mirror of
https://github.com/c64scene-ar/llvm-6502.git
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More templatization.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44158 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson
parent
b7e6b1ab70
commit
44a95e06cc
@ -33,9 +33,11 @@
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#include "llvm/Pass.h"
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#include "llvm/Constants.h"
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#include "llvm/Instructions.h"
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#include "llvm/ADT/DepthFirstIterator.h"
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#include "llvm/ADT/GraphTraits.h"
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#include "llvm/ADT/SmallPtrSet.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/Analysis/Dominators.h"
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#include "llvm/Support/CFG.h"
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#include "llvm/Support/Streams.h"
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#include <algorithm>
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@ -54,6 +56,7 @@ class DominatorTree;
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class LoopInfo;
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class PHINode;
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class Instruction;
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template<class N> class LoopInfoBase;
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//===----------------------------------------------------------------------===//
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/// LoopBase class - Instances of this class are used to represent loops that are
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@ -513,7 +516,7 @@ public:
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}
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private:
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friend class LoopInfo;
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friend class LoopInfoBase<BlockT>;
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LoopBase(BlockT *BB) : ParentLoop(0) {
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Blocks.push_back(BB);
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}
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@ -526,61 +529,352 @@ typedef LoopBase<BasicBlock> Loop;
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/// LoopInfo - This class builds and contains all of the top level loop
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/// structures in the specified function.
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///
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class LoopInfo : public FunctionPass {
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template<class BlockT>
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class LoopInfoBase {
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// BBMap - Mapping of basic blocks to the inner most loop they occur in
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std::map<BasicBlock*, Loop*> BBMap;
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std::vector<Loop*> TopLevelLoops;
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friend class LoopBase<BasicBlock>;
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std::map<BlockT*, Loop*> BBMap;
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std::vector<LoopBase<BlockT>*> TopLevelLoops;
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friend class LoopBase<BlockT>;
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public:
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static char ID; // Pass identification, replacement for typeid
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LoopInfo() : FunctionPass(intptr_t(&ID)) {}
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~LoopInfo() { releaseMemory(); }
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LoopInfoBase() { }
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~LoopInfoBase() { releaseMemory(); }
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void releaseMemory() {
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for (typename std::vector<LoopBase<BlockT>* >::iterator I =
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TopLevelLoops.begin(), E = TopLevelLoops.end(); I != E; ++I)
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delete *I; // Delete all of the loops...
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BBMap.clear(); // Reset internal state of analysis
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TopLevelLoops.clear();
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}
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/// iterator/begin/end - The interface to the top-level loops in the current
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/// function.
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///
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typedef std::vector<Loop*>::const_iterator iterator;
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typedef typename std::vector<LoopBase<BlockT>*>::const_iterator iterator;
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iterator begin() const { return TopLevelLoops.begin(); }
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iterator end() const { return TopLevelLoops.end(); }
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/// getLoopFor - Return the inner most loop that BB lives in. If a basic
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/// block is in no loop (for example the entry node), null is returned.
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///
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Loop *getLoopFor(const BasicBlock *BB) const {
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std::map<BasicBlock *, Loop*>::const_iterator I=
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LoopBase<BlockT> *getLoopFor(const BlockT *BB) const {
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typename std::map<BlockT *, LoopBase<BlockT>*>::const_iterator I=
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BBMap.find(const_cast<BasicBlock*>(BB));
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return I != BBMap.end() ? I->second : 0;
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}
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/// operator[] - same as getLoopFor...
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///
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const Loop *operator[](const BasicBlock *BB) const {
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const LoopBase<BlockT> *operator[](const BlockT *BB) const {
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return getLoopFor(BB);
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}
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/// getLoopDepth - Return the loop nesting level of the specified block...
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///
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unsigned getLoopDepth(const BasicBlock *BB) const {
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unsigned getLoopDepth(const BlockT *BB) const {
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const Loop *L = getLoopFor(BB);
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return L ? L->getLoopDepth() : 0;
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}
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// isLoopHeader - True if the block is a loop header node
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bool isLoopHeader(BasicBlock *BB) const {
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bool isLoopHeader(BlockT *BB) const {
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const Loop *L = getLoopFor(BB);
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return L && L->getHeader() == BB;
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}
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/// removeLoop - This removes the specified top-level loop from this loop info
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/// object. The loop is not deleted, as it will presumably be inserted into
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/// another loop.
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LoopBase<BlockT> *removeLoop(iterator I) {
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assert(I != end() && "Cannot remove end iterator!");
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LoopBase<BlockT> *L = *I;
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assert(L->getParentLoop() == 0 && "Not a top-level loop!");
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TopLevelLoops.erase(TopLevelLoops.begin() + (I-begin()));
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return L;
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}
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/// changeLoopFor - Change the top-level loop that contains BB to the
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/// specified loop. This should be used by transformations that restructure
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/// the loop hierarchy tree.
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void changeLoopFor(BlockT *BB, LoopBase<BlockT> *L) {
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LoopBase<BlockT> *&OldLoop = BBMap[BB];
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assert(OldLoop && "Block not in a loop yet!");
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OldLoop = L;
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}
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/// changeTopLevelLoop - Replace the specified loop in the top-level loops
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/// list with the indicated loop.
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void changeTopLevelLoop(LoopBase<BlockT> *OldLoop,
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LoopBase<BlockT> *NewLoop) {
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typename std::vector<LoopBase<BlockT>*>::iterator I =
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std::find(TopLevelLoops.begin(), TopLevelLoops.end(), OldLoop);
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assert(I != TopLevelLoops.end() && "Old loop not at top level!");
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*I = NewLoop;
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assert(NewLoop->ParentLoop == 0 && OldLoop->ParentLoop == 0 &&
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"Loops already embedded into a subloop!");
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}
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/// addTopLevelLoop - This adds the specified loop to the collection of
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/// top-level loops.
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void addTopLevelLoop(LoopBase<BlockT> *New) {
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assert(New->getParentLoop() == 0 && "Loop already in subloop!");
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TopLevelLoops.push_back(New);
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}
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/// removeBlock - This method completely removes BB from all data structures,
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/// including all of the Loop objects it is nested in and our mapping from
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/// BasicBlocks to loops.
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void removeBlock(BlockT *BB) {
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typename std::map<BlockT *, LoopBase<BlockT>*>::iterator I = BBMap.find(BB);
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if (I != BBMap.end()) {
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for (Loop *L = I->second; L; L = L->getParentLoop())
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L->removeBlockFromLoop(BB);
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BBMap.erase(I);
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}
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}
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// Internals
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static bool isNotAlreadyContainedIn(Loop *SubLoop, Loop *ParentLoop) {
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if (SubLoop == 0) return true;
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if (SubLoop == ParentLoop) return false;
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return isNotAlreadyContainedIn(SubLoop->getParentLoop(), ParentLoop);
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}
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void Calculate(DominatorTree &DT) {
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BlockT *RootNode = DT.getRootNode()->getBlock();
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for (df_iterator<BlockT*> NI = df_begin(RootNode),
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NE = df_end(RootNode); NI != NE; ++NI)
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if (LoopBase<BlockT> *L = ConsiderForLoop(*NI, DT))
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TopLevelLoops.push_back(L);
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}
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LoopBase<BlockT> *ConsiderForLoop(BlockT *BB, DominatorTree &DT) {
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if (BBMap.find(BB) != BBMap.end()) return 0;// Haven't processed this node?
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std::vector<BlockT *> TodoStack;
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// Scan the predecessors of BB, checking to see if BB dominates any of
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// them. This identifies backedges which target this node...
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for (pred_iterator I = pred_begin(BB), E = pred_end(BB); I != E; ++I)
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if (DT.dominates(BB, *I)) // If BB dominates it's predecessor...
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TodoStack.push_back(*I);
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if (TodoStack.empty()) return 0; // No backedges to this block...
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// Create a new loop to represent this basic block...
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LoopBase<BlockT> *L = new LoopBase<BlockT>(BB);
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BBMap[BB] = L;
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BlockT *EntryBlock = &BB->getParent()->getEntryBlock();
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while (!TodoStack.empty()) { // Process all the nodes in the loop
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BlockT *X = TodoStack.back();
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TodoStack.pop_back();
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if (!L->contains(X) && // As of yet unprocessed??
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DT.dominates(EntryBlock, X)) { // X is reachable from entry block?
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// Check to see if this block already belongs to a loop. If this occurs
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// then we have a case where a loop that is supposed to be a child of the
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// current loop was processed before the current loop. When this occurs,
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// this child loop gets added to a part of the current loop, making it a
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// sibling to the current loop. We have to reparent this loop.
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if (LoopBase<BlockT> *SubLoop =
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const_cast<LoopBase<BlockT>*>(getLoopFor(X)))
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if (SubLoop->getHeader() == X && isNotAlreadyContainedIn(SubLoop, L)) {
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// Remove the subloop from it's current parent...
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assert(SubLoop->ParentLoop && SubLoop->ParentLoop != L);
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LoopBase<BlockT> *SLP = SubLoop->ParentLoop; // SubLoopParent
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typename std::vector<LoopBase<BlockT>*>::iterator I =
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std::find(SLP->SubLoops.begin(), SLP->SubLoops.end(), SubLoop);
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assert(I != SLP->SubLoops.end() && "SubLoop not a child of parent?");
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SLP->SubLoops.erase(I); // Remove from parent...
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// Add the subloop to THIS loop...
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SubLoop->ParentLoop = L;
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L->SubLoops.push_back(SubLoop);
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}
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// Normal case, add the block to our loop...
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L->Blocks.push_back(X);
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// Add all of the predecessors of X to the end of the work stack...
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TodoStack.insert(TodoStack.end(), pred_begin(X), pred_end(X));
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}
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}
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// If there are any loops nested within this loop, create them now!
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for (typename std::vector<BlockT*>::iterator I = L->Blocks.begin(),
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E = L->Blocks.end(); I != E; ++I)
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if (LoopBase<BlockT> *NewLoop = ConsiderForLoop(*I, DT)) {
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L->SubLoops.push_back(NewLoop);
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NewLoop->ParentLoop = L;
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}
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// Add the basic blocks that comprise this loop to the BBMap so that this
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// loop can be found for them.
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//
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for (typename std::vector<BlockT*>::iterator I = L->Blocks.begin(),
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E = L->Blocks.end(); I != E; ++I) {
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typename std::map<BlockT*, LoopBase<BlockT>*>::iterator BBMI =
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BBMap.lower_bound(*I);
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if (BBMI == BBMap.end() || BBMI->first != *I) // Not in map yet...
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BBMap.insert(BBMI, std::make_pair(*I, L)); // Must be at this level
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}
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// Now that we have a list of all of the child loops of this loop, check to
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// see if any of them should actually be nested inside of each other. We can
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// accidentally pull loops our of their parents, so we must make sure to
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// organize the loop nests correctly now.
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{
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std::map<BlockT*, LoopBase<BlockT>*> ContainingLoops;
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for (unsigned i = 0; i != L->SubLoops.size(); ++i) {
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LoopBase<BlockT> *Child = L->SubLoops[i];
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assert(Child->getParentLoop() == L && "Not proper child loop?");
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if (LoopBase<BlockT> *ContainingLoop =
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ContainingLoops[Child->getHeader()]) {
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// If there is already a loop which contains this loop, move this loop
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// into the containing loop.
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MoveSiblingLoopInto(Child, ContainingLoop);
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--i; // The loop got removed from the SubLoops list.
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} else {
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// This is currently considered to be a top-level loop. Check to see if
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// any of the contained blocks are loop headers for subloops we have
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// already processed.
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for (unsigned b = 0, e = Child->Blocks.size(); b != e; ++b) {
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LoopBase<BlockT> *&BlockLoop = ContainingLoops[Child->Blocks[b]];
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if (BlockLoop == 0) { // Child block not processed yet...
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BlockLoop = Child;
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} else if (BlockLoop != Child) {
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LoopBase<BlockT> *SubLoop = BlockLoop;
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// Reparent all of the blocks which used to belong to BlockLoops
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for (unsigned j = 0, e = SubLoop->Blocks.size(); j != e; ++j)
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ContainingLoops[SubLoop->Blocks[j]] = Child;
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// There is already a loop which contains this block, that means
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// that we should reparent the loop which the block is currently
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// considered to belong to to be a child of this loop.
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MoveSiblingLoopInto(SubLoop, Child);
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--i; // We just shrunk the SubLoops list.
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}
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}
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}
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}
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}
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return L;
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}
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/// MoveSiblingLoopInto - This method moves the NewChild loop to live inside of
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/// the NewParent Loop, instead of being a sibling of it.
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void MoveSiblingLoopInto(LoopBase<BlockT> *NewChild,
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LoopBase<BlockT> *NewParent) {
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LoopBase<BlockT> *OldParent = NewChild->getParentLoop();
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assert(OldParent && OldParent == NewParent->getParentLoop() &&
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NewChild != NewParent && "Not sibling loops!");
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// Remove NewChild from being a child of OldParent
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typename std::vector<LoopBase<BlockT>*>::iterator I =
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std::find(OldParent->SubLoops.begin(), OldParent->SubLoops.end(), NewChild);
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assert(I != OldParent->SubLoops.end() && "Parent fields incorrect??");
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OldParent->SubLoops.erase(I); // Remove from parent's subloops list
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NewChild->ParentLoop = 0;
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InsertLoopInto(NewChild, NewParent);
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}
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/// InsertLoopInto - This inserts loop L into the specified parent loop. If the
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/// parent loop contains a loop which should contain L, the loop gets inserted
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/// into L instead.
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void InsertLoopInto(LoopBase<BlockT> *L, LoopBase<BlockT> *Parent) {
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BlockT *LHeader = L->getHeader();
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assert(Parent->contains(LHeader) && "This loop should not be inserted here!");
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// Check to see if it belongs in a child loop...
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for (unsigned i = 0, e = Parent->SubLoops.size(); i != e; ++i)
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if (Parent->SubLoops[i]->contains(LHeader)) {
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InsertLoopInto(L, Parent->SubLoops[i]);
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return;
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}
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// If not, insert it here!
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Parent->SubLoops.push_back(L);
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L->ParentLoop = Parent;
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}
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// Debugging
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void print(std::ostream &OS, const Module* ) const {
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for (unsigned i = 0; i < TopLevelLoops.size(); ++i)
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TopLevelLoops[i]->print(OS);
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#if 0
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for (std::map<BasicBlock*, Loop*>::const_iterator I = BBMap.begin(),
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E = BBMap.end(); I != E; ++I)
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OS << "BB '" << I->first->getName() << "' level = "
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<< I->second->getLoopDepth() << "\n";
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#endif
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}
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};
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class LoopInfo : public FunctionPass {
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LoopInfoBase<BasicBlock>* LI;
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friend class LoopBase<BasicBlock>;
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LoopInfoBase<BasicBlock>& getBase() { return *LI; }
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public:
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static char ID; // Pass identification, replacement for typeid
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LoopInfo() : FunctionPass(intptr_t(&ID)) {
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LI = new LoopInfoBase<BasicBlock>();
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}
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~LoopInfo() { LI->releaseMemory(); }
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/// iterator/begin/end - The interface to the top-level loops in the current
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/// function.
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///
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typedef std::vector<Loop*>::const_iterator iterator;
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inline iterator begin() const { return LI->begin(); }
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inline iterator end() const { return LI->end(); }
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/// getLoopFor - Return the inner most loop that BB lives in. If a basic
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/// block is in no loop (for example the entry node), null is returned.
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///
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inline Loop *getLoopFor(const BasicBlock *BB) const {
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return LI->getLoopFor(BB);
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}
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/// operator[] - same as getLoopFor...
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///
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inline const Loop *operator[](const BasicBlock *BB) const {
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return LI->getLoopFor(BB);
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}
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/// getLoopDepth - Return the loop nesting level of the specified block...
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///
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inline unsigned getLoopDepth(const BasicBlock *BB) const {
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return LI->getLoopDepth(BB);
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}
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// isLoopHeader - True if the block is a loop header node
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inline bool isLoopHeader(BasicBlock *BB) const {
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return LI->isLoopHeader(BB);
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}
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/// runOnFunction - Calculate the natural loop information.
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///
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virtual bool runOnFunction(Function &F);
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virtual void releaseMemory();
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virtual void releaseMemory() { LI->releaseMemory(); }
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void print(std::ostream &O, const Module* = 0) const;
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void print(std::ostream *O, const Module* M = 0) const {
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if (O) print(*O, M);
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virtual void print(std::ostream &O, const Module* M = 0) const {
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if (O) LI->print(O, M);
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}
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virtual void getAnalysisUsage(AnalysisUsage &AU) const;
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@ -588,34 +882,33 @@ public:
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/// removeLoop - This removes the specified top-level loop from this loop info
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/// object. The loop is not deleted, as it will presumably be inserted into
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/// another loop.
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Loop *removeLoop(iterator I);
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inline Loop *removeLoop(iterator I) { return LI->removeLoop(I); }
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/// changeLoopFor - Change the top-level loop that contains BB to the
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/// specified loop. This should be used by transformations that restructure
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/// the loop hierarchy tree.
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void changeLoopFor(BasicBlock *BB, Loop *L);
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inline void changeLoopFor(BasicBlock *BB, Loop *L) {
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LI->changeLoopFor(BB, L);
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}
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/// changeTopLevelLoop - Replace the specified loop in the top-level loops
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/// list with the indicated loop.
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void changeTopLevelLoop(Loop *OldLoop, Loop *NewLoop);
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inline void changeTopLevelLoop(Loop *OldLoop, Loop *NewLoop) {
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LI->changeTopLevelLoop(OldLoop, NewLoop);
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}
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/// addTopLevelLoop - This adds the specified loop to the collection of
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/// top-level loops.
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void addTopLevelLoop(Loop *New) {
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assert(New->getParentLoop() == 0 && "Loop already in subloop!");
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TopLevelLoops.push_back(New);
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inline void addTopLevelLoop(Loop *New) {
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LI->addTopLevelLoop(New);
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}
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/// 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 <> struct GraphTraits<Loop*> {
|
||||
};
|
||||
|
||||
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;
|
||||
|
||||
@ -43,243 +43,14 @@ X("loops", "Natural Loop Construction", true);
|
||||
//
|
||||
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)
|
||||
|
||||
Loading…
Reference in New Issue
Block a user