LLONG_MAX is uniform for all archs we support and plenty of header and
code level logic assumes it is, so it does not make sense for limits.h
bits mechanism to pretend it's variable.
LONG_BIT can be defined in terms of LONG_MAX; there's no reason to put
it in bits.
by moving LONG_MAX definition to __LONG_MAX in alltypes.h and moving
LLONG_MAX out of bits, there are now no plain-C limits that are
defined in the bits header, so the bits header only needs to be
included in the POSIX or extended profiles. this allows the feature
test macro logic to be removed from the bits header, facilitating a
long-term goal of getting such logic out of bits.
having __LONG_MAX in alltypes.h will allow further generalization of
headers.
archs without a constant PAGESIZE no longer need bits/limits.h at all.
aarch64, arm, mips, mips64, mipsn32, powerpc, powerpc64 and sh have
cpu feature bits defined in linux for AT_HWCAP auxv entry, so expose
those in sys/auxv.h
it seems the mips hwcaps were never exposed to userspace neither
by linux nor by glibc, but that's most likely an oversight.
all bits headers that were identical for a number of 'clean' archs are
moved to the new arch/generic tree. in addition, a few headers that
differed only cosmetically from the new generic version are removed.
additional deduplication may be possible in mman.h and in several
headers (limits.h, posix.h, stdint.h) that mostly depend on whether
the arch is 32- or 64-bit, but they are left alone for now because
greater gains are likely possible with more invasive changes to header
logic, which is beyond the scope of this commit.
This adds complete aarch64 target support including bigendian subarch.
Some of the long double math functions are known to be broken otherwise
interfaces should be fully functional, but at this point consider this
port experimental.
Initial work on this port was done by Sireesh Tripurari and Kevin Bortis.
apparently some other archs have sys/io.h and should not break just
because they don't have the x86 port io functions. provide a blank
bits/io.h everywhere for now.