Crash with full LTO when linking Nouveau driver after LLVM commit bbdcba9b851ab #2126
Description
After llvm/llvm-project@bbdcba9, CI sees a crash when building ARCH={arm64,riscv} defconfig + CONFIG_LTO_CLANG_FULL=y:
https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/18308019072/job/52133404579
https://storage.tuxsuite.com/public/clangbuiltlinux/nathan/builds/33jSHeSURyDzaanz5tCXc3IEBzW/build.log
# bad: [7546bd38041612e8b768f4b315e491cd549d608c] [lldb] Add support for unique target ids (#160736)
# good: [572b579632fb79ea6eb562a537c9ff1280b3d4f5] Revert "[InstCombine] Preserve profile after folding select instructions with conditionals" (#161885)
git bisect start '7546bd38041612e8b768f4b315e491cd549d608c' '572b579632fb79ea6eb562a537c9ff1280b3d4f5'
# bad: [44b2673544bf32ae498cfa22193090f9fd7dae24] [CIR] Implement initial LoweringPrepare support for global ctors (#161452)
git bisect bad 44b2673544bf32ae498cfa22193090f9fd7dae24
# good: [795a115d1919966df72079eb3bd82699bfb2fa58] [RegAlloc] Remove default restriction on non-trivial rematerialization (#159211)
git bisect good 795a115d1919966df72079eb3bd82699bfb2fa58
# bad: [38896d67e458cf4d3b5ce0c3742f48e97527c797] [Headers][X86] Add constexpr support for some AVX512 masked extension/truncation intrinsics. (#161984)
git bisect bad 38896d67e458cf4d3b5ce0c3742f48e97527c797
# good: [718ef3427a2ddd09122e2185962e4b241848d8b9] [llvm-c-test] Fix warnings
git bisect good 718ef3427a2ddd09122e2185962e4b241848d8b9
# good: [6b1604ac30082cd7316f06c2b904cb23af95468e] [libc] add IPPROTO related macros (#161855)
git bisect good 6b1604ac30082cd7316f06c2b904cb23af95468e
# bad: [5e92e7f4c0fb9ab92572fb974591d52266be8fc6] [SCCP] Strengthen two-instruction range checks (#162008)
git bisect bad 5e92e7f4c0fb9ab92572fb974591d52266be8fc6
# bad: [bea0225c304e3f8efbca48f8c5ee4b39d8f42e0d] [AMDGPU] Make cluster a target feature (#162040)
git bisect bad bea0225c304e3f8efbca48f8c5ee4b39d8f42e0d
# bad: [bbdcba9b851abe37cf2b10ec6d9b50c12cdd3604] [SimplifyCFG] Fold the contiguous wrapping cases into ICmp. (#161000)
git bisect bad bbdcba9b851abe37cf2b10ec6d9b50c12cdd3604
# good: [36cfdebe927c34508c1e245b459da43b745ae620] [orc-rt] Add method-wrapper utils for use with WrapperFunction::handle. (#162035)
git bisect good 36cfdebe927c34508c1e245b459da43b745ae620
# first bad commit: [bbdcba9b851abe37cf2b10ec6d9b50c12cdd3604] [SimplifyCFG] Fold the contiguous wrapping cases into ICmp. (#161000)
A simplifier reproducer on top of allnoconfig:
$ cat allno.config
CONFIG_DRM=y
CONFIG_DRM_NOUVEAU=y
CONFIG_LTO_CLANG_FULL=y
CONFIG_LTO_NONE=n
CONFIG_PCI=y
$ make -skj"$(nproc)" ARCH=arm64 KCONFIG_ALLCONFIG=1 LLVM=1 clean allnoconfig vmlinux
PHINode should have one entry for each predecessor of its parent basic block!
%100 = phi i32 [ %97, %94 ], [ -38, PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0. Program arguments: ld.lld -EL -maarch64elf -z norelro -mllvm -import-instr-limit=5 -z noexecstack -r -o vmlinux.o -T .tmp_initcalls.lds --whole-archive vmlinux.a --no-whole-archive --start-group --end-group
1. Running pass "verify" on module "ld-temp.o"
#0 0x0000000001e68d2c llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (ld.lld+0x1e68d2c)
#1 0x0000000001e66670 llvm::sys::RunSignalHandlers() (ld.lld+0x1e66670)
#2 0x0000000001e69b54 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
#3 0x0000ffffb67268c0 (linux-vdso.so.1+0x8c0)
#4 0x00000000049f9ed0 llvm::SlotTracker::SlotTracker(llvm::Function const*, bool) (ld.lld+0x49f9ed0)
#5 0x0000000004a11cb0 createSlotTracker(llvm::Value const*) AsmWriter.cpp:0:0
#6 0x0000000004a0f768 writeAsOperandInternal(llvm::raw_ostream&, llvm::Value const*, (anonymous namespace)::AsmWriterContext&, bool) AsmWriter.cpp:0:0
#7 0x0000000004a06448 (anonymous namespace)::AssemblyWriter::printInstruction(llvm::Instruction const&) AsmWriter.cpp:0:0
#8 0x0000000004a04930 llvm::Value::print(llvm::raw_ostream&, llvm::ModuleSlotTracker&, bool) const (ld.lld+0x4a04930)
#9 0x0000000004c1f440 void llvm::VerifierSupport::CheckFailed<llvm::PHINode const*>(llvm::Twine const&, llvm::PHINode const* const&) Verifier.cpp:0:0
#10 0x0000000004bff5dc (anonymous namespace)::Verifier::verify(llvm::Function const&) Verifier.cpp:0:0
#11 0x0000000004c0716c llvm::VerifierAnalysis::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (ld.lld+0x4c0716c)
#12 0x0000000002a34800 llvm::detail::AnalysisPassModel<llvm::Module, llvm::VerifierAnalysis, llvm::AnalysisManager<llvm::Module>::Invalidator>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) PassBuilder.cpp:0:0
#13 0x0000000004bd3138 llvm::AnalysisManager<llvm::Module>::getResultImpl(llvm::AnalysisKey*, llvm::Module&) (ld.lld+0x4bd3138)
#14 0x0000000004c072a4 llvm::VerifierPass::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (ld.lld+0x4c072a4)
#15 0x0000000004bd0c1c llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (ld.lld+0x4bd0c1c)
#16 0x00000000029bb2d4 llvm::lto::opt(llvm::lto::Config const&, llvm::TargetMachine*, unsigned int, llvm::Module&, bool, llvm::ModuleSummaryIndex*, llvm::ModuleSummaryIndex const*, std::vector<unsigned char, std::allocator<unsigned char>> const&) (ld.lld+0x29bb2d4)
#17 0x00000000029bbb8c llvm::lto::backend(llvm::lto::Config const&, std::function<llvm::Expected<std::unique_ptr<llvm::CachedFileStream, std::default_delete<llvm::CachedFileStream>>> (unsigned int, llvm::Twine const&)>, unsigned int, llvm::Module&, llvm::ModuleSummaryIndex&) (ld.lld+0x29bbb8c)
#18 0x00000000029a3c34 llvm::lto::LTO::runRegularLTO(std::function<llvm::Expected<std::unique_ptr<llvm::CachedFileStream, std::default_delete<llvm::CachedFileStream>>> (unsigned int, llvm::Twine const&)>) (ld.lld+0x29a3c34)
#19 0x00000000029a3084 llvm::lto::LTO::run(std::function<llvm::Expected<std::unique_ptr<llvm::CachedFileStream, std::default_delete<llvm::CachedFileStream>>> (unsigned int, llvm::Twine const&)>, llvm::FileCache) (ld.lld+0x29a3084)
#20 0x0000000002074768 lld::elf::BitcodeCompiler::compile() (ld.lld+0x2074768)
#21 0x0000000001fb78d4 void lld::elf::LinkerDriver::compileBitcodeFiles<llvm::object::ELFType<(llvm::endianness)1, true>>(bool) (ld.lld+0x1fb78d4)
#22 0x0000000001f99c18 void lld::elf::LinkerDriver::link<llvm::object::ELFType<(llvm::endianness)1, true>>(llvm::opt::InputArgList&) (ld.lld+0x1f99c18)
#23 0x0000000001f82c2c lld::elf::LinkerDriver::linkerMain(llvm::ArrayRef<char const*>) (ld.lld+0x1f82c2c)
#24 0x0000000001f7f864 lld::elf::link(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&, bool, bool) (ld.lld+0x1f7f864)
#25 0x0000000001e6d600 lld::unsafeLldMain(llvm::ArrayRef<char const*>, llvm::raw_ostream&, llvm::raw_ostream&, llvm::ArrayRef<lld::DriverDef>, bool) (ld.lld+0x1e6d600)
#26 0x0000000001db8554 lld_main(int, char**, llvm::ToolContext const&) (ld.lld+0x1db8554)
#27 0x0000000001db8b78 main (ld.lld+0x1db8b78)
#28 0x0000ffffb607655c __libc_start_call_main (/lib64/libc.so.6+0x2655c)
#29 0x0000ffffb607663c __libc_start_main@GLIBC_2.17 (/lib64/libc.so.6+0x2663c)
#30 0x0000000001db8130 _start (ld.lld+0x1db8130)
make[4]: *** [scripts/Makefile.vmlinux_o:72: vmlinux.o] Error 139
...
I managed to find two files that trigger this issue so I am going to try and reduce that out.