!fixup address latest comments, thanks!

Author: fhahn

llvm/lib/Transforms/Vectorize/VPlan.h

@@ -1135,13 +1135,8 @@ class VPPhiAccessors {
   const VPBasicBlock *getIncomingBlock(unsigned Idx) const;
 
   /// Returns the number of incoming values, also number of incoming blocks.
-  /// Note that at the moment, VPWidenIntOrFpInductionRecipes only have a single
-  /// incoming value, its start value.
-  unsigned getNumIncoming() const {
-    const VPRecipeBase *R = getAsRecipe();
-    return R->getVPDefID() == VPDef::VPWidenIntOrFpInductionSC
-               ? 1
-               : getAsRecipe()->getNumOperands();
+  virtual unsigned getNumIncoming() const {
+    return getAsRecipe()->getNumOperands();
   }
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
@@ -1992,6 +1987,11 @@ class VPWidenIntOrFpInductionRecipe : public VPWidenInductionRecipe {
     return isUnrolled() ? getOperand(getNumOperands() - 2) : nullptr;
   }
 
+  /// Returns the number of incoming values, also number of incoming blocks.
+  /// Note that at the moment, VPWidenIntOrFpInductionRecipes only have a single
+  /// incoming value, its start value.
+  unsigned getNumIncoming() const override { return 1; }
+
   /// Returns the first defined value as TruncInst, if it is one or nullptr
   /// otherwise.
   TruncInst *getTruncInst() { return Trunc; }
@@ -3310,9 +3310,6 @@ struct CastInfo<VPPhiAccessors, const VPRecipeBase *>
 
   using Self = CastInfo<VPPhiAccessors, const VPRecipeBase *>;
 
-  using CastReturnType =
-      typename cast_retty<VPPhiAccessors, VPRecipeBase *>::ret_type;
-
   static inline VPPhiAccessors *doCast(const VPRecipeBase *R) {
     return const_cast<VPPhiAccessors *>([R]() -> const VPPhiAccessors * {
       switch (R->getVPDefID()) {
@@ -3328,11 +3325,9 @@ struct CastInfo<VPPhiAccessors, const VPRecipeBase *>
     }());
   }
 
-  static inline VPPhiAccessors *castFailed() { return nullptr; }
-
   static inline VPPhiAccessors *doCastIfPossible(const VPRecipeBase *f) {
     if (!Self::isPossible(f))
-      return castFailed();
+      return nullptr;
     return doCast(f);
   }
 };

llvm/lib/Transforms/Vectorize/VPlanVerifier.cpp

@@ -222,10 +222,10 @@ bool VPlanVerifier::verifyVPBasicBlock(const VPBasicBlock *VPBB) {
         if (auto *Phi = dyn_cast<VPPhiAccessors>(UI)) {
           for (unsigned Idx = 0; Idx != Phi->getNumIncoming(); ++Idx) {
             VPValue *IncVPV = Phi->getIncomingValue(Idx);
-            const VPBasicBlock *IncVPBB = Phi->getIncomingBlock(Idx);
             if (IncVPV != V)
               continue;
-            if (IncVPBB != VPBB && !VPDT.dominates(VPBB, IncVPBB)) {
+            const VPBasicBlock *IncVPBB = Phi->getIncomingBlock(Idx);
+            if (!VPDT.dominates(VPBB, IncVPBB)) {
               errs() << "Incoming def at index " << Idx
                      << " does not dominate incoming block!\n";
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
@@ -240,6 +240,7 @@ bool VPlanVerifier::verifyVPBasicBlock(const VPBasicBlock *VPBB) {
           }
           continue;
         }
+        // TODO: Also verify VPPredInstPHIRecipe.
         if (isa<VPPredInstPHIRecipe>(UI))
           continue;