Integrate LLVM at llvm/llvm-project@12d04ce9569e
Integrate LLVM at llvm/llvm-project@12d04ce9569e

Updates LLVM usage to match
[12d04ce9569e](https://github.com/llvm/llvm-project/commit/12d04ce9569e)

PiperOrigin-RevId: 384681697

google-research/structured-additive-IR,google-research/structured-additive-IR