<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/80057>80057</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [18 regression] UNREACHABLE executed at /builddir/build/BUILD/llvm-project-release-18.x/llvm/utils/TableGen/PredicateExpander.cpp:399!
        </td>
    </tr>

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

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

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

<pre>
    Crosscompiling LLVM (Host: `aarch64-linux-gnu`, Target: `rv64imafdc-linux-gnu`) from the release/18.x branch, with `llvm-tblgen` from release/18.x branch 4 days ago, results in

```
FAILED: lib/Target/RISCV/RISCVGenMacroFusion.inc /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/build/lib/Target/RISCV/RISCVGenMacroFusion.inc
cd /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/build && /usr/bin/llvm-tblgen -gen-macro-fusion-pred -I /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/lib/Target/RISCV -I/home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/build/include -I/home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/include -I /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/lib/Target /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/lib/Target/RISCV/RISCV.td --write-if-changed -o lib/Target/RISCV/RISCVGenMacroFusion.inc -d lib/Target/RISCV/RISCVGenMacroFusion.inc.d
No known rules to expand this MCInstPredicate
UNREACHABLE executed at /builddir/build/BUILD/llvm-project-release-18.x/llvm/utils/TableGen/PredicateExpander.cpp:399!
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
Stack dump:
0.      Program arguments: /usr/bin/llvm-tblgen -gen-macro-fusion-pred -I /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/lib/Target/RISCV -I/home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/build/include -I/home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/include -I /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/lib/Target /home/bero/crossbuild/packages/llvm/BUILD/llvm-project-release-18.x/llvm/lib/Target/RISCV/RISCV.td --write-if-changed -o lib/Target/RISCV/RISCVGenMacroFusion.inc -d lib/Target/RISCV/RISCVGenMacroFusion.inc.d
 #0 0x0000aaaaada4cf48 (/usr/bin/llvm-tblgen+0x3dcf48)
 #1 0x0000aaaaada4c9a4 (/usr/bin/llvm-tblgen+0x3dc9a4)
 #2 0x0000ffff96a667bc (linux-vdso.so.1+0x7bc)
 #3 0x0000ffff9645df98 (/lib64/libc.so.6+0x8df98)
 #4 0x0000ffff9641452c gsignal (/lib64/libc.so.6+0x4452c)
 #5 0x0000ffff96400280 abort (/lib64/libc.so.6+0x30280)
 #6 0x0000aaaaada25d1c (/usr/bin/llvm-tblgen+0x3b5d1c)
 #7 0x0000aaaaad983114 (/usr/bin/llvm-tblgen+0x313114)
 #8 0x0000aaaaad9823a4 (/usr/bin/llvm-tblgen+0x3123a4)
 #9 0x0000aaaaad981f54 (/usr/bin/llvm-tblgen+0x311f54)
#10 0x0000aaaaad982e68 (/usr/bin/llvm-tblgen+0x312e68)
#11 0x0000aaaaad981fb0 (/usr/bin/llvm-tblgen+0x311fb0)
#12 0x0000aaaaad982e68 (/usr/bin/llvm-tblgen+0x312e68)
#13 0x0000aaaaad9997d4 (/usr/bin/llvm-tblgen+0x3297d4)
#14 0x0000aaaaad998578 (/usr/bin/llvm-tblgen+0x328578)
#15 0x0000aaaaad9f3a54 (/usr/bin/llvm-tblgen+0x383a54)
#16 0x0000ffff96400944 (/lib64/libc.so.6+0x30944)
#17 0x0000ffff96400a18 __libc_start_main (/lib64/libc.so.6+0x30a18)
#18 0x0000aaaaad760db0 (/usr/bin/llvm-tblgen+0xf0db0)
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsl19v3CgXxj8Nc4NsAcb_LuZikozbkaZV1LztbYQB27yxzQhwMv32KzwzTZjttpPVplqtOopi2XrOj4dzDhgza1U7SrkE6RVIbxZscp02y1oa3atx2i9qLb4ur422luthp3o1tnC7_fIBAlK819aBZAVBhhgzvMtoNAdF7TiBDAFyDf_HTCtPIvOYUTWwRvAzXQkbowfoOgmN7CWzEpAKF_Ee1oaNvPOkJ-U6D-n7xyFydd_KEWToEPjdIEihYF8tZK328UbaqXcWqhGgG4BWx_8ZOv7Nt9Vqs13feLu9qgGpjvZJ9Wlzd_3ldH0nxw-MG11NVukxViOHgFSdHrwDnzpAKu5TVk-qF4BUO8YfWCstIJW3D0h19XmzvTneRjuj_y-5i47TiPwkPOkY_Torh4lw8XaWICAZIJkfYLLGP1XjKe5QGBi1cowGbyxqZmfRzkgBo82buDpKv5cnGG3esjRq5P0k5BuNcpQ-D_Krsverq3S6xk7AKHoyyslINRHv2Nj6ttGvXY6ReGVELA7r5qOGD6N-GqGZemmh01Dud2wU0HXKwg_Xm9G6WyOF4szJQ8jnj5_Wq-v3q6vtGsq95JOTArI5h3PChDIvOuYVmZqc6u08h7qX76RfY9-GXs-upIn5bgeSVVKWgOCDn9vtenW3hnaqB-Ugg_XUQiN32jg_nc65nQXJCpAKkKpVrpvqmOvhRYFeOPPdZ-00lxr6NJx60W_V3DDbwZrxB2cYl_Fh-DvH-AMU0-B9HR6hGM6_W6NbwwbITDsNcnR2fi_83kV-7yL_sV0EApIgiPYIIcT8TzDKG1r4Q9Nf9zsgV2ifCC8EpHwm4XNSyehlpJLRgESOpKZpmjJjWZbX_uhSHE5jj8Lq2OoYz-F5zYPYJIilqWjK03x6VWf0cOUekM2AwisCBA0RmKaEw9YfQFn_QxT1ygCVhiiESIEgq_0m9yNQ4nUBKAuTS1KB-SXJrb0wIOUBqSwSjC8qE_bCgFSckUhyWcGxFwak8oyEm_Qykhd-I_keROeeZHZRO2MvDEj4T55qdKGnGgUk8o95SkJSWebiojwRLwxI9IxUpPlFnogXBqQ0JDUJu6x2hRcGpOx8sZSU_mSZlDRE5OcIhgt4f-_D7q1jxt0PTI0_gTIczjDs8zxD4qJOaLzuGXT6gluIZSLKpGQLucQ5yjKaY1ouuiXLUiJRSmuGirzASZ4ksmxQRkXCeJrThVoSRCjCCSIoKVEZC4obWnKEKacJJjWgSA5M9bG3EmvTLuZT0bJAKM0XPatlb09f0GY5-62n1gKKemWdfQ5zyvXztzYuoJGtkda_OkB6A_89p8jFZPrl3z8mzjn5IwAA__-bPAaw">