mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-31 16:02:52 +01:00
604a50cd71
The RegionInfo pass detects single entry single exit regions in a function, where a region is defined as any subgraph that is connected to the remaining graph at only two spots. Furthermore an hierarchical region tree is built. Use it by calling "opt -regions analyze" or "opt -view-regions". llvm-svn: 109089
343 lines
11 KiB
C++
343 lines
11 KiB
C++
//===- RegionIterator.h - Iterators to iteratate over Regions ---*- 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 the iterators to iterate over the elements of a Region.
|
|
//===----------------------------------------------------------------------===//
|
|
#ifndef LLVM_ANALYSIS_REGION_ITERATOR_H
|
|
#define LLVM_ANALYSIS_REGION_ITERATOR_H
|
|
|
|
#include "llvm/ADT/GraphTraits.h"
|
|
#include "llvm/ADT/SmallPtrSet.h"
|
|
#include "llvm/ADT/PointerIntPair.h"
|
|
#include "llvm/Analysis/RegionInfo.h"
|
|
#include "llvm/Support/CFG.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
|
|
namespace llvm {
|
|
//===----------------------------------------------------------------------===//
|
|
/// @brief Hierachical RegionNode successor iterator.
|
|
///
|
|
/// This iterator iterates over all successors of a RegionNode.
|
|
///
|
|
/// For a BasicBlock RegionNode it skips all BasicBlocks that are not part of
|
|
/// the parent Region. Furthermore for BasicBlocks that start a subregion, a
|
|
/// RegionNode representing the subregion is returned.
|
|
///
|
|
/// For a subregion RegionNode there is just one successor. The RegionNode
|
|
/// representing the exit of the subregion.
|
|
template<class NodeType>
|
|
class RNSuccIterator : public std::iterator<std::forward_iterator_tag,
|
|
NodeType, ptrdiff_t>
|
|
{
|
|
typedef std::iterator<std::forward_iterator_tag, NodeType, ptrdiff_t> super;
|
|
// The iterator works in two modes, bb mode or region mode.
|
|
enum ItMode{
|
|
// In BB mode it returns all successors of this BasicBlock as its
|
|
// successors.
|
|
ItBB,
|
|
// In region mode there is only one successor, thats the regionnode mapping
|
|
// to the exit block of the regionnode
|
|
ItRgBegin, // At the beginning of the regionnode successor.
|
|
ItRgEnd // At the end of the regionnode successor.
|
|
};
|
|
|
|
// Use two bit to represent the mode iterator.
|
|
PointerIntPair<NodeType*, 2, enum ItMode> Node;
|
|
|
|
// The block successor iterator.
|
|
succ_iterator BItor;
|
|
|
|
// advanceRegionSucc - A region node has only one successor. It reaches end
|
|
// once we advance it.
|
|
void advanceRegionSucc() {
|
|
assert(Node.getInt() == ItRgBegin && "Cannot advance region successor!");
|
|
Node.setInt(ItRgEnd);
|
|
}
|
|
|
|
NodeType* getNode() const{ return Node.getPointer(); }
|
|
|
|
// isRegionMode - Is the current iterator in region mode?
|
|
bool isRegionMode() const { return Node.getInt() != ItBB; }
|
|
|
|
// Get the immediate successor. This function may return a Basic Block
|
|
// RegionNode or a subregion RegionNode.
|
|
RegionNode* getISucc(BasicBlock* BB) const {
|
|
RegionNode *succ;
|
|
succ = getNode()->getParent()->getNode(BB);
|
|
assert(succ && "BB not in Region or entered subregion!");
|
|
return succ;
|
|
}
|
|
|
|
// getRegionSucc - Return the successor basic block of a SubRegion RegionNode.
|
|
inline BasicBlock* getRegionSucc() const {
|
|
assert(Node.getInt() == ItRgBegin && "Cannot get the region successor!");
|
|
return getNode()->template getNodeAs<Region>()->getExit();
|
|
}
|
|
|
|
// isExit - Is this the exit BB of the Region?
|
|
inline bool isExit(BasicBlock* BB) const {
|
|
return getNode()->getParent()->getExit() == BB;
|
|
}
|
|
public:
|
|
typedef RNSuccIterator<NodeType> Self;
|
|
|
|
typedef typename super::pointer pointer;
|
|
|
|
/// @brief Create begin iterator of a RegionNode.
|
|
inline RNSuccIterator(NodeType* node)
|
|
: Node(node, node->isSubRegion() ? ItRgBegin : ItBB),
|
|
BItor(succ_begin(node->getEntry())) {
|
|
|
|
|
|
// Skip the exit block
|
|
if (!isRegionMode())
|
|
while (succ_end(node->getEntry()) != BItor && isExit(*BItor))
|
|
++BItor;
|
|
|
|
if (isRegionMode() && isExit(getRegionSucc()))
|
|
advanceRegionSucc();
|
|
}
|
|
|
|
/// @brief Create an end iterator.
|
|
inline RNSuccIterator(NodeType* node, bool)
|
|
: Node(node, node->isSubRegion() ? ItRgEnd : ItBB),
|
|
BItor(succ_end(node->getEntry())) {}
|
|
|
|
inline bool operator==(const Self& x) const {
|
|
assert(isRegionMode() == x.isRegionMode() && "Broken iterator!");
|
|
if (isRegionMode())
|
|
return Node.getInt() == x.Node.getInt();
|
|
else
|
|
return BItor == x.BItor;
|
|
}
|
|
|
|
inline bool operator!=(const Self& x) const { return !operator==(x); }
|
|
|
|
inline pointer operator*() const {
|
|
BasicBlock* BB = isRegionMode() ? getRegionSucc() : *BItor;
|
|
assert(!isExit(BB) && "Iterator out of range!");
|
|
return getISucc(BB);
|
|
}
|
|
|
|
inline Self& operator++() {
|
|
if(isRegionMode()) {
|
|
// The Region only has 1 successor.
|
|
advanceRegionSucc();
|
|
} else {
|
|
// Skip the exit.
|
|
do
|
|
++BItor;
|
|
while (BItor != succ_end(getNode()->getEntry())
|
|
&& isExit(*BItor));
|
|
}
|
|
return *this;
|
|
}
|
|
|
|
inline Self operator++(int) {
|
|
Self tmp = *this;
|
|
++*this;
|
|
return tmp;
|
|
}
|
|
|
|
inline const Self &operator=(const Self &I) {
|
|
if (this != &I) {
|
|
assert(getNode()->getParent() == I.getNode()->getParent()
|
|
&& "Cannot assign iterators of two different regions!");
|
|
Node = I.Node;
|
|
BItor = I.BItor;
|
|
}
|
|
return *this;
|
|
}
|
|
};
|
|
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
/// @brief Flat RegionNode iterator.
|
|
///
|
|
/// The Flat Region iterator will iterate over all BasicBlock RegionNodes that
|
|
/// are contained in the Region and its subregions. This is close to a virtual
|
|
/// control flow graph of the Region.
|
|
template<class NodeType>
|
|
class RNSuccIterator<FlatIt<NodeType> >
|
|
: public std::iterator<std::forward_iterator_tag, NodeType, ptrdiff_t>
|
|
{
|
|
typedef std::iterator<std::forward_iterator_tag, NodeType, ptrdiff_t> super;
|
|
NodeType* Node;
|
|
succ_iterator Itor;
|
|
|
|
public:
|
|
typedef RNSuccIterator<FlatIt<NodeType> > Self;
|
|
typedef typename super::pointer pointer;
|
|
|
|
/// @brief Create the iterator from a RegionNode.
|
|
///
|
|
/// Note that the incoming node must be a bb node, otherwise it will trigger
|
|
/// an assertion when we try to get a BasicBlock.
|
|
inline RNSuccIterator(NodeType* node) : Node(node),
|
|
Itor(succ_begin(node->getEntry())) {
|
|
assert(!Node->isSubRegion()
|
|
&& "Subregion node not allowed in flat iterating mode!");
|
|
assert(Node->getParent() && "A BB node must have a parent!");
|
|
|
|
// Skip the exit block of the iterating region.
|
|
while (succ_end(Node->getEntry()) != Itor
|
|
&& Node->getParent()->getExit() == *Itor)
|
|
++Itor;
|
|
}
|
|
/// @brief Create an end iterator
|
|
inline RNSuccIterator(NodeType* node, bool) : Node(node),
|
|
Itor(succ_end(node->getEntry())) {
|
|
assert(!Node->isSubRegion()
|
|
&& "Subregion node not allowed in flat iterating mode!");
|
|
}
|
|
|
|
inline bool operator==(const Self& x) const {
|
|
assert(Node->getParent() == x.Node->getParent()
|
|
&& "Cannot compare iterators of different regions!");
|
|
|
|
return Itor == x.Itor && Node == x.Node;
|
|
}
|
|
|
|
inline bool operator!=(const Self& x) const { return !operator==(x); }
|
|
|
|
inline pointer operator*() const {
|
|
BasicBlock* BB = *Itor;
|
|
|
|
// Get the iterating region.
|
|
Region* Parent = Node->getParent();
|
|
|
|
// The only case that the successor reaches out of the region is it reaches
|
|
// the exit of the region.
|
|
assert(Parent->getExit() != BB && "iterator out of range!");
|
|
|
|
return Parent->getBBNode(BB);
|
|
}
|
|
|
|
inline Self& operator++() {
|
|
// Skip the exit block of the iterating region.
|
|
do
|
|
++Itor;
|
|
while (Itor != succ_end(Node->getEntry())
|
|
&& Node->getParent()->getExit() == *Itor);
|
|
|
|
return *this;
|
|
}
|
|
|
|
inline Self operator++(int) {
|
|
Self tmp = *this;
|
|
++*this;
|
|
return tmp;
|
|
}
|
|
|
|
inline const Self &operator=(const Self &I) {
|
|
if (this != &I) {
|
|
assert(Node->getParent() == I.Node->getParent()
|
|
&& "Cannot assign iterators to two different regions!");
|
|
Node = I.Node;
|
|
Itor = I.Itor;
|
|
}
|
|
return *this;
|
|
}
|
|
};
|
|
|
|
template<class NodeType>
|
|
inline RNSuccIterator<NodeType> succ_begin(NodeType* Node) {
|
|
return RNSuccIterator<NodeType>(Node);
|
|
}
|
|
|
|
template<class NodeType>
|
|
inline RNSuccIterator<NodeType> succ_end(NodeType* Node) {
|
|
return RNSuccIterator<NodeType>(Node, true);
|
|
}
|
|
|
|
//===--------------------------------------------------------------------===//
|
|
// RegionNode GraphTraits specialization so the bbs in the region can be
|
|
// iterate by generic graph iterators.
|
|
//
|
|
// NodeT can either be region node or const region node, otherwise child_begin
|
|
// and child_end fail.
|
|
|
|
#define RegionNodeGraphTraits(NodeT) \
|
|
template<> struct GraphTraits<NodeT*> { \
|
|
typedef NodeT NodeType; \
|
|
typedef RNSuccIterator<NodeType> ChildIteratorType; \
|
|
static NodeType *getEntryNode(NodeType* N) { return N; } \
|
|
static inline ChildIteratorType child_begin(NodeType *N) { \
|
|
return RNSuccIterator<NodeType>(N); \
|
|
} \
|
|
static inline ChildIteratorType child_end(NodeType *N) { \
|
|
return RNSuccIterator<NodeType>(N, true); \
|
|
} \
|
|
}; \
|
|
template<> struct GraphTraits<FlatIt<NodeT*> > { \
|
|
typedef NodeT NodeType; \
|
|
typedef RNSuccIterator<FlatIt<NodeT> > ChildIteratorType; \
|
|
static NodeType *getEntryNode(NodeType* N) { return N; } \
|
|
static inline ChildIteratorType child_begin(NodeType *N) { \
|
|
return RNSuccIterator<FlatIt<NodeType> >(N); \
|
|
} \
|
|
static inline ChildIteratorType child_end(NodeType *N) { \
|
|
return RNSuccIterator<FlatIt<NodeType> >(N, true); \
|
|
} \
|
|
}
|
|
|
|
#define RegionGraphTraits(RegionT, NodeT) \
|
|
template<> struct GraphTraits<RegionT*> \
|
|
: public GraphTraits<NodeT*> { \
|
|
typedef df_iterator<NodeType*> nodes_iterator; \
|
|
static NodeType *getEntryNode(RegionT* R) { \
|
|
return R->getNode(R->getEntry()); \
|
|
} \
|
|
static nodes_iterator nodes_begin(RegionT* R) { \
|
|
return nodes_iterator::begin(getEntryNode(R)); \
|
|
} \
|
|
static nodes_iterator nodes_end(RegionT* R) { \
|
|
return nodes_iterator::end(getEntryNode(R)); \
|
|
} \
|
|
}; \
|
|
template<> struct GraphTraits<FlatIt<RegionT*> > \
|
|
: public GraphTraits<FlatIt<NodeT*> > { \
|
|
typedef df_iterator<NodeType*, SmallPtrSet<NodeType*, 8>, false, \
|
|
GraphTraits<FlatIt<NodeType*> > > nodes_iterator; \
|
|
static NodeType *getEntryNode(RegionT* R) { \
|
|
return R->getBBNode(R->getEntry()); \
|
|
} \
|
|
static nodes_iterator nodes_begin(RegionT* R) { \
|
|
return nodes_iterator::begin(getEntryNode(R)); \
|
|
} \
|
|
static nodes_iterator nodes_end(RegionT* R) { \
|
|
return nodes_iterator::end(getEntryNode(R)); \
|
|
} \
|
|
}
|
|
|
|
RegionNodeGraphTraits(RegionNode);
|
|
RegionNodeGraphTraits(const RegionNode);
|
|
|
|
RegionGraphTraits(Region, RegionNode);
|
|
RegionGraphTraits(const Region, const RegionNode);
|
|
|
|
template <> struct GraphTraits<RegionInfo*>
|
|
: public GraphTraits<FlatIt<RegionNode*> > {
|
|
typedef df_iterator<NodeType*, SmallPtrSet<NodeType*, 8>, false,
|
|
GraphTraits<FlatIt<NodeType*> > > nodes_iterator;
|
|
|
|
static NodeType *getEntryNode(RegionInfo *RI) {
|
|
return GraphTraits<FlatIt<Region*> >::getEntryNode(RI->getTopLevelRegion());
|
|
}
|
|
static nodes_iterator nodes_begin(RegionInfo* RI) {
|
|
return nodes_iterator::begin(getEntryNode(RI));
|
|
}
|
|
static nodes_iterator nodes_end(RegionInfo *RI) {
|
|
return nodes_iterator::end(getEntryNode(RI));
|
|
}
|
|
};
|
|
|
|
} // End namespace llvm
|
|
|
|
#endif
|