[llvm] [mlir] [mlir][OpenMP] Add __atomic_store to AtomicInfo (PR #121055)

[via llvm-commits]

NimishMishra wrote:

Hi @tblah     

    It seems that just adding a convert in fortran is not sufficient. I added an explicit convert, and somewhere down the line, it gets removed, and I can still reproduce the segfault


FIR: 
```
omp.parallel {
      %15 = fir.convert %5 : (!fir.ref<complex<f64>>) -> !fir.ref<complex<f32>>
      omp.atomic.read %3 = %15 : !fir.ref<complex<f32>>, !fir.ref<complex<f32>>, complex<f64>
      omp.terminator
    }
```

Corresponding LLVM Dialect
```
    omp.parallel {
      omp.atomic.read %1 = %6 : !llvm.ptr, !llvm.ptr, !llvm.struct<(f64, f64)>
      omp.terminator
    }
```

  I'm investigating where the issue is.

https://github.com/llvm/llvm-project/pull/121055