[PATCH] D108619: [DAGCombine] Allow FMA combine with both FMA and FMAD

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


================
Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:13056
+    unsigned Opcode = N.getOpcode();
+    return (HasFMA && Opcode == ISD::FMA) || (HasFMAD && Opcode == ISD::FMAD);
+  };
----------------
Why do you need the HasFMA and HasFMAD checks here? I can see that you don't want to create //new// FMA instructions if FMA is not legal, but I can't see why you wouldn't want to combine existing FMAs.

In other words can this just be `return Opcode == ISD::FMA || Opcode == ISD::FMAD;`?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D108619/new/

https://reviews.llvm.org/D108619