<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/54218>54218</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang crashes at -Os and above: Assertion `Parent == Other->Parent && "cross-BB instruction order comparison"' failed 
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          zhendongsu
      </td>
    </tr>
</table>

<pre>
    Related to https://github.com/llvm/llvm-project/issues/54195

```
[509] % clangtk -v
clang version 15.0.0 (https://github.com/llvm/llvm-project.git d5d03135a7160586e2b09dc47c7021379252fbbd)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /local/suz-local/opfuzz/bin
Found candidate GCC installation: /usr/lib/gcc/i686-linux-gnu/8
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/6.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Found candidate GCC installation: /usr/lib/gcc/x86_64-linux-gnu/8
Selected GCC installation: /usr/lib/gcc/x86_64-linux-gnu/7.5.0
Candidate multilib: .;@m64
Candidate multilib: 32;@m32
Candidate multilib: x32;@mx32
Selected multilib: .;@m64
[510] % 
[510] % clangtk -O1 small.c; ./a.out
[511] % 
[511] % clangtk -Os small.c
clang-15: /local/suz-local/software/clangbuild/llvm-project/llvm/lib/IR/Instruction.cpp:113: bool llvm::Instruction::comesBefore(const llvm::Instruction*) const: Assertion `Parent == Other->Parent && "cross-BB instruction order comparison"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace, preprocessed source, and associated run script.
Stack dump:
0.      Program arguments: /local/suz-local/software/local/clang-trunk/bin/clang-15 -cc1 -triple x86_64-unknown-linux-gnu -emit-obj --mrelax-relocations -disable-free -clear-ast-before-backend -main-file-name small.c -mrelocation-model static -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -mllvm -treat-scalable-fixed-error-as-warning -debugger-tuning=gdb -fcoverage-compilation-dir=/local/suz-local/software/emitesting/bugs/20220304-clangtk-m64-O3-mllvm-enable-constraint-elimination-build-174437/delta -resource-dir /local/suz-local/software/local/clang-trunk/lib/clang/15.0.0 -I /usr/local/include/csmith -I /local/suz-local/software/local/include -internal-isystem /local/suz-local/software/local/clang-trunk/lib/clang/15.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Os -fdebug-compilation-dir=/local/suz-local/software/emitesting/bugs/20220304-clangtk-m64-O3-mllvm-enable-constraint-elimination-build-174437/delta -ferror-limit 19 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/small-0fa05a.o -x c small.c
1.      <eof> parser at end of file
2.      Optimizer
 #0 0x0000564eb93f131f PrintStackTraceSignalHandler(void*) Signals.cpp:0:0
 #1 0x0000564eb93eeadd SignalHandler(int) Signals.cpp:0:0
 #2 0x00007fe418e03980 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x12980)
 #3 0x00007fe417ab4e87 raise /build/glibc-uZu3wS/glibc-2.27/signal/../sysdeps/unix/sysv/linux/raise.c:51:0
 #4 0x00007fe417ab67f1 abort /build/glibc-uZu3wS/glibc-2.27/stdlib/abort.c:81:0
 #5 0x00007fe417aa63fa __assert_fail_base /build/glibc-uZu3wS/glibc-2.27/assert/assert.c:89:0
 #6 0x00007fe417aa6472 (/lib/x86_64-linux-gnu/libc.so.6+0x30472)
 #7 0x0000564eb8ac98ac (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x31b88ac)
 #8 0x0000564eb84ab70a llvm::RecurrenceDescriptor::isFirstOrderRecurrence(llvm::PHINode*, llvm::Loop*, llvm::MapVector<llvm::Instruction*, llvm::Instruction*, llvm::DenseMap<llvm::Instruction*, unsigned int, llvm::DenseMapInfo<llvm::Instruction*, void>, llvm::detail::DenseMapPair<llvm::Instruction*, unsigned int> >, std::vector<std::pair<llvm::Instruction*, llvm::Instruction*>, std::allocator<std::pair<llvm::Instruction*, llvm::Instruction*> > > >&, llvm::DominatorTree*) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x2b9a70a)
 #9 0x0000564eb96c5d92 llvm::LoopVectorizationLegality::canVectorizeInstrs() (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3db4d92)
#10 0x0000564eb96c7466 llvm::LoopVectorizationLegality::canVectorize(bool) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3db6466)
#11 0x0000564eb9622813 llvm::LoopVectorizePass::processLoop(llvm::Loop*) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3d11813)
#12 0x0000564eb9625871 llvm::LoopVectorizePass::runImpl(llvm::Function&, llvm::ScalarEvolution&, llvm::LoopInfo&, llvm::TargetTransformInfo&, llvm::DominatorTree&, llvm::BlockFrequencyInfo&, llvm::TargetLibraryInfo*, llvm::DemandedBits&, llvm::AAResults&, llvm::AssumptionCache&, std::function<llvm::LoopAccessInfo const& (llvm::Loop&)>&, llvm::OptimizationRemarkEmitter&, llvm::ProfileSummaryInfo*) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3d14871)
#13 0x0000564eb9625e09 llvm::LoopVectorizePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3d14e09)
#14 0x0000564eba6186f1 llvm::detail::PassModel<llvm::Function, llvm::LoopVectorizePass, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x4d076f1)
#15 0x0000564eb8b571ec llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x32461ec)
#16 0x0000564eb6ff4061 llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function> >, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Function> >::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x16e3061)
#17 0x0000564eb8b56c0a llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3245c0a)
#18 0x0000564eb6ff49c1 llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::PreservedAnalyses, llvm::AnalysisManager<llvm::Module> >::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x16e39c1)
#19 0x0000564eb8b553c4 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module> >::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x32443c4)
#20 0x0000564eb972e030 (anonymous namespace)::EmitAssemblyHelper::RunOptimizationPipeline(clang::BackendAction, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream> >&, std::unique_ptr<llvm::ToolOutputFile, std::default_delete<llvm::ToolOutputFile> >&) (.constprop.836) BackendUtil.cpp:0:0
#21 0x0000564eb9731002 clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, llvm::StringRef, llvm::Module*, clang::BackendAction, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream> >) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x3e20002)
#22 0x0000564eba43d67b clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x4b2c67b)
#23 0x0000564ebb348df9 clang::ParseAST(clang::Sema&, bool, bool) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x5a37df9)
#24 0x0000564eba43c178 clang::CodeGenAction::ExecuteAction() (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x4b2b178)
#25 0x0000564eb9dd3c91 clang::FrontendAction::Execute() (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x44c2c91)
#26 0x0000564eb9d6e23a clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x445d23a)
#27 0x0000564eb9ea1ae3 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x4590ae3)
#28 0x0000564eb6d31d01 cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x1420d01)
#29 0x0000564eb6d2db99 ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&) driver.cpp:0:0
#30 0x0000564eb6c53e79 main (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x1342e79)
#31 0x00007fe417a97c87 __libc_start_main /build/glibc-uZu3wS/glibc-2.27/csu/../csu/libc-start.c:344:0
#32 0x0000564eb6d2d70a _start (/local/suz-local/software/local/clang-trunk/bin/clang-15+0x141c70a)
clang-15: error: unable to execute command: Aborted
clang-15: error: clang frontend command failed due to signal (use -v to see invocation)
clang version 15.0.0 (https://github.com/llvm/llvm-project.git d5d03135a7160586e2b09dc47c7021379252fbbd)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /local/suz-local/opfuzz/bin
clang-15: note: diagnostic msg: 
********************

PLEASE ATTACH THE FOLLOWING FILES TO THE BUG REPORT:
Preprocessed source(s) and associated run script(s) are located at:
clang-15: note: diagnostic msg: /tmp/small-c9f9f4.c
clang-15: note: diagnostic msg: /tmp/small-c9f9f4.sh
clang-15: note: diagnostic msg: 

********************
[512] % 
[512] % cat small.c
short a, c, e, *g;
int *b, d;
char f;
void h() {
  e = c ? a / c : 0;
  *b = d;
}
int main () {
  while (b) {
    while (1) {
      *b && (f = 0);
      h();
      break;
    }
    *g = f--;
  }
  return 0;
}
```

@fhahn 
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJztW1lv4zgS_jXJCyFD9_GQB8eJOwHSmyDJzAD7YlAUZWsiS1pSSjv967eKkmxRcY7uthezO9twfJDFqq8OFosiOy6Tl7N7ntOaJ6QuyaquK3niTE_sObyWWb1q4gkr1_Ajz5_7D6MS5Z-c1fAzk7LhEr54rhV5J-bFiTnt3n2ze7U_vXPPjE68C3Jie4TltFjWT8R4bnvVb_LMhczKgljexJyYQBj-GJ4JEJDES0zHcjwaWL7phT63YzNKmBuwwLQtJ4hsz07jODmxo1b2IxVLXoMQsgn9he8aTfFUlN8KI8-KZmMsi6ajWwlOE7IuE54jdVXKbNN2XReypnnOk4tMYBfiKhnN4VM2343-e1mlzffv8CXOinbgvGyKhDBaJFkCPiBfZjOStcxoDabomDVSIMssRiMwhnb3Q38A0J6Hv8iw033I0j8Cywm49vBsgyOwPA7Szk0PPId4hTl3IIizLbh1k9cZDgRGkxPn_MQ11777HpVjd2Tw5R2yzZZu0xNutXhPKE58y-wn_r62bTK4tYhcgyUmDHgAI3tOJ2VTD8ZYe_hYr_nILZ9ddjEs752pKcu0_kYFh6-KOm6yPHmd7vqkoxxzfY9v4DzRMPTdhFUViLAsBwXFZZkTRQ_py5kO6NoGyGJcnvO0RKEhK6H_DXIb0l9EFAUynkrJBXYQSK53gLmoyYlzAS9yW6-4ME6cy77Z9uEFHzYTpZTG-bkKto4xKUXCBTBeV1RkEiXZJ3ZAUppBKpu0tru7uZw-XBLZxGtIrpTEzZIIXpWi_rX1gkCQARiWNwknAJswQeWKxJQ91YIysMmMVCBIlIyDwgmRZSPaZhxJpSxZppYt0RREMpFVdQf5oQYmJGnW6I22yYSu6E6US0HXBPJ9swbzyM_FQ9_URhEYr3jqUnjfZnnEYMwi0JlVOX9zHSEGByMaZfwnMYy1gGV3Y8A78Ed3SGIkmaRxzo1UcA4sc06FQWVtxCpMDDQOB-WNNc0KIwUvGQVd8z7YieLZcTPUOkUgs9QZ9qSgOTeqMitqDmvURVEWICJd03plcCGKEn6klQFRhuaHQLuAADHSojQEpr8M1ERa4KQCEUOoBHB5RiUH5GlTfMuKxKgRPxj2wgZrqIXVYFWDFjF8F5qagquGJS-4UMAwQNBynNaGBEu3Bsg2PEFcKEMa4IkCEICBOMTfEmIcGEEDyFkmMUhnJdQOdAm8IZizNpWCNVHRjx2MTuGyRn7g12aJ4Wmbtm06pmt0ScWAfGbcOi1cgxcKZWsJ8EVt8DxbZ0UrV-UOwwpc1wmAFbihpgQc3UYwwvrpqGsTj2qDz65OMq4HS0Y3rJtZSCxBvVVH9Emh_bw0VLQUNDcy-SJrvj4o8I8E7dXoXdLPrJf2fDJ5_baH_LVAvsEv7LXgnbXHfN4f_eMi1OJmpGoe_IWDPW2nLtLVxIqgAWzBjK7AB6DuxJ5YauLmQJdkdFmUgIqBcs8cU0v2nQP8stIaZF7BGJokwAaywcViAfXT4mr6--Xi4o_p_dxezObXi-nDV5AA3Es0Xw3LAFgAU6RhptT0oKYgxoYwvUawcIU4cWa8TGH9JLAiwipLaE0w4ZYpwWzbUtpIeVvVoNt3SKWqDQQ5JjE3JvzzfJfHkZNajpWSOwEGUwvSI65qD9kSvHwFK1gOQ-3wucySbn1vu2RXRJjqb8vb0nlz2IgkZMwMJH3IyO4YBSl3rZCbThSaZLGA5AQm5guBNUO4nUp7ZgV0VLXaCU1kidPp3NxYNnDZ7qdQjDMUE9DY5WFAIHgkJyrs2uJqCcyY0fyzcb49bH_aExsDSSot-ukJsyHhFcYq5P1N2_Cs0AAy-FSssWycepausDtC4gepRWhcKk0_h6ROWmuoUUpIOBLi6UKo76QUrEpVpbbAemoR08_r3o7bfmlFRrpIfyzSDexP-I6h13zlNZjwga15LRhGWUhZBH89z1-vkVqhVhwCV01sqIl1aRyYdFAK33PWCChnGb_gbZ1XirYnk_NMyPoWy9gdFQDeDb67uv5HiZl5ipXjrv0GUsurxq-0-l3lGsgDb5fis3fK9GHfBS8kB5YfMGsKDHWOxXC9n8F1kZYfMFF5xLnUxye8hsjTed3R7CPtNECQCju-MA3aEc-9ibYt1cdM3-wbMYeMjAXsIfmTwZ_aEGk2LtVKVopHKLm7THzYiLfjiEJAaxEfaencZ14S2aPg_L1b9NQqe8OXUGnXL93OkRZ9L1faSoX40MCdJHYB1xY4LkPmCHjg-v7PAQesuEM-CmwfUGmw9eXTt-3Qct6Aze8g6XZh1-4921QR7skdh4duWYBMg26PoHthYH0MHWRcr6tcgw1LZzcrRnPgAXdd4vK5zJu9_ShD5aBxR_vkFAqbQsL-dL2XZjTBRr3nYJunueD_aiBzv7wj5CaLBRUdxatEu4YaiCfnGWzpx8OnsH7IJt_XI2WzrlDjGWWrHts26aS9uYaJB00xZRgViKR7JqOesLyKDxWBezJOVzmq6XEPyMXTJRTJuCkfU96JEqvOh2a9Hqp-hKhzIai0qHPGUcfN6FNR97mIm0Jp9yIz-ZUWsGnXc_t2UGe7Y6gL2mjqukN1qW-Ffmq9sZCitl_bI4B9oF9NHN1MI_9yKO-eedKag8ufMpJa1v57zO8mZgDW1czvaQVg7AUWZ0M7ocnfg_o3MJtjuz5YRTObPzSbn6au6R8iao9n7v9Hv-VzB7ykuTEYRb_PtO0PuK3J-WPZQ0P3TBO62wWNFW8H_JDa3ZDjxa7HBhUwKh2OYzdiPxa7vZazT5rqULG3NdXbkfeXcwBGHdhXc0A0ijrPYe4nksA-s_-vmQvi1QVrDM1l6xufwOamoy4o0KIsXtZlIwmexMhKnVxFLUqs6_Cwbh3nL1c8r3g3Ye-bYlgE3mUVz7NCnQKq5-NtZdye9Uy3KXdbmDZFBuXyoqp1mwj6bVF9E1nNFxJPU9baoISnFKrgBUwjXvMPBmp75Y_kPsIu7rapq6aeZ21kfEboaNRAovLmRFXWsAGrJqGjGjt7_FZn-esnm-ghfY8XwF7VtMnAoOiNjkkrWLf3xe4R9GWxVO5Q6g9IrjhNuHjgVLDVbdUe2fU7gBHpDPLVF158QNVubT4guoFv-0gG-7daZMXynqf7smG3W_qLRdbBpyy3wfXaswpb2zlT10n8IN5jhxnYtFn3c7N9mq62tO3Bym9FNoqU6cMjjKn5pj5OgRzbDJBqqmjbsdhxwySNhqrc4WkF4NKBPsDusguW9lFL_3loyB51AkCkQXZH1mdWEO6ZIdPBjYjLDWdNzfvAPMIjLbBtDDg0oNrmI0oSh0XWEOhcoLO382WI9DgYXWYDBA2jr2P0ue1Q3Zh4EMiFuoeGj8D32vNtpY4Sx66XAExND63UjTi1KHe0HN0i3qnz3N1m0NG_UvcYj0VcLzIBnoZfr1oTx0pMiBVmLfBChlbUTIWgL5iSnRlbUdFn7mm3DdLb-gf4x1DDcm0TUGpqRLoadhJHEeltP7MeVZIYKPOAB6Xtgwz1VHGfTiqCEpE9c7F3fdaPR33mOTyICNrt0Ao7rg2shwpvj0-7w7IoYGFAFgs8D4OViYp60QH51PEck3iYps4l26-qU_FRR3WO6-qq22N74wFXK_jg3rbY8LBhePNNHcnjl0Yd6OP1Ld76HK-A4SNU7JziISdP3hne3tVNuwzSj-1ujZGkUZzb41vUrpGcGM-qjXOSDab0EOPf8O7v0LhFiaXTlOwuQpC1XCp2XRT9wmtwKbu7zTd9fJzOrsjj1SWZ397c3P5x_Y8vZH59c_lAHm9V8_lvX8j95d3t_SN6oB277zZeKHHev3kjb0sgOFEHe9BL6y3LT5pAv8TBojRK3X13O3-UhVz9hCcO5Q-8umrvuc66bQNr6VdU5ApvLVC1fuCb2mwBwyXeuFUUmbrzOY2xI9m2qmSdbn_iUkNWfe0SdK2EcLxFShi8zwlFi6nvU2JuRxLFXJHtuJ8EFzvhu3yusf62gtyA7fGoY9BlverqxfWXWMNUiVY3TRyNrtNm1BrDnH3S2rZYO-ZLxTA1jKGKOxrB60YUAwNs-8b_uaF9d810RVcFOU3OnCRyInpaZ3XOz9oMpy64col3ivASl5ozcfmsou0_dKeXnDYiP_uV_-RhW-Hp6swLbCdOoiBiFhRmThR5tsNN34SaD7IvD09zGvNcnkFAQzSfZmf9DTN8am2ZkzROzciCqiMJnNBxPLAc7FVgZ4-CJ6VYnoozhUFdUHPNPJO13HVCqsEbCrznT5sapsbZ9xWsR2WxlM2pQnym4P4b3duvIQ">