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

[David Green 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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davemgreen wrote:

It was added to clean up the test output and make it clearer what was changing / important. It shows how much better the code can be if it gets unrolled. Considering this is a heuristic change and not a correctness change that sounded like the better trade-off. It is similar in concept to filter-out-after from #129739 but it doesn't remove any of the output code, just shows how it simplifies after constant branches are folded away.

My understanding of patches over the last little while, these might be optimizations that vplan learns to make itself eventually, and the simplify-cfg will not be useful. It will itself remove the unnecessary branches and the tests will be simpler again. I don't have a strong opinion in the meantime so am happy to remove it.

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