Improve fesetenv to use an optimized implementation similar to
feupdateenv.
2014-06-24 Wilco <wdijkstr@arm.com>
* sysdeps/arm/fesetenv.c (fesetenv): Optimize implementation.
This patch rewrites feupdateenv to improve performance by avoiding
unnecessary FPSCR reads/writes. It fixes bug 16918 by passing the
correct return value.
2014-06-24 Wilco <wdijkstr@arm.com>
[BZ #16918]
* sysdeps/arm/feupdateenv.c (feupdateenv):
Rewrite to reduce FPSCR accesses and fix return value.
rather than duplicating functionality. To make this work for softfp builds,
ensure functions in fenv_private are not conditionally compiled.
2014-06-24 Wilco <wdijkstr@arm.com>
* sysdeps/arm/fegetround.c (fegetround): Call get_rounding_mode.
* sysdeps/arm/feholdexcpt.c (feholdexcept): Call libc_feholdexcept_vfp.
* sysdeps/arm/fesetround.c (fesetround): Call libc_fesetround_vfp.
* sysdeps/arm/fgetexcptflg.c (fegetexceptflag):
Call libc_fetestexcept_vfp.
* sysdeps/arm/ftestexcept.c (fetestexcept): Call libc_fetestexcept_vfp.
* sysdeps/arm/fenv_private.h: Move libc_*_vfp functions outside of
__SOFTFP__ ifdef so that they can be built for softfp.
This fixes the calculation of R_ARM_TLS_DESC relocations for lazy global
symbol references, i.e. created with `-z lazy' in effect with the static
linker, where immediate resolution is requested with LD_BIND_NOW.
This patch relies on the C version of the rwlocks posted earlier.
With C rwlocks it is very straight forward to do adaptive elision
using TSX. It is based on the infrastructure added earlier
for mutexes, but uses its own elision macros. The macros
are fairly general purpose and could be used for other
elision purposes too.
This version is much cleaner than the earlier assembler based
version, and in particular implements adaptation which makes
it safer.
I changed the behavior slightly to not require any changes
in the test suite and fully conform to all expected
behaviors (generally at the cost of not eliding in
various situations). In particular this means the timedlock
variants are not elided. Nested trylock aborts.
The current code for handling concurrent resolution says that the
ABI for _dl_tlsdesc_resolve_hold is the same as that of
_dl_tlsdesc_lazy_resolver. However _dl_tlsdesc_resolve_hold is
called from the trampoline directly rather than the lazy resolver
stub so, for example, r2 has not been pushed so does not needed
to be restored.
This fixes an intermittent failure in nptl/tst-tls3 when building
glibc for arm-linux-gnueabihf with -mtls-dialect=gnu2.
ChangeLog:
2014-05-27 Will Newton <will.newton@linaro.org>
[BZ #16990]
* sysdeps/arm/dl-tlsdesc.S (_dl_tlsdesc_resolve_hold): Save
and restore r2 rather than just restoring.
As previously noted
<https://sourceware.org/ml/libc-alpha/2013-05/msg00696.html>,
$(elf-objpfx) and $(elfobjdir) are redundant and should be
consolidated. This patch consolidates on $(elf-objpfx) (for
consistency with $(csu-objpfx)), also changing direct uses of
$(common-objpfx)elf/ to use $(elf-objpfx).
Tested x86_64, including that installed shared libraries are unchanged
by the patch.
* Makeconfig [$(build-hardcoded-path-in-tests) = yes]
(rtld-tests-LDFLAGS): Use $(elf-objpfx) instead of
$(common-objpfx)elf/.
(link-libc-before-gnulib): Likewise.
(elfobjdir): Remove variable.
* Makefile (install): Use $(elf-objpfx) instead of
$(common-objpfx)elf/.
* Makerules (link-libc-args): Use $(elf-objpfx) instead of
$(elfobjdir)/.
(link-libc-deps): Likewise.
($(common-objpfx)libc.so): Likewise.
($(common-objpfx)linkobj/libc.so): Likewise.
[$(cross-compiling) = no] (symbolic-link-prog): Use $(elf-objpfx)
instead of $(common-objpfx)elf/.
(symbolic-link-list): Likewise.
* iconvdata/Makefile ($(inst_gconvdir)/gconv-modules)
[$(cross-compiling) = no]: Likewise.
* sysdeps/arm/Makefile (gnulib-arch): Use $(elf-objpfx) instead of
$(elfobjdir)/.
(static-gnulib-arch): Likewise.
* sysdeps/s390/s390-64/Makefile ($(inst_gconvdir)/gconv-modules)
[$(cross-compiling) = no]: Use $(elf-objpfx) instead of
$(common-objpfx)elf/.
localedata/ChangeLog:
* Makefile (LOCALEDEF): Use $(elf-objpfx) instead of
$(common-objpfx)elf/.
Commit 7d92b78723 [Fix ARM NAN fraction
bits.] removed all the bits set from NANFRAC macros and, when propagated
to libgcc, regressed gcc.dg/torture/builtin-math-7.c on soft-fp arm-eabi
targets, currently ARMv6-M (`-march=armv6-m -mthumb') only. This is
because when used to construct a NaN in the semi-raw mode, they now
build an infinity instead. Consequently operations such as (Inf - Inf)
now produce Inf rather than NaN. The change worked for the original
test case, posted with PR libgcc/60166, because division is made in the
canonical mode, where the quiet bit is set separately, from the fp
class.
This change brings the quiet bit back to these macros, making semi-raw
mode calculations produce the expected results again.
This patch cleans up some symbol versioning code in the ARM port that
exists only as relics of the old-ABI port, which was removed some time
ago.
The minimum symbol version in the ARM port is GLIBC_2.4 (the version
where the EABI port was introduced). Thus, any SHLIB_COMPAT
conditionals where the later version is 2.4 or later are obsolete and
can be removed. In addition, there is no need to set symbol versions
before 2.4 explicitly if the symbols would have a version of 2.4 by
default anyway. This includes most of the entries in
sysdeps/unix/sysv/linux/arm/Versions: those for GLIBC_2.0 are for
libgcc unwind functions that aren't actually in ARM EABI glibc at all,
while those for GLIBC_2.2 and GLIBC_2.3.3 are for functions which for
the old-ABI port may have had versions different from the
architecture-independent default, but where for EABI the default
suffices (both the default and the version in that file map to 2.4, so
the entries in that file do nothing). The GLIBC_2.1 entries are
needed (architecture-specific functions), but it seems less confusing
for those to say GLIBC_2.4, as the actual version those symbols in
fact have.
Various cases in the <fenv.h> functions where a function is defined as
__fe* with an fe* versioned alias are cleaned up just to define fe*
directly, as done e.g. on AArch64. If in future we actually need an
__fe* name for use from C90 functions in libm as discussed recently,
of course we can add one on all architectures and make the fe* name
into a weak alias for that particular function, but for now the __fe*
names aren't needed.
In the case of posix_fadvise64, the __posix_fadvise64_l64 name and
posix_fadvise64 alias are kept as __posix_fadvise64_l64 is used in
posix_fadvise. (For that to be a namespace-clean use, posix_fadvise64
needs to be a *weak* alias not a strong one as at present, but that's
an independent preexisting bug.)
(There remain references to GLIBC_2_2 in
sysdeps/unix/sysv/linux/arm/{msgctl.c,semctl.c,shmctl.c}. As those
files are used by alpha which has a genuine 2.2 version for those
functions, I think those references need to stay as-is.)
Tested that the disassembly of installed shared libraries is unchanged
by this patch (though function names shown in disassembly change to no
longer have @@GLIBC_2.4, now those functions get versioned only by the
version map and not redundantly at assembler time) and that the ABI
tests pass.
* sysdeps/arm/fclrexcpt.c (__feclearexcept): Rename to
feclearexcept. Remove symbol versioning code.
* sysdeps/arm/fegetenv.c (__fegetenv): Rename to fegetenv. Remove
symbol versioning code.
* sysdeps/arm/fesetenv.c (__fesetenv): Rename to fesetenv. Remove
symbol versioning code.
* sysdeps/arm/feupdateenv.c (__feupdateenv): Rename to
feupdateenv. Remove symbol versioning code.
* sysdeps/arm/fgetexcptflg.c (__fegetexceptflag): Rename to
fegetexceptflag. Remove symbol versioning code.
* sysdeps/arm/fsetexcptflg.c (__fesetexceptflag): Rename to
fesetexceptflag. Remove symbol versioning code.
* sysdeps/unix/sysv/linux/arm/Versions (libc): Remove GLIBC_2.0,
GLIBC_2.2 and GLIBC_2.3.3 entries. Change GLIBC_2.1 to GLIBC_2.4.
* sysdeps/unix/sysv/linux/arm/posix_fadvise64.c
(__posix_fadvise64_l32): Remove prototype.
[SHLIB_COMPAT(libc, GLIBC_2_2, GLIBC_2_3_3)]: Remove conditional
code.
Set values for libc_commonpagesize and libc_relro_required for the
ARM port to enable relro by default and suppress a warning at
configure time.
ChangeLog:
2014-05-09 Will Newton <will.newton@linaro.org>
* sysdeps/arm/preconfigure.ac: Set libc_commonpagesize
and libc_relro_required for ARM.
* sysdeps/arm/preconfigure: Regenerate.
Add an optimized implementation of strcmp for ARMv7-A cores. This
implementation is significantly faster than the current generic C
implementation, particularly for strings of 16 bytes and longer.
Tested with the glibc string tests for arm-linux-gnueabihf and
armeb-linux-gnueabihf.
The code was written by ARM, who have agreed to assign the copyright
to the FSF for integration into glibc.
ChangeLog:
2014-05-09 Will Newton <will.newton@linaro.org>
* sysdeps/arm/armv7/strcmp.S: New file.
* NEWS: Mention addition of ARMv7 optimized strcmp.
This patch fixes what I believe to be a bug in the handling of
R_ARM_IRELATIVE RELA relocations. At present, these are handled the
same as REL relocations: i.e. the addend is loaded from the relocation
address. Most of the time this isn't a problem because RELA relocations
aren't used on ARM (GNU/Linux at least) anyway, but it causes problems
with prelink, which uses RELA on all targets for its conflict table.
(Support for ifunc prelinking requires a prelink patch, not yet posted.)
Anyway, this patch works, though I'm not 100% sure if it is correct: I
notice that this code path received attention last year:
https://sourceware.org/ml/libc-ports/2013-07/msg00000.html
I'm not sure under what circumstances that patch would have had an
effect, nor if my patch conflicts with that case.
No regressions using Mentor's usual glibc cross-testing infrastructure.
[BZ #16888]
* sysdeps/arm/dl-machine.h (elf_machine_rela): Fix R_ARM_IRELATIVE
handling.
As recently discussed
<https://sourceware.org/ml/libc-alpha/2014-02/msg00670.html>, it
doesn't seem particularly useful for libm-test-ulps files to contain
huge amounts of data on ulps for individual tests; just the global
maximum observed ulps for each function, together with the
verification of exceptions, errno and special results such as
infinities and NaNs for each test, suffices to verify that a
function's behavior on the given test inputs is within the expected
accuracy. Removing this data reduces source tree churn caused by
updates to these files when libm tests are added, and reduces the
frequency with which testsuite additions actually need libm-test-ulps
changes at all.
Accordingly, this patch removes that data, so that individual tests
get checked against the global bounds for the given function and only
generate an error if those are exceeded. Tested x86_64 (including
verifying that if an ulps value is artificially reduced, the tests do
indeed fail as they should and "make regen-ulps" generates the
expected changes).
* math/libm-test.inc (struct ulp_data): Don't refer to ulps for
individual tests in comment.
(libm-test-ulps.h): Don't refer to test_ulps in #include comment.
(prev_max_error): New variable.
(prev_real_max_error): Likewise.
(prev_imag_max_error): Likewise.
(compare_ulp_data): Don't refer to test names in comment.
(find_test_ulps): Remove function.
(find_function_ulps): Likewise.
(find_complex_function_ulps): Likewise.
(init_max_error): Take function name as argument. Look up ulps
for that function.
(print_ulps): Remove function.
(print_max_error): Use prev_max_error instead of calling
find_function_ulps.
(print_complex_max_error): Use prev_real_max_error and
prev_imag_max_error instead of calling find_complex_function_ulps.
(check_float_internal): Take max_ulp parameter instead of calling
find_test_ulps. Don't call print_ulps.
(check_float): Update call to check_float_internal.
(check_complex): Update calls to check_float_internal.
(START): Pass argument to init_max_error.
* math/gen-libm-test.pl (%results): Don't include "kind"
information.
(parse_ulps): Don't handle ulps of individual tests.
(print_ulps_file): Likewise.
(output_ulps): Likewise.
* math/README.libm-test: Update.
* manual/libm-err-tab.pl (parse_ulps): Don't handle ulps of
individual tests.
* sysdeps/aarch64/libm-test-ulps: Remove individual test ulps.
* sysdeps/alpha/fpu/libm-test-ulps: Likewise.
* sysdeps/arm/libm-test-ulps: Likewise.
* sysdeps/i386/fpu/libm-test-ulps: Likewise.
* sysdeps/ia64/fpu/libm-test-ulps: Likewise.
* sysdeps/m68k/coldfire/fpu/libm-test-ulps: Likewise.
* sysdeps/m68k/m680x0/fpu/libm-test-ulps: Likewise.
* sysdeps/microblaze/libm-test-ulps: Likewise.
* sysdeps/mips/mips32/libm-test-ulps: Likewise.
* sysdeps/mips/mips64/libm-test-ulps: Likewise.
* sysdeps/powerpc/fpu/libm-test-ulps: Likewise.
* sysdeps/powerpc/nofpu/libm-test-ulps: Likewise.
* sysdeps/s390/fpu/libm-test-ulps: Likewise.
* sysdeps/sh/libm-test-ulps: Likewise.
* sysdeps/sparc/fpu/libm-test-ulps: Likewise.
* sysdeps/tile/libm-test-ulps: Likewise.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
* sysdeps/hppa/fpu/libm-test-ulps: Remove individual test ulps.
Current ARM soft-float implementation is violating the RTABI
(http://infocenter.arm.com/help/topic/com.arm.doc.ihi0043d/IHI0043D_rtabi.pdf)
Section 4.1.1.1:
When not otherwise specified by IEEE 754, the result on an invalid
operation should be the quiet NaN bit pattern with only the most
significant bit of the significand set, and all other significand bits
zero.
This patch fixes it by setting _FP_NANFRAC_* to zero.
Ran make check test with -mfloat-abi=soft. No regression.
* sysdeps/arm/soft-fp/sfp-machine.h (_FP_NANFRAC_S, _FP_NANFRAC_D)
(_FP_NANFRAC_Q): Set to zero.
Now the ARM port implements pointer encryption for jmpbufs, gdb needs
a SystemTap probe point in longjmp to determine the target PC of
a call to longjmp. This patch implements the probe point in longjmp
and a similar probe point in setjmp.
In order to have all the appropriate registers available to pass to the
probe this reorders the layout of jmpbuf, putting the sp and lr registers
at the start rather than the end, allowing them to be read and
written sequentially.
Tested on armv7, no new failures in the glibc testsuite and confirmed
that this fixes the gdb.base/longjmp.exp failures in the gdb testsuite.
ChangeLog:
2014-02-25 Will Newton <will.newton@linaro.org>
* sysdeps/arm/__longjmp.S: Include stap-probe.h.
(__longjmp): Restore sp and lr before restoring callee
saved registers. Add longjmp and longjmp_target
SystemTap probe point.
* sysdeps/arm/bits/setjmp.h (__jmp_buf): Update comment.
* sysdeps/arm/include/bits/setjmp.h (__JMP_BUF_SP):
Define to zero to match jmpbuf layout.
* sysdeps/arm/setjmp.S: Include stap-probe.h.
(__sigsetjmp): Save sp and lr before saving callee
saved registers. Add setjmp SystemTap probe point.
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.
I've moved the ARM port from ports to the main sysdeps hierarchy.
Beyond the README update, the move of the files was simply
git mv ports/sysdeps/arm sysdeps/arm
git mv ports/sysdeps/unix/arm sysdeps/unix/arm
git mv ports/sysdeps/unix/sysv/linux/arm sysdeps/unix/sysv/linux/arm
and in addition to the ChangeLog entries here, I put a note at the top
of ports/ChangeLog.arm similar to that at the top of
ChangeLog.powerpc. There is deliberately no NEWS change, as I think
it makes the most sense to put in a general note above all ports
having moved if we can achieve that for 2.20.
Tested that disassembly of installed shared libraries for arm is the
same before and after this patch, except for data (not instructions)
in ld.so (there are assertions in sysdeps/arm/dl-machine.h, and the
path by which that file is found, and so by which it appears in the
assertion message, changes as a result of the move).
* sysdeps/arm: Move directory from ports/sysdeps/arm.
* sysdeps/unix/arm: Move directory from ports/sysdeps/unix/arm.
* sysdeps/unix/sysv/linux/arm: Move directory from
ports/sysdeps/unix/sysv/linux/arm.
* README: Update listing for arm-*-linux-gnueabi.
ports/ChangeLog.arm:
* sysdeps/arm: Move directory to ../sysdeps/arm.
* sysdeps/unix/arm: Move directory to ../sysdeps.arm.
* sysdeps/unix/sysv/linux/arm: Move directory to
../sysdeps/unix/sysv/linux/arm.
Use it instead of __THUMB_INTERWORK__. Make RETINSTR take
only a condition and a register.
* sysdeps/arm/dl-machine.h: Use __USE_BX__ instead of
__THUMB_INTERWORK__.
(_dl_start_user): Use BX.
* sysdeps/arm/strlen.S: Use DO_RET.
* sysdeps/unix/arm/brk.S, sysdeps/unix/arm/fork.S,
sysdeps/unix/arm/sysdep.S, sysdeps/unix/arm/sysdep.h: Likewise.
* sysdeps/unix/sysv/linux/arm/clone.S,
sysdeps/unix/sysv/linux/arm/mmap.S,
sysdeps/unix/sysv/linux/arm/mmap64.S,
sysdeps/unix/sysv/linux/arm/socket.S,
sysdeps/unix/sysv/linux/arm/sysdep.h,
sysdeps/unix/sysv/linux/arm/vfork.S: Update uses of RETINSTR.
2004-04-29 Philip Blundell <pb@nexus.co.uk>
* sysdeps/arm/dl-machine.h (RTLD_START): Avoid unnecessary GOT
entries.
[BZ #140]
* sysdeps/unix/sysv/linux/sys/sysctl.h: Remove linux/compiler.h
include.
(_LINUX_KERNEL_H, _LINUX_TYPES_H, _LINUX_LIST_H): Only define if not
yet defined, #undef back after including linux/sysctl.h if defined
here.
(__LINUX_COMPILER_H, __user): Define if not yet defined, #undef
back after including linux/sysctl.h if defined here.
