Continuing the process of setting up common macros for libm function
aliases, with a view to using them to define _FloatN / _FloatNx
aliases in future, this patch adds a libm_alias_double macro and uses
it in the type-generic templates.
This macro handles defining aliases for double, and for long double in
the NO_LONG_DOUBLE case. It also handles defining compat symbols for
long double = double for architectures that changed their long double
format. By so doing, it eliminates the need for the
M_LIBM_NEED_COMPAT and declare_mgen_libm_compat macros; the single
declare_mgen_alias call in each template now suffices to define all
required compat symbols. When used for more double functions (not
based on type-generic templates), I expect it will eliminate the need
for most ldbl-opt wrappers for such functions.
A few special cases are needed. __clog10l is a public symbol (for
historical reasons) so needs to be given appropriate compat versions
for architectures that changed their long double format, but is not
defined as an alias using the normal macros since __clog10* are *not*
public symbols for _FloatN / _FloatNx types. For scalbn, scalbln and
log1p, the changes adding errno setting support for those functions
left compat symbols pointing directly to the non-errno-setting
implementations. There is no requirement for the compat symbols not
to set errno; that just made for the simplest patches at that time.
Now, with these common macros, it's natural to redirect the compat
symbols to the errno-setting wrappers, which I intend to do in a
separate patch.
Tested for x86_64, and with build-many-glibcs.py. For ldbl-opt
platforms the stripped libm.so binaries are changed (disassembly
unchanged) because the details of how the clog10l compat symbol is
created mean it ceases to be weak as it was before; for other
platforms, stripped libm.so binaries are unchanged.
2017-09-13 Joseph Myers <joseph@codesourcery.com>
* sysdeps/generic/libm-alias-double.h: New file.
* sysdeps/ieee754/ldbl-opt/libm-alias-double.h: Likewise.
* sysdeps/generic/math-type-macros-double.h: Include
<libm-alias-double.h>.
[declare_mgen_alias] (declare_mgen_alias): Define to use
libm_alias_double.
* sysdeps/generic/math-type-macros.h [!M_LIBM_NEED_COMPAT]
(M_LIBM_NEED_COMPAT): Remove macro.
[!M_LIBM_NEED_COMPAT] (declare_mgen_libm_compat): Likewise.
* sysdeps/ieee754/ldbl-opt/math-type-macros-double.h: Remove.
* math/cabs_template.c [M_LIBM_NEED_COMPAT]: Remove conditional
code.
* math/carg_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/cimag_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/conj_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/creal_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_cacos_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_cacosh_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_casin_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_casinh_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_catan_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_catanh_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_ccos_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_ccosh_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_cexp_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_clog10_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_clog_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_cpow_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_cproj_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_csin_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_csinh_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_csqrt_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_ctan_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_ctanh_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_fdim_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_fmax_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_fmin_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/s_nan_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* math/w_ilogb_template.c [M_LIBM_NEED_COMPAT]: Likewise.
* sysdeps/ieee754/ldbl-opt/s_clog10.c: New file.
* sysdeps/ieee754/ldbl-opt/s_ldexp.c (M_LIBM_NEED_COMPAT): Remove
macro.
(declare_mgen_alias): New macro.
* sysdeps/ieee754/ldbl-opt/w_log1p.c: New file.
* sysdeps/ieee754/ldbl-opt/w_scalbln.c: Likewise.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c
(M_LIBM_NEED_COMPAT): Remove macro.
* sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c
[HAVE_AS_VIS3_SUPPORT]: Include <math_ldbl_opt.h> and
<first-versions.h>.
[HAVE_AS_VIS3_SUPPORT && LONG_DOUBLE_COMPAT (libm,
FIRST_VERSION_libm_fdiml)]: Define fdiml as compat symbol.
This defines a new classes of libm objects. The
<func>_template.c file which is used in conjunction
with the new makefile hooks to derive variants for
each type supported by the target machine.
The headers math-type-macros-TYPE.h are used to supply
macros to a common implementation of a function in
a file named FUNC_template.c and glued togethor via
a generated file matching existing naming in the
build directory.
This has the properties of preserving the existing
override mechanism and not requiring any arcane
build system twiddling. Likewise, it enables machines
to override these files without any additional work.
I have verified the built objects for ppc64, x86_64,
alpha, arm, and m68k do not change in any meaningful
way with these changes using the Fedora cross toolchains.
I have verified the x86_64 and ppc64 changes still run.
