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>
(cherry picked from commit 1683249d17e14827b6579529742eb895027dfa84)

7 files changed, 118 insertions, 2 deletions

diff --git a/sysdeps/x86_64/fpu/multiarch/Makefile b/sysdeps/x86_64/fpu/multiarch/Makefile
index 3836574f48..7e3a3f78cb 100644
--- a/sysdeps/x86_64/fpu/multiarch/Makefile
+++ b/sysdeps/x86_64/fpu/multiarch/Makefile
@@ -1,11 +1,12 @@
 ifeq ($(subdir),math)
 libm-sysdep_routines += s_floor-c s_ceil-c s_floorf-c s_ceilf-c \
 			s_rint-c s_rintf-c s_nearbyint-c s_nearbyintf-c \
-			s_trunc-c s_truncf-c
+			s_roundeven-c s_roundevenf-c s_trunc-c s_truncf-c
 
 libm-sysdep_routines += s_ceil-sse4_1 s_ceilf-sse4_1 s_floor-sse4_1 \
 			s_floorf-sse4_1 s_nearbyint-sse4_1 \
-			s_nearbyintf-sse4_1 s_rint-sse4_1 s_rintf-sse4_1 \
+			s_nearbyintf-sse4_1 s_roundeven-sse4_1 \
+			s_roundevenf-sse4_1 s_rint-sse4_1 s_rintf-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 \
diff --git a/sysdeps/x86_64/fpu/multiarch/s_roundeven-c.c b/sysdeps/x86_64/fpu/multiarch/s_roundeven-c.c
new file mode 100644
index 0000000000..c7be43cb22
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/s_roundeven-c.c
@@ -0,0 +1,2 @@
+#define __roundeven __roundeven_c
+#include <sysdeps/ieee754/dbl-64/s_roundeven.c>
diff --git a/sysdeps/x86_64/fpu/multiarch/s_roundeven-sse4_1.S b/sysdeps/x86_64/fpu/multiarch/s_roundeven-sse4_1.S
new file mode 100644
index 0000000000..6ae8f6b1d3
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/s_roundeven-sse4_1.S
@@ -0,0 +1,24 @@
+/* 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 <sysdep.h>
+
+	.section .text.sse4.1,"ax",@progbits
+ENTRY(__roundeven_sse41)
+	roundsd	$8, %xmm0, %xmm0
+	ret
+END(__roundeven_sse41)
diff --git a/sysdeps/x86_64/fpu/multiarch/s_roundeven.c b/sysdeps/x86_64/fpu/multiarch/s_roundeven.c
new file mode 100644
index 0000000000..d92eda652a
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/s_roundeven.c
@@ -0,0 +1,31 @@
+/* Multiple versions of __roundeven.
+   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-double.h>
+
+#define roundeven __redirect_roundeven
+#define __roundeven __redirect___roundeven
+#include <math.h>
+#undef roundeven
+#undef __roundeven
+
+#define SYMBOL_NAME roundeven
+#include "ifunc-sse4_1.h"
+
+libc_ifunc_redirected (__redirect_roundeven, __roundeven, IFUNC_SELECTOR ());
+libm_alias_double (__roundeven, roundeven)
diff --git a/sysdeps/x86_64/fpu/multiarch/s_roundevenf-c.c b/sysdeps/x86_64/fpu/multiarch/s_roundevenf-c.c
new file mode 100644
index 0000000000..72a6e7d1fb
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/s_roundevenf-c.c
@@ -0,0 +1,3 @@
+#undef __roundevenf
+#define __roundevenf __roundevenf_c
+#include <sysdeps/ieee754/flt-32/s_roundevenf.c>
diff --git a/sysdeps/x86_64/fpu/multiarch/s_roundevenf-sse4_1.S b/sysdeps/x86_64/fpu/multiarch/s_roundevenf-sse4_1.S
new file mode 100644
index 0000000000..a76e10807e
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/s_roundevenf-sse4_1.S
@@ -0,0 +1,24 @@
+/* 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 <sysdep.h>
+
+	.section .text.sse4.1,"ax",@progbits
+ENTRY(__roundevenf_sse41)
+	roundss	$8, %xmm0, %xmm0
+	ret
+END(__roundevenf_sse41)
diff --git a/sysdeps/x86_64/fpu/multiarch/s_roundevenf.c b/sysdeps/x86_64/fpu/multiarch/s_roundevenf.c
new file mode 100644
index 0000000000..2ee196e68f
--- /dev/null
+++ b/sysdeps/x86_64/fpu/multiarch/s_roundevenf.c
@@ -0,0 +1,31 @@
+/* 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)