[LLVMdev] some thoughts on the semantics of !fpmath

[Rafael Espíndola]

> It also has the problem that there's nothing preventing a
> pass like GVN from merging a !fpmath-decorated operation with an
> undecorated operation, and nothing requiring it to strip
> the !fpmath tag when it does so. (This is a general problem
> with LLVM metadata semantics.)

Can it? My impression from the last discussion on alias analysis is
that a pass can drop metadata it doesn't know, but it cannot ignore
it, so GVN would have to drop the metadata in this case.

> Dan
>

Cheers,
Rafael