[LLVMdev] [RFC] Integer Saturation Intrinsics

[David Chisnall]

On 15 Jan 2015, at 10:51, David Majnemer <david.majnemer at gmail.com> wrote:
> 
> I don't think this should be a flag on add.  Flags are designed such that the middle-end may be ignorant of them and nothing bad might happen, it is always safe to ignore or drop flags when doing so is convenient (for a concrete example, take a look at reassociate).

This is true of metadata, not of flags.  Consider the atomic memory order on loads and stores, for example.  It is definitely not safe for an optimiser to ignore these.

David