SIGSEGV compiling AVX-512 inline asm

[athre0z]

This (possibly invalid?) inline asm below segfaults the compiler:

#![feature(asm)]

unsafe fn _mm512_set1_epi64(a: i64) {
    asm! {
        "vpbroadcastq zmm0{k1}, $0"
        :: "m"(a)
        :: "intel"
    }
}

fn main() {
    unsafe { _mm512_set1_epi64(123); }
}

Playground link

Rust version: rustc 1.40.0-nightly (1423bec 2019-11-05)

Backtrace

Thread 4 Crashed:
0   librustc_codegen_llvm-llvm.dylib	0x000000010ce1b74d llvm::X86ATTInstPrinter::getRegisterName(unsigned int) + 13
1   librustc_codegen_llvm-llvm.dylib	0x000000010cbfc97e llvm::X86AsmPrinter::PrintOperand(llvm::MachineInstr const*, unsigned int, llvm::raw_ostream&) + 270
2   librustc_codegen_llvm-llvm.dylib	0x000000010cbfd000 llvm::X86AsmPrinter::PrintIntelMemReference(llvm::MachineInstr const*, unsigned int, llvm::raw_ostream&) + 640
3   librustc_codegen_llvm-llvm.dylib	0x000000010cbfd5fb llvm::X86AsmPrinter::PrintAsmMemoryOperand(llvm::MachineInstr const*, unsigned int, char const*, llvm::raw_ostream&) + 59
4   librustc_codegen_llvm-llvm.dylib	0x000000010da9a65f llvm::AsmPrinter::EmitInlineAsm(llvm::MachineInstr const*) const + 1967
5   librustc_codegen_llvm-llvm.dylib	0x000000010da8ad96 llvm::AsmPrinter::EmitFunctionBody() + 3254
6   librustc_codegen_llvm-llvm.dylib	0x000000010cbfbe78 llvm::X86AsmPrinter::runOnMachineFunction(llvm::MachineFunction&) + 296
7   librustc_codegen_llvm-llvm.dylib	0x000000010dc0ecd9 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) + 281
8   librustc_codegen_llvm-llvm.dylib	0x000000010e4a2a88 llvm::FPPassManager::runOnFunction(llvm::Function&) + 808
9   librustc_codegen_llvm-llvm.dylib	0x000000010e4a2de3 llvm::FPPassManager::runOnModule(llvm::Module&) + 131
10  librustc_codegen_llvm-llvm.dylib	0x000000010e4a3229 llvm::legacy::PassManagerImpl::run(llvm::Module&) + 857
11  librustc_codegen_llvm-llvm.dylib	0x000000010cbdaae2 LLVMRustWriteOutputFile + 562
12  librustc_codegen_llvm-llvm.dylib	0x000000010cb8d4e6 rustc_codegen_llvm::back::write::write_output_file::hf57707ffdc6e18f0 (.llvm.4680699105796709659) + 86
13  librustc_codegen_llvm-llvm.dylib	0x000000010ca95e19 rustc_codegen_llvm::back::write::codegen::_$u7b$$u7b$closure$u7d$$u7d$::h1e2284aa1f07df86 (.llvm.14548906211475689160) + 1225
14  librustc_codegen_llvm-llvm.dylib	0x000000010ca945b3 rustc::util::common::time_ext::h484a300a27ce3e24 + 163
15  librustc_codegen_llvm-llvm.dylib	0x000000010cb9cc55 _$LT$rustc_codegen_llvm..LlvmCodegenBackend$u20$as$u20$rustc_codegen_ssa..traits..write..WriteBackendMethods$GT$::codegen::ha65c2290ec2d1389 + 3317
16  librustc_codegen_llvm-llvm.dylib	0x000000010cabefa2 std::sys_common::backtrace::__rust_begin_short_backtrace::h4b331c6d068dc9d3 + 3746
17  librustc_codegen_llvm-llvm.dylib	0x000000010cac02fb std::panicking::try::do_call::h721f6a3e03c50e53 (.llvm.15542101850647140514) + 43
18  libstd-cd43daae2cf7ddf1.dylib 	0x0000000107be6d1f __rust_maybe_catch_panic + 31
19  librustc_codegen_llvm-llvm.dylib	0x000000010caa5156 core::ops::function::FnOnce::call_once$u7b$$u7b$vtable.shim$u7d$$u7d$::h125a629455a19778 + 134
20  libstd-cd43daae2cf7ddf1.dylib 	0x0000000107bb8a0e _$LT$alloc..boxed..Box$LT$F$GT$$u20$as$u20$core..ops..function..FnOnce$LT$A$GT$$GT$::call_once::h9b41d7adac010663 + 62
21  libstd-cd43daae2cf7ddf1.dylib 	0x0000000107be5a5e std::sys::unix::thread::Thread::new::thread_start::h0725fe9398379348 + 142
22  libsystem_pthread.dylib       	0x00007fff68993d76 _pthread_start + 125
23  libsystem_pthread.dylib       	0x00007fff689905d7 thread_start + 15

[nagisa]

Please try with a LLVM build that has assertions enabled.

[athre0z]

As requested, I just built the latest rustc (475c713) from source, with LLVM assertions enabled.

>>> rustc -V
rustc 1.40.0-dev

Compiling rustc-sigsegv v0.1.0 (/Users/ath/Development/rustc-sigsegv)
unknown operand type!
UNREACHABLE executed at /Users/ath/Development/rust/src/llvm-project/llvm/lib/Target/X86/X86AsmPrinter.cpp:207!
error: could not compile `rustc-sigsegv`.

Caused by:
  process didn't exit successfully: `rustc --edition=2018 --crate-name rustc_sigsegv src/main.rs --error-format=json --json=diagnostic-rendered-ansi --crate-type bin --emit=dep-info,link -C opt-level=3 -C metadata=cfaa57f8238538cc -C extra-filename=-cfaa57f8238538cc --out-dir /Users/ath/Development/rustc-sigsegv/target/release/deps -L dependency=/Users/ath/Development/rustc-sigsegv/target/release/deps -C target-cpu=native` (signal: 6, SIGABRT: process abort signal)

Thread 5 Crashed:
0   libsystem_kernel.dylib        	0x00007fff7275c47a __pthread_kill + 10
1   libsystem_pthread.dylib       	0x00007fff72819707 pthread_kill + 384
2   libsystem_c.dylib             	0x00007fff726e4a08 abort + 120
3   librustc_codegen_llvm-llvm.dylib	0x000000010585f41e llvm::llvm_unreachable_internal(char const*, char const*, unsigned int) + 462
4   librustc_codegen_llvm-llvm.dylib	0x0000000103d8553d llvm::X86AsmPrinter::PrintOperand(llvm::MachineInstr const*, unsigned int, llvm::raw_ostream&) + 493
5   librustc_codegen_llvm-llvm.dylib	0x0000000103d85f50 llvm::X86AsmPrinter::PrintIntelMemReference(llvm::MachineInstr const*, unsigned int, llvm::raw_ostream&) + 752
6   librustc_codegen_llvm-llvm.dylib	0x0000000103d86679 llvm::X86AsmPrinter::PrintAsmMemoryOperand(llvm::MachineInstr const*, unsigned int, char const*, llvm::raw_ostream&) + 57
7   librustc_codegen_llvm-llvm.dylib	0x00000001042bf513 llvm::AsmPrinter::EmitInlineAsm(llvm::MachineInstr const*) const + 1939
8   librustc_codegen_llvm-llvm.dylib	0x00000001042ada06 llvm::AsmPrinter::EmitFunctionBody() + 2854
9   librustc_codegen_llvm-llvm.dylib	0x0000000103d84848 llvm::X86AsmPrinter::runOnMachineFunction(llvm::MachineFunction&) + 296
10  librustc_codegen_llvm-llvm.dylib	0x00000001044c7c6a llvm::MachineFunctionPass::runOnFunction(llvm::Function&) + 330
11  librustc_codegen_llvm-llvm.dylib	0x000000010518ddf0 llvm::FPPassManager::runOnFunction(llvm::Function&) + 1040
12  librustc_codegen_llvm-llvm.dylib	0x000000010518e113 llvm::FPPassManager::runOnModule(llvm::Module&) + 131
13  librustc_codegen_llvm-llvm.dylib	0x000000010518e5a2 llvm::legacy::PassManagerImpl::run(llvm::Module&) + 898
14  librustc_codegen_llvm-llvm.dylib	0x0000000103d5f41f LLVMRustWriteOutputFile + 559
15  librustc_codegen_llvm-llvm.dylib	0x0000000103d25a16 rustc_codegen_llvm::back::write::write_output_file::h759bbedac00052e7 + 86
16  librustc_codegen_llvm-llvm.dylib	0x0000000103d10325 rustc_codegen_llvm::back::write::codegen::_$u7b$$u7b$closure$u7d$$u7d$::h1c521ce99173cfc9 (.llvm.8720060979851273667) + 1141
17  librustc_codegen_llvm-llvm.dylib	0x0000000103d0f9e3 rustc::util::common::time_ext::h9514d078fc909e9a + 163
18  librustc_codegen_llvm-llvm.dylib	0x0000000103d290fc rustc_codegen_llvm::back::write::codegen::h9f2d7d8d3aa37443 + 3196
19  librustc_codegen_llvm-llvm.dylib	0x0000000103d42a23 rustc_codegen_ssa::back::write::execute_work_item::h7528378acd4d9784 + 499
20  librustc_codegen_llvm-llvm.dylib	0x0000000103d5bb92 std::sys_common::backtrace::__rust_begin_short_backtrace::hfced81a9c03b20d6 + 242
21  librustc_codegen_llvm-llvm.dylib	0x0000000103c524cb std::panicking::try::do_call::h1930a25734e038db (.llvm.14567149245432969043) + 43
22  libstd-148845df6e670d53.dylib 	0x000000010389438f __rust_maybe_catch_panic + 31
23  librustc_codegen_llvm-llvm.dylib	0x0000000103d305c6 core::ops::function::FnOnce::call_once$u7b$$u7b$vtable.shim$u7d$$u7d$::he0fb440a524af8d4 + 134
24  libstd-148845df6e670d53.dylib 	0x000000010388ad1e _$LT$alloc..boxed..Box$LT$F$GT$$u20$as$u20$core..ops..function..FnOnce$LT$A$GT$$GT$::call_once::h2b7e113d1172c209 + 62
25  libstd-148845df6e670d53.dylib 	0x00000001038617de std::sys_common::thread::start_thread::h651378ca55643958 + 142
26  libstd-148845df6e670d53.dylib 	0x0000000103882eb9 std::sys::unix::thread::Thread::new::thread_start::hf3afdbafdcb0fb09 + 9
27  libsystem_pthread.dylib       	0x00007fff72819d76 _pthread_start + 125
28  libsystem_pthread.dylib       	0x00007fff728165d7 thread_start + 15

It is worth noting that this only occurs when building with --release -- debug builds are fine.

[nagisa]

Filled as https://bugs.llvm.org/show_bug.cgi?id=43952

[JohnTitor]

I think this issue should be fixed by #67759.

[Amanieu]

This issue does not apply to the new asm! (RFC 2850) which doesn't support memory constraints.

The legacy llvm_asm! is deprecated and is no longer maintained.