[llvm] [X86] Try Folding icmp of v8i32 -> fcmp of v8f32 on AVX (PR #82290)

[via llvm-commits]

goldsteinn wrote:

> Any luck with the remaining regressions?

Most of the regressions are fixed with #84360, the only outstanding one
is when we later simplify to `xmm` w/ demandedelts in which case we
have converted from int -> float without any benefit. For example:
https://github.com/llvm/llvm-project/pull/84360/files#diff-ec93308ebc948e632bea97e65a5aeedc4342aab5fa49d2c4a43be983131fba47R17

Thats tough to get around, as float -> int is much more difficult to
pull off.

https://github.com/llvm/llvm-project/pull/82290