avoid array-bounds issues by using more complete types.

also, don't cast to a type that includes an extra, unused, member.

while here, replace the hard coded offsets in setjmp.S and some
asserts in longjmp.c with assym.h and shared structures for all
the movings parts, and asserts based upon those structures.

avoids GCC 12 warnings.

Include sparc_v8 library into sparc64 32-bit compat libc library.

branches: 1.22.12; 1.22.22;
Rename ${SRCS.{alpha,arm,...}.gen} to ${LSRCS.{alpha,arm,...}.gen} because
they ended up in ${LSRCS}, not ${SRCS}. ${SRCS.*} namespace will be used
for more useful things. No functional changes intended.

build frexp_ieee754 and ldexp_ieee754 in the "compat" subtree
(There is an assembler version of modf which needs to be checked.)

Switch sparc to the new compat code layout.

Push back the descriptions of NaN formats, and descriptions of the
distinction between signalling NaNs and quiet NaNs back into the
machine-dependent headers; treat the implementation of __nanf in the
same spirit.

IEEE 754 leaves the distinction between signalling NaNs and quiet NANs
to the implementation, and unlike our headers used to suggest they're
not identical in the interpretation of the fraction's MSb; in due
course, make those of hppa, mips, sh3, and sh5 reflect reality.

branches: 1.18.6;
Use setcontext() instead of sigreturn() to implement longjmp().

* Turn isinf(3) and isnan(3) into C99-style macros.
* Make it possible for ports to override these (i.e., VAX).
* Remove isnanl(), which was internal to libc only.

Forgot to build signbit() library parts in previous; noticed by mrg.

Add C99 fpclassify(), isfinite(), isnormal(), and signbit() macros.

Add __infinityf and __infinityl, float respectively long double analogs
of __infinity.

* Since there is no single portable IEEE 754 format for a long double,
keep a common implementation of isinfl() and isnanl() to be used by
platforms where `long double' == `double'; move others into
machine-dependent code.
* In due course, consider __VFP_FP__ on arm.

Rework how dependency generation is performed:

* DPSRCS contains extra dependencies, but is _NOT_ added to CLEANFILES.
This is a change of behaviour. If a Makefile wants the clean semantics
it must specifically append to CLEANFILES.
Resolves PR toolchain/5204.

* To recap: .d (depend) files are generated for all files in SRCS and DPSRCS
that have a suffix of: .c .m .s .S .C .cc .cpp .cxx

* If YHEADER is set, automatically add the .y->.h to DPSRCS & CLEANFILES

* Ensure that ${OBJS} ${POBJS} ${LOBJS} ${SOBJS} *.d depend upon ${DPSRCS}

* Deprecate the (short lived) DEPENDSRCS


Update the various Makefiles to these new semantics; generally either
adding to CLEANFILES (because DPSRCS doesn't do that anymore), or replacing
specific .o dependencies with DPSRCS entries.

Tested with "make -j 8 distribution" and "make distribution".

Build _isinfl() and _isnanl().

Rename ieee754_function.c to function_ieee754.c, following the convention
used in exec_format.c, loadfile_format.c, subsys_machdep.c etc.
Per discussion with Christos.

Add swapcontext() lint stub.

Merge the nathanw_sa branch.

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

branches: 1.6.6;
C99: Define a NAN macro in <math.h> which evaulates to a constant expression of
a single-precision quiet NaN; only to be defined on platforms that do support
this value.

Move the bswap functions from libutil to libc (this bups the
minor of libc and the major of libutil). For little-endian architectures
merge the bnswap() assembly versions with nto* and hton* using symbols
aliasing. Use symbol renaming for the bswap function in this case to avoid
namespace pollution.
Declare bswap* in machine/bswap.h, not machine/endian.h. For little-endian
machines, common code for inline macros go in machine/byte_swap.h
Sync libkern with libc.
Adjust #include in kernel sources for machine/bswap.h.

Make the sparc work again; some work from jason, some from me.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

don't forget inifinity.c

need these for new gen/Makefile

Switch sparc to the new compat code layout.

Add missing <compat/include/setjmp.h>

The sc_g1, sc_o0 members in the jmp_buf aren't used.

Use setcontext() instead of sigreturn() to implement longjmp().

Switch sparc to the new compat code layout.

Since libpthread may want to interpose signal handling, we can't directly
invoke the sigprocmask syscall trap. So build a stack frame and call
the signal handling functions by name.

Use setcontext() instead of sigreturn() to implement longjmp().

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

Make the sparc work again; some work from jason, some from me.

Switch sparc to the new compat code layout.

Fix the non pic version too.

PR/6285: Tom Ivar Helbekkmo: sigsetjmp/siglongjmp broken after current signal
changes.

Make the sparc work again; some work from jason, some from me.

sparc _lwp_makecontext, makecontext: Sort includes.

No functional change intended.

Tidying up for:

PR kern/59327: user stack pointer is not aligned properly

include <sys/param.h> for STACK_ALIGNBYTES

sparc: Use STACK_ALIGNBYTES macro when aligning stack pointer.

Prompted by:

PR kern/59327: user stack pointer is not aligned properly

branches: 1.7.44;
void cast

branches: 1.6.4;
Allow storing and receiving the LWP private pointer via ucontext_t
on all platforms except VAX and IA64. Add fast access via register for
AMD64, i386 and SH3 ports. Use this fast access in libpthread to replace
the stack based pthread_self(). Implement skeleton support for Alpha,
HPPA, PowerPC, SPARC and SPARC64, but leave it disabled.

Ports that support this feature provide __HAVE____LWP_GETPRIVATE_FAST in
machine/types.h and a corresponding __lwp_getprivate_fast in
machine/mcontext.h.

This material is based upon work partially supported by
The NetBSD Foundation under a contract with Joerg Sonnenberger.

branches: 1.5.8; 1.5.20;
Remove clause 3 and 4 from TNF licenses

branches: 1.4.18;
Add missing __RCSID()

Make sure we reference getcontext() by its internal name.

Merge the nathanw_sa branch.

branches: 1.1.2;
file _lwp.c was initially added on branch nathanw_sa.

Use save instruction to set up a local stack frame.

This fixes a segmentation fault caused by bash 4.3 on sparc64
kernels with 32-bit userland, bash uses _setjmp/_longjmp heavyly
via sigsetjmp/siglongjmp since 4.3.

For 32-bit compat library which is compiled with -mcpu=ultrasparc
option (and define __sparc_v9__), use a similar code to 64-bit
library.

branches: 1.9.6; 1.9.10; 1.9.12; 1.9.18; 1.9.20;
Save a few global registers during set/longjmp - at least the application
registers and the only currently used system register (%g7).
Sparc now passes the setjmp tests (and should be able to build perl again).

branches: 1.8.8;
Remove clause 3 and 4 from TNF licenses

branches: 1.7.30;
Fix comment: g6 => o1

A new implementation of _setjmp/_longjmp that uses the T_FLUSHWIN trap.
This means the stack frame and program counter can restored directly
from the jmp_buf, eliminating the need to backtrack through frames
which does not work in all cases.

Change immediate label references to _C_LABEL().

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

Avoid load/store doubles; jmp_buf is long aligned (Michael Eriksson; PR#2180)

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

Avoid using %g7

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

rcsid police

update for removed DEFS.h.

Preserve the equality "x == y*(x/y)+(x%y)" for negative y; from Lon Willett.

make an arch directory in libc, and move all machine dirs into it

On ports without __HAVE_LONG_DOUBLE, make fabsl alias fabs.

For some reason, fabs lives in libc, not in libm, and our tests now
detect when fabs or fabsl is missing from libm. For those ports that
sometimes have long double and sometimes don't, make it conditional.

Still missing: fabs _and_ fabsl on ia64. Need help from an itanium
wizard! Other portmasters: Please take a look and see if I missed
any ports that might have long double where this alias will not work.

branches: 1.4.96; 1.4.98;
Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

Pass PICFLAGS down to cc-as-as and use __PIC__ to decide if it is small
vs big PIC mode. Retire -DPIC and -DBIGPIC.

branches: 1.5.56; 1.5.62;
Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

Make PIC-safe.

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

c89 prototypes, unsigned int

branches: 1.6.44;
__asm__ -> __asm

Add missing __RCSID()

Corrent map order to match sparc/ieeefp.h.

RCS Id Police.

Pull in __flt_rounds() prototype.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

c89 prototypes, unsigned int

branches: 1.5.44;
__asm__ -> __asm

Add missing __RCSID()

Add internal names for fp{get,set}{mask,round,sticky}(), and
externally-visible weak aliases for the internal names.

branches: 1.2.12;
RCS Id Police.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

c89 prototypes, unsigned int

branches: 1.5.44;
__asm__ -> __asm

Add missing __RCSID()

Add internal names for fp{get,set}{mask,round,sticky}(), and
externally-visible weak aliases for the internal names.

branches: 1.2.12;
RCS Id Police.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

c89 prototypes, unsigned int

branches: 1.5.44;
__asm__ -> __asm

Add missing __RCSID()

Add internal names for fp{get,set}{mask,round,sticky}(), and
externally-visible weak aliases for the internal names.

branches: 1.2.12;
RCS Id Police.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

c89 prototypes, unsigned int

branches: 1.5.44;
__asm__ -> __asm

Add missing __RCSID()

Add internal names for fp{get,set}{mask,round,sticky}(), and
externally-visible weak aliases for the internal names.

branches: 1.2.12;
RCS Id Police.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

sparc/fpsetround: fix the nearby signed integer overflow as well

Same as for sparc64 a few days ago.

fix lint

c89 prototypes, unsigned int

branches: 1.5.44;
__asm__ -> __asm

Add missing __RCSID()

Add internal names for fp{get,set}{mask,round,sticky}(), and
externally-visible weak aliases for the internal names.

branches: 1.2.12;
RCS Id Police.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

convert to full ANSI C.

branches: 1.5.44; 1.5.50;
__asm__ -> __asm

Add missing __RCSID()

Add internal names for fp{get,set}{mask,round,sticky}(), and
externally-visible weak aliases for the internal names.

branches: 1.2.12;
RCS Id Police.

Added __flt_rounds, fp{get,set}{mask,round,sticky}.

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

branches: 1.4.10;
Trivial KNF.

Just some minor cleanup.

Add missing math.h include
Fix RCSID's

make an arch directory in libc, and move all machine dirs into it

Move getcontext.S from gen to sys, where it belongs.

Merge the nathanw_sa branch.

branches: 1.1.2;
file getcontext.S was initially added on branch nathanw_sa.

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

branches: 1.5.2;
check LIBC_SCCS

delint

const poisoning.

Fix RCSID's

First cut; not sure if it's right. Very like it is, because it's
the same as the m68k versions..

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

branches: 1.7.6;
Delint.

Separate isnan() into a separate module, and make isinf()/isnan() use ieee.h.

delint

Need internal names for isinf() and isnan().

Add missing math.h include.
Fix RCSID's

Add explicit return type

branches: 1.1.4;
make an arch directory in libc, and move all machine dirs into it

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

branches: 1.6.6;
Delint.

Separate isnan() into a separate module, and make isinf()/isnan() use ieee.h.

Need internal names for isinf() and isnan().

Add missing math.h include
Fix RCSID's

Add explicit return type

branches: 1.1.4;
make an arch directory in libc, and move all machine dirs into it

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

Rename a parameter to fix build problem with new toolchain.

branches: 1.9.10;
Another microoptimization. Take advantage of the addition already having set
the flags for the <=0 comparison.

Reuse the trick of loading 0.0 (rather than 1.0) and then modifying the
exponent. It's a bit faster on some machines.

Remove more unused mulexp variables.

ldexp(denormal, exp>1023) would generate the wrong result in all non-overflow
cases. Totally rework this code to fix this bug *and* make it faster.

Don't ever return -0.0.

Minor style change.

Just some minor cleanup.

Add missing math.h include
Fix RCSID's

make an arch directory in libc, and move all machine dirs into it

sparc, sparc64 longjmp: Use _UC_SIGMASK to restore signal mask.

This way, restoring the signal mask and restoring the stack pointer
happen atomically with respect to signal handler calls, whereas using
sigprocmask would restore the signal mask _before_ the stack pointer,
breaking sigaltstack.

The motivation for using sigprocmask first and then setcontext later,
rather than _UC_SIGMASK in setcontext, was to get SA-based libpthead
sigprocmask interposition. But that's long gone and unlikely to come
back.

PR lib/57946: longjmp fails to restore stack first before restoring
signal mask on most architectures

branches: 1.5.2;
fix typo in comment

avoid array-bounds issues by using more complete types.

also, don't cast to a type that includes an extra, unused, member.

while here, replace the hard coded offsets in setjmp.S and some
asserts in longjmp.c with assym.h and shared structures for all
the movings parts, and asserts based upon those structures.

avoids GCC 12 warnings.

Save a few global registers during set/longjmp - at least the application
registers and the only currently used system register (%g7).
Sparc now passes the setjmp tests (and should be able to build perl again).

branches: 1.2.8;
Remove clause 3 and 4 from TNF licenses

branches: 1.1.18;
Switch sparc to the new compat code layout.

sparc _lwp_makecontext, makecontext: Sort includes.

No functional change intended.

Tidying up for:

PR kern/59327: user stack pointer is not aligned properly

include <sys/param.h> for STACK_ALIGNBYTES

sparc: Use STACK_ALIGNBYTES macro when aligning stack pointer.

Prompted by:

PR kern/59327: user stack pointer is not aligned properly

branches: 1.3.8; 1.3.76;
Remove clause 3 and 4 from TNF licenses

branches: 1.2.30;
Merge the nathanw_sa branch.

branches: 1.1.2;
file makecontext.c was initially added on branch nathanw_sa.

Pass PICFLAGS down to cc-as-as and use __PIC__ to decide if it is small
vs big PIC mode. Retire -DPIC and -DBIGPIC.

branches: 1.6.56; 1.6.62;
Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

Insert some Position Independent Code.

Use %hi operator when fiddling a bit high...

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

Use reach-over sources from common/lib/libc

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

Make NAN a compile time constant (with help from the compiler). Suggested
by krister. Fixes PR 40695.
Make references to the old construct (which we can't remove for binary
compatibility reasons) emit a linker warning.

branches: 1.3.2; 1.3.32;
Push back the descriptions of NaN formats, and descriptions of the
distinction between signalling NaNs and quiet NaNs back into the
machine-dependent headers; treat the implementation of __nanf in the
same spirit.

IEEE 754 leaves the distinction between signalling NaNs and quiet NANs
to the implementation, and unlike our headers used to suggest they're
not identical in the interpretation of the fraction's MSb; in due
course, make those of hppa, mips, sh3, and sh5 reflect reality.

Clean up some rampant code duplication wrt ieee number handling:
- Add alignment-safe double and float unions.
- Use the above for the __infinity and __nan constants on all
architectures that use the standard ieee754 representation of
those constants.
- Add a single copy of various ieee754 math functions (frexp, isinf,
isnan, ldexp and modf) that had numerous duplicates among the
arch-specific directories.
- Use the above functions on all architectures where the generic C
versions where used. Architectures that had local assembly
routines are untouched (for those functions only).

branches: 1.1.6;
C99: Define a NAN macro in <math.h> which evaulates to a constant expression of
a single-precision quiet NaN; only to be defined on platforms that do support
this value.

Mark _resumecontext as dead. ANSIfy all declarations for it.

branches: 1.4.8;
Remove clause 3 and 4 from TNF licenses

branches: 1.3.10;
Sync all resumecontext.c versions with the changes originally made
by Matthias Drochner to i386 and alpha:

-check for a NULL uc_link before calling setcontext(2); do a real exit(3)
instead with exit handlers and all that
-If setcontext(2) returns (which it shouldn't), do an _exit(-1) rather
than relying on a sensible return value to use as exit code. Makes
it less likely that an ucontext corruption goes unnoticed.

branches: 1.2.16;
Merge the nathanw_sa branch.

branches: 1.1.2;
file resumecontext.c was initially added on branch nathanw_sa.

Use reach-over sources from common/lib/libc

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

Consistently pass 0 as first and ignored argument to sigprocmask in the
setjmp implementations.

NFCI.

avoid array-bounds issues by using more complete types.

also, don't cast to a type that includes an extra, unused, member.

while here, replace the hard coded offsets in setjmp.S and some
asserts in longjmp.c with assym.h and shared structures for all
the movings parts, and asserts based upon those structures.

avoids GCC 12 warnings.

Save a few global registers during set/longjmp - at least the application
registers and the only currently used system register (%g7).
Sparc now passes the setjmp tests (and should be able to build perl again).

In handwritten asm use -fPIC code instead of -fpic, our libc has grown
large enough for GOT to be larger than 8k.

While here kill redundant PIC ifdefs in setjmp.S - sparc "call"
instruction is piccy by itself.

Tested by martin@

branches: 1.10.4;
Use CCFSZ instead of 96 for standard save operations.

branches: 1.9.4;
Switch sparc to the new compat code layout.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

Make the sparc work again; some work from jason, some from me.

Change immediate label references to _C_LABEL().

Quick fix to repair runtime link problem with libc - "SYS_sigaltstack
undefined". The sigaltstack structure layout didn't actually change on
the sparc, so just change the syscall name. A better fix would probably
be to replace the direct system call with a function call to the libc
sigaltstack().

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

sigaltstack

Use sigstack() in stead of sigaltstack() until we have a sigaltstack()
in the kernel.

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it

Pass PICFLAGS down to cc-as-as and use __PIC__ to decide if it is small
vs big PIC mode. Retire -DPIC and -DBIGPIC.

branches: 1.6.30; 1.6.36;
In handwritten asm use -fPIC code instead of -fpic, our libc has grown
large enough for GOT to be larger than 8k.

While here kill redundant PIC ifdefs in setjmp.S - sparc "call"
instruction is piccy by itself.

Tested by martin@

branches: 1.5.10;
Switch sparc to the new compat code layout.

Make the sparc work again; some work from jason, some from me.

Change immediate label references to _C_LABEL().

Simplify.

Machine dependent sig{set,long}jmp().

avoid array-bounds issues by using more complete types.

also, don't cast to a type that includes an extra, unused, member.

while here, replace the hard coded offsets in setjmp.S and some
asserts in longjmp.c with assym.h and shared structures for all
the movings parts, and asserts based upon those structures.

avoids GCC 12 warnings.

Pass PICFLAGS down to cc-as-as and use __PIC__ to decide if it is small
vs big PIC mode. Retire -DPIC and -DBIGPIC.

branches: 1.4.2;
setcontext() used to be incompatible with -lpthread since it affected
the TLS pointer, therefore wrecking the pthread environement.

Some ports had _UC_TLSBASE flag or equivalent (_UC_UNIQUE on alpha)
that controlled whether setcontext() would change the TLS pointer.
This change let libpthread override setcontext() with its own version
that unsets _UC_TLSBASE, enabling safe usage of setcontext() with
-lpthread.

We also have the following required changes here:
- rename alpha's _UC_UNIQUE into _UC_TLSBASE
- add _UC_TLSBASE definition in header file for all ports
(powerpc, sh3, sparc and sparc64 lack the implementation for now)
- introduce a libc stub that can be overriden for setcontext()
- modify MD libcs swapcontext() implementations so that they use the
setcontext() libc stub instead of doing a plain system call.

While we are there:
- document various MD _UC_* flags in header file
- add libc and libpthread tests for swapcontext() behavior
(hopefully helpful to spot MD problems introduced with this change)

Future work:
- Deciding whether kernel support or _UC_TLSBASE should be added for
powerpc, sh3, sparc and sparc64 is left to portmasters
sparc64

Approved by core@

branches: 1.3.4; 1.3.8;
Remove clause 3 and 4 from TNF licenses

branches: 1.2.30;
Merge the nathanw_sa branch.

branches: 1.1.2;
file swapcontext.S was initially added on branch nathanw_sa.

Use reach-over sources from common/lib/libc

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22280, verified by myself.

RCSID fixes: Always use the NetBSD rcsid and the macro RCSID() defined in
<machine/asm.h>; Also syscalls should be protected using the SYSLIBC_SCCS
define not LIBC_SCCS

Remove DEFS.h, which has been just a placeholder for a long time.

make an arch directory in libc, and move all machine dirs into it

Clean up deleted files.

make an arch directory in libc, and move all machine dirs into it