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

[David Green via llvm-commits]

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@@ -400,6 +400,20 @@ def uimm6_32b : Operand<i32>, ImmLeaf<i32, [{ return Imm >= 0 && Imm < 64; }]> {
    let ParserMatchClass = UImm6Operand;
 }
 
+def CmpBranchUImm6Operand_32b
+    : Operand<i32>,
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davemgreen wrote:

This might only need to be a ComplexPattern, not a Operand as well?

Adding `"SelectCmpBranchUImm6Operand<32>", [imm]>` might help a little too, to reduce the number of times the C++ gets called (or at least communicate the intent, even if it is not used).

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