Add a missing function.

llvm-svn: 110195

1 files changed, 49 insertions, 0 deletions

diff --git a/llvm/lib/Analysis/PointerTracking.cpp b/llvm/lib/Analysis/PointerTracking.cpp
index 142066e42ba..03d3059fdbb 100644
--- a/llvm/lib/Analysis/PointerTracking.cpp
+++ b/llvm/lib/Analysis/PointerTracking.cpp
@@ -144,6 +144,55 @@ const SCEV *PointerTracking::computeAllocationCount(Value *P,
   return SE->getCouldNotCompute();
 }
 
+Value *PointerTracking::computeAllocationCountValue(Value *P, const Type *&Ty) const 
+{
+  Value *V = P->stripPointerCasts();
+  if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
+    Ty = AI->getAllocatedType();
+    // arraySize elements of type Ty.
+    return AI->getArraySize();
+  }
+
+  if (CallInst *CI = extractMallocCall(V)) {
+    Ty = getMallocAllocatedType(CI);
+    if (!Ty)
+      return 0;
+    Value *arraySize = getMallocArraySize(CI, TD);
+    if (!arraySize) {
+      Ty = Type::getInt8Ty(P->getContext());
+      return CI->getArgOperand(0);
+    }
+    // arraySize elements of type Ty.
+    return arraySize;
+  }
+
+  if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V)) {
+    if (GV->hasDefinitiveInitializer()) {
+      Constant *C = GV->getInitializer();
+      if (const ArrayType *ATy = dyn_cast<ArrayType>(C->getType())) {
+        Ty = ATy->getElementType();
+        return ConstantInt::get(Type::getInt32Ty(P->getContext()),
+                               ATy->getNumElements());
+      }
+    }
+    Ty = cast<PointerType>(GV->getType())->getElementType();
+    return ConstantInt::get(Type::getInt32Ty(P->getContext()), 1);
+    //TODO: implement more tracking for globals
+  }
+
+  if (CallInst *CI = dyn_cast<CallInst>(V)) {
+    CallSite CS(CI);
+    Function *F = dyn_cast<Function>(CS.getCalledValue()->stripPointerCasts());
+    if (F == reallocFunc) {
+      Ty = Type::getInt8Ty(P->getContext());
+      // realloc allocates arg1 bytes.
+      return CS.getArgument(1);
+    }
+  }
+
+  return 0;
+}
+
 // Calculates the number of elements of type Ty allocated for P.
 const SCEV *PointerTracking::computeAllocationCountForType(Value *P,
                                                            const Type *Ty)