[llvm] [AArch64][ISel] Add support for v8.4a RCpc `ldapur`/`stlur` (PR #67879)

[Antonio Frighetto via llvm-commits]

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@@ -1130,10 +1139,6 @@ bool AArch64DAGToDAGISel::SelectAddrModeUnscaled(SDValue N, unsigned Size,
     return false;
   if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) {
     int64_t RHSC = RHS->getSExtValue();
-    // If the offset is valid as a scaled immediate, don't match here.
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antoniofrighetto wrote:

Does not seem to be the case from running current codegen tests, at the very least.

https://github.com/llvm/llvm-project/pull/67879