[llvm] [LoopVectorizer] Only check register pressure for VFs that have been enabled via maxBandwidth (PR #149056)

[Nicholas Guy via llvm-commits]

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@@ -4375,9 +4389,10 @@ VectorizationFactor LoopVectorizationPlanner::selectVectorizationFactor() {
       if (VF.isScalar())
         continue;
 
-      /// Don't consider the VF if it exceeds the number of registers for the
-      /// target.
-      if (CM.useMaxBandwidth(VF) && RUs[I].exceedsMaxNumRegs(TTI))
+      /// If the VF was proposed due to MaxBandwidth, don't consider the VF if
+      /// it exceeds the number of registers for the target.
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NickGuy-Arm wrote:

Done, https://github.com/llvm/llvm-project/pull/149478

https://github.com/llvm/llvm-project/pull/149056