<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/144520>144520</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [RISCV] Enable loop vectorizer register pressure VF pruning again
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            backend:RISC-V
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
            lukel97
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          lukel97
      </td>
    </tr>
</table>

<pre>
    After https://github.com/llvm/llvm-project/pull/132190 we fixed the issue with spilling on https://godbolt.org/z/WcbWGooa4 since we were now pruning VFs that had too high a register pressure, even if `TTI::shouldMaximizeVectorBandwidth` was false.

However this caused some regressions on AArch64 so it was reverted back to only pruning when vector bandwidth was maximized in #141736. This causes the above link to spill again.

We should find a way to enable this pruning again on RISC-V, which may just be a matter of enabling `TTI::shouldMaximizeVectorBandwidth`. We'll need to double check that it doesn't actually cause more spilling in practice.
</pre>
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