<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/129236>129236</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] Crash at -O2: Assertion Assertion `(BestFactor.Width == LegacyVF.Width || PlanForEarlyExitLoop...' failed.
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          cardigan1008
      </td>
    </tr>
</table>

<pre>
    This code crashes at `-O2`:

```c
char a;
struct b {
  short c;
  char d;
 long e;
  int f;
} static g;
int h;
void i(struct b j) {
  char k;
 int l;
  for (; j.d; --j.d) {
    l = g.c == 0 ? 0 : 4294967295U % g.c;
 k = l >= 2 || a >> l ? 0 : l;
    h = k;
  }
}
void m() { i(g); }
```

Compiler Explorer: https://godbolt.org/z/WG85qYnc6

Bisected to https://github.com/llvm/llvm-project/commit/30f3752e54fa7cd595a434a985efbe9a7abe9b65, which was committed by @fhahn 

Crash:

```console
clang: /root/llvm-project/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:7589: llvm::VectorizationFactor llvm::LoopVectorizationPlanner::computeBestVF(): Assertion `(BestFactor.Width == LegacyVF.Width || PlanForEarlyExitLoop || planContainsAdditionalSimplifications(getPlanFor(BestFactor.Width), CostCtx, OrigLoop) || planContainsAdditionalSimplifications(getPlanFor(LegacyVF.Width), CostCtx, OrigLoop)) && " VPlan cost model and legacy cost model disagreed"' failed.
```

Backtrace:

```console
Stack dump:
0.      Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/clang -gdwarf-4 -g -o /app/output.s -mllvm --x86-asm-syntax=intel -fno-verbose-asm -S --gcc-toolchain=/opt/compiler-explorer/gcc-snapshot -fcolor-diagnostics -fno-crash-diagnostics -O2 -Wall -Wextra <source>
1.      <eof> parser at end of file
2.      Optimizer
3.      Running pass "function<eager-inv>(float2int,lower-constant-intrinsics,loop(loop-rotate<header-duplication;no-prepare-for-lto>,loop-deletion),loop-distribute,inject-tli-mappings,loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>,infer-alignment,loop-load-elim,instcombine<max-iterations=1;no-verify-fixpoint>,simplifycfg<bonus-inst-threshold=1;forward-switch-cond;switch-range-to-icmp;switch-to-lookup;no-keep-loops;hoist-common-insts;no-hoist-loads-stores-with-cond-faulting;sink-common-insts;speculate-blocks;simplify-cond-branch;no-speculate-unpredictables>,slp-vectorizer,vector-combine,instcombine<max-iterations=1;no-verify-fixpoint>,loop-unroll<O2>,transform-warning,sroa<preserve-cfg>,infer-alignment,instcombine<max-iterations=1;no-verify-fixpoint>,loop-mssa(licm<allowspeculation>),alignment-from-assumptions,loop-sink,instsimplify,div-rem-pairs,tailcallelim,simplifycfg<bonus-inst-threshold=1;no-forward-switch-cond;switch-range-to-icmp;no-switch-to-lookup;keep-loops;no-hoist-common-insts;hoist-loads-stores-with-cond-faulting;no-sink-common-insts;speculate-blocks;simplify-cond-branch;speculate-unpredictables>)" on module "<source>"
4.      Running pass "loop-vectorize<no-interleave-forced-only;no-vectorize-forced-only;>" on function "i"
 #0 0x0000000003e76828 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3e76828)
 #1 0x0000000003e744e4 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3e744e4)
 #2 0x0000000003dc0e18 CrashRecoverySignalHandler(int) CrashRecoveryContext.cpp:0:0
 #3 0x00007e3b78e42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #4 0x00007e3b78e969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #5 0x00007e3b78e42476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #6 0x00007e3b78e287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #7 0x00007e3b78e2871b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #8 0x00007e3b78e39e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
 #9 0x00000000059b6042 llvm::LoopVectorizationPlanner::computeBestVF() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x59b6042)
#10 0x00000000059cd46c llvm::LoopVectorizePass::processLoop(llvm::Loop*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x59cd46c)
#11 0x00000000059cfb19 llvm::LoopVectorizePass::runImpl(llvm::Function&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x59cfb19)
#12 0x00000000059d0193 llvm::LoopVectorizePass::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x59d0193)
#13 0x0000000005546d4e llvm::detail::PassModel<llvm::Function, llvm::LoopVectorizePass, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x5546d4e)
#14 0x000000000381d3f0 llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x381d3f0)
#15 0x000000000119ab8e llvm::detail::PassModel<llvm::Function, llvm::PassManager<llvm::Function, llvm::AnalysisManager<llvm::Function>>, llvm::AnalysisManager<llvm::Function>>::run(llvm::Function&, llvm::AnalysisManager<llvm::Function>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x119ab8e)
#16 0x000000000381bd0b llvm::ModuleToFunctionPassAdaptor::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x381bd0b)
#17 0x0000000001199e3e llvm::detail::PassModel<llvm::Module, llvm::ModuleToFunctionPassAdaptor, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x1199e3e)
#18 0x000000000381b710 llvm::PassManager<llvm::Module, llvm::AnalysisManager<llvm::Module>>::run(llvm::Module&, llvm::AnalysisManager<llvm::Module>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x381b710)
#19 0x00000000041305e8 (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>>&, clang::BackendConsumer*) BackendUtil.cpp:0:0
#20 0x000000000413485e clang::emitBackendOutput(clang::CompilerInstance&, clang::CodeGenOptions&, llvm::StringRef, llvm::Module*, clang::BackendAction, llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>, std::unique_ptr<llvm::raw_pwrite_stream, std::default_delete<llvm::raw_pwrite_stream>>, clang::BackendConsumer*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x413485e)
#21 0x0000000004835d60 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4835d60)
#22 0x000000000642100c clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x642100c)
#23 0x0000000004836168 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4836168)
#24 0x0000000004afe6e5 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4afe6e5)
#25 0x0000000004a81dce clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4a81dce)
#26 0x0000000004bec53e clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x4bec53e)
#27 0x0000000000d4401f cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xd4401f)
#28 0x0000000000d3b93a ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#29 0x000000000487e099 void llvm::function_ref<void ()>::callback_fn<clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const::'lambda'()>(long) Job.cpp:0:0
#30 0x0000000003dc12c4 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x3dc12c4)
#31 0x000000000487e68f clang::driver::CC1Command::Execute(llvm::ArrayRef<std::optional<llvm::StringRef>>, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char>>*, bool*) const (.part.0) Job.cpp:0:0
#32 0x00000000048412ad clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x48412ad)
#33 0x000000000484232e clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x484232e)
#34 0x000000000484a2c5 clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0x484a2c5)
#35 0x0000000000d40e13 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xd40e13)
#36 0x0000000000c11aa4 main (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xc11aa4)
#37 0x00007e3b78e29d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#38 0x00007e3b78e29e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#39 0x0000000000d3b3e5 _start (/opt/compiler-explorer/clang-assertions-trunk/bin/clang+0xd3b3e5)
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzkWl9z5Kay_zT4hdKUhP4_-GEs75yTVFK7tXaSuk8uhNAMMQIdQP6TT38LkEaj8dhrZyepe3NSzo4koPvXv26aBglrzbaC0kuQXoH0-gIPZifVJcGqYVssojAsLmrZPF_e7piGRDYUEoX1jmqIDQRZGHxGIAtBvAah-8tC_0dAuCY7rCAG8RUI19qogRhYQ5DbWwj1TioDiW-F0PVtxjsuxRbSqYkJA1t_A_JrqA02jMCtf2Ibd_7yQbIGMoCKva7fASr3Cp2G-1GoHcYnBa1UEKACxFfw95XFAIPAXhwMhpBDEF_D7YrYX3sZQhBv3L9rmKAyKbMclekvEKDUdhuF37thdvAne4EgyCuQVxD7J59c0yRmjwjCnRs3wYUgv_bmT3Z2FrAH6GzeAlRa5GPHyQ3eK5Xsesapgp-eei4VVVbZzpheW8ehDUCbrWxqyc1Kqi1Amz8A2vz2ryL9z_8IknkZV0xTYmgDjTweysxuqFdEdgBtOH-YfoJeyd8pMQBtiOw6Zi_isI3zFNE0aXFOmrRMcRInuCxS2ta0xDmuaVlnKUAVfNwxsoOP2MadHW6V188QJGG7wzsBR9tsOJ6IPym05NRGIcdiaw0GaKOkNC_RTZhZDdDmVmGhW6k6DdDmV0qMVOwPCtDmJyn7_f2K9D2I13lalM5xVkK8BvF66oENk2KD7c1B66EM1-MLx0I4f4B4TWTXD4ZeUW1-3Xj_WuFrramyne18A6iw7V7y6jfWmN0UkD_RLSbPv26mpz7QrIaNVJ-w4s-fnpixEKa2nmNRSWEwE3rdNMwqwfyGdT1nLSMOobbBRc0o5oR6ixJVsJLaVObJXn5WbGvV-Pj885qWBr2px6lCGUAZBAjBX60QSKQ2sJMN5RCLBnIn7vBpwzTeKkobgBBAOWwx47RZvZxAV5jcG4UJfSvQbgwm97AZut73ClcgLL8ouVW4g1hth44Ko8dIlP04L9zEDOg0MdHGxWuAJ6frwKhB3AO0qZmYmmGwbR6xaoMEBlsYSCsR972VO5h-MCsNg86GHQyCpyILsO4C_SwMfgLxNROGchi0QgYPVNVSU9sOgxsYBFtCAiMlJzvMhI2rt5DazlrgXu-kgUFLJJcqaBjeCqkNI9rrcOvF8vFnBIPfMOcw-I0-GWVzYaXloCy_n0C4jixzIK6obG2K7LHSVNkFh4oGyha2zBGObLfPvWEd-4MqEK5j--DrIAQTW9hjrW0wtIMglkgrD2-pCph4sGpQ0XKJDWLCAFRx-UhVYJ1psDABE0YxoRnRrs3GWGF_AiUNNhTE1Y7ihqqgGXo-xi-Ir4QMekV7rGjQShVwI50mJyFoKKeunwtk_4hpo1g9GApQxYTNR4HhLOhw3zOxnZQHD_s8FFdCWnRUcYofnBpCm0AK_uz177seNXkgTLRUBZizrbDROMnnEjcB5axzXbQhsquZsNo6_BQwQ9U4Q-PraFKjWPsctOypl5ZBJ137-fxM2i2Iq1qKQQdWXGB2iuqd5M0ooJXqEasm0I_MkJ2l3S67453CYksDIwNG7FSaHhsZcCnvh94DuKfU4pZ2IbraSaZNYJcJKZxG7Tv559Y6HWgjFdXBIzNeYdDigRtm14YrzcT98XDdUzJwbGhQc0nu3aPRPj--VliQnVc0dx5Er2jDiME1p3rkhR-4UAFU-Ztgovm7SHcOHISSnIO4-oz8UzMtY8EjVnY-WBhKYhBXvaKaqgcaODedjorvxdNpje2UYaQDcYU5l48TRW6mfPKTYK8yaJXsbNIbun5cC7wg65kRz8Q-QFXDHgJFu6DHTNmuBjNOMOdjCL87DoUMPhSK1tMvo3ERivuoOwqn94aiVfFd0fhmKJZ2dZTCrn8DpzY9LlIvQiBcJ6ey6FnTkIMw5WUrnXnNEKA4hOFTOP0X0zwrUHFQQeln7S--KCaMW3Jv3cKMirmTwo93UhtFceeKggq6JF-6Kv97116ArsKnEZgl1MOOjmAnCU1Owa44xWLoP4sbthWYA1QMwm3BGrfrOTdIC2MGiRYgGxLSqICugP5KiXyg6tmj-jcWDbe6ipG3RR9bx9EnM5bAofvfy49H-TmN67ygCUpROJrji-unIrvLkoAzMTwFWzH4BrLScpU5yG7IDDhZCiyzsiWwt7MYN3f3jPOPSXfjZ-npMdwkz-BWOwo-CjvJs1lwthSMiryNIa7thvdDYt3AWWz-QmxUf1hgVM8Ci6XAuKRl9jGBbsgssDwMsLSsszBB37P9Od9cGMF4qHa-hkuopEky8gpU-gXrcfr2ShKq9U9jRbjoDtD6zJAdqBlydAS5raPy25DVIH7oer6Au5lqYpsdzwvZgpohoyXkJozK-F2QX4dbHYxfC8yfNdM_Y2FLexBXJwbZFefcZjpDZjPjhZlpkjUJPYDZUFugjOsW1vpnu_s8DXZh3kt6_pT19u__Ba2euJnWZLFeFVETt-EBTEflWxD_0WyNfMxspYdsRVGJ6-IcQfiXsfyP9s7I_-yd7CiW6yasD2D-7AryWzlBsqyvG9wbqU4b7Ad8yNxxyF8Sitac2dj8KBRLGn8sFCfrqndS9Cc4eC2S_i8RO1I3E1scR1EevScjnqLzn8PSyMPM0qIMTaI4TGlh1WEhxXMnBw0F7qju3b6x9Og-dcystaZdzZ__TXk_VaVfBzEeMfqKlfWUuzObYnqxAGJ3PkxFs94nRG0a3zII9p-B3vVmyYXdofaPihl6N-1TDwY11B0I3LkTQ_qNgWMyzd6j9lZK_tmdEG-Yj4f36DwadajwJQeVFHrorANdNTw-_cUwfrRhtPvR8MhRSZHSQ5m0Y2aU4AEsaZ_ea_3gTm0JfQmqkg39F3UedIdKR-F6YxQT26-0PZVpnAWnTFyfWPd-EEYNmj3Qr7SthPlyRPxDO5a2lsGbZ21oNy6Bf3-kvMNrZ5uao0_3UxMt9jBJEadNFr6Fxz305xHuzZw_QPxFsKNQWN_cjucS584uI8jZhMWeJktQFIbk0IQvWGm6vrldAryhHR7jr5aSz79nhDqCmaHGR2xnUVacmB5jQPs8-ETJYOgU4-fdhY8QZoCLCj_BLc1oeghwo6xT91PuEOHZsXntM7Z0ia2IGkLhW9nnJH-vG3PuOPUIZ_yLijOpKUnjBf4R6WzGgxxfZH0jyZ45RXhkM-5F8Rg2SRJGLSQkuuswWxYha6Xws83eceW-7nCv7yy-Mc0tnqEKPkjWnBu-xzejL5bo47qMMZyorqJbN-cPbLjpMOd-k--OaU6ZcrRqWRljspv6uVBqFHug6sQyu6yHipyGZenIOBA6HcffKcena52-QRhrQII5rzG5v2uFhTmHiFc8hksVVbLrsGiOZ-tJv-1XMtn7bwIWa9i8Pu_Xrv2Auzvy9BRF_qbGmhG7zrmXKI7CRWf74M4ozIyemo_EYc5t-Nvt1r7ddlnPmdoFjifcDQEo57irGwxQPlOFiukg_0dZv3TG0QuOhkSIHL4pOHXUvq9Eb3BL-fOCy7f9dtYy22Pdh3ocHYdVVrTwvzksLNerHiuzCl_3P1qylkQIN6-y5vyFX6x9E5WLRH000HY4SA_VGzoOu64XRcqBYeeqAJzBcxAdlSgJihH9KB0_ylq_zsWPsv6JabPg4q38u_d9j5l1u_9A5N30HW6P_joSLU0zickRiRiR9DXA1wfXixLgxNr_Gvl_I4lnrT4dMTNt6VGlEdIo9hCnWmOC7RLHepz2316Jz1hdWEwz4kVNF5IowjiBFuv5VHqhs8rjt45lU37wpa4bMgssjgXSJIR3d3bMnTZYmbsDg96tgiYHKsrjIiymKfTCz-gbJ3ZUOn0OeNFcxk0Zl_iCXkZ5EuZJhtL8YneZNk0U17Rs0iiqC5rnSZs2Ca7ztoijqKUX7BKFKA0RKiIU56hY5XGWhlnetjSMwzgiIAlphxlf2fhbSbW9YFoP9DJCJYqzC45ryrX7kBuhESUC6fWFunTfu9bDVoMk5EwbPYswzHD39bcfkV77d_0QGxh8RsvPT8__IepqtTr47vJiUPzyw98WOxI0QJuRh4dL9L8BAAD__0amrOo">