BasicBlock *Program::takeOwnership(std::unique_ptr<BasicBlock> basicBlock) {
assert(basicBlock != NULL);
BasicBlock *result = basicBlock.get();
basicBlocks_.push_back(std::move(basicBlock));
if (result->address()) {
assert(getBasicBlockStartingAt(*result->address()) == NULL);
start2basicBlock_[*result->address()] = result;
}
return result;
}
/**
* Scan the CFG for finding exit and builds virtual edges with entry and exit.
* For memory-place and time purposes, this method is only called when the CFG
* is used (call to an accessors method).
*/
void CFG::scan(void) {
// Prepare data
typedef HashTable<BasicBlock *, BasicBlock *> map_t;
map_t map;
VectorQueue<BasicBlock *> todo;
todo.put(ent);
// Find all BB
_bbs.add(&_entry);
while(todo) {
BasicBlock *bb = todo.get();
ASSERT(bb);
// second case : calling jump to a function
if(map.exists(bb) || (bb != ent && ENTRY(bb)))
continue;
// build the virtual BB
BasicBlock *vbb = new VirtualBasicBlock(bb);
_bbs.add(vbb);
map.put(bb, vbb);
ASSERTP(map.exists(bb), "not for " << bb->address());
// resolve targets
for(BasicBlock::OutIterator edge(bb); edge; edge++) {
ASSERT(edge->target());
if(edge->kind() != Edge::CALL)
todo.put(edge->target());
}
}
// Relink the BB
BasicBlock *vent = map.get(ent, 0);
ASSERT(vent);
new Edge(&_entry, vent, Edge::VIRTUAL);
for(bbs_t::Iterator vbb(_bbs); vbb; vbb++) {
if(vbb->isEnd())
continue;
BasicBlock *bb = ((VirtualBasicBlock *)*vbb)->bb();
if(bb->isReturn())
new Edge(vbb, &_exit, Edge::VIRTUAL);
for(BasicBlock::OutIterator edge(bb); edge; edge++) {
// A call
if(edge->kind() == Edge::CALL) {
Edge *vedge = new Edge(vbb, edge->target(), Edge::CALL);
vedge->toCall();
}
// Pending edge
else if(!edge->target()) {
new Edge(vbb, 0, edge->kind());
}
// Possibly a not explicit call
else {
ASSERT(edge->target());
BasicBlock *vtarget = map.get(edge->target(), 0);
if(vtarget)
new Edge(vbb, vtarget, edge->kind());
else { // calling jump to a function
Edge *nedge = new Edge(vbb, edge->target(), Edge::CALL);
vbb->flags |= BasicBlock::FLAG_Call;
new Edge(vbb, &_exit, Edge::VIRTUAL);
}
}
}
}
_bbs.add(&_exit);
// Number the BB
for(int i = 0; i < _bbs.length(); i++) {
INDEX(_bbs[i]) = i;
_bbs[i]->_cfg = this;
}
flags |= FLAG_Scanned;
}
