ia64, s390-64, sparc64 and x86_64 host their own implementation of
sigpending() in corresponding files, but they are identical to generic
linux file despite few comments. This patch removes that files, so the
implementation of sigpending() is taken from sysdeps/unix/sysv/linux
for all ports.
Build-tested on x86_64.
* sysdeps/unix/sysv/linux/ia64/sigpending.c: Remove file.
* sysdeps/unix/sysv/linux/s390/s390-64/sigpending.c: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/sigpending.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sigpending.c: Likewise.
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This is another one where we'll be wanting the base symbols for
powerpc64le rather than just a power7 variant.
* sysdeps/powerpc/powerpc64/multiarch/strncase_l-power7.c: Include
string/strncase_l.c, not string/strncase.c.
(USE_IN_EXTENDED_LOCALE_MODEL): Don't define.
(libc_hidden_def): Redefine.
The routine being assembled here is strcasecmp_l, so ask for that via
__STRCMP and STRCMP defines. That change means tweaking the power7
override. Needed for later powerpc64le changes where we want the base
symbols, not just a power7 variant.
* sysdeps/powerpc/powerpc64/multiarch/strcasecmp_l-power7.S:
(__STRCMP, STRCMP, __strcasecmp_l): Define.
(__strcasecmp): Don't define.
These functions aren't used in ld.so at the moment since we don't have
strcmp or strncmp ifuncs for them there. Remove the ld.so bloat.
* sysdeps/powerpc/powerpc64/multiarch/strcmp-power8.S: Wrap in
IS_IN (libc).
* sysdeps/powerpc/powerpc64/multiarch/strcmp-power9.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/strncmp-power8.S: Likewise.
* sysdeps/powerpc/powerpc64/multiarch/strncmp-power9.S: Likewise.
USE_AS_STPNCPY is defined by sysdeps/powerpc/powerpc64/power8/stpncpy.S,
included by this file.
* sysdeps/powerpc/powerpc64/multiarch/stpncpy-power8.S: Don't define
USE_AS_STPNCPY.
It seems to me that libc.a should not contain any of the __GI_
symbols, and certainly --enable-multi-arch ought to not add to the
list. At the end of this patch series we have the following in both
--enable-multi-arch and --disable-multi-arch libc.a:
0000000000000000 T __GI___readdir64
0000000000000000 T __GI___fxstatat64
0000000000000000 T __GI_getrlimit
0000000000000000 T __GI___getrlimit
* sysdeps/powerpc/powerpc64/fpu/multiarch/s_isnan-ppc64.S (hidden_def):
Redefine only when SHARED.
i586 strcpy.S used a clever trick with LEA to implement jump table:
/* ECX has the last 2 bits of the address of source - 1. */
andl $3, %ecx
call 2f
2: popl %edx
/* 0xb is the distance between 2: and 1:. */
leal 0xb(%edx,%ecx,8), %ecx
jmp *%ecx
.align 8
1: /* ECX == 0 */
orb (%esi), %al
jz L(end)
stosb
xorl %eax, %eax
incl %esi
/* ECX == 1 */
orb (%esi), %al
jz L(end)
stosb
xorl %eax, %eax
incl %esi
/* ECX == 2 */
orb (%esi), %al
jz L(end)
stosb
xorl %eax, %eax
incl %esi
/* ECX == 3 */
L(1): movl (%esi), %ecx
leal 4(%esi),%esi
This fails if there are instruction length changes before L(1):. This
patch replaces it with conditional branches:
cmpb $2, %cl
je L(Src2)
ja L(Src3)
cmpb $1, %cl
je L(Src1)
L(Src0):
which have similar performance and work with any instruction lengths.
Tested on i586 and i686 with and without --disable-multi-arch.
[BZ #22353]
* sysdeps/i386/i586/strcpy.S (STRCPY): Use conditional branches.
(1): Renamed to ...
(L(Src0)): This.
(L(Src1)): New.
(L(Src2)): Likewise.
(L(1)): Renamed to ...
(L(Src3)): This.
POWER9 DD2.1 and earlier has an issue where some cache inhibited
vector load traps to the kernel, causing a performance degradation. To
handle this in memcpy and memmove, lvx/stvx is used for aligned
addresses instead of lxvd2x/stxvd2x.
Reference: https://patchwork.ozlabs.org/patch/814059/
* sysdeps/powerpc/powerpc64/power7/memcpy.S: Replace
lxvd2x/stxvd2x with lvx/stvx.
* sysdeps/powerpc/powerpc64/power7/memmove.S: Likewise.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The glibc implementation of iseqsig relies on ordered comparison
operators raising the "invalid" exception for quiet NaN operands, with
a workaround on platforms where a GCC bug means that exception is not
raised. For x86, that bug has now been fixed for GCC 8, so this patch
disables the workaround in that case. If and when the corresponding
bugs for powerpc and s390 are fixed, the headers for those platforms
should of course be updated similarly.
Tested for x86_64 and x86, including with GCC mainline. Note that
other failures appear with GCC mainline because of spurious use of
ordered comparison instructions for unordered operations
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82692>.
* sysdeps/x86/fpu/fix-fp-int-compare-invalid.h
(FIX_COMPARE_INVALID): Define to 0 if [__GNUC_PREREQ (8, 0)].
As shown in some buildbot issues on aarch64 and powerpc, calling
clone (VFORK) and waitpid (WNOHANG) does not guarantee the child
is ready to be collected. This patch changes the call back to 0
as before fe05e1cb6d fix.
This change can lead to the scenario 4.3 described in the commit,
where the waitpid call can hang undefinitely on the call. However
this is also a very unlikely and also undefinied situation where
both the caller is trying to terminate a pid before posix_spawn
returns and the race pid reuse is triggered. I don't see how to
correct handle this specific situation within posix_spawn.
Checked on x86_64-linux-gnu, aarch64-linux-gnu and
powerpc64-linux-gnu.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Use 0 instead of
WNOHANG in waitpid call.
cfi info for stack adjust needs to be on the insn doing the adjust.
cfi describing register saves can be anywhere after the save insn but
before the reg is altered. Fewer locations with cfi result in smaller
cfi programs and possibly slightly faster exception handling. Thus
the LR cfi_offset move.
The idea behind ajusting sp after restoring regs is to break a
register dependency chain, in this case not be using r1 immediately
after it is modified.
The missing LR cfi_restore meant that code after the blr,
unaligned_lt_16 and other labels, would have cfi that said LR was at
cfa+16, but that code is reached without LR being saved.
* sysdeps/powerpc/powerpc64/power8/strncpy.S: Move LR cfi.
Adjust stack after restoring regs. Add missing LR cfi_restore.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
This patch moves the frame setup and teardown to immediately around
the single memset call, as has been done for power8. I've also
decreased FRAMESIZE to that needed to save the two callee-saved
registers used. Plus added cfi.
* sysdeps/powerpc/powerpc64/power7/strncpy.S: Decrease FRAMESIZE.
Move LR save and frame setup/teardown and LR restore to
immediately around memset call. Provide cfi.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
This patch replaces i386 assembly versions of e_exp2f with generic
e_exp2f.c. For workload-spec2017.wrf, on Nehalem, it improves
performance by:
Before After Improvement
reciprocal-throughput 112.996 40.0454 182%
latency 126.581 54.4479 132%
On Skylake, it improves performance by:
Before After Improvement
reciprocal-throughput 113.14 39.447 186%
latency 136.068 55.684 144%
On IvyBridge with --disable-multi-arch, it improves performance by:
Before After Improvement
reciprocal-throughput 132.521 40.3759 228%
latency 145.791 58.4587 149%
* sysdeps/i386/fpu/e_exp2f.S: Removed.
* sysdeps/i386/fpu/w_exp2f.c: Likewise.
* sysdeps/i386/fpu/libm-test-ulps: Updated for generic e_exp2f.c.
* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Likewise.
* sysdeps/i386/i686/fpu/multiarch/Makefile (libm-sysdep_routines):
Add e_exp2f-sse2.
(CFLAGS-e_exp2f-sse2.c): New.
* sysdeps/i386/i686/fpu/multiarch/e_exp2f-sse2.c: New file.
* sysdeps/i386/i686/fpu/multiarch/e_exp2f.c: Likewise.
The bits/floatn.h header currently only has defines relating to
_Float128. This patch adds defines relating to other _FloatN /
_FloatNx types.
The approach taken is to add defines for all _FloatN / _FloatNx types
known to GCC, and to put them in a common bits/floatn-common.h header
included at the end of all the individual bits/floatn.h headers. If
in future some defines become different for different glibc
configurations, they will move out into the separate bits/floatn.h
headers.
Some defines are expected always to be the same across glibc ports.
Corresponding defines are nevertheless put in this header. The intent
is that where there are conditionals (in headers or in non-installed
files) that can just repeat the same or nearly the same logic for each
floating-point type, they should do so, even if in fact the cases for
some types could be unconditionally present or absent because the same
conditionals are true or false for all glibc configurations. This
should make the glibc code with such conditionals easier to read,
because the reader can just see that the same conditionals are
repeated for each type, rather than seeing different conditionals for
different types and needing to reason, at each location with such
differences, why those differences are indeed correct there. (Cases
involving per-format rather than per-type logic are more likely still
to need differences in how they handle different types.)
Having such defines and conditionals also helps in incremental
preparation for adding _Float32 / _Float64 / _Float32x / _Float64x
function aliases. I intend subsequent patches to add such
conditionals corresponding to those already present for _Float128, as
well as making more architecture-specific function implementations use
common macros to define aliases in preparation for adding such _FloatN
/ _FloatNx aliases.
Tested for x86_64.
* bits/floatn-common.h: New file.
* math/Makefile (headers): Add bits/floatn-common.h.
* bits/floatn.h: Include <bits/floatn-common.h>.
* sysdeps/ia64/bits/floatn.h: Likewise.
* sysdeps/ieee754/ldbl-128/bits/floatn.h: Likewise.
* sysdeps/mips/ieee754/bits/floatn.h: Likewise.
* sysdeps/powerpc/bits/floatn.h: Likewise.
* sysdeps/x86/bits/floatn.h: Likewise.
As noted by Florian Weimer, current Linux posix_spawn implementation
can trigger an assert if the auxiliary process is terminated before
actually setting the err member:
340 /* Child must set args.err to something non-negative - we rely on
341 the parent and child sharing VM. */
342 args.err = -1;
[...]
362 new_pid = CLONE (__spawni_child, STACK (stack, stack_size), stack_size,
363 CLONE_VM | CLONE_VFORK | SIGCHLD, &args);
364
365 if (new_pid > 0)
366 {
367 ec = args.err;
368 assert (ec >= 0);
Another possible issue is killing the child between setting the err and
actually calling execve. In this case the process will not ran, but
posix_spawn also will not report any error:
269
270 args->err = 0;
271 args->exec (args->file, args->argv, args->envp);
As suggested by Andreas Schwab, this patch removes the faulty assert
and also handles any signal that happens before fork and execve as the
spawn was successful (and thus relaying the handling to the caller to
figure this out). Different than Florian, I can not see why using
atomics to set err would help here, essentially the code runs
sequentially (due CLONE_VFORK) and I think it would not be legal the
compiler evaluate ec without checking for new_pid result (thus there
is no need to compiler barrier).
Summarizing the possible scenarios on posix_spawn execution, we
have:
1. For default case with a success execution, args.err will be 0, pid
will not be collected and it will be reported to caller.
2. For default failure case, args.err will be positive and the it will
be collected by the waitpid. An error will be reported to the
caller.
3. For the unlikely case where the process was terminated and not
collected by a caller signal handler, it will be reported as succeful
execution and not be collected by posix_spawn (since args.err will
be 0). The caller will need to actually handle this case.
4. For the unlikely case where the process was terminated and collected
by caller we have 3 other possible scenarios:
4.1. The auxiliary process was terminated with args.err equal to 0:
it will handled as 1. (so it does not matter if we hit the pid
reuse race since we won't possible collect an unexpected
process).
4.2. The auxiliary process was terminated after execve (due a failure
in calling it) and before setting args.err to -1: it will also
be handle as 1. but with the issue of not be able to report the
caller a possible execve failures.
4.3. The auxiliary process was terminated after args.err is set to -1:
this is the case where it will be possible to hit the pid reuse
case where we will need to collected the auxiliary pid but we
can not be sure if it will be expected one. I think for this
case we need to actually change waitpid to use WNOHANG to avoid
hanging indefinitely on the call and report an error to caller
since we can't differentiate between a default failure as 2.
and a possible pid reuse race issue.
Checked on x86_64-linux-gnu.
* sysdeps/unix/sysv/linux/spawni.c (__spawnix): Handle the case where
the auxiliary process is terminated by a signal before calling _exit
or execve.
In _dl_runtime_resolve, use fxsave/xsave/xsavec to preserve all vector,
mask and bound registers. It simplifies _dl_runtime_resolve and supports
different calling conventions. ld.so code size is reduced by more than
1 KB. However, use fxsave/xsave/xsavec takes a little bit more cycles
than saving and restoring vector and bound registers individually.
Latency for _dl_runtime_resolve to lookup the function, foo, from one
shared library plus libc.so:
Before After Change
Westmere (SSE)/fxsave 345 866 151%
IvyBridge (AVX)/xsave 420 643 53%
Haswell (AVX)/xsave 713 1252 75%
Skylake (AVX+MPX)/xsavec 559 719 28%
Skylake (AVX512+MPX)/xsavec 145 272 87%
Ryzen (AVX)/xsavec 280 553 97%
This is the worst case where portion of time spent for saving and
restoring registers is bigger than majority of cases. With smaller
_dl_runtime_resolve code size, overall performance impact is negligible.
On IvyBridge, differences in build and test time of binutils with lazy
binding GCC and binutils are noises. On Westmere, differences in
bootstrap and "makc check" time of GCC 7 with lazy binding GCC and
binutils are also noises.
[BZ #21265]
* sysdeps/x86/cpu-features-offsets.sym (XSAVE_STATE_SIZE_OFFSET):
New.
* sysdeps/x86/cpu-features.c: Include <libc-pointer-arith.h>.
(get_common_indeces): Set xsave_state_size, xsave_state_full_size
and bit_arch_XSAVEC_Usable if needed.
(init_cpu_features): Remove bit_arch_Use_dl_runtime_resolve_slow
and bit_arch_Use_dl_runtime_resolve_opt.
* sysdeps/x86/cpu-features.h (bit_arch_Use_dl_runtime_resolve_opt):
Removed.
(bit_arch_Use_dl_runtime_resolve_slow): Likewise.
(bit_arch_Prefer_No_AVX512): Updated.
(bit_arch_MathVec_Prefer_No_AVX512): Likewise.
(bit_arch_XSAVEC_Usable): New.
(STATE_SAVE_OFFSET): Likewise.
(STATE_SAVE_MASK): Likewise.
[__ASSEMBLER__]: Include <cpu-features-offsets.h>.
(cpu_features): Add xsave_state_size and xsave_state_full_size.
(index_arch_Use_dl_runtime_resolve_opt): Removed.
(index_arch_Use_dl_runtime_resolve_slow): Likewise.
(index_arch_XSAVEC_Usable): New.
* sysdeps/x86/cpu-tunables.c (TUNABLE_CALLBACK (set_hwcaps)):
Support XSAVEC_Usable. Remove Use_dl_runtime_resolve_slow.
* sysdeps/x86_64/Makefile (tst-x86_64-1-ENV): New if tunables
is enabled.
* sysdeps/x86_64/dl-machine.h (elf_machine_runtime_setup):
Replace _dl_runtime_resolve_sse, _dl_runtime_resolve_avx,
_dl_runtime_resolve_avx_slow, _dl_runtime_resolve_avx_opt,
_dl_runtime_resolve_avx512 and _dl_runtime_resolve_avx512_opt
with _dl_runtime_resolve_fxsave, _dl_runtime_resolve_xsave and
_dl_runtime_resolve_xsavec.
* sysdeps/x86_64/dl-trampoline.S (DL_RUNTIME_UNALIGNED_VEC_SIZE):
Removed.
(DL_RUNTIME_RESOLVE_REALIGN_STACK): Check STATE_SAVE_ALIGNMENT
instead of VEC_SIZE.
(REGISTER_SAVE_BND0): Removed.
(REGISTER_SAVE_BND1): Likewise.
(REGISTER_SAVE_BND3): Likewise.
(REGISTER_SAVE_RAX): Always defined to 0.
(VMOV): Removed.
(_dl_runtime_resolve_avx): Likewise.
(_dl_runtime_resolve_avx_slow): Likewise.
(_dl_runtime_resolve_avx_opt): Likewise.
(_dl_runtime_resolve_avx512): Likewise.
(_dl_runtime_resolve_avx512_opt): Likewise.
(_dl_runtime_resolve_sse): Likewise.
(_dl_runtime_resolve_sse_vex): Likewise.
(USE_FXSAVE): New.
(_dl_runtime_resolve_fxsave): Likewise.
(USE_XSAVE): Likewise.
(_dl_runtime_resolve_xsave): Likewise.
(USE_XSAVEC): Likewise.
(_dl_runtime_resolve_xsavec): Likewise.
* sysdeps/x86_64/dl-trampoline.h (_dl_runtime_resolve_avx512):
Removed.
(_dl_runtime_resolve_avx512_opt): Likewise.
(_dl_runtime_resolve_avx): Likewise.
(_dl_runtime_resolve_avx_opt): Likewise.
(_dl_runtime_resolve_sse): Likewise.
(_dl_runtime_resolve_sse_vex): Likewise.
(_dl_runtime_resolve_fxsave): New.
(_dl_runtime_resolve_xsave): Likewise.
(_dl_runtime_resolve_xsavec): Likewise.
When --enable-static-pie is used to configure glibc, we need to use
_dl_relocate_static_pie to compute load address in static PIE.
* sysdeps/m68k/dl-machine.h (elf_machine_load_address): Use
_dl_relocate_static_pie instead of _dl_start to compute load
address in static PIE.
After commit 37f802f864 (Remove
__need_IOV_MAX and __need_FOPEN_MAX), UIO_MAXIOV is no longer supplied
(indirectly) through <bits/stdio_lim.h>, so sysdeps/posix/sysconf.c no
longer sees the definition.
This patch adds a MIPS-specific bits/floatn.h header. This header is
identical to the ldbl-128 version except for the comment at the top;
the purpose is to ensure that a 32-bit MIPS build installs a header
that is the same as in a 64-bit MIPS build and so properly shows
_Float128 support to be available for 64-bit compilations, on the
general principle of an installation for one multilib providing
headers also suitable for other multilibs.
Tested with build-many-glibcs.py.
* sysdeps/mips/ieee754/bits/floatn.h: New file.
Similar to bug 21987 for SPARC, MIPS64 wrongly installs the ldbl-128
version of bits/long-double.h, meaning incorrect results when using
headers installed from a 64-bit installation for a 32-bit build. (I
haven't actually seen this cause build failures before its interaction
with bits/floatn.h did so - installed headers wrongly expecting
_Float128 to be available in a 32-bit configuration.)
This patch fixes the bug by moving the MIPS header to
sysdeps/mips/ieee754, which comes before sysdeps/ieee754/ldbl-128 in
the sysdeps directory ordering. (bits/floatn.h will need a similar
fix - duplicating the ldbl-128 version for MIPS will suffice - for
headers from a 32-bit installation to be correct for 64-bit builds.)
Tested with build-many-glibcs.py (compilers build for
mips64-linux-gnu, where there was previously a libstdc++ build failure
as at
<https://sourceware.org/ml/libc-testresults/2017-q4/msg00130.html>).
[BZ #22322]
* sysdeps/mips/bits/long-double.h: Move to ....
* sysdeps/mips/ieee754/bits/long-double.h: ... here.
This patch adds support for *f128 function aliases on platforms where
long double has the binary128 format (and thus GCC 7 provides the
_Float128 type with the same ABI as long double but as a distinct type
in terms of C type compatibility). This is the same API as provided
in glibc 2.26 for powerpc64le / x86_64 / x86 / ia64 where _Float128
has a different format from long double, with the bulk of the API
coming from TS 18661-3. All the functions alias the corresponding
long double functions, and __* function names are not provided since
those are only needed once for each floating-point format, not more
than once for different types with the same format (so for example,
-ffinite-math-only maps foof128 to __fool_finite, while type-generic
macros end up calling e.g. __issignalingl for _Float128 arguments on
such platforms).
The preparation for this feature was done in previous patches, so this
one just needs to add the relevant makefile and header definitions,
and update macro definitions of libm_alias_ldouble_other_r, to turn on
the feature, and update documentation and ABI baselines.
Tested (a) for x86_64, (b) for aarch64, (c) with build-many-glibcs.py
with both GCC 6 and GCC 7.
* sysdeps/ieee754/ldbl-128/Makeconfig: New file.
* sysdeps/ieee754/ldbl-128/bits/floatn.h: Likewise.
* sysdeps/ieee754/ldbl-128/float128-abi.h: Likewise.
* sysdeps/generic/libm-alias-ldouble.h: Include <bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128]
(libm_alias_ldouble_other_r): Also create _Float128 alias.
* sysdeps/ieee754/ldbl-opt/libm-alias-ldouble.h: Include
<bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128]
(libm_alias_ldouble_other_r): Also create _Float128 alias.
* manual/math.texi (Mathematics): Document additional architecture
support for _Float128.
* sysdeps/unix/sysv/linux/aarch64/libc.abilist: Update.
* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist: Likewise.
* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
This patch rewrites aarch64 elf_machine_load_address to use special _DYNAMIC
symbol instead of _dl_start.
The static address of _DYNAMIC symbol is stored in the first GOT entry.
Here is the change which makes this solution work (part of binutils 2.24):
https://sourceware.org/ml/binutils/2013-06/msg00248.html
i386, x86_64 targets use the same method to do this as well.
The original implementation relies on a trick that R_AARCH64_ABS32 relocation
being resolved at link time and the static address fits in the 32bits.
However, in LP64, normally, the address is defined to be 64 bit.
Here is the C version one which should be portable in all cases.
* sysdeps/aarch64/dl-machine.h (elf_machine_load_address): Use
_DYNAMIC symbol to calculate load address.
A performance regression was introduced by commit
84d74e427a "powerpc: Cleanup fenv_private.h".
In the powerpc implementation of SET_RESTORE_ROUND, there is the
following code in the "SET" function (slightly simplified):
--
old.fenv = fegetenv_register ();
new.l = (old.l & _FPU_MASK_TRAPS_RN) | r; (1)
if (new.l != old.l) (2)
{
if ((old.l & _FPU_ALL_TRAPS) != 0)
(void) __fe_mask_env ();
fesetenv_register (new.fenv); (3)
--
Line (1) sets the value of "new" to the current value of FPSCR,
but masks off summary bits, exceptions, non-IEEE mode, and
rounding mode, then ORs in the new rounding mode.
Line (2) compares this new value to the current value in order to
avoid setting a new value in the FPSCR (line (3)) unless something
significant has changed (exception enables or rounding mode).
The summary bits are not germane to the comparison, but are cleared
in "new" and preserved in "old", resulting in false negative
comparisons, and unnecessarily setting the FPSCR in those cases
with associated negative performance impacts.
The solution is to treat the summaries identically for "new" and "old":
- save them in SET
- leave them alone otherwise
- restore the saved values in RESTORE
Also minor changes:
- expand _FPU_MASK_RN to 64bit hex, to match other MASKs
- treat bit 52 (left-to-right) as reserved (since it is)
* sysdeps/powerpc/fpu/fenv_private.h (_FPU_MASK_TRAPS_RN):
(_FPU_MASK_FRAC_INEX_RET_CC): Fix masks to more properly handle
summary bits.
(_FPU_MASK_RN): Expand _FPU_MASK_RN to 64bit hex.
(_FPU_MASK_NOT_RN_NI): Treat bit 52 (left-to-right) as reserved.
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.vnet.ibm.com>
This patch moves the generic definition from x86_64 init-arch
to a common header ifunc-init.h. No functional changes is expected.
Checked on a x86_64-linux-gnu build.
* sysdeps/generic/ifunc-init.h: New file.
* sysdeps/x86/init-arch.h: Use generic ifunc-init.h.
With support for _Float128 functions on platforms where that type has
the same ABI as long double, as well as on platforms where it is
ABI-distinct, those functions will need to be exported from glibc's
shared libraries at appropriate symbol versions in each case.
This patch avoids duplication of lists of symbols to export by moving
the symbols other than __* to math/Versions and stdlib/Versions.
There, they are conditional on <float128-abi.h> defining
FLOAT128_VERSION and a default version of that header is added that
does not define that macro. Enabling the float128 function aliases
will then include adding a sysdeps/ieee754/ldbl-128/float128-abi.h
that defines FLOAT128_VERSION to GLIBC_2.27. Symbols __* remain in
sysdeps/ieee754/float128/Versions; those symbols should be present
only once per floating-point format, not once per type.
Note that if any platforms currently lacking support for a type with
binary128 format get glibc support for such a type in future (whether
only as _Float128, or also as a new long double format), and new libm
functions (present for all types) have been added by then, additional
macros will be needed to allow such functions to get a version of the
form "GLIBC_2.28 if the platform had _Float128 support by then, or the
later version at which that platform had _Float128 support added".
This is not however a preexisting condition, but would have applied
equally to the existing support for _Float128 as an ABI-distinct
type. New all-type libm functions should just be added to the
appropriate symbol version (currently GLIBC_2.27) for all types, with
such special-case handling for _Float128 versions (and _Float64x as
well in future) waiting until someone actually wants to add support
for _Float128 to an existing platform after a release in which that
platform and a post-2.26 libm function had support but that platform
lacked _Float128 support.
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by this patch. Also tested in conjunction
with the remaining changes to enable float128 aliases.
* sysdeps/generic/float128-abi.h: New file.
* sysdeps/ieee754/float128/Versions (FLOAT128_VERSION): Move
non-__prefixed symbols to ....
* math/Versions: ... here. Include <float128-abi.h>.
* stdlib/Versions ... and here. Include <float128-abi.h>
This patch adds support for building strtof128, wcstof128, strtof128_l
and wcstof128_l as aliases, in the case of __HAVE_FLOAT128 &&
!__HAVE_DISTINCT_FLOAT128.
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by this patch. Also tested together with
changes to enable float128 aliases.
* stdlib/strtold.c: Include <bits/floatn.h>
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128] (strtof128): Define
and later undefine as macro. Define as weak alias if
[!USE_WIDE_CHAR].
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128] (wcstof128): Define
and later undefine as macro. Define as weak alias if
[USE_WIDE_CHAR].
* sysdeps/ieee754/ldbl-128/strtold_l.c [__HAVE_FLOAT128 &&
!__HAVE_DISTINCT_FLOAT128] (strtof128_l): Define and later
undefine as macro. Define as weak alias if [!USE_WIDE_CHAR].
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128] (wcstof128_l):
Define and later undefine as macro. Define as weak alias if
[USE_WIDE_CHAR].
* sysdeps/ieee754/ldbl-64-128/strtold_l.c: Include
<bits/floatn.h>.
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128] (strtof128_l):
Define and later undefine as macro. Define as weak alias if
[!USE_WIDE_CHAR].
[__HAVE_FLOAT128 && !__HAVE_DISTINCT_FLOAT128] (wcstof128_l):
Define and later undefine as macro. Define as weak alias if
[USE_WIDE_CHAR].
This patch makes ldbl-64-128/s_nextafterl.c restore the default
weak_alias definition and use libm_alias_ldouble_other (having
undefined and redefined weak_alias for the include of
ldbl-128/s_nextafterl.c, so the libm_alias_ldouble use in the latter
file is ineffective).
Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by this patch. Also tested together with
changes to enable float128 aliases.
* sysdeps/ieee754/ldbl-64-128/s_nextafterl.c (weak_alias):
Undefine and restore default definition. Use
libm_alias_ldouble_other.
Normally, TLS relocations against local symbols are optimised by the linker
to be absolute. However, gold does not do this, and so it is possible to
end up with, for example, R_SPARC_TLS_DTPMOD64 referring to a local symbol.
Since sym_map is left as null in elf_machine_rela for the special local
symbol case, the relocation handling thinks it has nothing to do, and so
the module gets left as 0. Havoc then ensues when the variable in question
is accessed.
Before this fix, the main_local_gold program would receive a SIGBUS on
sparc64, and SIGSEGV on powerpc32. With this fix applied, that test now
passes like the rest of them.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela):
Assign sym_map to be map for local symbols, as TLS relocations
use sym_map to determine whether the symbol is defined and to
extract the TLS information.
* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela): Likewise.
Fix the ifdef clause that was being used in the opposite way, setting
a wrong value of the carry bit.
This is also correcting 2 memory accesses that were mistakenly referring
to r0 while they were supposed to mean the immediate value 0.
[BZ #22142]
* stdio-common/tst-printf.c (fp_test): Add tests for DBL_MAX and
-DBL_MAX.
(do_test): Likewise.
* stdio-common/tst-printf.sh: Likewise.
* sysdeps/powerpc/powerpc64/power7/add_n.S: Invert the initial
ifdef clause in order to set the carry bit right. Replace r0 by
0 without changing the behavior.
