//
// Method: getUnsafeAllocsFromABC()
//
// Description:
// Find all memory objects that are both allocated on the stack and are not
// proven to be indexed in a type-safe manner according to the static array
// bounds checking pass.
//
// Notes:
// This method saves its results be remembering the set of DSNodes which are
// both on the stack and potentially indexed in a type-unsafe manner.
//
// FIXME:
// This method only considers unsafe GEP instructions; it does not consider
// unsafe call instructions or other instructions deemed unsafe by the array
// bounds checking pass.
//
void
ConvertUnsafeAllocas::getUnsafeAllocsFromABC(Module & M) {
UnsafeAllocaNodeListBuilder Builder(budsPass, unsafeAllocaNodes);
Builder.visit(M);
#if 0
// Haohui: Disable it right now since nobody using the code
std::map<BasicBlock *,std::set<Instruction*>*> UnsafeGEPMap= abcPass->UnsafeGetElemPtrs;
std::map<BasicBlock *,std::set<Instruction*>*>::const_iterator bCurrent = UnsafeGEPMap.begin(), bEnd = UnsafeGEPMap.end();
for (; bCurrent != bEnd; ++bCurrent) {
std::set<Instruction *> * UnsafeGetElemPtrs = bCurrent->second;
std::set<Instruction *>::const_iterator iCurrent = UnsafeGetElemPtrs->begin(), iEnd = UnsafeGetElemPtrs->end();
for (; iCurrent != iEnd; ++iCurrent) {
if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(*iCurrent)) {
Value *pointerOperand = GEP->getPointerOperand();
DSGraph * TDG = budsPass->getDSGraph(*(GEP->getParent()->getParent()));
DSNode *DSN = TDG->getNodeForValue(pointerOperand).getNode();
//FIXME DO we really need this ? markReachableAllocas(DSN);
if (DSN && DSN->isAllocaNode() && !DSN->isNodeCompletelyFolded()) {
unsafeAllocaNodes.push_back(DSN);
}
} else {
//call instruction add the corresponding *iCurrent->dump();
//FIXME abort();
}
}
}
#endif
}
void visitGetElementPtrInst(GetElementPtrInst &GEP) {
Value *pointerOperand = GEP.getPointerOperand();
DSGraph * TDG = budsPass->getDSGraph(*(GEP.getParent()->getParent()));
DSNode *DSN = TDG->getNodeForValue(pointerOperand).getNode();
//FIXME DO we really need this ? markReachableAllocas(DSN);
if (DSN && DSN->isAllocaNode() && !DSN->isNodeCompletelyFolded()) {
unsafeAllocaNodes.push_back(DSN);
}
}
void
AllButUnreachableFromMemoryHeuristic::AssignToPools (
const DSNodeList_t &NodesToPA,
Function *F, DSGraph* G,
std::vector<OnePool> &ResultPools) {
// Build a set of all nodes that are reachable from another node in the
// graph. Here we ignore scalar nodes that are only globals as they are
// often global pointers to big arrays.
std::set<const DSNode*> ReachableFromMemory;
for (DSGraph::node_iterator I = G->node_begin(), E = G->node_end();
I != E; ++I) {
DSNode *N = I;
#if 0
//
// Ignore nodes that are just globals and not arrays.
//
if (N->isArray() || N->isHeapNode() || N->isAllocaNode() ||
N->isUnknownNode())
#endif
// If a node is marked, all children are too.
if (!ReachableFromMemory.count(N)) {
for (DSNode::iterator NI = N->begin(), E = N->end(); NI != E; ++NI) {
//
// Sometimes this results in a NULL DSNode. Skip it if that is the
// case.
//
if (!(*NI)) continue;
//
// Do a depth-first iteration over the DSGraph starting with this
// child node.
//
for (df_ext_iterator<const DSNode*>
DI = df_ext_begin(*NI, ReachableFromMemory),
E = df_ext_end(*NI, ReachableFromMemory); DI != E; ++DI)
/*empty*/;
}
}
}
// Only pool allocate a node if it is reachable from a memory object (itself
// included).
for (unsigned i = 0, e = NodesToPA.size(); i != e; ++i)
if (ReachableFromMemory.count(NodesToPA[i]))
ResultPools.push_back(OnePool(NodesToPA[i]));
}