-//===- IntervalIterator.h - Interval Iterator Declaration --------*- C++ -*--=//
+//===- IntervalIterator.h - Interval Iterator Declaration -------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file defines an iterator that enumerates the intervals in a control flow
// graph of some sort. This iterator is parametric, allowing iterator over the
// following types of graphs:
-//
-// TODO
+//
+// 1. A Function* object, composed of BasicBlock nodes.
+// 2. An IntervalPartition& object, composed of Interval nodes.
+//
+// This iterator is defined to walk the control flow graph, returning intervals
+// in depth first order. These intervals are completely filled in except for
+// the predecessor fields (the successor information is filled in however).
+//
+// By default, the intervals created by this iterator are deleted after they
+// are no longer any use to the iterator. This behavior can be changed by
+// passing a false value into the intervals_begin() function. This causes the
+// IOwnMem member to be set, and the intervals to not be deleted.
+//
+// It is only safe to use this if all of the intervals are deleted by the caller
+// and all of the intervals are processed. However, the user of the iterator is
+// not allowed to modify or delete the intervals until after the iterator has
+// been used completely. The IntervalPartition class uses this functionality.
//
//===----------------------------------------------------------------------===//
-#ifndef LLVM_INTERVAL_ITERATOR_H
-#define LLVM_INTERVAL_ITERATOR_H
+#ifndef LLVM_ANALYSIS_INTERVALITERATOR_H
+#define LLVM_ANALYSIS_INTERVALITERATOR_H
#include "llvm/Analysis/IntervalPartition.h"
-#include "llvm/Method.h"
-#include "llvm/CFG.h"
-#include <stack>
-#include <set>
+#include "llvm/IR/Function.h"
+#include "llvm/Support/CFG.h"
#include <algorithm>
+#include <set>
+#include <vector>
-namespace cfg {
-
-// TODO: Provide an interval iterator that codifies the internals of
-// IntervalPartition. Inside, it would have a stack of Interval*'s, and would
-// walk the interval partition in depth first order. IntervalPartition would
-// then be a client of this iterator. The iterator should work on Method*,
-// const Method*, IntervalPartition*, and const IntervalPartition*.
-//
-
+namespace llvm {
-// getNodeHeader - Given a source graph node and the source graph, return the
+// getNodeHeader - Given a source graph node and the source graph, return the
// BasicBlock that is the header node. This is the opposite of
// getSourceGraphNode.
//
inline BasicBlock *getNodeHeader(BasicBlock *BB) { return BB; }
inline BasicBlock *getNodeHeader(Interval *I) { return I->getHeaderNode(); }
-// getSourceGraphNode - Given a BasicBlock and the source graph, return the
+// getSourceGraphNode - Given a BasicBlock and the source graph, return the
// source graph node that corresponds to the BasicBlock. This is the opposite
// of getNodeHeader.
//
-inline BasicBlock *getSourceGraphNode(Method *, BasicBlock *BB) {
- return BB;
+inline BasicBlock *getSourceGraphNode(Function *, BasicBlock *BB) {
+ return BB;
}
-inline Interval *getSourceGraphNode(IntervalPartition *IP, BasicBlock *BB) {
+inline Interval *getSourceGraphNode(IntervalPartition *IP, BasicBlock *BB) {
return IP->getBlockInterval(BB);
}
// 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
+// 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 addNodeToInterval(Interval *Int, BasicBlock *BB){
+inline void addNodeToInterval(Interval *Int, BasicBlock *BB) {
Int->Nodes.push_back(BB);
}
// 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
+// 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.
}
-template<class NodeTy, class OrigContainer_t>
+
+
+
+template<class NodeTy, class OrigContainer_t, class GT = GraphTraits<NodeTy*>,
+ class IGT = GraphTraits<Inverse<NodeTy*> > >
class IntervalIterator {
- stack<pair<Interval, typename Interval::succ_iterator> > IntStack;
- set<BasicBlock*> Visited;
+ std::vector<std::pair<Interval*, typename Interval::succ_iterator> > IntStack;
+ std::set<BasicBlock*> Visited;
OrigContainer_t *OrigContainer;
+ bool IOwnMem; // If True, delete intervals when done with them
+ // See file header for conditions of use
public:
- typedef BasicBlock* _BB;
-
typedef IntervalIterator<NodeTy, OrigContainer_t> _Self;
- typedef forward_iterator_tag iterator_category;
-
+ typedef std::forward_iterator_tag iterator_category;
+
IntervalIterator() {} // End iterator, empty stack
- IntervalIterator(Method *M) {
+ IntervalIterator(Function *M, bool OwnMemory) : IOwnMem(OwnMemory) {
OrigContainer = M;
- if (!ProcessInterval(M->getBasicBlocks().front())) {
- assert(0 && "ProcessInterval should never fail for first interval!");
+ if (!ProcessInterval(&M->front())) {
+ llvm_unreachable("ProcessInterval should never fail for first interval!");
}
}
- IntervalIterator(IntervalPartition &IP) {
+ IntervalIterator(IntervalPartition &IP, bool OwnMemory) : IOwnMem(OwnMemory) {
OrigContainer = &IP;
if (!ProcessInterval(IP.getRootInterval())) {
- assert(0 && "ProcessInterval should never fail for first interval!");
+ llvm_unreachable("ProcessInterval should never fail for first interval!");
}
}
- inline bool operator==(const _Self& x) const { return IntStack == x.IntStack; }
+ inline ~IntervalIterator() {
+ if (IOwnMem)
+ while (!IntStack.empty()) {
+ delete operator*();
+ IntStack.pop_back();
+ }
+ }
+
+ inline bool operator==(const _Self& x) const { return IntStack == x.IntStack;}
inline bool operator!=(const _Self& x) const { return !operator==(x); }
- inline Interval &operator*() const { return IntStack.top(); }
- inline Interval *operator->() const { return &(operator*()); }
+ inline const Interval *operator*() const { return IntStack.back().first; }
+ inline Interval *operator*() { return IntStack.back().first; }
+ inline const Interval *operator->() const { return operator*(); }
+ inline Interval *operator->() { return operator*(); }
- inline _Self& operator++() { // Preincrement
+ _Self& operator++() { // Preincrement
+ assert(!IntStack.empty() && "Attempting to use interval iterator at end!");
do {
- // All of the intervals on the stack have been visited. Try visiting their
- // successors now.
- Interval &CurInt = IntStack.top().first;
- Interval::iterator &SuccIt = IntStack.top().second,End = succ_end(&CurInt);
+ // All of the intervals on the stack have been visited. Try visiting
+ // their successors now.
+ Interval::succ_iterator &SuccIt = IntStack.back().second,
+ EndIt = succ_end(IntStack.back().first);
+ while (SuccIt != EndIt) { // Loop over all interval succs
+ bool Done = ProcessInterval(getSourceGraphNode(OrigContainer, *SuccIt));
+ ++SuccIt; // Increment iterator
+ if (Done) return *this; // Found a new interval! Use it!
+ }
- for (; SuccIt != End; ++SuccIt) // Loop over all interval successors
- if (ProcessInterval(*SuccIt)) // Found a new interval!
- return *this; // Use it!
+ // Free interval memory... if necessary
+ if (IOwnMem) delete IntStack.back().first;
// We ran out of successors for this interval... pop off the stack
- IntStack.pop();
+ IntStack.pop_back();
} while (!IntStack.empty());
- return *this;
+ return *this;
}
inline _Self operator++(int) { // Postincrement
- _Self tmp = *this; ++*this; return tmp;
+ _Self tmp = *this; ++*this; return tmp;
}
private:
- // ProcessInterval - This method is used during the construction of the
+ // 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
+ // an interval per invocation 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
BasicBlock *Header = getNodeHeader(Node);
if (Visited.count(Header)) return false;
- Interval Int(Header);
+ Interval *Int = new Interval(Header);
Visited.insert(Header); // The header has now been visited!
// 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(OrigContainer, *I));
+ for (typename GT::ChildIteratorType I = GT::child_begin(Node),
+ E = GT::child_end(Node); I != E; ++I)
+ ProcessNode(Int, getSourceGraphNode(OrigContainer, *I));
- IntStack.push(make_pair(Int, succ_begin(&Int)));
+ IntStack.push_back(std::make_pair(Int, succ_begin(Int)));
return true;
}
-
+
// 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
void ProcessNode(Interval *Int, NodeTy *Node) {
assert(Int && "Null interval == bad!");
assert(Node && "Null Node == bad!");
-
+
BasicBlock *NodeHeader = getNodeHeader(Node);
if (Visited.count(NodeHeader)) { // Node already been visited?
if (Int->contains(NodeHeader)) { // Already in this interval...
- return;
- } else { // In another interval, add as successor
- if (!Int->isSuccessor(NodeHeader)) // Add only if not already in set
- Int->Successors.push_back(NodeHeader);
+ return;
+ } else { // In other 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
- }
+ for (typename IGT::ChildIteratorType I = IGT::child_begin(Node),
+ E = IGT::child_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);
Visited.insert(NodeHeader); // The node has now been visited!
-
+
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());
+ // If we were in the successor list from before... remove from succ list
+ Int->Successors.erase(std::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(OrigContainer, *It));
+ for (typename GT::ChildIteratorType It = GT::child_begin(Node),
+ End = GT::child_end(Node); It != End; ++It)
+ ProcessNode(Int, getSourceGraphNode(OrigContainer, *It));
}
}
};
-typedef IntervalIterator<BasicBlock, Method> method_interval_iterator;
-typedef IntervalIterator<Interval, IntervalPartition> interval_part_interval_iterator;
+typedef IntervalIterator<BasicBlock, Function> function_interval_iterator;
+typedef IntervalIterator<Interval, IntervalPartition>
+ interval_part_interval_iterator;
-inline method_interval_iterator intervals_begin(Method *M) {
- return method_interval_iterator(M);
+inline function_interval_iterator intervals_begin(Function *F,
+ bool DeleteInts = true) {
+ return function_interval_iterator(F, DeleteInts);
}
-inline method_interval_iterator intervals_end(Method *M) {
- return method_interval_iterator();
+inline function_interval_iterator intervals_end(Function *) {
+ return function_interval_iterator();
}
-inline interval_part_interval_iterator intervals_begin(IntervalPartition &IP) {
- return interval_part_interval_iterator(IP);
+inline interval_part_interval_iterator
+ intervals_begin(IntervalPartition &IP, bool DeleteIntervals = true) {
+ return interval_part_interval_iterator(IP, DeleteIntervals);
}
inline interval_part_interval_iterator intervals_end(IntervalPartition &IP) {
return interval_part_interval_iterator();
}
-} // End namespace cfg
+} // End llvm namespace
#endif