[PATCH] D95703: [GlobalISel] Propagate extends through G_PHIs into the incoming value blocks.

[Jessica Paquette via Phabricator via llvm-commits]

paquette added inline comments.


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Comment at: llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp:3597
+  SmallPtrSet <MachineInstr*, 4> InSrcs;
+  for (unsigned Idx = 1; Idx < MI.getNumOperands(); Idx += 2)
+    InSrcs.insert(getDefIgnoringCopies(MI.getOperand(Idx).getReg(), MRI));
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aemerson wrote:
> paquette wrote:
> > This can have at most 3 elements before returning false, so I guess you might as well cut the loop short here.
> Unless I'm misunderstanding, this would prevent us from knowing how many unique incoming values there are, if we stop early. G_PHIs can have any number of operands.
Oh, I see. Makes sense.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D95703/new/

https://reviews.llvm.org/D95703