1// Copyright 2011 Google Inc. All Rights Reserved.
2//
3// Use of this source code is governed by a BSD-style license
4// that can be found in the COPYING file in the root of the source
5// tree. An additional intellectual property rights grant can be found
6// in the file PATENTS. All contributing project authors may
7// be found in the AUTHORS file in the root of the source tree.
8// -----------------------------------------------------------------------------
9//
10// CPU detection
11//
12// Author: Christian Duvivier (cduvivier@google.com)
13
14#include "./dsp.h"
15
16#if defined(WEBP_HAVE_NEON_RTCD)
17#include <stdio.h>
18#include <string.h>
19#endif
20
21#if defined(WEBP_ANDROID_NEON)
22#include <cpu-features.h>
23#endif
24
25//------------------------------------------------------------------------------
26// SSE2 detection.
27//
28
29// apple/darwin gcc-4.0.1 defines __PIC__, but not __pic__ with -fPIC.
30#if (defined(__pic__) || defined(__PIC__)) && defined(__i386__)
31static WEBP_INLINE void GetCPUInfo(int cpu_info[4], int info_type) {
32 __asm__ volatile (
33 "mov %%ebx, %%edi\n"
34 "cpuid\n"
35 "xchg %%edi, %%ebx\n"
36 : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
37 : "a"(info_type), "c"(0));
38}
39#elif defined(__x86_64__) && \
40 (defined(__code_model_medium__) || defined(__code_model_large__)) && \
41 defined(__PIC__)
42static WEBP_INLINE void GetCPUInfo(int cpu_info[4], int info_type) {
43 __asm__ volatile (
44 "xchg{q}\t{%%rbx}, %q1\n"
45 "cpuid\n"
46 "xchg{q}\t{%%rbx}, %q1\n"
47 : "=a"(cpu_info[0]), "=&r"(cpu_info[1]), "=c"(cpu_info[2]),
48 "=d"(cpu_info[3])
49 : "a"(info_type), "c"(0));
50}
51#elif defined(__i386__) || defined(__x86_64__)
52static WEBP_INLINE void GetCPUInfo(int cpu_info[4], int info_type) {
53 __asm__ volatile (
54 "cpuid\n"
55 : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]), "=d"(cpu_info[3])
56 : "a"(info_type), "c"(0));
57}
58#elif (defined(_M_X64) || defined(_M_IX86)) && \
59 defined(_MSC_FULL_VER) && _MSC_FULL_VER >= 150030729 // >= VS2008 SP1
60#include <intrin.h>
61#define GetCPUInfo(info, type) __cpuidex(info, type, 0) // set ecx=0
62#elif defined(WEBP_MSC_SSE2)
63#define GetCPUInfo __cpuid
64#endif
65
66// NaCl has no support for xgetbv or the raw opcode.
67#if !defined(__native_client__) && (defined(__i386__) || defined(__x86_64__))
68static WEBP_INLINE uint64_t xgetbv(void) {
69 const uint32_t ecx = 0;
70 uint32_t eax, edx;
71 // Use the raw opcode for xgetbv for compatibility with older toolchains.
72 __asm__ volatile (
73 ".byte 0x0f, 0x01, 0xd0\n"
74 : "=a"(eax), "=d"(edx) : "c" (ecx));
75 return ((uint64_t)edx << 32) | eax;
76}
77#elif (defined(_M_X64) || defined(_M_IX86)) && \
78 defined(_MSC_FULL_VER) && _MSC_FULL_VER >= 160040219 // >= VS2010 SP1
79#include <immintrin.h>
80#define xgetbv() _xgetbv(0)
81#elif defined(_MSC_VER) && defined(_M_IX86)
82static WEBP_INLINE uint64_t xgetbv(void) {
83 uint32_t eax_, edx_;
84 __asm {
85 xor ecx, ecx // ecx = 0
86 // Use the raw opcode for xgetbv for compatibility with older toolchains.
87 __asm _emit 0x0f __asm _emit 0x01 __asm _emit 0xd0
88 mov eax_, eax
89 mov edx_, edx
90 }
91 return ((uint64_t)edx_ << 32) | eax_;
92}
93#else
94#define xgetbv() 0U // no AVX for older x64 or unrecognized toolchains.
95#endif
96
97#if defined(__i386__) || defined(__x86_64__) || defined(WEBP_MSC_SSE2)
98
99// helper function for run-time detection of slow SSSE3 platforms
100static int CheckSlowModel(int info) {
101 // Table listing display models with longer latencies for the bsr instruction
102 // (ie 2 cycles vs 10/16 cycles) and some SSSE3 instructions like pshufb.
103 // Refer to Intel 64 and IA-32 Architectures Optimization Reference Manual.
104 static const uint8_t kSlowModels[] = {
105 0x37, 0x4a, 0x4d, // Silvermont Microarchitecture
106 0x1c, 0x26, 0x27 // Atom Microarchitecture
107 };
108 const uint32_t model = ((info & 0xf0000) >> 12) | ((info >> 4) & 0xf);
109 const uint32_t family = (info >> 8) & 0xf;
110 if (family == 0x06) {
111 size_t i;
112 for (i = 0; i < sizeof(kSlowModels) / sizeof(kSlowModels[0]); ++i) {
113 if (model == kSlowModels[i]) return 1;
114 }
115 }
116 return 0;
117}
118
119static int x86CPUInfo(CPUFeature feature) {
120 int max_cpuid_value;
121 int cpu_info[4];
122 int is_intel = 0;
123
124 // get the highest feature value cpuid supports
125 GetCPUInfo(cpu_info, 0);
126 max_cpuid_value = cpu_info[0];
127 if (max_cpuid_value < 1) {
128 return 0;
129 } else {
130 const int VENDOR_ID_INTEL_EBX = 0x756e6547; // uneG
131 const int VENDOR_ID_INTEL_EDX = 0x49656e69; // Ieni
132 const int VENDOR_ID_INTEL_ECX = 0x6c65746e; // letn
133 is_intel = (cpu_info[1] == VENDOR_ID_INTEL_EBX &&
134 cpu_info[2] == VENDOR_ID_INTEL_ECX &&
135 cpu_info[3] == VENDOR_ID_INTEL_EDX); // genuine Intel?
136 }
137
138 GetCPUInfo(cpu_info, 1);
139 if (feature == kSSE2) {
140 return !!(cpu_info[3] & (1 << 26));
141 }
142 if (feature == kSSE3) {
143 return !!(cpu_info[2] & (1 << 0));
144 }
145 if (feature == kSlowSSSE3) {
146 if (is_intel && (cpu_info[2] & (1 << 0))) { // SSSE3?
147 return CheckSlowModel(cpu_info[0]);
148 }
149 return 0;
150 }
151
152 if (feature == kSSE4_1) {
153 return !!(cpu_info[2] & (1 << 19));
154 }
155 if (feature == kAVX) {
156 // bits 27 (OSXSAVE) & 28 (256-bit AVX)
157 if ((cpu_info[2] & 0x18000000) == 0x18000000) {
158 // XMM state and YMM state enabled by the OS.
159 return (xgetbv() & 0x6) == 0x6;
160 }
161 }
162 if (feature == kAVX2) {
163 if (x86CPUInfo(kAVX) && max_cpuid_value >= 7) {
164 GetCPUInfo(cpu_info, 7);
165 return !!(cpu_info[1] & (1 << 5));
166 }
167 }
168 return 0;
169}
170VP8CPUInfo VP8GetCPUInfo = x86CPUInfo;
171#elif defined(WEBP_ANDROID_NEON) // NB: needs to be before generic NEON test.
172static int AndroidCPUInfo(CPUFeature feature) {
173 const AndroidCpuFamily cpu_family = android_getCpuFamily();
174 const uint64_t cpu_features = android_getCpuFeatures();
175 if (feature == kNEON) {
176 return (cpu_family == ANDROID_CPU_FAMILY_ARM &&
177 0 != (cpu_features & ANDROID_CPU_ARM_FEATURE_NEON));
178 }
179 return 0;
180}
181VP8CPUInfo VP8GetCPUInfo = AndroidCPUInfo;
182#elif defined(WEBP_USE_NEON)
183// define a dummy function to enable turning off NEON at runtime by setting
184// VP8DecGetCPUInfo = NULL
185static int armCPUInfo(CPUFeature feature) {
186 if (feature != kNEON) return 0;
187#if defined(__linux__) && defined(WEBP_HAVE_NEON_RTCD)
188 {
189 int has_neon = 0;
190 char line[200];
191 FILE* const cpuinfo = fopen("/proc/cpuinfo", "r");
192 if (cpuinfo == NULL) return 0;
193 while (fgets(line, sizeof(line), cpuinfo)) {
194 if (!strncmp(line, "Features", 8)) {
195 if (strstr(line, " neon ") != NULL) {
196 has_neon = 1;
197 break;
198 }
199 }
200 }
201 fclose(cpuinfo);
202 return has_neon;
203 }
204#else
205 return 1;
206#endif
207}
208VP8CPUInfo VP8GetCPUInfo = armCPUInfo;
209#elif defined(WEBP_USE_MIPS32) || defined(WEBP_USE_MIPS_DSP_R2) || \
210 defined(WEBP_USE_MSA)
211static int mipsCPUInfo(CPUFeature feature) {
212 if ((feature == kMIPS32) || (feature == kMIPSdspR2) || (feature == kMSA)) {
213 return 1;
214 } else {
215 return 0;
216 }
217
218}
219VP8CPUInfo VP8GetCPUInfo = mipsCPUInfo;
220#else
221VP8CPUInfo VP8GetCPUInfo = NULL;
222#endif
223