<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/79604>79604</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Add support for distributed ThinLTO options to `wasm-ld` driver
        </td>
    </tr>

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

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

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

<pre>
    The Wasm Driver for LLD seems to be missing options related to distributed ThinLTO.

https://gist.github.com/MaskRay/24f4e2eed208b9d8b0a3752575a665d4#distributed-thinlto may be a good reference.

We are looking to add ThinLTO support to Bazel / Emscripten. `wasm-ld` appears to be missing flags related specifically to _distributed_ ThinLTO. These flags appear to be used for e.g. mapping index files to objects. 

See https://reviews.llvm.org/D46034 for an example of some options added to the ELF driver.

Similarly, https://reviews.llvm.org/D64461 and https://reviews.llvm.org/D64542 have implementations for COFF.

The set of flags that we expect are:

```
--thinlto-index-only=
--thinlto-emit-imports-files
--thinlto-prefix-replace=
```
Also missing but not sure if related:
```
--obj-path=
```

+cc: @sbc100 @walkingeyerobot @googlewalt
</pre>
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