From: "Zhang, Jun"
By test, we find in hybrid platform spincount 1 is better.
Use '-march=native -Ofast -funroll-loops -flto',
results as follows:
spec2017 speed RPL ADL
657.xz_s 0.00% 0.50%
603.bwaves_s 10.90% 26.20%
607.cactuBSSN_s 5.50% 72.50%
619.lbm_s2.40% 2.50%
621.wrf_s-7.70% 2.40%
627.cam4_s 0.50% 0.70%
628.pop2_s 48.20% 153.00%
638.imagick_s-0.10% 0.20%
644.nab_s2.30% 1.40%
649.fotonik3d_s 8.00% 13.80%
654.roms_s 1.20% 1.10%
Geomean-int 0.00% 0.50%
Geomean-fp 6.30% 21.10%
Geomean-all 5.70% 19.10%
omp2012 RPL ADL
350.md -1.81% -1.75%
351.bwaves 7.72% 12.50%
352.nab 14.63% 19.71%
357.bt331-0.20% 1.77%
358.botsalgn 0.00% 0.00%
359.botsspar 0.00% 0.65%
360.ilbdc0.00% 0.25%
362.fma3d2.66% -0.51%
363.swim 10.44% 0.00%
367.imagick 0.00% 0.12%
370.mgrid331 2.49% 25.56%
371.applu331 1.06% 4.22%
372.smithwa 0.74% 3.34%
376.kdtree 10.67% 16.03%
GEOMEAN 3.34% 5.53%
include/ChangeLog:
* spincount.h: New file.
libgomp/ChangeLog:
* env.c (initialize_env): Use do_adjust_default_spincount.
* config/linux/x86/spincount.h: New file.
---
include/spincount.h | 33 +++
libgomp/config/linux/x86/spincount.h | 49
libgomp/env.c| 6 +++-
3 files changed, 87 insertions(+), 1 deletion(-)
create mode 100644 include/spincount.h
create mode 100644 libgomp/config/linux/x86/spincount.h
diff --git a/include/spincount.h b/include/spincount.h
new file mode 100644
index 000..9eecfff198d
--- /dev/null
+++ b/include/spincount.h
@@ -0,0 +1,33 @@
+/* Copyright (C) 2023-2023 Free Software Foundation, Inc.
+ Contributed by Jun Zhang .
+
+ This file is part of the GNU Offloading and Multi Processing Library
+ (libgomp).
+
+ Libgomp is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ Libgomp 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 General Public License for
+ more details.
+
+ Under Section 7 of GPL version 3, you are granted additional
+ permissions described in the GCC Runtime Library Exception, version
+ 3.1, as published by the Free Software Foundation.
+
+ You should have received a copy of the GNU General Public License and
+ a copy of the GCC Runtime Library Exception along with this program;
+ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef GOMP_SPINCOUNT_H
+#define GOMP_SPINCOUNT_H 1
+
+static inline void do_adjust_default_spincount (void)
+{
+}
+
+#endif /* GOMP_SPINCOUNT_H */
diff --git a/libgomp/config/linux/x86/spincount.h
b/libgomp/config/linux/x86/spincount.h
new file mode 100644
index 000..9d2624fd457
--- /dev/null
+++ b/libgomp/config/linux/x86/spincount.h
@@ -0,0 +1,49 @@
+/* Copyright (C) 2023-2023 Free Software Foundation, Inc.
+ Contributed by Jun Zhang .
+
+ This file is part of the GNU Offloading and Multi Processing Library
+ (libgomp).
+
+ Libgomp is free software; you can redistribute it and/or modify it
+ under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3, or (at your option)
+ any later version.
+
+ Libgomp 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 General Public License for
+ more details.
+
+ Under Section 7 of GPL version 3, you are granted additional
+ permissions described in the GCC Runtime Library Exception, version
+ 3.1, as published by the Free Software Foundation.
+
+ You should have received a copy of the GNU General Public License and
+ a copy of the GCC Runtime Library Exception along with this program;
+ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef GOMP_SPINCOUNT_H
+#define GOMP_SPINCOUNT_H 1
+
+#ifdef __x86_64__
+#include "cpuid.h"
+#include "libgomp.h"
+
+/* Only for x86 hybrid platform */
+static inline void do_adjust_default_spincount (void)
+{
+ unsigned int eax, ebx, ecx, edx;
+ if (__get_cpuid_count (7, 0, &eax, &ebx, &ecx, &edx)
+ /* CPUID.07H.0H:EDX[15] Hybrid. */
+ && ((edx >> 15) & 1))
+gomp_spin_count_var = 1LL;
+}
+#else
+
+static inline void do_adjust_default_spincount (void)
+{
