[llvm] Use DIExpression::foldConstantMath() at the result of an appendOpsToArg() (PR #71721)

[Adrian Prantl via llvm-commits]

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@@ -1774,7 +1774,8 @@ DIExpression *DIExpression::appendOpsToArg(const DIExpression *Expr,
     assert(ArgNo == 0 &&
            "Location Index must be 0 for a non-variadic expression.");
     SmallVector<uint64_t, 8> NewOps(Ops.begin(), Ops.end());
-    return DIExpression::prependOpcodes(Expr, NewOps, StackValue);
+    return DIExpression::prependOpcodes(Expr, NewOps, StackValue)
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adrian-prantl wrote:

Can prependOpcodes return nullptr?

https://github.com/llvm/llvm-project/pull/71721