[llvm] [LoopVectorizer][AArch64] Move getMinTripCountTailFoldingThreshold later. (PR #132170)

[David Sherwood via llvm-commits]

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@@ -1,8 +1,8 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
 ; REQUIRES: asserts
-; RUN: opt -S < %s -p loop-vectorize -debug-only=loop-vectorize -mattr=+sve 2>%t | FileCheck %s --check-prefixes=CHECK,CHECK-VS1
+; RUN: opt -S < %s -p "loop-vectorize,simplifycfg" -debug-only=loop-vectorize -mattr=+sve 2>%t | FileCheck %s --check-prefixes=CHECK,CHECK-VS1
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david-arm wrote:

Do you actually need the `simplifycfg` pass here? If the trip count is 4 and the VF is 4, I'd hope that during vplan construction we optimise the branch in the latch to always exit the loop. Perhaps that might be sufficient to show it working as expected?

https://github.com/llvm/llvm-project/pull/132170