[llvm-branch-commits] [llvm] [LV][REVEC] Initial support for re-vectorisation (PR #208213)

[Gaëtan Bossu via llvm-branch-commits]

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@@ -423,9 +432,13 @@ FixedScalableVFPair VFSelectionContext::computeFeasibleMaxVF(
 
     if (ElementCount::isKnownLE(UserVF, MaxSafeUserVF)) {
       // If `VF=vscale x N` is safe, then so is `VF=N`
-      if (UserVF.isScalable())
-        return FixedScalableVFPair(
-            ElementCount::getFixed(UserVF.getKnownMinValue()), UserVF);
+      // (unless it's wider than MaxSafeFixedVF).
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gbossu wrote:

Higher up, we've restricted `MaxSafeFixedVF`, so this is making sure we aren't overwriting that restriction when the user has chosen a scalable VF.

https://github.com/llvm/llvm-project/pull/208213