[GVN] Fix uninitialized variable warnings. NFCI.

llvm/include/llvm/Transforms/Scalar/GVN.h

@@ -94,7 +94,7 @@ public:
     // value number to the index of Expression in Expressions. We use it
     // instead of a DenseMap because filling such mapping is faster than
     // filling a DenseMap and the compile time is a little better.
-    uint32_t nextExprNumber;
+    uint32_t nextExprNumber = 0;
 
     std::vector<Expression> Expressions;
     std::vector<uint32_t> ExprIdx;
@@ -107,9 +107,9 @@ public:
         DenseMap<std::pair<uint32_t, const BasicBlock *>, uint32_t>;
     PhiTranslateMap PhiTranslateTable;
 
-    AliasAnalysis *AA;
-    MemoryDependenceResults *MD;
-    DominatorTree *DT;
+    AliasAnalysis *AA = nullptr;
+    MemoryDependenceResults *MD = nullptr;
+    DominatorTree *DT = nullptr;
 
     uint32_t nextValueNumber = 1;
 
@@ -155,14 +155,14 @@ private:
   friend class gvn::GVNLegacyPass;
   friend struct DenseMapInfo<Expression>;
 
-  MemoryDependenceResults *MD;
-  DominatorTree *DT;
-  const TargetLibraryInfo *TLI;
-  AssumptionCache *AC;
+  MemoryDependenceResults *MD = nullptr;
+  DominatorTree *DT = nullptr;
+  const TargetLibraryInfo *TLI = nullptr;
+  AssumptionCache *AC = nullptr;
   SetVector<BasicBlock *> DeadBlocks;
-  OptimizationRemarkEmitter *ORE;
-  ImplicitControlFlowTracking *ICF;
-  LoopInfo *LI;
+  OptimizationRemarkEmitter *ORE = nullptr;
+  ImplicitControlFlowTracking *ICF = nullptr;
+  LoopInfo *LI = nullptr;
 
   ValueTable VN;
 

llvm/lib/Transforms/Scalar/GVN.cpp

@@ -112,7 +112,7 @@ static cl::opt<uint32_t> MaxNumDeps(
 
 struct llvm::GVN::Expression {
   uint32_t opcode;
-  Type *type;
+  Type *type = nullptr;
   bool commutative = false;
   SmallVector<uint32_t, 4> varargs;
 
@@ -173,7 +173,7 @@ struct llvm::gvn::AvailableValue {
   PointerIntPair<Value *, 2, ValType> Val;
 
   /// Offset - The byte offset in Val that is interesting for the load query.
-  unsigned Offset;
+  unsigned Offset = 0;
 
   static AvailableValue get(Value *V, unsigned Offset = 0) {
     AvailableValue Res;
@@ -237,7 +237,7 @@ struct llvm::gvn::AvailableValue {
 /// the associated BasicBlock.
 struct llvm::gvn::AvailableValueInBlock {
   /// BB - The basic block in question.
-  BasicBlock *BB;
+  BasicBlock *BB = nullptr;
 
   /// AV - The actual available value
   AvailableValue AV;

llvm/lib/Transforms/Scalar/NewGVN.cpp

@@ -489,11 +489,11 @@ namespace {
 
 class NewGVN {
   Function &F;
-  DominatorTree *DT;
-  const TargetLibraryInfo *TLI;
-  AliasAnalysis *AA;
-  MemorySSA *MSSA;
-  MemorySSAWalker *MSSAWalker;
+  DominatorTree *DT = nullptr;
+  const TargetLibraryInfo *TLI = nullptr;
+  AliasAnalysis *AA = nullptr;
+  MemorySSA *MSSA = nullptr;
+  MemorySSAWalker *MSSAWalker = nullptr;
   const DataLayout &DL;
   std::unique_ptr<PredicateInfo> PredInfo;
 
@@ -505,7 +505,7 @@ class NewGVN {
   const SimplifyQuery SQ;
 
   // Number of function arguments, used by ranking
-  unsigned int NumFuncArgs;
+  unsigned int NumFuncArgs = 0;
 
   // RPOOrdering of basic blocks
   DenseMap<const DomTreeNode *, unsigned> RPOOrdering;
@@ -516,9 +516,9 @@ class NewGVN {
   // startsout in, and represents any value. Being an optimistic analysis,
   // anything in the TOP class has the value TOP, which is indeterminate and
   // equivalent to everything.
-  CongruenceClass *TOPClass;
+  CongruenceClass *TOPClass = nullptr;
   std::vector<CongruenceClass *> CongruenceClasses;
-  unsigned NextCongruenceNum;
+  unsigned NextCongruenceNum = 0;
 
   // Value Mappings.
   DenseMap<Value *, CongruenceClass *> ValueToClass;
@@ -862,7 +862,7 @@ private:
 
   // Debug counter info.  When verifying, we have to reset the value numbering
   // debug counter to the same state it started in to get the same results.
-  int64_t StartingVNCounter;
+  int64_t StartingVNCounter = 0;
 };
 
 } // end anonymous namespace