[PATCH] D78272: [PowerPC] DAG Combine to transform shifts into multiply-high

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added inline comments.


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Comment at: llvm/lib/Target/PowerPC/PPCISelLowering.cpp:15918
+  // performed by the type legalizer.
+  if (Subtarget.isPPC64() && DCI.isBeforeLegalize())
+    if (SDValue MULH = combineShifttoMULH(N, DCI.DAG, *this, Subtarget))
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This doesn't look like the best check for this.
Do we not want this transform in general, is it expected to be pessimizing somewhere?
Then i'd expect it to be a TLI hook.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D78272/new/

https://reviews.llvm.org/D78272