[llvm] [VPlan] Add VPValue for VF, use it for VPWidenIntOrFpInductionRecipe. (PR #95305)

[Florian Hahn via llvm-commits]

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@@ -73,7 +74,8 @@ define void @induction_i3_zext(ptr %dst) #0 {
 ; CHECK:       vector.ph:
 ; CHECK:         %ind.end = trunc i64 %n.vec to i3
 ; CHECK-NEXT:    [[TMP4:%.*]] = call i64 @llvm.vscale.i64()
-; CHECK-NEXT:    [[TMP5:%.*]] = mul i64 [[TMP4]], 4
+; CHECK-NEXT:    [[TMP40:%.*]] = mul i64 [[TMP4]], 2
+; CHECK-NEXT:    [[TMP5:%.*]] = mul i64 [[TMP40]], 2
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fhahn wrote:

The reason this was showing up as net increase was that the test case originally didn't check all instructions in vector.ph; now that it does we safe vscale & mul but need a trunc, so it is neutral overall in this case.

https://github.com/llvm/llvm-project/pull/95305