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ax_gcc_x86_avx_xgetbv

Synopsis

AX_GCC_X86_AVX_XGETBV

Description

On later x86 processors with AVX SIMD support, with gcc or a compiler that has a compatible syntax for inline assembly instructions, run a small program that executes the xgetbv instruction with input OP. This can be used to detect if the OS supports AVX instruction usage.

On output, the values of the eax and edx registers are stored as hexadecimal strings as "eax:edx" in the cache variable ax_cv_gcc_x86_avx_xgetbv.

If the xgetbv instruction fails (because you are running a cross-compiler, or because you are not using gcc, or because you are on a processor that doesn’t have this instruction), ax_cv_gcc_x86_avx_xgetbv_OP is set to the string "unknown".

This macro mainly exists to be used in AX_EXT.

Source Code

Download the latest version of ax_gcc_x86_avx_xgetbv.m4 or browse the macro’s revision history.

License

Copyright © 2013 Michael Petch mpetch@capp-sysware.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 3 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 <http://www.gnu.org/licenses/>.

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