[PATCH] D122563: [RISCV] Add DAGCombine to fold base operation and reduction.

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


================
Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:7254
+  if (Opc == ISD::FADD && !N->getFlags().hasAllowReassociation() &&
+      ReduceIdx == 0)
+    return SDValue();
----------------
The ReduceIdx is relevant here. The order of the fadd operands doesn't matter. The reduce operation is before the fadd, we need to know if the fadd can be moved before the reduce.


Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D122563/new/

https://reviews.llvm.org/D122563