The previous barrier implementation did not fulfill the POSIX requirements
for when a barrier can be destroyed. Specifically, it was possible that
threads that haven't noticed yet that their round is complete still access
the barrier's memory, and that those accesses can happen after the barrier
has been legally destroyed.
The new algorithm does not have this issue, and it avoids using a lock
internally.
It was noted in
<https://sourceware.org/ml/libc-alpha/2012-09/msg00305.html> that the
bits/*.h naming scheme should only be used for installed headers.
This patch renames bits/atomic.h to atomic-machine.h to follow that
convention.
This is the only change in this series that needs to change the
filename rather than simply removing a directory level (because both
atomic.h and bits/atomic.h exist at present).
Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by the patch).
[BZ #14912]
* sysdeps/aarch64/bits/atomic.h: Move to ...
* sysdeps/aarch64/atomic-machine.h: ...here.
(_AARCH64_BITS_ATOMIC_H): Rename macro to
_AARCH64_ATOMIC_MACHINE_H.
* sysdeps/alpha/bits/atomic.h: Move to ...
* sysdeps/alpha/atomic-machine.h: ...here.
* sysdeps/arm/bits/atomic.h: Move to ...
* sysdeps/arm/atomic-machine.h: ...here. Update comments.
* bits/atomic.h: Move to ...
* sysdeps/generic/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/i386/bits/atomic.h: Move to ...
* sysdeps/i386/atomic-machine.h: ...here.
* sysdeps/ia64/bits/atomic.h: Move to ...
* sysdeps/ia64/atomic-machine.h: ...here.
* sysdeps/m68k/coldfire/bits/atomic.h: Move to ...
* sysdeps/m68k/coldfire/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/m68k/m680x0/m68020/bits/atomic.h: Move to ...
* sysdeps/m68k/m680x0/m68020/atomic-machine.h: ...here.
* sysdeps/microblaze/bits/atomic.h: Move to ...
* sysdeps/microblaze/atomic-machine.h: ...here.
* sysdeps/mips/bits/atomic.h: Move to ...
* sysdeps/mips/atomic-machine.h: ...here.
(_MIPS_BITS_ATOMIC_H): Rename macro to _MIPS_ATOMIC_MACHINE_H.
* sysdeps/powerpc/bits/atomic.h: Move to ...
* sysdeps/powerpc/atomic-machine.h: ...here. Update comments.
* sysdeps/powerpc/powerpc32/bits/atomic.h: Move to ...
* sysdeps/powerpc/powerpc32/atomic-machine.h: ...here. Update
comments. Include <atomic-machine.h> instead of <bits/atomic.h>.
* sysdeps/powerpc/powerpc64/bits/atomic.h: Move to ...
* sysdeps/powerpc/powerpc64/atomic-machine.h: ...here. Include
<atomic-machine.h> instead of <bits/atomic.h>.
* sysdeps/s390/bits/atomic.h: Move to ...
* sysdeps/s390/atomic-machine.h: ...here.
* sysdeps/sparc/sparc32/bits/atomic.h: Move to ...
* sysdeps/sparc/sparc32/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/sparc/sparc32/sparcv9/bits/atomic.h: Move to ...
* sysdeps/sparc/sparc32/sparcv9/atomic-machine.h: ...here.
* sysdeps/sparc/sparc64/bits/atomic.h: Move to ...
* sysdeps/sparc/sparc64/atomic-machine.h: ...here.
* sysdeps/tile/bits/atomic.h: Move to ...
* sysdeps/tile/atomic-machine.h: ...here.
* sysdeps/tile/tilegx/bits/atomic.h: Move to ...
* sysdeps/tile/tilegx/atomic-machine.h: ...here. Include
<sysdeps/tile/atomic-machine.h> instead of
<sysdeps/tile/bits/atomic.h>.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/tile/tilepro/bits/atomic.h: Move to ...
* sysdeps/tile/tilepro/atomic-machine.h: ...here. Include
<sysdeps/tile/atomic-machine.h> instead of
<sysdeps/tile/bits/atomic.h>.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/arm/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/arm/atomic-machine.h: ...here. Include
<sysdeps/arm/atomic-machine.h> instead of
<sysdeps/arm/bits/atomic.h>.
* sysdeps/unix/sysv/linux/hppa/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/hppa/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/m68k/coldfire/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/m68k/coldfire/atomic-machine.h: ...here.
(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/nios2/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/nios2/atomic-machine.h: ...here.
(_NIOS2_BITS_ATOMIC_H): Rename macro to _NIOS2_ATOMIC_MACHINE_H.
* sysdeps/unix/sysv/linux/sh/bits/atomic.h: Move to ...
* sysdeps/unix/sysv/linux/sh/atomic-machine.h: ...here.
* sysdeps/x86_64/bits/atomic.h: Move to ...
* sysdeps/x86_64/atomic-machine.h: ...here.
* include/atomic.h: Include <atomic-machine.h> instead of
<bits/atomic.h>.
This adds new functions for futex operations, starting with wait,
abstimed_wait, reltimed_wait, wake. They add documentation and error
checking according to the current draft of the Linux kernel futex manpage.
Waiting with absolute or relative timeouts is split into separate functions.
This allows for removing a few cases of code duplication in pthreads code,
which uses absolute timeouts; also, it allows us to put platform-specific
code to go from an absolute to a relative timeout into the platform-specific
futex abstractions..
Futex operations that can be canceled are also split out into separate
functions suffixed by "_cancelable".
There are separate versions for both Linux and NaCl; while they currently
differ only slightly, my expectation is that the separate versions of
lowlevellock-futex.h will eventually be merged into futex-internal.h
when we get to move the lll_ functions over to the new futex API.
This patch combines BUSY_WAIT_NOP and atomic_delay into a new
atomic_spin_nop function and adjusts all clients. The new function is
put into atomic.h because what is best done in a spin loop is
architecture-specific, and atomics must be used for spinning. The
function name is meant to tell users that this has no effect on
synchronization semantics but is a performance aid for spinning.
mq_notify (present in POSIX by 1996) brings in references to
pthread_barrier_init and pthread_barrier_wait (new in the 2001 edition
of POSIX). This patch fixes this by making those functions into weak
aliases of __pthread_barrier_*, exporting the __pthread_barrier_*
names at version GLIBC_PRIVATE and using them in mq_notify.
Tested for x86_64 and x86 (testsuite, and comparison of installed
stripped shared libraries). Changes in addresses from dynamic symbol
table / PLT changes render most comparisons not particularly useful,
but when the addresses of subsequent code don't change there's no sign
of unexpected changes there. This patch does not remove any
linknamespace XFAILs because of other namespace issues remaining with
mqueue.h functions.
[BZ #18544]
* nptl/pthread_barrier_init.c (pthread_barrier_init): Rename to
__pthread_barrier_init and define as weak alias of
__pthread_barrier_init.
* sysdeps/sparc/nptl/pthread_barrier_init.c
(pthread_barrier_init): Likewise.
* nptl/pthread_barrier_wait.c (pthread_barrier_wait): Rename to
__pthread_barrier_wait and define as weak alias of
__pthread_barrier_wait.
* sysdeps/sparc/nptl/pthread_barrier_wait.c
(pthread_barrier_wait): Likewise.
* sysdeps/sparc/sparc32/pthread_barrier_wait.c
(pthread_barrier_wait): Likewise.
* sysdeps/unix/sysv/linux/i386/i486/pthread_barrier_wait.S
(pthread_barrier_wait): Likewise.
* sysdeps/unix/sysv/linux/x86_64/pthread_barrier_wait.S
(pthread_barrier_wait): Likewise.
* nptl/Versions (libpthread): Export __pthread_barrier_init and
__pthread_barrier_wait at version GLIBC_PRIVATE.
* include/pthread.h (__pthread_barrier_init): Declare.
(__pthread_barrier_wait): Likewise.
* sysdeps/unix/sysv/linux/mq_notify.c (notification_function):
Call __pthread_barrier_wait instead of pthread_barrier_wait.
(helper_thread): Likewise.
(init_mq_netlink): Call __pthread_barrier_init instead of
pthread_barrier_init.
The sem_* functions bring in references to tdelete, tfind, tsearch and
twalk. But the t* functions are XSI-shaded, while sem_* aren't. This
patch fixes this by using __t* instead, exporting those functions from
libc at version GLIBC_PRIVATE (since sem_* are in libpthread) and
using libc_hidden_* for the benefit of calls within libc.
Tested for x86_64 and x86 (testsuite, and comparison of disassembly of
installed stripped shared libraries). libpthread gets changes from
PLT reordering; addresses in libc change because of PLT / dynamic
symbol table changes.
[BZ #18536]
* misc/tsearch.c (__tsearch): Use libc_hidden_def.
(__tfind): Likewise.
(__tdelete): Likewise.
(__twalk): Likewise.
* misc/Versions (libc): Add __tdelete, __tfind, __tsearch and
__twalk to GLIBC_PRIVATE.
* include/search.h (__tsearch): Use libc_hidden_proto.
(__tfind): Likewise.
(__tdelete): Likewise.
(__twalk): Likewise.
* nptl/sem_close.c (sem_close): Call __twalk instead of twalk.
Call __tdelete instead of tdelete.
* nptl/sem_open.c (check_add_mapping): Call __tfind instead of
tfind. Call __tsearch instead of tsearch.
* sysdeps/sparc/sparc32/sem_open.c (check_add_mapping): Likewise.
* conform/Makefile (test-xfail-POSIX/semaphore.h/linknamespace):
Remove variable.
(test-xfail-POSIX2008/semaphore.h/linknamespace): Likewise.
* sysdeps/sparc/sparc32/bits/atomic.h
(__sparc32_atomic_do_unlock24): Put the memory barrier before the
unlock not after it.
(__v9_compare_and_exchange_val_32_acq): Use unions to avoid getting
volatile register usage warnings from the compiler.
This sets __HAVE_64B_ATOMICS if provided. It also sets
USE_ATOMIC_COMPILER_BUILTINS to true if the existing atomic ops use the
__atomic* builtins (aarch64, mips partially) or if this has been
tested (x86_64); otherwise, this is set to false so that C11 atomics will
be based on the existing atomic operations.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch eliminates its use for _dl_init. Since _dl_init was already
declared with hidden visibility, creating a second hidden alias for it
was completely pointless, so this patch replaces all uses of
_dl_init_internal with plain _dl_init instead of using hidden_proto /
hidden_def (which are only needed when you want a hidden alias for a
non-hidden symbol; it's quite possible there are cases where they are
used but don't need to be because the symbol in question is not part
of the public ABI and is only used within a single library, so using
attributes_hidden instead would suffice).
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* elf/dl-init.c (_dl_init): Don't use INTDEF.
* sysdeps/aarch64/dl-machine.h (RTLD_START): Use _dl_init instead
of _dl_init_internal.
* sysdeps/alpha/dl-machine.h (RTLD_START): Likewise.
* sysdeps/arm/dl-machine.h (RTLD_START): Likewise.
* sysdeps/hppa/dl-machine.h (RTLD_START): Likewise.
* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
* sysdeps/ia64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/m68k/dl-machine.h (RTLD_START): Likewise.
* sysdeps/microblaze/dl-machine.h (RTLD_START): Likewise.
* sysdeps/mips/dl-machine.h (RTLD_START): Likewise.
* sysdeps/powerpc/powerpc32/dl-start.S (_start): Likewise.
* sysdeps/s390/s390-32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/s390/s390-64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sh/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/tile/dl-start.S (_start): Likewise.
* sysdeps/x86_64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/x86_64/x32/dl-machine.h (RTLD_START): Likewise.
This patch refactors how soft-fp comparisons handle setting exceptions
for NaN operands, so that exceptions are set through the FP_CMP macros
rather than directly in the C files calling them.
The _FP_CMP* and FP_CMP* macros gain an extra argument to specify when
exceptions should be set, 0 for no exception setting (I'm not sure
this is actually needed - at least it's not needed for IEEE operations
in glibc / libgcc, but might be relevant in some cases for kernel
use), 1 for exceptions only for signaling NaNs and 2 for exceptions
for all NaNs. This argument is handled through _FP_CMP_CHECK_NAN,
newly called by the _FP_CMP* macros when a NaN is encountered. Calls
to these macros are updated, which eliminates all the existing
checking and exception setting in soft-fp *.c files in glibc.
Tested for powerpc-nofpu. (The __unord* functions have no code
changes; the __eq* / __ge* / __le* functions get slightly larger, but
I don't think that's significant.)
* soft-fp/op-common.h (_FP_CMP_CHECK_NAN): New macro.
(_FP_CMP): Add extra argument EX. Call _FP_CMP_CHECK_NAN.
(_FP_CMP_EQ): Likewise.
(_FP_CMP_UNORD): Likewise.
* soft-fp/double.h (FP_CMP_D): Add extra argument EX.
(FP_CMP_EQ_D): Likewise.
(FP_CMP_UNORD_D): Likewise.
* soft-fp/extended.h (FP_CMP_E): Likewise.
(FP_CMP_EQ_E): Likewise.
(FP_CMP_UNORD_E): Likewise.
* soft-fp/quad.h (FP_CMP_Q): Likewise.
(FP_CMP_EQ_Q): Likewise.
(FP_CMP_UNORD_Q): Likewise.
* soft-fp/single.h (FP_CMP_S): Likewise.
(FP_CMP_EQ_S): Likewise.
(FP_CMP_UNORD_S): Likewise.
* soft-fp/eqdf2.c (__eqdf2): Update call to FP_CMP_EQ_D.
* soft-fp/eqsf2.c (__eqsf2): Update call to FP_CMP_EQ_S.
* soft-fp/eqtf2.c (__eqtf2): Update call to FP_CMP_EQ_Q.
* soft-fp/gedf2.c (__gedf2): Update call to FP_CMP_D.
* soft-fp/gesf2.c (__gesf2): Update call to FP_CMP_S.
* soft-fp/getf2.c (__getf2): Update call to FP_CMP_Q.
* soft-fp/ledf2.c (__ledf2): Update call to FP_CMP_D.
* soft-fp/lesf2.c (__lesf2): Update call to FP_CMP_S.
* soft-fp/letf2.c (__letf2): Update call to FP_CMP_Q.
* soft-fp/unorddf2.c (__unorddf2): Update call to FP_CMP_UNORD_D.
* soft-fp/unordsf2.c (__unordsf2): Update call to FP_CMP_UNORD_S.
* soft-fp/unordtf2.c (__unordtf2): Update call to FP_CMP_UNORD_Q.
* sysdeps/alpha/soft-fp/ots_cmpe.c (internal_compare): Update call
to FP_CMP_Q.
* sysdeps/sparc/sparc32/soft-fp/q_cmp.c (_Q_cmp): Update call to
FP_CMP_Q.
* sysdeps/sparc/sparc32/soft-fp/q_cmpe.c (_Q_cmpe): Likewise.
* sysdeps/sparc/sparc32/soft-fp/q_feq.c (_Q_feq): Update call to
FP_CMP_EQ_Q.
* sysdeps/sparc/sparc32/soft-fp/q_fge.c (_Q_fge): Update call to
FP_CMP_Q.
* sysdeps/sparc/sparc32/soft-fp/q_fgt.c (_Q_fgt): Likewise.
* sysdeps/sparc/sparc32/soft-fp/q_fle.c (_Q_fle): Likewise.
* sysdeps/sparc/sparc32/soft-fp/q_flt.c (_Q_flt): Likewise.
* sysdeps/sparc/sparc32/soft-fp/q_fne.c (_Q_fne): Update call to
FP_CMP_EQ_Q.
* sysdeps/sparc/sparc64/soft-fp/qp_cmp.c (_Qp_cmp): Update call to
FP_CMP_Q.
* sysdeps/sparc/sparc64/soft-fp/qp_cmpe.c (_Qp_cmpe): Likewise.
* sysdeps/sparc/sparc64/soft-fp/qp_feq.c (_Qp_feq): Update call to
FP_CMP_EQ_Q.
* sysdeps/sparc/sparc64/soft-fp/qp_fge.c (_Qp_fge): Update call to
FP_CMP_Q.
* sysdeps/sparc/sparc64/soft-fp/qp_fgt.c (_Qp_fgt): Likewise.
* sysdeps/sparc/sparc64/soft-fp/qp_fle.c (_Qp_fle): Likewise.
* sysdeps/sparc/sparc64/soft-fp/qp_flt.c (_Qp_flt): Likewise.
* sysdeps/sparc/sparc64/soft-fp/qp_fne.c (_Qp_fne): Update call to
FP_CMP_EQ_Q.
As noted in
<https://sourceware.org/ml/libc-alpha/2013-10/msg00516.html>, the
soft-fp macro FP_CLEAR_EXCEPTIONS should not be necessary, as soft-fp
code should never set an exception and later clear it.
In fact, all four uses in glibc (for SPARC) are indeed unnecessary:
they appear in files that convert 32-bit or 64-bit integers to IEEE
binary128, an operation that can never raise any exceptions. If this
was intended to enable the compiler to optimize away any FP_FROM_INT
code testing for exceptional cases, we now have a better way of doing
this: defining FP_NO_EXCEPTIONS before including soft-fp.h causes all
code handling exceptions to be stubbed out, and the rounding mode to
be hardwired for round-to-zero, to allow such optimizations for source
files where (a) the operation in question, for the particular types in
question, can never raise exceptions, but (b) some instances of the
operation for other types can, so the macros used in the file do
contain references to rounding or exceptions, albeit dead in that
particular file.
The uses in the Linux kernel are also unnecessary (clearing exceptions
at a point where they are already cleared).
This patch duly removes FP_CLEAR_EXCEPTIONS, making the SPARC code in
question use FP_NO_EXCEPTIONS and stop using exception-related macros.
* soft-fp/soft-fp.h (FP_CLEAR_EXCEPTIONS): Remove macro.
* sysdeps/sparc/sparc32/soft-fp/q_itoq.c: Define FP_NO_EXCEPTIONS.
(_Q_itoq): Do not use FP_DECL_EX, FP_CLEAR_EXCEPTIONS or
FP_HANDLE_EXCEPTIONS.
* sysdeps/sparc/sparc32/soft-fp/q_lltoq.c: Define FP_NO_EXCEPTIONS.
(_Q_lltoq): Do not use FP_DECL_EX, FP_CLEAR_EXCEPTIONS or
FP_HANDLE_EXCEPTIONS.
* sysdeps/sparc/sparc32/soft-fp/q_ulltoq.c: Define FP_NO_EXCEPTIONS.
(_Q_ulltoq): Do not use FP_DECL_EX, FP_CLEAR_EXCEPTIONS or
FP_HANDLE_EXCEPTIONS.
* sysdeps/sparc/sparc32/soft-fp/q_utoq.c: Define FP_NO_EXCEPTIONS.
(_Q_utoq): Do not use FP_DECL_EX, FP_CLEAR_EXCEPTIONS or
FP_HANDLE_EXCEPTIONS.
This patch defines ELF_MACHINE_NO_RELA on all architectures. Tested
only on x86_64 to verify that the sources before and after are
identical except for two instructions that pass the current line
number in dl-machine.h to assert_fail.
IEEE 754-2008 defines two ways in which tiny results can be detected,
"before rounding" (based on the infinite-precision result) and "after
rounding" (based on the result when rounded to normal precision as if
the exponent range were unbounded). All binary operations on an
architecture must use the same choice of how tininess is detected.
soft-fp has so far implemented only before-rounding tininess
detection. This patch adds support for after-rounding tininess
detection. A new macro _FP_TININESS_AFTER_ROUNDING is added that
sfp-machine.h must define (soft-fp is meant to be self-contained so
the existing tininess.h files aren't used here, though the information
going in sfp-machine.h has been taken from them). The soft-fp macros
dealing with raising underflow exceptions then handle the cases where
the choice matters specially, rounding a copy of the input to the
appropriate precision to see if a value that's tiny before rounding
isn't tiny after rounding.
Tested for mips64 using GCC trunk (which now uses soft-fp on MIPS, so
supporting exceptions and rounding modes for long double where not
previously supported - this is the immediate motivation for doing this
patch now) together with (a) a patch to sysdeps/mips/math-tests.h to
enable exceptions / rounding modes tests for long double for GCC 4.9
and later, and (b) corresponding changes applied to libgcc's soft-fp
and sfp-machine.h files. In the libgcc context this is also tested on
x86_64 (also an after-rounding architecture) with testcases for
__float128 that I intend to add to the GCC testsuite when updating
soft-fp there.
(To be clear: this patch does not fix any glibc bugs that were
user-visible in past releases, since after-rounding architectures
didn't use soft-fp in any affected case with support for
floating-point exceptions - so there is no corresponding Bugzilla bug.
Rather, it works together with the GCC changes to use soft-fp on MIPS
to allow previously absent long double functionality to work properly,
and allows soft-fp to be used in glibc on after-rounding architectures
in cases where it couldn't previously be used.)
* soft-fp/op-common.h (_FP_DECL): Mark exponent as possibly
unused.
(_FP_PACK_SEMIRAW): Determine tininess based on rounding shifted
value if _FP_TININESS_AFTER_ROUNDING and unrounded value is in
subnormal range.
(_FP_PACK_CANONICAL): Determine tininess based on rounding to
normal precision if _FP_TININESS_AFTER_ROUNDING and unrounded
value has largest subnormal exponent.
* soft-fp/soft-fp.h [FP_NO_EXCEPTIONS]
(_FP_TININESS_AFTER_ROUNDING): Undefine and redefine to 0.
* sysdeps/aarch64/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): New macro.
* sysdeps/alpha/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): Likewise.
* sysdeps/arm/soft-fp/sfp-machine.h (_FP_TININESS_AFTER_ROUNDING):
Likewise.
* sysdeps/mips/mips64/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): Likewise.
* sysdeps/mips/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): Likewise.
* sysdeps/powerpc/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): Likewise.
* sysdeps/sh/soft-fp/sfp-machine.h (_FP_TININESS_AFTER_ROUNDING):
Likewise.
* sysdeps/sparc/sparc32/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): Likewise.
* sysdeps/sparc/sparc64/soft-fp/sfp-machine.h
(_FP_TININESS_AFTER_ROUNDING): Likewise.
* sysdeps/tile/sfp-machine.h (_FP_TININESS_AFTER_ROUNDING):
Likewise.
We cannot use fnegd in this code, as fnegd was added in v9.
Only fnegs exists in v8 and earlier.
[BZ #15985]
* sysdeps/sparc/sparc32/fpu/s_fdim.S (__fdim): Do not use fnegd
on pre-v9 cpus, use a fnegs+fmovs sequence instead.
The pointer guard used for pointer mangling was not initialized for
static applications resulting in the security feature being disabled.
The pointer guard is now correctly initialized to a random value for
static applications. Existing static applications need to be
recompiled to take advantage of the fix.
The test tst-ptrguard1-static and tst-ptrguard1 add regression
coverage to ensure the pointer guards are sufficiently random
and initialized to a default value.
Resolves: #15465
The program name may be unavailable if the user application tampers
with argc and argv[]. Some parts of the dynamic linker caters for
this while others don't, so this patch consolidates the check and
fallback into a single macro and updates all users.
[BZ #15442] This adds support for the inverse interpretation of the
quiet bit of IEEE 754 floating-point NaN data that some processors
use. This includes in particular MIPS architecture processors; the
payload used for the canonical qNaN encoding is updated accordingly
so as not to interfere with the quiet bit.
* sysdeps/sparc/sparc32/sparcv9/bits/atomic.h
(__arch_compare_and_exchange_val_32_acq): Use %g0 as second
argument of CAS if possible.
* sysdeps/sparc/sparc64/bits/atomic.h
(__arch_compare_and_exchange_val_32_acq): Likewise.
(__arch_compare_and_exchange_val_64_acq): Likewise.