#include "llvm/Analysis/Dominators.h"
#include "llvm/Support/CFG.h"
-#include "llvm/Assembly/Writer.h"
+#include "llvm/Support/Compiler.h"
#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/SetOperations.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/DominatorInternals.h"
#include "llvm/Instructions.h"
#include "llvm/Support/Streams.h"
-#include "DominatorCalculation.h"
#include <algorithm>
using namespace llvm;
//
//===----------------------------------------------------------------------===//
+TEMPLATE_INSTANTIATION(class DomTreeNodeBase<BasicBlock>);
+TEMPLATE_INSTANTIATION(class DominatorTreeBase<BasicBlock>);
+
char DominatorTree::ID = 0;
static RegisterPass<DominatorTree>
E("domtree", "Dominator Tree Construction", true);
-// NewBB is split and now it has one successor. Update dominator tree to
-// reflect this change.
-void DominatorTree::splitBlock(BasicBlock *NewBB) {
- assert(NewBB->getTerminator()->getNumSuccessors() == 1
- && "NewBB should have a single successor!");
- BasicBlock *NewBBSucc = NewBB->getTerminator()->getSuccessor(0);
-
- std::vector<BasicBlock*> PredBlocks;
- for (pred_iterator PI = pred_begin(NewBB), PE = pred_end(NewBB);
- PI != PE; ++PI)
- PredBlocks.push_back(*PI);
-
- assert(!PredBlocks.empty() && "No predblocks??");
-
- // The newly inserted basic block will dominate existing basic blocks iff the
- // PredBlocks dominate all of the non-pred blocks. If all predblocks dominate
- // the non-pred blocks, then they all must be the same block!
- //
- bool NewBBDominatesNewBBSucc = true;
- {
- BasicBlock *OnePred = PredBlocks[0];
- unsigned i = 1, e = PredBlocks.size();
- for (i = 1; !isReachableFromEntry(OnePred); ++i) {
- assert(i != e && "Didn't find reachable pred?");
- OnePred = PredBlocks[i];
- }
-
- for (; i != e; ++i)
- if (PredBlocks[i] != OnePred && isReachableFromEntry(OnePred)) {
- NewBBDominatesNewBBSucc = false;
- break;
- }
-
- if (NewBBDominatesNewBBSucc)
- for (pred_iterator PI = pred_begin(NewBBSucc), E = pred_end(NewBBSucc);
- PI != E; ++PI)
- if (*PI != NewBB && !dominates(NewBBSucc, *PI)) {
- NewBBDominatesNewBBSucc = false;
- break;
- }
- }
-
- // The other scenario where the new block can dominate its successors are when
- // all predecessors of NewBBSucc that are not NewBB are dominated by NewBBSucc
- // already.
- if (!NewBBDominatesNewBBSucc) {
- NewBBDominatesNewBBSucc = true;
- for (pred_iterator PI = pred_begin(NewBBSucc), E = pred_end(NewBBSucc);
- PI != E; ++PI)
- if (*PI != NewBB && !dominates(NewBBSucc, *PI)) {
- NewBBDominatesNewBBSucc = false;
- break;
- }
- }
-
- // Find NewBB's immediate dominator and create new dominator tree node for
- // NewBB.
- BasicBlock *NewBBIDom = 0;
- unsigned i = 0;
- for (i = 0; i < PredBlocks.size(); ++i)
- if (isReachableFromEntry(PredBlocks[i])) {
- NewBBIDom = PredBlocks[i];
- break;
- }
- assert(i != PredBlocks.size() && "No reachable preds?");
- for (i = i + 1; i < PredBlocks.size(); ++i) {
- if (isReachableFromEntry(PredBlocks[i]))
- NewBBIDom = findNearestCommonDominator(NewBBIDom, PredBlocks[i]);
- }
- assert(NewBBIDom && "No immediate dominator found??");
-
- // Create the new dominator tree node... and set the idom of NewBB.
- DomTreeNode *NewBBNode = addNewBlock(NewBB, NewBBIDom);
-
- // If NewBB strictly dominates other blocks, then it is now the immediate
- // dominator of NewBBSucc. Update the dominator tree as appropriate.
- if (NewBBDominatesNewBBSucc) {
- DomTreeNode *NewBBSuccNode = getNode(NewBBSucc);
- changeImmediateDominator(NewBBSuccNode, NewBBNode);
- }
-}
-
-void DominatorTreeBase::updateDFSNumbers() {
- unsigned DFSNum = 0;
-
- SmallVector<std::pair<DomTreeNode*, DomTreeNode::iterator>, 32> WorkStack;
-
- for (unsigned i = 0, e = Roots.size(); i != e; ++i) {
- DomTreeNode *ThisRoot = getNode(Roots[i]);
- WorkStack.push_back(std::make_pair(ThisRoot, ThisRoot->begin()));
- ThisRoot->DFSNumIn = DFSNum++;
-
- while (!WorkStack.empty()) {
- DomTreeNode *Node = WorkStack.back().first;
- DomTreeNode::iterator ChildIt = WorkStack.back().second;
-
- // If we visited all of the children of this node, "recurse" back up the
- // stack setting the DFOutNum.
- if (ChildIt == Node->end()) {
- Node->DFSNumOut = DFSNum++;
- WorkStack.pop_back();
- } else {
- // Otherwise, recursively visit this child.
- DomTreeNode *Child = *ChildIt;
- ++WorkStack.back().second;
-
- WorkStack.push_back(std::make_pair(Child, Child->begin()));
- Child->DFSNumIn = DFSNum++;
- }
- }
- }
-
- SlowQueries = 0;
- DFSInfoValid = true;
-}
-
-/// isReachableFromEntry - Return true if A is dominated by the entry
-/// block of the function containing it.
-const bool DominatorTreeBase::isReachableFromEntry(BasicBlock* A) {
- assert (!isPostDominator()
- && "This is not implemented for post dominators");
- return dominates(&A->getParent()->getEntryBlock(), A);
-}
-
-// dominates - Return true if A dominates B. THis performs the
-// special checks necessary if A and B are in the same basic block.
-bool DominatorTreeBase::dominates(Instruction *A, Instruction *B) {
- 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;
- }
-}
-
-// DominatorTreeBase::reset - Free all of the tree node memory.
-//
-void DominatorTreeBase::reset() {
- for (DomTreeNodeMapType::iterator I = DomTreeNodes.begin(),
- E = DomTreeNodes.end(); I != E; ++I)
- delete I->second;
- DomTreeNodes.clear();
- IDoms.clear();
- Roots.clear();
- Vertex.clear();
- RootNode = 0;
-}
-
-DomTreeNode *DominatorTreeBase::getNodeForBlock(BasicBlock *BB) {
- if (DomTreeNode *BBNode = DomTreeNodes[BB])
- return BBNode;
-
- // Haven't calculated this node yet? Get or calculate the node for the
- // immediate dominator.
- BasicBlock *IDom = getIDom(BB);
- DomTreeNode *IDomNode = getNodeForBlock(IDom);
-
- // Add a new tree node for this BasicBlock, and link it as a child of
- // IDomNode
- DomTreeNode *C = new DomTreeNode(BB, IDomNode);
- return DomTreeNodes[BB] = IDomNode->addChild(C);
-}
-
-/// findNearestCommonDominator - Find nearest common dominator basic block
-/// for basic block A and B. If there is no such block then return NULL.
-BasicBlock *DominatorTreeBase::findNearestCommonDominator(BasicBlock *A,
- BasicBlock *B) {
-
- assert (!isPostDominator()
- && "This is not implemented for post dominators");
- assert (A->getParent() == B->getParent()
- && "Two blocks are not in same function");
-
- // If either A or B is a entry block then it is nearest common dominator.
- BasicBlock &Entry = A->getParent()->getEntryBlock();
- if (A == &Entry || B == &Entry)
- return &Entry;
-
- // If B dominates A then B is nearest common dominator.
- if (dominates(B, A))
- return B;
-
- // If A dominates B then A is nearest common dominator.
- if (dominates(A, B))
- return A;
-
- DomTreeNode *NodeA = getNode(A);
- DomTreeNode *NodeB = getNode(B);
-
- // Collect NodeA dominators set.
- SmallPtrSet<DomTreeNode*, 16> NodeADoms;
- NodeADoms.insert(NodeA);
- DomTreeNode *IDomA = NodeA->getIDom();
- while (IDomA) {
- NodeADoms.insert(IDomA);
- IDomA = IDomA->getIDom();
- }
-
- // Walk NodeB immediate dominators chain and find common dominator node.
- DomTreeNode *IDomB = NodeB->getIDom();
- while(IDomB) {
- if (NodeADoms.count(IDomB) != 0)
- return IDomB->getBlock();
-
- IDomB = IDomB->getIDom();
- }
-
- return NULL;
-}
-
-void DomTreeNode::setIDom(DomTreeNode *NewIDom) {
- assert(IDom && "No immediate dominator?");
- if (IDom != NewIDom) {
- std::vector<DomTreeNode*>::iterator I =
- std::find(IDom->Children.begin(), IDom->Children.end(), this);
- assert(I != IDom->Children.end() &&
- "Not in immediate dominator children set!");
- // I am no longer your child...
- IDom->Children.erase(I);
-
- // Switch to new dominator
- IDom = NewIDom;
- IDom->Children.push_back(this);
- }
-}
-
-static std::ostream &operator<<(std::ostream &o, const DomTreeNode *Node) {
- if (Node->getBlock())
- WriteAsOperand(o, Node->getBlock(), false);
- else
- o << " <<exit node>>";
-
- o << " {" << Node->getDFSNumIn() << "," << Node->getDFSNumOut() << "}";
-
- return o << "\n";
-}
-
-static void PrintDomTree(const DomTreeNode *N, std::ostream &o,
- unsigned Lev) {
- o << std::string(2*Lev, ' ') << "[" << Lev << "] " << N;
- for (DomTreeNode::const_iterator I = N->begin(), E = N->end();
- I != E; ++I)
- PrintDomTree(*I, o, Lev+1);
-}
-
-/// eraseNode - Removes a node from the domiantor tree. Block must not
-/// domiante any other blocks. Removes node from its immediate dominator's
-/// children list. Deletes dominator node associated with basic block BB.
-void DominatorTreeBase::eraseNode(BasicBlock *BB) {
- DomTreeNode *Node = getNode(BB);
- assert (Node && "Removing node that isn't in dominator tree.");
- assert (Node->getChildren().empty() && "Node is not a leaf node.");
-
- // Remove node from immediate dominator's children list.
- DomTreeNode *IDom = Node->getIDom();
- if (IDom) {
- std::vector<DomTreeNode*>::iterator I =
- std::find(IDom->Children.begin(), IDom->Children.end(), Node);
- assert(I != IDom->Children.end() &&
- "Not in immediate dominator children set!");
- // I am no longer your child...
- IDom->Children.erase(I);
- }
-
- DomTreeNodes.erase(BB);
- delete Node;
-}
-
-void DominatorTreeBase::print(std::ostream &o, const Module* ) const {
- o << "=============================--------------------------------\n";
- o << "Inorder Dominator Tree: ";
- if (DFSInfoValid)
- o << "DFSNumbers invalid: " << SlowQueries << " slow queries.";
- o << "\n";
-
- PrintDomTree(getRootNode(), o, 1);
-}
-
-void DominatorTreeBase::dump() {
- print(llvm::cerr);
-}
-
bool DominatorTree::runOnFunction(Function &F) {
- reset(); // Reset from the last time we were run...
- Roots.push_back(&F.getEntryBlock());
- DTcalculate(*this, F);
+ DT->recalculate(F);
+
return false;
}
}
if (NewBBI != end()) {
- DominanceFrontier::DomSetType NewBBSet = NewBBI->second;
- NewBBSet.insert(Set.begin(), Set.end());
+ for (DominanceFrontier::DomSetType::iterator SetI = Set.begin(),
+ E = Set.end(); SetI != E; ++SetI) {
+ BasicBlock *SB = *SetI;
+ addToFrontier(NewBBI, SB);
+ }
} else
addBasicBlock(NewBB, Set);
}
projects / oota-llvm.git / blobdiff