[llvm] BPF: Generate locked insn for __sync_fetch_and_add() with cpu v1/v2 (PR #106494)

[via llvm-commits]

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@@ -806,6 +806,7 @@ class XADD<BPFWidthModifer SizeOp, string OpcodeStr, PatFrag OpNode>
 let Constraints = "$dst = $val" in {
   let Predicates = [BPFNoALU32] in {
     def XADDW : XADD<BPF_W, "u32", atomic_load_add_i32>;
+    def XADDD : XADD<BPF_DW, "u64", atomic_load_add_i64>;
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yonghong-song wrote:

Not sure about this. Let me give a try.

https://github.com/llvm/llvm-project/pull/106494