[libcxx-commits] [libcxx] [libc++] FreeBSD use fallback for atomic timed wait (PR #180400)

[via libcxx-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-libcxx

Author: Hui (huixie90)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/180400.diff


1 Files Affected:

- (modified) libcxx/src/atomic.cpp (+4-11) 


``````````diff
diff --git a/libcxx/src/atomic.cpp b/libcxx/src/atomic.cpp
index 637c971ed8896..b198cf845f504 100644
--- a/libcxx/src/atomic.cpp
+++ b/libcxx/src/atomic.cpp
@@ -135,17 +135,10 @@ static void __platform_wait_on_address(void const* __ptr, void const* __val, uin
   if (__timeout_ns == 0) {
     _umtx_op(const_cast<void*>(__ptr), UMTX_OP_WAIT, *reinterpret_cast<__cxx_contention_t*>(&buffer), nullptr, nullptr);
   } else {
-    _umtx_time ut;
-    ut._timeout.tv_sec  = __timeout_ns / 1'000'000'000;
-    ut._timeout.tv_nsec = __timeout_ns % 1'000'000'000;
-    ut._flags           = 0;               // Relative time (not absolute)
-    ut._clockid         = CLOCK_MONOTONIC; // Use monotonic clock
-
-    _umtx_op(const_cast<void*>(__ptr),
-             UMTX_OP_WAIT,
-             *reinterpret_cast<__cxx_contention_t*>(&buffer),
-             reinterpret_cast<void*>(sizeof(ut)), // Pass size as uaddr
-             &ut);                                // Pass _umtx_time structure as uaddr2
+    __libcpp_thread_poll_with_backoff(
+        [=]() -> bool { return std::memcmp(const_cast<const void*>(__ptr), __val, _Size) != 0; },
+        __libcpp_timed_backoff_policy(),
+        std::chrono::nanoseconds(__timeout_ns));
   }
 }
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/180400