1 files changed, 78 insertions, 0 deletions
diff --git a/contrib/compiler-rt/lib/tsan/rtl/tsan_external.cc b/contrib/compiler-rt/lib/tsan/rtl/tsan_external.cc
new file mode 100644
index 000000000000..dc8ec62322ce
--- /dev/null
+++ b/contrib/compiler-rt/lib/tsan/rtl/tsan_external.cc
@@ -0,0 +1,78 @@
+//===-- tsan_external.cc --------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of ThreadSanitizer (TSan), a race detector.
+//
+//===----------------------------------------------------------------------===//
+#include "tsan_rtl.h"
+
+namespace __tsan {
+
+#define CALLERPC ((uptr)__builtin_return_address(0))
+
+const uptr kMaxTag = 128;  // Limited to 65,536, since MBlock only stores tags
+                           // as 16-bit values, see tsan_defs.h.
+
+const char *registered_tags[kMaxTag];
+static atomic_uint32_t used_tags{1};  // Tag 0 means "no tag". NOLINT
+
+const char *GetObjectTypeFromTag(uptr tag) {
+  if (tag == 0) return nullptr;
+  // Invalid/corrupted tag?  Better return NULL and let the caller deal with it.
+  if (tag >= atomic_load(&used_tags, memory_order_relaxed)) return nullptr;
+  return registered_tags[tag];
+}
+
+extern "C" {
+SANITIZER_INTERFACE_ATTRIBUTE
+void *__tsan_external_register_tag(const char *object_type) {
+  uptr new_tag = atomic_fetch_add(&used_tags, 1, memory_order_relaxed);
+  CHECK_LT(new_tag, kMaxTag);
+  registered_tags[new_tag] = internal_strdup(object_type);
+  return (void *)new_tag;
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_external_assign_tag(void *addr, void *tag) {
+  CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
+  Allocator *a = allocator();
+  MBlock *b = nullptr;
+  if (a->PointerIsMine((void *)addr)) {
+    void *block_begin = a->GetBlockBegin((void *)addr);
+    if (block_begin) b = ctx->metamap.GetBlock((uptr)block_begin);
+  }
+  if (b) {
+    b->tag = (uptr)tag;
+  }
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_external_read(void *addr, void *caller_pc, void *tag) {
+  CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
+  ThreadState *thr = cur_thread();
+  thr->external_tag = (uptr)tag;
+  FuncEntry(thr, (uptr)caller_pc);
+  MemoryRead(thr, CALLERPC, (uptr)addr, kSizeLog8);
+  FuncExit(thr);
+  thr->external_tag = 0;
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_external_write(void *addr, void *caller_pc, void *tag) {
+  CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
+  ThreadState *thr = cur_thread();
+  thr->external_tag = (uptr)tag;
+  FuncEntry(thr, (uptr)caller_pc);
+  MemoryWrite(thr, CALLERPC, (uptr)addr, kSizeLog8);
+  FuncExit(thr);
+  thr->external_tag = 0;
+}
+}  // extern "C"
+
+}  // namespace __tsan