[clang] [llvm] [CIR][X86] Implement lowering for sqrt builtins (PR #169310)

[Andy Kaylor via llvm-commits]

andykaylor wrote:

Note that placeholders for the target-independent sqrt builtins are being add in https://github.com/llvm/llvm-project/pull/169424. You may want to wait for that to land before implementing those.

https://github.com/llvm/llvm-project/pull/169310