| Message ID | 20210304150057.14418-1-rzinsly@linux.ibm.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v3,1/3] powerpc: Add optimized ilogb* for POWER9 | expand |
On 3/4/21 9:00 AM, Raphael Moreira Zinsly wrote: > Changes since v2: > - Moved the GCC version test to math_private.h and start using > __has_builtin(). > - Removed the optimization from long double as it was converting > ibm128 to float128. > > ---8<--- > > The instructions xsxexpdp and xsxexpqp introduced on POWER9 extract > the exponent from a double-precision and quad-precision floating-point > respectively, thus they can be used to improve ilogb, ilogbf and ilogbf128. > --- > sysdeps/powerpc/fpu/math_private.h | 26 +++++++++++++++- > .../powerpc64/le/fpu/w_ilogb_template.c | 30 +++++++++++++++++++ > sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c | 3 ++ > 3 files changed, 58 insertions(+), 1 deletion(-) > create mode 100644 sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c > create mode 100644 sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c > > diff --git a/sysdeps/powerpc/fpu/math_private.h b/sysdeps/powerpc/fpu/math_private.h > index 91b1361749..21628f3bda 100644 > --- a/sysdeps/powerpc/fpu/math_private.h > +++ b/sysdeps/powerpc/fpu/math_private.h > @@ -25,7 +25,28 @@ > > #include_next <math_private.h> > > -#if defined _ARCH_PWR9 && __HAVE_DISTINCT_FLOAT128 > +#ifdef _ARCH_PWR9 > + > +#if __GNUC_PREREQ (8, 0) > +# define _GL_HAS_BUILTIN_ILOGB 1 > +#elif defined __has_builtin > +# define _GL_HAS_BUILTIN_ILOGB __has_builtin (__builtin_vsx_scalar_extract_exp) > +#else > +# define _GL_HAS_BUILTIN_ILOGB 0 > +#endif > + > +#define __builtin_test_dc_ilogbf __builtin_test_dc_ilogb > +#define __builtin_ilogbf __builtin_ilogb > + > +#define __builtin_test_dc_ilogb(x, y) \ > + __builtin_vsx_scalar_test_data_class_dp(x, y) > +#define __builtin_ilogb(x) __builtin_vsx_scalar_extract_exp(x) - 0x3ff > + > +#define __builtin_test_dc_ilogbf128(x, y) \ > + __builtin_vsx_scalar_test_data_class_qp(x, y) > +#define __builtin_ilogbf128(x) __builtin_vsx_scalar_extract_expq(x) - 0x3fff > + > +#if __HAVE_DISTINCT_FLOAT128 > extern __always_inline _Float128 > __ieee754_sqrtf128 (_Float128 __x) > { > @@ -34,5 +55,8 @@ __ieee754_sqrtf128 (_Float128 __x) > return __z; > } > #endif > +#else /* !_ARCH_PWR9 */ > +#define _GL_HAS_BUILTIN_ILOGB 0 > +#endif > > #endif /* _PPC_MATH_PRIVATE_H_ */ > diff --git a/sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c > new file mode 100644 > index 0000000000..b5c1c0aa9d > --- /dev/null > +++ b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c > @@ -0,0 +1,30 @@ > +#include <math.h> > +#include <errno.h> > +#include <limits.h> > +#include <math_private.h> > +#include <fenv.h> > + > +#if _GL_HAS_BUILTIN_ILOGB > +int > +M_DECL_FUNC (__ilogb) (FLOAT x) > +{ > + int r; > + /* Check for exceptional cases. */ > + if (! M_SUF(__builtin_test_dc_ilogb) (x, 0x7f)) > + r = M_SUF (__builtin_ilogb) (x); > + else > + /* Fallback to the generic ilogb if x is NaN, Inf or subnormal. */ > + r = M_SUF (__ieee754_ilogb) (x); > + if (__builtin_expect (r == FP_ILOGB0, 0) > + || __builtin_expect (r == FP_ILOGBNAN, 0) > + || __builtin_expect (r == INT_MAX, 0)) > + { > + __set_errno (EDOM); > + __feraiseexcept (FE_INVALID); > + } > + return r; > +} > +declare_mgen_alias (__ilogb, ilogb) > +#else > +#include <math/w_ilogb_template.c> > +#endif > diff --git a/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c > new file mode 100644 > index 0000000000..215a00141d > --- /dev/null > +++ b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c > @@ -0,0 +1,3 @@ > +/* Skip the optimization for long double as it uses ibm128. */ I would recommend rewording this as "... as ibm128 does not provide an optimized builtin". Though, I suspect you could use the double version of these built-ins by extracting the significant double of the ibm128, and testing/extracting it in a similar manner. Anyhow, this patch is OK with a minor rewording of this comment. > +#include <math-type-macros-ldouble.h> > +#include <math/w_ilogb_template.c> >
On 04/03/2021 12:30, Paul E Murphy wrote: > >> diff --git a/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c >> b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c >> new file mode 100644 >> index 0000000000..215a00141d >> --- /dev/null >> +++ b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c >> @@ -0,0 +1,3 @@ >> +/* Skip the optimization for long double as it uses ibm128. */ > > I would recommend rewording this as "... as ibm128 does not provide an > optimized builtin". > > Though, I suspect you could use the double version of these built-ins by > extracting the significant double of the ibm128, and testing/extracting > it in a similar manner. > > Anyhow, this patch is OK with a minor rewording of this comment. > I fixed that and pushed as 56c81132ccc6f468fa4fc29c536db060e18e9d87, thanks! Best Regards,
diff --git a/sysdeps/powerpc/fpu/math_private.h b/sysdeps/powerpc/fpu/math_private.h index 91b1361749..21628f3bda 100644 --- a/sysdeps/powerpc/fpu/math_private.h +++ b/sysdeps/powerpc/fpu/math_private.h @@ -25,7 +25,28 @@ #include_next <math_private.h> -#if defined _ARCH_PWR9 && __HAVE_DISTINCT_FLOAT128 +#ifdef _ARCH_PWR9 + +#if __GNUC_PREREQ (8, 0) +# define _GL_HAS_BUILTIN_ILOGB 1 +#elif defined __has_builtin +# define _GL_HAS_BUILTIN_ILOGB __has_builtin (__builtin_vsx_scalar_extract_exp) +#else +# define _GL_HAS_BUILTIN_ILOGB 0 +#endif + +#define __builtin_test_dc_ilogbf __builtin_test_dc_ilogb +#define __builtin_ilogbf __builtin_ilogb + +#define __builtin_test_dc_ilogb(x, y) \ + __builtin_vsx_scalar_test_data_class_dp(x, y) +#define __builtin_ilogb(x) __builtin_vsx_scalar_extract_exp(x) - 0x3ff + +#define __builtin_test_dc_ilogbf128(x, y) \ + __builtin_vsx_scalar_test_data_class_qp(x, y) +#define __builtin_ilogbf128(x) __builtin_vsx_scalar_extract_expq(x) - 0x3fff + +#if __HAVE_DISTINCT_FLOAT128 extern __always_inline _Float128 __ieee754_sqrtf128 (_Float128 __x) { @@ -34,5 +55,8 @@ __ieee754_sqrtf128 (_Float128 __x) return __z; } #endif +#else /* !_ARCH_PWR9 */ +#define _GL_HAS_BUILTIN_ILOGB 0 +#endif #endif /* _PPC_MATH_PRIVATE_H_ */ diff --git a/sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c new file mode 100644 index 0000000000..b5c1c0aa9d --- /dev/null +++ b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogb_template.c @@ -0,0 +1,30 @@ +#include <math.h> +#include <errno.h> +#include <limits.h> +#include <math_private.h> +#include <fenv.h> + +#if _GL_HAS_BUILTIN_ILOGB +int +M_DECL_FUNC (__ilogb) (FLOAT x) +{ + int r; + /* Check for exceptional cases. */ + if (! M_SUF(__builtin_test_dc_ilogb) (x, 0x7f)) + r = M_SUF (__builtin_ilogb) (x); + else + /* Fallback to the generic ilogb if x is NaN, Inf or subnormal. */ + r = M_SUF (__ieee754_ilogb) (x); + if (__builtin_expect (r == FP_ILOGB0, 0) + || __builtin_expect (r == FP_ILOGBNAN, 0) + || __builtin_expect (r == INT_MAX, 0)) + { + __set_errno (EDOM); + __feraiseexcept (FE_INVALID); + } + return r; +} +declare_mgen_alias (__ilogb, ilogb) +#else +#include <math/w_ilogb_template.c> +#endif diff --git a/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c new file mode 100644 index 0000000000..215a00141d --- /dev/null +++ b/sysdeps/powerpc/powerpc64/le/fpu/w_ilogbl.c @@ -0,0 +1,3 @@ +/* Skip the optimization for long double as it uses ibm128. */ +#include <math-type-macros-ldouble.h> +#include <math/w_ilogb_template.c>