[NFC] small rename of private member in InlineCost.cpp

[mtrofin]

Summary

Follow-up from https://reviews.llvm.org/D71733. Also moved an
initialization to the base class, where it belonged in the first place.

[davidxl]

llvm/lib/Analysis/InlineCost.cpp

1940

This is not NFC?

[mtrofin]

llvm/lib/Analysis/InlineCost.cpp

1940

It's NFC because it was executed before in InlineCostCallAnalyzer::onInitializeSROAArg(), which is/was the only current scenario.

[davidxl]

llvm/lib/Analysis/InlineCost.cpp

1940

it is not strictly NFC (in the future) because previously it was called in the overrider function of the derived class, where it is moved to the common path. Is it intended?

[mtrofin]

llvm/lib/Analysis/InlineCost.cpp

1940

Yes, it (that initialization) should have been in the base class in the first place. The removal from the set is also in the base class, which is correct.

[davidxl]

lgtm

llvm/lib/Analysis/InlineCost.cpp

protected:
   /// can cause dramatic shifts in the cost of inlining a function.
   DenseMap<Value *, Constant *> SimplifiedValues;
 
   /// Keep track of the values which map back (through function arguments) to
   /// allocas on the caller stack which could be simplified through SROA.
   DenseMap<Value *, AllocaInst *> SROAArgValues;
 
   /// Keep track of Allocas for which we believe we may get SROA optimization.
-  /// We don't delete entries in SROAArgValue because we still want
-  /// isAllocaDerivedArg to function correctly.
-  DenseSet<AllocaInst *> EnabledSROAArgValues;
+  DenseSet<AllocaInst *> EnabledSROAAllocas;
 
   /// Keep track of values which map to a pointer base and constant offset.
   DenseMap<Value *, std::pair<Value *, APInt>> ConstantOffsetPtrs;
 
   /// Keep track of dead blocks due to the constant arguments.
   SetVector<BasicBlock *> DeadBlocks;
 
   /// The mapping of the blocks to their known unique successors due to the
   /// constant arguments.
   DenseMap<BasicBlock *, BasicBlock *> KnownSuccessors;
 
   /// Model the elimination of repeated loads that is expected to happen
   /// whenever we simplify away the stores that would otherwise cause them to be
   /// loads.
   bool EnableLoadElimination;
   SmallPtrSet<Value *, 16> LoadAddrSet;
 
   AllocaInst *getSROAArgForValueOrNull(Value *V) const {
     auto It = SROAArgValues.find(V);
-    if (It == SROAArgValues.end() ||
-        EnabledSROAArgValues.count(It->second) == 0)
+    if (It == SROAArgValues.end() || EnabledSROAAllocas.count(It->second) == 0)
       return nullptr;
     return It->second;
   }
 
   // Custom simplification helper routines.
   bool isAllocaDerivedArg(Value *V);
   void disableSROAForArg(AllocaInst *SROAArg);
   void disableSROA(Value *V);
class InlineCostCallAnalyzer final : public CallAnalyzer {
   void onCommonInstructionSimplification() override {
     addCost(InlineConstants::InstrCost);
   }
 
   void onInitializeSROAArg(AllocaInst *Arg) override {
     assert(Arg != nullptr &&
            "Should not initialize SROA costs for null value.");
     SROAArgCosts[Arg] = 0;
-    EnabledSROAArgValues.insert(Arg);
   }
 
   void onAggregateSROAUse(AllocaInst *SROAArg) override {
     auto CostIt = SROAArgCosts.find(SROAArg);
     assert(CostIt != SROAArgCosts.end() &&
            "expected this argument to have a cost");
     CostIt->second += InlineConstants::InstrCost;
     SROACostSavings += InlineConstants::InstrCost;

 
 /// Test whether the given value is an Alloca-derived function argument.
 bool CallAnalyzer::isAllocaDerivedArg(Value *V) {
   return SROAArgValues.count(V);
 }
 
 void CallAnalyzer::disableSROAForArg(AllocaInst *SROAArg) {
   onDisableSROA(SROAArg);
-  EnabledSROAArgValues.erase(SROAArg);
+  EnabledSROAAllocas.erase(SROAArg);
   disableLoadElimination();
 }
 /// If 'V' maps to a SROA candidate, disable SROA for it.
 void CallAnalyzer::disableSROA(Value *V) {
   if (auto *SROAArg = getSROAArgForValueOrNull(V)) {
     disableSROAForArg(SROAArg);
   }
 }
for (Function::arg_iterator FAI = F.arg_begin(), FAE = F.arg_end();
     Value *PtrArg = *CAI;
     if (ConstantInt *C = stripAndComputeInBoundsConstantOffsets(PtrArg)) {
       ConstantOffsetPtrs[&*FAI] = std::make_pair(PtrArg, C->getValue());
 
       // We can SROA any pointer arguments derived from alloca instructions.
       if (auto *SROAArg = dyn_cast<AllocaInst>(PtrArg)) {
         SROAArgValues[&*FAI] = SROAArg;
         onInitializeSROAArg(SROAArg);
+        EnabledSROAAllocas.insert(SROAArg);
       }
     }
   }
   NumConstantArgs = SimplifiedValues.size();
   NumConstantOffsetPtrArgs = ConstantOffsetPtrs.size();
   NumAllocaArgs = SROAArgValues.size();
 
   // FIXME: If a caller has multiple calls to a callee, we end up recomputing