Update compiler-rt to LLVM 20.1.4 (#24357)

This updates compiler-rt to LLVM 20.1.4.

Additional change:
- Reflect GetThreadStackAndTls's API change:
a463f5a
In llvm/llvm-project#108883,
`GetThreadStackAndTls`'s API changed from
  ```
  void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
                            uptr *tls_addr, uptr *tls_size);
  ```
  to
  ```
  void GetThreadStackAndTls(bool main, uptr *stk_begin, uptr *stk_end,
                            uptr *tls_begin, uptr *tls_end);
  ```   
So this fixes `sanitizer_emscripten.cpp`'s `GetThreadStackAndTls`
accordingly. Also this changes the variable names to match those of the
header.

Author: aheejin

ChangeLog.md

@@ -20,7 +20,8 @@ See docs/process.md for more on how version tagging works.
 
 4.0.10 (in development)
 ----------------------
-- libcxx and libcxxabi were updated to LLVM 20.1.4. (#24346)
+- libcxx, libcxxabi, and compiler-rt were updated to LLVM 20.1.4. (#24346 and
+  #24357)
 - Emscripten will not longer generate trampoline functions for Wasm exports
   prior to the module being instantiated.  Storing a reference to a Wasm export
   (e.g. `Module['_malloc']`) prior to instantiation will no longer work.  In

system/lib/compiler-rt/include/sanitizer/common_interface_defs.h

@@ -193,6 +193,43 @@ void SANITIZER_CDECL __sanitizer_annotate_double_ended_contiguous_container(
     const void *old_container_beg, const void *old_container_end,
     const void *new_container_beg, const void *new_container_end);
 
+/// Copies memory annotations from a source storage region to a destination
+/// storage region. After the operation, the destination region has the same
+/// memory annotations as the source region, as long as sanitizer limitations
+/// allow it (more bytes may be unpoisoned than in the source region, resulting
+/// in more false negatives, but never false positives). If the source and
+/// destination regions overlap, only the minimal required changes are made to
+/// preserve the correct annotations. Old storage bytes that are not in the new
+/// storage should have the same annotations, as long as sanitizer limitations
+/// allow it.
+///
+/// This function is primarily designed to be used when moving trivially
+/// relocatable objects that may have poisoned memory, making direct copying
+/// problematic under sanitizer. However, this function does not move memory
+/// content itself, only annotations.
+///
+/// A contiguous container is a container that keeps all of its elements in a
+/// contiguous region of memory. The container owns the region of memory
+/// <c>[src_begin, src_end)</c> and <c>[dst_begin, dst_end)</c>. The memory
+/// within these regions may be alternately poisoned and non-poisoned, with
+/// possibly smaller poisoned and unpoisoned regions.
+///
+/// If this function fully poisons a granule, it is marked as "container
+/// overflow".
+///
+/// Argument requirements: The destination container must have the same size as
+/// the source container, which is inferred from the beginning and end of the
+/// source region. Addresses may be granule-unaligned, but this may affect
+/// performance.
+///
+/// \param src_begin Begin of the source container region.
+/// \param src_end End of the source container region.
+/// \param dst_begin Begin of the destination container region.
+/// \param dst_end End of the destination container region.
+void SANITIZER_CDECL __sanitizer_copy_contiguous_container_annotations(
+    const void *src_begin, const void *src_end, const void *dst_begin,
+    const void *dst_end);
+
 /// Returns true if the contiguous container <c>[beg, end)</c> is properly
 /// poisoned.
 ///

system/lib/compiler-rt/include/sanitizer/memprof_interface.h

@@ -47,9 +47,9 @@ void SANITIZER_CDECL __memprof_print_accumulated_stats(void);
 
 /// User-provided default option settings.
 ///
-/// You can provide your own implementation of this function to return a string
-/// containing MemProf runtime options (for example,
-/// <c>verbosity=1:print_stats=1</c>).
+/// You can set these options via the -memprof-runtime-default-options LLVM flag
+/// or you can provide your own implementation of this function. See
+/// memprof_flags.h for more info.
 ///
 /// \returns Default options string.
 const char *SANITIZER_CDECL __memprof_default_options(void);

system/lib/compiler-rt/include/sanitizer/rtsan_interface.h

@@ -0,0 +1,75 @@
+//===-- sanitizer/rtsan_interface.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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of RealtimeSanitizer.
+//
+// Public interface header.
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_RTSAN_INTERFACE_H
+#define SANITIZER_RTSAN_INTERFACE_H
+
+#include <sanitizer/common_interface_defs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif // __cplusplus
+
+// Disable all RTSan error reporting.
+// Must be paired with a call to `__rtsan_enable`
+void SANITIZER_CDECL __rtsan_disable(void);
+
+// Re-enable all RTSan error reporting.
+// Must follow a call to `__rtsan_disable`.
+void SANITIZER_CDECL __rtsan_enable(void);
+
+#ifdef __cplusplus
+} // extern "C"
+
+namespace __rtsan {
+#if defined(__has_feature) && __has_feature(realtime_sanitizer)
+
+class ScopedDisabler {
+public:
+  ScopedDisabler() { __rtsan_disable(); }
+  ~ScopedDisabler() { __rtsan_enable(); }
+
+#if __cplusplus >= 201103L
+  ScopedDisabler(const ScopedDisabler &) = delete;
+  ScopedDisabler &operator=(const ScopedDisabler &) = delete;
+  ScopedDisabler(ScopedDisabler &&) = delete;
+  ScopedDisabler &operator=(ScopedDisabler &&) = delete;
+#else
+private:
+  ScopedDisabler(const ScopedDisabler &);
+  ScopedDisabler &operator=(const ScopedDisabler &);
+#endif // __cplusplus >= 201103L
+};
+
+#else
+
+class ScopedDisabler {
+public:
+  ScopedDisabler() {}
+#if __cplusplus >= 201103L
+  ScopedDisabler(const ScopedDisabler &) = delete;
+  ScopedDisabler &operator=(const ScopedDisabler &) = delete;
+  ScopedDisabler(ScopedDisabler &&) = delete;
+  ScopedDisabler &operator=(ScopedDisabler &&) = delete;
+#else
+private:
+  ScopedDisabler(const ScopedDisabler &);
+  ScopedDisabler &operator=(const ScopedDisabler &);
+#endif // __cplusplus >= 201103L
+};
+
+#endif // defined(__has_feature) && __has_feature(realtime_sanitizer)
+} // namespace __rtsan
+#endif // __cplusplus
+
+#endif // SANITIZER_RTSAN_INTERFACE_H