[llvm] [AVR] Refactor MUL/FMUL instruction descriptions (NFC) (PR #156862)

[Ben Shi via llvm-commits]

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@@ -514,7 +514,7 @@ bool AVRDAGToDAGISel::selectMultiplication(llvm::SDNode *N) {
   assert(Type == MVT::i8 && "unexpected value type");
 
   bool isSigned = N->getOpcode() == ISD::SMUL_LOHI;
-  unsigned MachineOp = isSigned ? AVR::MULSRdRr : AVR::MULRdRr;
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benshi001 wrote:

It would be better to keep the original name of `MULSRdRr`, most instructions are named in this tradition.

https://github.com/llvm/llvm-project/pull/156862