This reinstates part of the hack removed in r233223, by special
casing sse4 as part of the feature additions. The notable change
here is that we consider it only as part of setting the SSE level
and not as part of the actual target features set which handles
setting the rest of the masks.
llvm-svn: 241130
using a string map to canonicalize. Fix up a couple of testcases
that needed changing since we are no longer simply appending features
to the list, but all of their mask dependencies as well.
llvm-svn: 241129
Right now we're ignoring the fpmath attribute since there's no
backend support for a feature like this and to do so would require
checking the validity of the strings and doing general subtarget
feature parsing of valid and invalid features with the target
attribute feature.
llvm-svn: 239582
Modeled after the gcc attribute of the same name, this feature
allows source level annotations to correspond to backend code
generation. In llvm particular parlance, this allows the adding
of subtarget features and changing the cpu for a particular function
based on source level hints.
This has been added into the existing support for function level
attributes without particular verification for any target outside
of whether or not the backend will support the features/cpu given
(similar to section, etc).
llvm-svn: 239579