A lot of attributes are essentially default target configuration, and we should only differ when there's a good reason to.
For the attributes we were already setting:
- the ptrauth and target CPU/feature attributes are taken care of by Clang
- I've updated the optsize/minsize attributes to the apparent intent
- I've left the frame-pointer override in place for now
Fixes rdar://63289339, which was caused by Swift's ptrauth IR attributes getting out of sync with Clang's.
For now these are underscored attributes, i.e. compiler internal attributes:
@_optimize(speed)
@_optimize(size)
@_optimize(none)
Those attributes override the command-line specified optimization mode for a specific function.
The @_optimize(none) attribute is equivalent to the already existing @_semantics("optimize.sil.never") attribute