Add a GetTid() implementation for Windows

llvm-svn: 177927

compiler-rt/lib/sanitizer_common/sanitizer_win.cc

@@ -45,10 +45,16 @@ int GetPid() {
   return GetProcessId(GetCurrentProcess());
 }
 
-uptr GetThreadSelf() {
+// In contrast to POSIX, on Windows GetCurrentThreadId()
+// returns a system-unique identifier.
+uptr GetTid() {
   return GetCurrentThreadId();
 }
 
+uptr GetThreadSelf() {
+  return GetTid();
+}
+
 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
                                 uptr *stack_bottom) {
   CHECK(stack_top);