1 files changed, 151 insertions, 2 deletions
diff --git a/libsanitizer/tsan/tsan_trace.h b/libsanitizer/tsan/tsan_trace.h
index 9f2677b..a771ad9 100644
--- a/libsanitizer/tsan/tsan_trace.h
+++ b/libsanitizer/tsan/tsan_trace.h
@@ -13,9 +13,9 @@
 #define TSAN_TRACE_H
 
 #include "tsan_defs.h"
-#include "tsan_mutex.h"
-#include "tsan_stack_trace.h"
+#include "tsan_ilist.h"
 #include "tsan_mutexset.h"
+#include "tsan_stack_trace.h"
 
 namespace __tsan {
 
@@ -68,6 +68,155 @@ struct Trace {
   Trace() : mtx(MutexTypeTrace) {}
 };
 
+namespace v3 {
+
+enum class EventType : u64 {
+  kAccessExt,
+  kAccessRange,
+  kLock,
+  kRLock,
+  kUnlock,
+  kTime,
+};
+
+// "Base" type for all events for type dispatch.
+struct Event {
+  // We use variable-length type encoding to give more bits to some event
+  // types that need them. If is_access is set, this is EventAccess.
+  // Otherwise, if is_func is set, this is EventFunc.
+  // Otherwise type denotes the type.
+  u64 is_access : 1;
+  u64 is_func : 1;
+  EventType type : 3;
+  u64 _ : 59;
+};
+static_assert(sizeof(Event) == 8, "bad Event size");
+
+// Nop event used as padding and does not affect state during replay.
+static constexpr Event NopEvent = {1, 0, EventType::kAccessExt, 0};
+
+// Compressed memory access can represent only some events with PCs
+// close enough to each other. Otherwise we fall back to EventAccessExt.
+struct EventAccess {
+  static constexpr uptr kPCBits = 15;
+
+  u64 is_access : 1;  // = 1
+  u64 is_read : 1;
+  u64 is_atomic : 1;
+  u64 size_log : 2;
+  u64 pc_delta : kPCBits;  // signed delta from the previous memory access PC
+  u64 addr : kCompressedAddrBits;
+};
+static_assert(sizeof(EventAccess) == 8, "bad EventAccess size");
+
+// Function entry (pc != 0) or exit (pc == 0).
+struct EventFunc {
+  u64 is_access : 1;  // = 0
+  u64 is_func : 1;    // = 1
+  u64 pc : 62;
+};
+static_assert(sizeof(EventFunc) == 8, "bad EventFunc size");
+
+// Extended memory access with full PC.
+struct EventAccessExt {
+  u64 is_access : 1;   // = 0
+  u64 is_func : 1;     // = 0
+  EventType type : 3;  // = EventType::kAccessExt
+  u64 is_read : 1;
+  u64 is_atomic : 1;
+  u64 size_log : 2;
+  u64 _ : 11;
+  u64 addr : kCompressedAddrBits;
+  u64 pc;
+};
+static_assert(sizeof(EventAccessExt) == 16, "bad EventAccessExt size");
+
+// Access to a memory range.
+struct EventAccessRange {
+  static constexpr uptr kSizeLoBits = 13;
+
+  u64 is_access : 1;   // = 0
+  u64 is_func : 1;     // = 0
+  EventType type : 3;  // = EventType::kAccessRange
+  u64 is_read : 1;
+  u64 is_free : 1;
+  u64 size_lo : kSizeLoBits;
+  u64 pc : kCompressedAddrBits;
+  u64 addr : kCompressedAddrBits;
+  u64 size_hi : 64 - kCompressedAddrBits;
+};
+static_assert(sizeof(EventAccessRange) == 16, "bad EventAccessRange size");
+
+// Mutex lock.
+struct EventLock {
+  static constexpr uptr kStackIDLoBits = 15;
+
+  u64 is_access : 1;   // = 0
+  u64 is_func : 1;     // = 0
+  EventType type : 3;  // = EventType::kLock or EventType::kRLock
+  u64 pc : kCompressedAddrBits;
+  u64 stack_lo : kStackIDLoBits;
+  u64 stack_hi : sizeof(StackID) * kByteBits - kStackIDLoBits;
+  u64 _ : 3;
+  u64 addr : kCompressedAddrBits;
+};
+static_assert(sizeof(EventLock) == 16, "bad EventLock size");
+
+// Mutex unlock.
+struct EventUnlock {
+  u64 is_access : 1;   // = 0
+  u64 is_func : 1;     // = 0
+  EventType type : 3;  // = EventType::kUnlock
+  u64 _ : 15;
+  u64 addr : kCompressedAddrBits;
+};
+static_assert(sizeof(EventUnlock) == 8, "bad EventUnlock size");
+
+// Time change event.
+struct EventTime {
+  u64 is_access : 1;   // = 0
+  u64 is_func : 1;     // = 0
+  EventType type : 3;  // = EventType::kTime
+  u64 sid : sizeof(Sid) * kByteBits;
+  u64 epoch : kEpochBits;
+  u64 _ : 64 - 5 - sizeof(Sid) * kByteBits - kEpochBits;
+};
+static_assert(sizeof(EventTime) == 8, "bad EventTime size");
+
+struct Trace;
+
+struct TraceHeader {
+  Trace* trace = nullptr;  // back-pointer to Trace containing this part
+  INode trace_parts;       // in Trace::parts
+};
+
+struct TracePart : TraceHeader {
+  static constexpr uptr kByteSize = 256 << 10;
+  static constexpr uptr kSize =
+      (kByteSize - sizeof(TraceHeader)) / sizeof(Event);
+  // TraceAcquire does a fast event pointer overflow check by comparing
+  // pointer into TracePart::events with kAlignment mask. Since TracePart's
+  // are allocated page-aligned, this check detects end of the array
+  // (it also have false positives in the middle that are filtered separately).
+  // This also requires events to be the last field.
+  static constexpr uptr kAlignment = 0xff0;
+  Event events[kSize];
+
+  TracePart() {}
+};
+static_assert(sizeof(TracePart) == TracePart::kByteSize, "bad TracePart size");
+
+struct Trace {
+  Mutex mtx;
+  IList<TraceHeader, &TraceHeader::trace_parts, TracePart> parts;
+  Event* final_pos =
+      nullptr;  // final position in the last part for finished threads
+
+  Trace() : mtx(MutexTypeTrace) {}
+};
+
+}  // namespace v3
+
 }  // namespace __tsan
 
 #endif  // TSAN_TRACE_H