http://sourceware.org/ml/libc-alpha/2013-06/msg00919.html
I discovered a number of places where denormals and other corner cases
were being handled wrongly.
- printf_fphex.c: Testing for the low double exponent being zero is
unnecessary. If the difference in exponents is less than 53 then the
high double exponent must be nearing the low end of its range, and the
low double exponent hit rock bottom.
- ldbl2mpn.c: A denormal (ie. exponent of zero) value is treated as
if the exponent was one, so shift mantissa left by one. Code handling
normalisation of the low double mantissa lacked a test for shift count
greater than bits in type being shifted, and lacked anything to handle
the case where the difference in exponents is less than 53 as in
printf_fphex.c.
- math_ldbl.h (ldbl_extract_mantissa): Same as above, but worse, with
code testing for exponent > 1 for some reason, probably a typo for >= 1.
- math_ldbl.h (ldbl_insert_mantissa): Round the high double as per
mpn2ldbl.c (hi is odd or explicit mantissas non-zero) so that the
number we return won't change when applying ldbl_canonicalize().
Add missing overflow checks and normalisation of high mantissa.
Correct misleading comment: "The hidden bit of the lo mantissa is
zero" is not always true as can be seen from the code rounding the hi
mantissa. Also by inspection, lzcount can never be less than zero so
remove that test. Lastly, masking bitfields to their widths can be
left to the compiler.
- mpn2ldbl.c: The overflow checks here on rounding of high double were
just plain wrong. Incrementing the exponent must be accompanied by a
shift right of the mantissa to keep the value unchanged. Above notes
for ldbl_insert_mantissa are also relevant.
[BZ #15680]
* sysdeps/ieee754/ldbl-128ibm/e_rem_pio2l.c: Comment fix.
* sysdeps/ieee754/ldbl-128ibm/printf_fphex.c
(PRINT_FPHEX_LONG_DOUBLE): Tidy code by moving -53 into ediff
calculation. Remove unnecessary test for denormal exponent.
* sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c (__mpn_extract_long_double):
Correct handling of denormals. Avoid undefined shift behaviour.
Correct normalisation of low mantissa when low double is denormal.
* sysdeps/ieee754/ldbl-128ibm/math_ldbl.h
(ldbl_extract_mantissa): Likewise. Comment. Use uint64_t* for hi64.
(ldbl_insert_mantissa): Make both hi64 and lo64 parms uint64_t.
Correct normalisation of low mantissa. Test for overflow of high
mantissa and normalise.
(ldbl_nearbyint): Use more readable constant for two52.
* sysdeps/ieee754/ldbl-128ibm/mpn2ldbl.c
(__mpn_construct_long_double): Fix test for overflow of high
mantissa and correct normalisation. Avoid undefined shift.
http://sourceware.org/ml/libc-alpha/2013-07/msg00001.html
This patch starts the process of supporting powerpc64 little-endian
long double in glibc. IBM long double is an array of two ieee
doubles, so making union ibm_extended_long_double reflect this fact is
the correct way to access fields of the doubles.
* sysdeps/ieee754/ldbl-128ibm/ieee754.h
(union ibm_extended_long_double): Define as an array of ieee754_double.
(IBM_EXTENDED_LONG_DOUBLE_BIAS): Delete.
* sysdeps/ieee754/ldbl-128ibm/printf_fphex.c: Update all references
to ibm_extended_long_double and IBM_EXTENDED_LONG_DOUBLE_BIAS.
* sysdeps/ieee754/ldbl-128ibm/e_exp10l.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/e_expl.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/ldbl2mpn.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/math_ldbl.h: Likewise.
* sysdeps/ieee754/ldbl-128ibm/mpn2ldbl.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/strtold_l.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c: Likewise.
[BZ #15915] As described in the bug, the pattern rule for lib%.so files
in Makerules includes linkobj/libc.so as a dependency. However, the
explicit rule for linkobj/libc.so is in the top-level Makefile.
Thus, the subdirectory makefiles that include Makerules end up with an
erroneous makefile pattern rule for linkobj/libc.so that includes
itself as a dependency. The result is make warnings whenever rules
for other .so files are resolved -- and, on occasion, actual makefile
failures when a race condition causes the implicit rule to actually be
used.
This patch moves the explicit rules for linkobj/libc.so into Makerules
to clear up this problem. It also elaborates a couple of comments
that I'd initially found confusing.
Add support for pointer encryption in glibc internal structures in C
and assembler code. Pointer encryption is a glibc security feature
described here:
https://sourceware.org/glibc/wiki/PointerEncryption
The ARM implementation uses global variables instead of thread pointer
relative accesses to get the value of the pointer encryption guard
because accessing the thread pointer can be very expensive on older
ARM cores.
ports/ChangeLog.arm:
2013-10-03 Will Newton <will.newton@linaro.org>
* sysdeps/arm/__longjmp.S (__longjmp): Demangle fp, sp
and lr when restoring register values.
* sysdeps/arm/include/bits/setjmp.h (JMP_BUF_REGLIST): Remove
sp and lr from list and replace fp with a4.
* sysdeps/arm/jmpbuf-unwind.h (_jmpbuf_sp): New function.
(_JMPBUF_UNWINDS_ADJ): Call _jmpbuf_sp.
* sysdeps/arm/setjmp.S (__sigsetjmp): Mangle fp, sp and lr
before storing register values.
* sysdeps/arm/sysdep.h (LDST_GLOBAL): New macro.
* sysdeps/unix/sysv/linux/arm/sysdep.h (PTR_MANGLE): New macro.
(PTR_DEMANGLE): Likewise. (PTR_MANGLE2): Likewise.
(PTR_DEMANGLE2): Likewise.
Colin Watson reported that some versions of gcc warn about
attribute leaf used on a static function, since it has no
effect on anything but external functions.
* posix/glob.c (next_brace_sub, prefix_array, collated_compare):
Use __THROWNL rather than __THROW on static functions.
Signed-off-by: Eric Blake <eblake@redhat.com>
Fixes BZ #15988.
The check had a typo - it checked for PTHREAD_MUTEX_ROBUST_NP instead
of PTHREAD_MUTEX_ROBUST_NORMAL_NP. It has now been replaced by the
already existing convenience macro USE_REQUEUE_PI.
sysdeps/unix/make-syscalls.sh and sysdeps/unix/Makefile use GNU Bash's
${parameter/pattern/string} parameter expansion. Non-Bash shells (e.g.
dash or BusyBox ash when built with CONFIG_ASH_BASH_COMPAT disabled)
don't support this expansion syntax. So glibc will fail to build when
$(SHELL) expands to a path that isn't provided by Bash.
An example build failure:
for dir in [...]; do \
test -f $dir/syscalls.list && \
{ sysdirs='[...]' \
asm_CPP='gcc -c -I[...] -D_LIBC_REENTRANT -include include/libc-symbols.h -DASSEMBLER -g -Wa,--noexecstack -E -x assembler-with-cpp' \
/bin/sh sysdeps/unix/make-syscalls.sh $dir || exit 1; }; \
test $dir = sysdeps/unix && break; \
done > [build-dir]/sysd-syscallsT
sysdeps/unix/make-syscalls.sh: line 273: syntax error: bad substitution
This patch simply replaces the three instances of the Bash-only syntax
in these files with an echo and sed command substitution.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
This define was removed from the rest of the tree eight years ago.
ports/ChangeLog.arm:
2013-09-24 Will Newton <will.newton@linaro.org>
* ports/sysdeps/arm/nptl/tls.h (TLS_INIT_TP_EXPENSIVE): Remove
macro.
This define was removed from the rest of the tree eight years ago.
ChangeLog:
2013-09-24 Will Newton <will.newton@linaro.org>
* sysdeps/mach/hurd/i386/tls.h (TLS_INIT_TP_EXPENSIVE): Remove
macro.
* sysdeps/mips/math_private.h (libc_feholdexcept_mips): New function.
(libc_feholdexcept): New macro.
(libc_feholdexceptf): New macro.
(libc_feholdexceptl): New macro.
(libc_fesetround_mips): New function.
(libc_fesetround): New macro.
(libc_fesetroundf): New macro.
(libc_fesetroundl): New macro.
(libc_feholdexcept_setround_mips): New function.
(libc_feholdexcept_setround): New macro.
(libc_feholdexcept_setroundf): New macro.
(libc_feholdexcept_setroundl): New macro.
(libc_fesetenv_mips): New function.
(libc_fesetenv): New macro.
(libc_fesetenvf): New macro.
(libc_fesetenvl): New macro.
(libc_feupdateenv_mips): New function.
(libc_feupdateenv): New macro.
(libc_feupdateenvf): New macro.
(libc_feupdateenvl): New macro.
Alan Modra
Joseph Myers
Steve Ellcey
Ondřej Bílka
Brooks Moses
Will Newton
Eric Blake
Chris Metcalf
Richard Henderson
Siddhesh Poyarekar
Petr Machata
Andrew Pinski
Andreas Schwab
Mike Frysinger
Patrick 'P. J.' McDermott
Chris Leonard
Allan McRae
Kaz Kojima
Adhemerval Zanella
Michael Bauer
Olivier Langlois
Roland McGrath
Marcus Shawcroft
Wei-Lun Chao
Maciej W. Rozycki