[compiler-rt] 823625c - [nfc][tsan] Simplify morder conversion (#115075)

[via llvm-commits]

Author: Vitaly Buka
Date: 2024-11-05T13:50:46-08:00
New Revision: 823625cf1d9aba4017a486cfdd3e4b9b94c5ef49

URL: https://github.com/llvm/llvm-project/commit/823625cf1d9aba4017a486cfdd3e4b9b94c5ef49
DIFF: https://github.com/llvm/llvm-project/commit/823625cf1d9aba4017a486cfdd3e4b9b94c5ef49.diff

LOG: [nfc][tsan] Simplify morder conversion (#115075)

All valid values should fit into a byte.
This slightly reduce generated code on x86_64.

Added: 
    

Modified: 
    compiler-rt/lib/tsan/rtl/tsan_interface_atomic.cpp

Removed: 
    


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diff  --git a/compiler-rt/lib/tsan/rtl/tsan_interface_atomic.cpp b/compiler-rt/lib/tsan/rtl/tsan_interface_atomic.cpp
index d12e0f596a7fb4..dd37e86ebd7583 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_interface_atomic.cpp
+++ b/compiler-rt/lib/tsan/rtl/tsan_interface_atomic.cpp
@@ -515,7 +515,9 @@ static morder to_morder(int mo) {
   // since we use __sync_ atomics for actual atomic operations,
   // we can safely ignore it as well. It also subtly affects semantics,
   // but we don't model the 
diff erence.
-  return static_cast<morder>(mo & 0x7fff);
+  morder res = static_cast<morder>(static_cast<u8>(mo));
+  DCHECK_LE(res, mo_seq_cst);
+  return res;
 }
 
 #  define ATOMIC_IMPL(func, mo, ...)                                  \