<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/107891>107891</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [RISC-V] Miscompile with RISC-V Vector Peephole Optimization
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          patrick-rivos
      </td>
    </tr>
</table>

<pre>
    Testcase:
```c
long b;
long c[5];
int d[25];
int main() {
  for (long g = 3; g < b + 23; g += 4)
    d[g] = g * g ?: c[g];
  __builtin_printf("%u\n", d[3]);
}
```
Commands:
```
> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/build-llvm-linux/bin/clang -march=rv64gcv -O3 red.c -o user-config.out -fsigned-char -fno-strict-aliasing -fwrapv
> QEMU_CPU=rv64,vlen=128,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true timeout --verbose -k 0.1 4 /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64 user-config.out
4294967295

> /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/build-llvm-linux/bin/clang -march=rv64gcv -O3 red.c -o user-config.out -fsigned-char -fno-strict-aliasing -fwrapv -mllvm -opt-bisect-limit=131
...
BISECT: running pass (131) RISC-V DAG->DAG Pattern Instruction Selection on function (main)
BISECT: NOT running pass (132) RISC-V Vector Peephole Optimization on function (main)
...
> QEMU_CPU=rv64,vlen=128,rvv_ta_all_1s=true,rvv_ma_all_1s=true,v=true,vext_spec=v1.0,zve32f=true,zve32x=true,zve64d=true,zve64f=true,zve64x=true timeout --verbose -k 0.1 4 /scratch/tc-testing/tc-compiler-fuzz-trunk/build-gcv/bin/qemu-riscv64 user-config.out
9
```

-opt-bisect-limit points to `RISC-V Vector Peephole Optimization`

Found via fuzzer. First detected on a build from the 6th of September.
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsVUtv4zYQ_jX0ZUBBpl7mQQfbihY5bJM22b0aFEVJbCRSJSklza8vRDmPOgt0gZwKLGBY8w057xkOs1a2SogcJQeUFBs2uU6bfGTOSP6AjZy13VS6_ju_F9ZxZgWK9igsULhHabj--Ip7rVqoUHR4BzlKDglKileuVA5qlBzIB-7ApEJkhwgFlJ35AI02gMjOK2sBRQVEKDp48ggVIHIA8sIhh-U8RoS-SIO31aKk8KLLnb2XLVG09861790AOJ2qSfZOqtNopHKNd4ggkkwoOSpPHr3OaJEj9FUUZcVFVlZ41MPAVG0_Zu0MoytApLTcMMc7RErHsRPWSdWugOthlL0wuJmen7Ezk3pApFy8rHHL51e67-cB91JNTwtrSWXJe6ZawAMzvENRYeY0bvkM-CYCI-qAA9YwWWEw16qRbaAnB7jx_VBj3jEDuFEa26UVHGa9ZFYuCptHw8b5zf_fr75-Ox1vv51tIHKce6FQVGyX7B3NPJ8cO7G-P20tigpnJnFmDx_Z8ztSPLmTHQVHUTFvgxCR4_MsItK8XfH46V84jesL3Fzgl_vg5CB80HgWptJWAH6AMNhC_Oma-AL8JYYJG2n5nMaXmV7TFxMa0zQjNDmn83_eFICHxSZgPTpcSSu4w70cpFu6Idqu4QVBsBKH67ur4_0yimZSalEzMmuXeV_uEgp_XN8d8Xco9l8wiq6K_Re4Zc4Jo-BaWWcm7qRWcCd6sVJaQTOplUZktz4p9NLYbzf3PzBI3hn8LrjTBm6FGDvdC7gZnRzkM_tPI6-h_ZqLT80F_fFj6f8_9BaMWipnwWlAafgTJbxQWOpJ1TBLBovfwgRQSmMd1MIJ7kS9VJyBDwMaowdwnYDUdaAbuBOjE0MlTLCp86imEWUbkW8zktAwpFG46XKacsIS0USEJtuM0yzlvM6yhtdV2kS7ZiNzEpI4pCHdpklCaFAz2lRZk7JmF_OMUhSHYmCyD5bZCrRpN9LaSeTbMNvR7aZnleit3-CEKPEI_nRZVkmxMbl_BKqptSgOe2mdfVPjpOv96l-TtuzJr9KeywiP0nU_MxGbyfR559zotxwpESlb6bqpCrgeECkXc-cPHo3-U3CHSOmdtIiU5yjmnPwTAAD__8uPqWU">