1 # =========================================================================== 2 # http://www.gnu.org/software/autoconf-archive/ax_gcc_x86_cpuid.html 3 # =========================================================================== 4 # 5 # SYNOPSIS 6 # 7 # AX_GCC_X86_CPUID(OP) 8 # 9 # DESCRIPTION 10 # 11 # On Pentium and later x86 processors, with gcc or a compiler that has a 12 # compatible syntax for inline assembly instructions, run a small program 13 # that executes the cpuid instruction with input OP. This can be used to 14 # detect the CPU type. 15 # 16 # On output, the values of the eax, ebx, ecx, and edx registers are stored 17 # as hexadecimal strings as "eax:ebx:ecx:edx" in the cache variable 18 # ax_cv_gcc_x86_cpuid_OP. 19 # 20 # If the cpuid instruction fails (because you are running a 21 # cross-compiler, or because you are not using gcc, or because you are on 22 # a processor that doesn't have this instruction), ax_cv_gcc_x86_cpuid_OP 23 # is set to the string "unknown". 24 # 25 # This macro mainly exists to be used in AX_GCC_ARCHFLAG. 26 # 27 # LICENSE 28 # 29 # Copyright (c) 2008 Steven G. Johnson <stevenj (a] alum.mit.edu> 30 # Copyright (c) 2008 Matteo Frigo 31 # 32 # This program is free software: you can redistribute it and/or modify it 33 # under the terms of the GNU General Public License as published by the 34 # Free Software Foundation, either version 3 of the License, or (at your 35 # option) any later version. 36 # 37 # This program is distributed in the hope that it will be useful, but 38 # WITHOUT ANY WARRANTY; without even the implied warranty of 39 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 40 # Public License for more details. 41 # 42 # You should have received a copy of the GNU General Public License along 43 # with this program. If not, see <http://www.gnu.org/licenses/>. 44 # 45 # As a special exception, the respective Autoconf Macro's copyright owner 46 # gives unlimited permission to copy, distribute and modify the configure 47 # scripts that are the output of Autoconf when processing the Macro. You 48 # need not follow the terms of the GNU General Public License when using 49 # or distributing such scripts, even though portions of the text of the 50 # Macro appear in them. The GNU General Public License (GPL) does govern 51 # all other use of the material that constitutes the Autoconf Macro. 52 # 53 # This special exception to the GPL applies to versions of the Autoconf 54 # Macro released by the Autoconf Archive. When you make and distribute a 55 # modified version of the Autoconf Macro, you may extend this special 56 # exception to the GPL to apply to your modified version as well. 57 58 #serial 7 59 60 AC_DEFUN([AX_GCC_X86_CPUID], 61 [AC_REQUIRE([AC_PROG_CC]) 62 AC_LANG_PUSH([C]) 63 AC_CACHE_CHECK(for x86 cpuid $1 output, ax_cv_gcc_x86_cpuid_$1, 64 [AC_RUN_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>], [ 65 int op = $1, eax, ebx, ecx, edx; 66 FILE *f; 67 __asm__("cpuid" 68 : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) 69 : "a" (op)); 70 f = fopen("conftest_cpuid", "w"); if (!f) return 1; 71 fprintf(f, "%x:%x:%x:%x\n", eax, ebx, ecx, edx); 72 fclose(f); 73 return 0; 74 ])], 75 [ax_cv_gcc_x86_cpuid_$1=`cat conftest_cpuid`; rm -f conftest_cpuid], 76 [ax_cv_gcc_x86_cpuid_$1=unknown; rm -f conftest_cpuid], 77 [ax_cv_gcc_x86_cpuid_$1=unknown])]) 78 AC_LANG_POP([C]) 79 ]) 80
