When stack is re-aligned in _dl_runtime_resolve, there is no need to
adjust CFA when allocating register save area on stack.
* sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve): Don't
adjust CFA when allocating register save area on re-aligned
stack.
A tsearch red-black tree node contains 3 pointers (key, left, right)
and 1 bit to hold the red-black flag. When allocating new nodes
this 1 bit is expanded to a full word. Causing the overhead per node
to be 3 times the key size.
We can reduce this overhead to just 2 times the key size.
malloc returns naturally aligned memory. All nodes are internally
allocated with malloc and the left/right node pointers are used
as implementation details. So we can use the low bits of the
left/right node pointers to store extra information.
Replace all direct accesses of the struct node_t node pointers and
red-black value with defines that take care of the red-black flag in
the low bit of the (left) node pointer. This reduces the size of the
nodes on 32-bit systems from 16 to 12 bytes and on 64-bit systems
from 32 to 24 bytes.
Also fix a call to CHECK_TREE so the code can be build (and tested)
with DEBUGGING defined again.
V2 changes:
- Add assert after malloc to catch any odd pointers from bad
interposed mallocs.
- Rename implementation flag to USE_MALLOC_LOW_BIT.
ChangeLog:
* misc/tsearch.c (struct node_t): Reduce to 3 pointers if
USE_MALLOC_LOW_BIT. Define pointer/value accessors.
(check_tree_recurse): Use newly defined accessors.
(check_tree): Likewise.
(maybe_split_for_insert): Likewise.
(__tfind): Likewise.
(__tdelete): Likewise.
(trecurse): Likewise.
(tdestroy_recurse): Likewise.
(__tsearch): Likewise. And add asserts for malloc alignment.
(__twalk): Cast root to node in case CHECK_TREE is defined.
This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.
This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.
All other state bits, except for bit_YMM_state, are defined as (1 << N).
This patch changes bit_YMM_state from (2 << 1) to (1 << 2).
* sysdeps/x86/cpu-features.h (bit_YMM_state): Set to (1 << 2).
A number of files share identical code for the
mul_split function.
This moves the duplicated function mul_split into its
own header, and refactors the fma usage into a single
selection macro. Likewise, mul_split when used by a
long double implementation is renamed mul_splitl for
clarity.
This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.
This extends tst-strtod-round with a few trivial changes
to also test the wide character variants of strto* using
similar macros to other shared tests.
_res_hconf.initialized was not suitable for use in a multi-threaded
environment due to the lack of atomics and memory barriers. Use of it was
also unnecessary because _res_hconf_init did the right thing by using
__libc_once. This patch fixes the glibc-internal uses by just calling
_res_hconf_init unconditionally, and switches to a release MO atomic store
for _res_hconf.initialized to fix the glibc side of the synchronization
problem (which will maintain backward compatibility, but cannot fix the
lack of acquire MO on any glibc-external loads).
[BZ #20477]
* resolv/res_hconf.c (do_init): Use atomic access.
* resolv/res_hconf.h: Add comments.
* nscd/aicache.c (addhstaiX): Call _res_hconf_init unconditionally.
* nss/getXXbyYY_r.c (REENTRANT_NAME): Likewise.
* sysdeps/posix/getaddrinfo.c (gaih_inet): Likewise.
On s390x I get the following werror when build with gcc 6.1 (or current gcc head) and -O3:
../sysdeps/ieee754/dbl-64/k_rem_pio2.c: In function ‘__kernel_rem_pio2’:
../sysdeps/ieee754/dbl-64/k_rem_pio2.c:254:18: error: array subscript is below array bounds [-Werror=array-bounds]
for (k = 1; iq[jk - k] == 0; k++)
~~^~~~~~~~
I get the same error with sysdeps/ieee754/flt-32/k_rem_pio2f.c.
This patch adds DIAG_* macros around it.
ChangeLog:
* sysdeps/ieee754/dbl-64/k_rem_pio2.c (__kernel_rem_pio2):
Use DIAG_*_NEEDS_COMMENT macro to get rid of array-bounds warning.
* sysdeps/ieee754/flt-32/k_rem_pio2f.c (__kernel_rem_pio2f):
Likewise.
glibc provides fallback definitions already. It is not necessary to
suppress warnings for unknown attributes because GCC does this
automatically for system headers.
This commit does not sync with gnulib because gnulib has started to use
_GL_* macros in the header file, which are arguably in the gnulib
implementation space and not suitable for an installed glibc header
file.
This defines a new classes of libm objects. The
<func>_template.c file which is used in conjunction
with the new makefile hooks to derive variants for
each type supported by the target machine.
The headers math-type-macros-TYPE.h are used to supply
macros to a common implementation of a function in
a file named FUNC_template.c and glued togethor via
a generated file matching existing naming in the
build directory.
This has the properties of preserving the existing
override mechanism and not requiring any arcane
build system twiddling. Likewise, it enables machines
to override these files without any additional work.
I have verified the built objects for ppc64, x86_64,
alpha, arm, and m68k do not change in any meaningful
way with these changes using the Fedora cross toolchains.
I have verified the x86_64 and ppc64 changes still run.
soft-fp unpacking for x86 "extended" fails to clear the implicit
mantissa high bit that is explicit in that format, resulting in
problems for operations that expect this bit to be clear in raw
unpacked values. Specifically, the code for this format is used only
for conversions to and from TFmode (__float128) in libgcc, where this
issue results in GCC bug 77265, extension of long double infinity to
__float128 wrongly produces a NaN.
This patch fixes this by always masking out the implicit bit on
unpacking, so that the results of unpacking meet the expectations of
the rest of the soft-fp code for a normal IEEE format.
Tested for x86_64 in libgcc in conjunction with a GCC testcase for
this issue (this code isn't used in glibc, only in libgcc).
* soft-fp/extended.h [_FP_W_TYPE_SIZE < 64] (FP_UNPACK_RAW_E):
Mask implicit bit out of unpacked value.
[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_RAW_EP): Likewise.
[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_RAW_E): Likewise.
[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_RAW_EP): Likewise.
TS 18661-1 defines an fesetexcept function for setting floating-point
exception flags without the side-effect of causing enabled traps to be
taken.
This patch series implements this function for glibc. The present
patch adds the fallback stub implementation, x86 and x86_64
implementations, documentation, tests and ABI baseline updates. The
remaining patches, some of them untested, add implementations for
other architectures. The implementations generally follow those of
the fesetexceptflag function.
As for fesetexceptflag, the approach taken for architectures where
setting flags causes enabled traps to be taken is to set the flags
(and potentially cause traps) rather than refusing to set the flags
and returning an error. Since ISO C and TS 18661 provide no way to
enable traps, this is formally in accordance with the standards.
The NEWS entry should be considered a placeholder, since this patch
series is intended to be followed by further such series adding other
TS 18661-1 features, so that the NEWS entry would end up looking more
like
* New <fenv.h> features from TS 18661-1:2014 are added to libm: the
fesetexcept, fetestexceptflag, fegetmode and fesetmode functions,
the femode_t type and the FE_DFL_MODE macro.
with hopefully more such entries for other features, rather than
having an entry for a single function in the end.
I believe we have consensus for adding TS 18661-1 interfaces as per
<https://sourceware.org/ml/libc-alpha/2016-06/msg00421.html>.
Tested for x86_64, x86, mips64 (hard float, and soft float to test the
fallback version), arm (hard float) and powerpc (hard float, soft
float and e500).
* math/fesetexcept.c: New file.
* sysdeps/i386/fpu/fesetexcept.c: Likewise.
* sysdeps/x86_64/fpu/fesetexcept.c: Likewise.
* math/fenv.h: Define
__GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION and include
<bits/libc-header-start.h> instead of including <features.h>.
[__GLIBC_USE (IEC_60559_BFP_EXT)] (fesetexcept): New function
declaration.
* manual/arith.texi (fesetexcept): Document function.
* math/Versions (fesetexcept): New libm symbol at version
GLIBC_2.25.
* math/Makefile (libm-support): Add fesetexcept.
(tests): Add test-fesetexcept and test-fesetexcept-traps.
* math/test-fesetexcept.c: New file.
* math/test-fesetexcept-traps.c: Likewise.
* sysdeps/nacl/libm.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
Likewise.
* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
Likewise.
* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
It turns out that due to the reduced stack size in tst-tls3 and the
(fixed) default stack cache size, allocated TLS variables are never
freed, so the test coverage for tst-tls3-malloc is less than complete.
This change increases the thread stack size for tst-tls3-malloc only,
to make sure thread stacks and TLS variables are freed.
ISO C allows feraiseexcept to raise "inexact", in addition to the
requested exceptions, when requested to raise "overflow" or
"underflow". Testing on ARM and PowerPC e500 (where glibc's
feraiseexcept has this property) showed that the new test-fexcept test
failed to allow for this; this patch fixes it, by wrapping
feraiseexcept to clear FE_INEXACT if implicitly raised and not raised
before the call. (It would also be possible to do this with
fesetexcept, which always affects exactly the requested flags, but
this patch avoids making this fix depend on the fesetexcept changes.)
Tested for x86_64, x86, arm and e500.
* math/test-fexcept.c (feraiseexcept_exact): New function.
(test_set): Call feraiseexcept_exact instead of feraiseexcept.
(test_except): Likewise.
As shown by the test math/test-fexcept, the powerpc fesetexceptflag
implementation fails to clear a previously set FE_INVALID flag, when
that flag is clear in the saved exceptions and FE_INVALID is included
in the mask of flags to restore, because it fails to mask out the
sub-exceptions of FE_INVALID from the FPSCR state. This patch fixes
the masking logic accordingly.
Tested for powerpc.
[BZ #20455]
* sysdeps/powerpc/fpu/fsetexcptflg.c (__fesetexceptflag): Mask out
all FE_INVALID sub-exceptions from FPSCR when FE_INVALID specified
to be restored.
I noticed that there was no meaningful test coverage for
fegetexceptflag and fesetexceptflag (one test ensures that calls to
them compile and link, but nothing to verify they work correctly).
This patch adds tests for these functions.
fesetexceptflag is meant to set the relevant exception flag bits to
the saved state without causing enabled traps to be taken. On some
architectures, it is not possible to set exception flag bits without
causing enabled traps to occur. Such architectures need to define
EXCEPTION_SET_FORCES_TRAP to 1 in their math-tests.h, as is done in
this patch for powerpc. x86 avoids needing to define this because the
traps resulting from setting exception bits don't occur until the next
floating-point operation or fwait instruction.
Tested for x86_64, x86 and powerpc. Note that test-fexcept fails for
powerpc because of a pre-existing bug in fesetexceptflag for powerpc,
which I'll fix separately.
* math/test-fexcept-traps.c: New file.
* math/test-fexcept.c: Likewise.
* math/Makefile (tests): Add test-fexcept and test-fexcept-traps.
* sysdeps/generic/math-tests.h (EXCEPTION_SET_FORCES_TRAP): New
macro.
* sysdeps/powerpc/math-tests.h [!__NO_FPRS__]
(EXCEPTION_SET_FORCES_TRAP): Likewise.
sparc32 passes floating point values in the integer registers. VIS3
instructions gives access to the movwtos instruction to directly
transfer a value from an integer register to a floating point register.
Therefore it makes sense to provide a VIS3 version consisting in the
generic version compiled with -mvis3.
Changelog:
* math/s_fdim.c: Avoid alias renamed.
* math/s_fdimf.c: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/Makefile
[$(subdir) = math && $(have-as-vis3) = yes] (libm-sysdep_routines):
Add s_fdimf-vis3, s_fdim-vis3.
(CFLAGS-s_fdimf-vis3.c): New. Set to -Wa,-Av9d -mvis3.
(CFLAGS-s_fdim-vis3.c): Likewise.
sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c: New file.
sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c: Likewise.
The fdim and fdimf functions on sparc do not fully follow the standard
and do not set errno to ERANGE when the result overflows. Since glibc
2.24 this causes the two following tests to fail:
Failure: fdim (max_value, -max_value): errno set to 0, expected 34 (ERANGE)
Failure: fdim_upward (max_value, -max_value): errno set to 0, expected 34 (ERANGE)
It happens that using GCC with the generic C code generates very similar
code to the sparc specific implementations. Therefore this patches
remove them. Note it might still worth adding a vis3 specific version of
fdim on sparc32/sparcv9, this is done in a following patch to ease
backporting.
Changelog:
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/Makefile
[$(subdir) = math && $(have-as-vis3) = yes] (libm-sysdep_routines):
Remove s_fdimf-vis3, s_fdim-vis3.
* sysdeps/sparc/sparc32/fpu/s_fdim.S: Delete file.
* sysdeps/sparc/sparc32/fpu/s_fdimf.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf-vis3.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/s_fdim.S: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/s_fdimf.S: Likewise.
* sysdeps/sparc/sparc64/fpu/s_fdim.S: Likewise.
* sysdeps/sparc/sparc64/fpu/s_fdimf.S: Likewise.
When building for sparc32/sparcv9 or sparc64, we assume that VIS
instructions are available and use them in the sparc specific assembly
code. However we do not tell GCC to use such instructions, resulting in
slightly suboptimal code.
Fix that by passing -Wa,-Av9a -mvis to GCC.
Changelog:
* sysdeps/sparc/sparc32/sparcv9/Makefile (sysdep-CFLAGS): Add -mvis.
* sysdeps/sparc/sparc64/Makefile (sysdep-CFLAGS): New. Define to
-Wa,-Av9a -mvis.
When bootstrapping float128, this exposed a number of areas where
the L suffix is incorrectly applied to simple expressions when it
should be applied to each constant in the expression.
In order to stave off more macros in libm-test.inc, apply_lit is
made slightly more intelligent. It will now split expressions
based on space characters, and attempt to apply LIT() to each
token.
Having done this, there are numerous spacing issues within
libm-test.inc which have been fixed.
The above is problematic when the L real suffix is not the most
expressive modifier, and the compiler complains (i.e ppc64) or
silently truncates a value (i.e ppc64).
math.h has a comment about definitions from <bits/mathdef.h>. This
comment is in the wrong place in math.h, far below the inclusion of
<bits/mathdef.h>. It was originally above the inclusion, but the
inclusion was moved by
1998-11-05 Ulrich Drepper <drepper@cygnus.com>
* math/math.h: Unconditionally include bits/mathdef.h. Declare
long double functions only if __NO_LONG_DOUBLE_MATH is not
defined.
[...]
without moving the comment. Furthermore, the comment refers
incorrectly to FLT_EVAL_METHOD and DECIMAL_DIG, which are actually
<float.h> macros, and INFINITY, which is in <bits/inf.h>.
This patch moves the comment back above the include it refers to and
removes the description of macros not defined by the header.
Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).
* math/math.h: Move comment about <bits/mathdef.h> definitions
above inclusion of <bits/mathdef.h>. Do not mention
FLT_EVAL_METHOD, INFINITY or DECIMAL_DIG in that comment.
