+inline uint64_t mul_hi64(uint64_t a, uint64_t b) {
+#if defined(__GNUC__) && defined(IS_64BIT)
+ __extension__ using uint128 = unsigned __int128;
+ return (uint128(a) * uint128(b)) >> 64;
+#else
+ uint64_t aL = uint32_t(a), aH = a >> 32;
+ uint64_t bL = uint32_t(b), bH = b >> 32;
+ uint64_t c1 = (aL * bL) >> 32;
+ uint64_t c2 = aH * bL + c1;
+ uint64_t c3 = aL * bH + uint32_t(c2);
+ return aH * bH + (c2 >> 32) + (c3 >> 32);
+#endif
+}
+
+// Under Windows it is not possible for a process to run on more than one
+// logical processor group. This usually means being limited to using max 64
+// cores. To overcome this, some special platform-specific API should be
+// called to set group affinity for each thread. Original code from Texel by
+// Peter Ă–sterlund.
+namespace WinProcGroup {
+void bindThisThread(size_t idx);
+}
+
+namespace CommandLine {
+void init(int argc, char* argv[]);
+
+extern std::string binaryDirectory; // path of the executable directory
+extern std::string workingDirectory; // path of the working directory
+}
+
+} // namespace Stockfish