1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "base/cpu.h"
6
7#if defined(ARCH_CPU_X86_FAMILY)
8#if defined(_MSC_VER)
9#include <intrin.h>
10#endif
11#endif
12
13#include <string.h>
14
15namespace base {
16
17CPU::CPU()
18  : type_(0),
19    family_(0),
20    model_(0),
21    stepping_(0),
22    ext_model_(0),
23    ext_family_(0),
24    has_mmx_(false),
25    has_sse_(false),
26    has_sse2_(false),
27    has_sse3_(false),
28    has_ssse3_(false),
29    has_sse41_(false),
30    has_sse42_(false),
31    cpu_vendor_("unknown") {
32  Initialize();
33}
34
35#if defined(ARCH_CPU_X86_FAMILY)
36#ifndef _MSC_VER
37
38#if defined(__pic__) && defined(__i386__)
39
40void __cpuid(int cpu_info[4], int info_type) {
41  __asm__ volatile (
42    "mov %%ebx, %%edi\n"
43    "cpuid\n"
44    "xchg %%edi, %%ebx\n"
45    : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
46    : "a"(info_type)
47  );
48}
49
50void __cpuidex(int cpu_info[4], int info_type, int info_index) {
51  __asm__ volatile (
52    "mov %%ebx, %%edi\n"
53    "cpuid\n"
54    "xchg %%edi, %%ebx\n"
55    : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
56    : "a"(info_type), "c"(info_index)
57  );
58}
59
60#else
61
62void __cpuid(int cpu_info[4], int info_type) {
63  __asm__ volatile (
64    "cpuid \n\t"
65    : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
66    : "a"(info_type)
67  );
68}
69
70void __cpuidex(int cpu_info[4], int info_type, int info_index) {
71  __asm__ volatile (
72    "cpuid \n\t"
73    : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
74    : "a"(info_type), "c"(info_index)
75  );
76}
77
78#endif
79#endif  // _MSC_VER
80#endif  // ARCH_CPU_X86_FAMILY
81
82void CPU::Initialize() {
83#if defined(ARCH_CPU_X86_FAMILY)
84  int cpu_info[4] = {-1};
85  char cpu_string[0x20];
86
87  // __cpuid with an InfoType argument of 0 returns the number of
88  // valid Ids in CPUInfo[0] and the CPU identification string in
89  // the other three array elements. The CPU identification string is
90  // not in linear order. The code below arranges the information
91  // in a human readable form.
92  //
93  // More info can be found here:
94  // http://msdn.microsoft.com/en-us/library/hskdteyh.aspx
95  __cpuid(cpu_info, 0);
96  int num_ids = cpu_info[0];
97  memset(cpu_string, 0, sizeof(cpu_string));
98  *(reinterpret_cast<int*>(cpu_string)) = cpu_info[1];
99  *(reinterpret_cast<int*>(cpu_string+4)) = cpu_info[3];
100  *(reinterpret_cast<int*>(cpu_string+8)) = cpu_info[2];
101
102  // Interpret CPU feature information.
103  if (num_ids > 0) {
104    __cpuid(cpu_info, 1);
105    stepping_ = cpu_info[0] & 0xf;
106    model_ = ((cpu_info[0] >> 4) & 0xf) + ((cpu_info[0] >> 12) & 0xf0);
107    family_ = (cpu_info[0] >> 8) & 0xf;
108    type_ = (cpu_info[0] >> 12) & 0x3;
109    ext_model_ = (cpu_info[0] >> 16) & 0xf;
110    ext_family_ = (cpu_info[0] >> 20) & 0xff;
111    cpu_vendor_ = cpu_string;
112    has_mmx_ = (cpu_info[3] & 0x00800000) != 0;
113    has_sse_ = (cpu_info[3] & 0x02000000) != 0;
114    has_sse2_ = (cpu_info[3] & 0x04000000) != 0;
115    has_sse3_ = (cpu_info[2] & 0x00000001) != 0;
116    has_ssse3_ = (cpu_info[2] & 0x00000200) != 0;
117    has_sse41_ = (cpu_info[2] & 0x00080000) != 0;
118    has_sse42_ = (cpu_info[2] & 0x00100000) != 0;
119  }
120#endif
121}
122
123}  // namespace base
124