Hi everyone.
When I try to compile OpenCL kernel on my notebook with Radeon HD 7340 GPU, I have segfault inside clBuildProgram function. If I comment line
b += (val << r) | (val >> (32 - r));
in my kernel source, it executes normally.
Valgrind detected problems in the LLVM functions:
==26271== Invalid read of size 8
==26271== at 0xA4D0C96: llvm::R600TargetLowering::FoldOperand(llvm::SDNode*, unsigned int, llvm::SDValue&, llvm::SDValue&, llvm::SDValue&, llvm::SDValue&, llvm::SDValue&, llvm::SelectionDAG&) const (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0xA4D13E2: llvm::R600TargetLowering::PostISelFolding(llvm::MachineSDNode*, llvm::SelectionDAG&) const (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0xA4523FE: ??? (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x988B2C3: llvm::SelectionDAGISel::DoInstructionSelection() (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x988A974: llvm::SelectionDAGISel::CodeGenAndEmitDAG() (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x988962D: llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x9886965: llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x9589DF8: llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x941A667: llvm::FPPassManager::runOnFunction(llvm::Function&) (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x941A8C2: llvm::FPPassManager::runOnModule(llvm::Module&) (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x941AC8A: llvm::legacy::PassManagerImpl::run(llvm::Module&) (in /usr/lib/x86_64-linux-gnu/libLLVM-7.so.1)
==26271== by 0x7637540: ??? (in /usr/lib/x86_64-linux-gnu/libMesaOpenCL.so.1.0.0)
==26271== Address 0x50 is not stack'd, malloc'd or (recently) free'd
All this looks like a bug in the compiler.
Environment: Linux notebook 4.19.0-6-amd64 #1 SMP Debian 4.19.67-2+deb10u1 (2019-09-20) x86_64 GNU/Linux
Sources and full valgrind log are attached.
Build: gcc -o host host.c -lOpenCL -ggdb
