glibc/sysdeps/x86_64/fpu/multiarch/s_roundevenf.c
Shen-Ta Hsieh 1683249d17 x86_64: roundeven with sse4.1 support
This patch adds support for the sse4.1 hardware floating point
roundeven.

Here is some benchmark results on my systems:

=AMD Ryzen 9 3900X 12-Core Processor=

* benchmark result before this commit
|            |    roundeven |   roundevenf |
|------------|--------------|--------------|
| duration   |  3.75587e+09 |  3.75114e+09 |
| iterations |  3.93053e+08 |  4.35402e+08 |
| max        | 52.592       | 58.71        |
| min        |  7.98        |  7.22        |
| mean       |  9.55563     |  8.61535     |

* benchmark result after this commit
|            |     roundeven |   roundevenf |
|------------|---------------|--------------|
| duration   |   3.73815e+09 |  3.73738e+09 |
| iterations |   5.82692e+08 |  5.91498e+08 |
| max        |  56.468       | 51.642       |
| min        |   6.27        |  6.156       |
| mean       |   6.41532     |  6.3185      |

=Intel(R) Pentium(R) CPU D1508 @ 2.20GHz=

* benchmark result before this commit
|            |    roundeven |   roundevenf |
|------------|--------------|--------------|
| duration   |  2.18208e+09 |  2.18258e+09 |
| iterations |  2.39932e+08 |  2.46924e+08 |
| max        | 96.378       | 98.035       |
| min        |  6.776       |  5.94        |
| mean       |  9.09456     |  8.83907     |

* benchmark result after this commit
|            |    roundeven |   roundevenf |
|------------|--------------|--------------|
| duration   |  2.17415e+09 |  2.17005e+09 |
| iterations |  3.56193e+08 |  4.09824e+08 |
| max        | 51.693       | 97.192       |
| min        |  5.926       |  5.093       |
| mean       |  6.10385     |  5.29507     |

Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2021-06-27 07:56:57 -07:00

32 lines
1.1 KiB
C

/* Multiple versions of __roundevenf.
Copyright (C) 2021 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
<https://www.gnu.org/licenses/>. */
#include <libm-alias-float.h>
#define roundevenf __redirect_roundevenf
#define __roundevenf __redirect___roundevenf
#include <math.h>
#undef roundevenf
#undef __roundevenf
#define SYMBOL_NAME roundevenf
#include "ifunc-sse4_1.h"
libc_ifunc_redirected (__redirect_roundevenf, __roundevenf, IFUNC_SELECTOR ());
libm_alias_float (__roundeven, roundeven)