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diff --git a/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_tls_get_addr.h b/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_tls_get_addr.h
new file mode 100644
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+++ b/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_tls_get_addr.h
@@ -0,0 +1,87 @@
+//===-- sanitizer_tls_get_addr.h --------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Handle the __tls_get_addr call.
+//
+// All this magic is specific to glibc and is required to workaround
+// the lack of interface that would tell us about the Dynamic TLS (DTLS).
+// https://sourceware.org/bugzilla/show_bug.cgi?id=16291
+//
+// Before 2.25: every DTLS chunk is allocated with __libc_memalign,
+// which we intercept and thus know where is the DTLS.
+//
+// Since 2.25: DTLS chunks are allocated with malloc. We could co-opt
+// the malloc interceptor to keep track of the last allocation, similar
+// to how we handle __libc_memalign; however, this adds some overhead
+// (since malloc, unlike __libc_memalign, is commonly called), and
+// requires care to avoid false negatives for LeakSanitizer.
+// Instead, we rely on our internal allocators - which keep track of all
+// its allocations - to determine if an address points to a malloc
+// allocation.
+//
+// There exists a since-deprecated version of Google's internal glibc fork
+// that used __signal_safe_memalign. DTLS_on_tls_get_addr relied on a
+// heuristic check (is the allocation 16 bytes from the start of a page
+// boundary?), which was sometimes erroneous:
+//     https://bugs.chromium.org/p/chromium/issues/detail?id=1275223#c15
+// Since that check has no practical use anymore, we have removed it.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_TLS_GET_ADDR_H
+#define SANITIZER_TLS_GET_ADDR_H
+
+#include "sanitizer_atomic.h"
+#include "sanitizer_common.h"
+
+namespace __sanitizer {
+
+struct DTLS {
+  // Array of DTLS chunks for the current Thread.
+  // If beg == 0, the chunk is unused.
+  struct DTV {
+    uptr beg, size;
+  };
+  struct DTVBlock {
+    atomic_uintptr_t next;
+    DTV dtvs[(4096UL - sizeof(next)) / sizeof(DTLS::DTV)];
+  };
+
+  static_assert(sizeof(DTVBlock) <= 4096UL, "Unexpected block size");
+
+  atomic_uintptr_t dtv_block;
+
+  // Auxiliary fields, don't access them outside sanitizer_tls_get_addr.cpp
+  uptr last_memalign_size;
+  uptr last_memalign_ptr;
+};
+
+template <typename Fn>
+void ForEachDVT(DTLS *dtls, const Fn &fn) {
+  DTLS::DTVBlock *block =
+      (DTLS::DTVBlock *)atomic_load(&dtls->dtv_block, memory_order_acquire);
+  while (block) {
+    int id = 0;
+    for (auto &d : block->dtvs) fn(d, id++);
+    block = (DTLS::DTVBlock *)atomic_load(&block->next, memory_order_acquire);
+  }
+}
+
+// Returns pointer and size of a linker-allocated TLS block.
+// Each block is returned exactly once.
+DTLS::DTV *DTLS_on_tls_get_addr(void *arg, void *res, uptr static_tls_begin,
+                                uptr static_tls_end);
+void DTLS_on_libc_memalign(void *ptr, uptr size);
+DTLS *DTLS_Get();
+void DTLS_Destroy();  // Make sure to call this before the thread is destroyed.
+// Returns true if DTLS of suspended thread is in destruction process.
+bool DTLSInDestruction(DTLS *dtls);
+
+}  // namespace __sanitizer
+
+#endif  // SANITIZER_TLS_GET_ADDR_H