[PATCH] D129162: [BOLT] Change mutex implementation

[Elvina Yakubova via Phabricator via llvm-commits]

Elvina created this revision.
Elvina added reviewers: yota9, maksfb, rafaelauler.
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Changed acquire implementation to __atomic_test_and_set() and release to __atomic_clear() so it eliminates inline asm usage and is arch independent.

      

Elvina Yakubova,
Advanced Software Technology Lab, Huawei


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D129162

Files:
  bolt/runtime/common.h


Index: bolt/runtime/common.h
===================================================================
--- bolt/runtime/common.h
+++ bolt/runtime/common.h
@@ -470,15 +470,11 @@
 
 /// 1B mutex accessed by lock xchg
 class Mutex {
-  volatile bool InUse{false};
+  volatile bool Result{false};
 
 public:
-  bool acquire() {
-    bool Result = true;
-    asm volatile("lock; xchg %0, %1" : "+m"(InUse), "=r"(Result) : : "cc");
-    return !Result;
-  }
-  void release() { InUse = false; }
+  bool acquire() { return !__atomic_test_and_set(&Result, __ATOMIC_ACQUIRE); }
+  void release() { __atomic_clear(&Result, __ATOMIC_RELEASE); }
 };
 
 /// RAII wrapper for Mutex


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