<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/94810>94810</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            x86 backend crashes when using `-m32 -mapxf`
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

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

<pre>
    The following code:

```cpp
long long xlrandom (long long x, long *random)
{
    return x << *random;
}
```

currently makes trunk x86 Clang crash when using `-m32 -mapxf`, with the following error message:

```
fatal error: error in backend: Cannot select: 0xc73fd30: i32 = X86ISD::CMOV 0xc73f160, Constant:i32<0>, TargetConstant:i8<5>, 0xc73fc50, example.cpp:3:14
 0xc73f160: i32 = shl 0xc73f1d0, 0xc73f630, example.cpp:3:14
    0xc73f1d0: i32,ch = load<(dereferenceable load (s32) from %ir.3, align 8)> 0xc6a31e8, FrameIndex:i32<-1>, undef:i32, example.cpp:3:12
      0xc73f390: i32 = FrameIndex<-1>
      0xc73f940: i32 = undef
    0xc73f630: i8 = and 0xc73f860, Constant:i8<31>, example.cpp:3:14
      0xc73f860: i8,ch = load<(load (s8) from %ir.6, align 4)> 0xc6a31e8, 0xc73f400, undef:i32, example.cpp:3:17
        0xc73f400: i32,ch = load<(dereferenceable load (s32) from %ir.4)> 0xc6a31e8, FrameIndex:i32<-2>, undef:i32, example.cpp:3:18
          0xc73f470: i32 = FrameIndex<-2>
 0xc73f940: i32 = undef
        0xc73f940: i32 = undef
      0xc73f010: i8 = Constant<31>
  0xc73f7f0: i32 = Constant<0>
  0xc73f9b0: i8 = TargetConstant<5>
  0xc73fc50: i32 = X86ISD::CMP 0xc73f2b0, Constant:i8<0>, example.cpp:3:14
    0xc73f2b0: i8 = and 0xc73f860, Constant:i8<32>, example.cpp:3:14
      0xc73f860: i8,ch = load<(load (s8) from %ir.6, align 4)> 0xc6a31e8, 0xc73f400, undef:i32, example.cpp:3:17
 0xc73f400: i32,ch = load<(dereferenceable load (s32) from %ir.4)> 0xc6a31e8, FrameIndex:i32<-2>, undef:i32, example.cpp:3:18
 0xc73f470: i32 = FrameIndex<-2>
          0xc73f940: i32 = undef
 0xc73f940: i32 = undef
      0xc73f240: i8 = Constant<32>
 0xc73fa20: i8 = Constant<0>
In function: _Z8xlrandomxPl
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: /opt/compiler-explorer/clang-trunk/bin/clang++ -gdwarf-4 -g -o /app/output.s -mllvm --x86-asm-syntax=intel -S --gcc-toolchain=/opt/compiler-explorer/gcc-snapshot -fcolor-diagnostics -fno-crash-diagnostics -m32 -mapxf <source>
1.      <eof> parser at end of file
2.      Code generation
3.      Running pass 'Function Pass Manager' on module '<source>'.
4.      Running pass 'X86 DAG->DAG Instruction Selection' on function '@_Z8xlrandomxPl'
 #0 0x000000000376ac58 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x376ac58)
 #1 0x0000000003768da4 llvm::sys::CleanupOnSignal(unsigned long) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3768da4)
 #2 0x00000000036b44f3 llvm::CrashRecoveryContext::HandleExit(int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x36b44f3)
 #3 0x00000000037604be llvm::sys::Process::Exit(int, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x37604be)
 #4 0x0000000000c72bc6 (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc72bc6)
 #5 0x00000000036be0b3 llvm::report_fatal_error(llvm::Twine const&, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x36be0b3)
 #6 0x00000000048da484 llvm::SelectionDAGISel::CannotYetSelect(llvm::SDNode*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48da484)
 #7 0x00000000048e18c5 llvm::SelectionDAGISel::SelectCodeCommon(llvm::SDNode*, unsigned char const*, unsigned int) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48e18c5)
 #8 0x00000000022d776d (anonymous namespace)::X86DAGToDAGISel::Select(llvm::SDNode*) X86ISelDAGToDAG.cpp:0:0
 #9 0x00000000048d79a4 llvm::SelectionDAGISel::DoInstructionSelection() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48d79a4)
#10 0x00000000048e6d81 llvm::SelectionDAGISel::CodeGenAndEmitDAG() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48e6d81)
#11 0x00000000048e99b4 llvm::SelectionDAGISel::SelectAllBasicBlocks(llvm::Function const&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48e99b4)
#12 0x00000000048eb824 llvm::SelectionDAGISel::runOnMachineFunction(llvm::MachineFunction&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48eb824)
#13 0x00000000048db2a1 llvm::SelectionDAGISelLegacy::runOnMachineFunction(llvm::MachineFunction&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x48db2a1)
#14 0x0000000002bde90b llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
#15 0x000000000310cfa2 llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x310cfa2)
#16 0x000000000310d121 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x310d121)
#17 0x000000000310edd0 llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x310edd0)
#18 0x00000000039efe2e clang::EmitBackendOutput(clang::DiagnosticsEngine&, clang::HeaderSearchOptions const&, clang::CodeGenOptions const&, clang::TargetOptions const&, clang::LangOptions const&, 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-trunk/bin/clang+++0x39efe2e)
#19 0x0000000003ff9b15 clang::BackendConsumer::HandleTranslationUnit(clang::ASTContext&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3ff9b15)
#20 0x0000000005f02e3c clang::ParseAST(clang::Sema&, bool, bool) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x5f02e3c)
#21 0x0000000003ffa395 clang::CodeGenAction::ExecuteAction() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x3ffa395)
#22 0x0000000004296ca1 clang::FrontendAction::Execute() (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4296ca1)
#23 0x000000000421c6ab clang::CompilerInstance::ExecuteAction(clang::FrontendAction&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x421c6ab)
#24 0x000000000437c8b3 clang::ExecuteCompilerInvocation(clang::CompilerInstance*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x437c8b3)
#25 0x0000000000c7494c cc1_main(llvm::ArrayRef<char const*>, char const*, void*) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc7494c)
#26 0x0000000000c6ea4d ExecuteCC1Tool(llvm::SmallVectorImpl<char const*>&, llvm::ToolContext const&) driver.cpp:0:0
#27 0x0000000004042db9 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
#28 0x00000000036b43f3 llvm::CrashRecoveryContext::RunSafely(llvm::function_ref<void ()>) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x36b43f3)
#29 0x0000000004042fd9 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
#30 0x0000000004009577 clang::driver::Compilation::ExecuteCommand(clang::driver::Command const&, clang::driver::Command const*&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4009577)
#31 0x0000000004009f2d clang::driver::Compilation::ExecuteJobs(clang::driver::JobList const&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&, bool) const (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4009f2d)
#32 0x0000000004013f7c clang::driver::Driver::ExecuteCompilation(clang::driver::Compilation&, llvm::SmallVectorImpl<std::pair<int, clang::driver::Command const*>>&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0x4013f7c)
#33 0x0000000000c71df1 clang_main(int, char**, llvm::ToolContext const&) (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc71df1)
#34 0x0000000000b4e0e4 main (/opt/compiler-explorer/clang-trunk/bin/clang+++0xb4e0e4)
#35 0x0000727e9f429d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#36 0x0000727e9f429e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#37 0x0000000000c6e4ee _start (/opt/compiler-explorer/clang-trunk/bin/clang+++0xc6e4ee)
clang++: error: clang frontend command failed with exit code 70 (use -v to see invocation)
Compiler returned: 70
``` 

Godbolt link that reproduces this issue: https://godbolt.org/z/Yhdfe4aYP
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzkWl9z46iy_zTKC-WUhGT9eciDYyfZbM3cSU1yt3bviwtJLZs7CHwBJc799KcAKRaK82fOek-drTM1k7GhaX7d_Gi6CUQpuuEAF8H8Mpivzkint0Je3JBSUmDfySMFeVaK-vniYQuoEYyJJ8o3qBI1BPEiCFdBOPxMQ_e32u1cCxN8g-yPPZOE16JFAc5HrQFeuk8BXjiBABe9tuzSfUAIIQm6kxztURAvg3g5Eo8vB_HVBMUYWtVJCVyzZ9SSH6CQlh3_gfZ5ipaMGGskUVv0tAWOOmXMC9Jw1sYYzVqy2zdGG16iJ6q3SHtuACmFRC0oRTZv-sN9bYgmzA0I4kU_knJUkuoH8Nq0LQnnQiMFDCptGsJ9lcVNHYfmC40xCuIV-j1Pb-9XZrJ4sfz67bdeKnIgl4IrTbgZTmMcxMswiK9MxwORG9Dj7jyIl_O-1-mo5lYH7Em7Y3BuFjJexEG8iJJ-MQ5zjRCpLRs66vCgLY0_0obQaJxTGOBltbVamSC1WW-c1yChAQm8AlIysD2GScqIF6iRllhzKs9jMyFhdMNRbqgUX5kJUhJHkJuua0lauOU17F_8M4t6F3S8hqZvPg4bH2APwOPC88RYf6_51ZAi8Ya4aSf-SPslz60I4XXfnr9eZLOK8WDD-75GIy1W-zFnvzg3n_g2Pfg2OeZbpzsJw885MxvjQqPRp-DBUYDHFh9_evFzH-8L4uwdAuADAT6z9p_lyCAVRmOWHEjR86GXd7JZ42kcCYevZItyrHcaOFzM8AaYuPFmhLrrhXB5lLvhp6h7UPEz2wL_fbfF32Y__Nw2QJ_m-c9sBJy8tRFe7UCC3xA9bINbjpqOV5oKbkTX_5MP6cv-jjmRuy9Xi_srpLqypRoRVHYbJGEnpEZaoK3WO2Xoj68DfL2hetuV55VJbq4Zexz-m-2k-F9z0ONrqlQHKsDXltOUV6yrwaYaLjMxOYKWpAKzFjsJOykqUApqpEQnXbMZSZQSFSUaaiQ7jlQl6U6fO8j3mlQ_UN21u5c8JTwPwuJOio0kLSJy07XAtQGOAnwtdgZZJdodZSBnsN8xIUGaNpMzzWwOFeDrkvKhLcCXAb5Es039RGQzS9Bsg2bCKCO7nVHZ6V2nzxWatcYBaDbb5-mMqHamnrkm-yBeUa6Bodk9ms02VTXTQrBqSygP4tW7mIyw4mSntkKjWVMJJuSspmTDhdK0UmjWcDGz3vSbD1meSS57dw5MiIyDgngJojG7Z0ekAomIRsBrJBrUUAZOEhvJpagBbYCDJJY8tic2Pd87zk2-uCNKoQBn1z2_0J1p-Eo42RgzMiQ4akXdMTBSHiCc9QuZHFP4e56i1eJmFsRXq8UNuuVKy85NcW_TSYPH6R-4bWdIwgm98RCAAhyHKNyHw584S0k1z5FlsA3t6lm5D3eScm359eBImh-EJHlaC6UlkDbANlZSrk10CnD-Z1gW4Mtw32N6KRoM6GgCOq9Jcgz0kgHh3e4bv6cbTliA847bWqi2JckJIRoEHkTsQUzLJGniEcSlYel3qMQjyOel4Br22vX8QnjN4GpPdYDzU_rRYfBAxhM_hkkJxxffxiL3ZQxtiUoh2An9aBB4EJMxxLDKcFmlJ5nMqfLmmk_WDMJyvGYu-K9tkbd2Rd54Fzw8UQ6oMqdNvwtO6hsHx8ObjvEmhoL5eBu8BIXV4ub2HljPPFuA_gHadXsm3K_-y9T8eHEq1D0oD3Xmo4Yor-YfonatJvguRduaOHcctslq-h1ebYkclsPvOeGu6vF7BuZjAzGusyy1KRvhgj-3olOIkxbUzobRwpnwe56uFjcP4ojRb6-QzcGBDQP7zC20_17QFBOSZAX5mCQrMTpdRodLfkJiGCCHqyAcR-GEGGmdRx_TWdRwA3zB66uW6tXi5qQgLQYPZDQBWRTlx-50rQvGLomi1SUT1Q_lLetLrnAIHyczwSD0TMATE8ocf2yC7Pg3_pVUW8phQOuZ8KrvlDYYiJ4N8YTVJSbvceULbEj1_G9giQXqWeIdcLisoQhL9CYYk0uOzDiK_zXw8x2R-jw0347oex03DC7_MIzCqiF4hOv6zgwdstqfRvTnz0OHyHNlOoFcRzj6BOSvNhn3KdA3nRKuQePBzSZwoa7DEVw24uwI-G27O2zJvxy0weSB9g63uIAGMCA30GWHLdWX7rr7my0FA5yPuleHuuyKbyiHPlUaifwCpAZ5D0RW2287QxvlZVUj0T74fyDlLrc-EPpC-OaYyCimaEn55js0fvPg9cVEYe-ERU_88ZBbrmWn6CN8h2bJ9Z2WQbw8dD82_Ra_pgzun5WGtr-xUbp2PR2n_9fBejcZaQqx3ZOkGtZDOTYaVENDOqbXNTDQ8MHA-Kqf87VJS8FV1xoWnSxP7InkMc1LXOKmKcpo_h6aUfX0IAlXzBbo_83phIKL-4eh4DrhVnH4xgZgL5-ZNyGGuBobcEekgsX9gw_vHlri1Q-nrSN6HB7QaOJpEhfzI9tsMVyX2SIQqk7D4tR5YT-7B8_PV3CRViQaw7uWZjlfttoY3ymTQTexh8zPQnBUpaT0HefmurU3kBUc993bppww83DgPPRe5pHEWZWXsRfKHc6DEY-iIq8xvzLyhOWjA-Whnk8uBJIiqVBVReuWUP88XEhJnk28jpd-LdgHtml9-ChofULwDpqHPfWxp0CSGg1uXkYPdp-Pq72WMPYbVFr0x_4RQyanlNHRhzevmKglfQR5NNXDfkUeJrguC-uNkd7hRnEtrUNtr9td9qgwIhVhrCTVj3XDDdIDQ9zcPVuWkangCa-nG_Xowr0cXsKezYR5x9bhSH45rl4GrNfVfh9F7ktp6i5ztFGDyXrREzYNay0J1WronqgjjBn2CznqNyKLQ4C2zHE-t0MCnDHSljUJcHZwlXscYUR_FeXx9cind4fxJ-8Ov3f8njTAnj13vr90J7xejBt_qxZTXjV1gf6TeTGpxd4igH8pn4RhMc-yNx1nF4y8OvoGb3qxejLQCLyVEL8jupjcb77Y9ucDvrN1zCL_st8INLj-WWf8Kkr1tid-FeUXqvRbef-rIPyy-DtCzbr3V-GfdV7PkL_QhQ2uPRf6GVQYxU1WvQV3NfrsZQBHjv63XP8vdOGJEg3nE89p8STRiOqmTzuHVGMAbaPGot_zHx_Fp0kuDBwPr_-bkjKBEBJkkJ5kQqfPm3DIxDKcQdEkuKiLsJ-L0TLA1_s8XafJjFHe7Wcb3rmO6lyJ89QqtUM8nelUJyQhWq_NsLXSROr1yKJPzwKJP0s2zcMSAOT0n2Z1rMaXKcfdw7NA88G2o6bP-VHVs7whlEHtniLCnmr7EBNl1redAjR7RFogBYDoKCXv5xqy8f49JdhHh1k4ea6Ixo8Yb0RdCqYRo_wH0luikX19UHcVKKS3VCH7dsEomrx6cAPPhdwE-Pr_A3z9x7ZuICF_3J3VF3FdxAU5g4soi7KsyIs0OdteVEDKOonyJMqyrCrwvDYBaV4UZUTyMIIzeoFDnIRpmGGMcZKcp1UTF3kUFlWTlvOmDJIQWkLZudlpZu4zC--iSPIoPGOkBKbsU1eMOTz12DEO5qszeWEfZZTdRgVJyKjS6qBFU83gYp-nw3NN9zAD1LuPRs86yS7--ccgDvTjBf5HAAAA__9Pi_Mf">