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>

0 files changed, 0 insertions, 0 deletions