[llvm] [profcheck] Add unknown branch weights to expand LL/SR loop. (PR #166273)

[Aiden Grossman via llvm-commits]

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@@ -1295,7 +1295,13 @@ Value *AtomicExpandImpl::insertRMWLLSCLoop(
       TLI->emitStoreConditional(Builder, NewVal, Addr, MemOpOrder);
   Value *TryAgain = Builder.CreateICmpNE(
       StoreSuccess, ConstantInt::get(IntegerType::get(Ctx, 32), 0), "tryagain");
-  Builder.CreateCondBr(TryAgain, LoopBB, ExitBB);
+
+  Instruction *CondBr = Builder.CreateCondBr(TryAgain, LoopBB, ExitBB);
+
+  // Atomic RMW expands to a icmp loop, because it is hard to predict precise
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boomanaiden154 wrote:

This still needs to be updated.

https://github.com/llvm/llvm-project/pull/166273