diff options
Diffstat (limited to 'lib/VMCore')
-rw-r--r-- | lib/VMCore/Dominators.cpp | 123 |
1 files changed, 14 insertions, 109 deletions
diff --git a/lib/VMCore/Dominators.cpp b/lib/VMCore/Dominators.cpp index 9bd51bf..4988049 100644 --- a/lib/VMCore/Dominators.cpp +++ b/lib/VMCore/Dominators.cpp @@ -251,113 +251,6 @@ void ImmediateDominatorsBase::print(std::ostream &o, const Module* ) const { o << "\n"; } - - -//===----------------------------------------------------------------------===// -// DominatorSet Implementation -//===----------------------------------------------------------------------===// - -static RegisterPass<DominatorSet> -B("domset", "Dominator Set Construction", true); - -// dominates - Return true if A dominates B. This performs the special checks -// necessary if A and B are in the same basic block. -// -bool DominatorSetBase::dominates(Instruction *A, Instruction *B) const { - BasicBlock *BBA = A->getParent(), *BBB = B->getParent(); - if (BBA != BBB) return dominates(BBA, BBB); - - // It is not possible to determine dominance between two PHI nodes - // based on their ordering. - if (isa<PHINode>(A) && isa<PHINode>(B)) - return false; - - // Loop through the basic block until we find A or B. - BasicBlock::iterator I = BBA->begin(); - for (; &*I != A && &*I != B; ++I) /*empty*/; - - if(!IsPostDominators) { - // A dominates B if it is found first in the basic block. - return &*I == A; - } else { - // A post-dominates B if B is found first in the basic block. - return &*I == B; - } -} - - -// runOnFunction - This method calculates the forward dominator sets for the -// specified function. -// -bool DominatorSet::runOnFunction(Function &F) { - BasicBlock *Root = &F.getEntryBlock(); - Roots.clear(); - Roots.push_back(Root); - assert(pred_begin(Root) == pred_end(Root) && - "Root node has predecessors in function!"); - - ImmediateDominators &ID = getAnalysis<ImmediateDominators>(); - Doms.clear(); - if (Roots.empty()) return false; - - // Root nodes only dominate themselves. - for (unsigned i = 0, e = Roots.size(); i != e; ++i) - Doms[Roots[i]].insert(Roots[i]); - - // Loop over all of the blocks in the function, calculating dominator sets for - // each function. - for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I) - if (BasicBlock *IDom = ID[I]) { // Get idom if block is reachable - DomSetType &DS = Doms[I]; - assert(DS.empty() && "Domset already filled in for this block?"); - DS.insert(I); // Blocks always dominate themselves - - // Insert all dominators into the set... - while (IDom) { - // If we have already computed the dominator sets for our immediate - // dominator, just use it instead of walking all the way up to the root. - DomSetType &IDS = Doms[IDom]; - if (!IDS.empty()) { - DS.insert(IDS.begin(), IDS.end()); - break; - } else { - DS.insert(IDom); - IDom = ID[IDom]; - } - } - } else { - // Ensure that every basic block has at least an empty set of nodes. This - // is important for the case when there is unreachable blocks. - Doms[I]; - } - - return false; -} - -namespace llvm { -static std::ostream &operator<<(std::ostream &o, - const std::set<BasicBlock*> &BBs) { - for (std::set<BasicBlock*>::const_iterator I = BBs.begin(), E = BBs.end(); - I != E; ++I) - if (*I) - WriteAsOperand(o, *I, false); - else - o << " <<exit node>>"; - return o; -} -} - -void DominatorSetBase::print(std::ostream &o, const Module* ) const { - for (const_iterator I = begin(), E = end(); I != E; ++I) { - o << " DomSet For BB: "; - if (I->first) - WriteAsOperand(o, I->first, false); - else - o << " <<exit node>>"; - o << " is:\t" << I->second << "\n"; - } -} - //===----------------------------------------------------------------------===// // DominatorTree Implementation //===----------------------------------------------------------------------===// @@ -528,6 +421,20 @@ DominanceFrontier::calculate(const DominatorTree &DT, return *Result; } +namespace llvm { +static std::ostream &operator<<(std::ostream &o, + const std::set<BasicBlock*> &BBs) { + for (std::set<BasicBlock*>::const_iterator I = BBs.begin(), E = BBs.end(); + I != E; ++I) + if (*I) + WriteAsOperand(o, *I, false); + else + o << " <<exit node>>"; + return o; +} +} + + void DominanceFrontierBase::print(std::ostream &o, const Module* ) const { for (const_iterator I = begin(), E = end(); I != E; ++I) { o << " DomFrontier for BB"; @@ -1071,5 +978,3 @@ void ETForestBase::print(std::ostream &o, const Module *) const { } o << "\n"; } - -DEFINING_FILE_FOR(DominatorSet) |