# =========================================================================== # http://www.gnu.org/software/autoconf-archive/ax_gcc_x86_cpuid.html # =========================================================================== # # SYNOPSIS # # AX_GCC_X86_CPUID(OP) # # DESCRIPTION # # On Pentium and later x86 processors, with gcc or a compiler that has a # compatible syntax for inline assembly instructions, run a small program # that executes the cpuid instruction with input OP. This can be used to # detect the CPU type. # # On output, the values of the eax, ebx, ecx, and edx registers are stored # as hexadecimal strings as "eax:ebx:ecx:edx" in the cache variable # ax_cv_gcc_x86_cpuid_OP. # # If the cpuid 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_cpuid_OP # is set to the string "unknown". # # This macro mainly exists to be used in AX_GCC_ARCHFLAG. # # LICENSE # # Copyright (c) 2008 Steven G. Johnson # Copyright (c) 2008 Matteo Frigo # # 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 . # # As a special exception, the respective Autoconf Macro's copyright owner # gives unlimited permission to copy, distribute and modify the configure # scripts that are the output of Autoconf when processing the Macro. You # need not follow the terms of the GNU General Public License when using # or distributing such scripts, even though portions of the text of the # Macro appear in them. The GNU General Public License (GPL) does govern # all other use of the material that constitutes the Autoconf Macro. # # This special exception to the GPL applies to versions of the Autoconf # Macro released by the Autoconf Archive. When you make and distribute a # modified version of the Autoconf Macro, you may extend this special # exception to the GPL to apply to your modified version as well. #serial 7 AC_DEFUN([AX_GCC_X86_CPUID], [AC_REQUIRE([AC_PROG_CC]) AC_LANG_PUSH([C]) AC_CACHE_CHECK(for x86 cpuid $1 output, ax_cv_gcc_x86_cpuid_$1, [AC_RUN_IFELSE([AC_LANG_PROGRAM([#include ], [ int op = $1, eax, ebx, ecx, edx; FILE *f; __asm__("cpuid" : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) : "a" (op)); f = fopen("conftest_cpuid", "w"); if (!f) return 1; fprintf(f, "%x:%x:%x:%x\n", eax, ebx, ecx, edx); fclose(f); return 0; ])], [ax_cv_gcc_x86_cpuid_$1=`cat conftest_cpuid`; rm -f conftest_cpuid], [ax_cv_gcc_x86_cpuid_$1=unknown; rm -f conftest_cpuid], [ax_cv_gcc_x86_cpuid_$1=unknown])]) AC_LANG_POP([C]) ])