[PATCH] D75982: [DAGCombine] Respect the uses when combine FMA for a*b+/-c*d

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


================
Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:11923
+  // prefer to fold the multiply with fewer uses.
+  if (Aggressive && isContractableFMUL(N0) && isContractableFMUL(N1) &&
+      (N0.getNode()->use_size() > N1.getNode()->use_size())) {
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steven.zhang wrote:
> lebedev.ri wrote:
> > I'm not sure why `Aggressive && isContractableFMUL(N0) && isContractableFMUL(N1)` check is here?
> > That is already checked in the lambdas.
> Only when both operands(LHS/RHS) are FMUL we should respect the uses to decide on folding which one,  Therefore, we need the check here. 
Err, i mean, why `Aggressive` check is there?


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https://reviews.llvm.org/D75982