[llvm-commits] [llvm] r44158 - in /llvm/trunk: include/llvm/Analysis/LoopInfo.h lib/Analysis/LoopInfo.cpp
Owen Anderson
resistor at mac.com
Wed Nov 14 21:00:16 PST 2007
Author: resistor
Date: Wed Nov 14 23:00:15 2007
New Revision: 44158
URL: http://llvm.org/viewvc/llvm-project?rev=44158&view=rev
Log:
More templatization.
Modified:
llvm/trunk/include/llvm/Analysis/LoopInfo.h
llvm/trunk/lib/Analysis/LoopInfo.cpp
Modified: llvm/trunk/include/llvm/Analysis/LoopInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/LoopInfo.h?rev=44158&r1=44157&r2=44158&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/LoopInfo.h (original)
+++ llvm/trunk/include/llvm/Analysis/LoopInfo.h Wed Nov 14 23:00:15 2007
@@ -33,9 +33,11 @@
#include "llvm/Pass.h"
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
+#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/GraphTraits.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/Dominators.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/Streams.h"
#include <algorithm>
@@ -54,6 +56,7 @@
class LoopInfo;
class PHINode;
class Instruction;
+template<class N> class LoopInfoBase;
//===----------------------------------------------------------------------===//
/// LoopBase class - Instances of this class are used to represent loops that are
@@ -513,7 +516,7 @@
}
private:
- friend class LoopInfo;
+ friend class LoopInfoBase<BlockT>;
LoopBase(BlockT *BB) : ParentLoop(0) {
Blocks.push_back(BB);
}
@@ -526,61 +529,352 @@
/// LoopInfo - This class builds and contains all of the top level loop
/// structures in the specified function.
///
-class LoopInfo : public FunctionPass {
+
+template<class BlockT>
+class LoopInfoBase {
// BBMap - Mapping of basic blocks to the inner most loop they occur in
- std::map<BasicBlock*, Loop*> BBMap;
- std::vector<Loop*> TopLevelLoops;
- friend class LoopBase<BasicBlock>;
+ std::map<BlockT*, Loop*> BBMap;
+ std::vector<LoopBase<BlockT>*> TopLevelLoops;
+ friend class LoopBase<BlockT>;
+
public:
- static char ID; // Pass identification, replacement for typeid
-
- LoopInfo() : FunctionPass(intptr_t(&ID)) {}
- ~LoopInfo() { releaseMemory(); }
+ LoopInfoBase() { }
+ ~LoopInfoBase() { releaseMemory(); }
+
+ void releaseMemory() {
+ for (typename std::vector<LoopBase<BlockT>* >::iterator I =
+ TopLevelLoops.begin(), E = TopLevelLoops.end(); I != E; ++I)
+ delete *I; // Delete all of the loops...
+ BBMap.clear(); // Reset internal state of analysis
+ TopLevelLoops.clear();
+ }
+
/// iterator/begin/end - The interface to the top-level loops in the current
/// function.
///
- typedef std::vector<Loop*>::const_iterator iterator;
+ typedef typename std::vector<LoopBase<BlockT>*>::const_iterator iterator;
iterator begin() const { return TopLevelLoops.begin(); }
iterator end() const { return TopLevelLoops.end(); }
-
+
/// getLoopFor - Return the inner most loop that BB lives in. If a basic
/// block is in no loop (for example the entry node), null is returned.
///
- Loop *getLoopFor(const BasicBlock *BB) const {
- std::map<BasicBlock *, Loop*>::const_iterator I=
+ LoopBase<BlockT> *getLoopFor(const BlockT *BB) const {
+ typename std::map<BlockT *, LoopBase<BlockT>*>::const_iterator I=
BBMap.find(const_cast<BasicBlock*>(BB));
return I != BBMap.end() ? I->second : 0;
}
-
+
/// operator[] - same as getLoopFor...
///
- const Loop *operator[](const BasicBlock *BB) const {
+ const LoopBase<BlockT> *operator[](const BlockT *BB) const {
return getLoopFor(BB);
}
-
+
/// getLoopDepth - Return the loop nesting level of the specified block...
///
- unsigned getLoopDepth(const BasicBlock *BB) const {
+ unsigned getLoopDepth(const BlockT *BB) const {
const Loop *L = getLoopFor(BB);
return L ? L->getLoopDepth() : 0;
}
// isLoopHeader - True if the block is a loop header node
- bool isLoopHeader(BasicBlock *BB) const {
+ bool isLoopHeader(BlockT *BB) const {
const Loop *L = getLoopFor(BB);
return L && L->getHeader() == BB;
}
+
+ /// removeLoop - This removes the specified top-level loop from this loop info
+ /// object. The loop is not deleted, as it will presumably be inserted into
+ /// another loop.
+ LoopBase<BlockT> *removeLoop(iterator I) {
+ assert(I != end() && "Cannot remove end iterator!");
+ LoopBase<BlockT> *L = *I;
+ assert(L->getParentLoop() == 0 && "Not a top-level loop!");
+ TopLevelLoops.erase(TopLevelLoops.begin() + (I-begin()));
+ return L;
+ }
+
+ /// changeLoopFor - Change the top-level loop that contains BB to the
+ /// specified loop. This should be used by transformations that restructure
+ /// the loop hierarchy tree.
+ void changeLoopFor(BlockT *BB, LoopBase<BlockT> *L) {
+ LoopBase<BlockT> *&OldLoop = BBMap[BB];
+ assert(OldLoop && "Block not in a loop yet!");
+ OldLoop = L;
+ }
+
+ /// changeTopLevelLoop - Replace the specified loop in the top-level loops
+ /// list with the indicated loop.
+ void changeTopLevelLoop(LoopBase<BlockT> *OldLoop,
+ LoopBase<BlockT> *NewLoop) {
+ typename std::vector<LoopBase<BlockT>*>::iterator I =
+ std::find(TopLevelLoops.begin(), TopLevelLoops.end(), OldLoop);
+ assert(I != TopLevelLoops.end() && "Old loop not at top level!");
+ *I = NewLoop;
+ assert(NewLoop->ParentLoop == 0 && OldLoop->ParentLoop == 0 &&
+ "Loops already embedded into a subloop!");
+ }
+
+ /// addTopLevelLoop - This adds the specified loop to the collection of
+ /// top-level loops.
+ void addTopLevelLoop(LoopBase<BlockT> *New) {
+ assert(New->getParentLoop() == 0 && "Loop already in subloop!");
+ TopLevelLoops.push_back(New);
+ }
+
+ /// removeBlock - This method completely removes BB from all data structures,
+ /// including all of the Loop objects it is nested in and our mapping from
+ /// BasicBlocks to loops.
+ void removeBlock(BlockT *BB) {
+ typename std::map<BlockT *, LoopBase<BlockT>*>::iterator I = BBMap.find(BB);
+ if (I != BBMap.end()) {
+ for (Loop *L = I->second; L; L = L->getParentLoop())
+ L->removeBlockFromLoop(BB);
+
+ BBMap.erase(I);
+ }
+ }
+
+ // Internals
+
+ static bool isNotAlreadyContainedIn(Loop *SubLoop, Loop *ParentLoop) {
+ if (SubLoop == 0) return true;
+ if (SubLoop == ParentLoop) return false;
+ return isNotAlreadyContainedIn(SubLoop->getParentLoop(), ParentLoop);
+ }
+
+ void Calculate(DominatorTree &DT) {
+ BlockT *RootNode = DT.getRootNode()->getBlock();
+
+ for (df_iterator<BlockT*> NI = df_begin(RootNode),
+ NE = df_end(RootNode); NI != NE; ++NI)
+ if (LoopBase<BlockT> *L = ConsiderForLoop(*NI, DT))
+ TopLevelLoops.push_back(L);
+ }
+
+ LoopBase<BlockT> *ConsiderForLoop(BlockT *BB, DominatorTree &DT) {
+ if (BBMap.find(BB) != BBMap.end()) return 0;// Haven't processed this node?
+
+ std::vector<BlockT *> TodoStack;
+
+ // Scan the predecessors of BB, checking to see if BB dominates any of
+ // them. This identifies backedges which target this node...
+ for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I)
+ if (DT.dominates(BB, *I)) // If BB dominates it's predecessor...
+ TodoStack.push_back(*I);
+
+ if (TodoStack.empty()) return 0; // No backedges to this block...
+
+ // Create a new loop to represent this basic block...
+ LoopBase<BlockT> *L = new LoopBase<BlockT>(BB);
+ BBMap[BB] = L;
+
+ BlockT *EntryBlock = &BB->getParent()->getEntryBlock();
+
+ while (!TodoStack.empty()) { // Process all the nodes in the loop
+ BlockT *X = TodoStack.back();
+ TodoStack.pop_back();
+
+ if (!L->contains(X) && // As of yet unprocessed??
+ DT.dominates(EntryBlock, X)) { // X is reachable from entry block?
+ // Check to see if this block already belongs to a loop. If this occurs
+ // then we have a case where a loop that is supposed to be a child of the
+ // current loop was processed before the current loop. When this occurs,
+ // this child loop gets added to a part of the current loop, making it a
+ // sibling to the current loop. We have to reparent this loop.
+ if (LoopBase<BlockT> *SubLoop =
+ const_cast<LoopBase<BlockT>*>(getLoopFor(X)))
+ if (SubLoop->getHeader() == X && isNotAlreadyContainedIn(SubLoop, L)) {
+ // Remove the subloop from it's current parent...
+ assert(SubLoop->ParentLoop && SubLoop->ParentLoop != L);
+ LoopBase<BlockT> *SLP = SubLoop->ParentLoop; // SubLoopParent
+ typename std::vector<LoopBase<BlockT>*>::iterator I =
+ std::find(SLP->SubLoops.begin(), SLP->SubLoops.end(), SubLoop);
+ assert(I != SLP->SubLoops.end() && "SubLoop not a child of parent?");
+ SLP->SubLoops.erase(I); // Remove from parent...
+
+ // Add the subloop to THIS loop...
+ SubLoop->ParentLoop = L;
+ L->SubLoops.push_back(SubLoop);
+ }
+
+ // Normal case, add the block to our loop...
+ L->Blocks.push_back(X);
+
+ // Add all of the predecessors of X to the end of the work stack...
+ TodoStack.insert(TodoStack.end(), pred_begin(X), pred_end(X));
+ }
+ }
+
+ // If there are any loops nested within this loop, create them now!
+ for (typename std::vector<BlockT*>::iterator I = L->Blocks.begin(),
+ E = L->Blocks.end(); I != E; ++I)
+ if (LoopBase<BlockT> *NewLoop = ConsiderForLoop(*I, DT)) {
+ L->SubLoops.push_back(NewLoop);
+ NewLoop->ParentLoop = L;
+ }
+
+ // Add the basic blocks that comprise this loop to the BBMap so that this
+ // loop can be found for them.
+ //
+ for (typename std::vector<BlockT*>::iterator I = L->Blocks.begin(),
+ E = L->Blocks.end(); I != E; ++I) {
+ typename std::map<BlockT*, LoopBase<BlockT>*>::iterator BBMI =
+ BBMap.lower_bound(*I);
+ if (BBMI == BBMap.end() || BBMI->first != *I) // Not in map yet...
+ BBMap.insert(BBMI, std::make_pair(*I, L)); // Must be at this level
+ }
+
+ // Now that we have a list of all of the child loops of this loop, check to
+ // see if any of them should actually be nested inside of each other. We can
+ // accidentally pull loops our of their parents, so we must make sure to
+ // organize the loop nests correctly now.
+ {
+ std::map<BlockT*, LoopBase<BlockT>*> ContainingLoops;
+ for (unsigned i = 0; i != L->SubLoops.size(); ++i) {
+ LoopBase<BlockT> *Child = L->SubLoops[i];
+ assert(Child->getParentLoop() == L && "Not proper child loop?");
+
+ if (LoopBase<BlockT> *ContainingLoop =
+ ContainingLoops[Child->getHeader()]) {
+ // If there is already a loop which contains this loop, move this loop
+ // into the containing loop.
+ MoveSiblingLoopInto(Child, ContainingLoop);
+ --i; // The loop got removed from the SubLoops list.
+ } else {
+ // This is currently considered to be a top-level loop. Check to see if
+ // any of the contained blocks are loop headers for subloops we have
+ // already processed.
+ for (unsigned b = 0, e = Child->Blocks.size(); b != e; ++b) {
+ LoopBase<BlockT> *&BlockLoop = ContainingLoops[Child->Blocks[b]];
+ if (BlockLoop == 0) { // Child block not processed yet...
+ BlockLoop = Child;
+ } else if (BlockLoop != Child) {
+ LoopBase<BlockT> *SubLoop = BlockLoop;
+ // Reparent all of the blocks which used to belong to BlockLoops
+ for (unsigned j = 0, e = SubLoop->Blocks.size(); j != e; ++j)
+ ContainingLoops[SubLoop->Blocks[j]] = Child;
+
+ // There is already a loop which contains this block, that means
+ // that we should reparent the loop which the block is currently
+ // considered to belong to to be a child of this loop.
+ MoveSiblingLoopInto(SubLoop, Child);
+ --i; // We just shrunk the SubLoops list.
+ }
+ }
+ }
+ }
+ }
+
+ return L;
+ }
+
+ /// MoveSiblingLoopInto - This method moves the NewChild loop to live inside of
+ /// the NewParent Loop, instead of being a sibling of it.
+ void MoveSiblingLoopInto(LoopBase<BlockT> *NewChild,
+ LoopBase<BlockT> *NewParent) {
+ LoopBase<BlockT> *OldParent = NewChild->getParentLoop();
+ assert(OldParent && OldParent == NewParent->getParentLoop() &&
+ NewChild != NewParent && "Not sibling loops!");
+
+ // Remove NewChild from being a child of OldParent
+ typename std::vector<LoopBase<BlockT>*>::iterator I =
+ std::find(OldParent->SubLoops.begin(), OldParent->SubLoops.end(), NewChild);
+ assert(I != OldParent->SubLoops.end() && "Parent fields incorrect??");
+ OldParent->SubLoops.erase(I); // Remove from parent's subloops list
+ NewChild->ParentLoop = 0;
+
+ InsertLoopInto(NewChild, NewParent);
+ }
+
+ /// InsertLoopInto - This inserts loop L into the specified parent loop. If the
+ /// parent loop contains a loop which should contain L, the loop gets inserted
+ /// into L instead.
+ void InsertLoopInto(LoopBase<BlockT> *L, LoopBase<BlockT> *Parent) {
+ BlockT *LHeader = L->getHeader();
+ assert(Parent->contains(LHeader) && "This loop should not be inserted here!");
+
+ // Check to see if it belongs in a child loop...
+ for (unsigned i = 0, e = Parent->SubLoops.size(); i != e; ++i)
+ if (Parent->SubLoops[i]->contains(LHeader)) {
+ InsertLoopInto(L, Parent->SubLoops[i]);
+ return;
+ }
+
+ // If not, insert it here!
+ Parent->SubLoops.push_back(L);
+ L->ParentLoop = Parent;
+ }
+
+ // Debugging
+
+ void print(std::ostream &OS, const Module* ) const {
+ for (unsigned i = 0; i < TopLevelLoops.size(); ++i)
+ TopLevelLoops[i]->print(OS);
+ #if 0
+ for (std::map<BasicBlock*, Loop*>::const_iterator I = BBMap.begin(),
+ E = BBMap.end(); I != E; ++I)
+ OS << "BB '" << I->first->getName() << "' level = "
+ << I->second->getLoopDepth() << "\n";
+ #endif
+ }
+};
+
+class LoopInfo : public FunctionPass {
+ LoopInfoBase<BasicBlock>* LI;
+ friend class LoopBase<BasicBlock>;
+
+ LoopInfoBase<BasicBlock>& getBase() { return *LI; }
+public:
+ static char ID; // Pass identification, replacement for typeid
+
+ LoopInfo() : FunctionPass(intptr_t(&ID)) {
+ LI = new LoopInfoBase<BasicBlock>();
+ }
+
+ ~LoopInfo() { LI->releaseMemory(); }
+
+ /// iterator/begin/end - The interface to the top-level loops in the current
+ /// function.
+ ///
+ typedef std::vector<Loop*>::const_iterator iterator;
+ inline iterator begin() const { return LI->begin(); }
+ inline iterator end() const { return LI->end(); }
+
+ /// getLoopFor - Return the inner most loop that BB lives in. If a basic
+ /// block is in no loop (for example the entry node), null is returned.
+ ///
+ inline Loop *getLoopFor(const BasicBlock *BB) const {
+ return LI->getLoopFor(BB);
+ }
+
+ /// operator[] - same as getLoopFor...
+ ///
+ inline const Loop *operator[](const BasicBlock *BB) const {
+ return LI->getLoopFor(BB);
+ }
+
+ /// getLoopDepth - Return the loop nesting level of the specified block...
+ ///
+ inline unsigned getLoopDepth(const BasicBlock *BB) const {
+ return LI->getLoopDepth(BB);
+ }
+
+ // isLoopHeader - True if the block is a loop header node
+ inline bool isLoopHeader(BasicBlock *BB) const {
+ return LI->isLoopHeader(BB);
+ }
/// runOnFunction - Calculate the natural loop information.
///
virtual bool runOnFunction(Function &F);
- virtual void releaseMemory();
+ virtual void releaseMemory() { LI->releaseMemory(); }
- void print(std::ostream &O, const Module* = 0) const;
- void print(std::ostream *O, const Module* M = 0) const {
- if (O) print(*O, M);
+ virtual void print(std::ostream &O, const Module* M = 0) const {
+ if (O) LI->print(O, M);
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
@@ -588,34 +882,33 @@
/// removeLoop - This removes the specified top-level loop from this loop info
/// object. The loop is not deleted, as it will presumably be inserted into
/// another loop.
- Loop *removeLoop(iterator I);
+ inline Loop *removeLoop(iterator I) { return LI->removeLoop(I); }
/// changeLoopFor - Change the top-level loop that contains BB to the
/// specified loop. This should be used by transformations that restructure
/// the loop hierarchy tree.
- void changeLoopFor(BasicBlock *BB, Loop *L);
+ inline void changeLoopFor(BasicBlock *BB, Loop *L) {
+ LI->changeLoopFor(BB, L);
+ }
/// changeTopLevelLoop - Replace the specified loop in the top-level loops
/// list with the indicated loop.
- void changeTopLevelLoop(Loop *OldLoop, Loop *NewLoop);
+ inline void changeTopLevelLoop(Loop *OldLoop, Loop *NewLoop) {
+ LI->changeTopLevelLoop(OldLoop, NewLoop);
+ }
/// addTopLevelLoop - This adds the specified loop to the collection of
/// top-level loops.
- void addTopLevelLoop(Loop *New) {
- assert(New->getParentLoop() == 0 && "Loop already in subloop!");
- TopLevelLoops.push_back(New);
+ inline void addTopLevelLoop(Loop *New) {
+ LI->addTopLevelLoop(New);
}
/// removeBlock - This method completely removes BB from all data structures,
/// including all of the Loop objects it is nested in and our mapping from
/// BasicBlocks to loops.
- void removeBlock(BasicBlock *BB);
-
-private:
- void Calculate(DominatorTree &DT);
- Loop *ConsiderForLoop(BasicBlock *BB, DominatorTree &DT);
- void MoveSiblingLoopInto(Loop *NewChild, Loop *NewParent);
- void InsertLoopInto(Loop *L, Loop *Parent);
+ void removeBlock(BasicBlock *BB) {
+ LI->removeBlock(BB);
+ }
};
@@ -647,14 +940,17 @@
};
template<class BlockT>
-void LoopBase<BlockT>::addBasicBlockToLoop(BlockT *NewBB, LoopInfo &LI) {
+void LoopBase<BlockT>::addBasicBlockToLoop(BlockT *NewBB,
+ LoopInfo &LI) {
assert((Blocks.empty() || LI[getHeader()] == this) &&
"Incorrect LI specified for this loop!");
assert(NewBB && "Cannot add a null basic block to the loop!");
assert(LI[NewBB] == 0 && "BasicBlock already in the loop!");
+ LoopInfoBase<BasicBlock>& LIB = LI.getBase();
+
// Add the loop mapping to the LoopInfo object...
- LI.BBMap[NewBB] = this;
+ LIB.BBMap[NewBB] = this;
// Add the basic block to this loop and all parent loops...
LoopBase<BlockT> *L = this;
Modified: llvm/trunk/lib/Analysis/LoopInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/LoopInfo.cpp?rev=44158&r1=44157&r2=44158&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/LoopInfo.cpp (original)
+++ llvm/trunk/lib/Analysis/LoopInfo.cpp Wed Nov 14 23:00:15 2007
@@ -43,243 +43,14 @@
//
bool LoopInfo::runOnFunction(Function &) {
releaseMemory();
- Calculate(getAnalysis<DominatorTree>()); // Update
+ LI->Calculate(getAnalysis<DominatorTree>()); // Update
return false;
}
-void LoopInfo::releaseMemory() {
- for (std::vector<Loop*>::iterator I = TopLevelLoops.begin(),
- E = TopLevelLoops.end(); I != E; ++I)
- delete *I; // Delete all of the loops...
-
- BBMap.clear(); // Reset internal state of analysis
- TopLevelLoops.clear();
-}
-
-void LoopInfo::Calculate(DominatorTree &DT) {
- BasicBlock *RootNode = DT.getRootNode()->getBlock();
-
- for (df_iterator<BasicBlock*> NI = df_begin(RootNode),
- NE = df_end(RootNode); NI != NE; ++NI)
- if (Loop *L = ConsiderForLoop(*NI, DT))
- TopLevelLoops.push_back(L);
-}
-
void LoopInfo::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<DominatorTree>();
}
-void LoopInfo::print(std::ostream &OS, const Module* ) const {
- for (unsigned i = 0; i < TopLevelLoops.size(); ++i)
- TopLevelLoops[i]->print(OS);
-#if 0
- for (std::map<BasicBlock*, Loop*>::const_iterator I = BBMap.begin(),
- E = BBMap.end(); I != E; ++I)
- OS << "BB '" << I->first->getName() << "' level = "
- << I->second->getLoopDepth() << "\n";
-#endif
-}
-
-static bool isNotAlreadyContainedIn(Loop *SubLoop, Loop *ParentLoop) {
- if (SubLoop == 0) return true;
- if (SubLoop == ParentLoop) return false;
- return isNotAlreadyContainedIn(SubLoop->getParentLoop(), ParentLoop);
-}
-
-Loop *LoopInfo::ConsiderForLoop(BasicBlock *BB, DominatorTree &DT) {
- if (BBMap.find(BB) != BBMap.end()) return 0; // Haven't processed this node?
-
- std::vector<BasicBlock *> TodoStack;
-
- // Scan the predecessors of BB, checking to see if BB dominates any of
- // them. This identifies backedges which target this node...
- for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I)
- if (DT.dominates(BB, *I)) // If BB dominates it's predecessor...
- TodoStack.push_back(*I);
-
- if (TodoStack.empty()) return 0; // No backedges to this block...
-
- // Create a new loop to represent this basic block...
- Loop *L = new Loop(BB);
- BBMap[BB] = L;
-
- BasicBlock *EntryBlock = &BB->getParent()->getEntryBlock();
-
- while (!TodoStack.empty()) { // Process all the nodes in the loop
- BasicBlock *X = TodoStack.back();
- TodoStack.pop_back();
-
- if (!L->contains(X) && // As of yet unprocessed??
- DT.dominates(EntryBlock, X)) { // X is reachable from entry block?
- // Check to see if this block already belongs to a loop. If this occurs
- // then we have a case where a loop that is supposed to be a child of the
- // current loop was processed before the current loop. When this occurs,
- // this child loop gets added to a part of the current loop, making it a
- // sibling to the current loop. We have to reparent this loop.
- if (Loop *SubLoop = const_cast<Loop*>(getLoopFor(X)))
- if (SubLoop->getHeader() == X && isNotAlreadyContainedIn(SubLoop, L)) {
- // Remove the subloop from it's current parent...
- assert(SubLoop->ParentLoop && SubLoop->ParentLoop != L);
- Loop *SLP = SubLoop->ParentLoop; // SubLoopParent
- std::vector<Loop*>::iterator I =
- std::find(SLP->SubLoops.begin(), SLP->SubLoops.end(), SubLoop);
- assert(I != SLP->SubLoops.end() && "SubLoop not a child of parent?");
- SLP->SubLoops.erase(I); // Remove from parent...
-
- // Add the subloop to THIS loop...
- SubLoop->ParentLoop = L;
- L->SubLoops.push_back(SubLoop);
- }
-
- // Normal case, add the block to our loop...
- L->Blocks.push_back(X);
-
- // Add all of the predecessors of X to the end of the work stack...
- TodoStack.insert(TodoStack.end(), pred_begin(X), pred_end(X));
- }
- }
-
- // If there are any loops nested within this loop, create them now!
- for (std::vector<BasicBlock*>::iterator I = L->Blocks.begin(),
- E = L->Blocks.end(); I != E; ++I)
- if (Loop *NewLoop = ConsiderForLoop(*I, DT)) {
- L->SubLoops.push_back(NewLoop);
- NewLoop->ParentLoop = L;
- }
-
- // Add the basic blocks that comprise this loop to the BBMap so that this
- // loop can be found for them.
- //
- for (std::vector<BasicBlock*>::iterator I = L->Blocks.begin(),
- E = L->Blocks.end(); I != E; ++I) {
- std::map<BasicBlock*, Loop*>::iterator BBMI = BBMap.lower_bound(*I);
- if (BBMI == BBMap.end() || BBMI->first != *I) // Not in map yet...
- BBMap.insert(BBMI, std::make_pair(*I, L)); // Must be at this level
- }
-
- // Now that we have a list of all of the child loops of this loop, check to
- // see if any of them should actually be nested inside of each other. We can
- // accidentally pull loops our of their parents, so we must make sure to
- // organize the loop nests correctly now.
- {
- std::map<BasicBlock*, Loop*> ContainingLoops;
- for (unsigned i = 0; i != L->SubLoops.size(); ++i) {
- Loop *Child = L->SubLoops[i];
- assert(Child->getParentLoop() == L && "Not proper child loop?");
-
- if (Loop *ContainingLoop = ContainingLoops[Child->getHeader()]) {
- // If there is already a loop which contains this loop, move this loop
- // into the containing loop.
- MoveSiblingLoopInto(Child, ContainingLoop);
- --i; // The loop got removed from the SubLoops list.
- } else {
- // This is currently considered to be a top-level loop. Check to see if
- // any of the contained blocks are loop headers for subloops we have
- // already processed.
- for (unsigned b = 0, e = Child->Blocks.size(); b != e; ++b) {
- Loop *&BlockLoop = ContainingLoops[Child->Blocks[b]];
- if (BlockLoop == 0) { // Child block not processed yet...
- BlockLoop = Child;
- } else if (BlockLoop != Child) {
- Loop *SubLoop = BlockLoop;
- // Reparent all of the blocks which used to belong to BlockLoops
- for (unsigned j = 0, e = SubLoop->Blocks.size(); j != e; ++j)
- ContainingLoops[SubLoop->Blocks[j]] = Child;
-
- // There is already a loop which contains this block, that means
- // that we should reparent the loop which the block is currently
- // considered to belong to to be a child of this loop.
- MoveSiblingLoopInto(SubLoop, Child);
- --i; // We just shrunk the SubLoops list.
- }
- }
- }
- }
- }
-
- return L;
-}
-
-/// MoveSiblingLoopInto - This method moves the NewChild loop to live inside of
-/// the NewParent Loop, instead of being a sibling of it.
-void LoopInfo::MoveSiblingLoopInto(Loop *NewChild, Loop *NewParent) {
- Loop *OldParent = NewChild->getParentLoop();
- assert(OldParent && OldParent == NewParent->getParentLoop() &&
- NewChild != NewParent && "Not sibling loops!");
-
- // Remove NewChild from being a child of OldParent
- std::vector<Loop*>::iterator I =
- std::find(OldParent->SubLoops.begin(), OldParent->SubLoops.end(), NewChild);
- assert(I != OldParent->SubLoops.end() && "Parent fields incorrect??");
- OldParent->SubLoops.erase(I); // Remove from parent's subloops list
- NewChild->ParentLoop = 0;
-
- InsertLoopInto(NewChild, NewParent);
-}
-
-/// InsertLoopInto - This inserts loop L into the specified parent loop. If the
-/// parent loop contains a loop which should contain L, the loop gets inserted
-/// into L instead.
-void LoopInfo::InsertLoopInto(Loop *L, Loop *Parent) {
- BasicBlock *LHeader = L->getHeader();
- assert(Parent->contains(LHeader) && "This loop should not be inserted here!");
-
- // Check to see if it belongs in a child loop...
- for (unsigned i = 0, e = Parent->SubLoops.size(); i != e; ++i)
- if (Parent->SubLoops[i]->contains(LHeader)) {
- InsertLoopInto(L, Parent->SubLoops[i]);
- return;
- }
-
- // If not, insert it here!
- Parent->SubLoops.push_back(L);
- L->ParentLoop = Parent;
-}
-
-/// changeLoopFor - Change the top-level loop that contains BB to the
-/// specified loop. This should be used by transformations that restructure
-/// the loop hierarchy tree.
-void LoopInfo::changeLoopFor(BasicBlock *BB, Loop *L) {
- Loop *&OldLoop = BBMap[BB];
- assert(OldLoop && "Block not in a loop yet!");
- OldLoop = L;
-}
-
-/// changeTopLevelLoop - Replace the specified loop in the top-level loops
-/// list with the indicated loop.
-void LoopInfo::changeTopLevelLoop(Loop *OldLoop, Loop *NewLoop) {
- std::vector<Loop*>::iterator I = std::find(TopLevelLoops.begin(),
- TopLevelLoops.end(), OldLoop);
- assert(I != TopLevelLoops.end() && "Old loop not at top level!");
- *I = NewLoop;
- assert(NewLoop->ParentLoop == 0 && OldLoop->ParentLoop == 0 &&
- "Loops already embedded into a subloop!");
-}
-
-/// removeLoop - This removes the specified top-level loop from this loop info
-/// object. The loop is not deleted, as it will presumably be inserted into
-/// another loop.
-Loop *LoopInfo::removeLoop(iterator I) {
- assert(I != end() && "Cannot remove end iterator!");
- Loop *L = *I;
- assert(L->getParentLoop() == 0 && "Not a top-level loop!");
- TopLevelLoops.erase(TopLevelLoops.begin() + (I-begin()));
- return L;
-}
-
-/// removeBlock - This method completely removes BB from all data structures,
-/// including all of the Loop objects it is nested in and our mapping from
-/// BasicBlocks to loops.
-void LoopInfo::removeBlock(BasicBlock *BB) {
- std::map<BasicBlock *, Loop*>::iterator I = BBMap.find(BB);
- if (I != BBMap.end()) {
- for (Loop *L = I->second; L; L = L->getParentLoop())
- L->removeBlockFromLoop(BB);
-
- BBMap.erase(I);
- }
-}
-
// Ensure this file gets linked when LoopInfo.h is used.
DEFINING_FILE_FOR(LoopInfo)
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