[llvm] [VPlan] Use SINGLE-SCALAR when printing single-scalar VPInstructions. (PR #141428)

[Luke Lau via llvm-commits]

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@@ -965,7 +965,7 @@ void VPInstruction::dump() const {
 
 void VPInstruction::print(raw_ostream &O, const Twine &Indent,
                           VPSlotTracker &SlotTracker) const {
-  O << Indent << "EMIT ";
+  O << Indent << (isSingleScalar() ? "SINGLE-SCALAR " : "EMIT ");
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lukel97 wrote:

Or print it like a flag, something like `EMIT single-scalar vp<%foo> = ...`

https://github.com/llvm/llvm-project/pull/141428