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ax_gcc_x86_cpu_supports

Synopsis

AX_GCC_X86_CPU_SUPPORTS(X86-INSTRUCTION-SET,
  [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])

Description

Checks if the host cpu supports X86-INSTRUCTION-SET. The instruction set that can be tested are "mmx, popcnt, sse, sse2, sse3, sse4.1, sse4.2, sse4a, avx, avx2, avx512f, fma, fma4, bmi, bmi2". If the instruction set is supported by the host cpu, the C preprocessor macro HAVE_XXX_INSTRUCTIONS is set to 1. The XXX is up-cased instruction case with dot replaced by underscore. For example, the test for "sse4.2" would export HAVE_SSE4_2_INSTRUCTIONS=1. This macro requires gcc extended builtin function "__builtin_cpu_init" and "__builtin_cpu_supports" to detect the cpu features. It will error out if the compiler doesn’t has these builtins.

If the test for the instruction set succeeded, the hook ACTION-IF-FOUND would run. Otherwise the hook ACTION-IF-NOT-FOUND would run if specified.

See also AX_CHECK_X86_FEATURES, which checks all the possible instruction set and export the corresponding CFLAGS.

Source Code

Download the latest version of ax_gcc_x86_cpu_supports.m4 or browse the macro’s revision history.

License

Copyright © 2016 Felix Chern idryman@gmail.com

This program 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 2 of the License, or (at your option) any later version.

This program 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.

You should have received a copy of the GNU General Public License along with this program. If not, see <https://www.gnu.org/licenses/>.

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