[llvm] [VPlan] Expand VPWidenIntOrFpInductionRecipe into separate recipes (PR #118638)

[Luke Lau via llvm-commits]

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@@ -261,6 +261,14 @@ class VPBuilder {
         FPBinOp ? FPBinOp->getFastMathFlags() : FastMathFlags()));
   }
 
+  VPInstruction *createSplat(VPValue *Val) {
+    return tryInsertInstruction(new VPInstruction(VPInstruction::Splat, {Val}));
+  }
+
+  VPStepVectorRecipe *createStepVector(Type *Ty) {
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lukel97 wrote:

I tried to create a `VPInstruction::StepVector` but unfortunately it looks like we need a recipe to encode the scalar type, since there's no operands. Unless there's a way to plumb it through the VPInstruction? I think https://github.com/llvm/llvm-project/pull/119284 might have done something similar here by passing through a dummy constant

https://github.com/llvm/llvm-project/pull/118638