[VPlan] Remove no-op addMetadata for VPWidenGEP/VPWidenIntOrFPInd (NFC).

GEPs and truncates should not have any metadata that can be propgated at
the moment, so addMetadata is a no-op. Remove the calls.

This patch also adds assertions to the recipes' constructors, to ensure
no metadata is accidentially dropped.

Author: fhahn

llvm/include/llvm/Analysis/VectorUtils.h

@@ -353,6 +353,14 @@ MDNode *uniteAccessGroups(MDNode *AccGroups1, MDNode *AccGroups2);
 MDNode *intersectAccessGroups(const Instruction *Inst1,
                               const Instruction *Inst2);
 
+/// Add metadata from \p Inst to \p Metadata, if it can be preserved after
+/// vectorization. It can be preserved after vectorization if the kind is one of
+/// [MD_tbaa, MD_alias_scope, MD_noalias, MD_fpmath, MD_nontemporal,
+/// MD_access_group, MD_mmra].
+void getMetadataToPropagate(
+    Instruction *Inst,
+    SmallVectorImpl<std::pair<unsigned, MDNode *>> &Metadata);
+
 /// Specifically, let Kinds = [MD_tbaa, MD_alias_scope, MD_noalias, MD_fpmath,
 /// MD_nontemporal, MD_access_group, MD_mmra].
 /// For K in Kinds, we get the MDNode for K from each of the

llvm/lib/Analysis/VectorUtils.cpp

@@ -986,7 +986,7 @@ MDNode *llvm::intersectAccessGroups(const Instruction *Inst1,
 
 /// Add metadata from \p Inst to \p Metadata, if it can be preserved after
 /// vectorization.
-static void getMetadataToPropagate(
+void llvm::getMetadataToPropagate(
     Instruction *Inst,
     SmallVectorImpl<std::pair<unsigned, MDNode *>> &Metadata) {
   Inst->getAllMetadataOtherThanDebugLoc(Metadata);

llvm/lib/Transforms/Vectorize/VPlan.h

@@ -1505,7 +1505,12 @@ class VPWidenGEPRecipe : public VPRecipeWithIRFlags {
 public:
   template <typename IterT>
   VPWidenGEPRecipe(GetElementPtrInst *GEP, iterator_range<IterT> Operands)
-      : VPRecipeWithIRFlags(VPDef::VPWidenGEPSC, Operands, *GEP) {}
+      : VPRecipeWithIRFlags(VPDef::VPWidenGEPSC, Operands, *GEP) {
+    SmallVector<std::pair<unsigned, MDNode *>> Metadata;
+    (void)Metadata;
+    getMetadataToPropagate(GEP, Metadata);
+    assert(Metadata.empty() && "unexpected metadata on GEP");
+  }
 
   ~VPWidenGEPRecipe() override = default;
 
@@ -1812,6 +1817,11 @@ class VPWidenIntOrFpInductionRecipe : public VPWidenInductionRecipe {
                                Step, IndDesc, DL),
         Trunc(Trunc) {
     addOperand(VF);
+    SmallVector<std::pair<unsigned, MDNode *>> Metadata;
+    (void)Metadata;
+    if (Trunc)
+      getMetadataToPropagate(Trunc, Metadata);
+    assert(Metadata.empty() && "unexpected metadata on Trunc");
   }
 
   ~VPWidenIntOrFpInductionRecipe() override = default;

llvm/lib/Transforms/Vectorize/VPlanRecipes.cpp

@@ -1966,8 +1966,6 @@ void VPWidenIntOrFpInductionRecipe::execute(VPTransformState &State) {
 
   Instruction *LastInduction = cast<Instruction>(
       Builder.CreateBinOp(AddOp, VecInd, SplatVF, "vec.ind.next"));
-  if (isa<TruncInst>(EntryVal))
-    State.addMetadata(LastInduction, EntryVal);
   LastInduction->setDebugLoc(getDebugLoc());
 
   VecInd->addIncoming(SteppedStart, VectorPH);
@@ -2154,7 +2152,6 @@ void VPWidenGEPRecipe::execute(VPTransformState &State) {
                                            getGEPNoWrapFlags());
     Value *Splat = State.Builder.CreateVectorSplat(State.VF, NewGEP);
     State.set(this, Splat);
-    State.addMetadata(Splat, GEP);
   } else {
     // If the GEP has at least one loop-varying operand, we are sure to
     // produce a vector of pointers unless VF is scalar.
@@ -2181,7 +2178,6 @@ void VPWidenGEPRecipe::execute(VPTransformState &State) {
     assert((State.VF.isScalar() || NewGEP->getType()->isVectorTy()) &&
            "NewGEP is not a pointer vector");
     State.set(this, NewGEP);
-    State.addMetadata(NewGEP, GEP);
   }
 }