1 files changed, 72 insertions, 0 deletions
diff --git a/lib/libtsan/sanitizer_common/sanitizer_thread_history.cpp b/lib/libtsan/sanitizer_common/sanitizer_thread_history.cpp
new file mode 100644
index 0000000000..0f5bec3ca0
--- /dev/null
+++ b/lib/libtsan/sanitizer_common/sanitizer_thread_history.cpp
@@ -0,0 +1,72 @@
+//===-- sanitizer_thread_history.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
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_thread_history.h"
+
+#include "sanitizer_stackdepot.h"
+namespace __sanitizer {
+
+void PrintThreadHistory(ThreadRegistry &registry, InternalScopedString &out) {
+  ThreadRegistryLock l(&registry);
+  // Stack traces are largest part of printout and they often the same for
+  // multiple threads, so we will deduplicate them.
+  InternalMmapVector<const ThreadContextBase *> stacks;
+
+  registry.RunCallbackForEachThreadLocked(
+      [](ThreadContextBase *context, void *arg) {
+        static_cast<decltype(&stacks)>(arg)->push_back(context);
+      },
+      &stacks);
+
+  Sort(stacks.data(), stacks.size(),
+       [](const ThreadContextBase *a, const ThreadContextBase *b) {
+         if (a->stack_id < b->stack_id)
+           return true;
+         if (a->stack_id > b->stack_id)
+           return false;
+         return a->unique_id < b->unique_id;
+       });
+
+  auto describe_thread = [&](const ThreadContextBase *context) {
+    if (!context) {
+      out.Append("T-1");
+      return;
+    }
+    out.AppendF("T%llu/%llu", context->unique_id, context->os_id);
+    if (internal_strlen(context->name))
+      out.AppendF(" (%s)", context->name);
+  };
+
+  auto get_parent =
+      [&](const ThreadContextBase *context) -> const ThreadContextBase * {
+    if (!context)
+      return nullptr;
+    ThreadContextBase *parent = registry.GetThreadLocked(context->parent_tid);
+    if (!parent)
+      return nullptr;
+    if (parent->unique_id >= context->unique_id)
+      return nullptr;
+    return parent;
+  };
+
+  const ThreadContextBase *prev = nullptr;
+  for (const ThreadContextBase *context : stacks) {
+    if (prev && prev->stack_id != context->stack_id)
+      StackDepotGet(prev->stack_id).PrintTo(&out);
+    prev = context;
+    out.Append("Thread ");
+    describe_thread(context);
+    out.Append(" was created by ");
+    describe_thread(get_parent(context));
+    out.Append("\n");
+  }
+  if (prev)
+    StackDepotGet(prev->stack_id).PrintTo(&out);
+}
+
+}  // namespace __sanitizer