Merge pull request #7936 from Wunkolo/cpu_detect

cpu_detect: Refactor detection of processor features

src/common/bit_util.h

@@ -57,4 +57,11 @@ requires std::is_integral_v<T>
     return static_cast<T>(1ULL << ((8U * sizeof(T)) - std::countl_zero(value - 1U)));
 }
 
+template <size_t bit_index, typename T>
+requires std::is_integral_v<T>
+[[nodiscard]] constexpr bool Bit(const T value) {
+    static_assert(bit_index < BitSize<T>(), "bit_index must be smaller than size of T");
+    return ((value >> bit_index) & T(1)) == T(1);
+}
+
 } // namespace Common

src/common/x64/cpu_detect.cpp

@@ -1,8 +1,12 @@
-// Copyright 2013 Dolphin Emulator Project / 2015 Citra Emulator Project
+// Copyright 2013 Dolphin Emulator Project / 2015 Citra Emulator Project / 2022 Yuzu Emulator
-// Licensed under GPLv2 or any later version
+// Project Licensed under GPLv2 or any later version Refer to the license.txt file included.
-// Refer to the license.txt file included.
 
+#include <array>
 #include <cstring>
+#include <iterator>
+#include <span>
+#include <string_view>
+#include "common/bit_util.h"
 #include "common/common_types.h"
 #include "common/x64/cpu_detect.h"
 
@@ -17,7 +21,7 @@
 // clang-format on
 #endif
 
-static inline void __cpuidex(int info[4], int function_id, int subfunction_id) {
+static inline void __cpuidex(const std::span<u32, 4> info, u32 function_id, u32 subfunction_id) {
 #if defined(__DragonFly__) || defined(__FreeBSD__)
     // Despite the name, this is just do_cpuid() with ECX as second input.
     cpuid_count((u_int)function_id, (u_int)subfunction_id, (u_int*)info);
@@ -30,7 +34,7 @@ static inline void __cpuidex(int info[4], int function_id, int subfunction_id) {
 #endif
 }
 
-static inline void __cpuid(int info[4], int function_id) {
+static inline void __cpuid(const std::span<u32, 4> info, u32 function_id) {
     return __cpuidex(info, function_id, 0);
 }
 
@@ -45,6 +49,17 @@ static inline u64 _xgetbv(u32 index) {
 
 namespace Common {
 
+CPUCaps::Manufacturer CPUCaps::ParseManufacturer(std::string_view brand_string) {
+    if (brand_string == "GenuineIntel") {
+        return Manufacturer::Intel;
+    } else if (brand_string == "AuthenticAMD") {
+        return Manufacturer::AMD;
+    } else if (brand_string == "HygonGenuine") {
+        return Manufacturer::Hygon;
+    }
+    return Manufacturer::Unknown;
+}
+
 // Detects the various CPU features
 static CPUCaps Detect() {
     CPUCaps caps = {};
@@ -52,58 +67,45 @@ static CPUCaps Detect() {
     // Assumes the CPU supports the CPUID instruction. Those that don't would likely not support
     // yuzu at all anyway
 
-    int cpu_id[4];
+    std::array<u32, 4> cpu_id;
-    memset(caps.brand_string, 0, sizeof(caps.brand_string));
 
-    // Detect CPU's CPUID capabilities and grab CPU string
+    // Detect CPU's CPUID capabilities and grab manufacturer string
     __cpuid(cpu_id, 0x00000000);
-    u32 max_std_fn = cpu_id[0]; // EAX
+    const u32 max_std_fn = cpu_id[0]; // EAX
 
-    std::memcpy(&caps.brand_string[0], &cpu_id[1], sizeof(int));
+    std::memset(caps.brand_string, 0, std::size(caps.brand_string));
-    std::memcpy(&caps.brand_string[4], &cpu_id[3], sizeof(int));
+    std::memcpy(&caps.brand_string[0], &cpu_id[1], sizeof(u32));
-    std::memcpy(&caps.brand_string[8], &cpu_id[2], sizeof(int));
+    std::memcpy(&caps.brand_string[4], &cpu_id[3], sizeof(u32));
-    if (cpu_id[1] == 0x756e6547 && cpu_id[2] == 0x6c65746e && cpu_id[3] == 0x49656e69)
+    std::memcpy(&caps.brand_string[8], &cpu_id[2], sizeof(u32));
-        caps.manufacturer = Manufacturer::Intel;
+
-    else if (cpu_id[1] == 0x68747541 && cpu_id[2] == 0x444d4163 && cpu_id[3] == 0x69746e65)
+    caps.manufacturer = CPUCaps::ParseManufacturer(caps.brand_string);
-        caps.manufacturer = Manufacturer::AMD;
+
-    else if (cpu_id[1] == 0x6f677948 && cpu_id[2] == 0x656e6975 && cpu_id[3] == 0x6e65476e)
+    // Set reasonable default cpu string even if brand string not available
-        caps.manufacturer = Manufacturer::Hygon;
+    std::strncpy(caps.cpu_string, caps.brand_string, std::size(caps.brand_string));
-    else
-        caps.manufacturer = Manufacturer::Unknown;
 
     __cpuid(cpu_id, 0x80000000);
 
-    u32 max_ex_fn = cpu_id[0];
+    const u32 max_ex_fn = cpu_id[0];
-
-    // Set reasonable default brand string even if brand string not available
-    strcpy(caps.cpu_string, caps.brand_string);
 
     // Detect family and other miscellaneous features
     if (max_std_fn >= 1) {
         __cpuid(cpu_id, 0x00000001);
-        if ((cpu_id[3] >> 25) & 1)
+        caps.sse = Common::Bit<25>(cpu_id[3]);
-            caps.sse = true;
+        caps.sse2 = Common::Bit<26>(cpu_id[3]);
-        if ((cpu_id[3] >> 26) & 1)
+        caps.sse3 = Common::Bit<0>(cpu_id[2]);
-            caps.sse2 = true;
+        caps.ssse3 = Common::Bit<9>(cpu_id[2]);
-        if ((cpu_id[2]) & 1)
+        caps.sse4_1 = Common::Bit<19>(cpu_id[2]);
-            caps.sse3 = true;
+        caps.sse4_2 = Common::Bit<20>(cpu_id[2]);
-        if ((cpu_id[2] >> 9) & 1)
+        caps.aes = Common::Bit<25>(cpu_id[2]);
-            caps.ssse3 = true;
-        if ((cpu_id[2] >> 19) & 1)
-            caps.sse4_1 = true;
-        if ((cpu_id[2] >> 20) & 1)
-            caps.sse4_2 = true;
-        if ((cpu_id[2] >> 25) & 1)
-            caps.aes = true;
 
         // AVX support requires 3 separate checks:
         //  - Is the AVX bit set in CPUID?
         //  - Is the XSAVE bit set in CPUID?
         //  - XGETBV result has the XCR bit set.
-        if (((cpu_id[2] >> 28) & 1) && ((cpu_id[2] >> 27) & 1)) {
+        if (Common::Bit<28>(cpu_id[2]) && Common::Bit<27>(cpu_id[2])) {
             if ((_xgetbv(_XCR_XFEATURE_ENABLED_MASK) & 0x6) == 0x6) {
                 caps.avx = true;
-                if ((cpu_id[2] >> 12) & 1)
+                if (Common::Bit<12>(cpu_id[2]))
                     caps.fma = true;
             }
         }
@@ -111,15 +113,13 @@ static CPUCaps Detect() {
         if (max_std_fn >= 7) {
             __cpuidex(cpu_id, 0x00000007, 0x00000000);
             // Can't enable AVX2 unless the XSAVE/XGETBV checks above passed
-            if ((cpu_id[1] >> 5) & 1)
+            caps.avx2 = caps.avx && Common::Bit<5>(cpu_id[1]);
-                caps.avx2 = caps.avx;
+            caps.bmi1 = Common::Bit<3>(cpu_id[1]);
-            if ((cpu_id[1] >> 3) & 1)
+            caps.bmi2 = Common::Bit<8>(cpu_id[1]);
-                caps.bmi1 = true;
-            if ((cpu_id[1] >> 8) & 1)
-                caps.bmi2 = true;
             // Checks for AVX512F, AVX512CD, AVX512VL, AVX512DQ, AVX512BW (Intel Skylake-X/SP)
-            if ((cpu_id[1] >> 16) & 1 && (cpu_id[1] >> 28) & 1 && (cpu_id[1] >> 31) & 1 &&
+            if (Common::Bit<16>(cpu_id[1]) && Common::Bit<28>(cpu_id[1]) &&
-                (cpu_id[1] >> 17) & 1 && (cpu_id[1] >> 30) & 1) {
+                Common::Bit<31>(cpu_id[1]) && Common::Bit<17>(cpu_id[1]) &&
+                Common::Bit<30>(cpu_id[1])) {
                 caps.avx512 = caps.avx2;
             }
         }
@@ -128,25 +128,23 @@ static CPUCaps Detect() {
     if (max_ex_fn >= 0x80000004) {
         // Extract CPU model string
         __cpuid(cpu_id, 0x80000002);
-        std::memcpy(caps.cpu_string, cpu_id, sizeof(cpu_id));
+        std::memcpy(caps.cpu_string, cpu_id.data(), sizeof(cpu_id));
         __cpuid(cpu_id, 0x80000003);
-        std::memcpy(caps.cpu_string + 16, cpu_id, sizeof(cpu_id));
+        std::memcpy(caps.cpu_string + 16, cpu_id.data(), sizeof(cpu_id));
         __cpuid(cpu_id, 0x80000004);
-        std::memcpy(caps.cpu_string + 32, cpu_id, sizeof(cpu_id));
+        std::memcpy(caps.cpu_string + 32, cpu_id.data(), sizeof(cpu_id));
     }
 
     if (max_ex_fn >= 0x80000001) {
         // Check for more features
         __cpuid(cpu_id, 0x80000001);
-        if ((cpu_id[2] >> 16) & 1)
+        caps.lzcnt = Common::Bit<5>(cpu_id[2]);
-            caps.fma4 = true;
+        caps.fma4 = Common::Bit<16>(cpu_id[2]);
     }
 
     if (max_ex_fn >= 0x80000007) {
         __cpuid(cpu_id, 0x80000007);
-        if (cpu_id[3] & (1 << 8)) {
+        caps.invariant_tsc = Common::Bit<8>(cpu_id[3]);
-            caps.invariant_tsc = true;
-        }
     }
 
     if (max_std_fn >= 0x16) {

src/common/x64/cpu_detect.h

@@ -1,42 +1,50 @@
-// Copyright 2013 Dolphin Emulator Project / 2015 Citra Emulator Project
+// Copyright 2013 Dolphin Emulator Project / 2015 Citra Emulator Project / 2022 Yuzu Emulator
-// Licensed under GPLv2 or any later version
+// Project Project Licensed under GPLv2 or any later version Refer to the license.txt file included.
-// Refer to the license.txt file included.
 
 #pragma once
 
-namespace Common {
+#include <string_view>
+#include "common/common_types.h"
 
-enum class Manufacturer : u32 {
+namespace Common {
-    Intel = 0,
-    AMD = 1,
-    Hygon = 2,
-    Unknown = 3,
-};
 
 /// x86/x64 CPU capabilities that may be detected by this module
 struct CPUCaps {
+
+    enum class Manufacturer : u8 {
+        Unknown = 0,
+        Intel = 1,
+        AMD = 2,
+        Hygon = 3,
+    };
+
+    static Manufacturer ParseManufacturer(std::string_view brand_string);
+
     Manufacturer manufacturer;
-    char cpu_string[0x21];
+    char brand_string[13];
-    char brand_string[0x41];
+
-    bool sse;
+    char cpu_string[48];
-    bool sse2;
+
-    bool sse3;
-    bool ssse3;
-    bool sse4_1;
-    bool sse4_2;
-    bool lzcnt;
-    bool avx;
-    bool avx2;
-    bool avx512;
-    bool bmi1;
-    bool bmi2;
-    bool fma;
-    bool fma4;
-    bool aes;
-    bool invariant_tsc;
     u32 base_frequency;
     u32 max_frequency;
     u32 bus_frequency;
+
+    bool sse : 1;
+    bool sse2 : 1;
+    bool sse3 : 1;
+    bool ssse3 : 1;
+    bool sse4_1 : 1;
+    bool sse4_2 : 1;
+    bool lzcnt : 1;
+    bool avx : 1;
+    bool avx2 : 1;
+    bool avx512 : 1;
+    bool bmi1 : 1;
+    bool bmi2 : 1;
+    bool fma : 1;
+    bool fma4 : 1;
+    bool aes : 1;
+    bool invariant_tsc : 1;
 };
 
 /**