[llvm] [LoopVectorize][NFC] Rewrite tests to check output of vplan cost model (PR #113697)

[David Sherwood via llvm-commits]

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@@ -8,15 +8,14 @@ target triple = "aarch64-unknown-linux-gnu"
 
 define void @zext_i8_i16(ptr noalias nocapture readonly %p, ptr noalias nocapture %q, i32 %len) #0 {
 ; CHECK-COST-LABEL: LV: Checking a loop in 'zext_i8_i16'
-; CHECK-COST: LV: Found an estimated cost of 0 for VF 1 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 1 for VF 2 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 1 for VF 4 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 1 for VF 8 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 2 for VF 16 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 1 for VF vscale x 1 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 1 for VF vscale x 2 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 1 for VF vscale x 4 For instruction:   %conv = zext i8 %0 to i32
-; CHECK-COST: LV: Found an estimated cost of 0 for VF vscale x 8 For instruction:   %conv = zext i8 %0 to i32
+; CHECK-COST: Cost of 1 for VF 2: WIDEN-CAST ir<%conv> = zext  ir<%0> to i16
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david-arm wrote:

Ah good point. Looks like I was over eager in deleting the VF=1 case. Yes, at the moment we still use the legacy cost model to calculate the scalar case. I imagine this will get simplified at some point?

https://github.com/llvm/llvm-project/pull/113697