Commit Graph

133 Commits

Author SHA1 Message Date
Paul Eggert
581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00
Siddhesh Poyarekar
30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30
liuhongt
6ec6c77867 soft-fp: Add __extendhfsf2/__extendhfdf2, __truncsfhf2/__truncdfhf2, __eqhf2/__nehf2
1. Add __extendhfdf2/__extendhfsf2 to return an IEEE half converted to IEEE double/single.
2. Add __truncdfhf2/__extendsfhf2 to truncate IEEE double/single into IEEE half.
3. Add __eqhf2/__nehf2 to return 0 if a == b and a,b are not NAN, otherwise return 1.

These are needed by x86 _Float16:

https://software.intel.com/content/www/us/en/develop/download/intel-avx512-fp16-architecture-specification.html

support in GCC.
2021-07-07 08:01:32 -07:00
H.J. Lu
8241409e29 soft-fp: Add __extendhfxf2 and __truncxfhf2
1. Add __extendhfxf2 to return an IEEE half converted to IEEE extended.
2. Add __truncxfhf2 to truncate IEEE extended into IEEE half.

These are needed by x86 _Float16:

https://software.intel.com/content/www/us/en/develop/download/intel-avx512-fp16-architecture-specification.html

support in GCC.
2021-07-01 11:02:58 -07:00
Paul Eggert
2b778ceb40 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
2021-01-02 12:17:34 -08:00
Joseph Myers
d614a75396 Update copyright dates with scripts/update-copyrights. 2020-01-01 00:14:33 +00:00
Paul Eggert
5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 02:43:31 -07:00
Paul Eggert
ab74d59f65 Correct the spelling of more contributors
Correct the spellings of Rafael Ávila de Espíndola,
Uroš Bizjak, Alexandra Hájková, and Rafał Lużyński.
2019-08-29 02:50:04 -07:00
H.J. Lu
69da3c9e87 soft-fp: Properly check _FP_W_TYPE_SIZE [BZ #24066]
quad.h have

 #if _FP_W_TYPE_SIZE < 64

union _FP_UNION_Q
{
  Use 4 _FP_W_TYPEs
}

 #else

union _FP_UNION_Q
{
  Use 2 _FP_W_TYPEs
}

 #endif

Replace

 #if (2 * _FP_W_TYPE_SIZE) < _FP_FRACBITS_Q

with

 #if _FP_W_TYPE_SIZE < 64

to check whether 4 or 2 _FP_W_TYPEs are used for IEEE quad precision.
Tested with build-many-glibcs.py.

	[BZ #24066]
	* soft-fp/extenddftf2.c: Use "_FP_W_TYPE_SIZE < 64" to check if
	4_FP_W_TYPEs are used for IEEE quad precision.
	* soft-fp/extendhftf2.c: Likewise.
	* soft-fp/extendsftf2.c: Likewise.
	* soft-fp/extendxftf2.c: Likewise.
	* soft-fp/trunctfdf2.c: Likewise.
	* soft-fp/trunctfhf2.c: Likewise.
	* soft-fp/trunctfsf2.c: Likewise.
	* soft-fp/trunctfxf2.c: Likewise.
	* sysdeps/alpha/ots_cvttx.c: Likewise.
	* sysdeps/alpha/ots_cvtxt.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_daddl.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_ddivl.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_dmull.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_dsubl.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_faddl.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_fdivl.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_fmull.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_fsubl.c: Likewise.
	* sysdeps/sparc/sparc32/q_dtoq.c: Likewise.
	* sysdeps/sparc/sparc32/q_qtod.c: Likewise.
	* sysdeps/sparc/sparc32/q_qtos.c: Likewise.
	* sysdeps/sparc/sparc32/q_stoq.c: Likewise.
	* sysdeps/sparc/sparc64/qp_dtoq.c: Likewise.
	* sysdeps/sparc/sparc64/qp_qtod.c: Likewise.
	* sysdeps/sparc/sparc64/qp_qtos.c: Likewise.
	* sysdeps/sparc/sparc64/qp_stoq.c: Likewise.
2019-01-07 09:04:39 -08:00
Joseph Myers
04277e02d7 Update copyright dates with scripts/update-copyrights.
* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.
2019-01-01 00:11:28 +00:00
Zong Li
af1d5782c1 soft-fp: Add implementation for 128 bit self-contained
Here only add the implementation when building the RV32 port.

These macros are used when the following situations occur at the same
time: soft-fp fma, ldbl-128 and 32-bit _FP_W_TYPE_SIZE. The RISC-V
32-bit port is the first port which use all three together.

This is the building flow about the situation:
When building soft-fp/s_fmal.c, there uses the FP_FMA_Q in __fmal.
The _FP_W_TYPE_SIZE is defined to 32-bit in sysdeps/riscv/sfp-machine.h,
so the FP_FMA_Q was defined to _FP_FMA (Q, 4, 8, R, X, Y, Z) in
soft-fp/quad.h.

Something in the soft-fp/quad.h:
 #if _FP_W_TYPE_SIZE < 64
    # define FP_FMA_Q(R, X, Y, Z)    _FP_FMA (Q, 4, 8, R, X, Y, Z)
 #else
    # define FP_FMA_Q(R, X, Y, Z)    _FP_FMA (Q, 2, 4, R, X, Y, Z)
 #endif

Finally, in _FP_FMA (fs, wc, dwc, R, X, Y, Z), it will use the
_FP_FRAC_HIGHBIT_DW_##dwc macro, and it will be expanded to
_FP_FRAC_HIGHBIT_DW_8, but the _FP_FRAC_HIGHBIT_DW_8 is not be
implemented in soft-fp/op-8.h. there is only _FP_FRAC_HIGHBIT_DW_1,
_FP_FRAC_HIGHBIT_DW_2 and _FP_FRAC_HIGHBIT_DW_4 in the
soft-fp/op-*.h.

After this modification, we can pass the soft floating testing of glibc
testsuites on RV32.

	* soft-fp/op-8.h (_FP_FRAC_SET_8, _FP_FRAC_ADD_8, _FP_FRAC_SUB_8)
	(_FP_FRAC_CLZ_8, _FP_MINFRAC_8, _FP_FRAC_NEGP_8, _FP_FRAC_ZEROP_8)
	(_FP_FRAC_HIGHBIT_DW_8, _FP_FRAC_COPY_4_8, _FP_FRAC_COPY_8_4)
	(__FP_FRAC_SET_8): Add implementation for RV32 use.
2018-11-01 18:22:00 +00:00
Zong Li
ff48ea6787 soft-fp: Use temporary variable in FP_FRAC_SUB_3/FP_FRAC_SUB_4
In FRAC_SUB_3(R, X, Y) and FRAC_SUB_4(R,, X, Y), it reference both
the X[N] and X[N] after R[N] have been set. If one of the X and Y is
the same address with R, the result of the calculation is wrong,
because the value of the original X and Y are overwritten.

In glibc, there are two places use FRAC_SUB and occurs the overlap.
The first is _FP_DIV_MEAT_N_loop in op-common.h, it uses the source
_FP_DIV_MEAT_N_loop_u as the destination. This macro only be used
when N is one(_FP_DIV_MEAT_1_loop) and then the _FP_FRAC_SUB_##wc
extend to _FP_FRAC_SUB_1 in this macro. so it also work because
_FP_FRAC_SUB_1 has no overlap problem in its implementation.
The second places is _FP_DIV_MEAT_4_udiv, the original value of X##_f[0]
is overwritten before the calculatation.

In FRAC_SUB_1 and FRAC_SUB_2, there don't refer the source after
destination have been set, so they have no problem.

After this modification, we can pass the soft floating testing of glibc
testsuites on RV32.

	* soft-fp/op-4.h (_FP_FRAC_SUB_3, _FP_FRAC_SUB_4): Use temporary
	variable to avoid overlap arguments.
2018-11-01 17:34:39 +00:00
Joseph Myers
0d2163ebf2 Make powerpc-nofpu __sqrtsf2, __sqrtdf2 compat symbols (bug 18473).
powerpc-nofpu libc exports __sqrtsf2 and __sqrtdf2 symbols.  The
export of these soft-fp symbols is a mistake; they aren't part of the
libgcc interface and GCC will never generate code that calls them.
This patch makes them into compat symbols (no code built for static
libc), moving their sources from the generic soft-fp sources to
sysdeps/powerpc/nofpu (the underlying soft-fp FP_SQRT functionality
remains of use to implement actual sqrt public interfaces, such as
sqrtl / sqrtf128 for which it is used on various platforms, but
__sqrt[sdt]f2 are not such interfaces).

Tested with build-many-glibcs.py for relevant platforms.

	[BZ #18473]
	* soft-fp/sqrttf2.c: Remove file.
	* soft-fp/sqrtdf2.c: Move to ....
	* sysdeps/powerpc/nofpu/sqrtdf2.c: ... here.  Include
	<shlib-compat.h>.
	(__sqrtdf2): Make conditional on
	[SHLIB_COMPAT (libc, GLIBC_2_3_2, GLIBC_2_28)].  Define as compat
	symbol.
	* soft-fp/sqrtsf2.c: Move to ....
	* sysdeps/powerpc/nofpu/sqrtsf2.c: ... here.  Include
	<shlib-compat.h>.
	(__sqrtsf2): Make conditional on
	[SHLIB_COMPAT (libc, GLIBC_2_3_2, GLIBC_2_28)].  Define as compat
	symbol.
	* soft-fp/Makefile (gcc-single-routines): Remove sqrtsf2.
	(gcc-double-routines): Remove sqrtdf2.
	(gcc-quad-routines): Remove sqrttf2.
	* sysdeps/nios2/Makefile [$(subdir) = soft-fp] (sysdep_routines):
	Do not filter out sqrtsf2 and sqrtdf2.
	* sysdeps/powerpc/nofpu/Makefile [$(subdir) = soft-fp]
	(sysdep_routines): Add sqrtsf2 and sqrtdf2.
2018-06-01 17:25:12 +00:00
Joseph Myers
69a01461ee Add narrowing multiply functions.
This patch adds the narrowing multiply functions from TS 18661-1 to
glibc's libm: fmul, fmull, dmull, f32mulf64, f32mulf32x, f32xmulf64
for all configurations; f32mulf64x, f32mulf128, f64mulf64x,
f64mulf128, f32xmulf64x, f32xmulf128, f64xmulf128 for configurations
with _Float64x and _Float128; __nldbl_dmull for ldbl-opt.

The changes are mostly essentially the same as for the narrowing add
functions, so the description of those generally applies to this patch
as well.  f32xmulf64 for i386 cannot use precision control as used for
add and subtract, because that would result in double rounding for
subnormal results, so that uses round-to-odd with long double
intermediate result instead.  The soft-fp support involves adding a
new FP_TRUNC_COOKED since soft-fp multiplication uses cooked inputs
and outputs.

Tested for x86_64, x86, mips64 (all three ABIs, both hard and soft
float) and powerpc, and with build-many-glibcs.py.

	* math/Makefile (libm-narrow-fns): Add mul.
	(libm-test-funcs-narrow): Likewise.
	* math/Versions (GLIBC_2.28): Add narrowing multiply functions.
	* math/bits/mathcalls-narrow.h (mul): Use __MATHCALL_NARROW.
	* math/gen-auto-libm-tests.c (test_functions): Add mul.
	* math/math-narrow.h (CHECK_NARROW_MUL): New macro.
	(NARROW_MUL_ROUND_TO_ODD): Likewise.
	(NARROW_MUL_TRIVIAL): Likewise.
	* soft-fp/op-common.h (FP_TRUNC_COOKED): Likewise.
	* sysdeps/ieee754/float128/float128_private.h (__fmull): New
	macro.
	(__dmull): Likewise.
	* sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add fmul and
	dmul.
	(CFLAGS-nldbl-dmul.c): New variable.
	(CFLAGS-nldbl-fmul.c): Likewise.
	* sysdeps/ieee754/ldbl-opt/Versions (GLIBC_2.28): Add
	__nldbl_dmull.
	* sysdeps/ieee754/ldbl-opt/nldbl-compat.h (__nldbl_dmull): New
	prototype.
	* manual/arith.texi (Misc FP Arithmetic): Document fmul, fmull,
	dmull, fMmulfN, fMmulfNx, fMxmulfN and fMxmulfNx.
	* math/auto-libm-test-in: Add tests of mul.
	* math/auto-libm-test-out-narrow-mul: New generated file.
	* math/libm-test-narrow-mul.inc: New file.
	* sysdeps/i386/fpu/s_f32xmulf64.c: Likewise.
	* sysdeps/ieee754/dbl-64/s_f32xmulf64.c: Likewise.
	* sysdeps/ieee754/dbl-64/s_fmul.c: Likewise.
	* sysdeps/ieee754/float128/s_f32mulf128.c: Likewise.
	* sysdeps/ieee754/float128/s_f64mulf128.c: Likewise.
	* sysdeps/ieee754/float128/s_f64xmulf128.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_dmull.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_f64xmulf128.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_fmull.c: Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_dmull.c: Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_fmull.c: Likewise.
	* sysdeps/ieee754/ldbl-96/s_dmull.c: Likewise.
	* sysdeps/ieee754/ldbl-96/s_fmull.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/nldbl-dmul.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/nldbl-fmul.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_dmull.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_fmul.c: Likewise.
	* sysdeps/ieee754/soft-fp/s_fmull.c: Likewise.
	* sysdeps/powerpc/fpu/libm-test-ulps: Update.
	* sysdeps/mach/hurd/i386/libm.abilist: Likewise.
	* 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/riscv/rv64/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/x86_64/64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
2018-05-16 00:05:28 +00:00
Joseph Myers
049375e2b5 Do not use packed structures in soft-fp.
Building for soft-float ColdFire produces an error in soft-fp:

In file included from ../sysdeps/ieee754/soft-fp/s_fmaf.c:42:
../soft-fp/single.h:85:3: error: 'packed' attribute ignored for field of type 'struct <anonymous>' [-Werror=attributes]
   } bits __attribute__ ((packed));
   ^

While this error only appears in that particular case, this attribute
is in fact never useful, on any architecture.  If you have

  struct __attribute__ ((packed)) { ... } bits;

or

  struct { ... } __attribute__ ((packed)) bits;

then the attribute affects the layout of the structure type.  But with
the form used in this code

  struct { ... } bits __attribute__ ((packed));

the field bits is being declared packed, but the layout of its type
has already been determined at that point.  If on any platform the
layout of the sequence of bit-fields were wrong without the use of a
packed attribute, the attribute would need to be used via a definition
of _FP_STRUCT_LAYOUT, not in its present position.

So this patch removes the useless attribute to fix the build for
ColdFire soft-float.  Tested with build-many-glibcs.py that installed
stripped shared libraries are unchanged by the patch.

	* soft-fp/double.h (union _FP_UNION_D): Do not use attribute
	packed on bits.
	* soft-fp/extended.h (union _FP_UNION_E): Likewise.
	* soft-fp/half.h (union _FP_UNION_H): Likewise.
	* soft-fp/quad.h (union _FP_UNION_Q): Likewise.
	* soft-fp/single.h (union _FP_UNION_S): Likewise.
2018-02-01 20:44:49 +00:00
Joseph Myers
688903eb3e Update copyright dates with scripts/update-copyrights.
* All files with FSF copyright notices: Update copyright dates
	using scripts/update-copyrights.
	* locale/programs/charmap-kw.h: Regenerated.
	* locale/programs/locfile-kw.h: Likewise.
2018-01-01 00:32:25 +00:00
Joseph Myers
6f7c009282 Add sysdeps/ieee754/soft-fp.
The default sysdeps/ieee754 fma implementations rely on exceptions and
rounding modes to achieve correct results through internal use of
round-to-odd.  Thus, glibc configurations without support for
exceptions and rounding modes instead need to use implementations of
fma based on soft-fp.

At present, this is achieved via having implementation files in
soft-fp/ that are #included by sysdeps files for each glibc
configuration that needs them.  In general this means such a
configuration has its own s_fma.c and s_fmaf.c.

TS 18661-1 adds functions that do an operation (+ - * / sqrt fma) on
arguments wider than the return type, with a single rounding of the
infinite-precision result to that return type.  These are also
naturally implemented using round-to-odd on platforms with hardware
support for rounding modes and exceptions but lacking hardware support
for these narrowing operations themselves.  (Platforms that have
direct hardware support for such narrowing operations include at least
ia64, and Power ISA 2.07 or later, which I think means POWER8 or
later.)

So adding the remaining TS 18661-1 functions would mean at least six
narrowing function implementations (fadd fsub fmul fdiv ffma fsqrt),
with aliases for other types and further implementations in some
configurations, that need to be overridden for configurations lacking
hardware exceptions and rounding modes.  Requiring all such
configurations (currently seven of them) to have their own source
files for all those functions seems undesirable.

Thus, this patch adds a directory sysdeps/ieee754/soft-fp to contain
libm function implementations based on soft-fp.  This directory is
then used via Implies from all the configurations that need it, so no
more files need adding to every such configuration when adding more
functions with soft-fp implementations.  A configuration can still
selectively #include a particular file from this directory if desired;
thus, the MIPS #include of the fmal implementation is retained, since
that's appropriate even for hard float (because long double is always
implementated in software for MIPS64, so the soft-fp implementation of
fmal is better than the ldbl-128 one).

This also provides additional motivation for my recent patch removing
--with-fp / --without-fp: previously there was no need for correct use
of --without-fp for no-FPU ARM or SH3, and now we have autodetection
nofpu/ sysdeps directories can be used by this patch for those
configurations without imposing any new requirements on how glibc is
configured.

(The mips64/*/fpu/s_fma.c files added by this patch are needed to keep
the dbl-64 version of fma for double, rather than the ldbl-128 one,
used in that case.)

Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by this patch.

	* soft-fp/fmadf4.c: Move to ....
	* sysdeps/ieee754/soft-fp/s_fma.c: ... here.
	* soft-fp/fmasf4.c: Move to ....
	* sysdeps/ieee754/soft-fp/s_fmaf.c: ... here.
	* soft-fp/fmatf4.c: Move to ....
	* sysdeps/ieee754/soft-fp/s_fmal.c: ... here.
	* sysdeps/ieee754/soft-fp/Makefile: New file.
	* sysdeps/arm/preconfigure.ac: Define with_fp_cond.
	* sysdeps/arm/preconfigure: Regenerated.
	* sysdeps/arm/nofpu/Implies: New file.
	* sysdeps/arm/s_fma.c: Remove file.
	* sysdeps/arm/s_fmaf.c: Likewise.
	* sysdeps/m68k/coldfire/nofpu/Implies: New file.
	* sysdeps/m68k/coldfire/nofpu/s_fma.c: Remove file.
	* sysdeps/m68k/coldfire/nofpu/s_fmaf.c: Likewise.
	* sysdeps/microblaze/Implies: Add ieee754/soft-fp.
	* sysdeps/microblaze/s_fma.c: Remove file.
	* sysdeps/microblaze/s_fmaf.c: Likewise.
	* sysdeps/mips/mips32/nofpu/Implies: New file.
	* sysdeps/mips/mips64/n32/fpu/s_fma.c: Likewise.
	* sysdeps/mips/mips64/n32/nofpu/Implies: Likewise.
	* sysdeps/mips/mips64/n64/fpu/s_fma.c: Likewise.
	* sysdeps/mips/mips64/n64/nofpu/Implies: Likewise.
	* sysdeps/mips/ieee754/s_fma.c: Remove file.
	* sysdeps/mips/ieee754/s_fmaf.c: Likewise.
	* sysdeps/mips/ieee754/s_fmal.c: Update include for move of fmal
	implementation.
	* sysdeps/nios2/Implies: Add ieee754/soft-fp.
	* sysdeps/nios2/s_fma.c: Remove file.
	* sysdeps/nios2/s_fmaf.c: Likewise.
	* sysdeps/sh/nofpu/Implies: New file.
	* sysdeps/sh/s_fma.c: Remove file.
	* sysdeps/sh/s_fmaf.c: Likewise.
	* sysdeps/tile/Implies: Add ieee754/soft-fp.
	* sysdeps/tile/s_fma.c: Remove file.
	* sysdeps/tile/s_fmaf.c: Likewise.
2017-12-12 23:35:21 +00:00
Joseph Myers
541f19baf8 Use libm_alias_* in soft-fp.
This patch makes the soft-fp implementations of fma functions use the
libm_alias_* macros.

Tested with build-many-glibcs.py that installed stripped shared
libraries are unchanged by the patch.

	* soft-fp/fmadf4.c: Include <libm-alias-double.h>.
	[!__fma] (fma): Define using libm_alias_double.
	* soft-fp/fmasf4.c: Include <libm-alias-float.h>.
	[!__fmaf] (fmaf): Define using libm_alias_float.
	* soft-fp/fmatf4.c: Include <libm-alias-ldouble.h>.
	(fmal): Define using libm_alias_ldouble.
2017-10-11 00:03:46 +00:00
Joseph Myers
c10c5267a8 Remove non-add-on Banner files.
Various subdirectories of glibc include Banner files to put some text
in the output of executing libc.so.6, under "Available extensions".

Some of those subdirectories (e.g. crypt) may originally have been
add-ons (and so optional, so a particular glibc build might or might
not have included them), but except for libidn they aren't now (or if
only included in some builds, in the case of soft-fp, the inclusion
depends on the architecture for which glibc is configured rather than
having any glibc configuration for which it's an optional feature),
and it doesn't seem useful for the libc.so.6 output to call out a few
features like that.

This patch removes the non-add-on Banner files, updating contrib.texi
where they noted contributions not otherwise mentioned there.

Tested for x86_64.

	* crypt/Banner: Remove file.
	* nptl/Banner: Likewise.
	* resolv/Banner: Likewise.
	* soft-fp/Banner: Likewise.
	* nptl/Makefile ($(objpfx)banner.h): Remove rule.
	($(objpfx)version.d): Remove dependency on banner.h.
	($(objpfx)version.os): Likewise.
	* nptl/version.c (banner): Do not include banner.h.
	* manual/contrib.texi: Update entries for Richard Henderson, Jakub
	Jelinek and BIND code.
2017-09-21 17:49:51 +00:00
Zack Weinberg
9090848d06 Narrowing the visibility of libc-internal.h even further.
posix/wordexp-test.c used libc-internal.h for PTR_ALIGN_DOWN; similar
to what was done with libc-diag.h, I have split the definitions of
cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN
to a new header, libc-pointer-arith.h.

It then occurred to me that the remaining declarations in libc-internal.h
are mostly to do with early initialization, and probably most of the
files including it, even in the core code, don't need it anymore.  Indeed,
only 19 files actually need what remains of libc-internal.h.  23 others
need libc-diag.h instead, and 12 need libc-pointer-arith.h instead.
No file needs more than one of them, and 16 don't need any of them!

So, with this patch, libc-internal.h stops including libc-diag.h as
well as losing the pointer arithmetic macros, and all including files
are adjusted.

        * include/libc-pointer-arith.h: New file.  Define
	cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and
        PTR_ALIGN_DOWN here.
        * include/libc-internal.h: Definitions of above macros
	moved from here.  Don't include libc-diag.h anymore either.
	* posix/wordexp-test.c: Include stdint.h and libc-pointer-arith.h.
        Don't include libc-internal.h.

	* debug/pcprofile.c, elf/dl-tunables.c, elf/soinit.c, io/openat.c
	* io/openat64.c, misc/ptrace.c, nptl/pthread_clock_gettime.c
	* nptl/pthread_clock_settime.c, nptl/pthread_cond_common.c
	* string/strcoll_l.c, sysdeps/nacl/brk.c
	* sysdeps/unix/clock_settime.c
	* sysdeps/unix/sysv/linux/i386/get_clockfreq.c
	* sysdeps/unix/sysv/linux/ia64/get_clockfreq.c
	* sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c
	* sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c:
	Don't include libc-internal.h.

	* elf/get-dynamic-info.h, iconv/loop.c
	* iconvdata/iso-2022-cn-ext.c, locale/weight.h, locale/weightwc.h
	* misc/reboot.c, nis/nis_table.c, nptl_db/thread_dbP.h
	* nscd/connections.c, resolv/res_send.c, soft-fp/fmadf4.c
	* soft-fp/fmasf4.c, soft-fp/fmatf4.c, stdio-common/vfscanf.c
	* sysdeps/ieee754/dbl-64/e_lgamma_r.c
	* sysdeps/ieee754/dbl-64/k_rem_pio2.c
	* sysdeps/ieee754/flt-32/e_lgammaf_r.c
	* sysdeps/ieee754/flt-32/k_rem_pio2f.c
	* sysdeps/ieee754/ldbl-128/k_tanl.c
	* sysdeps/ieee754/ldbl-128ibm/k_tanl.c
	* sysdeps/ieee754/ldbl-96/e_lgammal_r.c
	* sysdeps/ieee754/ldbl-96/k_tanl.c, sysdeps/nptl/futex-internal.h:
	Include libc-diag.h instead of libc-internal.h.

        * elf/dl-load.c, elf/dl-reloc.c, locale/programs/locarchive.c
        * nptl/nptl-init.c, string/strcspn.c, string/strspn.c
	* malloc/malloc.c, sysdeps/i386/nptl/tls.h
	* sysdeps/nacl/dl-map-segments.h, sysdeps/x86_64/atomic-machine.h
	* sysdeps/unix/sysv/linux/spawni.c
        * sysdeps/x86_64/nptl/tls.h:
        Include libc-pointer-arith.h instead of libc-internal.h.

	* elf/get-dynamic-info.h, sysdeps/nacl/dl-map-segments.h
	* sysdeps/x86_64/atomic-machine.h:
        Add multiple include guard.
2017-03-01 20:33:46 -05:00
Jakub Jelinek
af1a265da0 * soft-fp/op-common.h (_FP_MUL, _FP_FMA, _FP_DIV): Add
/* FALLTHRU */ comments.
2017-01-24 23:27:36 +01:00
Joseph Myers
bfff8b1bec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
James Greenhalgh
87ab10d652 [soft-fp] Add support for various half-precision conversion routines.
This patch adds conversion routines required for _Float16 support in
AArch64.

These are one-step conversions to and from TImode and TFmode. We need
these on AArch64 regardless of presence of the ARMv8.2-A 16-bit
floating-point extensions.

In the patch, soft-fp/half.h is derived from soft-fp/single.h .  The
conversion routines are derivatives of their respective SFmode
variants.

	* soft-fp/extendhftf2.c: New.
	* soft-fp/fixhfti.c: Likewise.
	* soft-fp/fixunshfti.c: Likewise.
	* soft-fp/floattihf.c: Likewise.
	* soft-fp/floatuntihf.c: Likewise.
	* soft-fp/half.h: Likewise.
	* soft-fp/trunctfhf2.c: Likewise.
2016-09-21 21:02:54 +00:00
Joseph Myers
c20809709a Fix soft-fp extended.h unpacking (GCC bug 77265).
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.
2016-08-16 17:11:46 +00:00
Joseph Myers
f7a9f785e5 Update copyright dates with scripts/update-copyrights. 2016-01-04 16:05:18 +00:00
Joseph Myers
f1d237df1e Remove GCC version conditionals on -Wmaybe-uninitialized pragmas.
One common case of __GNUC_PREREQ (4, 7) conditionals is use of
diagnostic control pragmas for -Wmaybe-uninitialized, an option
introduced in GCC 4.7 where older GCC needed -Wuninitialized to be
controlled instead if the warning appeared with older GCC.  This patch
removes such conditionals.

(There remain several older uses of -Wno-uninitialized in makefiles
that still need to be converted to diagnostic control pragmas if the
issue is still present with current sources and supported GCC
versions, and it's likely that in most cases those pragmas also will
end up controlling -Wmaybe-uninitialized.)

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch, except for libresolv
since res_send.c contains assertions whose line numbers are changed by
the patch).

	* resolv/res_send.c (send_vc) [__GNUC_PREREQ (4, 7)]: Make code
	unconditional.
	* soft-fp/fmadf4.c [__GNUC_PREREQ (4, 7)]: Likewise.
	[!__GNUC_PREREQ (4, 7)]: Remove conditional code.
	* soft-fp/fmasf4.c [__GNUC_PREREQ (4, 7)]: Make code
	unconditional.
	[!__GNUC_PREREQ (4, 7)]: Remove conditional code.
	* soft-fp/fmatf4.c [__GNUC_PREREQ (4, 7)]: Make code
	unconditional.
	[!__GNUC_PREREQ (4, 7)]: Remove conditional code.
	* stdlib/setenv.c
	[((__GNUC__ << 16) + __GNUC_MINOR__) >= ((4 << 16) + 7)]: Make
	code unconditional.
	[!(((__GNUC__ << 16) + __GNUC_MINOR__) >= ((4 << 16) + 7))]:
	Remove conditional code.
	* sysdeps/ieee754/dbl-64/e_lgamma_r.c
	(__ieee754_lgamma_r) [__GNUC_PREREQ (4, 7)]: Make code
	unconditional.
	(__ieee754_lgamma_r) [!__GNUC_PREREQ (4, 7)]: Remove conditional
	code.
	* sysdeps/ieee754/flt-32/e_lgammaf_r.c
	(__ieee754_lgammaf_r) [__GNUC_PREREQ (4, 7)]: Make code
	unconditional.
	(__ieee754_lgammaf_r) [!__GNUC_PREREQ (4, 7)]: Remove conditional
	code.
	* sysdeps/ieee754/ldbl-128/k_tanl.c
	(__kernel_tanl) [__GNUC_PREREQ (4, 7)]: Make code unconditional.
	(__kernel_tanl) [!__GNUC_PREREQ (4, 7)]: Remove conditional code.
	* sysdeps/ieee754/ldbl-128ibm/k_tanl.c
	(__kernel_tanl) [__GNUC_PREREQ (4, 7)]: Make code unconditional.
	(__kernel_tanl) [!__GNUC_PREREQ (4, 7)]: Remove conditional code.
	* sysdeps/ieee754/ldbl-96/e_lgammal_r.c
	(__ieee754_lgammal_r) [__GNUC_PREREQ (4, 7)]: Make code
	unconditional.
	(__ieee754_lgammal_r) [!__GNUC_PREREQ (4, 7)]: Remove conditional
	code.
	* sysdeps/ieee754/ldbl-96/k_tanl.c
	(__kernel_tanl) [__GNUC_PREREQ (4, 7)]: Make code unconditional.
	(__kernel_tanl) [!__GNUC_PREREQ (4, 7)]: Remove conditional code.
2015-10-27 23:42:20 +00:00
Steve Ellcey
37430363b8 Fix undefined warning messages in GCC 6.
GCC 6 puts out warnings in a different location then GCC 5.  Move the
    DIAG macros so that the warnings are supressed for both compilers.

    ChangeLog:

	* soft-fp/fmasf4.c: Add include of sys/cdefs.h.
	Move DIAG_PUSH_NEEDS_COMMENT, DIAG_IGNORE_NEEDS_COMMENT to front of
	file, move DIAG_POP_NEEDS_COMMENT to end of file.
	* soft-fp/fmadf4.c: Ditto.
	* soft-fp/fmatf4.c: Ditto.
2015-08-27 08:09:49 -07:00
Joseph Myers
dc6b5aed1b Fix soft-fp fma for -Wuninitialized.
The soft-fp implementations of fma produce -Wuninitialized warnings
because, in the cases where the result is not a nonzero finite value,
the soft-fp does not set the exponent of the result since the (cooked)
packing will do so, but the compiler does not then see that the
exponent is always set in packing before it's used if it wasn't set
earlier.  This patch uses DIAG_* macros to suppress those warnings.

Tested for mips64.  (In fact this allows the mips64 build to complete
with the -Wno-uninitialized removed from math/Makefile, but more
cleanups are still needed in the ldbl-128ibm code for uninitialized
warnings there.)

	* soft-fp/fmadf4.c: Include <libc-internal.h>.
	(__fma): Ignore uninitialized warnings around packing.
	* soft-fp/fmasf4.c: Include <libc-internal.h>.
	(__fmaf): Ignore uninitialized warnings around packing.
	* soft-fp/fmatf4.c: Include <libc-internal.h>.
	(__fmal): Ignore uninitialized warnings around packing.
2015-05-22 20:28:50 +00:00
Richard Henderson
85bae5a160 soft-fp: Fix alpha kernel build problem
* soft-fp/op-common.h (_FP_FROM_INT): Don't write to R.
2015-05-19 11:23:56 -07:00
Joseph Myers
7d67a196b6 soft-fp: Define and use _FP_STATIC_ASSERT.
This patch makes soft-fp use static assertions in place of conditional
calls to abort, in places where there are checks for conditions (on
the types for which a macro is used) that the code is not prepared to
handle.  The fallback definition of _FP_STATIC_ASSERT (for kernel use
only, as only relevant to compilers not supported for building glibc)
is as in misc/sys/cdefs.h.

This means that soft-fp only ever calls abort for _FP_UNREACHABLE
calls in builds with GCC versions before 4.5.  Thus, there is no need
for an abort declaration or <stdlib.h> include, since the kernel code
handles defining abort as a macro itself - and so this avoids any need
for an __KERNEL__ condition on the abort declaration to avoid it
breaking with the kernel's macro definition.  That is, this patch is
intended to make glibc's soft-fp code suitable for kernel use with no
kernel-local changes to the soft-fp code needed at all.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by the patch.  One explicit <stdlib.h> include had to be
added to a file that was relying on the include from soft-fp.h.

	* soft-fp/soft-fp.h (_FP_STATIC_ASSERT): New macro.
	[_LIBC]: Do not include <stdlib.h>.
	[!_LIBC] (abort): Remove declaration.
	* soft-fp/op-2.h (_FP_MUL_MEAT_2_120_240_double): Use
	_FP_STATIC_ASSERT instead of conditionally calling abort.
	* soft-fp/op-common.h (_FP_FROM_INT): Likewise.
	(_FP_EXTEND_CNAN): Likewise.
	(FP_TRUNC): Likewise.
	(__FP_CLZ): Likewise.
	* sysdeps/powerpc/nofpu/flt-rounds.c: Include <stdlib.h>.
2015-03-12 18:43:21 +00:00
Joseph Myers
068a627455 soft-fp: Add _FP_UNREACHABLE.
This patch makes soft-fp use a new macro _FP_UNREACHABLE in place of
calling abort in unreachable default cases of switch statements.
_FP_UNREACHABLE expands to call __builtin_unreachable for GCC 4.5 and
later; the fallback to abort is thus only for kernel use.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.  Also tested with the math/ tests for mips64
(in the case of fma there *was* previously an abort call generated,
unlike for the other operations - one switch only deals with a subset
of classes for one operand based on what could have been generated in
the earlier part of fma, whereas the other switches deal with all
combinations of two classes - and this is apparently too complicated
for the default case to have been optimized away).

	* soft-fp/soft-fp.h (_FP_UNREACHABLE): New macro.
	* soft-fp/op-common.h (_FP_MUL): Use _FP_UNREACHABLE instead of
	abort.
	(_FP_FMA): Likewise.
	(_FP_DIV): Likewise.
2015-03-11 01:14:34 +00:00
Joseph Myers
a2f8be9c83 soft-fp: Use multiple-include guards.
This patch makes soft-fp headers consistently use multiple-include
guards, something previously done mainly only in the Linux kernel
version.  The guard macros aren't the same as those used in the Linux
kernel, but there seems to be enough variation in such guards in Linux
kernel code that hopefully this version will be acceptable there.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/double.h [SOFT_FP_DOUBLE_H]: New multiple-include guard.
	* soft-fp/extended.h [SOFT_FP_EXTENDED_H]: Likewise.
	* soft-fp/op-1.h [SOFT_FP_OP_1_H]: Likewise.
	* soft-fp/op-2.h [SOFT_FP_OP_2_H]: Likewise.
	* soft-fp/op-4.h [SOFT_FP_OP_4_H]: Likewise.
	* soft-fp/op-8.h [SOFT_FP_OP_8_H]: Likewise.
	* soft-fp/op-common.h [SOFT_FP_OP_COMMON_H]: Likewise.
	* soft-fp/quad.h [SOFT_FP_QUAD_H]: Likewise.
	* soft-fp/single.h [SOFT_FP_SINGLE_H]: Likewise.
	* soft-fp/soft-fp.h (SOFT_FP_H): Define to 1 rather than empty.
	Add comment on closing #endif.
2015-03-10 00:32:29 +00:00
Joseph Myers
b838844bc5 soft-fp: Support conditional zero-initialization in declarations.
In the Linux kernel, some architectures have a single function that
uses different kinds of unpacking and packing depending on the
instruction being emulated, meaning it is not readily visible to the
compiler that variables from _FP_DECL and _FP_FRAC_DECL_* macros are
only used in cases where they were initialized.  The existing copy of
soft-fp in the Linux kernel uses zero-initialization to avoid warnings
in this case, so while frowned upon as a warning suppression mechanism
in code built for glibc it seems appropriate to have such
zero-initialization conditional on __KERNEL__.  This patch duly adds
it, via a macro _FP_ZERO_INIT that expands to empty for non-kernel
compilations.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/soft-fp.h (_FP_ZERO_INIT): New macro.  Define depending
	on [__KERNEL__].
	* soft-fp/op-1.h (_FP_FRAC_DECL_1): Use _FP_ZERO_INIT.
	* soft-fp/op-2.h (_FP_FRAC_DECL_2): Likewise.
	* soft-fp/op-common.h (_FP_DECL): Likewise.
2015-03-07 01:39:42 +00:00
Joseph Myers
0b3467b344 Fix /* in comment in previous commit. 2015-03-07 00:59:56 +00:00
Joseph Myers
fa9dda6493 soft-fp: Condition sfp-machine.h include path on __KERNEL__.
My Linux kernel patch to update the kernel to current glibc soft-fp
<https://sourceware.org/ml/libc-alpha/2015-02/msg00107.html> still
leaves a few small differences between the two copies of soft-fp.

I think it's desirable to avoid such differences completely if
possible by having one set of sources suitable for use in both places.
To that end, this patch introduces a conditional on __KERNEL__ for the
path by which sfp-machine.h is included.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/soft-fp.h [!_LIBC && __KERNEL__]: Include
	<asm/sfp-machine.h> instead of <sfp-machine.h>.
2015-03-07 00:36:02 +00:00
Joseph Myers
e4a399dc3d soft-fp: Adjust call to abort for kernel use.
soft-fp calls abort in various cases that the code doesn't handle, all
cases that should never actually occur for any supported choice of
types.

Calling an abort function is not appropriate for kernel use, so the
Linux kernel redefines abort as a macro in various ways in the ports
using this code, typically to "return 0" or similar.

One use of abort in soft-fp is inside a comma expression and doesn't
work with such a macro.  This patch changes it to use a statement
expression.

Tested for powerpc-nofpu that installed shared libraries are unchanged
by this patch.

(There are two classes of aborts: those to make control flow visible
to the compiler, in default cases of switches over _FP_CLS_COMBINE,
which could reasonably change to __builtin_unreachable for glibc but
would still need to handle pre-4.5 compilers for kernel use, and those
intended to detect any use of soft-fp for combinations of types the
code doesn't know how to handle, which could reasonably become link
failures if the calls should always be optimized away.  But those are
separate possible future enhancements.)

	* soft-fp/op-common.h (_FP_FROM_INT): Wrap call to abort in
	expression inside statement expression.
2015-02-20 18:07:03 +00:00
Joseph Myers
1c7a4a51a3 soft-fp: Fix _FP_FMA when product is zero and third argument is finite (bug 17932).
soft-fp's _FP_FMA fails to set the result's exponent for cases where
the result of the multiplication is 0, yielding incorrect (arbitrary,
depending on uninitialized values) results for those cases.  This
affects libm for architectures using soft-fp to implement fma.  This
patch adds the exponent setting and tests for this case.

Tested for ARM soft-float (which uses soft-fp fma), x86_64 and x86 (to
verify not introducing new libm test failures there).

(This bug showed up in testing my patch to move the Linux kernel to
current soft-fp.  math/Makefile has "override CFLAGS +=
-Wno-uninitialized" which would have stopped compiler warnings from
showing up this problem, although I wouldn't be surprised if removing
that shows spurious warnings from this code, if the compiler fails to
follow that various cases where the exponent is uninitialized don't
need it initialized because the class is set to a value meaning the
uninitialized exponent isn't used.)

	[BZ #17932]
	* soft-fp/op-common.h (_FP_FMA): Set exponent of result in case
	where multiplication results in zero and third argument is finite
	and nonzero.
	* math/auto-libm-test-in: Add more tests of fma.
	* math/auto-libm-test-out: Regenerated.
2015-02-06 15:44:07 +00:00
Joseph Myers
61f006c12d soft-fp: Refine FP_EX_DENORM handling for comparisons.
In <https://sourceware.org/ml/libc-alpha/2014-09/msg00488.html>, I
noted that comparisons in soft-fp did not set FP_EX_DENORM unless
denormal operands were flushed to zero.

This patch fixes soft-fp to check for denormal operands for
comparisons and set that exception whenever FP_EX_DENORM is not zero.
In particular, for the one architecture for which the Linux kernel
defines FP_EX_DENORM (alpha), this corresponds to the existing logic
for comparisons and so allows that logic to be replaced by a simple
call to FP_CMP_D when soft-fp is updated in the kernel.

Tested for powerpc (e500) that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/op-common.h (_FP_CMP_CHECK_DENORM): New macro.
	(_FP_CMP_CHECK_FLUSH_ZERO): Likewise.
	(_FP_CMP): Use_FP_CMP_CHECK_DENORM and _FP_CMP_CHECK_FLUSH_ZERO.
	(_FP_CMP_EQ): Likewise.
	(_FP_CMP_UNORD): Use _FP_CMP_CHECK_DENORM.
2015-02-06 15:41:49 +00:00
Joseph Myers
639e42eb90 soft-fp: Support floating-point extensions without quieting sNaNs.
One special case needed in soft-fp to replace the old version in the
Linux kernel is extending from a narrower floating-point format to a
wider one without quieting signaling NaNs.  (This is for
arch/powerpc/math-emu/lfs.c, where previously it used the old FP_CONV
which didn't do anything special for NaNs, then handled packing
specially for NaNs to avoid quieting at packing time, and discarded
the exceptions from unpacking.)

This patch accordingly refactors FP_EXTEND, creating a separate
_FP_EXTEND_CNAN that offers a choice of how NaNs are handled, with
FP_EXTEND reimplemented as a wrapper that provides the common case of
the IEEE operation that does quiet signaling NaNs and raise exceptions
for them.

Tested for powerpc (e500) that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/op-common.h (FP_EXTEND): Rename to _FP_EXTEND_CNAN with
	extra argument CHECK_NAN.  Redefine as wrapper around
	_FP_EXTEND_CNAN.
2015-02-06 15:39:17 +00:00
Joseph Myers
d7423856b5 soft-fp: Use __label__ for all labels within macros.
soft-fp has various macros containing labels and goto statements.
Because label names are function-scoped, this is problematic for using
the same macro more than once within a function, which some
architectures do in the Linux kernel (the soft-fp version there
predates the addition of any of these labels and gotos).  This patch
fixes this by using __label__ to make the labels local to the block
with the __label__ declaration.

Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.

	* soft-fp/op-common.h (_FP_ADD_INTERNAL): Declare labels with
	__label__.
	(_FP_FMA): Likewise.
	(_FP_TO_INT_ROUND): Likewise.
	(_FP_FROM_INT): Likewise.
2015-01-22 22:39:26 +00:00
Joseph Myers
b168057aaa Update copyright dates with scripts/update-copyrights. 2015-01-02 16:29:47 +00:00
Joseph Myers
2004e7fb76 soft-fp: Add _FP_TO_INT_ROUND.
Continuing the series of patches adding soft-fp features from the
kernel version of soft-fp to glibc so that glibc's version is able to
replace the old fork of soft-fp in the kernel, this patch adds the
last major such feature: _FP_TO_INT_ROUND, converting a floating-point
number to an integer with rounding according to the current rounding
direction (as opposed to truncating towards zero, which _FP_TO_INT
does).

The general structure of the implementation follows that of
_FP_TO_INT, but of course is more complicated.  As with glibc's
_FP_TO_INT it works with raw input (the kernel versions of these
macros predate the conversion of _FP_TO_INT and many other macros to
raw or semi-raw input).  I have not tried to work out what bugs there
might be in the kernel version that this might fix; it's a
from-scratch implementation based on _FP_TO_INT.

Tested for powerpc (soft-float) that there is no change to the
installed shared libraries; also tested with the libm tests with lrint
/ lrintf / llrint / llrintf made to use _FP_TO_INT_ROUND, to provide
some test of the functionality.  As we don't have benchmarks for those
functions, I haven't actually included the soft-fp versions of them,
although I expect them to be faster than the existing code (given that
the existing code involves adding and subtracting numbers such as
0x1p52 to achieve the desired rounding, which is not particularly
efficient when the underlying floating point is software floating
point).

2014-11-04  Joseph Myers  <joseph@codesourcery.com>

	* soft-fp/op-common.h (_FP_TO_INT_ROUND): New macro.
	* soft-fp/double.h [_FP_W_TYPE_SIZE < 64] (FP_TO_INT_ROUND_D): New
	macro.
	[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_ROUND_D): Likewise.
	* soft-fp/extended.h [_FP_W_TYPE_SIZE < 64] (FP_TO_INT_ROUND_E):
	New macro.
	[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_ROUND_E): Likewise.
	* soft-fp/quad.h [_FP_W_TYPE_SIZE < 64] (FP_TO_INT_ROUND_Q): New
	macro.
	[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_ROUND_Q): Likewise.
	* soft-fp/single.h (FP_TO_INT_ROUND_S): New macro.
2014-11-04 16:34:49 +00:00
Joseph Myers
5c0508a318 soft-fp: Use parentheses around macro arguments.
This patch cleans up the soft-fp code to use parentheses around macro
arguments (where possible; many macro arguments are identifiers used
with ## rather than arbitrary expressions, so cannot be put in
parentheses).  (I'm not aware of any bugs caused by the lack of
parentheses, but this is generally good practice.  The patch is not
exhaustive regarding internal macros where the arguments always come
directly from the mantissa of a floating-point number, although
probably those should be cleaned up in this regard as well.)

Tested for powerpc-nofpu that the installed shared libraries are
unchanged by this patch.

	* soft-fp/double.h [_FP_W_TYPE_SIZE < 64] (FP_UNPACK_RAW_D): Use
	parentheses around macro arguments.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_RAW_DP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_RAW_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_RAW_DP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_DP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_SEMIRAW_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_SEMIRAW_DP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_DP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_SEMIRAW_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_SEMIRAW_DP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (_FP_SQRT_MEAT_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_EQ_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_UNORD_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_TO_INT_D): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_FROM_INT_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_RAW_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_RAW_DP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_RAW_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_RAW_DP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_DP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_SEMIRAW_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_SEMIRAW_DP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_DP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_SEMIRAW_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_SEMIRAW_DP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (_FP_SQRT_MEAT_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_EQ_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_UNORD_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_D): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_FROM_INT_D): Likewise.
	* soft-fp/extended.h [_FP_W_TYPE_SIZE < 64] (FP_UNPACK_E):
	Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_EP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_SEMIRAW_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_SEMIRAW_EP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_EP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_SEMIRAW_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_SEMIRAW_EP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (_FP_SQRT_MEAT_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_EQ_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_UNORD_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_TO_INT_E): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_FROM_INT_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_EP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_SEMIRAW_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_SEMIRAW_EP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_EP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_SEMIRAW_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_SEMIRAW_EP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (_FP_SQRT_MEAT_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_EQ_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_UNORD_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_E): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_FROM_INT_E): Likewise.
	* soft-fp/op-1.h (_FP_FRAC_SRST_1): Likewise.
	(_FP_FRAC_SRS_1): Likewise.
	(_FP_FRAC_CLZ_1): Likewise.
	(_FP_MUL_MEAT_1_imm): Likewise.
	(_FP_MUL_MEAT_1_wide): Likewise.
	(_FP_MUL_MEAT_1_hard): Likewise.
	(_FP_SQRT_MEAT_1): Likewise.
	(_FP_FRAC_ASSEMBLE_1): Likewise.
	(_FP_FRAC_DISASSEMBLE_1): Likewise.
	* soft-fp/op-2.h (_FP_FRAC_CLZ_2): Likewise.
	(__FP_CLZ_2): Likewise.
	(_FP_MUL_MEAT_2_wide): Likewise.
	(_FP_MUL_MEAT_2_wide_3mul): Likewise.
	(_FP_MUL_MEAT_2_gmp): Likewise.
	(_FP_MUL_MEAT_2_120_240_double): Likewise.
	(_FP_SQRT_MEAT_2): Likewise.
	(_FP_FRAC_ASSEMBLE_2): Likewise.
	(_FP_FRAC_DISASSEMBLE_2): Likewise.
	* soft-fp/op-4.h (_FP_FRAC_SRS_4): Likewise.
	(_FP_FRAC_CLZ_4): Likewise.
	(_FP_MUL_MEAT_4_wide): Likewise.
	(_FP_MUL_MEAT_4_gmp): Likewise.
	(_FP_SQRT_MEAT_4): Likewise.
	(_FP_FRAC_ASSEMBLE_4): Likewise.
	(_FP_FRAC_DISASSEMBLE_4): Likewise.
	* soft-fp/op-common.h (_FP_CMP): Likewise.
	(_FP_CMP_EQ): Likewise.
	(_FP_CMP_UNORD): Likewise.
	(_FP_TO_INT): Likewise.
	(_FP_FROM_INT): Likewise.
	[!__FP_CLZ] (__FP_CLZ): Likewise.
	(_FP_DIV_HELP_imm): Likewise.
	* soft-fp/quad.h [_FP_W_TYPE_SIZE < 64] (FP_UNPACK_RAW_Q):
	Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_RAW_QP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_RAW_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_RAW_QP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_QP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_SEMIRAW_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_UNPACK_SEMIRAW_QP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_QP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_SEMIRAW_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_PACK_SEMIRAW_QP): Likewise.
	[_FP_W_TYPE_SIZE < 64] (_FP_SQRT_MEAT_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_EQ_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_CMP_UNORD_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_TO_INT_Q): Likewise.
	[_FP_W_TYPE_SIZE < 64] (FP_FROM_INT_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_RAW_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_RAW_QP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_RAW_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_RAW_QP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_QP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_SEMIRAW_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_UNPACK_SEMIRAW_QP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_QP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_SEMIRAW_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_PACK_SEMIRAW_QP): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (_FP_SQRT_MEAT_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_EQ_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_CMP_UNORD_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_TO_INT_Q): Likewise.
	[_FP_W_TYPE_SIZE >= 64] (FP_FROM_INT_Q): Likewise.
	* soft-fp/single.h (FP_UNPACK_RAW_S): Likewise.
	(FP_UNPACK_RAW_SP): Likewise.
	(FP_PACK_RAW_S): Likewise.
	(FP_PACK_RAW_SP): Likewise.
	(FP_UNPACK_S): Likewise.
	(FP_UNPACK_SP): Likewise.
	(FP_UNPACK_SEMIRAW_S): Likewise.
	(FP_UNPACK_SEMIRAW_SP): Likewise.
	(FP_PACK_S): Likewise.
	(FP_PACK_SP): Likewise.
	(FP_PACK_SEMIRAW_S): Likewise.
	(FP_PACK_SEMIRAW_SP): Likewise.
	(_FP_SQRT_MEAT_S): Likewise.
	(FP_CMP_S): Likewise.
	(FP_CMP_EQ_S): Likewise.
	(FP_CMP_UNORD_S): Likewise.
	(FP_TO_INT_S): Likewise.
	(FP_FROM_INT_S): Likewise.
2014-10-09 17:05:26 +00:00
Joseph Myers
a736ec370a soft-fp: Support rsigned == 2 in _FP_TO_INT.
Continuing the addition of soft-fp features in the Linux kernel
version, this patch adds _FP_TO_INT support for rsigned == 2 (reduce
overflowing results modulo 2^rsize to fit in the destination, used for
alpha emulation).

The kernel version is buggy; it can left shift by a negative amount
when right shifting is required in an overflow case (the kernel
version also has other bugs fixed long ago in glibc; at least,
spurious exceptions converting to the most negative integer).  This
version avoids that by handling overflow (other than to 0) for rsigned
== 2 along with the normal non-overflow case, which already properly
determines the direction in which to shift.

Tested for powerpc-nofpu.  Some functions get slightly bigger and some
get slightly smaller, no doubt as a result of the change to where in
the macro "inexact" is raised, but I don't think those changes are
significant.  Also tested for powerpc-nofpu with the relevant __fix*
functions changed to use rsigned == 2 (which is after all just as
valid as rsigned == 1 in IEEE terms), including verifying the results
and exceptions for various cases of conversions.

With these seven patches, the one remaining feature to add for the
soft-fp code to have all the features of the kernel version is
_FP_TO_INT_ROUND.

	* soft-fp/op-common.h (_FP_TO_INT): Handle rsigned == 2.
2014-10-09 15:00:37 +00:00
Joseph Myers
ff12c11f45 soft-fp: Support more precise "invalid" exceptions.
As previously discussed
<https://sourceware.org/ml/libc-alpha/2013-10/msg00345.html>, it would
be desirable to be able to use the same version of the soft-fp code in
the Linux kernel as well as in glibc and libgcc (instead of an old
version in the kernel that's missing ten years of bug fixes,
performance improvements and new features), and to that end it is
useful to add to glibc's copy features in the kernel's copy, even when
they are not directly useful in glibc.

To that end, this patch adds one of those features: support for more
precise "invalid" exceptions describing the particular kind of invalid
operation.  These are relevant for powerpc emulation, and are also as
described in IEEE 754-2008 as sub-exceptions.

The set of sub-exceptions here is the union of those supported on
powerpc and those from IEEE 754-2008 (the former adds a distinction
between 0/0 and Inf/Inf; the latter adds a distinction between Inf*0
from multiplication and the same from fma).  This includes
sub-exceptions for sqrt, conversions to integer and comparisons that
are not supported in the kernel; I see no obvious reason for these
being missing from the kernel support, given that they are supported
on powerpc so accurate powerpc emulation should generate them.

Tested for powerpc-nofpu that the disassembly of installed shared
libraries is unchanged by this patch.

	* soft-fp/soft-fp.h (FP_EX_INVALID_SNAN): New macro.
	(FP_EX_INVALID_IMZ): Likewise.
	(FP_EX_INVALID_IMZ_FMA): Likewise.
	(FP_EX_INVALID_ISI): Likewise.
	(FP_EX_INVALID_ZDZ): Likewise.
	(FP_EX_INVALID_IDI): Likewise.
	(FP_EX_INVALID_SQRT): Likewise.
	(FP_EX_INVALID_CVI): Likewise.
	(FP_EX_INVALID_VC): Likewise.
	* soft-fp/op-common.h (_FP_UNPACK_CANONICAL): Specify more precise
	"invalid" exceptions.
	(_FP_CHECK_SIGNAN_SEMIRAW): Likewise.
	(_FP_ADD_INTERNAL): Likewise.
	(_FP_MUL): Likewise.
	(_FP_FMA): Likewise.
	(_FP_DIV): Likewise.
	(_FP_CMP_CHECK_NAN): Likewise.
	(_FP_SQRT): Likewise.
	(_FP_TO_INT): Likewise.
	(FP_EXTEND): Likewise.
2014-10-09 14:59:23 +00:00
Joseph Myers
454ac701e3 soft-fp: Add FP_DENORM_ZERO.
Continuing the addition of soft-fp features used in the Linux kernel,
this patch adds soft-fp support for FP_DENORM_ZERO (flushing input
subnormal operands to zero of the same sign).

There are some differences from the kernel version.  In the kernel,
the "inexact" exception is set when flushing to zero.  This does not
appear to match the documented semantics for either of the
architectures (alpha and sh) for which the kernel uses FP_DENORM_ZERO,
so this patch does not set "inexact" in this case.  More operations
now use raw or semi-raw unpacking for optimization than did in the
ten-year-old soft-fp version in the kernel, so checks of
FP_DENORM_ZERO are inserted in those operations.  They are also
inserted for comparisons (which already used raw unpacking in the old
version) as I believe that's the correct thing to do when input
subnormals are flushed to zero.  They are *not* inserted for _FP_NEG.
(If any processors do flush input subnormals to zero for negation, or
otherwise vary from the rules implemented when FP_DENORM_ZERO is set,
further macros for sfp-machine.h to control this may need to be
added.)

Although the addition for comparisons will cause FP_EX_DENORM to be
set in this case, it still won't be set for comparisons involving
subnormals when not flushed to zero.  It's quite possible that
accurate emulation of processors that have such an exception for
subnormal operands will require further changes relating to when
FP_EX_DENORM is set (in general, the support for things defined by
IEEE should be considered more reliable and mature than the support
for things outside the scope of IEEE floating point).

Although some processors also have a mode for abrupt underflow -
producing zeroes instead of output subnormals - there is no such mode
in the kernel's soft-fp, so no such mode is added to glibc's soft-fp
(although it could be if someone wanted to emulate such processor
support).

Tested for powerpc-nofpu that the disassembly of installed shared
libraries is unchanged by this patch.

	* soft-fp/soft-fp.h (FP_DENORM_ZERO): New macro.
	* soft-fp/op-common.h (_FP_UNPACK_CANONICAL): Check
	FP_DENORM_ZERO.
	(_FP_CHECK_FLUSH_ZERO): New macro.
	(_FP_ADD_INTERNAL): Call _FP_CHECK_FLUSH_ZERO.
	(_FP_CMP): Likewise.
	(_FP_CMP_EQ): Likewise.
	(_FP_TO_INT): Do not set inexact for subnormal arguments if
	FP_DENORM_ZERO.
	(FP_EXTEND): Call _FP_CHECK_FLUSH_ZERO.
	(FP_TRUNC): Likewise.
2014-10-09 01:09:22 +00:00
Joseph Myers
0022e688d0 soft-fp: Fix _FP_TO_INT latent bug in overflow handling.
This patch fixes a latent bug in _FP_TO_INT regarding handling of
arguments with maximum exponent (infinities and NaNs).  If the maximum
exponent is below that calculated as an overflow threshold, such
values would incorrectly be treated as normal values for the purposes
of the conversion.  This could not occur for any of the conversions
actually occurring in glibc, libgcc or the Linux kernel (the maximum
exponent for float is, just, big enough to ensure overflow for
unsigned __int128), but would apply if soft-fp were used for IEEE
binary16.  Appropriate checks are inserted to ensure that the maximum
exponent is always treated as an overflowing exponent, and never as a
normal one.

Tested for powerpc-nofpu that the disassembly of installed shared
libraries is unchanged by this patch.

	* soft-fp/op-common.h (_FP_TO_INT): Ensure maximum exponent is
	treated as invalid conversion, not as normal exponent.
2014-10-09 01:07:10 +00:00
Joseph Myers
73e28d9c88 soft-fp: Refactor exception handling for comparisons.
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.
2014-10-09 01:03:56 +00:00
Joseph Myers
43059f42db soft-fp: Make extensions of subnormals from XFmode to TFmode signal underflow if traps enabled.
This patch fixes a soft-fp corner case I previously noted in
<https://sourceware.org/ml/libc-alpha/2013-10/msg00349.html>: when
trapping on underflow is enabled, extensions of subnormals from XFmode
to TFmode need to signal underflow because the result is tiny (but
exact, so the underflow flag is not raised unless trapping is
enabled).

To avoid any excess initialization or tests for other cases of
floating-point extensions, a new FP_INIT_TRAPPING_EXCEPTIONS is added
that does the initialization required for this particular case (more
than FP_INIT_EXCEPTIONS, less than FP_INIT_ROUNDMODE, in general), and
FP_NO_EXACT_UNDERFLOW is added to stub out FP_TRAPPING_EXCEPTIONS
tests for those cases of extensions where the test would be dead code,
to avoid any uninitialized variable warnings.

As the relevant case only applies in libgcc, not to any use of soft-fp
in glibc, there is no bug report in Bugzilla and no non-default
definitions of FP_INIT_TRAPPING_EXCEPTIONS are added by the patch.  A
testcase will be added to GCC as part of an update of soft-fp in
libgcc once this patch is in libc.

Tested for powerpc-nofpu that the disassembly of installed shared
libraries is unchanged by this patch.  Bootstrapped GCC with updated
soft-fp with no regressions on x86_64-unknown-linux-gnu and verified
that a test of the relevant case passes where it failed before.

	* soft-fp/op-common.h (FP_EXTEND): When a subnormal input produces
	a subnormal result, set the underflow exception if trapping on
	underflow is enabled.
	* soft-fp/soft-fp.h (FP_INIT_TRAPPING_EXCEPTIONS): New macro.
	(FP_INIT_EXCEPTIONS): Default to FP_INIT_TRAPPING_EXCEPTIONS.
	[FP_NO_EXACT_UNDERFLOW] (FP_TRAPPING_EXCEPTIONS): Undefine and
	redefine to 0.
	* soft-fp/extenddftf2.c (FP_NO_EXACT_UNDERFLOW): Define.
	* soft-fp/extendsfdf2.c (FP_NO_EXACT_UNDERFLOW): Likewise.
	* soft-fp/extendsftf2.c (FP_NO_EXACT_UNDERFLOW): Likewise.
	* soft-fp/extendxftf2.c (__extendxftf2): Use
	FP_INIT_TRAPPING_EXCEPTIONS instead of FP_INIT_ROUNDMODE.
2014-10-09 01:00:41 +00:00
Joseph Myers
2d6a47ba4c soft-fp: Remove FP_CLEAR_EXCEPTIONS.
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.
2014-10-09 00:58:42 +00:00