diff options
Diffstat (limited to 'm4/ax_gcc_x86_cpuid.m4')
| -rw-r--r-- | m4/ax_gcc_x86_cpuid.m4 | 26 |
1 files changed, 18 insertions, 8 deletions
diff --git a/m4/ax_gcc_x86_cpuid.m4 b/m4/ax_gcc_x86_cpuid.m4 index 7d46fee..df95465 100644 --- a/m4/ax_gcc_x86_cpuid.m4 +++ b/m4/ax_gcc_x86_cpuid.m4 @@ -1,17 +1,19 @@ # =========================================================================== -# http://www.gnu.org/software/autoconf-archive/ax_gcc_x86_cpuid.html +# https://www.gnu.org/software/autoconf-archive/ax_gcc_x86_cpuid.html # =========================================================================== # # SYNOPSIS # # AX_GCC_X86_CPUID(OP) +# AX_GCC_X86_CPUID_COUNT(OP, COUNT) # # 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. +# detect the CPU type. AX_GCC_X86_CPUID_COUNT takes an additional COUNT +# parameter that gets passed into register ECX before calling cpuid. # # 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 @@ -28,6 +30,7 @@ # # Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu> # Copyright (c) 2008 Matteo Frigo +# Copyright (c) 2015 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 @@ -40,7 +43,7 @@ # 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/>. +# with this program. If not, see <https://www.gnu.org/licenses/>. # # As a special exception, the respective Autoconf Macro's copyright owner # gives unlimited permission to copy, distribute and modify the configure @@ -55,18 +58,25 @@ # 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 +#serial 10 AC_DEFUN([AX_GCC_X86_CPUID], +[AX_GCC_X86_CPUID_COUNT($1, 0) +]) + +AC_DEFUN([AX_GCC_X86_CPUID_COUNT], [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 <stdio.h>], [ - int op = $1, eax, ebx, ecx, edx; + int op = $1, level = $2, eax, ebx, ecx, edx; FILE *f; - __asm__("cpuid" - : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) - : "a" (op)); + __asm__ __volatile__ ("xchg %%ebx, %1\n" + "cpuid\n" + "xchg %%ebx, %1\n" + : "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx) + : "a" (op), "2" (level)); + f = fopen("conftest_cpuid", "w"); if (!f) return 1; fprintf(f, "%x:%x:%x:%x\n", eax, ebx, ecx, edx); fclose(f); |