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

[Craig Topper via llvm-commits]

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@@ -26137,14 +26141,16 @@ SDValue DAGCombiner::visitFP_TO_FP16(SDNode *N) {
 }
 
 SDValue DAGCombiner::visitFP16_TO_FP(SDNode *N) {
+  auto Op = N->getOpcode();
+  assert((Op == ISD::FP16_TO_FP || Op == ISD::BF16_TO_FP) &&
+         "opcode should be FP16_TO_FP or BF16_TO_FP.");
   SDValue N0 = N->getOperand(0);
 
   // fold fp16_to_fp(op & 0xffff) -> fp16_to_fp(op)
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topperc wrote:

Update comment for bf16_to_fp too

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