From 24a2e6588d2e0c91b4003878b0625d4a9360e8f3 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Wed, 16 Aug 2017 08:43:35 -0700 Subject: x86-64: Optimize e_expf with FMA [BZ #21912] FMA optimized e_expf improves performance by more than 50% on Skylake. [BZ #21912] * sysdeps/x86_64/fpu/multiarch/Makefile (libm-sysdep_routines): Add e_expf-fma. * sysdeps/x86_64/fpu/multiarch/e_expf-fma.S: New file. * sysdeps/x86_64/fpu/multiarch/e_expf.c: Likewise. * sysdeps/x86_64/fpu/multiarch/ifunc-fma.h: Likewise. --- sysdeps/x86_64/fpu/multiarch/ifunc-fma.h | 34 ++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 sysdeps/x86_64/fpu/multiarch/ifunc-fma.h (limited to 'sysdeps/x86_64/fpu/multiarch/ifunc-fma.h') diff --git a/sysdeps/x86_64/fpu/multiarch/ifunc-fma.h b/sysdeps/x86_64/fpu/multiarch/ifunc-fma.h new file mode 100644 index 0000000000..383c41ffb1 --- /dev/null +++ b/sysdeps/x86_64/fpu/multiarch/ifunc-fma.h @@ -0,0 +1,34 @@ +/* Common definition for ifunc selections optimized with AVX2/FMA. + Copyright (C) 2017 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 + . */ + +#include + +extern __typeof (REDIRECT_NAME) OPTIMIZE (sse2) attribute_hidden; +extern __typeof (REDIRECT_NAME) OPTIMIZE (fma) attribute_hidden; + +static inline void * +IFUNC_SELECTOR (void) +{ + const struct cpu_features* cpu_features = __get_cpu_features (); + + if (CPU_FEATURES_ARCH_P (cpu_features, FMA_Usable) + && CPU_FEATURES_ARCH_P (cpu_features, AVX2_Usable)) + return OPTIMIZE (fma); + + return OPTIMIZE (sse2); +} -- cgit v1.2.3