[llvm] [LoopIdiomVectorize] Recognize and transform minidx pattern (PR #144987)

[Madhur Amilkanthwar via llvm-commits]

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@@ -0,0 +1,291 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -passes=loop-vectorize -force-vector-width=1 -force-vector-interleave=4 -S %s | FileCheck %s --check-prefix=CHECK-REV-MIN-VW1-IL4
+; RUN: opt -passes=loop-vectorize -force-vector-width=4 -force-vector-interleave=1 -S %s | FileCheck %s --check-prefix=CHECK-REV-MIN-VW4-IL1
+; RUN: opt -passes=loop-vectorize -force-vector-width=4 -force-vector-interleave=2 -S %s | FileCheck %s --check-prefix=CHECK-REV-MIN-VW4-IL2
+; RUN: opt -passes=loop-idiom-vectorize -S -mtriple=aarch64 -mattr=+sve %s | FileCheck %s --check-prefix=CHECK-LOOP-IDIOM
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madhur13490 wrote:

Thanks for the review. I have moved the test. As far as I understand from the discussion on [Discourse](https://discourse.llvm.org/t/vectorizing-min-max-reduction-pattern/85766) I don't think there is any plan to tackle this *complicated* pattern in VPlan. If there is any change in the plan since we last discussed, I would like to know. CC @fhahn @Mel-Chen 

https://github.com/llvm/llvm-project/pull/144987