1 files changed, 133 insertions, 0 deletions
diff --git a/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_external.cpp b/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_external.cpp
new file mode 100644
index 000000000000..98abff54e2b2
--- /dev/null
+++ b/contrib/llvm-project/compiler-rt/lib/tsan/rtl/tsan_external.cpp
@@ -0,0 +1,133 @@
+//===-- tsan_external.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 "tsan_rtl.h"
+#include "sanitizer_common/sanitizer_ptrauth.h"
+
+#if !SANITIZER_GO
+#  include "tsan_interceptors.h"
+#endif
+
+namespace __tsan {
+
+#define CALLERPC ((uptr)__builtin_return_address(0))
+
+struct TagData {
+  const char *object_type;
+  const char *header;
+};
+
+static TagData registered_tags[kExternalTagMax] = {
+  {},
+  {"Swift variable", "Swift access race"},
+};
+static atomic_uint32_t used_tags{kExternalTagFirstUserAvailable};
+static TagData *GetTagData(uptr tag) {
+  // 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];
+}
+
+const char *GetObjectTypeFromTag(uptr tag) {
+  TagData *tag_data = GetTagData(tag);
+  return tag_data ? tag_data->object_type : nullptr;
+}
+
+const char *GetReportHeaderFromTag(uptr tag) {
+  TagData *tag_data = GetTagData(tag);
+  return tag_data ? tag_data->header : nullptr;
+}
+
+uptr TagFromShadowStackFrame(uptr pc) {
+  uptr tag_count = atomic_load(&used_tags, memory_order_relaxed);
+  void *pc_ptr = (void *)pc;
+  if (pc_ptr < GetTagData(0) || pc_ptr > GetTagData(tag_count - 1))
+    return 0;
+  return (TagData *)pc_ptr - GetTagData(0);
+}
+
+#if !SANITIZER_GO
+
+// We need to track tags for individual memory accesses, but there is no space
+// in the shadow cells for them.  Instead we push/pop them onto the thread
+// traces and ignore the extra tag frames when printing reports.
+static void PushTag(ThreadState *thr, uptr tag) {
+  FuncEntry(thr, (uptr)&registered_tags[tag]);
+}
+static void PopTag(ThreadState *thr) { FuncExit(thr); }
+
+static void ExternalAccess(void *addr, uptr caller_pc, uptr tsan_caller_pc,
+                           void *tag, AccessType typ) {
+  CHECK_LT(tag, atomic_load(&used_tags, memory_order_relaxed));
+  bool in_ignored_lib;
+  if (caller_pc && libignore()->IsIgnored(caller_pc, &in_ignored_lib))
+    return;
+
+  ThreadState *thr = cur_thread();
+  if (caller_pc) FuncEntry(thr, caller_pc);
+  PushTag(thr, (uptr)tag);
+  MemoryAccess(thr, tsan_caller_pc, (uptr)addr, 1, typ);
+  PopTag(thr);
+  if (caller_pc) FuncExit(thr);
+}
+
+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, kExternalTagMax);
+  GetTagData(new_tag)->object_type = internal_strdup(object_type);
+  char header[127] = {0};
+  internal_snprintf(header, sizeof(header), "race on %s", object_type);
+  GetTagData(new_tag)->header = internal_strdup(header);
+  return (void *)new_tag;
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_external_register_header(void *tag, const char *header) {
+  CHECK_GE((uptr)tag, kExternalTagFirstUserAvailable);
+  CHECK_LT((uptr)tag, kExternalTagMax);
+  atomic_uintptr_t *header_ptr =
+      (atomic_uintptr_t *)&GetTagData((uptr)tag)->header;
+  header = internal_strdup(header);
+  char *old_header =
+      (char *)atomic_exchange(header_ptr, (uptr)header, memory_order_seq_cst);
+  Free(old_header);
+}
+
+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) {
+  ExternalAccess(addr, STRIP_PAC_PC(caller_pc), CALLERPC, tag, kAccessRead);
+}
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __tsan_external_write(void *addr, void *caller_pc, void *tag) {
+  ExternalAccess(addr, STRIP_PAC_PC(caller_pc), CALLERPC, tag, kAccessWrite);
+}
+}  // extern "C"
+
+#endif  // !SANITIZER_GO
+
+}  // namespace __tsan