Implement get_num_physical_cores() for Windows

Author: DannyDaemonic

examples/common.cpp

@@ -15,18 +15,11 @@
 #endif
 
 #if defined (_WIN32)
+#define WIN32_LEAN_AND_MEAN
+#define NOMINMAX
+#include <windows.h>
 #include <fcntl.h>
 #include <io.h>
-#pragma comment(lib,"kernel32.lib")
-extern "C" __declspec(dllimport) void* __stdcall GetStdHandle(unsigned long nStdHandle);
-extern "C" __declspec(dllimport) int __stdcall GetConsoleMode(void* hConsoleHandle, unsigned long* lpMode);
-extern "C" __declspec(dllimport) int __stdcall SetConsoleMode(void* hConsoleHandle, unsigned long dwMode);
-extern "C" __declspec(dllimport) int __stdcall SetConsoleCP(unsigned int wCodePageID);
-extern "C" __declspec(dllimport) int __stdcall SetConsoleOutputCP(unsigned int wCodePageID);
-extern "C" __declspec(dllimport) int __stdcall WideCharToMultiByte(unsigned int CodePage, unsigned long dwFlags,
-                                                                   const wchar_t * lpWideCharStr, int cchWideChar,
-                                                                   char * lpMultiByteStr, int cbMultiByte,
-                                                                   const char * lpDefaultChar, bool * lpUsedDefaultChar);
 #define CP_UTF8 65001
 #endif
 
@@ -60,7 +53,71 @@ int32_t get_num_physical_cores() {
         return num_physical_cores;
     }
 #elif defined(_WIN32)
-    //TODO: Implement
+    SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX *buffer = nullptr;
+    DWORD length = 0;
+
+    // Call GetLogicalProcessorInformationEx with a nullptr buffer to get the required buffer length
+    GetLogicalProcessorInformationEx(RelationAll, nullptr, &length);
+
+    // Allocate memory for the buffer
+    buffer = static_cast<SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX *>(malloc(length));
+
+    // Things to count
+    unsigned int physical_cores = 0;
+    unsigned int physical_performance_cores = 0;
+    unsigned int physical_efficiency_cores = 0;
+    unsigned int logical_cores = 0;
+    unsigned int logical_performance_cores = 0;
+    unsigned int logical_efficiency_cores = 0;
+
+    // Call GetLogicalProcessorInformationEx again with the allocated buffer
+    if (GetLogicalProcessorInformationEx(RelationAll, buffer, &length)) {
+        DWORD offset = 0;
+
+        while (offset < length) {
+            auto info = reinterpret_cast<SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX *>(reinterpret_cast<char *>(buffer) + offset);
+
+            if (info->Relationship == RelationProcessorCore) {
+                physical_cores += info->Processor.GroupCount;
+
+                for (WORD i = 0; i < info->Processor.GroupCount; ++i) {
+                    int core_count = static_cast<int>(__popcnt64(info->Processor.GroupMask[i].Mask));
+                    logical_cores += core_count;
+
+                    // Assuming EfficiencyClass 0 represents performance cores, and others represent efficiency cores
+                    if (info->Processor.EfficiencyClass == 0) {
+                        physical_performance_cores++;
+                        logical_performance_cores += core_count;
+                    } else {
+                        physical_efficiency_cores++;
+                        logical_efficiency_cores += core_count;
+                    }
+                }
+            }
+            offset += info->Size;
+        }
+
+        // TODO: Remove this once we've verified it's working
+        fprintf(stderr,
+                "Physical Cores: %u\n"
+                "  - Performance Cores: %u\n"
+                "  - Efficiency Cores: %u\n"
+                "Logical Cores: %u\n"
+                "  - Performance Cores: %u\n"
+                "  - Efficiency Cores: %u\n",
+                physical_cores, physical_performance_cores, physical_efficiency_cores,
+                logical_cores, logical_performance_cores, logical_efficiency_cores);
+    } else {
+        printf("Failed to get processor information. Error: %u\n", GetLastError());
+    }
+
+    free(buffer);
+
+    if (physical_performance_cores > 0) {
+        return static_cast<int32_t>(physical_performance_cores);
+    } else if (physical_cores > 0) {
+        return static_cast<int32_t>(physical_cores);
+    }
 #endif
     unsigned int n_threads = std::thread::hardware_concurrency();
     return n_threads > 0 ? (n_threads <= 4 ? n_threads : n_threads / 2) : 4;
@@ -69,7 +126,6 @@ int32_t get_num_physical_cores() {
 bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
     bool invalid_param = false;
     std::string arg;
-    gpt_params default_params;
 
     for (int i = 1; i < argc; i++) {
         arg = argv[i];
@@ -287,7 +343,7 @@ bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
             }
             params.n_parts = std::stoi(argv[i]);
         } else if (arg == "-h" || arg == "--help") {
-            gpt_print_usage(argc, argv, default_params);
+            gpt_print_usage(argc, argv);
             exit(0);
         } else if (arg == "--random-prompt") {
             params.random_prompt = true;
@@ -299,20 +355,22 @@ bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
             params.input_prefix = argv[i];
         } else {
             fprintf(stderr, "error: unknown argument: %s\n", arg.c_str());
-            gpt_print_usage(argc, argv, default_params);
+            gpt_print_usage(argc, argv);
             exit(1);
         }
     }
     if (invalid_param) {
         fprintf(stderr, "error: invalid parameter for argument: %s\n", arg.c_str());
-        gpt_print_usage(argc, argv, default_params);
+        gpt_print_usage(argc, argv);
         exit(1);
     }
 
     return true;
 }
 
-void gpt_print_usage(int /*argc*/, char ** argv, const gpt_params & params) {
+void gpt_print_usage(int /*argc*/, char ** argv) {
+    gpt_params params;
+
     fprintf(stderr, "usage: %s [options]\n", argv[0]);
     fprintf(stderr, "\n");
     fprintf(stderr, "options:\n");

examples/common.h

@@ -67,7 +67,7 @@ struct gpt_params {
 
 bool gpt_params_parse(int argc, char ** argv, gpt_params & params);
 
-void gpt_print_usage(int argc, char ** argv, const gpt_params & params);
+void gpt_print_usage(int argc, char ** argv);
 
 std::string gpt_random_prompt(std::mt19937 & rng);