[clang] [llvm] [BPF] Add load-acquire and store-release instructions under -mcpu=v4 (PR #108636)

[Peilin Ye via cfe-commits]

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@@ -703,6 +714,20 @@ SDValue BPFTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
   return DAG.getNode(BPFISD::SELECT_CC, DL, VTs, Ops);
 }
 
+SDValue BPFTargetLowering::LowerATOMIC_LOAD_STORE(SDValue Op,
+                                                  SelectionDAG &DAG) const {
+  SDNode *N = Op.getNode();
+  SDLoc DL(N);
+
+  if (cast<AtomicSDNode>(N)->getMergedOrdering() ==
+      AtomicOrdering::SequentiallyConsistent)
+    fail(
+        DL, DAG,
+        "sequentially consistent (seq_cst) atomic load/store is not supported");
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peilin-ye wrote:

Got it, thanks!

https://github.com/llvm/llvm-project/pull/108636