[NFC] Move findAllocaForValue into ValueTracking.h

llvm/include/llvm/Analysis/ValueTracking.h

 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/Operator.h"
 #include <cassert>
 #include <cstdint>
 
 namespace llvm {
 
 class AddOperator;
+class AllocaInst;
 class APInt;
 class AssumptionCache;
 class DominatorTree;
 class GEPOperator;
 class IntrinsicInst;
 class LoadInst;
 class WithOverflowInst;
 struct KnownBits;
void GetUnderlyingObjects(const Value *V,
                             unsigned MaxLookup = 6);
 
   /// This is a wrapper around GetUnderlyingObjects and adds support for basic
   /// ptrtoint+arithmetic+inttoptr sequences.
   bool getUnderlyingObjectsForCodeGen(const Value *V,
                             SmallVectorImpl<Value *> &Objects,
                             const DataLayout &DL);
 
+  /// Finds alloca where the value comes from.
+  AllocaInst *
+  findAllocaForValue(Value *V, DenseMap<Value *, AllocaInst *> &AllocaForValue);
+
   /// Return true if the only users of this pointer are lifetime markers.
   bool onlyUsedByLifetimeMarkers(const Value *V);
 
   /// Return true if the only users of this pointer are lifetime markers or
   /// droppable instructions.
   bool onlyUsedByLifetimeMarkersOrDroppableInsts(const Value *V);
 
   /// Return true if speculation of the given load must be suppressed to avoid

llvm/include/llvm/Transforms/Utils/Local.h

 /// Replaces multiple llvm.dbg.value instructions when the alloca it describes
 /// is replaced with a new value. If Offset is non-zero, a constant displacement
 /// is added to the expression (after the mandatory Deref). Offset can be
 /// negative. New llvm.dbg.value instructions are inserted at the locations of
 /// the instructions they replace.
 void replaceDbgValueForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
                               DIBuilder &Builder, int Offset = 0);
 
-/// Finds alloca where the value comes from.
-AllocaInst *findAllocaForValue(Value *V,
-                               DenseMap<Value *, AllocaInst *> &AllocaForValue);
-
 /// Assuming the instruction \p I is going to be deleted, attempt to salvage
 /// debug users of \p I by writing the effect of \p I in a DIExpression. If it
 /// cannot be salvaged changes its debug uses to undef.
 void salvageDebugInfo(Instruction &I);
 
 
 /// Implementation of salvageDebugInfo, applying only to instructions in
 /// \p Insns, rather than all debug users from findDbgUsers( \p I).

llvm/lib/Analysis/ValueTracking.cpp

for (const Value *V : Objs) {
         return false;
       }
       Objects.push_back(const_cast<Value *>(V));
     }
   } while (!Working.empty());
   return true;
 }
 
+AllocaInst *
+llvm::findAllocaForValue(Value *V,
+                         DenseMap<Value *, AllocaInst *> &AllocaForValue) {
+  if (AllocaInst *AI = dyn_cast<AllocaInst>(V))
+    return AI;
+  // See if we've already calculated (or started to calculate) alloca for a
+  // given value.
+  auto I = AllocaForValue.find(V);
+  if (I != AllocaForValue.end())
+    return I->second;
+  // Store 0 while we're calculating alloca for value V to avoid
+  // infinite recursion if the value references itself.
+  AllocaForValue[V] = nullptr;
+  AllocaInst *Res = nullptr;
+  if (CastInst *CI = dyn_cast<CastInst>(V))
+    Res = findAllocaForValue(CI->getOperand(0), AllocaForValue);
+  else if (PHINode *PN = dyn_cast<PHINode>(V)) {
+    for (Value *IncValue : PN->incoming_values()) {
+      // Allow self-referencing phi-nodes.
+      if (IncValue == PN)
+        continue;
+      AllocaInst *IncValueAI = findAllocaForValue(IncValue, AllocaForValue);
+      // AI for incoming values should exist and should all be equal.
+      if (IncValueAI == nullptr || (Res != nullptr && IncValueAI != Res))
+        return nullptr;
+      Res = IncValueAI;
+    }
+  } else if (GetElementPtrInst *EP = dyn_cast<GetElementPtrInst>(V)) {
+    Res = findAllocaForValue(EP->getPointerOperand(), AllocaForValue);
+  }
+  if (Res)
+    AllocaForValue[V] = Res;
+  return Res;
+}
+
 static bool onlyUsedByLifetimeMarkersOrDroppableInstsHelper(
     const Value *V, bool AllowLifetime, bool AllowDroppable) {
   for (const User *U : V->users()) {
     const IntrinsicInst *II = dyn_cast<IntrinsicInst>(U);
     if (!II)
       return false;
 
     if (AllowLifetime && II->isLifetimeStartOrEnd())

llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp

 #include "llvm/ADT/DepthFirstIterator.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/IR/Argument.h"
 #include "llvm/IR/Attributes.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/CallingConv.h"
 #include "llvm/IR/Constant.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/DerivedTypes.h"

llvm/lib/Transforms/Utils/Local.cpp

case Instruction::GetElementPtr:
     gep_type_iterator It = gep_type_begin(I);
     for (auto E = std::next(It, OpIdx); It != E; ++It)
       if (It.isStruct())
         return false;
     return true;
   }
 }
 
-using AllocaForValueMapTy = DenseMap<Value *, AllocaInst *>;
-AllocaInst *llvm::findAllocaForValue(Value *V,
-                                     AllocaForValueMapTy &AllocaForValue) {
-  if (AllocaInst *AI = dyn_cast<AllocaInst>(V))
-    return AI;
-  // See if we've already calculated (or started to calculate) alloca for a
-  // given value.
-  AllocaForValueMapTy::iterator I = AllocaForValue.find(V);
-  if (I != AllocaForValue.end())
-    return I->second;
-  // Store 0 while we're calculating alloca for value V to avoid
-  // infinite recursion if the value references itself.
-  AllocaForValue[V] = nullptr;
-  AllocaInst *Res = nullptr;
-  if (CastInst *CI = dyn_cast<CastInst>(V))
-    Res = findAllocaForValue(CI->getOperand(0), AllocaForValue);
-  else if (PHINode *PN = dyn_cast<PHINode>(V)) {
-    for (Value *IncValue : PN->incoming_values()) {
-      // Allow self-referencing phi-nodes.
-      if (IncValue == PN)
-        continue;
-      AllocaInst *IncValueAI = findAllocaForValue(IncValue, AllocaForValue);
-      // AI for incoming values should exist and should all be equal.
-      if (IncValueAI == nullptr || (Res != nullptr && IncValueAI != Res))
-        return nullptr;
-      Res = IncValueAI;
-    }
-  } else if (GetElementPtrInst *EP = dyn_cast<GetElementPtrInst>(V)) {
-    Res = findAllocaForValue(EP->getPointerOperand(), AllocaForValue);
-  } else {
-    LLVM_DEBUG(dbgs() << "Alloca search cancelled on unknown instruction: "
-                      << *V << "\n");
-  }
-  if (Res)
-    AllocaForValue[V] = Res;
-  return Res;
-}
-
 Value *llvm::invertCondition(Value *Condition) {
   // First: Check if it's a constant
   if (Constant *C = dyn_cast<Constant>(Condition))
     return ConstantExpr::getNot(C);
 
   // Second: If the condition is already inverted, return the original value
   Value *NotCondition;
   if (match(Condition, m_Not(m_Value(NotCondition))))