<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/166525>166525</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [PowerPC][GISel] llc crashed with assertion "legality mutation invalid for match" at all optimization flags
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            backend:PowerPC,
            crash-on-valid
      </td>
    </tr>

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

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

<pre>
    Reproducer: https://godbolt.org/z/bqqMjE93q
Testcase:
```llvm
target datalayout = "e-m:e-Fn32-i64:64-i128:128-n32:64-S128-v256:256:256-v512:512:512"
target triple = "powerpc64le-unknown-linux-musl"

define i64 @backsmith_pure_5(<4 x i16> %conv) {
entry:
  %xor = xor <4 x i16> %conv, zeroinitializer
  %0 = bitcast <4 x i16> %xor to i64
  ret i64 %0
}
```

llc output:
```
llc: /root/llvm-project/llvm/lib/CodeGen/GlobalISel/LegalizerInfo.cpp:206: llvm::LegalizeActionStep llvm::LegalizeRuleSet::apply(const llvm::LegalityQuery&) const: Assertion `mutationIsSane(Rule, Query, Mutation) && "legality mutation invalid for match"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0.      Program arguments: /opt/compiler-explorer/clang-assertions-trunk/bin/llc -o /app/output.s -x86-asm-syntax=intel -O0 -global-isel <source>
1.      Running pass 'Function Pass Manager' on module '<source>'.
2.      Running pass 'Legalizer' on function '@backsmith_pure_5'
 #0 0x000000000419d348 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x419d348)
 #1 0x000000000419a1f4 SignalHandler(int, siginfo_t*, void*) Signals.cpp:0:0
 #2 0x000077968fc42520 (/lib/x86_64-linux-gnu/libc.so.6+0x42520)
 #3 0x000077968fc969fc pthread_kill (/lib/x86_64-linux-gnu/libc.so.6+0x969fc)
 #4 0x000077968fc42476 gsignal (/lib/x86_64-linux-gnu/libc.so.6+0x42476)
 #5 0x000077968fc287f3 abort (/lib/x86_64-linux-gnu/libc.so.6+0x287f3)
 #6 0x000077968fc2871b (/lib/x86_64-linux-gnu/libc.so.6+0x2871b)
 #7 0x000077968fc39e96 (/lib/x86_64-linux-gnu/libc.so.6+0x39e96)
 #8 0x0000000004863325 llvm::LegalizeRuleSet::apply(llvm::LegalityQuery const&) const (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x4863325)
 #9 0x0000000004864b06 llvm::LegalizerInfo::getAction(llvm::LegalityQuery const&) const (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x4864b06)
#10 0x0000000004864f7c llvm::LegalizerInfo::getAction(llvm::MachineInstr const&, llvm::MachineRegisterInfo const&) const (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x4864f7c)
#11 0x00000000048623a5 llvm::LegalizerHelper::legalizeInstrStep(llvm::MachineInstr&, llvm::LostDebugLocObserver&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x48623a5)
#12 0x000000000480d7db llvm::Legalizer::legalizeMachineFunction(llvm::MachineFunction&, llvm::LegalizerInfo const&, llvm::ArrayRef<llvm::GISelChangeObserver*>, llvm::LostDebugLocObserver&, llvm::MachineIRBuilder&, llvm::GISelValueTracking*) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x480d7db)
#13 0x000000000480fbae llvm::Legalizer::runOnMachineFunction(llvm::MachineFunction&) (.part.0) Legalizer.cpp:0:0
#14 0x000000000307fcc9 llvm::MachineFunctionPass::runOnFunction(llvm::Function&) (.part.0) MachineFunctionPass.cpp:0:0
#15 0x00000000036cfa86 llvm::FPPassManager::runOnFunction(llvm::Function&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x36cfa86)
#16 0x00000000036cfe31 llvm::FPPassManager::runOnModule(llvm::Module&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x36cfe31)
#17 0x00000000036d069f llvm::legacy::PassManagerImpl::run(llvm::Module&) (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x36d069f)
#18 0x00000000008fa803 compileModule(char**, llvm::LLVMContext&) llc.cpp:0:0
#19 0x00000000007c7986 main (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x7c7986)
#20 0x000077968fc29d90 (/lib/x86_64-linux-gnu/libc.so.6+0x29d90)
#21 0x000077968fc29e40 __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x29e40)
#22 0x00000000008efc45 _start (/opt/compiler-explorer/clang-assertions-trunk/bin/llc+0x8efc45)
Program terminated with signal: SIGSEGV
Compiler returned: 139
```
</pre>
<img width="1" height="1" alt="" src="http://email.email.llvm.org/o/eJzEWF1z4yoS_TX4hZILoS_rwQ8aJ56bqklNNr41tW8uhJDMDQINoMSeX78FkiPb8Wwld7O7UxPbAvr0Od3NhyDG8EYytgTJF5DczEhvd0ov_7naHWalqg7LR9ZpVfWUaRAVcGdtZ0BUALwGeN2oqlTCzpVuAF7_Anhd_vx5_9dtHv0EqPiTGUuJYW44KkCKhv9CPLcAFZbohllYEUsEOajeQhDdQIAxC1oQFSxYywgHPI1BVKRxwEO8AFER4kUgIzy0bdzTM05SEBWvn8FzErr-6RPjyZ3VvBPs6KpTL0x3NI0FC3r5JNWLDASX_T5oeyMGQ4CKitVcMsjTGIIYlYQ-mZbb3bbrNdsmwBFbxXAPeZiC6BYCnFAlnwHOIci-AFQwafVhiAJ0vXulPYPh-6rpCv5iWnHJLSeC_2L6aIu8ZcldZO1bawdplaPqDTSzA22cIKcluznNxKBOCApVb7veXiRq6HNZB3itlbIAr13ygk6rvxg9ProvXgK8XqmKfWUS4PVXoUoi7jZMALz-xppBwp2s1Zx2ncsTctmC3jwqQFQcBxXUciU3lnVXOh97wTbMDo2k68QB4AVV0tg3g-3hHz3TB4BTlwY_xjksjGHaeYAgRW1vift9ZzZEMoAXDt-FfjRdwftxhE-lg0pd1YjRAzwCQC6fieAVrJWGLbF050oHZ7AmXLBqDlDx8O222NxC05ctt5DAsm-gZp3S1qXrYlZxu-vLOVXtSYTP486N6ZkBeA2JrCCXVPQVg3bHINXE7KCrUasJZWO_sbr3kTXOnT5OaW9R9o1juLGEPsGqb7uhDNAcoPxBq0aTFhLd9C2T1ozVoDrHgqq244LpgO07oTTTrk0Q2QTkGGcTWN3LJ7cycOl1UBgoB0G6zgH5wpsbGOwXaUBMG5iDtGQPohsuLRMw-I5g0Ph6CrhhwpW8Ub2mDES3ABWho_nYS8llAztiDAQ4W_fSq4UPruGeSNI4chlUEraq6t0KgLMzJJy5IOBraK8FPCLUR3SHcW09yNzcAzhCEO3R8V8c5lUUL04q1RzM8ONBc2l9_P90OQN4MQ3S5GWrjNWMtL4CV5BLO9Tj4j9MBMBf0H6kBXA-kg4vSJOwjuGGN5KIP4ishANfeA4raHjDZa22FuDCPT8rXvmf-WhhxvmO_N_gAI8OsixPFzWNcYLRqGZYR_aLdJvG40LcyH7ooHOj5unA2ZlMjKNzwDzNawo7u9OMVNsnLsTH0L39hB5f0o2zFDbGy_so7ThLJ-DkHBgvsjqCpHRLwodgveEEm76BDcsPA4blBJidA0Y5y9OPAXqTCXBxVmGLNIpw8t7V_jfr_LjCn6z2nzY_Bn4T-_yCfVyi9Ap7v9sNTQ2zw7b2f-LvGA783fRGl_zrjP4d_veE7rhkd25vOaG_gm-GPLKGGzsg_neF1hmdhIYXQnFErpWZ_oOJzh9uQVSIsdGrcqeQ30p-I_abMvaGlX3zTdHvpWH6melR5-cpdBomhfhcIaqyqrym8FzbqOK4R15TOPVdijytjt9kvdCaHB5ZDaLV1PjVHQZXOyIbNgWn8Bvvu4J4pazuHr_0XFRXBnhnP4jomdtPn7hsxk3p0xLhQz0lIrpIRF0S9vtE6F5-lx_Ngic_74i2c7f1wVfMix3W0YlP6UQoqynN38bvCO_OSCfErjL6t1Su4F0hlZyRSmlNFqfr5vrB2R2Pah-m8xlpHUlNaU0vKbMofAfle3_CPM_o2PTZdFkUTnSzc7oVSvP6hK6b__Qwnjgn4ndtJ17J_w9Ie1oT6bPDAFrUZIEiODp4DSTdEb9cDKfMk4n17cf9SknL9sctRQh6pfbO9myU0SxfpLAlXH6WrAHyVRVGF4ewvMo_eMb1JhNgeAnIYgS3W2ezNZZouz2R824XLD5xgc8zwWoaJ3AA_6wwDaCDy-OrpWW65ZJYVsEXbndwOFm798zN3dfN7dcfABWr0SXUzPZassp1h1F-elsxq5ZRlUc5mbFlmKU4itI4D2e7ZVhhxFBYR2WW0TxPsySJKkpTikucZGE040uMcBKGKEF5EifhPErysqpylCxSymgeghixlnAxd5U3V7qZ-ffvZZimCU5mgpRMGH-BhrF7G2TSEXxQL0w_rPxVgPv0b-aBkoG_K3DNyc1ML_2bfdk3BsRIcGPN5MVyK_zF3BEquQHJF7-7geTG1frwun8MHZluN957SwGJhUQIqDrLW_5rGFgL0phZr8Xy719MjLF5XuJ_BQAA__9XDj4M">