Initial commit of snmalloc

History squashed from internal development.

Internal history has commit hash:
  e27a0e485c44a5003a802de2661ce3b21e120316

src/test/usage.h

@@ -0,0 +1,42 @@
+#pragma once
+
+#if defined(_WIN32)
+#  define WIN32_LEAN_AND_MEAN
+#  define NOMINMAX
+#  include <windows.h>
+// Needs to be included after windows.h
+#  include <psapi.h>
+#endif
+
+#include <iomanip>
+#include <iostream>
+
+namespace usage
+{
+  void print_memory()
+  {
+#if defined(_WIN32)
+    PROCESS_MEMORY_COUNTERS_EX pmc;
+
+    if (!GetProcessMemoryInfo(
+          GetCurrentProcess(), (PROCESS_MEMORY_COUNTERS*)&pmc, sizeof(pmc)))
+      return;
+
+    std::cout << "Memory info:" << std::endl
+              << "\tPageFaultCount: " << pmc.PageFaultCount << std::endl
+              << "\tPeakWorkingSetSize: " << pmc.PeakWorkingSetSize << std::endl
+              << "\tWorkingSetSize: " << pmc.WorkingSetSize << std::endl
+              << "\tQuotaPeakPagedPoolUsage: " << pmc.QuotaPeakPagedPoolUsage
+              << std::endl
+              << "\tQuotaPagedPoolUsage: " << pmc.QuotaPagedPoolUsage
+              << std::endl
+              << "\tQuotaPeakNonPagedPoolUsage: "
+              << pmc.QuotaPeakNonPagedPoolUsage << std::endl
+              << "\tQuotaNonPagedPoolUsage: " << pmc.QuotaNonPagedPoolUsage
+              << std::endl
+              << "\tPagefileUsage: " << pmc.PagefileUsage << std::endl
+              << "\tPeakPagefileUsage: " << pmc.PeakPagefileUsage << std::endl
+              << "\tPrivateUsage: " << pmc.PrivateUsage << std::endl;
+#endif
+  }
+};