RISC-V Assertion failure in SelectionDagBuilder.cpp when compiling CheriBSD-compiler-rt with 128bit intrinsics: `(PartVT.isInteger() || PartVT == MVT::x86mmx) && ValueVT.isInteger() && "Unknown mismatch!"'

[romameie]

Using commit 578ea4f (latest on main at time of writing)
When compiling subrepo-cheri-compiler-rt/lib/builtins/fixdfti.c from https://github.com/CTSRD-CHERI/cheribsd in a custom context for RISC-V purecap target -target riscv64-none-elf -march=rv64imafdcxcheri -mabi=l64pc128d -mxcheri-norvc -mno-relax.

The exact same build step succeeds with the Morello LLVM fork's baremetal release.

clang: /tools_temp/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:534: void getCopyToParts(llvm::SelectionDAG &, const llvm::SDLoc &, llvm::SDValue, llvm::SDValue *, unsigned int, llvm::MVT, const llvm::Value *, OptionalCallingConv::ID, ISD::NodeType): Assertion `(PartVT.isInteger() || PartVT == MVT::x86mmx) && ValueVT.isInteger() && "Unknown mismatch!"' failed.

Processed source: fixdfti-e74d5d.c.txt
Run script: fixdfti-e74d5d.sh.txt

Full trace:

clang: /tools_temp/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:534: void getCopyToParts(llvm::SelectionDAG &, const llvm::SDLoc &, llvm::SDValue, llvm::SDValue *, unsigned int, llvm::MVT, const llvm::Value *, Optional<CallingConv::ID>, ISD::NodeType): Assertion `(PartVT.isInteger() || PartVT == MVT::x86mmx) && ValueVT.isInteger() && "Unknown mismatch!"' failed.
PLEASE submit a bug report to https://github.com/CTSRD-CHERI/llvm-project/issues and include the crash backtrace, preprocessed source, and associated run script.
If you built clang from source, please provide a reduced test case by running:
        $LLVM_BUILD_DIR/bin/creduce_crash_testcase.py <reproducer>.sh
Stack dump:
0.      Program arguments: clang -falign-functions=16 -falign-loops=16 -mstack-alignment=16 -nostdinc -nostdlib -nodefaultlibs -ffreestanding -Wcheri -fno-delete-null-pointer-checks -ftrapv -c -MT riscv64/compiler_rt/common/arch/cheri/freebsd/lib/freebsd/contrib/subrepo-cheri-compiler-rt/lib/builtins/fixdfti.c.o -MD -MP -MF riscv64/compiler_rt/common/arch/cheri/freebsd/lib/freebsd/contrib/subrepo-cheri-compiler-rt/lib/builtins/fixdfti.c.o.d -g -O0 -fPIC -o riscv64/compiler_rt/common/arch/cheri/freebsd/lib/freebsd/contrib/subrepo-cheri-compiler-rt/lib/builtins/fixdfti.c.o /src/lib/freebsd/contrib/subrepo-cheri-compiler-rt/lib/builtins/fixdfti.c -Wno-missing-prototypes -Wno-missing-declarations -Wno-strict-prototypes -Wno-old-style-definition -Wno-redundant-decls -D__FreeBSD__ -D__ELF__ -DRISCV_XLEN=64 -target riscv64-none-elf -march=rv64imafdcxcheri -mabi=l64pc128d -mxcheri-norvc -mno-relax -I /src/include/common -I /src/compat/include/freebsd/include -I /src/compat/include/freebsd/sys -I /src/compat/include/freebsd/sys/sys -I /src/lib/freebsd/libc/include -I /src/include/arch/riscv64 -I /src/compat/freebsd/sys -I /src/compat/include/freebsd/sys/riscv/ -I /src/compat/include/freebsd/sys/riscv/machine/
1.      <eof> parser at end of file
2.      Code generation
3.      Running pass 'Function Pass Manager' on module '/src/lib/freebsd/contrib/subrepo-cheri-compiler-rt/lib/builtins/fixdfti.c'.
4.      Running pass 'RISCV DAG->DAG Pattern Instruction Selection' on function '@__fixint'
 #0 0x00007f4d927d4643 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/usr/local/bin/../lib/libLLVMSupport.so.15git+0x1ee643)
 #1 0x00007f4d927d22be llvm::sys::RunSignalHandlers() (/usr/local/bin/../lib/libLLVMSupport.so.15git+0x1ec2be)
 #2 0x00007f4d926d6303 (anonymous namespace)::CrashRecoveryContextImpl::HandleCrash(int, unsigned long) CrashRecoveryContext.cpp:0:0
 #3 0x00007f4d926d64ee CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #4 0x00007f4d920c5520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #5 0x00007f4d921199fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #6 0x00007f4d920c5476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #7 0x00007f4d920ab7f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #8 0x00007f4d920ab71b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #9 0x00007f4d920bce96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
#10 0x00007f4d91b75869 getCopyToParts(llvm::SelectionDAG&, llvm::SDLoc const&, llvm::SDValue, llvm::SDValue*, unsigned int, llvm::MVT, llvm::Value const*, llvm::Optional<unsigned int>, llvm::ISD::NodeType) SelectionDAGBuilder.cpp:0:0
#11 0x00007f4d91b96174 llvm::TargetLowering::LowerCallTo(llvm::TargetLowering::CallLoweringInfo&) const (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x210174)
#12 0x00007f4d91aeff1e llvm::DAGTypeLegalizer::ExpandIntRes_XMULO(llvm::SDNode*, llvm::SDValue&, llvm::SDValue&) (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x169f1e)
#13 0x00007f4d91ae350e llvm::DAGTypeLegalizer::ExpandIntegerResult(llvm::SDNode*, unsigned int) (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x15d50e)
#14 0x00007f4d91afddb7 llvm::DAGTypeLegalizer::run() (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x177db7)
#15 0x00007f4d91b02df0 llvm::SelectionDAG::LegalizeTypes() (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x17cdf0)
#16 0x00007f4d91c4ad40 llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x2c4d40)
#17 0x00007f4d91c4948e llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x2c348e)
#18 0x00007f4d91c455ce llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/usr/local/bin/../lib/../lib/libLLVMSelectionDAG.so.15git+0x2bf5ce)
#19 0x00007f4d95cc9b09 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (/usr/local/bin/../lib/libLLVMCodeGen.so.15git+0x31ab09)
#20 0x00007f4d934f9435 llvm::FPPassManager::runOnFunction(llvm::Function&) (/usr/local/bin/../lib/libLLVMCore.so.15git+0x25e435)
#21 0x00007f4d935018f1 llvm::FPPassManager::runOnModule(llvm::Module&) (/usr/local/bin/../lib/libLLVMCore.so.15git+0x2668f1)
#22 0x00007f4d934f9e7c llvm::legacy::PassManagerImpl::run(llvm::Module&) (/usr/local/bin/../lib/libLLVMCore.so.15git+0x25ee7c)
#23 0x00007f4d963aa2f6 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>) (/usr/local/bin/../lib/libclangCodeGen.so.15git+0xd62f6)
#24 0x00007f4d967b41e0 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/usr/local/bin/../lib/libclangCodeGen.so.15git+0x4e01e0)
#25 0x00007f4d8fc8ae35 clang::ParseAST(clang::Sema&, bool, bool) (/usr/local/bin/../lib/../lib/libclangParse.so.15git+0x36e35)
#26 0x00007f4d9503c255 clang::FrontendAction::Execute() (/usr/local/bin/../lib/libclangFrontend.so.15git+0x161255)
#27 0x00007f4d94f9e44f clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/usr/local/bin/../lib/libclangFrontend.so.15git+0xc344f)
#28 0x00007f4d96d7c721 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/usr/local/bin/../lib/libclangFrontendTool.so.15git+0x4721)
#29 0x00005597336e30ca cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/usr/local/bin/clang-15+0x130ca)
#30 0x00005597336e099e ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) driver.cpp:0:0
#31 0x00007f4d94c84692 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::$_1>(long) Job.cpp:0:0
#32 0x00007f4d926d6218 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/usr/local/bin/../lib/libLLVMSupport.so.15git+0xf0218)
#33 0x00007f4d94c83fcd clang::driver::CC1Command::Execute(llvm::ArrayRef<llvm::Optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (/usr/local/bin/../lib/libclangDriver.so.15git+0xcafcd)
#34 0x00007f4d94c3f4d8 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/usr/local/bin/../lib/libclangDriver.so.15git+0x864d8)
#35 0x00007f4d94c3f79e clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/usr/local/bin/../lib/libclangDriver.so.15git+0x8679e)
#36 0x00007f4d94c600c5 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/usr/local/bin/../lib/libclangDriver.so.15git+0xa70c5)
#37 0x00005597336dfddd clang_main(int, char**) (/usr/local/bin/clang-15+0xfddd)
#38 0x00007f4d920acd90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#39 0x00007f4d920ace40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#40 0x00005597336dd1d5 _start (/usr/local/bin/clang-15+0xd1d5)
clang-15: error: clang frontend command failed with exit code 134 (use -v to see invocation)
clang version 15.0.0 (https://github.com/CTSRD-CHERI/llvm-project.git 578ea4f7ef67d589f0ca7d10ec9e383333567421)
Target: riscv64-none-unknown-elf
Thread model: posix
InstalledDir: /usr/local/bin
clang-15: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang-15: note: diagnostic msg: /tmp/fixdfti-e74d5d.c
clang-15: note: diagnostic msg: /tmp/fixdfti-e74d5d.sh
clang-15: note: diagnostic msg: 

********************

[romameie]

The same issue occurs with df2e7bd and ed9d996 .

[romameie]

The same assertion fails for "fixtfti.c" and "mulvti3.c".

Presumably, there's an issue with 128bit intrinsics.