Remove svn:mergeinfo from the releng/10.0 branch.

After branch creation from stable/10, the stable/10 branch mergeinfo
was moved to the root of the branch.

Since there have not been any merges from stable/10 to releng/10.0
yet, we do not need to track any of the existing mergeinfo here.

Merges to releng/10.0 should now be done to the root of the branch.

For future branches during the release cycle, unless otherwise noted,
this change will be done as part of the stable/ and releng/ branch
creation.

Discussed with: peter
Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Don't use the pcs attribute on compilers that don't support it. We can
revert this when we stop supporting old versions of gcc.

Add a newline at the end of the file to stop gcc from complaining

Import compiler-rt r172839.

This brings in __aeabi_lcmp and __aeabi_ulcmp. It also fixes the spelling
of __aeabi_f2lz. Both changes originated on the arm_eabi project branch.

Import compiler-rt r160957.

This is mostly a no-op other than for ARM where it adds missing
__aeabi_mem* and __aeabi_*divmod functions. Even on ARM these will remain
unused until the rest of the ARM EABI code is merged.

Regenerate after r235388.

- Get rid of debugging support in order to get rid of the V8-specific C
compiler frame size used there so this whole thing is V8/V9-agnostic.
- Use 32-bit function alignment as GCC does when using UltraSPARC I or
higher optimizations.
- Don't waste delay slots when possible.

Unfortunately, this still doesn't make libcompiler_rt a viable replacement
for libgcc on sparc64 though as once installed instead, buildworld times
increase by nearly 60% (which isn't related to these assembler functions).

Add SPARC64 version of div/mod written in assembly.

This version is similar to the code shipped with libgcc. It is based on
the code from the SPARC64 architecture manual, provided without any
restrictions.

Tested by: flo@

Add a workaround to prevent endless recursion in compiler-rt.

SPARC and MIPS CPUs don't have special instructions to count
leading/trailing zeroes. The compiler-rt library provides fallback
rountines for these. The 64-bit routines, __clzdi2 and __ctzdi2, are
implemented as simple wrappers around the compiler built-in
__builtin_clz(), assuming these will expand to either 32-bit
CPU instructions or calls to __clzsi2 and __ctzsi2.

Unfortunately, our GCC 4.2 probably thinks that because the operand is
stored in a 64-bit register, it might just be a better idea to invoke
its 64-bit equivalent, simply resulting into endless recursion. Fix this
by defining __builtin_clz and __builtin_ctz to __clzsi2 and __ctzsi2
explicitly.

Import compiler-rt r147467.

The compiler-rt shipped with FreeBSD is now based on unmodified upstream
sources.

Upgrade libcompiler_rt to upstream revision 147390.

This version of libcompiler_rt adds support for __mulo[sdt]i4(), which
computes a multiply and its overflow flag. There are also a lot of
cleanup fixes to headers that don't really affect us.

Updating to this revision should make it a bit easier to contribute
changes back to the LLVM developers.

With retirement of cpumask_t and usage of cpuset_t for representing a
mask of CPUs, pc_other_cpus and pc_cpumask become highly inefficient.

Remove them and replace their usage with custom pc_cpuid magic (as,
atm, pc_cpumask can be easilly represented by (1 << pc_cpuid) and
pc_other_cpus by (all_cpus & ~(1 << pc_cpuid))).

This change is not targeted for MFC because of struct pcpu members
removal and dependency by cpumask_t retirement.

MD review by: marcel, marius, alc
Tested by: pluknet
MD testing by: marcel, marius, gonzo, andreast

etire the cpumask_t type and replace it with cpuset_t usage.

This is intended to fix the bug where cpu mask objects are
capped to 32. MAXCPU, then, can now arbitrarely bumped to whatever
value. Anyway, as long as several structures in the kernel are
statically allocated and sized as MAXCPU, it is suggested to keep it
as low as possible for the time being.

Technical notes on this commit itself:
- More functions to handle with cpuset_t objects are introduced.
The most notable are cpusetobj_ffs() (which calculates a ffs(3)
for a cpuset_t object), cpusetobj_strprint() (which prepares a string
representing a cpuset_t object) and cpusetobj_strscan() (which
creates a valid cpuset_t starting from a string representation).
- pc_cpumask and pc_other_cpus are target to be removed soon.
With the moving from cpumask_t to cpuset_t they are now inefficient
and not really useful. Anyway, for the time being, please note that
access to pcpu datas is protected by sched_pin() in order to avoid
migrating the CPU while reading more than one (possible) word
- Please note that size of cpuset_t objects may differ between kernel
and userland. While this is not directly related to the patch itself,
it is good to understand that concept and possibly use the patch
as a reference on how to deal with cpuset_t objects in userland, when
accessing kernland members.
- KTR_CPUMASK is changed and now is represented through a string, to be
set as the example reported in NOTES.

Please additively note that no MAXCPU is bumped in this patch, but
private testing has been done until to MAXCPU=128 on a real 8x8x2(htt)
machine (amd64).

Please note that the FreeBSD version is not yet bumped because of
the upcoming pcpu changes. However, note that this patch is not
targeted for MFC.

People to thank for the time spent on this patch:
- sbruno, pluknet and Nicholas Esborn (nick AT desert DOT net) tested
several revision of the patches and really helped in improving
stability of this work.
- marius fixed several bugs in the sparc64 implementation and reviewed
patches related to ktr.
- jeff and jhb discussed the basic approach followed.
- kib and marcel made targeted review on some specific part of the
patch.
- marius, art, nwhitehorn and andreast reviewed MD specific part of
the patch.
- marius, andreast, gonzo, nwhitehorn and jceel tested MD specific
implementations of the patch.
- Other people have made contributions on other patches that have been
already committed and have been listed separately.

Companies that should be mentioned for having participated at several
degrees:
- Yahoo! for having offered the machines used for testing on big
count of CPUs.
- The FreeBSD Foundation for having sponsored my devsummit attendance,
which has been instrumental.
- Sandvine for having offered offices and infrastructure during
development.

(I really hope I didn't forget anyone, if it happened I apologize in
advance).

Upgrade libcompiler_rt from revision 117047 to 132478.

It seems there have only been a small amount to the compiler-rt source
code in the mean time. I'd rather have the code in sync as much as
possible by the time we release 9.0. Changes:

- The libcompiler_rt library is now dual licensed under both the
University of Illinois "BSD-Like" license and the MIT license.

- Our local modifications for using .hidden instead of .private_extern
have been upstreamed, meaning our changes to lib/assembly.h can now be
reverted.

- A possible endless recursion in __modsi3() has been fixed.

- Support for ARM EABI has been added, but it has no effect on FreeBSD
(yet).

- The functions __udivmodsi4 and __divmodsi4 have been added.

Requested by: many, including bf@ and Pedro Giffuni

Set symbol visibility to hidden.

Not doing so may cause all sorts of random libraries to expose
libcompiler_rt's functions, which should of course not be done.

Discussed with: kan, kib

Import libcompiler_rt into HEAD and add Makefiles.

Obtained from: user/ed/compiler-rt

Import compiler-rt r117047.

Add a directory for compiler-rt to the vendor space.