)
clang: error: clang frontend command failed with exit code 70 (use -v to see invocation)
clang version 20.0.0git (https:/github.com/llvm/llvm-project f84fc44f1a46969817bfd1b38991f7e43a8efe1d)
Target: wasm32-unknown-emscripten
Thread model: posix
InstalledDir: /home/mi/crusoe/src/emsdk/upstream/bin
Build config: +assertions
clang: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang: note: diagnostic msg: 

clang: note: diagnostic msg: /tmp/svml-774938.sh
clang: note: diagnostic msg: 

********************
ninja: build stopped: subcommand failed.
Found runner: /usr/bin/ninja

[mr-c]

On the emscripten side, I git-bisected the failure to when llvm was upgraded d72e711...9c8dab0

[mr-c]

Using that I was able to git bisect llvm to find that dfb60bb (#109662) is the first commit that triggers this fatal error