[PATCH] x86_64: Optimize sincos where sin/cos is optimized (bug 29193)
H.J. Lu
hjl.tools@gmail.com
Tue May 31 18:42:43 GMT 2022
On Tue, May 31, 2022 at 9:32 AM Adhemerval Zanella via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
>
>
> On 31/05/2022 10:08, Andreas Schwab via Libc-alpha wrote:
> > The compiler may substitute calls to sin or cos with calls to sincos, thus
> > we should have the same optimized implementations for sincos. The
> > optimized implementations may produce results that differ, that also makes
> > sure that the sincos call aggrees with the sin and cos calls.
>
> LGTM, thanks.
>
> I think we will need to fix for i686 as well, since it provides a
> similar sse2 optimized version.
Since this is an optimization, should we leave i686 alone?
> Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
>
> > ---
> > sysdeps/ieee754/dbl-64/s_sincos.c | 7 +++++
> > sysdeps/x86_64/fpu/multiarch/Makefile | 12 ++++++--
> > sysdeps/x86_64/fpu/multiarch/s_sincos-avx.c | 3 ++
> > sysdeps/x86_64/fpu/multiarch/s_sincos-fma.c | 3 ++
> > sysdeps/x86_64/fpu/multiarch/s_sincos-fma4.c | 3 ++
> > sysdeps/x86_64/fpu/multiarch/s_sincos.c | 30 ++++++++++++++++++++
> > 6 files changed, 55 insertions(+), 3 deletions(-)
> > create mode 100644 sysdeps/x86_64/fpu/multiarch/s_sincos-avx.c
> > create mode 100644 sysdeps/x86_64/fpu/multiarch/s_sincos-fma.c
> > create mode 100644 sysdeps/x86_64/fpu/multiarch/s_sincos-fma4.c
> > create mode 100644 sysdeps/x86_64/fpu/multiarch/s_sincos.c
> >
> > diff --git a/sysdeps/ieee754/dbl-64/s_sincos.c b/sysdeps/ieee754/dbl-64/s_sincos.c
> > index 12c3021e66..890c137ebb 100644
> > --- a/sysdeps/ieee754/dbl-64/s_sincos.c
> > +++ b/sysdeps/ieee754/dbl-64/s_sincos.c
> > @@ -24,10 +24,15 @@
> > #include <math-underflow.h>
> > #include <libm-alias-double.h>
> >
> > +#ifndef SECTION
> > +# define SECTION
> > +#endif
> > +
> > #define IN_SINCOS
> > #include "s_sin.c"
> >
> > void
> > +SECTION
> > __sincos (double x, double *sinx, double *cosx)
> > {
> > mynumber u;
> > @@ -100,4 +105,6 @@ __sincos (double x, double *sinx, double *cosx)
> >
> > *sinx = *cosx = x / x;
> > }
> > +#ifndef __sincos
> > libm_alias_double (__sincos, sincos)
> > +#endif
> > diff --git a/sysdeps/x86_64/fpu/multiarch/Makefile b/sysdeps/x86_64/fpu/multiarch/Makefile
> > index ec796277a5..248162525b 100644
> > --- a/sysdeps/x86_64/fpu/multiarch/Makefile
> > +++ b/sysdeps/x86_64/fpu/multiarch/Makefile
> > @@ -10,7 +10,8 @@ libm-sysdep_routines += s_ceil-sse4_1 s_ceilf-sse4_1 s_floor-sse4_1 \
> > s_trunc-sse4_1 s_truncf-sse4_1
> >
> > libm-sysdep_routines += e_exp-fma e_log-fma e_pow-fma s_atan-fma \
> > - e_asin-fma e_atan2-fma s_sin-fma s_tan-fma
> > + e_asin-fma e_atan2-fma s_sin-fma s_tan-fma \
> > + s_sincos-fma
> >
> > CFLAGS-e_asin-fma.c = -mfma -mavx2
> > CFLAGS-e_atan2-fma.c = -mfma -mavx2
> > @@ -20,6 +21,7 @@ CFLAGS-e_pow-fma.c = -mfma -mavx2
> > CFLAGS-s_atan-fma.c = -mfma -mavx2
> > CFLAGS-s_sin-fma.c = -mfma -mavx2
> > CFLAGS-s_tan-fma.c = -mfma -mavx2
> > +CFLAGS-s_sincos-fma.c = -mfma -mavx2
> >
> > libm-sysdep_routines += s_sinf-sse2 s_cosf-sse2 s_sincosf-sse2
> >
> > @@ -36,7 +38,8 @@ CFLAGS-s_cosf-fma.c = -mfma -mavx2
> > CFLAGS-s_sincosf-fma.c = -mfma -mavx2
> >
> > libm-sysdep_routines += e_exp-fma4 e_log-fma4 e_pow-fma4 s_atan-fma4 \
> > - e_asin-fma4 e_atan2-fma4 s_sin-fma4 s_tan-fma4
> > + e_asin-fma4 e_atan2-fma4 s_sin-fma4 s_tan-fma4 \
> > + s_sincos-fma4
> >
> > CFLAGS-e_asin-fma4.c = -mfma4
> > CFLAGS-e_atan2-fma4.c = -mfma4
> > @@ -46,9 +49,11 @@ CFLAGS-e_pow-fma4.c = -mfma4
> > CFLAGS-s_atan-fma4.c = -mfma4
> > CFLAGS-s_sin-fma4.c = -mfma4
> > CFLAGS-s_tan-fma4.c = -mfma4
> > +CFLAGS-s_sincos-fma4.c = -mfma4
> >
> > libm-sysdep_routines += e_exp-avx e_log-avx s_atan-avx \
> > - e_atan2-avx s_sin-avx s_tan-avx
> > + e_atan2-avx s_sin-avx s_tan-avx \
> > + s_sincos-avx
> >
> > CFLAGS-e_atan2-avx.c = -msse2avx -DSSE2AVX
> > CFLAGS-e_exp-avx.c = -msse2avx -DSSE2AVX
> > @@ -56,6 +61,7 @@ CFLAGS-e_log-avx.c = -msse2avx -DSSE2AVX
> > CFLAGS-s_atan-avx.c = -msse2avx -DSSE2AVX
> > CFLAGS-s_sin-avx.c = -msse2avx -DSSE2AVX
> > CFLAGS-s_tan-avx.c = -msse2avx -DSSE2AVX
> > +CFLAGS-s_sincos-avx.c = -msse2avx -DSSE2AVX
> > endif
> >
> > ifeq ($(subdir),mathvec)
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_sincos-avx.c b/sysdeps/x86_64/fpu/multiarch/s_sincos-avx.c
> > new file mode 100644
> > index 0000000000..debea0f619
> > --- /dev/null
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_sincos-avx.c
> > @@ -0,0 +1,3 @@
> > +#define __sincos __sincos_avx
> > +#define SECTION __attribute__ ((section (".text.avx")))
> > +#include <sysdeps/ieee754/dbl-64/s_sincos.c>
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_sincos-fma.c b/sysdeps/x86_64/fpu/multiarch/s_sincos-fma.c
> > new file mode 100644
> > index 0000000000..31610b3356
> > --- /dev/null
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_sincos-fma.c
> > @@ -0,0 +1,3 @@
> > +#define __sincos __sincos_fma
> > +#define SECTION __attribute__ ((section (".text.fma")))
> > +#include <sysdeps/ieee754/dbl-64/s_sincos.c>
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_sincos-fma4.c b/sysdeps/x86_64/fpu/multiarch/s_sincos-fma4.c
> > new file mode 100644
> > index 0000000000..7e8b8e6484
> > --- /dev/null
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_sincos-fma4.c
> > @@ -0,0 +1,3 @@
> > +#define __sincos __sincos_fma4
> > +#define SECTION __attribute__ ((section (".text.fma4")))
> > +#include <sysdeps/ieee754/dbl-64/s_sincos.c>
> > diff --git a/sysdeps/x86_64/fpu/multiarch/s_sincos.c b/sysdeps/x86_64/fpu/multiarch/s_sincos.c
> > new file mode 100644
> > index 0000000000..67c2817d68
> > --- /dev/null
> > +++ b/sysdeps/x86_64/fpu/multiarch/s_sincos.c
> > @@ -0,0 +1,30 @@
> > +/* Multiple versions of sincos.
> > + Copyright (C) 2017-2022 Free Software Foundation, Inc.
>
> I think it should be only 2022 here.
>
> > + 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
> > + <https://www.gnu.org/licenses/>. */
> > +
> > +#include <libm-alias-double.h>
> > +
> > +extern void __redirect_sincos (double, double *, double *);
> > +
> > +#define SYMBOL_NAME sincos
> > +#include "ifunc-fma4.h"
> > +
> > +libc_ifunc_redirected (__redirect_sincos, __sincos, IFUNC_SELECTOR ());
> > +libm_alias_double (__sincos, sincos)
> > +
> > +#define __sincos __sincos_sse2
> > +#include <sysdeps/ieee754/dbl-64/s_sincos.c>
--
H.J.
More information about the Libc-alpha
mailing list