Summary:
Some targets support denormals as floating point exceptions. This is
provided as an extension in the GNU headers as __FE_DENORM.
This provides it in our headers, however I'm unsure if we should make it
internal or external. I do not think it should be in all exception as it
doesn't represent an exceptional behavior as far as the standard is
concerned, but I'm not an expert.
Towards the goal of getting `ninja libc-lint` back to green, fix the numerous
instances of:
warning: header guard does not follow preferred style [llvm-header-guard]
This is because many of our header guards start with `__LLVM` rather than
`LLVM`.
To filter just these warnings:
$ ninja -k2000 libc-lint 2>&1 | grep llvm-header-guard
To automatically apply fixits:
$ find libc/src libc/include libc/test -name \*.h | \
xargs -n1 -I {} clang-tidy {} -p build/compile_commands.json \
-checks='-*,llvm-header-guard' --fix --quiet
Some manual cleanup is still necessary as headers that were missing header
guards outright will have them inserted before the license block (we prefer
them after).
Fixing an issue with LLVM libc's fenv.h defined rounding mode macros
differently from system libc, making get_round() return different values from
fegetround(). Also letting math tests to skip rounding modes that cannot be
set. This should allow math tests to be run on platforms in which fenv.h is not
implemented yet.
This allows us to re-enable hermatic floating point tests in
https://reviews.llvm.org/D151123 and reverting https://reviews.llvm.org/D152742.
Reviewed By: jhuber6
Differential Revision: https://reviews.llvm.org/D152873
