-static RegisterAnalysis<ImmediateDominators>
-C("idom", "Immediate Dominators Construction", true);
-static RegisterAnalysis<ImmediatePostDominators>
-D("postidom", "Immediate Post-Dominators Construction", true);
-
-AnalysisID ImmediateDominators::ID = C;
-AnalysisID ImmediatePostDominators::ID = D;
-
-// calcIDoms - Calculate the immediate dominator mapping, given a set of
-// dominators for every basic block.
-void ImmediateDominatorsBase::calcIDoms(const DominatorSetBase &DS) {
- // Loop over all of the nodes that have dominators... figuring out the IDOM
- // for each node...
- //
- for (DominatorSet::const_iterator DI = DS.begin(), DEnd = DS.end();
- DI != DEnd; ++DI) {
- BasicBlock *BB = DI->first;
- const DominatorSet::DomSetType &Dominators = DI->second;
- unsigned DomSetSize = Dominators.size();
- if (DomSetSize == 1) continue; // Root node... IDom = null
-
- // Loop over all dominators of this node. This corresponds to looping over
- // nodes in the dominator chain, looking for a node whose dominator set is
- // equal to the current nodes, except that the current node does not exist
- // in it. This means that it is one level higher in the dom chain than the
- // current node, and it is our idom!
- //
- DominatorSet::DomSetType::const_iterator I = Dominators.begin();
- DominatorSet::DomSetType::const_iterator End = Dominators.end();
- for (; I != End; ++I) { // Iterate over dominators...
- // All of our dominators should form a chain, where the number of elements
- // in the dominator set indicates what level the node is at in the chain.
- // We want the node immediately above us, so it will have an identical
- // dominator set, except that BB will not dominate it... therefore it's
- // dominator set size will be one less than BB's...
- //
- if (DS.getDominators(*I).size() == DomSetSize - 1) {
- IDoms[BB] = *I;
- break;
- }
- }
- }
-}
-
-void ImmediateDominatorsBase::print(std::ostream &o) const {
- for (const_iterator I = begin(), E = end(); I != E; ++I)
- o << "=============================--------------------------------\n"
- << "\nImmediate Dominator For Basic Block\n" << *I->first
- << "is: \n" << *I->second << "\n";
-}