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

[Florian Hahn via llvm-commits]

================
@@ -405,9 +405,12 @@ static unsigned getVFScaleFactor(VPRecipeBase *R) {
   return 1;
 }
 
-bool VPRegisterUsage::exceedsMaxNumRegs(const TargetTransformInfo &TTI) const {
-  return any_of(MaxLocalUsers, [&TTI](auto &LU) {
-    return LU.second > TTI.getNumberOfRegisters(LU.first);
+bool VPRegisterUsage::exceedsMaxNumRegs(const TargetTransformInfo &TTI,
+                                        unsigned OverrideMaxNumRegs) const {
----------------
fhahn wrote:

This change is independent of updated `shouldCalculateRegPressureForVF`? If so, might have been good to do separately.

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