Copy stable/11@r303970 to releng/11.0 as part of the 11.0-RELEASE
cycle.

Prune svn:mergeinfo from the new branch, and rename it to RC1.

Update __FreeBSD_version.

Use the quarterly branch for the default FreeBSD.conf pkg(8) repo and
the dvd1.iso packages population.

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

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

Make armv6 hard float abi by default. Kill armv6hf.
Allow CPUTYPE=soft to build the current soft-float abi libraries.
Add UPDATING entry to announce this.

Approved by: re@ (gjb)

Revert a change that sneeked with 297619

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 cerror

i386 stopped exporting .cerror in r240152, and likewise for amd64 in
r240178. It is not used by other libraries on any platform, so apply
the same change to the remaining architectures.

Reviewed by: jhibbits, jilles
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5774

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

Do not compile ARMv6 instructions on ARMv4/v5. Although clang is fine
with mrrc, gcc is not. The disabled code is not executed on ARMv4
anyway.

Reported and reviewed by: ian
Sponsored by: The FreeBSD Foundation

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

Annotate arm userspace assembler sources stating their tolerance to
the non-executable stack.

Reviewed by: andrew
Sponsored by: The FreeBSD Foundation

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

Export the ARM __aeabi_mem* functions from libc, they are needed by the gcc
from ports as it doesn't include these in the copy of libgcc it installs
uses.

Obtained from: ABT Systems Ltd

Add the needed if-then instructions to build as Thumb-2.

Remove __ARM_EABI__ from more places in libc as this is the only ARM ABI
we support.

Use a register to set the cpsr bits. The ip register is safe to be changed
within all of these functions, and is only stored in some to correctly pad
the stack.

This will be needed to build as Thumb-2 as, unlike with ARM instructions,
the msr instruction only takes a register as the input.

Removed unused special fork() implementations.

The arm version hasn't been used in ages.

The mips version uses a valid, but pointless check of v1 and has been
unhooked from the build since r276630.

Differential Revision: https://reviews.freebsd.org/D2592
Reviewed by: emaste
Sponsored by: DARPA, AFRL

Teach bits of libc about Thumb. This adds the if-then instructions needed
to handle the ARM conditional execution.

While here fix a bug found by this in the hard-float code, cc is the
opposite of cs. The former is used for 'less than' in floating-point code
and is executed when the C (carry) bit is clear, the latter is used when
greater than, equal, or unordered, and is executed when the C bit is set.

Use the GOT_* macros to help simplify the code, these work with both pic
and non-pic code, and to build for Thumb.

The lseek(2), mmap(2), truncate(2), ftruncate(2), pread(2), and
pwrite(2) syscalls are wrapped to provide compatibility with pre-7.x
kernels which required padding before the off_t parameter. The
fcntl(2) contains compatibility code to handle kernels before the
struct flock was changed during the 8.x CURRENT development. The
shims were reasonable to allow easier revert to the older kernel at
that time.

Now, two or three major releases later, shims do not serve any
purpose. Such old kernels cannot handle current libc, so revert the
compatibility code.

Make padded syscalls support conditional under the COMPAT6 config
option. For COMPAT32, the syscalls were under COMPAT6 already.

Remove WITHOUT_SYSCALL_COMPAT build option, which only purpose was to
(partially) disable the removed shims.

Reviewed by: jhb, imp (previous versions)
Discussed with: peter
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

libc: Eliminate duplicate copies of __vdso_gettc.c

Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D2152

Remove duplicate copies of trivial getcontextx.c

Only i386 and amd64 provide a non-trivial __getcontextx(). Use a common
trivial implementation in gen/ for other architectures, rather than
copying the file to each MD subdirectory.

Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1472

Apparently more Makefiles use stuff from compiler-rt, so fix them up
too. (This did not show during a make universe, strangely.)

Switch to the ARM unified assembly language as the clang integrated as only
supports it. Binutils supports it when the ".syntax unified" directive
is set.

Sponsored by: ABT Systems Ltd

Add support for the __aeabi_c*cmp* functions. These are similar to the
existing functions with the exception they use the condition flags to
store the result.

Differential Revision: https://reviews.freebsd.org/D872
Silence from: current@ and numerics@
MFC after: 1 week

Clean up detection of hard-float ABIs. As with big-endian in r272368 we
can check against arm*hf*.

Remove MK_ARM_EABI, the armeb issues have been fixed. The code to support
the oabi is still in the tree, but it is expected this will be removed
as developers work on surrounding code.

With this commit the ARM EABI is the only supported supported ABI by
FreeBSD on ARMa 32-bit processors.

X-MFC after: never
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D876

Add the fp{get,set}{mask,round} functions to the public symbols in the map.
These are only exported for armv6hf as the soft-float ABIs have these in
the softfloat Symbol.map file.

In ARM asm code, ensure that every ENTRY(foo) has a matching END(foo).
The EABI unwind info requires a .fnend for every .fnstart, and newer
binutils will complain about seeing two .fnstart in a row. This change
allows newer tools to compile our code.

Reported by: bapt
Reviewed by: imp

From https://sourceware.org/ml/newlib/2014/msg00113.html
By Richard Earnshaw at ARM
>
>GCC has for a number of years provides a set of pre-defined macros for
>use with determining the ISA and features of the target during
>pre-processing. However, the design was always somewhat cumbersome in
>that each new architecture revision created a new define and then
>removed the previous one. This meant that it was necessary to keep
>updating the support code simply to recognise a new architecture being
>added.
>
>The ACLE specification (ARM C Language Extentions)
>(http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.set.swdev/index.html)
>provides a much more suitable interface and GCC has supported this
>since gcc-4.8.
>
>This patch makes use of the ACLE pre-defines to map to the internal
>feature definitions. To support older versions of GCC a compatibility
>header is provided that maps the traditional pre-defines onto the new
>ACLE ones.

Stop using __FreeBSD_ARCH_armv6__ and switch to __ARM_ARCH >= 6 in the
couple of places in tree. clang already implements ACLE. Add a define
that says we implement version 1.1, even though the implementation
isn't quite complete.

Add dl_unwind_find_exidx() for ARM EABI, required for C++ exception
handling. For statically linked apps this uses the __exidx_start/end
symbols set up by the linker. For dynamically linked apps it finds the
shared object that contains the given address and returns the location and
size of the exidx section in that shared object.

The dl_unwind_find_exidx() name is used by other BSD projects and Android,
and is mentioned in clang 3.5 comments as "the BSD interface" for finding
exidx data. GCC (in libgcc_s) expects the exact same API and functionality
to be provided by a function named __gnu_Unwind_Find_exidx(), so we provide
that with an alias ("strong reference").

Reviewed by: kib@
MFC after: 1 week

Set the new floating point exception mask correctly

Submitted by: Keith White <kwhite@site.uottawa.ca>

Rename the fp{get,set}* files so they no longer conflict with the softfloat
version of these files. Keep them within this directory so they can be used
to implement the armv6 version of these functions.

Add the deprecated fp{get,set}* functions, a few ports use them.

Convert from WITHOUT_SYSCALL_COMPAT to MK_SYSCALL_COMPAT.

Add a new ARM TARGET_ARCH, armv6hf. This is considered experimental.

This targets the existing ARMv6 and ARMv7 SoCs that contain a VFP unit.
This is an optional coprocessors may not be present in all devices, however
it appears to be in all current SoCs we support.

armv6hf targets the VFP variant of the ARM EABI and our copy of gcc is too
old to support this. Because of this there are a number of WITH/WITHOUT
options that are unsupported and must be left as the default value. The
options and their required value are:
* WITH_ARM_EABI
* WITHOUT_GCC
* WITHOUT_GNUCXX

In addition, without an external toolchain, the following need to be left
as their default:
* WITH_CLANG
* WITH_CLANG_IS_CC

As there is a different method of passing float and double values to
functions the ABI is incompatible with existing armv6 binaries. To use
this a full rebuild of world is required. Because no floating point values
are passed into the kernel an armv6 kernel with VFP enabled will work with
an armv6hf userland and vice versa.

Implement __flt_rounds for ARMv6 hard-float. The fpscr register stores the
current rounding mode used by the VFP unit.

Remove an extra 1 in an #if line

Reported by: ian@

Fix the spelling of function.

Reported by: ian@

Add an optimised version of the float and double helper functions. These
are only used on armv6 when the vfp unit is detected. They will also be
available for the upcoming armv6hf platform, however while not used by
default there will need to be defined for any software that calls them
directly.

Export _libc_arm_fpu_present as a private symbol to be used by other
system libraries, for example libm.

Replace use of ${.CURDIR} by ${LIBC_SRCTOP} and define ${LIBC_SRCTOP}
if not already defined. This allows building libc from outside of
lib/libc using a reach-over makefile.

A typical use-case is to build a standard ILP32 version and a COMPAT32
version in a single iteration by building the COMPAT32 version using a
reach-over makefile.

Obtained from: Juniper Networks, Inc.

On ARM EABI double precision floating point values are stored in the
endian the CPU is in, i.e. little-endian on most ARM cores.

This allows ARMv4 and ARMv5 boards to boot with the ARM EABI.

Teach siglongjmp about the VFP version of the setjmp buffer.

This fixes a bug where a call to sigsetjmp followed by siglongjmp may fail
when run on a machine with VFP enabled.

Finish pulling in the NetBSD setjmp/longjmp updates on ARM.

Store/restore the VFP registers in setjmp/longjmp on ARM EABI if VFP is
enabled in the kernel. It checks the hw.floatingpoint sysctl to see if
floating-point is available and uses this to determine if it should store
them. If it does it uses a different magic value so longjmp is able to know
if it should load them.

Include machine/setjmp.h to get the definition of _JB_MAGIC__SETJMP. This
allows us to remove it from the ARM copy of machine/asm.h.

Remove part of the NetBSD longjmp code that was not ready to be merged.

Start to merge the updated ARM NetBSD setjump/longjmp functions. To begin
with merge the functions but leave out the code to save/load the VFP
registers as that requires other changes to ensure the VFP is enabled
first.

This removes storing the old fpa registers. These were never fully
supported, and the only user of this code I can find have moved to newer
CPUs which use a VFP.

The getcontext() from the __fillcontextx() call in the
check_deferred_signal() returns twice, since handle_signal() emulates
the return from the normal signal handler by sigreturn(2)ing the
passed context. Second return is performed on the destroyed stack
frame, because __fillcontextx() has already returned. This causes
undefined and bad behaviour, usually the victim thread gets SIGSEGV.

Avoid nested frame and the need to return from it by doing direct call
to getcontext() in the check_deferred_signal() and using a new private
libc helper __fillcontextx2() to complement the context with the
extended CPU state if the deferred signal is still present.

The __fillcontextx() is now unused, but is kept to allow older
libthr.so to be used with the new libc.

Mark __fillcontextx() as returning twice [1].

Reported by: pgj
Pointy hat to: kib
Discussed with: dim
Tested by: pgj, dim
Suggested by: jilles [1]
MFC after: 1 week

When clang builds libc it may insert calls to __aeabi_* functions. Normally
this is not a problem as they are resolved by libgcc. The exception is for
the __aeabi_mem* functions. These call back into libc to the appropriate
function. This causes issues for static binaries as we only link against
libc once so there is no way for it to call into libgcc and back.

The fix for this is to include these symbols in libc but keep them hidden
so binaries use the libgcc version.

Rework the __vdso_* symbols attributes to only make the symbols weak,
but use normal references instead of weak. This makes the statically
linked binaries to use fast gettimeofday(2) by forcing the linker to
resolve references and providing the neccessary functions.

Reported by: bde
Tested by: marius (sparc64)
MFC after: 2 weeks

Add the required __aeabi_* functions to libc.

The floating point functions are here rather than compiler-rt because the
libc softfloat code allows us to set the rounding mode.

Use the compiler-rt version __{u,}divsi3 and __{u,}modsi3 on ARM EABI

Update the syscall calling convention for ARM EABI. We store the syscall
in r7 and use ip to store the old version of r7 as it is not guaranteed to
be kept when calling a subroutine. The kernel will preserve the register
across system calls.

Silence a clang warning by telling it we are only interested in left
shifting the lower 32bits of the floating point value when we demangle it.

Merging of projects/armv6, part 2

Handle TLS for ARMv6 and ARMv7

Per kib, since __flt_rounds is being added to FreeBSD 10, it
belongs in FBSD_1.3.

MFC after: 1 week

__flt_rounds is a public symbol (expands from the FLT_ROUNDS macro),
so include it in the public namespace on arm just as with
other architectures.

This corrects r236816.

Submitted by: Jan Sieka
MFC after: 1 week

__flt_rounds was omitted from the exported symbols here.

Submitted by: Jan Sieka
Reviewed by: arm@
MFC after: 1 week

Replace the C implementation of __aeabi_read_tp with an assembly version.
This ensures we follow the ABI by preserving registers r1-r3.

Reviewed by: jmallett, imp

Unlike other functions __aeabi_read_tp function must preserve r1-r3. The
currently generated code clobbers r3. Fix this by loading ARM_TP_ADDRESS
using inline assembly.

Approved by: imp (mentor)

- Revert part of r234005, which I did not intend to commit.
Sorry! :(

- Add kernel config file for QEMU-emulated gumstix board.

Unbreak trhe build by including proper header

Fix TLS for statically linked binaries

Approved by: cognet

Add __aeabi_read_tp to the symbol list.

Add __aeabi_read_tp function required for thread-local storage

Reviewed by: cognet

Make the sys/ucontext.h self-contained by changing the return type
of __getcontextx_size(3) from size_t to int.

PR: ports/164654
MFC after: 1 month

Add API for obtaining extended machine context states that cannot be
fit into existing mcontext_t.

On i386 and amd64 do return the extended FPU states using
getcontextx(3). For other architectures, getcontextx(3) returns the
same information as getcontext(2).

Tested by: pho
MFC after: 1 month

Don't inline fenv.h functions on arm for now. Inlining makes sense:
the function bodies require only 2 to 10 instructions. However, it
leads to application binaries that refer to a private ABI, namely, the
softfloat innards in libc. This could complicate future changes in
the implementation of the floating-point emulation layer, so it seems
best to have programs refer to the official fe* entry points in libm.

Implement FLT_ROUNDS for arm. Some (all?) arm FPUs lack support for
dynamic rounding modes, but FPUless chips that use softfloat can support it
because everything is emulated anyway. (We presently have incomplete
support for hardware FPUs.)

Submitted by: Ian Lepore

Convert softfloat to use the standard exception flag and rounding macros
in fenv.h instead of the non-standard and incomplete ones in ieeefp.h.

Thanks to Ian Lepore for testing this patch.

Correct some bugs that resulted from arm/_fpmath.h being blindly copied
from the x86 version, which has a completely different long double
format.

Submitted by: Maks Verver

Merge index() and strchr() together.

As I looked through the C library, I noticed the FreeBSD MIPS port has a
hand-written version of index(). This is nice, if it weren't for the
fact that most applications call strchr() instead.

Also, on the other architectures index() and strchr() are identical,
meaning we have two identical pieces of code in the C library and
statically linked applications.

Solve this by naming the actual file strchr.[cS] and let it use
__strong_reference()/STRONG_ALIAS() to provide the index() routine. Do
the same for rindex()/strrchr().

This seems to make the C libraries and static binaries slightly smaller,
but this reduction in size seems negligible.

Replace a proliferation of buggy MD implementations of modf() with a
working MI one. The MI one only needs to be overridden on machines
with non-IEEE754 arithmetic. (The last supported one was the VAX.)
It can also be overridden if someone comes up with a faster one that
actually passes the regression tests -- but this is harder than it sounds.

Fix typos - remove duplicate "the".

PR: bin/154928
Submitted by: Eitan Adler <lists at eitanadler.com>
MFC after: 3 days

The NetBSD Foundation has granted permission to remove clause 3 and 4 from
their software.

Obtained from: NetBSD

Remove unneeded stdlib directories.

It's not necessary to add stdlib directories for each architecture, even
if the architecture doesn't implement any files of its own.

Submitted by: Christoph Mallon

- Eliminate extra subcs instruction. I have not noticed before that we
always perform substraction now, so no instruction could be rordered
to eliminate the conditional substraction.

- Fix strncmp on arm. Return 0 as result without performing the
main cycle only if the len passed is equal to 0. If end address
overflows use last possible address as the end address.

Based on: discussion on arm@
MFC after: 1 month

Use GCC's __SOFTFP__ to test whether we're being compiled
with softfloat or not. Now -msoft-float can be overridden
more easily.

revert r191633; this breaks at91 & xscale (likely all arm)

Change the test at the beginning of strncmp(), from being if (len - 1) < 0
to if (len == 0).
The length is supposed to be unsigned, so len - 1 < 0 won't happen except
if len == 0 anyway, and it would return 0 when it shouldn't, if len was
> INT_MAX.

Spotted out by: Channa <channa kad gmail com>

These warnings are only relevant on NetBSD it seems. They don't seem
to be relevant to FreeBSD at all.

Add support for the FPA floating-point format on ARM. The
FPA floating-point format is identical to the VFP format,
but is always stored in big-endian.
Introduce _IEEE_WORD_ORDER to describe the byte-order of
the FP representation.

Obtained from: Juniper Networks, Inc

Mark uname(), getdomainname() and setdomainname() with COMPAT_FREEBSD4.

Looking at our source code history, it seems the uname(),
getdomainname() and setdomainname() system calls got deprecated
somewhere after FreeBSD 1.1, but they have never been phased out
properly. Because we don't have a COMPAT_FREEBSD1, just use
COMPAT_FREEBSD4.

Also fix the Linuxolator to build without the setdomainname() routine by
just making it call userland_sysctl on kern.domainname. Also replace the
setdomainname()'s implementation to use this approach, because we're
duplicating code with sysctl_domainname().

I wasn't able to keep these three routines working in our
COMPAT_FREEBSD32, because that would require yet another keyword for
syscalls.master (COMPAT4+NOPROTO). Because this routine is probably
unused already, this won't be a problem in practice. If it turns out to
be a problem, we'll just restore this functionality.

Reviewed by: rdivacky, kib

Let libstand(3) build on ARM.

This is a pre-requisite for loader(8) + U-Boot support library on this arch.

Arrange so that the NaN returned by strtod("nan", NULL) is the same as
the NaN returned by strtod("nan()", NULL).

Unbreak arm build by removing duplicate symbols.

MFKernel: do not use __XSCALE__ to detect if clz/pld/ldrd/strd are
available, use _ARM_ARCH_5/_ARM_ARCH_5E instead.

MFC After: 3 days

Fix remaining syntax errors (missing semicolons)

Submitted by: Björn König <bkoenig@cs.tu-berlin.de>
Approved by: re (kensmith, followup commits)

Add missing \ characters in PSEUDO() macro on arm. Oops.

Submitted by: cognet
Approved by: re (kensmith)

Classify mmap, lseek, pread, pwrite, truncate, ftruncate as pseudo
syscalls, unless WITHOUT_SYSCALL_COMPAT is defined. The default case
will have the .c wrappers still. If you define WITHOUT_SYSCALL_COMPAT,
the .c wrappers will go away and libc will make direct syscalls.

After 7-stable starts, the direct syscall method will be default.

Approved by: re (kensmith)

Adjust the syscall stub macros to be consistent in their meaning. In
particular:
SYSCALL() makes a syscall, with errno handling, and continues execution
directly after the macro in the non-error case.
RSYSCALL() is just like SYSCALL(), but returns after success.
Both SYSCALL(name) and RSYSCALL(name) export "__sys_name" as a strong
symbol, with "_name" and "name" as weak aliases.
PSEUDO() is just like RSYSCALL(), but skipping the "name" weak alias. It
still does "__sys_name" and "_name".

Change i386 to add errno handling to PSEUDO. The same for amd64 and
sparc64, with appear to have copied the behavior.
ia64 was correct (as was alpha). Just remove some apparently unused
variants of the macros. (untested!)
I believe powerpc is correct.
Fix arm to not export "name" from the PSEUDO case. Remove apparently
extra unused variants. (untested!)

The errno problem manifested on i386/amd64/sparc64 by having "PSEUDO"
classified syscalls return without setting errno. eg: "addr = mmap()"
could return with "addr" = 22 instead of setting errno to 22 and
returning -1.

Approved by: re (kensmith)

Fix sbrk.S to use _end symbol the same way brk.s was fixed some time
ago. sbrk.S should have gotten the same change then but was forgotten.

Approved by: re (bmah)
PR: kern/114049

Some libc symbol map cleanups.

net: endhostdnsent is named _endhostdnsent and is
private to netdb family of functions.

posix1e: acl_size.c has been never compiled in,
so there's no "acl_size".

rpc: "getnetid" is a static function.

stdtime: "gtime" is #ifdef'ed out in the source.

some symbols are specific only to some architectures,
e.g., ___tls_get_addr is only defined on i386.

__htonl, __htons, __ntohl and __ntohs are no longer
functions, they are now (internal) defines in
<machine/endian.h>.

Submitted by: ru

Use __mcount() instead of _mcount() to reduce diffs with NetBSD.

Use built-in _end symbol insteadof 'end' for consistency with other
architectures. Linker defines end is synonym for _end.

Do not declare float_detect_tininess as external if it will be re-delared
as static later.

Do not export 'end' symbol. It is not meant to be visible to outside
world and it wreak havoc if libc collides with other versioned
libraries.

Remove .mcount from gmon's Symbol map and add it to the appropriate
arch. It can be named differently depending on the arch (.mcount,
_mcount).

Submitted by: marius

Use C comments since we now preprocess these files with CPP.

The distinction between quiet and signaling NaN formats is
machine-dependent; these files tell the latest version of gdtoa
what to do.

Cleanup: we always have to use __error() now, and we shouldn't provide a
errno symbol, so completely remove the !_REENTRANT case.

Spotted out by: ru

Remove a forgotten file.

Instead of re-implementing hton[ls] and friends for each arch, add a new MI
file, net/ntoh.c, which just implement them using the inline functions from
<sys/endian.h>.

Suggested by: bde

Provide definitions suitable for arm big-endian.

If __ARMEB__ is defined, we're already using the network byte order, so
there's no need to to anything in the hton* functions, beside returning
the parameter.

Spotted out by: Oleksandr Tymoshenko <gonzo@freebsd.org>

GC old a.out and K&R support.

Add each directory's symbol map file to SYM_MAPS.

Add symbol maps and initial symbol version definitions to libc.

Reviewed by: davidxu

Fix a long line in copyright notice.

Pointed out by: Gavin Atkinson gavin.atkinson ury york ac uk

Add an asm version of strlen() for arm (how useful).

Use the correct values for softfloat, in both the little endian and the big
endian cases.

Define LDBL_NBIT to be a mask indicating the position of the integer
bit in a long double. For architectures that don't have such a bit,
LDBL_NBIT is 0. This makes it possible to say `mantissa & ~LDBL_NBIT'
in places that previously used an #ifdef to select the right expression.
The optimizer should dispense with the extra arithmetic when LDBL_NBIT
is 0.

Update my email address.

Replace the ldexp() implementation in libc with a renamed copy of the
scalbn() implementation from libm. (The two functions are defined to
be identical, but ldexp() lives in libc for backwards compatibility.)
The old ldexp() implementation...
- was more complicated than this one
- set errno instead of raising FP exceptions
- got some corner cases wrong
(e.g. ldexp(1.0, 2000) in round-to-zero mode)

The new implementation lives in libc/gen instead of
libc/$MACHINE_ARCH/gen, since we don't need N copies of a
machine-independent file. The amd64 and i386 platforms
retain their fast and correct MD implementations and
override this one.

Eliminate gdtoa.mk and move its contents to ${MACHINE_ARCH}/Makefile.inc.
The purpose of having a separate file involved an abandoned scheme that
would have kept contrib/gdtoa out of the include path for the rest of libc.

Use the RET macro.
For setjmp() and longjmp(), put the signal mask where it's supposed to be,
instead of in the space reserved for fp regs.

Add a week alias __siglongjmp => siglongjmp.

MFKernel: Implement ffs with clz on Xscale.

Don't define SOFTFLOAT directly in source files, it's now done in the Makefile.

Fix signalcontext and makecontext.

Remove getcontext.S, it is not needed.

Import a Makefile for arm.

Make setjmp()/longjmp() use sigprocmask.

Add a dummy set_tp().

Always use bx for returning on Xscale.

Obtained from: NetBSD

Fix the align-to-32-bits code.

Obtained from: NetBSD

Replace seven nominally MD implementations of frexp() that are broken
for subnormals with one implementation that works.

Implement the classification macros isfinite(), isinf(), isnan(), and
isnormal() the hard way, rather than relying on fpclassify(). This is
a lose in the sense that we need a total of 12 functions, but it is
necessary for binary compatibility because we have never bumped libm's
major version number. In particular, isinf(), isnan(), and isnanf()
were BSD libc functions before they were C99 macros, so we can't
reimplement them in terms of fpclassify() without adding a dependency
on libc.so.5. I have tried to arrange things so that programs that
could be compiled in FreeBSD 4.X will generate the same external
references when compiled in 5.X. At the same time, the new macros
should remain C99-compliant.

The isinf() and isnan() functions remain in libc for historical
reasons; however, I have moved the functions that implement the macros
isfinite() and isnormal() to libm where they belong. Moreover,
half a dozen MD versions of isinf() and isnan() have been replaced
with MI versions that work equally well.

Prodded by: kris

Import the FreeBSD/arm libc bits.

Obtained from: NetBSD