<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/75956>75956</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc] LIBC_INLINE_ASM pessimizes asm statements that are not implicitly volatile
        </td>
    </tr>

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

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

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

<pre>
    why do we have LIBC_INLINE_ASM? Throwing volatile on every asm is a pessimization. It generally prevents CSE which is bad.

> asm statements that have no output operands and asm goto statements, are implicitly volatile.

https://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Volatile

We're pretty inconsistent in our use of `asm` vs `__asm__` (and same with `__volatile__`).  We should clean all that up and just use `asm` then explicitly mark cases where we need `volatile`.

Putting volatile around everything is great for avoiding compiler bugs from 20 year old compilers, which we don't support.

Putting __ prefix+suffix also doesn't seem necessary.
</pre>
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