<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>Issue</th>
<td>
<a href=https://github.com/llvm/llvm-project/issues/100115>100115</a>
</td>
</tr>
<tr>
<th>Summary</th>
<td>
[AMDGPU] Assertion failure in MachineLICM when using llvm.amdgcn.update.dpp.i64
</td>
</tr>
<tr>
<th>Labels</th>
<td>
backend:AMDGPU
</td>
</tr>
<tr>
<th>Assignees</th>
<td>
</td>
</tr>
<tr>
<th>Reporter</th>
<td>
jayfoad
</td>
</tr>
</table>
<pre>
With this [test case](https://github.com/user-attachments/files/16349068/r.txt) I get:
```
$ llc -mtriple=amdgcn -mcpu=gfx1100 -filetype=null r.txt
llc: /home/jayfoad2/git/llvm-project/llvm/lib/CodeGen/MachineLoopInfo.cpp:294: bool llvm::MachineLoop::isLoopInvariant(llvm::MachineInstr &, const llvm::Register) const: Assertion `MRI->getVRegDef(Reg) && "Machine instr not mapped for this vreg?!"' failed.
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace.
```
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJycU0GPpDYT_TXFpdQIytDdHDiww7BqaUdazacvORtTgDfGRraZ7Pz7CLpHmShRDpGQLOOq96pevZIh6Mky11B-gbJN5BZn5-sf8n10ckh6N7zXv-o4Y5x1QCi_RA4RlQwMZQt0nWNcA4gGqAPqJh3nrU-VW4C6LbA_yRilmhe2MQB1oza8n_lZFFV2vgJ1Po0_I1CFN5w47khZC1kD5-zx3a9UoDEKT0v0ejUMopXLMCmLp0WtG4h2Gn_meZbhaeeI7-seYjdj8E5woBijQDQI1M1uYaDu0SbdSwfqjHlbTqt3P1h9XPdD90Ddkxv4K1ug7kWqWVv-5tx6s6NL1bqCaKgqdvTeOYNHomhANJ9i7z90uOe9Sa-ljUDXvwXfbIgegc5AT6icDfET4CtPOkT2u2bH207ahMA-amcRztnL6-0E4nni-MsrTy2PQNdXnvaEA_OMQPSgQn1wWRdxkevKA47O34f95nkC0QHlQAR0wVFqw0N61_L7t-fmf88Ytn7RESX224SeV-cjRof_YosPTf-qtA5hO6yB0g6orTLbwBhnRuVlmLGX6rfopeL0H_2RDLUYKlHJhOv8QvlFVHmZJ3NdXK_DUJG4cCVGKUiovLrIsrzmRU6yFImuKaMiu5DIqSSRpyobxktZVOrClFdnhiLjRWqT7hWnzk_JUWudZ1mel4mRPZtwrA_RXiXbAUTTvLRfv_9_F65sE18f3fbbFKDIjA4x_IkWdTTH-j1SyvbTNHfJN79PCT-MdHt6wd9ntrgFbafDGOl9F9JtHWTkdFjXVJ-LZPOm_u-DePT3VtMfAQAA__9j6EzY">