System: Check host page size on startup

src/util/platform_misc_win32.cpp

@@ -8,7 +8,9 @@
 #include "common/small_string.h"
 #include "common/string_util.h"
 
+#include <algorithm>
 #include <cinttypes>
+#include <memory>
 
 #include "common/windows_headers.h"
 #include <mmsystem.h>
@@ -53,6 +55,35 @@ void PlatformMisc::ResumeScreensaver()
   s_screensaver_suspended = false;
 }
 
+size_t PlatformMisc::GetRuntimePageSize()
+{
+  SYSTEM_INFO si = {};
+  GetSystemInfo(&si);
+  return si.dwPageSize;
+}
+
+size_t PlatformMisc::GetRuntimeCacheLineSize()
+{
+  DWORD size = 0;
+  if (!GetLogicalProcessorInformation(nullptr, &size) && GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+    return 0;
+
+  std::unique_ptr<SYSTEM_LOGICAL_PROCESSOR_INFORMATION[]> lpi =
+    std::make_unique<SYSTEM_LOGICAL_PROCESSOR_INFORMATION[]>(
+      (size + (sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION) - 1)) / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION));
+  if (!GetLogicalProcessorInformation(lpi.get(), &size))
+    return 0;
+
+  u32 max_line_size = 0;
+  for (u32 i = 0; i < size / sizeof(SYSTEM_LOGICAL_PROCESSOR_INFORMATION); i++)
+  {
+    if (lpi[i].Relationship == RelationCache)
+      max_line_size = std::max<u32>(max_line_size, lpi[i].Cache.LineSize);
+  }
+
+  return max_line_size;
+}
+
 bool PlatformMisc::PlaySoundAsync(const char* path)
 {
   const std::wstring wpath(FileSystem::GetWin32Path(path));