[clang] [CIR] Simplify ConstantOp accesses and its getDefiningOp (PR #151216)

[Henrich Lauko via cfe-commits]

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@@ -291,6 +291,21 @@ def CIR_ConstantOp : CIR_Op<"const", [
         return ptrAttr.isNullValue();
       return false;
     }
+
+    template <typename T>
+    T getValueAttr() { return mlir::dyn_cast<T>(getValue()); }
+
+    llvm::APInt getIntValue() {
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xlauko wrote:

They are in not upstreamed parts of this PR in the incubator, I will drop them for now.

https://github.com/llvm/llvm-project/pull/151216