[llvm] [LV] Teach LoopVectorizationLegality about struct vector calls (PR #119221)

[David Sherwood via llvm-commits]

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+; RUN: opt < %s -mattr=+sve -passes=loop-vectorize,dce,instcombine -force-vector-interleave=1 -prefer-predicate-over-epilogue=predicate-dont-vectorize -S | FileCheck %s
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david-arm wrote:

Do we really need the `dce,instcombine` passes here? I understand it cleans up the IR, but it can also make it harder to see what's going on. There are two examples where it can be a problem:

1. Somebody changes the output of the loop vectoriser, but it doesn't show up here because the end result after running instcombine is the same. That may not itself be a problem, but it does make it harder to see what effect code changes had on the output.
2. Somebody adds a patch that changes DCE or InstCombine passes and is then surprised to see a loop vectoriser test failing. Effectively this RUN line is testing 3 different passes at once and increases the likelihood of churn in the file.


https://github.com/llvm/llvm-project/pull/119221