[llvm] [VPlan] Add VPIRInstruction, use for exit block live-outs. (PR #100735)

[via llvm-commits]

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@@ -1399,6 +1400,45 @@ class VPInstruction : public VPRecipeWithIRFlags {
   bool isSingleScalar() const;
 };
 
+/// A recipe to wrap on original IR instruction not to be modified during
+/// execution, execept for PHIs. For PHIs, a single VPValue operand is allowed,
+/// and it is used to add a new incoming value for the single predecessor VPBB.
+/// Expect PHIs, VPIRInstructions cannot have any operands.
+class VPIRInstruction : public VPRecipeBase {
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ayalz wrote:

Could be a VPSingleDefRecipe, as IR instructions define at most one value, but this currently serves only as a placeholder to advance the insert position, and as a live-out use/operand.

https://github.com/llvm/llvm-project/pull/100735