[llvm] [AArch64][FEAT_CMPBR] Codegen for Armv9.6-a compare-and-branch (PR #116465)

[David Green via llvm-commits]

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@@ -7489,3 +7492,57 @@ bool AArch64DAGToDAGISel::SelectSMETileSlice(SDValue N, unsigned MaxSize,
   Offset = CurDAG->getTargetConstant(0, SDLoc(N), MVT::i64);
   return true;
 }
+
+template <int Bits>
+bool AArch64DAGToDAGISel::SelectCmpBranchUImm6Operand(SDNode *P, SDValue N,
+                                                      SDValue &Imm) {
+  ConstantSDNode *C = dyn_cast<ConstantSDNode>(P->getOperand(1));
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davemgreen wrote:

I think you can assume this is always the case, so rely upon P->getConstantOperandVal(1) (it has an assert inside it).

https://github.com/llvm/llvm-project/pull/116465