[llvm] llvm-reduce: Fix losing call metadata in operands-to-args (PR #133422)

[Tim Gymnich via llvm-commits]

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@@ -111,6 +111,8 @@ static void replaceFunctionCalls(Function *OldF, Function *NewF) {
     if (auto *FPOp = dyn_cast<FPMathOperator>(NewCI))
       NewCI->setFastMathFlags(CI->getFastMathFlags());
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tgymnich wrote:

use `isa` instead of `dyn_cast`?

https://github.com/llvm/llvm-project/pull/133422