Re: [PATCH 6/6] Add a generic scalb implementation

[Paul E Murphy <murphyp@linux.ibm.com>]

Ping? If no objections/feedback, I will commit with patch 1 in the 
series next week.

Tested on x86_64 and ppc64le.  I've also built/check-abi csky to verify 
the LIBM_SVID_COMPAT changes still generate the appropriate symbols for 
those arches not requiring the compat versions.

On 2/3/20 3:10 PM, Paul E. Murphy wrote:
> From: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
> 
> Create templates for e_scabl and w_scalb.
> ---
>   math/Makefile                              |  7 +--
>   math/{e_scalb.c => e_scalb_template.c}     | 33 ++++++------
>   math/e_scalbf.c                            | 54 --------------------
>   math/e_scalbl.c                            | 54 --------------------
>   math/w_scalb_compat.c                      |  6 +--
>   math/w_scalb_template.c                    | 59 ++++++++++++++++++++++
>   math/w_scalbf_compat.c                     |  4 +-
>   math/w_scalbl_compat.c                     |  4 +-
>   sysdeps/ieee754/float128/w_scalbf128.c     |  1 +
>   sysdeps/ieee754/ldbl-opt/w_scalb_compat.c  |  4 +-
>   sysdeps/ieee754/ldbl-opt/w_scalbl_compat.c |  2 +
>   11 files changed, 91 insertions(+), 137 deletions(-)
>   rename math/{e_scalb.c => e_scalb_template.c} (64%)
>   delete mode 100644 math/e_scalbf.c
>   delete mode 100644 math/e_scalbl.c
>   create mode 100644 math/w_scalb_template.c
>   create mode 100644 sysdeps/ieee754/float128/w_scalbf128.c
> 
> diff --git a/math/Makefile b/math/Makefile
> index 5985b6744b..1d203e7ad5 100644
> --- a/math/Makefile
> +++ b/math/Makefile
> @@ -48,7 +48,7 @@ libm-support = s_lib_version s_matherr s_signgam			\
> 
>   # Wrappers for these functions generated per type using a file named
>   # <func>_template.c and the appropriate math-type-macros-<TYPE>.h.
> -gen-libm-calls = cargF conjF cimagF crealF cabsF s_cacosF		  \
> +gen-libm-calls = cargF conjF cimagF crealF cabsF e_scalbF s_cacosF	  \
>   	         s_cacoshF s_ccosF s_ccoshF s_casinF s_csinF s_casinhF	  \
>   		 k_casinhF s_csinhF k_casinhF s_csinhF s_catanhF s_catanF \
>   		 s_ctanF s_ctanhF s_cexpF s_clogF s_cprojF s_csqrtF	  \
> @@ -58,13 +58,14 @@ gen-libm-calls = cargF conjF cimagF crealF cabsF s_cacosF		  \
>   		 w_log1pF w_scalblnF s_fmaxmagF s_fminmagF w_acosF	  \
>   		 w_acoshF w_asinF w_atan2F w_atanhF w_coshF w_exp10F	  \
>   		 w_exp2F w_fmodF w_hypotF w_j0F w_j1F w_jnF w_logF	  \
> -		 w_log10F w_log2F w_powF w_remainderF w_sinhF w_sqrtF	  \
> +		 w_log10F w_log2F w_powF w_remainderF w_scalbF		  \
> +		 w_sinhF w_sqrtF					  \
>   		 w_tgammaF w_lgammaF w_lgammaF_r w_expF e_exp2F
> 
>   libm-calls =								  \
>   	e_acosF e_acoshF e_asinF e_atan2F e_atanhF e_coshF e_expF e_fmodF \
>   	e_hypotF e_j0F e_j1F e_jnF e_lgammaF_r e_logF e_log10F e_powF	  \
> -	e_remainderF e_scalbF e_sinhF e_sqrtF e_gammaF_r	  \
> +	e_remainderF e_sinhF e_sqrtF e_gammaF_r				  \
>   	e_ilogbF							  \
>   	k_tanF s_asinhF s_atanF s_cbrtF					  \
>   	s_ceilF s_cosF s_erfF s_expm1F s_fabsF				  \
> diff --git a/math/e_scalb.c b/math/e_scalb_template.c
> similarity index 64%
> rename from math/e_scalb.c
> rename to math/e_scalb_template.c
> index dbe3b51d6a..ed0508c7bf 100644
> --- a/math/e_scalb.c
> +++ b/math/e_scalb_template.c
> @@ -1,6 +1,8 @@
> -/* Copyright (C) 2011-2020 Free Software Foundation, Inc.
> +/* Multiply by integral power of radix.
> +
> +   Copyright (C) 2011-2020 Free Software Foundation, Inc.
> +
>      This file is part of the GNU C Library.
> -   Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
> 
>      The GNU C Library is free software; you can redistribute it and/or
>      modify it under the terms of the GNU Lesser General Public
> @@ -20,35 +22,36 @@
>   #include <math_private.h>
>   #include <libm-alias-finite.h>
> 
> -static double
> +static FLOAT
>   __attribute__ ((noinline))
> -invalid_fn (double x, double fn)
> +invalid_fn (FLOAT x, FLOAT fn)
>   {
> -  if (rint (fn) != fn)
> +  if (M_SUF (rint) (fn) != fn)
>       return (fn - fn) / (fn - fn);
> -  else if (fn > 65000.0)
> -    return __scalbn (x, 65000);
> +  else if (fn > M_LIT (65000.0))
> +    return M_SUF (__scalbn) (x, 65000);
>     else
> -    return __scalbn (x,-65000);
> +    return M_SUF (__scalbn) (x,-65000);
>   }
> 
> 
> -double
> -__ieee754_scalb (double x, double fn)
> +FLOAT
> +M_DECL_FUNC (__ieee754_scalb) (FLOAT x, FLOAT fn)
>   {
>     if (__glibc_unlikely (isnan (x)))
>       return x * fn;
>     if (__glibc_unlikely (!isfinite (fn)))
>       {
> -      if (isnan (fn) || fn > 0.0)
> +      if (isnan (fn) || fn > M_LIT (0.0))
>   	return x * fn;
> -      if (x == 0.0)
> +      if (x == M_LIT (0.0))
>   	return x;
>         return x / -fn;
>       }
> -  if (__glibc_unlikely (fabs (fn) >= 0x1p31 || (double) (int) fn != fn))
> +  if (__glibc_unlikely (M_FABS (fn) >= M_LIT (0x1p31)
> +			|| (FLOAT) (int) fn != fn))
>       return invalid_fn (x, fn);
> 
> -  return __scalbn (x, (int) fn);
> +  return M_SCALBN (x, (int) fn);
>   }
> -libm_alias_finite (__ieee754_scalb, __scalb)
> +declare_mgen_finite_alias (__ieee754_scalb, __scalb)
> diff --git a/math/e_scalbf.c b/math/e_scalbf.c
> deleted file mode 100644
> index 944cfbefc9..0000000000
> --- a/math/e_scalbf.c
> +++ /dev/null
> @@ -1,54 +0,0 @@
> -/* Copyright (C) 2011-2020 Free Software Foundation, Inc.
> -   This file is part of the GNU C Library.
> -   Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
> -
> -   The GNU C Library is free software; you can redistribute it and/or
> -   modify it under the terms of the GNU Lesser General Public
> -   License as published by the Free Software Foundation; either
> -   version 2.1 of the License, or (at your option) any later version.
> -
> -   The GNU C Library is distributed in the hope that it will be useful,
> -   but WITHOUT ANY WARRANTY; without even the implied warranty of
> -   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> -   Lesser General Public License for more details.
> -
> -   You should have received a copy of the GNU Lesser General Public
> -   License along with the GNU C Library; if not, see
> -   <https://www.gnu.org/licenses/>.  */
> -
> -#include <math.h>
> -#include <math_private.h>
> -#include <libm-alias-finite.h>
> -
> -static float
> -__attribute__ ((noinline))
> -invalid_fn (float x, float fn)
> -{
> -  if (rintf (fn) != fn)
> -    return (fn - fn) / (fn - fn);
> -  else if (fn > 65000.0f)
> -    return __scalbnf (x, 65000);
> -  else
> -    return __scalbnf (x,-65000);
> -}
> -
> -
> -float
> -__ieee754_scalbf (float x, float fn)
> -{
> -  if (__glibc_unlikely (isnan (x)))
> -    return x * fn;
> -  if (__glibc_unlikely (!isfinite (fn)))
> -    {
> -      if (isnan (fn) || fn > 0.0f)
> -	return x * fn;
> -      if (x == 0.0f)
> -	return x;
> -      return x / -fn;
> -    }
> -  if (__glibc_unlikely (fabsf (fn) >= 0x1p31f || (float) (int) fn != fn))
> -    return invalid_fn (x, fn);
> -
> -  return __scalbnf (x, (int) fn);
> -}
> -libm_alias_finite (__ieee754_scalbf, __scalbf)
> diff --git a/math/e_scalbl.c b/math/e_scalbl.c
> deleted file mode 100644
> index 6595ec6c27..0000000000
> --- a/math/e_scalbl.c
> +++ /dev/null
> @@ -1,54 +0,0 @@
> -/* Copyright (C) 2011-2020 Free Software Foundation, Inc.
> -   This file is part of the GNU C Library.
> -   Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
> -
> -   The GNU C Library is free software; you can redistribute it and/or
> -   modify it under the terms of the GNU Lesser General Public
> -   License as published by the Free Software Foundation; either
> -   version 2.1 of the License, or (at your option) any later version.
> -
> -   The GNU C Library is distributed in the hope that it will be useful,
> -   but WITHOUT ANY WARRANTY; without even the implied warranty of
> -   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> -   Lesser General Public License for more details.
> -
> -   You should have received a copy of the GNU Lesser General Public
> -   License along with the GNU C Library; if not, see
> -   <https://www.gnu.org/licenses/>.  */
> -
> -#include <math.h>
> -#include <math_private.h>
> -#include <libm-alias-finite.h>
> -
> -static long double
> -__attribute__ ((noinline))
> -invalid_fn (long double x, long double fn)
> -{
> -  if (rintl (fn) != fn)
> -    return (fn - fn) / (fn - fn);
> -  else if (fn > 65000.0L)
> -    return __scalbnl (x, 65000);
> -  else
> -    return __scalbnl (x,-65000);
> -}
> -
> -
> -long double
> -__ieee754_scalbl (long double x, long double fn)
> -{
> -  if (__glibc_unlikely (isnan (x)))
> -    return x * fn;
> -  if (__glibc_unlikely (!isfinite (fn)))
> -    {
> -      if (isnan (fn) || fn > 0.0L)
> -	return x * fn;
> -      if (x == 0.0L)
> -	return x;
> -      return x / -fn;
> -    }
> -  if (__glibc_unlikely (fabsl (fn) >= 0x1p31L || (long double) (int) fn != fn))
> -    return invalid_fn (x, fn);
> -
> -  return __scalbnl (x, (int) fn);
> -}
> -libm_alias_finite (__ieee754_scalbl, __scalbl)
> diff --git a/math/w_scalb_compat.c b/math/w_scalb_compat.c
> index c3dd3db4f7..664c0474a7 100644
> --- a/math/w_scalb_compat.c
> +++ b/math/w_scalb_compat.c
> @@ -41,18 +41,15 @@ sysv_scalb (double x, double fn)
> 
>     return z;
>   }
> -#endif
> 
> 
>   /* Wrapper scalb */
>   double
>   __scalb (double x, double fn)
>   {
> -#if LIBM_SVID_COMPAT
>     if (__glibc_unlikely (_LIB_VERSION == _SVID_))
>       return sysv_scalb (x, fn);
>     else
> -#endif
>       {
>         double z = __ieee754_scalb (x, fn);
> 
> @@ -79,7 +76,8 @@ __scalb (double x, double fn)
>       }
>   }
>   weak_alias (__scalb, scalb)
> -#ifdef NO_LONG_DOUBLE
> +# ifdef NO_LONG_DOUBLE
>   strong_alias (__scalb, __scalbl)
>   weak_alias (__scalb, scalbl)
> +# endif
>   #endif
> diff --git a/math/w_scalb_template.c b/math/w_scalb_template.c
> new file mode 100644
> index 0000000000..b2aafcdf36
> --- /dev/null
> +++ b/math/w_scalb_template.c
> @@ -0,0 +1,59 @@
> +/* Wrapper to set errno for scalb.
> +   Copyright (C) 2018 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <http://www.gnu.org/licenses/>.  */
> +
> +/* Only build wrappers from the templates for the types that define the macro
> +   below.  This macro is set in math-type-macros-<type>.h in sysdeps/generic
> +   for each floating-point type.  */
> +#if __USE_WRAPPER_TEMPLATE
> +
> +#include <errno.h>
> +#include <math.h>
> +#include <math_private.h>
> +
> +/* Wrapper scalb */
> +FLOAT
> +M_DECL_FUNC (__scalb) (FLOAT x, FLOAT fn)
> +{
> +    {
> +      FLOAT z = M_SUF (__ieee754_scalb) (x, fn);
> +
> +      if (__glibc_unlikely (!isfinite (z) || z == M_LIT (0.0)))
> +	{
> +	  if (isnan (z))
> +	    {
> +	      if (!isnan (x) && !isnan (fn))
> +		__set_errno (EDOM);
> +	    }
> +	  else if (isinf (z))
> +	    {
> +	      if (!isinf (x) && !isinf (fn))
> +		__set_errno (ERANGE);
> +	    }
> +	  else
> +	    {
> +	      /* z == 0.  */
> +	      if (x != M_LIT (0.0) && !isinf (fn))
> +		__set_errno (ERANGE);
> +	    }
> +	}
> +      return z;
> +    }
> +}
> +declare_mgen_alias (__scalb, scalb);
> +
> +#endif /* __USE_WRAPPER_TEMPLATE.  */
> diff --git a/math/w_scalbf_compat.c b/math/w_scalbf_compat.c
> index 42bba44cc6..1b742e9b98 100644
> --- a/math/w_scalbf_compat.c
> +++ b/math/w_scalbf_compat.c
> @@ -41,18 +41,15 @@ sysv_scalbf (float x, float fn)
> 
>     return z;
>   }
> -#endif
> 
> 
>   /* Wrapper scalbf */
>   float
>   __scalbf (float x, float fn)
>   {
> -#if LIBM_SVID_COMPAT
>     if (__glibc_unlikely (_LIB_VERSION == _SVID_))
>       return sysv_scalbf (x, fn);
>     else
> -#endif
>       {
>         float z = __ieee754_scalbf (x, fn);
> 
> @@ -79,3 +76,4 @@ __scalbf (float x, float fn)
>       }
>   }
>   weak_alias (__scalbf, scalbf)
> +#endif
> diff --git a/math/w_scalbl_compat.c b/math/w_scalbl_compat.c
> index 8858c6b66d..c8ba3fddb4 100644
> --- a/math/w_scalbl_compat.c
> +++ b/math/w_scalbl_compat.c
> @@ -41,18 +41,15 @@ sysv_scalbl (long double x, long double fn)
> 
>     return z;
>   }
> -#endif
> 
> 
>   /* Wrapper scalbl */
>   long double
>   __scalbl (long double x, long double fn)
>   {
> -#if LIBM_SVID_COMPAT
>     if (__glibc_unlikely (_LIB_VERSION == _SVID_))
>       return sysv_scalbl (x, fn);
>     else
> -#endif
>       {
>         long double z = __ieee754_scalbl (x, fn);
> 
> @@ -79,3 +76,4 @@ __scalbl (long double x, long double fn)
>       }
>   }
>   weak_alias (__scalbl, scalbl)
> +#endif
> diff --git a/sysdeps/ieee754/float128/w_scalbf128.c b/sysdeps/ieee754/float128/w_scalbf128.c
> new file mode 100644
> index 0000000000..067b724164
> --- /dev/null
> +++ b/sysdeps/ieee754/float128/w_scalbf128.c
> @@ -0,0 +1 @@
> +/* Not defined for _FloatN types.  */
> diff --git a/sysdeps/ieee754/ldbl-opt/w_scalb_compat.c b/sysdeps/ieee754/ldbl-opt/w_scalb_compat.c
> index f6d53a5ba5..56735e825e 100644
> --- a/sysdeps/ieee754/ldbl-opt/w_scalb_compat.c
> +++ b/sysdeps/ieee754/ldbl-opt/w_scalb_compat.c
> @@ -1,5 +1,7 @@
>   #include <math_ldbl_opt.h>
>   #include <math/w_scalb_compat.c>
> -#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
> +#if LIBM_SVID_COMPAT
> +# if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
>   compat_symbol (libm, __scalb, scalbl, GLIBC_2_0);
> +# endif
>   #endif
> diff --git a/sysdeps/ieee754/ldbl-opt/w_scalbl_compat.c b/sysdeps/ieee754/ldbl-opt/w_scalbl_compat.c
> index c8feb654a2..4d16f413c4 100644
> --- a/sysdeps/ieee754/ldbl-opt/w_scalbl_compat.c
> +++ b/sysdeps/ieee754/ldbl-opt/w_scalbl_compat.c
> @@ -2,4 +2,6 @@
>   #undef weak_alias
>   #define weak_alias(n,a)
>   #include <math/w_scalbl_compat.c>
> +#if LIBM_SVID_COMPAT
>   long_double_symbol (libm, __scalbl, scalbl);
> +#endif
>