[llvm] [DAGCombine] Add DAG optimisation for BF16_TO_FP (PR #69426)

[Simon Pilgrim via llvm-commits]

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@@ -26161,6 +26165,8 @@ SDValue DAGCombiner::visitFP_TO_BF16(SDNode *N) {
   return SDValue();
 }
 
+SDValue DAGCombiner::visitBF16_TO_FP(SDNode *N) { return visitFP16_TO_FP(N); }
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RKSimon wrote:

You should probably add an assert to the start of visitFP16_TO_FP to check that the opcode is BF16_TO_FP or FP16_TO_FP

https://github.com/llvm/llvm-project/pull/69426