diff --git a/lib/Analysis/IntervalPartition.cpp b/lib/Analysis/IntervalPartition.cpp new file mode 100644 index 00000000000..84104777841 --- /dev/null +++ b/lib/Analysis/IntervalPartition.cpp @@ -0,0 +1,181 @@ +//===- IntervalPartition.cpp - Interval Partition module code ----*- C++ -*--=// +// +// This file contains the definition of the cfg::IntervalPartition class, which +// calculates and represent the interval partition of a method. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Analysis/IntervalIterator.h" + +using namespace cfg; + +//===----------------------------------------------------------------------===// +// IntervalPartition Implementation +//===----------------------------------------------------------------------===// + +template static inline void deleter(T *Ptr) { delete Ptr; } + +// Destructor - Free memory +IntervalPartition::~IntervalPartition() { + for_each(begin(), end(), deleter); +} + +// addNodeToInterval - This method exists to assist the generic ProcessNode +// with the task of adding a node to the new interval, depending on the +// type of the source node. In the case of a CFG source graph (BasicBlock +// case), the BasicBlock itself is added to the interval. +// +inline void IntervalPartition::addNodeToInterval(Interval *Int, BasicBlock *BB){ + Int->Nodes.push_back(BB); + IntervalMap.insert(make_pair(BB, Int)); +} + +// addNodeToInterval - This method exists to assist the generic ProcessNode +// with the task of adding a node to the new interval, depending on the +// type of the source node. In the case of a CFG source graph (BasicBlock +// case), the BasicBlock itself is added to the interval. In the case of +// an IntervalPartition source graph (Interval case), all of the member +// BasicBlocks are added to the interval. +// +inline void IntervalPartition::addNodeToInterval(Interval *Int, Interval *I) { + // Add all of the nodes in I as new nodes in Int. + copy(I->Nodes.begin(), I->Nodes.end(), back_inserter(Int->Nodes)); + + // Add mappings for all of the basic blocks in I to the IntervalPartition + for (Interval::node_iterator It = I->Nodes.begin(), End = I->Nodes.end(); + It != End; ++It) + IntervalMap.insert(make_pair(*It, Int)); +} + + +// ProcessNode - This method is called by ProcessInterval to add nodes to the +// interval being constructed, and it is also called recursively as it walks +// the source graph. A node is added to the current interval only if all of +// its predecessors are already in the graph. This also takes care of keeping +// the successor set of an interval up to date. +// +// This method is templated because it may operate on two different source +// graphs: a basic block graph, or a preexisting interval graph. +// +template +void IntervalPartition::ProcessNode(Interval *Int, + NodeTy *Node, OrigContainer *OC) { + assert(Int && "Null interval == bad!"); + assert(Node && "Null Node == bad!"); + + BasicBlock *NodeHeader = getNodeHeader(Node); + Interval *CurInt = getBlockInterval(NodeHeader); + if (CurInt == Int) { // Already in this interval... + return; + } else if (CurInt != 0) { // In another interval, add as successor + if (!Int->isSuccessor(NodeHeader)) // Add only if not already in set + Int->Successors.push_back(NodeHeader); + } else { // Otherwise, not in interval yet + for (typename NodeTy::pred_iterator I = pred_begin(Node), + E = pred_end(Node); I != E; ++I) { + if (!Int->contains(*I)) { // If pred not in interval, we can't be + if (!Int->isSuccessor(NodeHeader)) // Add only if not already in set + Int->Successors.push_back(NodeHeader); + return; // See you later + } + } + + // If we get here, then all of the predecessors of BB are in the interval + // already. In this case, we must add BB to the interval! + addNodeToInterval(Int, Node); + + if (Int->isSuccessor(NodeHeader)) { + // If we were in the successor list from before... remove from succ list + Int->Successors.erase(remove(Int->Successors.begin(), + Int->Successors.end(), NodeHeader), + Int->Successors.end()); + } + + // Now that we have discovered that Node is in the interval, perhaps some of + // its successors are as well? + for (typename NodeTy::succ_iterator It = succ_begin(Node), + End = succ_end(Node); It != End; ++It) + ProcessNode(Int, getSourceGraphNode(OC, *It), OC); + } +} + + +// ProcessInterval - This method is used during the construction of the +// interval graph. It walks through the source graph, recursively creating +// an interval per invokation until the entire graph is covered. This uses +// the ProcessNode method to add all of the nodes to the interval. +// +// This method is templated because it may operate on two different source +// graphs: a basic block graph, or a preexisting interval graph. +// +template +void IntervalPartition::ProcessInterval(NodeTy *Node, OrigContainer *OC) { + BasicBlock *Header = getNodeHeader(Node); + if (getBlockInterval(Header)) return; // Interval already constructed? + + // Create a new interval and add the interval to our current set + Interval *Int = new Interval(Header); + IntervalList.push_back(Int); + IntervalMap.insert(make_pair(Header, Int)); + + // Check all of our successors to see if they are in the interval... + for (typename NodeTy::succ_iterator I = succ_begin(Node), E = succ_end(Node); + I != E; ++I) + ProcessNode(Int, getSourceGraphNode(OC, *I), OC); + + // Build all of the successor intervals of this interval now... + for(Interval::succ_iterator I = Int->Successors.begin(), + E = Int->Successors.end(); I != E; ++I) { + ProcessInterval(getSourceGraphNode(OC, *I), OC); + } +} + + + +// updatePredecessors - Interval generation only sets the successor fields of +// the interval data structures. After interval generation is complete, +// run through all of the intervals and propogate successor info as +// predecessor info. +// +void IntervalPartition::updatePredecessors(cfg::Interval *Int) { + BasicBlock *Header = Int->getHeaderNode(); + for (Interval::succ_iterator I = Int->Successors.begin(), + E = Int->Successors.end(); I != E; ++I) + getBlockInterval(*I)->Predecessors.push_back(Header); +} + + + +// IntervalPartition ctor - Build the first level interval partition for the +// specified method... +// +IntervalPartition::IntervalPartition(Method *M) { + BasicBlock *MethodStart = M->getBasicBlocks().front(); + assert(MethodStart && "Cannot operate on prototypes!"); + + ProcessInterval(MethodStart, M); + RootInterval = getBlockInterval(MethodStart); + + // Now that we know all of the successor information, propogate this to the + // predecessors for each block... + for(iterator I = begin(), E = end(); I != E; ++I) + updatePredecessors(*I); +} + + +// IntervalPartition ctor - Build a reduced interval partition from an +// existing interval graph. This takes an additional boolean parameter to +// distinguish it from a copy constructor. Always pass in false for now. +// +IntervalPartition::IntervalPartition(IntervalPartition &I, bool) { + Interval *MethodStart = I.getRootInterval(); + assert(MethodStart && "Cannot operate on empty IntervalPartitions!"); + + ProcessInterval(MethodStart, &I); + RootInterval = getBlockInterval(*MethodStart->Nodes.begin()); + + // Now that we know all of the successor information, propogate this to the + // predecessors for each block... + for(iterator I = begin(), E = end(); I != E; ++I) + updatePredecessors(*I); +}