a92e3df300
Lowering `math.powf` to `llvm.intr.powf` will result in `pow(x, 0) = 1`, even for `x=0`. When using the Math dialect expansion patterns, `pow(0, 0)` will result in `-nan`, however, This change adds two additional instructions to the lowering to ensure the `pow(x, 0)` case lowers to to `1` regardless of the value of `x`. Resolves https://github.com/llvm/llvm-project/issues/118945.