[PATCH] D92089: [PowerPC] Materialize i64 constants by enumerated patterns.

[Stefan Pintilie via Phabricator via llvm-commits]

stefanp added a comment.

Thank you for the explanations!
I'm fine with keeping the if conditions looking similar and avoiding too many test changes.

I have one more question related to the patterns.



================
Comment at: llvm/lib/Target/PowerPC/PPCISelDAGToDAG.cpp:899
+  // after rotation.
+  if ((LZ + FO + TO) > 48) {
+    Result = CurDAG->getMachineNode(PPC::LI8, dl, MVT::i64,
----------------
One more question: Isn't this the pattern above just a subset of this one?

```
if ((LZ + TO) > 48) {
 ...
}

if ((LZ + FO + TO) > 48) {
  ...
}
```
They both use only two instructions to materialize the constant. If you delete the first one the second one will also catch all of those cases and be the same number of instructions.


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