ydb-oss sync: add clang16-rt/ to additionalPathsToCopy

1 files changed, 862 insertions, 0 deletions

diff --git a/contrib/libs/clang16-rt/lib/tsan/rtl/tsan_rtl_report.cpp b/contrib/libs/clang16-rt/lib/tsan/rtl/tsan_rtl_report.cpp
new file mode 100644
index 0000000000..c2cff60e2d
--- /dev/null
+++ b/contrib/libs/clang16-rt/lib/tsan/rtl/tsan_rtl_report.cpp
@@ -0,0 +1,862 @@
+//===-- tsan_rtl_report.cpp -----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_libc.h"
+#include "sanitizer_common/sanitizer_placement_new.h"
+#include "sanitizer_common/sanitizer_stackdepot.h"
+#include "sanitizer_common/sanitizer_common.h"
+#include "sanitizer_common/sanitizer_stacktrace.h"
+#include "tsan_platform.h"
+#include "tsan_rtl.h"
+#include "tsan_suppressions.h"
+#include "tsan_symbolize.h"
+#include "tsan_report.h"
+#include "tsan_sync.h"
+#include "tsan_mman.h"
+#include "tsan_flags.h"
+#include "tsan_fd.h"
+
+namespace __tsan {
+
+using namespace __sanitizer;
+
+static ReportStack *SymbolizeStack(StackTrace trace);
+
+// Can be overriden by an application/test to intercept reports.
+#ifdef TSAN_EXTERNAL_HOOKS
+bool OnReport(const ReportDesc *rep, bool suppressed);
+#else
+SANITIZER_WEAK_CXX_DEFAULT_IMPL
+bool OnReport(const ReportDesc *rep, bool suppressed) {
+  (void)rep;
+  return suppressed;
+}
+#endif
+
+SANITIZER_WEAK_DEFAULT_IMPL
+void __tsan_on_report(const ReportDesc *rep) {
+  (void)rep;
+}
+
+static void StackStripMain(SymbolizedStack *frames) {
+  SymbolizedStack *last_frame = nullptr;
+  SymbolizedStack *last_frame2 = nullptr;
+  for (SymbolizedStack *cur = frames; cur; cur = cur->next) {
+    last_frame2 = last_frame;
+    last_frame = cur;
+  }
+
+  if (last_frame2 == 0)
+    return;
+#if !SANITIZER_GO
+  const char *last = last_frame->info.function;
+  const char *last2 = last_frame2->info.function;
+  // Strip frame above 'main'
+  if (last2 && 0 == internal_strcmp(last2, "main")) {
+    last_frame->ClearAll();
+    last_frame2->next = nullptr;
+  // Strip our internal thread start routine.
+  } else if (last && 0 == internal_strcmp(last, "__tsan_thread_start_func")) {
+    last_frame->ClearAll();
+    last_frame2->next = nullptr;
+    // Strip global ctors init, .preinit_array and main caller.
+  } else if (last && (0 == internal_strcmp(last, "__do_global_ctors_aux") ||
+                      0 == internal_strcmp(last, "__libc_csu_init") ||
+                      0 == internal_strcmp(last, "__libc_start_main"))) {
+    last_frame->ClearAll();
+    last_frame2->next = nullptr;
+  // If both are 0, then we probably just failed to symbolize.
+  } else if (last || last2) {
+    // Ensure that we recovered stack completely. Trimmed stack
+    // can actually happen if we do not instrument some code,
+    // so it's only a debug print. However we must try hard to not miss it
+    // due to our fault.
+    DPrintf("Bottom stack frame is missed\n");
+  }
+#else
+  // The last frame always point into runtime (gosched0, goexit0, runtime.main).
+  last_frame->ClearAll();
+  last_frame2->next = nullptr;
+#endif
+}
+
+ReportStack *SymbolizeStackId(u32 stack_id) {
+  if (stack_id == 0)
+    return 0;
+  StackTrace stack = StackDepotGet(stack_id);
+  if (stack.trace == nullptr)
+    return nullptr;
+  return SymbolizeStack(stack);
+}
+
+static ReportStack *SymbolizeStack(StackTrace trace) {
+  if (trace.size == 0)
+    return 0;
+  SymbolizedStack *top = nullptr;
+  for (uptr si = 0; si < trace.size; si++) {
+    const uptr pc = trace.trace[si];
+    uptr pc1 = pc;
+    // We obtain the return address, but we're interested in the previous
+    // instruction.
+    if ((pc & kExternalPCBit) == 0)
+      pc1 = StackTrace::GetPreviousInstructionPc(pc);
+    SymbolizedStack *ent = SymbolizeCode(pc1);
+    CHECK_NE(ent, 0);
+    SymbolizedStack *last = ent;
+    while (last->next) {
+      last->info.address = pc;  // restore original pc for report
+      last = last->next;
+    }
+    last->info.address = pc;  // restore original pc for report
+    last->next = top;
+    top = ent;
+  }
+  StackStripMain(top);
+
+  auto *stack = New<ReportStack>();
+  stack->frames = top;
+  return stack;
+}
+
+bool ShouldReport(ThreadState *thr, ReportType typ) {
+  // We set thr->suppress_reports in the fork context.
+  // Taking any locking in the fork context can lead to deadlocks.
+  // If any locks are already taken, it's too late to do this check.
+  CheckedMutex::CheckNoLocks();
+  // For the same reason check we didn't lock thread_registry yet.
+  if (SANITIZER_DEBUG)
+    ThreadRegistryLock l(&ctx->thread_registry);
+  if (!flags()->report_bugs || thr->suppress_reports)
+    return false;
+  switch (typ) {
+    case ReportTypeSignalUnsafe:
+      return flags()->report_signal_unsafe;
+    case ReportTypeThreadLeak:
+#if !SANITIZER_GO
+      // It's impossible to join phantom threads
+      // in the child after fork.
+      if (ctx->after_multithreaded_fork)
+        return false;
+#endif
+      return flags()->report_thread_leaks;
+    case ReportTypeMutexDestroyLocked:
+      return flags()->report_destroy_locked;
+    default:
+      return true;
+  }
+}
+
+ScopedReportBase::ScopedReportBase(ReportType typ, uptr tag) {
+  ctx->thread_registry.CheckLocked();
+  rep_ = New<ReportDesc>();
+  rep_->typ = typ;
+  rep_->tag = tag;
+  ctx->report_mtx.Lock();
+}
+
+ScopedReportBase::~ScopedReportBase() {
+  ctx->report_mtx.Unlock();
+  DestroyAndFree(rep_);
+}
+
+void ScopedReportBase::AddStack(StackTrace stack, bool suppressable) {
+  ReportStack **rs = rep_->stacks.PushBack();
+  *rs = SymbolizeStack(stack);
+  (*rs)->suppressable = suppressable;
+}
+
+void ScopedReportBase::AddMemoryAccess(uptr addr, uptr external_tag, Shadow s,
+                                       Tid tid, StackTrace stack,
+                                       const MutexSet *mset) {
+  uptr addr0, size;
+  AccessType typ;
+  s.GetAccess(&addr0, &size, &typ);
+  auto *mop = New<ReportMop>();
+  rep_->mops.PushBack(mop);
+  mop->tid = tid;
+  mop->addr = addr + addr0;
+  mop->size = size;
+  mop->write = !(typ & kAccessRead);
+  mop->atomic = typ & kAccessAtomic;
+  mop->stack = SymbolizeStack(stack);
+  mop->external_tag = external_tag;
+  if (mop->stack)
+    mop->stack->suppressable = true;
+  for (uptr i = 0; i < mset->Size(); i++) {
+    MutexSet::Desc d = mset->Get(i);
+    int id = this->AddMutex(d.addr, d.stack_id);
+    ReportMopMutex mtx = {id, d.write};
+    mop->mset.PushBack(mtx);
+  }
+}
+
+void ScopedReportBase::AddUniqueTid(Tid unique_tid) {
+  rep_->unique_tids.PushBack(unique_tid);
+}
+
+void ScopedReportBase::AddThread(const ThreadContext *tctx, bool suppressable) {
+  for (uptr i = 0; i < rep_->threads.Size(); i++) {
+    if ((u32)rep_->threads[i]->id == tctx->tid)
+      return;
+  }
+  auto *rt = New<ReportThread>();
+  rep_->threads.PushBack(rt);
+  rt->id = tctx->tid;
+  rt->os_id = tctx->os_id;
+  rt->running = (tctx->status == ThreadStatusRunning);
+  rt->name = internal_strdup(tctx->name);
+  rt->parent_tid = tctx->parent_tid;
+  rt->thread_type = tctx->thread_type;
+  rt->stack = 0;
+  rt->stack = SymbolizeStackId(tctx->creation_stack_id);
+  if (rt->stack)
+    rt->stack->suppressable = suppressable;
+}
+
+#if !SANITIZER_GO
+static ThreadContext *FindThreadByTidLocked(Tid tid) {
+  ctx->thread_registry.CheckLocked();
+  return static_cast<ThreadContext *>(
+      ctx->thread_registry.GetThreadLocked(tid));
+}
+
+static bool IsInStackOrTls(ThreadContextBase *tctx_base, void *arg) {
+  uptr addr = (uptr)arg;
+  ThreadContext *tctx = static_cast<ThreadContext*>(tctx_base);
+  if (tctx->status != ThreadStatusRunning)
+    return false;
+  ThreadState *thr = tctx->thr;
+  CHECK(thr);
+  return ((addr >= thr->stk_addr && addr < thr->stk_addr + thr->stk_size) ||
+          (addr >= thr->tls_addr && addr < thr->tls_addr + thr->tls_size));
+}
+
+ThreadContext *IsThreadStackOrTls(uptr addr, bool *is_stack) {
+  ctx->thread_registry.CheckLocked();
+  ThreadContext *tctx =
+      static_cast<ThreadContext *>(ctx->thread_registry.FindThreadContextLocked(
+          IsInStackOrTls, (void *)addr));
+  if (!tctx)
+    return 0;
+  ThreadState *thr = tctx->thr;
+  CHECK(thr);
+  *is_stack = (addr >= thr->stk_addr && addr < thr->stk_addr + thr->stk_size);
+  return tctx;
+}
+#endif
+
+void ScopedReportBase::AddThread(Tid tid, bool suppressable) {
+#if !SANITIZER_GO
+  if (const ThreadContext *tctx = FindThreadByTidLocked(tid))
+    AddThread(tctx, suppressable);
+#endif
+}
+
+int ScopedReportBase::AddMutex(uptr addr, StackID creation_stack_id) {
+  for (uptr i = 0; i < rep_->mutexes.Size(); i++) {
+    if (rep_->mutexes[i]->addr == addr)
+      return rep_->mutexes[i]->id;
+  }
+  auto *rm = New<ReportMutex>();
+  rep_->mutexes.PushBack(rm);
+  rm->id = rep_->mutexes.Size() - 1;
+  rm->addr = addr;
+  rm->stack = SymbolizeStackId(creation_stack_id);
+  return rm->id;
+}
+
+void ScopedReportBase::AddLocation(uptr addr, uptr size) {
+  if (addr == 0)
+    return;
+#if !SANITIZER_GO
+  int fd = -1;
+  Tid creat_tid = kInvalidTid;
+  StackID creat_stack = 0;
+  bool closed = false;
+  if (FdLocation(addr, &fd, &creat_tid, &creat_stack, &closed)) {
+    auto *loc = New<ReportLocation>();
+    loc->type = ReportLocationFD;
+    loc->fd_closed = closed;
+    loc->fd = fd;
+    loc->tid = creat_tid;
+    loc->stack = SymbolizeStackId(creat_stack);
+    rep_->locs.PushBack(loc);
+    AddThread(creat_tid);
+    return;
+  }
+  MBlock *b = 0;
+  uptr block_begin = 0;
+  Allocator *a = allocator();
+  if (a->PointerIsMine((void*)addr)) {
+    block_begin = (uptr)a->GetBlockBegin((void *)addr);
+    if (block_begin)
+      b = ctx->metamap.GetBlock(block_begin);
+  }
+  if (!b)
+    b = JavaHeapBlock(addr, &block_begin);
+  if (b != 0) {
+    auto *loc = New<ReportLocation>();
+    loc->type = ReportLocationHeap;
+    loc->heap_chunk_start = block_begin;
+    loc->heap_chunk_size = b->siz;
+    loc->external_tag = b->tag;
+    loc->tid = b->tid;
+    loc->stack = SymbolizeStackId(b->stk);
+    rep_->locs.PushBack(loc);
+    AddThread(b->tid);
+    return;
+  }
+  bool is_stack = false;
+  if (ThreadContext *tctx = IsThreadStackOrTls(addr, &is_stack)) {
+    auto *loc = New<ReportLocation>();
+    loc->type = is_stack ? ReportLocationStack : ReportLocationTLS;
+    loc->tid = tctx->tid;
+    rep_->locs.PushBack(loc);
+    AddThread(tctx);
+  }
+#endif
+  if (ReportLocation *loc = SymbolizeData(addr)) {
+    loc->suppressable = true;
+    rep_->locs.PushBack(loc);
+    return;
+  }
+}
+
+#if !SANITIZER_GO
+void ScopedReportBase::AddSleep(StackID stack_id) {
+  rep_->sleep = SymbolizeStackId(stack_id);
+}
+#endif
+
+void ScopedReportBase::SetCount(int count) { rep_->count = count; }
+
+void ScopedReportBase::SetSigNum(int sig) { rep_->signum = sig; }
+
+const ReportDesc *ScopedReportBase::GetReport() const { return rep_; }
+
+ScopedReport::ScopedReport(ReportType typ, uptr tag)
+    : ScopedReportBase(typ, tag) {}
+
+ScopedReport::~ScopedReport() {}
+
+// Replays the trace up to last_pos position in the last part
+// or up to the provided epoch/sid (whichever is earlier)
+// and calls the provided function f for each event.
+template <typename Func>
+void TraceReplay(Trace *trace, TracePart *last, Event *last_pos, Sid sid,
+                 Epoch epoch, Func f) {
+  TracePart *part = trace->parts.Front();
+  Sid ev_sid = kFreeSid;
+  Epoch ev_epoch = kEpochOver;
+  for (;;) {
+    DCHECK_EQ(part->trace, trace);
+    // Note: an event can't start in the last element.
+    // Since an event can take up to 2 elements,
+    // we ensure we have at least 2 before adding an event.
+    Event *end = &part->events[TracePart::kSize - 1];
+    if (part == last)
+      end = last_pos;
+    f(kFreeSid, kEpochOver, nullptr);  // notify about part start
+    for (Event *evp = &part->events[0]; evp < end; evp++) {
+      Event *evp0 = evp;
+      if (!evp->is_access && !evp->is_func) {
+        switch (evp->type) {
+          case EventType::kTime: {
+            auto *ev = reinterpret_cast<EventTime *>(evp);
+            ev_sid = static_cast<Sid>(ev->sid);
+            ev_epoch = static_cast<Epoch>(ev->epoch);
+            if (ev_sid == sid && ev_epoch > epoch)
+              return;
+            break;
+          }
+          case EventType::kAccessExt:
+            FALLTHROUGH;
+          case EventType::kAccessRange:
+            FALLTHROUGH;
+          case EventType::kLock:
+            FALLTHROUGH;
+          case EventType::kRLock:
+            // These take 2 Event elements.
+            evp++;
+            break;
+          case EventType::kUnlock:
+            // This takes 1 Event element.
+            break;
+        }
+      }
+      CHECK_NE(ev_sid, kFreeSid);
+      CHECK_NE(ev_epoch, kEpochOver);
+      f(ev_sid, ev_epoch, evp0);
+    }
+    if (part == last)
+      return;
+    part = trace->parts.Next(part);
+    CHECK(part);
+  }
+  CHECK(0);
+}
+
+static void RestoreStackMatch(VarSizeStackTrace *pstk, MutexSet *pmset,
+                              Vector<uptr> *stack, MutexSet *mset, uptr pc,
+                              bool *found) {
+  DPrintf2("    MATCHED\n");
+  *pmset = *mset;
+  stack->PushBack(pc);
+  pstk->Init(&(*stack)[0], stack->Size());
+  stack->PopBack();
+  *found = true;
+}
+
+// Checks if addr1|size1 is fully contained in addr2|size2.
+// We check for fully contained instread of just overlapping
+// because a memory access is always traced once, but can be
+// split into multiple accesses in the shadow.
+static constexpr bool IsWithinAccess(uptr addr1, uptr size1, uptr addr2,
+                                     uptr size2) {
+  return addr1 >= addr2 && addr1 + size1 <= addr2 + size2;
+}
+
+// Replays the trace of slot sid up to the target event identified
+// by epoch/addr/size/typ and restores and returns tid, stack, mutex set
+// and tag for that event. If there are multiple such events, it returns
+// the last one. Returns false if the event is not present in the trace.
+bool RestoreStack(EventType type, Sid sid, Epoch epoch, uptr addr, uptr size,
+                  AccessType typ, Tid *ptid, VarSizeStackTrace *pstk,
+                  MutexSet *pmset, uptr *ptag) {
+  // This function restores stack trace and mutex set for the thread/epoch.
+  // It does so by getting stack trace and mutex set at the beginning of
+  // trace part, and then replaying the trace till the given epoch.
+  DPrintf2("RestoreStack: sid=%u@%u addr=0x%zx/%zu typ=%x\n",
+           static_cast<int>(sid), static_cast<int>(epoch), addr, size,
+           static_cast<int>(typ));
+  ctx->slot_mtx.CheckLocked();  // needed to prevent trace part recycling
+  ctx->thread_registry.CheckLocked();
+  TidSlot *slot = &ctx->slots[static_cast<uptr>(sid)];
+  Tid tid = kInvalidTid;
+  // Need to lock the slot mutex as it protects slot->journal.
+  slot->mtx.CheckLocked();
+  for (uptr i = 0; i < slot->journal.Size(); i++) {
+    DPrintf2("  journal: epoch=%d tid=%d\n",
+             static_cast<int>(slot->journal[i].epoch), slot->journal[i].tid);
+    if (i == slot->journal.Size() - 1 || slot->journal[i + 1].epoch > epoch) {
+      tid = slot->journal[i].tid;
+      break;
+    }
+  }
+  if (tid == kInvalidTid)
+    return false;
+  *ptid = tid;
+  ThreadContext *tctx =
+      static_cast<ThreadContext *>(ctx->thread_registry.GetThreadLocked(tid));
+  Trace *trace = &tctx->trace;
+  // Snapshot first/last parts and the current position in the last part.
+  TracePart *first_part;
+  TracePart *last_part;
+  Event *last_pos;
+  {
+    Lock lock(&trace->mtx);
+    first_part = trace->parts.Front();
+    if (!first_part) {
+      DPrintf2("RestoreStack: tid=%d trace=%p no trace parts\n", tid, trace);
+      return false;
+    }
+    last_part = trace->parts.Back();
+    last_pos = trace->final_pos;
+    if (tctx->thr)
+      last_pos = (Event *)atomic_load_relaxed(&tctx->thr->trace_pos);
+  }
+  DynamicMutexSet mset;
+  Vector<uptr> stack;
+  uptr prev_pc = 0;
+  bool found = false;
+  bool is_read = typ & kAccessRead;
+  bool is_atomic = typ & kAccessAtomic;
+  bool is_free = typ & kAccessFree;
+  DPrintf2("RestoreStack: tid=%d parts=[%p-%p] last_pos=%p\n", tid,
+           trace->parts.Front(), last_part, last_pos);
+  TraceReplay(
+      trace, last_part, last_pos, sid, epoch,
+      [&](Sid ev_sid, Epoch ev_epoch, Event *evp) {
+        if (evp == nullptr) {
+          // Each trace part is self-consistent, so we reset state.
+          stack.Resize(0);
+          mset->Reset();
+          prev_pc = 0;
+          return;
+        }
+        bool match = ev_sid == sid && ev_epoch == epoch;
+        if (evp->is_access) {
+          if (evp->is_func == 0 && evp->type == EventType::kAccessExt &&
+              evp->_ == 0)  // NopEvent
+            return;
+          auto *ev = reinterpret_cast<EventAccess *>(evp);
+          uptr ev_addr = RestoreAddr(ev->addr);
+          uptr ev_size = 1 << ev->size_log;
+          uptr ev_pc =
+              prev_pc + ev->pc_delta - (1 << (EventAccess::kPCBits - 1));
+          prev_pc = ev_pc;
+          DPrintf2("  Access: pc=0x%zx addr=0x%zx/%zu type=%u/%u\n", ev_pc,
+                   ev_addr, ev_size, ev->is_read, ev->is_atomic);
+          if (match && type == EventType::kAccessExt &&
+              IsWithinAccess(addr, size, ev_addr, ev_size) &&
+              is_read == ev->is_read && is_atomic == ev->is_atomic && !is_free)
+            RestoreStackMatch(pstk, pmset, &stack, mset, ev_pc, &found);
+          return;
+        }
+        if (evp->is_func) {
+          auto *ev = reinterpret_cast<EventFunc *>(evp);
+          if (ev->pc) {
+            DPrintf2(" FuncEnter: pc=0x%llx\n", ev->pc);
+            stack.PushBack(ev->pc);
+          } else {
+            DPrintf2(" FuncExit\n");
+            // We don't log pathologically large stacks in each part,
+            // if the stack was truncated we can have more func exits than
+            // entries.
+            if (stack.Size())
+              stack.PopBack();
+          }
+          return;
+        }
+        switch (evp->type) {
+          case EventType::kAccessExt: {
+            auto *ev = reinterpret_cast<EventAccessExt *>(evp);
+            uptr ev_addr = RestoreAddr(ev->addr);
+            uptr ev_size = 1 << ev->size_log;
+            prev_pc = ev->pc;
+            DPrintf2("  AccessExt: pc=0x%llx addr=0x%zx/%zu type=%u/%u\n",
+                     ev->pc, ev_addr, ev_size, ev->is_read, ev->is_atomic);
+            if (match && type == EventType::kAccessExt &&
+                IsWithinAccess(addr, size, ev_addr, ev_size) &&
+                is_read == ev->is_read && is_atomic == ev->is_atomic &&
+                !is_free)
+              RestoreStackMatch(pstk, pmset, &stack, mset, ev->pc, &found);
+            break;
+          }
+          case EventType::kAccessRange: {
+            auto *ev = reinterpret_cast<EventAccessRange *>(evp);
+            uptr ev_addr = RestoreAddr(ev->addr);
+            uptr ev_size =
+                (ev->size_hi << EventAccessRange::kSizeLoBits) + ev->size_lo;
+            uptr ev_pc = RestoreAddr(ev->pc);
+            prev_pc = ev_pc;
+            DPrintf2("  Range: pc=0x%zx addr=0x%zx/%zu type=%u/%u\n", ev_pc,
+                     ev_addr, ev_size, ev->is_read, ev->is_free);
+            if (match && type == EventType::kAccessExt &&
+                IsWithinAccess(addr, size, ev_addr, ev_size) &&
+                is_read == ev->is_read && !is_atomic && is_free == ev->is_free)
+              RestoreStackMatch(pstk, pmset, &stack, mset, ev_pc, &found);
+            break;
+          }
+          case EventType::kLock:
+            FALLTHROUGH;
+          case EventType::kRLock: {
+            auto *ev = reinterpret_cast<EventLock *>(evp);
+            bool is_write = ev->type == EventType::kLock;
+            uptr ev_addr = RestoreAddr(ev->addr);
+            uptr ev_pc = RestoreAddr(ev->pc);
+            StackID stack_id =
+                (ev->stack_hi << EventLock::kStackIDLoBits) + ev->stack_lo;
+            DPrintf2("  Lock: pc=0x%zx addr=0x%zx stack=%u write=%d\n", ev_pc,
+                     ev_addr, stack_id, is_write);
+            mset->AddAddr(ev_addr, stack_id, is_write);
+            // Events with ev_pc == 0 are written to the beginning of trace
+            // part as initial mutex set (are not real).
+            if (match && type == EventType::kLock && addr == ev_addr && ev_pc)
+              RestoreStackMatch(pstk, pmset, &stack, mset, ev_pc, &found);
+            break;
+          }
+          case EventType::kUnlock: {
+            auto *ev = reinterpret_cast<EventUnlock *>(evp);
+            uptr ev_addr = RestoreAddr(ev->addr);
+            DPrintf2("  Unlock: addr=0x%zx\n", ev_addr);
+            mset->DelAddr(ev_addr);
+            break;
+          }
+          case EventType::kTime:
+            // TraceReplay already extracted sid/epoch from it,
+            // nothing else to do here.
+            break;
+        }
+      });
+  ExtractTagFromStack(pstk, ptag);
+  return found;
+}
+
+bool RacyStacks::operator==(const RacyStacks &other) const {
+  if (hash[0] == other.hash[0] && hash[1] == other.hash[1])
+    return true;
+  if (hash[0] == other.hash[1] && hash[1] == other.hash[0])
+    return true;
+  return false;
+}
+
+static bool FindRacyStacks(const RacyStacks &hash) {
+  for (uptr i = 0; i < ctx->racy_stacks.Size(); i++) {
+    if (hash == ctx->racy_stacks[i]) {
+      VPrintf(2, "ThreadSanitizer: suppressing report as doubled (stack)\n");
+      return true;
+    }
+  }
+  return false;
+}
+
+static bool HandleRacyStacks(ThreadState *thr, VarSizeStackTrace traces[2]) {
+  if (!flags()->suppress_equal_stacks)
+    return false;
+  RacyStacks hash;
+  hash.hash[0] = md5_hash(traces[0].trace, traces[0].size * sizeof(uptr));
+  hash.hash[1] = md5_hash(traces[1].trace, traces[1].size * sizeof(uptr));
+  {
+    ReadLock lock(&ctx->racy_mtx);
+    if (FindRacyStacks(hash))
+      return true;
+  }
+  Lock lock(&ctx->racy_mtx);
+  if (FindRacyStacks(hash))
+    return true;
+  ctx->racy_stacks.PushBack(hash);
+  return false;
+}
+
+bool OutputReport(ThreadState *thr, const ScopedReport &srep) {
+  // These should have been checked in ShouldReport.
+  // It's too late to check them here, we have already taken locks.
+  CHECK(flags()->report_bugs);
+  CHECK(!thr->suppress_reports);
+  atomic_store_relaxed(&ctx->last_symbolize_time_ns, NanoTime());
+  const ReportDesc *rep = srep.GetReport();
+  CHECK_EQ(thr->current_report, nullptr);
+  thr->current_report = rep;
+  Suppression *supp = 0;
+  uptr pc_or_addr = 0;
+  for (uptr i = 0; pc_or_addr == 0 && i < rep->mops.Size(); i++)
+    pc_or_addr = IsSuppressed(rep->typ, rep->mops[i]->stack, &supp);
+  for (uptr i = 0; pc_or_addr == 0 && i < rep->stacks.Size(); i++)
+    pc_or_addr = IsSuppressed(rep->typ, rep->stacks[i], &supp);
+  for (uptr i = 0; pc_or_addr == 0 && i < rep->threads.Size(); i++)
+    pc_or_addr = IsSuppressed(rep->typ, rep->threads[i]->stack, &supp);
+  for (uptr i = 0; pc_or_addr == 0 && i < rep->locs.Size(); i++)
+    pc_or_addr = IsSuppressed(rep->typ, rep->locs[i], &supp);
+  if (pc_or_addr != 0) {
+    Lock lock(&ctx->fired_suppressions_mtx);
+    FiredSuppression s = {srep.GetReport()->typ, pc_or_addr, supp};
+    ctx->fired_suppressions.push_back(s);
+  }
+  {
+    bool suppressed = OnReport(rep, pc_or_addr != 0);
+    if (suppressed) {
+      thr->current_report = nullptr;
+      return false;
+    }
+  }
+  PrintReport(rep);
+  __tsan_on_report(rep);
+  ctx->nreported++;
+  if (flags()->halt_on_error)
+    Die();
+  thr->current_report = nullptr;
+  return true;
+}
+
+bool IsFiredSuppression(Context *ctx, ReportType type, StackTrace trace) {
+  ReadLock lock(&ctx->fired_suppressions_mtx);
+  for (uptr k = 0; k < ctx->fired_suppressions.size(); k++) {
+    if (ctx->fired_suppressions[k].type != type)
+      continue;
+    for (uptr j = 0; j < trace.size; j++) {
+      FiredSuppression *s = &ctx->fired_suppressions[k];
+      if (trace.trace[j] == s->pc_or_addr) {
+        if (s->supp)
+          atomic_fetch_add(&s->supp->hit_count, 1, memory_order_relaxed);
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+static bool IsFiredSuppression(Context *ctx, ReportType type, uptr addr) {
+  ReadLock lock(&ctx->fired_suppressions_mtx);
+  for (uptr k = 0; k < ctx->fired_suppressions.size(); k++) {
+    if (ctx->fired_suppressions[k].type != type)
+      continue;
+    FiredSuppression *s = &ctx->fired_suppressions[k];
+    if (addr == s->pc_or_addr) {
+      if (s->supp)
+        atomic_fetch_add(&s->supp->hit_count, 1, memory_order_relaxed);
+      return true;
+    }
+  }
+  return false;
+}
+
+static bool SpuriousRace(Shadow old) {
+  Shadow last(LoadShadow(&ctx->last_spurious_race));
+  return last.sid() == old.sid() && last.epoch() == old.epoch();
+}
+
+void ReportRace(ThreadState *thr, RawShadow *shadow_mem, Shadow cur, Shadow old,
+                AccessType typ0) {
+  CheckedMutex::CheckNoLocks();
+
+  // Symbolizer makes lots of intercepted calls. If we try to process them,
+  // at best it will cause deadlocks on internal mutexes.
+  ScopedIgnoreInterceptors ignore;
+
+  uptr addr = ShadowToMem(shadow_mem);
+  DPrintf("#%d: ReportRace %p\n", thr->tid, (void *)addr);
+  if (!ShouldReport(thr, ReportTypeRace))
+    return;
+  uptr addr_off0, size0;
+  cur.GetAccess(&addr_off0, &size0, nullptr);
+  uptr addr_off1, size1, typ1;
+  old.GetAccess(&addr_off1, &size1, &typ1);
+  if (!flags()->report_atomic_races &&
+      ((typ0 & kAccessAtomic) || (typ1 & kAccessAtomic)) &&
+      !(typ0 & kAccessFree) && !(typ1 & kAccessFree))
+    return;
+  if (SpuriousRace(old))
+    return;
+
+  const uptr kMop = 2;
+  Shadow s[kMop] = {cur, old};
+  uptr addr0 = addr + addr_off0;
+  uptr addr1 = addr + addr_off1;
+  uptr end0 = addr0 + size0;
+  uptr end1 = addr1 + size1;
+  uptr addr_min = min(addr0, addr1);
+  uptr addr_max = max(end0, end1);
+  if (IsExpectedReport(addr_min, addr_max - addr_min))
+    return;
+
+  ReportType rep_typ = ReportTypeRace;
+  if ((typ0 & kAccessVptr) && (typ1 & kAccessFree))
+    rep_typ = ReportTypeVptrUseAfterFree;
+  else if (typ0 & kAccessVptr)
+    rep_typ = ReportTypeVptrRace;
+  else if (typ1 & kAccessFree)
+    rep_typ = ReportTypeUseAfterFree;
+
+  if (IsFiredSuppression(ctx, rep_typ, addr))
+    return;
+
+  VarSizeStackTrace traces[kMop];
+  Tid tids[kMop] = {thr->tid, kInvalidTid};
+  uptr tags[kMop] = {kExternalTagNone, kExternalTagNone};
+
+  ObtainCurrentStack(thr, thr->trace_prev_pc, &traces[0], &tags[0]);
+  if (IsFiredSuppression(ctx, rep_typ, traces[0]))
+    return;
+
+  DynamicMutexSet mset1;
+  MutexSet *mset[kMop] = {&thr->mset, mset1};
+
+  // We need to lock the slot during RestoreStack because it protects
+  // the slot journal.
+  Lock slot_lock(&ctx->slots[static_cast<uptr>(s[1].sid())].mtx);
+  ThreadRegistryLock l0(&ctx->thread_registry);
+  Lock slots_lock(&ctx->slot_mtx);
+  if (SpuriousRace(old))
+    return;
+  if (!RestoreStack(EventType::kAccessExt, s[1].sid(), s[1].epoch(), addr1,
+                    size1, typ1, &tids[1], &traces[1], mset[1], &tags[1])) {
+    StoreShadow(&ctx->last_spurious_race, old.raw());
+    return;
+  }
+
+  if (IsFiredSuppression(ctx, rep_typ, traces[1]))
+    return;
+
+  if (HandleRacyStacks(thr, traces))
+    return;
+
+  // If any of the accesses has a tag, treat this as an "external" race.
+  uptr tag = kExternalTagNone;
+  for (uptr i = 0; i < kMop; i++) {
+    if (tags[i] != kExternalTagNone) {
+      rep_typ = ReportTypeExternalRace;
+      tag = tags[i];
+      break;
+    }
+  }
+
+  ScopedReport rep(rep_typ, tag);
+  for (uptr i = 0; i < kMop; i++)
+    rep.AddMemoryAccess(addr, tags[i], s[i], tids[i], traces[i], mset[i]);
+
+  for (uptr i = 0; i < kMop; i++) {
+    ThreadContext *tctx = static_cast<ThreadContext *>(
+        ctx->thread_registry.GetThreadLocked(tids[i]));
+    rep.AddThread(tctx);
+  }
+
+  rep.AddLocation(addr_min, addr_max - addr_min);
+
+  if (flags()->print_full_thread_history) {
+    const ReportDesc *rep_desc = rep.GetReport();
+    for (uptr i = 0; i < rep_desc->threads.Size(); i++) {
+      Tid parent_tid = rep_desc->threads[i]->parent_tid;
+      if (parent_tid == kMainTid || parent_tid == kInvalidTid)
+        continue;
+      ThreadContext *parent_tctx = static_cast<ThreadContext *>(
+          ctx->thread_registry.GetThreadLocked(parent_tid));
+      rep.AddThread(parent_tctx);
+    }
+  }
+
+#if !SANITIZER_GO
+  if (!((typ0 | typ1) & kAccessFree) &&
+      s[1].epoch() <= thr->last_sleep_clock.Get(s[1].sid()))
+    rep.AddSleep(thr->last_sleep_stack_id);
+#endif
+  OutputReport(thr, rep);
+}
+
+void PrintCurrentStack(ThreadState *thr, uptr pc) {
+  VarSizeStackTrace trace;
+  ObtainCurrentStack(thr, pc, &trace);
+  PrintStack(SymbolizeStack(trace));
+}
+
+// Always inlining PrintCurrentStackSlow, because LocatePcInTrace assumes
+// __sanitizer_print_stack_trace exists in the actual unwinded stack, but
+// tail-call to PrintCurrentStackSlow breaks this assumption because
+// __sanitizer_print_stack_trace disappears after tail-call.
+// However, this solution is not reliable enough, please see dvyukov's comment
+// http://reviews.llvm.org/D19148#406208
+// Also see PR27280 comment 2 and 3 for breaking examples and analysis.
+ALWAYS_INLINE USED void PrintCurrentStackSlow(uptr pc) {
+#if !SANITIZER_GO
+  uptr bp = GET_CURRENT_FRAME();
+  auto *ptrace = New<BufferedStackTrace>();
+  ptrace->Unwind(pc, bp, nullptr, false);
+
+  for (uptr i = 0; i < ptrace->size / 2; i++) {
+    uptr tmp = ptrace->trace_buffer[i];
+    ptrace->trace_buffer[i] = ptrace->trace_buffer[ptrace->size - i - 1];
+    ptrace->trace_buffer[ptrace->size - i - 1] = tmp;
+  }
+  PrintStack(SymbolizeStack(*ptrace));
+#endif
+}
+
+}  // namespace __tsan
+
+using namespace __tsan;
+
+extern "C" {
+SANITIZER_INTERFACE_ATTRIBUTE
+void __sanitizer_print_stack_trace() {
+  PrintCurrentStackSlow(StackTrace::GetCurrentPc());
+}
+}  // extern "C"