[llvm] [LV][AArch64] Prefer epilogue with fixed-width over scalable VF in case of equal costs. (PR #155546)

[Florian Hahn via llvm-commits]

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@@ -10,7 +10,7 @@ target triple = "aarch64-unknown-linux-gnu"
 define void @foo(ptr noalias nocapture readonly %p, ptr noalias nocapture %q, i64 %len) #0 {
 ; CHECK-EPILOG:      vec.epilog.ph:
 ; CHECK-EPILOG:      vec.epilog.vector.body:
-; CHECK-EPILOG:        load <vscale x 4 x i16>
+; CHECK-EPILOG:        load <8 x i16>
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fhahn wrote:

Is the new line relevant for all run lines here? It may be better to have a new test file with a function where the cost of fixed & scalable is the same, which has a comment with a brief explanation and run lines with both the option on and off.

With the changes where its difficult to see if this is working as expected.

https://github.com/llvm/llvm-project/pull/155546