src/hotspot/os_cpu/windows_x86/os_windows_x86.cpp

*** 647,656 ****
--- 647,673 ----
     };
     return 1 ;
  #endif // AMD64
  }
  
+ juint os::cpu_microcode_revision() {
+   juint result = 0;
+   BYTE data[8] = {0};
+   HKEY key;
+   DWORD status = RegOpenKey(HKEY_LOCAL_MACHINE,
+                "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0", &key);
+   if (status == ERROR_SUCCESS) {
+     DWORD size = sizeof(data);
+     status = RegQueryValueEx(key, "Update Revision", NULL, NULL, data, &size);
+     if (status == ERROR_SUCCESS) {
+       if (size == 4) result = *((juint*)data);
+       if (size == 8) result = *((juint*)data + 1); // upper 32-bits
+     }
+     RegCloseKey(key);
+   }
+   return result;
+ }
  
  void os::setup_fpu() {
  #ifndef AMD64
    int fpu_cntrl_word = StubRoutines::fpu_cntrl_wrd_std();
    __asm fldcw fpu_cntrl_word;