<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/84178>84178</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Significant Increase in binary size and stack usage with clang 18.x
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

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

<pre>
    Greetings,

I've encountered a significant change in the behavior of `clang`'s `LLVM-IR` emission between versions, specifically when comparing the output of `clang` **17.0.1** with the **trunk** version for the `RISC-V rv32gc` target. The `IR` and the resultant `ELF` file sizes show a marked increase in the `.text` section size, with a difference of approximately 1200 bytes (from `0005e8` to `000a88`).

This issue is not confined to the `RISC-V` target alone. I have observed a similar pattern with a fork of the `llvm-project` (updated to the `release/18.x` branch two days ago) for our custom backend.

Furthermore, it appears that the `clang` version **18.x** and later are utilizing significantly more stack space, which has led to stack overflow errors in our testing environment (having just 2K of RAM).

For reference and further examination, I have provided an example here: https://godbolt.org/z/qeTae411h.

Could there have been changes in `clang`'s optimization strategies or `IR` emission patterns from version **17.0.1** to the `trunk` that might explain these observations? Any insights or suggestions on mitigating these issues (perhaps some new compilation flags)?
</pre>
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