[PATCH] D128342: [LoopVectorize] Disable tail-folding when masked interleaved accesses are unavailable

[Sander de Smalen via Phabricator via llvm-commits]

sdesmalen added inline comments.


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Comment at: llvm/include/llvm/Analysis/VectorUtils.h:814
 
+  bool haveGroups() const { return !InterleaveGroups.empty(); }
+
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nit: s/haveGroups/hasGroups/ ?


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Comment at: llvm/lib/Transforms/Vectorize/LoopVectorize.cpp:5074
+    // on an unpredicated vector loop + scalar epilogue then let's do it now.
+    if (UserVF.isZero() &&
+        ScalarEpilogueStatus == CM_ScalarEpilogueNotNeededUsePredicate) {
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I'm not sure I understand where the `UserVF` comes into play with this choice, given that this a choice between "tail folding" vs "scalar epilogue". Can you elaborate?


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Comment at: llvm/test/Transforms/LoopVectorize/AArch64/sve-tail-folding-interleave.ll:1
+; RUN: opt -loop-vectorize -S -prefer-predicate-over-epilogue=predicate-else-scalar-epilogue \
+; RUN:   -debug < %s 2>%t | FileCheck %s
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Why is this loop still vectorized with a VF of 8?


Repository:
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  https://reviews.llvm.org/D128342/new/

https://reviews.llvm.org/D128342