<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/63632>63632</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            error: couldn't allocate input reg for constraint 'r' on MIPS when building some wasm2c-generated code
        </td>
    </tr>

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

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

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

<pre>
    This is similar to #52638, but for floats.

Reduced C reproducer:
```
float a;
void foo() {
 __asm__("" :: "r"(a));
}
```
```
$ clang --target=mips64el-linux-gnuabi64 -c test.c
test.c:3:13: error: couldn't allocate input reg for constraint 'r'
    __asm__("" :: "r"(a));
 ^
1 error generated.
```
Reduced LLVM IR reproducer:
```
target triple = "mips64el-unknown-linux-gnuabi64"

define void @foo() {
  call void asm sideeffect "", "r,~{$1}"(float 0.000000e+00)
  ret void
}
```
```
$ llc test.ll
error: couldn't allocate input reg for constraint 'r'
```
</pre>
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