Question:
Y'all wanna see an excessively cute trick LLVM's optimizer can do?
Swift String contains roughly this method:
```
func _fastCStringContents() -> UnsafePointer<UInt8> {
if isASCII {
return contentsPointer
}
return nil
}
```
Where `isASCII` is defined as `(flags & 0x8000_0000_0000_0000) != 0`
Would you expect this to generate (solution in reply)
