[aarch64] Unknown FP condition! #86917

DigOrDog · 2024-03-28T07:13:44Z

Description

The following code crashes aarch64 backend with "Unknown FP condition!"

Minimal Reproduction

Code

; ModuleID = 'crash-4f3ab3a32f91d152361bae65ffeca42d2fa3e7b9'
source_filename = "M"

define float @f(i1 %0, i16 %1) {
BB:
  %RP = alloca float, align 4
  br label %BB2

BB2:                                              ; preds = %BB2, %BB
  %C2 = fcmp true float 4.200000e+01, 4.200000e+01
  %B2 = and i1 %C2, %0
  %2 = load float, ptr %RP, align 4
  br i1 %B2, label %BB2, label %BB1
BB1:                                              ; preds = %BB2
  ret float %2
}

Stack Trace

Unknown FP condition!
UNREACHABLE executed at /root/llvm-project/llvm/lib/Target/AArch64/GISel/AArch64GlobalISelUtils.cpp:105!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/llc -o /app/output.s -x86-asm-syntax=intel -mtriple=aarch64 -O=0 <source>
1.	Running pass 'Function Pass Manager' on module '<source>'.
2.	Running pass 'InstructionSelect' on function '@f'
 #0 0x0000000003928f08 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x3928f08)
 #1 0x000000000392665c SignalHandler(int) Signals.cpp:0:0
 #2 0x00007f2211a42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #3 0x00007f2211a969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #4 0x00007f2211a42476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #5 0x00007f2211a287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #6 0x000000000387521a (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x387521a)
 #7 0x0000000000cc2500 llvm::AArch64GISelUtils::changeVectorFCMPPredToAArch64CC(llvm::CmpInst::Predicate, llvm::AArch64CC::CondCode&, llvm::AArch64CC::CondCode&, bool&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0xcc2500)
 #8 0x0000000000a8af3c (anonymous namespace)::AArch64InstructionSelector::selectCompareBranch(llvm::MachineInstr&, llvm::MachineFunction&, llvm::MachineRegisterInfo&) (.isra.0) AArch64InstructionSelector.cpp:0:0
 #9 0x0000000000a9085d (anonymous namespace)::AArch64InstructionSelector::select(llvm::MachineInstr&) AArch64InstructionSelector.cpp:0:0
#10 0x00000000040d02a9 llvm::InstructionSelect::runOnMachineFunction(llvm::MachineFunction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x40d02a9)
#11 0x0000000002942d31 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
#12 0x0000000002f01813 llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x2f01813)
#13 0x0000000002f01a51 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x2f01a51)
#14 0x0000000002f022b5 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x2f022b5)
#15 0x000000000082323c compileModule(char**, llvm::LLVMContext&) llc.cpp:0:0
#16 0x00000000007223e6 main (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x7223e6)
#17 0x00007f2211a29d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#18 0x00007f2211a29e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#19 0x0000000000819d5e _start (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x819d5e)
Program terminated with signal: SIGSEGV
Compiler returned: 139

The text was updated successfully, but these errors were encountered:

llvmbot · 2024-03-28T07:29:31Z

@llvm/issue-subscribers-backend-aarch64

Author: None (DigOrDog)

# Description The following code crashes aarch64 backend with "Unknown FP condition!"

Minimal Reproduction

https://godbolt.org/z/7EeccGP3r

Code

; ModuleID = 'crash-4f3ab3a32f91d152361bae65ffeca42d2fa3e7b9'
source_filename = "M"

define float @<!-- -->f(i1 %0, i16 %1) {
BB:
  %RP = alloca float, align 4
  br label %BB2

BB2:                                              ; preds = %BB2, %BB
  %C2 = fcmp true float 4.200000e+01, 4.200000e+01
  %B2 = and i1 %C2, %0
  %2 = load float, ptr %RP, align 4
  br i1 %B2, label %BB2, label %BB1
BB1:                                              ; preds = %BB2
  ret float %2
}

Stack Trace

Unknown FP condition!
UNREACHABLE executed at /root/llvm-project/llvm/lib/Target/AArch64/GISel/AArch64GlobalISelUtils.cpp:105!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.	Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/llc -o /app/output.s -x86-asm-syntax=intel -mtriple=aarch64 -O=0 &lt;source&gt;
1.	Running pass 'Function Pass Manager' on module '&lt;source&gt;'.
2.	Running pass 'InstructionSelect' on function '@<!-- -->f'
 #<!-- -->0 0x0000000003928f08 llvm::sys::PrintStackTrace(llvm::raw_ostream&amp;, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x3928f08)
 #<!-- -->1 0x000000000392665c SignalHandler(int) Signals.cpp:0:0
 #<!-- -->2 0x00007f2211a42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #<!-- -->3 0x00007f2211a969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #<!-- -->4 0x00007f2211a42476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #<!-- -->5 0x00007f2211a287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #<!-- -->6 0x000000000387521a (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x387521a)
 #<!-- -->7 0x0000000000cc2500 llvm::AArch64GISelUtils::changeVectorFCMPPredToAArch64CC(llvm::CmpInst::Predicate, llvm::AArch64CC::CondCode&amp;, llvm::AArch64CC::CondCode&amp;, bool&amp;) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0xcc2500)
 #<!-- -->8 0x0000000000a8af3c (anonymous namespace)::AArch64InstructionSelector::selectCompareBranch(llvm::MachineInstr&amp;, llvm::MachineFunction&amp;, llvm::MachineRegisterInfo&amp;) (.isra.0) AArch64InstructionSelector.cpp:0:0
 #<!-- -->9 0x0000000000a9085d (anonymous namespace)::AArch64InstructionSelector::select(llvm::MachineInstr&amp;) AArch64InstructionSelector.cpp:0:0
#<!-- -->10 0x00000000040d02a9 llvm::InstructionSelect::runOnMachineFunction(llvm::MachineFunction&amp;) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x40d02a9)
#<!-- -->11 0x0000000002942d31 llvm::MachineFunctionPass::runOnFunction(llvm::Function&amp;) (.part.0) MachineFunctionPass.cpp:0:0
#<!-- -->12 0x0000000002f01813 llvm::FPPassManager::runOnFunction(llvm::Function&amp;) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x2f01813)
#<!-- -->13 0x0000000002f01a51 llvm::FPPassManager::runOnModule(llvm::Module&amp;) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x2f01a51)
#<!-- -->14 0x0000000002f022b5 llvm::legacy::PassManagerImpl::run(llvm::Module&amp;) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x2f022b5)
#<!-- -->15 0x000000000082323c compileModule(char**, llvm::LLVMContext&amp;) llc.cpp:0:0
#<!-- -->16 0x00000000007223e6 main (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x7223e6)
#<!-- -->17 0x00007f2211a29d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#<!-- -->18 0x00007f2211a29e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#<!-- -->19 0x0000000000819d5e _start (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x819d5e)
Program terminated with signal: SIGSEGV
Compiler returned: 139

tschuett · 2024-03-28T07:46:47Z

The switch in:

llvm-project/llvm/lib/Target/AArch64/GISel/AArch64GlobalISelUtils.cpp

Line 99 in 38f5596

void AArch64GISelUtils::changeFCMPPredToAArch64CC(

is missing support for FCMP_FALSE and FCMP_TRUE.

marcauberer · 2024-03-28T14:38:01Z

I can confirm that this fixes the issue. Preparing a patch ...

…tion (#86972) Fixes #86917 `FCMP_TRUE` and `FCMP_FALSE` were previously not considered and we ended up in an llvm_unreachable assertion.

…tion (llvm#86972) Fixes llvm#86917 `FCMP_TRUE` and `FCMP_FALSE` were previously not considered and we ended up in an llvm_unreachable assertion. (cherry picked from commit c482fad)

…tion (llvm#86972) Fixes llvm#86917 `FCMP_TRUE` and `FCMP_FALSE` were previously not considered and we ended up in an llvm_unreachable assertion.

…tion (#86972) (#91580) Fixes #86917 `FCMP_TRUE` and `FCMP_FALSE` were previously not considered and we ended up in an llvm_unreachable assertion.

github-actions bot added the new issue label Mar 28, 2024

dtcxzyw added backend:AArch64 llvm:globalisel crash-on-valid and removed new issue labels Mar 28, 2024

marcauberer self-assigned this Mar 28, 2024

marcauberer mentioned this issue Mar 28, 2024

[AArch64][GISEL] Consider fcmp true and fcmp false in cond code selection #86972

Merged

marcauberer closed this as completed in #86972 Mar 28, 2024

marcauberer added a commit that referenced this issue Mar 28, 2024

[AArch64][GISEL] Consider fcmp true and fcmp false in cond code selec…

c482fad

…tion (#86972) Fixes #86917 `FCMP_TRUE` and `FCMP_FALSE` were previously not considered and we ended up in an llvm_unreachable assertion.

DigOrDog mentioned this issue May 5, 2024

LLVM 18.1.5 Release Assets missing some code! #91121

Closed

tstellar pushed a commit that referenced this issue May 9, 2024

[AArch64][GISEL] Consider fcmp true and fcmp false in cond code selec…

0a045c9

…tion (#86972) (#91580) Fixes #86917 `FCMP_TRUE` and `FCMP_FALSE` were previously not considered and we ended up in an llvm_unreachable assertion.

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[aarch64] Unknown FP condition! #86917

[aarch64] Unknown FP condition! #86917

DigOrDog commented Mar 28, 2024

llvmbot commented Mar 28, 2024

Minimal Reproduction

Code

Stack Trace

tschuett commented Mar 28, 2024

marcauberer commented Mar 28, 2024

[aarch64] Unknown FP condition! #86917

[aarch64] Unknown FP condition! #86917

Comments

DigOrDog commented Mar 28, 2024

Description

Minimal Reproduction

Code

Stack Trace

llvmbot commented Mar 28, 2024

Minimal Reproduction

Code

Stack Trace

tschuett commented Mar 28, 2024

marcauberer commented Mar 28, 2024