[PATCH] D116886: [M68k] Instruction selection to choose neg x when mul x -1 (Fix issue 48588)

[Douglas Chen via Phabricator via llvm-commits]

dougpuob added inline comments.


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Comment at: llvm/lib/Target/M68k/M68kISelDAGToDAG.cpp:326
+    case ISD::SUB:
+      if (llvm::isNullConstant(U->getOperand(0)))
+        return false;
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myhsu wrote:
> it will be great to add a short description here to explain why you do this.
Sure! it is good.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D116886/new/

https://reviews.llvm.org/D116886