llc crashes with "UNREACHABLE executed at Value.cpp:620!"

[Quuxplusone]

Bugzilla Link	PR14455
Status	NEW
Importance	P normal
Reported by	Max Kellermann (max@duempel.org)
Reported on	2012-11-29 04:35:11 -0800
Last modified on	2013-02-07 15:15:15 -0800
Version	trunk
Hardware	PC Linux
CC	llvm-bugs@lists.llvm.org, pawel@32bitmicro.com, rafael@espindo.la, wenhan.gu@gmail.com
Fixed by commit(s)
Attachments	TestRadixTree-opt.bc (214164 bytes, application/octet-stream)
Blocks
Blocked by
See also

I compiled LLVM from trunk r168861. I compile a program with clang to LLVM
bitcode, then llvm-link to build one large bitcode file, opt to optimize the
file, and then llc to generate assembly. llc crashes with the following message:

llc TestRadixTree-opt.bc
While deleting: metadata %
An asserting value handle still pointed to this value!
UNREACHABLE executed at Value.cpp:620!
0  llc             0x0000000000eb11e2
1  llc             0x0000000000eb1673
2  libpthread.so.0 0x00007f24916fc030
3  libc.so.6       0x00007f24909f2475 gsignal + 53
4  libc.so.6       0x00007f24909f56f0 abort + 384
5  llc             0x0000000000ea06a9 llvm::llvm_unreachable_internal(char
const*, char const*, unsigned int) + 457
6  llc             0x0000000000e67be6
llvm::ValueHandleBase::ValueIsDeleted(llvm::Value*) + 806
7  llc             0x0000000000e6762e llvm::Value::~Value() + 46
8  llc             0x0000000000e48eae llvm::MDNode::destroy() + 14
9  llc             0x0000000000e453d9 llvm::LLVMContextImpl::~LLVMContextImpl()
+ 3225
10 llc             0x0000000000e43e4c
11 llc             0x0000000000ea39d9 llvm::llvm_shutdown() + 41
12 llc             0x000000000050f063 main + 6323
13 libc.so.6       0x00007f24909deead __libc_start_main + 253
14 llc             0x000000000050d6e9
Stack dump:
0.      Program arguments: llc TestRadixTree-opt.bc
Aborted

(LLVM bitcode file generated by "opt" is attached)

[Quuxplusone]

It may be interesting that llc can grow extremely large before crashing. Another bitcode file (56 MB) results in a 2.1 GB llc process before it crashes. Maybe this is normal, but maybe this is a memory leak, related to this crash bug?

[Quuxplusone]

Attached TestRadixTree-opt.bc (214164 bytes, application/octet-stream): Test file that makes llc crash

[Quuxplusone]

Problem still exists in r169984.

[Quuxplusone]

Problem still exists in r173101

[Quuxplusone]

Problem still exists in r174657

[Quuxplusone]

Correction: r174657 renders a different error message:

llc: DwarfDebug.cpp:1416: void llvm::DwarfDebug::beginFunction(const
llvm::MachineFunction *): Assertion `TheCU && "Unable to find compile unit!"'
failed.
0  llc             0x0000000000d45505 llvm::sys::PrintStackTrace(_IO_FILE*) + 37
1  llc             0x0000000000d459f3
2  libpthread.so.0 0x00007f6f2b46e030
3  libc.so.6       0x00007f6f2a55c475 gsignal + 53
4  libc.so.6       0x00007f6f2a55f6f0 abort + 384
5  libc.so.6       0x00007f6f2a555621 __assert_fail + 241
6  llc             0x000000000090d753
llvm::DwarfDebug::beginFunction(llvm::MachineFunction const*) + 3651
7  llc             0x00000000008f5aad llvm::AsmPrinter::EmitFunctionHeader() +
797
8  llc             0x0000000000541d24
9  llc             0x000000000099a61d
llvm::MachineFunctionPass::runOnFunction(llvm::Function&) + 125
10 llc             0x0000000000ca699c
llvm::FPPassManager::runOnFunction(llvm::Function&) + 364
11 llc             0x0000000000ca6c0b
llvm::FPPassManager::runOnModule(llvm::Module&) + 43
12 llc             0x0000000000ca6f5e
llvm::MPPassManager::runOnModule(llvm::Module&) + 430
13 llc             0x0000000000ca75fb llvm::PassManagerImpl::run(llvm::Module&)
+ 539
14 llc             0x0000000000ca776a llvm::PassManager::run(llvm::Module&) + 10
15 llc             0x00000000004f17af main + 5407
16 libc.so.6       0x00007f6f2a548ead __libc_start_main + 253
17 llc             0x00000000004f01c9
Stack dump:
0.      Program arguments: llc /tmp/TestRadixTree-opt.bc
1.      Running pass 'Function Pass Manager' on module '/tmp/TestRadixTree-
opt.bc'.
2.      Running pass 'X86 AT&T-Style Assembly Printer' on function
'@_gen_result'
Aborted