1 files changed, 38 insertions, 4 deletions
diff --git a/lib/tsan/rtl/tsan_defs.h b/lib/tsan/rtl/tsan_defs.h
index 8a0381e61..3c775debf 100644
--- a/lib/tsan/rtl/tsan_defs.h
+++ b/lib/tsan/rtl/tsan_defs.h
@@ -38,15 +38,40 @@
 
 namespace __tsan {
 
+const int kClkBits = 42;
+const unsigned kMaxTidReuse = (1 << (64 - kClkBits)) - 1;
+
+struct ClockElem {
+  u64 epoch  : kClkBits;
+  u64 reused : 64 - kClkBits;  // tid reuse count
+};
+
+struct ClockBlock {
+  static const uptr kSize = 512;
+  static const uptr kTableSize = kSize / sizeof(u32);
+  static const uptr kClockCount = kSize / sizeof(ClockElem);
+  static const uptr kRefIdx = kTableSize - 1;
+  static const uptr kBlockIdx = kTableSize - 2;
+
+  union {
+    u32       table[kTableSize];
+    ClockElem clock[kClockCount];
+  };
+
+  ClockBlock() {
+  }
+};
+
 const int kTidBits = 13;
-const unsigned kMaxTid = 1 << kTidBits;
+// Reduce kMaxTid by kClockCount because one slot in ClockBlock table is
+// occupied by reference counter, so total number of elements we can store
+// in SyncClock is kClockCount * (kTableSize - 1).
+const unsigned kMaxTid = (1 << kTidBits) - ClockBlock::kClockCount;
 #if !SANITIZER_GO
 const unsigned kMaxTidInClock = kMaxTid * 2;  // This includes msb 'freed' bit.
 #else
 const unsigned kMaxTidInClock = kMaxTid;  // Go does not track freed memory.
 #endif
-const int kClkBits = 42;
-const unsigned kMaxTidReuse = (1 << (64 - kClkBits)) - 1;
 const uptr kShadowStackSize = 64 * 1024;
 
 // Count of shadow values in a shadow cell.
@@ -74,7 +99,7 @@ const bool kCollectHistory = false;
 const bool kCollectHistory = true;
 #endif
 
-const unsigned kInvalidTid = (unsigned)-1;
+const u16 kInvalidTid = kMaxTid + 1;
 
 // The following "build consistency" machinery ensures that all source files
 // are built in the same configuration. Inconsistent builds lead to
@@ -157,6 +182,15 @@ struct MBlock {
 
 COMPILER_CHECK(sizeof(MBlock) == 16);
 
+enum ExternalTag : uptr {
+  kExternalTagNone = 0,
+  kExternalTagSwiftModifyingAccess = 1,
+  kExternalTagFirstUserAvailable = 2,
+  kExternalTagMax = 1024,
+  // Don't set kExternalTagMax over 65,536, since MBlock only stores tags
+  // as 16-bit values, see tsan_defs.h.
+};
+
 }  // namespace __tsan
 
 #endif  // TSAN_DEFS_H