1 /*
2 * Copyright (C) 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "berberis/runtime_primitives/platform.h"
18 #include "berberis/base/config_globals.h"
19
20 #if defined(__i386__) || defined(__x86_64__)
21 #include <cpuid.h>
22 #endif
23
24 #include <cinttypes>
25
26 namespace berberis::host_platform {
27
28 namespace {
29
30 #if defined(__i386__) || defined(__x86_64__)
Init()31 auto Init() {
32 PlatformCapabilities platform_capabilities = {};
33 unsigned int eax, ebx, ecx, edx;
34 // Technically Zen,Zen+/Zen2 AMD CPUs support BMI2 and thus PDEP/PEXT instruction, but they are
35 // not usable there: https://twitter.com/instlatx64/status/1322503571288559617
36 // That's why we need special emulated CPUID flag for these instructions.
37 bool use_pdep_if_present = true;
38 __cpuid(0, eax, ebx, ecx, edx);
39 if (((ebx == signature_AMD_ebx && ecx == signature_AMD_ecx && edx == signature_AMD_edx) ||
40 (ebx == signature_HYGON_ebx && ecx == signature_HYGON_ecx && edx == signature_HYGON_edx))) {
41 platform_capabilities.kIsAuthenticAMD = true;
42 __cpuid(1, eax, ebx, ecx, edx);
43 uint8_t family = (eax >> 8) & 0b1111;
44 if (family == 0b1111) {
45 family += (eax >> 20) & 0b11111111;
46 if (family < 0x19) {
47 use_pdep_if_present = false;
48 }
49 }
50 } else {
51 __cpuid(1, eax, ebx, ecx, edx);
52 }
53 platform_capabilities.kHasAES = ecx & bit_AES;
54 platform_capabilities.kHasAVX = ecx & bit_AVX;
55 platform_capabilities.kHasCLMUL = ecx & bit_PCLMUL;
56 platform_capabilities.kHasF16C = ecx & bit_F16C;
57 platform_capabilities.kHasFMA = ecx & bit_FMA;
58 platform_capabilities.kHasPOPCNT = ecx & bit_POPCNT;
59 platform_capabilities.kHasSSE3 = ecx & bit_SSE3;
60 platform_capabilities.kHasSSSE3 = ecx & bit_SSSE3;
61 platform_capabilities.kHasSSE4_1 = ecx & bit_SSE4_1;
62 platform_capabilities.kHasSSE4_2 = ecx & bit_SSE4_2;
63 __cpuid(0x80000001, eax, ebx, ecx, edx);
64 platform_capabilities.kHasFMA4 = ecx & bit_FMA4;
65 platform_capabilities.kHasLZCNT = ecx & bit_LZCNT;
66 platform_capabilities.kHasSSE4a = ecx & bit_SSE4a;
67 __cpuid_count(7, 0, eax, ebx, ecx, edx);
68 platform_capabilities.kHasBMI = ebx & bit_BMI;
69 platform_capabilities.kHasBMI2 = ebx & bit_BMI2;
70 platform_capabilities.kHasPDEP = ebx & bit_BMI2 && use_pdep_if_present;
71 platform_capabilities.kHasSHA = ebx & bit_SHA;
72 platform_capabilities.kHasCustomCapability = IsConfigFlagSet(kPlatformCustomCPUCapability);
73 return platform_capabilities;
74 }
75 #endif
76
77 } // namespace
78
79 #if defined(__i386__) || defined(__x86_64__)
80 const PlatformCapabilities kPlatformCapabilities = Init();
81 #endif
82
83 } // namespace berberis::host_platform
84