[llvm] [VPlan] Move out canNarrowOps (NFC). (PR #167309)

[David Sherwood via llvm-commits]

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@@ -4142,6 +4142,32 @@ static bool canNarrowLoad(VPWidenRecipe *WideMember0, unsigned OpIdx,
   return false;
 }
 
+static bool canNarrowOps(ArrayRef<VPValue *> Ops) {
+  SmallVector<VPValue *> Ops0;
+  auto *WideMember0 = dyn_cast<VPWidenRecipe>(Ops[0]);
+  if (!WideMember0)
+    return false;
+
+  for (unsigned Idx = 0; Idx != WideMember0->getNumOperands(); ++Idx) {
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david-arm wrote:

Where has this extra for loop come from? It wasn't in the original code.

https://github.com/llvm/llvm-project/pull/167309