llvm/include/llvm/Support/Casting.h:109: Assertion failed

[dcb314]

Clang can be made to say:

clang: /home/dcb38/llvm/trunk/llvm/include/llvm/Support/Casting.h:109: static bool llvm::isa_impl_cl<To, const From*>::doit(const From*) [with To = llvm::UndefValue; From = llvm::Constant]: Assertion `Val && "isa<> used on a null pointer"' failed.

codegen_timing_486-53904b.sh.gz
codegen_timing_486-53904b.c.gz

[llvmbot]

@llvm/issue-subscribers-c

Author: None (dcb314)

Clang can be made to say:

clang: /home/dcb38/llvm/trunk/llvm/include/llvm/Support/Casting.h:109: static bool llvm::isa_impl_cl<To, const From*>::doit(const From*) [with To = llvm::UndefValue; From = llvm::Constant]: Assertion `Val && "isa<> used on a null pointer"' failed.

codegen_timing_486-53904b.sh.gz
codegen_timing_486-53904b.c.gz

[Endilll]

Can't reproduce on trunk and 18.1.0 with assertions: https://godbolt.org/z/8Wxvqcz4o
Can you provide full compiler output, not just the assertion? We need stack trace to identify where and at which stage the crash occurred.

[dcb314]

The version of the compiler I used was from this morning.
Git hash 1cf75cc.

Stack backtrace is

 #7 0x00007f701984887f abort (/lib64/libc.so.6+0x2687f)
 #8 0x00007f701984879b _nl_load_domain.cold (/lib64/libc.so.6+0x2679b)
 #9 0x00007f7019858187 (/lib64/libc.so.6+0x36187)
#10 0x0000000001b7cfe4 llvm::InstCombinerImpl::foldCmpLoadFromIndexedGlobal(llvm::LoadInst*, llvm::GetElementPtrInst*, llvm::GlobalVariable*, llvm::CmpInst&, llvm::ConstantInt*) /home/dcb38/llvm/trunk/llvm/include/llvm/Support/Casting.h:109:5
#11 0x0000000001ba58c2 llvm::InstCombinerImpl::visitICmpInst(llvm::ICmpInst&) /home/dcb38/llvm/trunk/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp:7300:3
#12 0x0000000001b0538b llvm::InstCombinerImpl::run() /home/dcb38/llvm/trunk/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp:5089:36
#13 0x0000000001b06ae8 combineInstructionsOverFunction(llvm::Function&, llvm::InstructionWorklist&, llvm::AAResults*, llvm::AssumptionCache&, llvm::TargetLibraryInfo&, llvm::TargetTransformInfo&, llvm::DominatorTree&, llvm::OptimizationRemarkEmitter&, llvm::BlockFrequencyInfo*, llvm::BranchProbabilityInfo*, llvm::ProfileSummaryInfo*, llvm::LoopInfo*, llvm::InstCombineOptions const&) /home/dcb38/llvm/trunk/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp:5389:5
#14 0x0000000001b07d13 llvm::InstCombinePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) /home/dcb38/llvm/trunk/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp:5448:3
#15 0x000000000221ab9d llvm::detail::PassModel<llvm::Function, llvm::InstCombinePass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) /home/dcb38/llvm/trunk/llvm/include/llvm/IR/PassManagerInternal.h:91:3
#16 0x0000000001a5885e llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) /home/dcb38/llvm/trunk/llvm/include/llvm/IR/PassManager.h:228:20
#17 0x0000000000b45efd llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) /home/dcb38/llvm/trunk/llvm/include/llvm/IR/PassManagerInternal.h:91:3

Machine type is x86_64. AMD Zen 3 I think.

When the reduction is finished, I will post it here.

[Endilll]

Thank you for reducing it yourself! Please make sure you follow this guidance, in order for your reduction to be as useful as possible: #89807 (comment)

[dcb314]

It works fine with yesterday's clang:

llvm $ ~/llvm/results.20240521/bin/clang -c -w -O1 codegen_timing_486-53904b.c
llvm $ 

But not todays ;-|

llvm $ ~/llvm/results.20240522/bin/clang -c -w -O1 codegen_timing_486-53904b.c
lang: /home/dcb38/llvm/trunk/llvm/include/llvm/Support/Casting.h:109: static bo
ol llvm::isa_impl_cl<To, const From*>::doit(const From*) [with To = llvm::UndefV
alue; From = llvm::Constant]: Assertion `Val && "isa<> used on a null pointer"' 
failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and i
nclude the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.	Program arguments: /home/dcb38/llvm/results.20240522/bin/clang -c -w -O1
 codegen_timing_486-53904b.c
1.	<eof> parser at end of file
2.	Optimizer
 #0 0x0000000001fa377e llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) /home
/dcb38/llvm/trunk/llvm/lib/Support/Unix/Signals.inc:723:22
 #1 0x0000000001fa08eb llvm::sys::RunSignalHandlers() /home/dcb38/llvm/trunk/llv
m/lib/Support/Signals.cpp:105:20
 #2 0x0000000001eed398 HandleCrash /home/dcb38/llvm/trunk/llvm/lib/Support/Crash
RecoveryContext.cpp:73:5
 #3 0x0000000001eed398 CrashRecoverySignalHandler(int) /home/dcb38/llvm/trunk/ll
vm/lib/Support/CrashRecoveryContext.cpp:390:62
 #4 0x00007fbec565fbb0 __restore_rt (/lib64/libc.so.6+0x3dbb0)
 #5 0x00007fbec56b0884 __pthread_kill_implementation (/lib64/libc.so.6+0x8e884)
 #6 0x00007fbec565fafe gsignal (/lib64/libc.so.6+0x3dafe)
 #7 0x00007fbec564887f abort (/lib64/libc.so.6+0x2687f)
 #8 0x00007fbec564879b _nl_load_domain.cold (/lib64/libc.so.6+0x2679b)
 #9 0x00007fbec5658187 (/lib64/libc.so.6+0x36187)
#10 0x0000000001b7cfe4 llvm::InstCombinerImpl::foldCmpLoadFromIndexedGlobal(llvm
::LoadInst*, llvm::GetElementPtrInst*, llvm::GlobalVariable*, llvm::CmpInst&, ll

Yesterday's compiler has git hash 6246b49
and today's has 1cf75cc.

That looks like 142 commits, so that should be easy (for someone who knows
what they are doing), to bisect.

[dtcxzyw]

Reproducer: https://godbolt.org/z/c1oT7cncd

target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"

@opcode_timings = constant [2 x ptr] [ptr @timing_mr, ptr @timing_mr]
@timing_mr = external global i32

define i1 @codegen_timing_486_prefix(i64 %idxprom) {
entry:
  %arrayidx = getelementptr [2 x ptr], ptr @opcode_timings, i64 0, i64 %idxprom
  %0 = load ptr, ptr %arrayidx, align 8
  %cmp.i = icmp ult ptr %0, inttoptr (i64 10001 to ptr)
  ret i1 %cmp.i
}

opt: /home/dtcxzyw/WorkSpace/Projects/compilers/llvm-project/llvm/include/llvm/Support/Casting.h:109: static bool llvm::isa_impl_cl<To, const From*>::doit(const From*) [with To = llvm::UndefValue; From = llvm::Constant]: Assertion `Val && "isa<> used on a null pointer"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.      Program arguments: bin/opt -passes=instcombine reduced.ll -S
 #0 0x0000732e2ac08db0 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/libLLVMSupport.so.19.0git+0x208db0)
 #1 0x0000732e2ac05dbf llvm::sys::RunSignalHandlers() (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/libLLVMSupport.so.19.0git+0x205dbf)
 #2 0x0000732e2ac05f15 SignalHandler(int) Signals.cpp:0:0
 #3 0x0000732e2a642520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x0000732e2a6969fc __pthread_kill_implementation ./nptl/pthread_kill.c:44:76
 #5 0x0000732e2a6969fc __pthread_kill_internal ./nptl/pthread_kill.c:78:10
 #6 0x0000732e2a6969fc pthread_kill ./nptl/pthread_kill.c:89:10
 #7 0x0000732e2a642476 gsignal ./signal/../sysdeps/posix/raise.c:27:6
 #8 0x0000732e2a6287f3 abort ./stdlib/abort.c:81:7
 #9 0x0000732e2a62871b _nl_load_domain ./intl/loadmsgcat.c:1177:9
#10 0x0000732e2a639e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
#11 0x0000732e264f7f99 llvm::InstCombinerImpl::foldCmpLoadFromIndexedGlobal(llvm::LoadInst*, llvm::GetElementPtrInst*, llvm::GlobalVariable*, llvm::CmpInst&, llvm::ConstantInt*) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMInstCombine.so.19.0git+0xd7f99)
#12 0x0000732e2652b2a3 llvm::InstCombinerImpl::visitICmpInst(llvm::ICmpInst&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMInstCombine.so.19.0git+0x10b2a3)
#13 0x0000732e2647f6e4 llvm::InstCombinerImpl::run() (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMInstCombine.so.19.0git+0x5f6e4)
#14 0x0000732e264806a4 combineInstructionsOverFunction(llvm::Function&, llvm::InstructionWorklist&, llvm::AAResults*, llvm::AssumptionCache&, llvm::TargetLibraryInfo&, llvm::TargetTransformInfo&, llvm::DominatorTree&, llvm::OptimizationRemarkEmitter&, llvm::BlockFrequencyInfo*, llvm::BranchProbabilityInfo*, llvm::ProfileSummaryInfo*, llvm::LoopInfo*, llvm::InstCombineOptions const&) InstructionCombining.cpp:0:0
#15 0x0000732e264815cc llvm::InstCombinePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMInstCombine.so.19.0git+0x615cc)
#16 0x0000732e27ec3516 llvm::detail::PassModel<llvm::Function, llvm::InstCombinePass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMPasses.so.19.0git+0xc3516)
#17 0x0000732e24d51300 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMCore.so.19.0git+0x351300)
#18 0x0000732e29ed3cf6 llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMX86CodeGen.so.19.0git+0xd3cf6)
#19 0x0000732e24d4ff97 llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMCore.so.19.0git+0x34ff97)
#20 0x0000732e29ed5426 llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMX86CodeGen.so.19.0git+0xd5426)
#21 0x0000732e24d4e1b1 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/../lib/libLLVMCore.so.19.0git+0x34e1b1)
#22 0x0000732e2b0996c4 llvm::runPassPipeline(llvm::StringRef, llvm::Module&, llvm::TargetMachine*, llvm::TargetLibraryInfoImpl*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::ToolOutputFile*, llvm::StringRef, llvm::ArrayRef<llvm::PassPlugin>, llvm::ArrayRef<std::function<void (llvm::PassBuilder&)>>, llvm::opt_tool::OutputKind, llvm::opt_tool::VerifierKind, bool, bool, bool, bool, bool, bool, bool) (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/libLLVMOptDriver.so.19.0git+0x2d6c4)
#23 0x0000732e2b0a6b3a optMain (/home/dtcxzyw/WorkSpace/Projects/compilers/LLVM/llvm-build/bin/../lib/libLLVMOptDriver.so.19.0git+0x3ab3a)
#24 0x0000732e2a629d90 __libc_start_call_main ./csu/../sysdeps/nptl/libc_start_call_main.h:58:16
#25 0x0000732e2a629e40 call_init ./csu/../csu/libc-start.c:128:20
#26 0x0000732e2a629e40 __libc_start_main ./csu/../csu/libc-start.c:379:5
#27 0x0000610f2523b095 _start (bin/opt+0x1095)
Aborted (core dumped)

LLVM version: cf12830