MFC r345703:
Fix initial exec TLS mode for dynamically loaded shared objects.

MFC r334505:
Don't export _end on arm64 and riscv.

MFC r312703:

Fix the error value we write in cerror. __error returns an int *, however
we were writing a 64 bit value meaning the 32 bits after this would be
trashed.

MFC r314556-r314558

r314556:
Correct MDSRCS use in <arch>/string/Makefile.inc.

- Remove .c files which duplicate entries in MISRCS.
- Use the same, less merge conflict prone style in all cases.
- Use MDSRCS for mips (.c and .S files both ended up in SRCS).
- Remove pointless sparc64 Makefile.inc.
- Remove uninformative foreign VCS ID entries.

Reviewed by: emaste, imp, jhb
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9841

r314557:
Correct an misunderstanding of MDSRCS.

MDSRCS it intended to allow assembly versions of funtions with C
implementations listed in MISRCS. The selection of the correct
machdep_ldis?.c for a given architecture does not follow this pattern
and the file should be added to SRCS directly.

Reviewed by: emaste, imp, jhb
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9841

r314558:
Garbage collect unused gdtoa related files on mips.

Reviewed by: emase, imp, jhb
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9841

MFC r304285:
Implement userspace gettimeofday(2) with HPET timecounter.

MFC r305015:
Remove commented out mention of ptrace.S.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Replace use of the pipe(2) system call with pipe2(2) with a zero flags
value.

This eliminates the need for machine dependant assembly wrappers for
pipe(2).

It also make passing an invalid address to pipe(2) return EFAULT rather
than triggering a segfault. Document this behavior (which was already
true for pipe2(2), but undocumented).

Reviewed by: andrew
Approved by: re (gjb)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D6815

Remove brk and sbrk from arm64. They were defined in The Single UNIX
Specification, Version 2, but marked as legacy, and have been removed from
later specifications. After 12 years it is time to remove them from new
architectures when the main use for sbrk is an invalid method to attempt
to find how much memory has been allocated from malloc.

There are a few places in the tree that still call sbrk, however they are
not used on arm64. They will need to be fixed to cross build from arm64,
but these will be fixed in a follow up commit.

Old copies of binutils from ports called into sbrk, however this has been
fixed around 6 weeks ago. It is advised to update binutils on arm64 before
installing a world that includes this change.

Reviewed by: brooks, emaste
Obtained from: brooks
Relnotes: yes
Sponsored by: ABT Systems Ltd
Differential Revision: https://reviews.freebsd.org/D6464

arm64 libc: hide .cerror, .curbrk, .minbrk for WITHOUT_SYMVER

When symver is in use these are hidden because they're not listed in
the Symbol.map. Add an explicit .hidden so they are also hidden in the
WITHOUT_SYMVER case.

Reviewed by: andrew
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5775

Disable support for compat syscalls on arm64. These symbols were never
shipped since arm64 exists only on 11+.

Submitted by: brooks
Reviewed by: emaste, imp

libc: stop exporting curbrk and minbrk in the private namespace

They are not used anywhere else in the base system and are an internal
implementation detail that does not need to be exposed.

Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5728

Add support for usermode (vdso-like) gettimeofday(2) and
clock_gettime(2) on ARMv7 and ARMv8 systems which have architectural
generic timer hardware. It is similar how the RDTSC timer is used in
userspace on x86.

Fix a permission problem where generic timer access from EL0 (or
userspace on v7) was not properly initialized on APs.

For ARMv7, mark the stack non-executable. The shared page is added for
all arms (including ARMv8 64bit), and the signal trampoline code is
moved to the page.

Reviewed by: andrew
Discussed with: emaste, mmel
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D4209

Add include for declaration of _set_tp(). Eliminates -Wmissing-prototypes warnings.

Add the definitions of __infinity and __nan.

Add support for makecontext. This supports up to 8 arguments as this
simplifies the code, these can be passed in registers.

Obtained from: ABT Systems Ltd
Sponsored by: The FreeBSD Foundation

Add hton and ntoh to the arm64 Symbols.map file, they exist but were not
exported.

Cleanup brk and sbrk to use the same code to find curbrk and minbrk when
both compiling for PIC and non-PIC.

Sponsored by: ABT Systems Ltd

Implement fpgetmask, it's needed by Python.

Approved by: ABT Systems Ltd
Sponsored by: The FreeBSD Foundation

Export __flt_rounds from the arm64 libc.so

Implement fpsetmask. Some third-party software makes use of it, for example
perl.

Obtained from: ABT Systems Ltd
Sponsored by: The FreeBSD Foundation

Set the alignment of the setjmp magic values correctly. The alignment needs
to be before the lavel, otherwise an extra word may be added between the
label and the data.

Obtained from: ABT Systems Ltd
Sponsored by: The FReeBSD Foundation

Set the correct register when calling sigprocmask in longjmp.

Submitted by: Patrick Wildt <patrick@bitrig.org>
Obtained from: drahn@bitrig.org

Add fabs() to arm64 libc

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D2532

Add the start of libc and libstand for arm64. Not all of the machine
dependent functions have been implemented, but this is enough for world.

Differential Revision: https://reviews.freebsd.org/D2132
Reviewed by: emaste
Sponsored by: The FreeBSD Foundation

Start to import support for the AArch64 architecture from ARM. This change
only adds support for kernel-toolchain, however it is expected further
changes to add kernel and userland support will be committed as they are
reviewed.

As our copy of binutils is too old the devel/aarch64-binutils port needs
to be installed to pull in a linker.

To build either TARGET needs to be set to arm64, or TARGET_ARCH set to
aarch64. The latter is set so uname -p will return aarch64 as existing
third party software expects this.

Differential Revision: https://reviews.freebsd.org/D2005
Relnotes: Yes
Sponsored by: The FreeBSD Foundation