[llvm] [LV] Change loops' interleave count computation (PR #73766)

[David Sherwood via llvm-commits]

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@@ -5737,10 +5741,15 @@ LoopVectorizationCostModel::selectInterleaveCount(ElementCount VF,
   // the InterleaveCount as if vscale is '1', although if some information about
   // the vector is known (e.g. min vector size), we can make a better decision.
   if (BestKnownTC) {
-    MaxInterleaveCount =
-        std::min(*BestKnownTC / VF.getKnownMinValue(), MaxInterleaveCount);
-    // Make sure MaxInterleaveCount is greater than 0.
-    MaxInterleaveCount = std::max(1u, MaxInterleaveCount);
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david-arm wrote:

It's interesting that previously we might have chosen IC to be a non-power-of-2 value!

https://github.com/llvm/llvm-project/pull/73766