<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/55606>55606</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [AArch64] crash on compiling umaxv/vcvtfxu2fp neon intrinsics, assertion "unexpected vector type"
        </td>
    </tr>

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

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

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

<pre>
    
The following IR when compiled via llc for the aarch64 backend will crash or hit in assertion if they're enabled.

[Godbolt link](https://godbolt.org/z/Ts75WMdTs)

```
; Compiled with llc --mtriple=aarch64-none-none -O0
; Function Attrs: mustprogress nofree nosync nounwind readnone willreturn uwtable
define dso_local float @do_stuff(<8 x i16> noundef %var_135) local_unnamed_addr #0 {
entry:
  %vmaxv.i = call i32 @llvm.aarch64.neon.umaxv.i32.v8i16(<8 x i16> %var_135) #2
  %vcvts_n_f32_u32 = call float @llvm.aarch64.neon.vcvtfxu2fp.f32.i32(i32 %vmaxv.i, i32 1)
  ret float %vcvts_n_f32_u32
}

; Function Attrs: mustprogress nocallback nofree nosync nounwind readnone willreturn
declare float @llvm.aarch64.neon.vcvtfxu2fp.f32.i32(i32, i32) #1

; Function Attrs: mustprogress nocallback nofree nosync nounwind readnone willreturn
declare i32 @llvm.aarch64.neon.umaxv.i32.v8i16(<8 x i16>) #1
```

The assertion we get is in `tryCombineFixedPointConvert`:
```
unexpected vector type!
UNREACHABLE executed at /root/llvm-project/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp:15076!
```

[Full LLC crash log](https://github.com/llvm/llvm-project/files/8735112/2022_05_19_llc_crash_log.txt)

The DAG at the point of the assertion:

```
SelectionDAG has 12 nodes:
  t0: ch = EntryToken
          t2: v8i16,ch = CopyFromReg t0, Register:v8i16 %0
        t14: v8i16 = AArch64ISD::UMAXV t2
      t15: i32 = extract_vector_elt t14, Constant:i64<0>
    t9: f32 = llvm.aarch64.neon.vcvtfxu2fp TargetConstant:i64<627>, t15, Constant:i32<2>
  t11: ch,glue = CopyToReg t0, Register:f32 $s0, t9
  t12: ch = AArch64ISD::RET_FLAG t11, Register:f32 $s0, t11:1
```

The following is a minimal repro of the error via C++ when compiled with -O1:

[Godbolt link](https://godbolt.org/z/nPMr81qo9)

```
#include <arm_neon.h>
float32_t do_stuff(uint16x8_t Input) {
        uint16_t MaxElem = vmaxvq_u16(Input);
        float32_t MaxAsFloat = vcvts_n_f32_u32(MaxElem, 1);
        return MaxAsFloat;
}
```

I have verified that this repros on the latest trunk (6e00a34cdb49ba1d4b72ec274e52260da9c52380).

For context: this code was generated by a fuzzer, it was not manually written.




</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJy9Vktz2zYQ_jXUBWMOCYqSeNBBpqzUM3aTcZ22Nw5IgiISEFDw0CO_vguI1Ctu0uTQjCKKxr73229RyvowD6JlEC1eW4oaybncMbFGjy9o11KBKtltGKc12jKCOK9ARCEDooSoqp2MUUmqz1TUaMc4R5UiukUg0TKDmEBEa6oMkwKxxmkdAjxVFFFBSrAZHh333-n9O1mXkhvEmfgcpMsAz1pjNjpIFgFewWd9PA-lWsPbV_j_qqfpX8_1qw5wdmVsEvWf42tyj_IhkR0zrc_k7q4zim04DZJln82dkIL6L3T3_kJ5ZUXl01gYo1xAqLPabJRcK6o1ErJRlMJDH0QFDyughjVSlNTelquNosYqgezOuNyPpmvaMDiutSy4rAhHDZfEoGAc1bLQxjYN1CBI8hnaIxZPguTBGwc1FOB0S1QRJymkjrx2YYUgHa0LUtcKBJIIBdP7oycqjDq4Qvo35NU7st-GDEH2CLQ5Ygl2rjnfdmFfj1BQKUJ7lExwuJ25MG5juo4FHONLN9XW6EIUTYIL6zwM7k65fuvQ6TR7i5tNCGrOM_j04Z3CDnDuA45PnUdQbzNY_cZv38vp8gom_6W1LlgH8p_o8tDdihNA-y8k2mfXlzP-_2P-VSzcRHwzhieeOfPCjqI1tI1pRxcgCTCFSS1hLFZsT-sPkgmTS7EFcWcneXvAraD7Da2M4yl4OIo6bGiA-zg-_v7ysMh_W9w_PSC6p5V1gh4mKyWlgYdL9A4K-Am0-1f3YKUjGaIgRPixWPhCnH89_kH5k9xRBYwZVpsNhBen0XRycvxmAYDpVhYG4Okp7wmTy_WbfAdMZcsQKPgipOtAG6A0IL_VbJqkcQyAWeEI4yJKizgrgOQK7wDYZR2avblhSdeJ5eKdq4Rj9I2rNZLNkd6HDp1L_lZGUADqoejstESjGAPKaqovuMa4tqGq9aP_4IjoVcLKGI6HfwY7sR5VeS-ey80BetS90LWzA2MBv5g2VIGwl3WzHl3bMvH4ZMpbObVr6cJKFh-fF3__6RxeqJk4dUqspyi6N4pUpjjCqaCwlpxZCADQqA0RBqQZgCHJI4f7kyWTOTNNb-Z7I4-OwPrG3gRP_STlPqYbj0AKSY4vPJo4PpYXJNfc0lPZXuWbRfOR4bH2fzfZ2Qy-6NJtwV4eXovVE7TYefuePR_Mj6b_fMuAsSeoY4J1sPwUBVwP-KNKwRS7S0ce4Hv43FxH_Ba_ex_fwvNXbhHiw7OaxV9k9oNbBE6YqLitXY1zorrCN7Q9NcMTPawbgy7Wt4Whiif7Gfz1UWys8Qw5rOUgyo7ncPpM9g-cdr7-fsl9Kawn2EENmP-kdXYFagu9Oq4Yp3mz9vCst-vaE99Y6e8kZxPnw9OifKuJjzDqWwpUq1jDoBmm9RQC3fQ91AiI3TWRE0M1nCgrPgNIZhMaRSQZV3U5zkoS1-NyimmFp2OaYjyJapJVKU5mAKXs6m64AihUUhgYSgdS76kClkE7YJw1FVQRx-jlAdDU2K9fAZhugRp_LqRBHREWVuIB7RQzhorrm-fF96ieJ3WWZGRkmOF0DngaWD9dDtfbAYYOwX4fAoYuxtqhArYZ3C2FZpV2oZz3XYDxvy0rPLKKz396BTCtrd8BaTqJJqN2Xs9wNsYE42k2HWdJMyFJPCtpWaUliWJSjjgpKdcuN0hqxOZuZUQpjiIcj9MshLekiSezMknGJW4yuAfQjjAeejKDsRmpuY-htGvtLglABfp8CLmytaB0sE-saaWa31PxCQoy8uHOfaz_AJpyykA">