class ObjectSizeOffsetVisitor
: public InstVisitor<ObjectSizeOffsetVisitor, SizeOffsetType> {
+ typedef DenseMap<const Value*, SizeOffsetType> CacheMapTy;
+
const DataLayout *TD;
const TargetLibraryInfo *TLI;
bool RoundToAlign;
unsigned IntTyBits;
APInt Zero;
- SmallPtrSet<Value*, 8> SeenInsts;
+ CacheMapTy CacheMap;
APInt align(APInt Size, uint64_t Align);
V = V->stripPointerCasts();
if (isa<Instruction>(V) || isa<GEPOperator>(V)) {
- // If we have already seen this instruction, bail out.
- if (!SeenInsts.insert(V))
- return unknown();
-
- SizeOffsetType Ret;
+ // return cached value or insert unknown in cache if size of V was not
+ // computed yet in order to avoid recursions in PHis
+ std::pair<CacheMapTy::iterator, bool> CacheVal =
+ CacheMap.insert(std::make_pair(V, unknown()));
+ if (!CacheVal.second)
+ return CacheVal.first->second;
+
+ SizeOffsetType Result;
if (GEPOperator *GEP = dyn_cast<GEPOperator>(V))
- Ret = visitGEPOperator(*GEP);
+ Result = visitGEPOperator(*GEP);
else
- Ret = visit(cast<Instruction>(*V));
- SeenInsts.erase(V);
- return Ret;
+ Result = visit(cast<Instruction>(*V));
+ return CacheMap[V] = Result;
}
if (Argument *A = dyn_cast<Argument>(V))