[llvm] [NVPTX] Add syncscope support for cmpxchg (PR #140812)

[Alex MacLean via llvm-commits]

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@@ -6317,10 +6317,12 @@ Instruction *NVPTXTargetLowering::emitLeadingFence(IRBuilderBase &Builder,
 
   // Specialize for cmpxchg
   // Emit a fence.sc leading fence for cmpxchg seq_cst which are not emulated
+  SyncScope::ID SSID = cast<AtomicCmpXchgInst>(Inst)->getSyncScopeID();
   if (isReleaseOrStronger(Ord))
     return Ord == AtomicOrdering::SequentiallyConsistent
-               ? Builder.CreateFence(AtomicOrdering::SequentiallyConsistent)
-               : Builder.CreateFence(AtomicOrdering::Release);
+               ? Builder.CreateFence(AtomicOrdering::SequentiallyConsistent,
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AlexMaclean wrote:

Nit: can you push the ternary operator inward so it is the first operand to CreateFence?

https://github.com/llvm/llvm-project/pull/140812