[llvm] [SLP]Initial support for non-power-of-2 (but still whole register) number of elements in operands. (PR #107273)

[Philip Reames via llvm-commits]

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@@ -4781,12 +4814,13 @@ BoUpSLP::LoadsState BoUpSLP::canVectorizeLoads(
                  });
         });
     const unsigned AbsoluteDiff = std::abs(*Diff);
-    if (IsPossibleStrided && (IsAnyPointerUsedOutGraph ||
-                              ((Sz > MinProfitableStridedLoads ||
-                                (AbsoluteDiff <= MaxProfitableLoadStride * Sz &&
-                                 has_single_bit(AbsoluteDiff))) &&
-                               AbsoluteDiff > Sz) ||
-                              *Diff == -(static_cast<int>(Sz) - 1))) {
+    if (IsPossibleStrided &&
+        (IsAnyPointerUsedOutGraph ||
+         ((Sz > MinProfitableStridedLoads ||
+           (AbsoluteDiff <= MaxProfitableLoadStride * Sz &&
+            hasFullVectorsOnly(*TTI, ScalarTy, AbsoluteDiff))) &&
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preames wrote:

I think you're confusing two things here.  The has_single_bit check was on the size (and thus stride), not on the element type.  I think we can probably just relax this check to allow any stride >= Sz.  

https://github.com/llvm/llvm-project/pull/107273