| /* Initialize CPU feature data. |
| This file is part of the GNU C Library. |
| Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc. |
| Contributed by Ulrich Drepper <drepper@redhat.com>. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <atomic.h> |
| #include <cpuid.h> |
| #include "init-arch.h" |
| |
| |
| struct cpu_features __cpu_features attribute_hidden; |
| |
| |
| static void |
| get_common_indeces (unsigned int *family, unsigned int *model) |
| { |
| __cpuid (1, __cpu_features.cpuid[COMMON_CPUID_INDEX_1].eax, |
| __cpu_features.cpuid[COMMON_CPUID_INDEX_1].ebx, |
| __cpu_features.cpuid[COMMON_CPUID_INDEX_1].ecx, |
| __cpu_features.cpuid[COMMON_CPUID_INDEX_1].edx); |
| |
| unsigned int eax = __cpu_features.cpuid[COMMON_CPUID_INDEX_1].eax; |
| *family = (eax >> 8) & 0x0f; |
| *model = (eax >> 4) & 0x0f; |
| } |
| |
| |
| void |
| __init_cpu_features (void) |
| { |
| unsigned int ebx; |
| unsigned int ecx; |
| unsigned int edx; |
| unsigned int family = 0; |
| unsigned int model = 0; |
| enum cpu_features_kind kind; |
| |
| __cpuid (0, __cpu_features.max_cpuid, ebx, ecx, edx); |
| |
| /* This spells out "GenuineIntel". */ |
| if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69) |
| { |
| kind = arch_kind_intel; |
| |
| get_common_indeces (&family, &model); |
| |
| /* Intel processors prefer SSE instruction for memory/string |
| routines if they are avaiable. */ |
| __cpu_features.feature[index_Prefer_SSE_for_memop] |
| |= bit_Prefer_SSE_for_memop; |
| |
| unsigned int eax = __cpu_features.cpuid[COMMON_CPUID_INDEX_1].eax; |
| unsigned int extended_family = (eax >> 20) & 0xff; |
| unsigned int extended_model = (eax >> 12) & 0xf0; |
| if (family == 0x0f) |
| { |
| family += extended_family; |
| model += extended_model; |
| } |
| else if (family == 0x06) |
| { |
| model += extended_model; |
| switch (model) |
| { |
| case 0x1c: |
| case 0x26: |
| /* BSF is slow on Atom. */ |
| __cpu_features.feature[index_Slow_BSF] |= bit_Slow_BSF; |
| break; |
| |
| case 0x1a: |
| case 0x1e: |
| case 0x1f: |
| case 0x25: |
| case 0x2c: |
| case 0x2e: |
| case 0x2f: |
| /* Rep string instructions and copy backward are fast on |
| Intel Core i3, i5 and i7. */ |
| #if index_Fast_Rep_String != index_Fast_Copy_Backward |
| # error index_Fast_Rep_String != index_Fast_Copy_Backward |
| #endif |
| __cpu_features.feature[index_Fast_Rep_String] |
| |= bit_Fast_Rep_String | bit_Fast_Copy_Backward; |
| break; |
| } |
| } |
| } |
| /* This spells out "AuthenticAMD". */ |
| else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65) |
| { |
| kind = arch_kind_amd; |
| |
| get_common_indeces (&family, &model); |
| } |
| else |
| kind = arch_kind_other; |
| |
| __cpu_features.family = family; |
| __cpu_features.model = model; |
| atomic_write_barrier (); |
| __cpu_features.kind = kind; |
| } |
| |
| #undef __get_cpu_features |
| |
| const struct cpu_features * |
| __get_cpu_features (void) |
| { |
| if (__cpu_features.kind == arch_kind_unknown) |
| __init_cpu_features (); |
| |
| return &__cpu_features; |
| } |