Author: resistor
Date: Tue Nov 13 20:33:58 2007
New Revision: 44097
URL: http://llvm.org/viewvc/llvm-project?rev=44097&view=rev
Log:
Start the process of making MachineLoopInfo possible by templating Loop.
Modified:
llvm/trunk/include/llvm/Analysis/LoopInfo.h
llvm/trunk/include/llvm/Analysis/LoopPass.h
llvm/trunk/include/llvm/Analysis/ScalarEvolution.h
llvm/trunk/include/llvm/Transforms/Utils/Cloning.h
llvm/trunk/include/llvm/Transforms/Utils/FunctionUtils.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=44097&r1=44096&r2=44097&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/LoopInfo.h (original)
+++ llvm/trunk/include/llvm/Analysis/LoopInfo.h Tue Nov 13 20:33:58 2007
@@ -31,8 +31,22 @@
#define LLVM_ANALYSIS_LOOP_INFO_H
#include "llvm/Pass.h"
+#include "llvm/Constants.h"
+#include "llvm/Instructions.h"
#include "llvm/ADT/GraphTraits.h"
+#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/CFG.h"
+#include "llvm/Support/Streams.h"
+#include <algorithm>
+#include <ostream>
+
+template<typename T>
+static void RemoveFromVector(std::vector<T*> &V, T *N) {
+ typename std::vector<T*>::iterator I = std::find(V.begin(), V.end(), N);
+ assert(I != V.end() && "N is not in this list!");
+ V.erase(I);
+}
namespace llvm {
@@ -42,64 +56,88 @@
class Instruction;
//===----------------------------------------------------------------------===//
-/// Loop class - Instances of this class are used to represent loops that are
+/// LoopBase class - Instances of this class are used to represent loops that
are
/// detected in the flow graph
///
-class Loop {
- Loop *ParentLoop;
- std::vector<Loop*> SubLoops; // Loops contained entirely within this
one
- std::vector<BasicBlock*> Blocks; // First entry is the header node
+template<class BlockT>
+class LoopBase {
+ LoopBase<BlockT> *ParentLoop;
+ std::vector<LoopBase<BlockT>*> SubLoops; // Loops contained entirely
within this one
+ std::vector<BlockT*> Blocks; // First entry is the header node
- Loop(const Loop &); // DO NOT IMPLEMENT
- const Loop &operator=(const Loop &); // DO NOT IMPLEMENT
+ LoopBase(const LoopBase<BlockT> &); // DO NOT IMPLEMENT
+ const LoopBase<BlockT> &operator=(const LoopBase<BlockT> &); // DO NOT
IMPLEMENT
public:
/// Loop ctor - This creates an empty loop.
- Loop() : ParentLoop(0) {}
- ~Loop() {
+ LoopBase() : ParentLoop(0) {}
+ ~LoopBase() {
for (unsigned i = 0, e = SubLoops.size(); i != e; ++i)
delete SubLoops[i];
}
unsigned getLoopDepth() const {
unsigned D = 0;
- for (const Loop *CurLoop = this; CurLoop; CurLoop = CurLoop->ParentLoop)
+ for (const LoopBase<BlockT> *CurLoop = this; CurLoop;
+ CurLoop = CurLoop->ParentLoop)
++D;
return D;
}
- BasicBlock *getHeader() const { return Blocks.front(); }
- Loop *getParentLoop() const { return ParentLoop; }
+ BlockT *getHeader() const { return Blocks.front(); }
+ LoopBase<BlockT> *getParentLoop() const { return ParentLoop; }
/// contains - Return true of the specified basic block is in this loop
///
- bool contains(const BasicBlock *BB) const;
+ bool contains(const BlockT *BB) const {
+ return std::find(Blocks.begin(), Blocks.end(), BB) != Blocks.end();
+ }
/// iterator/begin/end - Return the loops contained entirely within this
loop.
///
- const std::vector<Loop*> &getSubLoops() const { return SubLoops; }
- typedef std::vector<Loop*>::const_iterator iterator;
+ const std::vector<LoopBase<BlockT>*> &getSubLoops() const { return SubLoops;
}
+ typedef typename std::vector<LoopBase<BlockT>*>::const_iterator iterator;
iterator begin() const { return SubLoops.begin(); }
iterator end() const { return SubLoops.end(); }
bool empty() const { return SubLoops.empty(); }
/// getBlocks - Get a list of the basic blocks which make up this loop.
///
- const std::vector<BasicBlock*> &getBlocks() const { return Blocks; }
- typedef std::vector<BasicBlock*>::const_iterator block_iterator;
+ const std::vector<BlockT*> &getBlocks() const { return Blocks; }
+ typedef typename std::vector<BlockT*>::const_iterator block_iterator;
block_iterator block_begin() const { return Blocks.begin(); }
block_iterator block_end() const { return Blocks.end(); }
/// isLoopExit - True if terminator in the block can branch to another block
/// that is outside of the current loop.
///
- bool isLoopExit(const BasicBlock *BB) const;
+ bool isLoopExit(const BlockT *BB) const {
+ for (succ_const_iterator SI = succ_begin(BB), SE = succ_end(BB);
+ SI != SE; ++SI) {
+ if (!contains(*SI))
+ return true;
+ }
+ return false;
+ }
/// getNumBackEdges - Calculate the number of back edges to the loop header
///
- unsigned getNumBackEdges() const;
+ unsigned getNumBackEdges() const {
+ unsigned NumBackEdges = 0;
+ BlockT *H = getHeader();
+
+ for (pred_iterator I = pred_begin(H), E = pred_end(H); I != E; ++I)
+ if (contains(*I))
+ ++NumBackEdges;
+
+ return NumBackEdges;
+ }
/// isLoopInvariant - Return true if the specified value is loop invariant
///
- bool isLoopInvariant(Value *V) const;
+ bool isLoopInvariant(Value *V) const {
+ if (Instruction *I = dyn_cast<Instruction>(V))
+ return !contains(I->getParent());
+ return true; // All non-instructions are loop invariant
+ }
//===--------------------------------------------------------------------===//
// APIs for simple analysis of the loop.
@@ -113,18 +151,91 @@
/// outside of the loop. These are the blocks _inside of the current loop_
/// which branch out. The returned list is always unique.
///
- void getExitingBlocks(SmallVectorImpl<BasicBlock *> &Blocks) const;
+ void getExitingBlocks(SmallVectorImpl<BlockT *> &ExitingBlocks) const {
+ // Sort the blocks vector so that we can use binary search to do quick
+ // lookups.
+ SmallVector<BlockT*, 128> LoopBBs(block_begin(), block_end());
+ std::sort(LoopBBs.begin(), LoopBBs.end());
+
+ for (typename std::vector<BlockT*>::const_iterator BI = Blocks.begin(),
+ BE = Blocks.end(); BI != BE; ++BI)
+ for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I)
+ if (!std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I)) {
+ // Not in current loop? It must be an exit block.
+ ExitingBlocks.push_back(*BI);
+ break;
+ }
+ }
/// getExitBlocks - Return all of the successor blocks of this loop. These
/// are the blocks _outside of the current loop_ which are branched to.
///
- void getExitBlocks(SmallVectorImpl<BasicBlock* > &Blocks) const;
+ void getExitBlocks(SmallVectorImpl<BlockT*> &ExitBlocks) const {
+ // Sort the blocks vector so that we can use binary search to do quick
+ // lookups.
+ SmallVector<BlockT*, 128> LoopBBs(block_begin(), block_end());
+ std::sort(LoopBBs.begin(), LoopBBs.end());
+
+ for (typename std::vector<BlockT*>::const_iterator BI = Blocks.begin(),
+ BE = Blocks.end(); BI != BE; ++BI)
+ for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I)
+ if (!std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I))
+ // Not in current loop? It must be an exit block.
+ ExitBlocks.push_back(*I);
+ }
/// getUniqueExitBlocks - Return all unique successor blocks of this loop.
/// These are the blocks _outside of the current loop_ which are branched to.
/// This assumes that loop is in canonical form.
///
- void getUniqueExitBlocks(SmallVectorImpl<BasicBlock*> &ExitBlocks) const;
+ void getUniqueExitBlocks(SmallVectorImpl<BlockT*> &ExitBlocks) const {
+ // Sort the blocks vector so that we can use binary search to do quick
+ // lookups.
+ SmallVector<BlockT*, 128> LoopBBs(block_begin(), block_end());
+ std::sort(LoopBBs.begin(), LoopBBs.end());
+
+ std::vector<BlockT*> switchExitBlocks;
+
+ for (typename std::vector<BlockT*>::const_iterator BI = Blocks.begin(),
+ BE = Blocks.end(); BI != BE; ++BI) {
+
+ BlockT *current = *BI;
+ switchExitBlocks.clear();
+
+ for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I) {
+ if (std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I))
+ // If block is inside the loop then it is not a exit block.
+ continue;
+
+ pred_iterator PI = pred_begin(*I);
+ BlockT *firstPred = *PI;
+
+ // If current basic block is this exit block's first predecessor
+ // then only insert exit block in to the output ExitBlocks vector.
+ // This ensures that same exit block is not inserted twice into
+ // ExitBlocks vector.
+ if (current != firstPred)
+ continue;
+
+ // If a terminator has more then two successors, for example
SwitchInst,
+ // then it is possible that there are multiple edges from current
block
+ // to one exit block.
+ if (current->getTerminator()->getNumSuccessors() <= 2) {
+ ExitBlocks.push_back(*I);
+ continue;
+ }
+
+ // In case of multiple edges from current block to exit block, collect
+ // only one edge in ExitBlocks. Use switchExitBlocks to keep track of
+ // duplicate edges.
+ if (std::find(switchExitBlocks.begin(), switchExitBlocks.end(), *I)
+ == switchExitBlocks.end()) {
+ switchExitBlocks.push_back(*I);
+ ExitBlocks.push_back(*I);
+ }
+ }
+ }
+ }
/// getLoopPreheader - If there is a preheader for this loop, return it. A
/// loop has a preheader if there is only one edge to the header of the loop
@@ -133,36 +244,162 @@
///
/// This method returns null if there is no preheader for the loop.
///
- BasicBlock *getLoopPreheader() const;
+ BlockT *getLoopPreheader() const {
+ // Keep track of nodes outside the loop branching to the header...
+ BlockT *Out = 0;
+
+ // Loop over the predecessors of the header node...
+ BlockT *Header = getHeader();
+ for (pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
+ PI != PE; ++PI)
+ if (!contains(*PI)) { // If the block is not in the loop...
+ if (Out && Out != *PI)
+ return 0; // Multiple predecessors outside the loop
+ Out = *PI;
+ }
+
+ // Make sure there is only one exit out of the preheader.
+ assert(Out && "Header of loop has no predecessors from outside loop?");
+ succ_iterator SI = succ_begin(Out);
+ ++SI;
+ if (SI != succ_end(Out))
+ return 0; // Multiple exits from the block, must not be a preheader.
+
+ // If there is exactly one preheader, return it. If there was zero, then
Out
+ // is still null.
+ return Out;
+ }
/// getLoopLatch - If there is a latch block for this loop, return it. A
/// latch block is the canonical backedge for a loop. A loop header in
normal
/// form has two edges into it: one from a preheader and one from a latch
/// block.
- BasicBlock *getLoopLatch() const;
+ BlockT *getLoopLatch() const {
+ BlockT *Header = getHeader();
+ pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
+ if (PI == PE) return 0; // no preds?
+
+ BlockT *Latch = 0;
+ if (contains(*PI))
+ Latch = *PI;
+ ++PI;
+ if (PI == PE) return 0; // only one pred?
+
+ if (contains(*PI)) {
+ if (Latch) return 0; // multiple backedges
+ Latch = *PI;
+ }
+ ++PI;
+ if (PI != PE) return 0; // more than two preds
+
+ return Latch;
+ }
/// getCanonicalInductionVariable - Check to see if the loop has a canonical
/// induction variable: an integer recurrence that starts at 0 and increments
/// by one each time through the loop. If so, return the phi node that
/// corresponds to it.
///
- PHINode *getCanonicalInductionVariable() const;
+ PHINode *getCanonicalInductionVariable() const {
+ BlockT *H = getHeader();
+
+ BlockT *Incoming = 0, *Backedge = 0;
+ pred_iterator PI = pred_begin(H);
+ assert(PI != pred_end(H) && "Loop must have at least one backedge!");
+ Backedge = *PI++;
+ if (PI == pred_end(H)) return 0; // dead loop
+ Incoming = *PI++;
+ if (PI != pred_end(H)) return 0; // multiple backedges?
+
+ if (contains(Incoming)) {
+ if (contains(Backedge))
+ return 0;
+ std::swap(Incoming, Backedge);
+ } else if (!contains(Backedge))
+ return 0;
+
+ // Loop over all of the PHI nodes, looking for a canonical indvar.
+ for (typename BlockT::iterator I = H->begin(); isa<PHINode>(I); ++I) {
+ PHINode *PN = cast<PHINode>(I);
+ if (Instruction *Inc =
+ dyn_cast<Instruction>(PN->getIncomingValueForBlock(Backedge)))
+ if (Inc->getOpcode() == Instruction::Add && Inc->getOperand(0) == PN)
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Inc->getOperand(1)))
+ if (CI->equalsInt(1))
+ return PN;
+ }
+ return 0;
+ }
/// getCanonicalInductionVariableIncrement - Return the LLVM value that holds
/// the canonical induction variable value for the "next" iteration of the
/// loop. This always succeeds if getCanonicalInductionVariable succeeds.
///
- Instruction *getCanonicalInductionVariableIncrement() const;
+ Instruction *getCanonicalInductionVariableIncrement() const {
+ if (PHINode *PN = getCanonicalInductionVariable()) {
+ bool P1InLoop = contains(PN->getIncomingBlock(1));
+ return cast<Instruction>(PN->getIncomingValue(P1InLoop));
+ }
+ return 0;
+ }
/// getTripCount - Return a loop-invariant LLVM value indicating the number
of
/// times the loop will be executed. Note that this means that the backedge
/// of the loop executes N-1 times. If the trip-count cannot be determined,
/// this returns null.
///
- Value *getTripCount() const;
+ Value *getTripCount() const {
+ // Canonical loops will end with a 'cmp ne I, V', where I is the
incremented
+ // canonical induction variable and V is the trip count of the loop.
+ Instruction *Inc = getCanonicalInductionVariableIncrement();
+ if (Inc == 0) return 0;
+ PHINode *IV = cast<PHINode>(Inc->getOperand(0));
+
+ BlockT *BackedgeBlock =
+ IV->getIncomingBlock(contains(IV->getIncomingBlock(1)));
+
+ if (BranchInst *BI = dyn_cast<BranchInst>(BackedgeBlock->getTerminator()))
+ if (BI->isConditional()) {
+ if (ICmpInst *ICI = dyn_cast<ICmpInst>(BI->getCondition())) {
+ if (ICI->getOperand(0) == Inc)
+ if (BI->getSuccessor(0) == getHeader()) {
+ if (ICI->getPredicate() == ICmpInst::ICMP_NE)
+ return ICI->getOperand(1);
+ } else if (ICI->getPredicate() == ICmpInst::ICMP_EQ) {
+ return ICI->getOperand(1);
+ }
+ }
+ }
+
+ return 0;
+ }
/// isLCSSAForm - Return true if the Loop is in LCSSA form
- bool isLCSSAForm() const;
+ bool isLCSSAForm() const {
+ // Sort the blocks vector so that we can use binary search to do quick
+ // lookups.
+ SmallPtrSet<BlockT*, 16> LoopBBs(block_begin(), block_end());
+
+ for (block_iterator BI = block_begin(), E = block_end(); BI != E; ++BI) {
+ BlockT *BB = *BI;
+ for (typename BlockT::iterator I = BB->begin(), E = BB->end(); I != E;
++I)
+ for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI !=
E;
+ ++UI) {
+ BlockT *UserBB = cast<Instruction>(*UI)->getParent();
+ if (PHINode *P = dyn_cast<PHINode>(*UI)) {
+ unsigned OperandNo = UI.getOperandNo();
+ UserBB = P->getIncomingBlock(OperandNo/2);
+ }
+
+ // Check the current block, as a fast-path. Most values are used in
the
+ // same block they are defined in.
+ if (UserBB != BB && !LoopBBs.count(UserBB))
+ return false;
+ }
+ }
+
+ return true;
+ }
//===--------------------------------------------------------------------===//
// APIs for updating loop information after changing the CFG
@@ -174,35 +411,56 @@
/// to the specified LoopInfo object as being in the current basic block. It
/// is not valid to replace the loop header with this method.
///
- void addBasicBlockToLoop(BasicBlock *NewBB, LoopInfo &LI);
+ void addBasicBlockToLoop(BlockT *NewBB, LoopInfo &LI);
/// replaceChildLoopWith - This is used when splitting loops up. It replaces
/// the OldChild entry in our children list with NewChild, and updates the
/// parent pointer of OldChild to be null and the NewChild to be this loop.
/// This updates the loop depth of the new child.
- void replaceChildLoopWith(Loop *OldChild, Loop *NewChild);
+ void replaceChildLoopWith(LoopBase<BlockT> *OldChild,
+ LoopBase<BlockT> *NewChild) {
+ assert(OldChild->ParentLoop == this && "This loop is already broken!");
+ assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
+ typename std::vector<LoopBase<BlockT>*>::iterator I =
+ std::find(SubLoops.begin(), SubLoops.end(),
OldChild);
+ assert(I != SubLoops.end() && "OldChild not in loop!");
+ *I = NewChild;
+ OldChild->ParentLoop = 0;
+ NewChild->ParentLoop = this;
+ }
/// addChildLoop - Add the specified loop to be a child of this loop. This
/// updates the loop depth of the new child.
///
- void addChildLoop(Loop *NewChild);
+ void addChildLoop(LoopBase<BlockT> *NewChild) {
+ assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
+ NewChild->ParentLoop = this;
+ SubLoops.push_back(NewChild);
+ }
/// removeChildLoop - This removes the specified child from being a subloop
of
/// this loop. The loop is not deleted, as it will presumably be inserted
/// into another loop.
- Loop *removeChildLoop(iterator OldChild);
+ LoopBase<BlockT> *removeChildLoop(iterator I) {
+ assert(I != SubLoops.end() && "Cannot remove end iterator!");
+ LoopBase<BlockT> *Child = *I;
+ assert(Child->ParentLoop == this && "Child is not a child of this loop!");
+ SubLoops.erase(SubLoops.begin()+(I-begin()));
+ Child->ParentLoop = 0;
+ return Child;
+ }
/// addBlockEntry - This adds a basic block directly to the basic block list.
/// This should only be used by transformations that create new loops. Other
/// transformations should use addBasicBlockToLoop.
- void addBlockEntry(BasicBlock *BB) {
+ void addBlockEntry(BlockT *BB) {
Blocks.push_back(BB);
}
/// moveToHeader - This method is used to move BB (which must be part of this
/// loop) to be the loop header of the loop (the block that dominates all
/// others).
- void moveToHeader(BasicBlock *BB) {
+ void moveToHeader(BlockT *BB) {
if (Blocks[0] == BB) return;
for (unsigned i = 0; ; ++i) {
assert(i != Blocks.size() && "Loop does not contain BB!");
@@ -217,23 +475,51 @@
/// removeBlockFromLoop - This removes the specified basic block from the
/// current loop, updating the Blocks as appropriate. This does not update
/// the mapping in the LoopInfo class.
- void removeBlockFromLoop(BasicBlock *BB);
+ void removeBlockFromLoop(BlockT *BB) {
+ RemoveFromVector(Blocks, BB);
+ }
/// verifyLoop - Verify loop structure
- void verifyLoop() const;
+ void verifyLoop() const {
+#ifndef NDEBUG
+ assert (getHeader() && "Loop header is missing");
+ assert (getLoopPreheader() && "Loop preheader is missing");
+ assert (getLoopLatch() && "Loop latch is missing");
+ for (typename std::vector<LoopBase<BlockT>*>::const_iterator I =
+ SubLoops.begin(), E = SubLoops.end(); I != E; ++I)
+ (*I)->verifyLoop();
+#endif
+ }
+
+ void print(std::ostream &OS, unsigned Depth = 0) const {
+ OS << std::string(Depth*2, ' ') << "Loop Containing: ";
+
+ for (unsigned i = 0; i < getBlocks().size(); ++i) {
+ if (i) OS << ",";
+ WriteAsOperand(OS, getBlocks()[i], false);
+ }
+ OS << "\n";
- void print(std::ostream &O, unsigned Depth = 0) const;
+ for (iterator I = begin(), E = end(); I != E; ++I)
+ (*I)->print(OS, Depth+2);
+ }
+
void print(std::ostream *O, unsigned Depth = 0) const {
if (O) print(*O, Depth);
}
- void dump() const;
+
+ void dump() const {
+ print(cerr);
+ }
+
private:
friend class LoopInfo;
- Loop(BasicBlock *BB) : ParentLoop(0) {
+ LoopBase(BlockT *BB) : ParentLoop(0) {
Blocks.push_back(BB);
}
};
+typedef LoopBase<BasicBlock> Loop;
//===----------------------------------------------------------------------===//
@@ -244,7 +530,7 @@
// BBMap - Mapping of basic blocks to the inner most loop they occur in
std::map<BasicBlock*, Loop*> BBMap;
std::vector<Loop*> TopLevelLoops;
- friend class Loop;
+ friend class LoopBase<BasicBlock>;
public:
static char ID; // Pass identification, replacement for typeid
@@ -360,6 +646,24 @@
}
};
+template<class BlockT>
+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!");
+
+ // Add the loop mapping to the LoopInfo object...
+ LI.BBMap[NewBB] = this;
+
+ // Add the basic block to this loop and all parent loops...
+ LoopBase<BlockT> *L = this;
+ while (L) {
+ L->Blocks.push_back(NewBB);
+ L = L->getParentLoop();
+ }
+}
+
} // End llvm namespace
// Make sure that any clients of this file link in LoopInfo.cpp
Modified: llvm/trunk/include/llvm/Analysis/LoopPass.h
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/LoopPass.h?rev=44097&r1=44096&r2=44097&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/LoopPass.h (original)
+++ llvm/trunk/include/llvm/Analysis/LoopPass.h Tue Nov 13 20:33:58 2007
@@ -23,7 +23,6 @@
namespace llvm {
class LPPassManager;
-class Loop;
class Function;
class LoopPass : public Pass {
Modified: llvm/trunk/include/llvm/Analysis/ScalarEvolution.h
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/ScalarEvolution.h?rev=44097&r1=44096&r2=44097&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/ScalarEvolution.h (original)
+++ llvm/trunk/include/llvm/Analysis/ScalarEvolution.h Tue Nov 13 20:33:58 2007
@@ -22,6 +22,7 @@
#define LLVM_ANALYSIS_SCALAREVOLUTION_H
#include "llvm/Pass.h"
+#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Streams.h"
#include <set>
@@ -32,8 +33,6 @@
class Instruction;
class Type;
class ConstantRange;
- class Loop;
- class LoopInfo;
class SCEVHandle;
class ScalarEvolution;
Modified: llvm/trunk/include/llvm/Transforms/Utils/Cloning.h
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/Cloning.h?rev=44097&r1=44096&r2=44097&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/Cloning.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/Cloning.h Tue Nov 13 20:33:58 2007
@@ -20,13 +20,12 @@
#include <vector>
#include "llvm/ADT/DenseMap.h"
+#include "llvm/Analysis/LoopInfo.h"
namespace llvm {
class Module;
class Function;
-class Loop;
-class LoopInfo;
class Pass;
class LPPassManager;
class BasicBlock;
Modified: llvm/trunk/include/llvm/Transforms/Utils/FunctionUtils.h
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Utils/FunctionUtils.h?rev=44097&r1=44096&r2=44097&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Transforms/Utils/FunctionUtils.h (original)
+++ llvm/trunk/include/llvm/Transforms/Utils/FunctionUtils.h Tue Nov 13
20:33:58 2007
@@ -14,13 +14,13 @@
#ifndef LLVM_TRANSFORMS_UTILS_FUNCTION_H
#define LLVM_TRANSFORMS_UTILS_FUNCTION_H
-#include <llvm/Analysis/Dominators.h>
+#include "llvm/Analysis/Dominators.h"
+#include "llvm/Analysis/LoopInfo.h"
#include <vector>
namespace llvm {
class BasicBlock;
class Function;
- class Loop;
/// ExtractCodeRegion - rip out a sequence of basic blocks into a new
function
///
Modified: llvm/trunk/lib/Analysis/LoopInfo.cpp
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/LoopInfo.cpp?rev=44097&r1=44096&r2=44097&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/LoopInfo.cpp (original)
+++ llvm/trunk/lib/Analysis/LoopInfo.cpp Tue Nov 13 20:33:58 2007
@@ -34,69 +34,9 @@
//===----------------------------------------------------------------------===//
// Loop implementation
//
-bool Loop::contains(const BasicBlock *BB) const {
- return std::find(Blocks.begin(), Blocks.end(), BB) != Blocks.end();
-}
-
-bool Loop::isLoopExit(const BasicBlock *BB) const {
- for (succ_const_iterator SI = succ_begin(BB), SE = succ_end(BB);
- SI != SE; ++SI) {
- if (!contains(*SI))
- return true;
- }
- return false;
-}
/// getNumBackEdges - Calculate the number of back edges to the loop header.
///
-unsigned Loop::getNumBackEdges() const {
- unsigned NumBackEdges = 0;
- BasicBlock *H = getHeader();
-
- for (pred_iterator I = pred_begin(H), E = pred_end(H); I != E; ++I)
- if (contains(*I))
- ++NumBackEdges;
-
- return NumBackEdges;
-}
-
-/// isLoopInvariant - Return true if the specified value is loop invariant
-///
-bool Loop::isLoopInvariant(Value *V) const {
- if (Instruction *I = dyn_cast<Instruction>(V))
- return !contains(I->getParent());
- return true; // All non-instructions are loop invariant
-}
-
-void Loop::print(std::ostream &OS, unsigned Depth) const {
- OS << std::string(Depth*2, ' ') << "Loop Containing: ";
-
- for (unsigned i = 0; i < getBlocks().size(); ++i) {
- if (i) OS << ",";
- WriteAsOperand(OS, getBlocks()[i], false);
- }
- OS << "\n";
-
- for (iterator I = begin(), E = end(); I != E; ++I)
- (*I)->print(OS, Depth+2);
-}
-
-/// verifyLoop - Verify loop structure
-void Loop::verifyLoop() const {
-#ifndef NDEBUG
- assert (getHeader() && "Loop header is missing");
- assert (getLoopPreheader() && "Loop preheader is missing");
- assert (getLoopLatch() && "Loop latch is missing");
- for (std::vector<Loop*>::const_iterator I = SubLoops.begin(), E =
SubLoops.end();
- I != E; ++I)
- (*I)->verifyLoop();
-#endif
-}
-
-void Loop::dump() const {
- print(cerr);
-}
-
//===----------------------------------------------------------------------===//
// LoopInfo implementation
@@ -341,341 +281,5 @@
}
}
-
-//===----------------------------------------------------------------------===//
-// APIs for simple analysis of the loop.
-//
-
-/// getExitingBlocks - Return all blocks inside the loop that have successors
-/// outside of the loop. These are the blocks _inside of the current loop_
-/// which branch out. The returned list is always unique.
-///
-void Loop::getExitingBlocks(SmallVectorImpl<BasicBlock*> &ExitingBlocks) const
{
- // Sort the blocks vector so that we can use binary search to do quick
- // lookups.
- SmallVector<BasicBlock*, 128> LoopBBs(block_begin(), block_end());
- std::sort(LoopBBs.begin(), LoopBBs.end());
-
- for (std::vector<BasicBlock*>::const_iterator BI = Blocks.begin(),
- BE = Blocks.end(); BI != BE; ++BI)
- for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I)
- if (!std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I)) {
- // Not in current loop? It must be an exit block.
- ExitingBlocks.push_back(*BI);
- break;
- }
-}
-
-/// getExitBlocks - Return all of the successor blocks of this loop. These
-/// are the blocks _outside of the current loop_ which are branched to.
-///
-void Loop::getExitBlocks(SmallVectorImpl<BasicBlock*> &ExitBlocks) const {
- // Sort the blocks vector so that we can use binary search to do quick
- // lookups.
- SmallVector<BasicBlock*, 128> LoopBBs(block_begin(), block_end());
- std::sort(LoopBBs.begin(), LoopBBs.end());
-
- for (std::vector<BasicBlock*>::const_iterator BI = Blocks.begin(),
- BE = Blocks.end(); BI != BE; ++BI)
- for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I)
- if (!std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I))
- // Not in current loop? It must be an exit block.
- ExitBlocks.push_back(*I);
-}
-
-/// getUniqueExitBlocks - Return all unique successor blocks of this loop.
These
-/// are the blocks _outside of the current loop_ which are branched to. This
-/// assumes that loop is in canonical form.
-//
-void Loop::getUniqueExitBlocks(SmallVectorImpl<BasicBlock*> &ExitBlocks) const
{
- // Sort the blocks vector so that we can use binary search to do quick
- // lookups.
- SmallVector<BasicBlock*, 128> LoopBBs(block_begin(), block_end());
- std::sort(LoopBBs.begin(), LoopBBs.end());
-
- std::vector<BasicBlock*> switchExitBlocks;
-
- for (std::vector<BasicBlock*>::const_iterator BI = Blocks.begin(),
- BE = Blocks.end(); BI != BE; ++BI) {
-
- BasicBlock *current = *BI;
- switchExitBlocks.clear();
-
- for (succ_iterator I = succ_begin(*BI), E = succ_end(*BI); I != E; ++I) {
- if (std::binary_search(LoopBBs.begin(), LoopBBs.end(), *I))
- // If block is inside the loop then it is not a exit block.
- continue;
-
- pred_iterator PI = pred_begin(*I);
- BasicBlock *firstPred = *PI;
-
- // If current basic block is this exit block's first predecessor
- // then only insert exit block in to the output ExitBlocks vector.
- // This ensures that same exit block is not inserted twice into
- // ExitBlocks vector.
- if (current != firstPred)
- continue;
-
- // If a terminator has more then two successors, for example SwitchInst,
- // then it is possible that there are multiple edges from current block
- // to one exit block.
- if (current->getTerminator()->getNumSuccessors() <= 2) {
- ExitBlocks.push_back(*I);
- continue;
- }
-
- // In case of multiple edges from current block to exit block, collect
- // only one edge in ExitBlocks. Use switchExitBlocks to keep track of
- // duplicate edges.
- if (std::find(switchExitBlocks.begin(), switchExitBlocks.end(), *I)
- == switchExitBlocks.end()) {
- switchExitBlocks.push_back(*I);
- ExitBlocks.push_back(*I);
- }
- }
- }
-}
-
-
-/// getLoopPreheader - If there is a preheader for this loop, return it. A
-/// loop has a preheader if there is only one edge to the header of the loop
-/// from outside of the loop. If this is the case, the block branching to the
-/// header of the loop is the preheader node.
-///
-/// This method returns null if there is no preheader for the loop.
-///
-BasicBlock *Loop::getLoopPreheader() const {
- // Keep track of nodes outside the loop branching to the header...
- BasicBlock *Out = 0;
-
- // Loop over the predecessors of the header node...
- BasicBlock *Header = getHeader();
- for (pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
- PI != PE; ++PI)
- if (!contains(*PI)) { // If the block is not in the loop...
- if (Out && Out != *PI)
- return 0; // Multiple predecessors outside the loop
- Out = *PI;
- }
-
- // Make sure there is only one exit out of the preheader.
- assert(Out && "Header of loop has no predecessors from outside loop?");
- succ_iterator SI = succ_begin(Out);
- ++SI;
- if (SI != succ_end(Out))
- return 0; // Multiple exits from the block, must not be a preheader.
-
- // If there is exactly one preheader, return it. If there was zero, then Out
- // is still null.
- return Out;
-}
-
-/// getLoopLatch - If there is a latch block for this loop, return it. A
-/// latch block is the canonical backedge for a loop. A loop header in normal
-/// form has two edges into it: one from a preheader and one from a latch
-/// block.
-BasicBlock *Loop::getLoopLatch() const {
- BasicBlock *Header = getHeader();
- pred_iterator PI = pred_begin(Header), PE = pred_end(Header);
- if (PI == PE) return 0; // no preds?
-
- BasicBlock *Latch = 0;
- if (contains(*PI))
- Latch = *PI;
- ++PI;
- if (PI == PE) return 0; // only one pred?
-
- if (contains(*PI)) {
- if (Latch) return 0; // multiple backedges
- Latch = *PI;
- }
- ++PI;
- if (PI != PE) return 0; // more than two preds
-
- return Latch;
-}
-
-/// getCanonicalInductionVariable - Check to see if the loop has a canonical
-/// induction variable: an integer recurrence that starts at 0 and increments
by
-/// one each time through the loop. If so, return the phi node that
corresponds
-/// to it.
-///
-PHINode *Loop::getCanonicalInductionVariable() const {
- BasicBlock *H = getHeader();
-
- BasicBlock *Incoming = 0, *Backedge = 0;
- pred_iterator PI = pred_begin(H);
- assert(PI != pred_end(H) && "Loop must have at least one backedge!");
- Backedge = *PI++;
- if (PI == pred_end(H)) return 0; // dead loop
- Incoming = *PI++;
- if (PI != pred_end(H)) return 0; // multiple backedges?
-
- if (contains(Incoming)) {
- if (contains(Backedge))
- return 0;
- std::swap(Incoming, Backedge);
- } else if (!contains(Backedge))
- return 0;
-
- // Loop over all of the PHI nodes, looking for a canonical indvar.
- for (BasicBlock::iterator I = H->begin(); isa<PHINode>(I); ++I) {
- PHINode *PN = cast<PHINode>(I);
- if (Instruction *Inc =
- dyn_cast<Instruction>(PN->getIncomingValueForBlock(Backedge)))
- if (Inc->getOpcode() == Instruction::Add && Inc->getOperand(0) == PN)
- if (ConstantInt *CI = dyn_cast<ConstantInt>(Inc->getOperand(1)))
- if (CI->equalsInt(1))
- return PN;
- }
- return 0;
-}
-
-/// getCanonicalInductionVariableIncrement - Return the LLVM value that holds
-/// the canonical induction variable value for the "next" iteration of the
loop.
-/// This always succeeds if getCanonicalInductionVariable succeeds.
-///
-Instruction *Loop::getCanonicalInductionVariableIncrement() const {
- if (PHINode *PN = getCanonicalInductionVariable()) {
- bool P1InLoop = contains(PN->getIncomingBlock(1));
- return cast<Instruction>(PN->getIncomingValue(P1InLoop));
- }
- return 0;
-}
-
-/// getTripCount - Return a loop-invariant LLVM value indicating the number of
-/// times the loop will be executed. Note that this means that the backedge of
-/// the loop executes N-1 times. If the trip-count cannot be determined, this
-/// returns null.
-///
-Value *Loop::getTripCount() const {
- // Canonical loops will end with a 'cmp ne I, V', where I is the incremented
- // canonical induction variable and V is the trip count of the loop.
- Instruction *Inc = getCanonicalInductionVariableIncrement();
- if (Inc == 0) return 0;
- PHINode *IV = cast<PHINode>(Inc->getOperand(0));
-
- BasicBlock *BackedgeBlock =
- IV->getIncomingBlock(contains(IV->getIncomingBlock(1)));
-
- if (BranchInst *BI = dyn_cast<BranchInst>(BackedgeBlock->getTerminator()))
- if (BI->isConditional()) {
- if (ICmpInst *ICI = dyn_cast<ICmpInst>(BI->getCondition())) {
- if (ICI->getOperand(0) == Inc)
- if (BI->getSuccessor(0) == getHeader()) {
- if (ICI->getPredicate() == ICmpInst::ICMP_NE)
- return ICI->getOperand(1);
- } else if (ICI->getPredicate() == ICmpInst::ICMP_EQ) {
- return ICI->getOperand(1);
- }
- }
- }
-
- return 0;
-}
-
-/// isLCSSAForm - Return true if the Loop is in LCSSA form
-bool Loop::isLCSSAForm() const {
- // Sort the blocks vector so that we can use binary search to do quick
- // lookups.
- SmallPtrSet<BasicBlock*, 16> LoopBBs(block_begin(), block_end());
-
- for (block_iterator BI = block_begin(), E = block_end(); BI != E; ++BI) {
- BasicBlock *BB = *BI;
- for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
- for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E;
- ++UI) {
- BasicBlock *UserBB = cast<Instruction>(*UI)->getParent();
- if (PHINode *P = dyn_cast<PHINode>(*UI)) {
- unsigned OperandNo = UI.getOperandNo();
- UserBB = P->getIncomingBlock(OperandNo/2);
- }
-
- // Check the current block, as a fast-path. Most values are used in
the
- // same block they are defined in.
- if (UserBB != BB && !LoopBBs.count(UserBB))
- return false;
- }
- }
-
- return true;
-}
-
-//===-------------------------------------------------------------------===//
-// APIs for updating loop information after changing the CFG
-//
-
-/// addBasicBlockToLoop - This function is used by other analyses to update
loop
-/// information. NewBB is set to be a new member of the current loop. Because
-/// of this, it is added as a member of all parent loops, and is added to the
-/// specified LoopInfo object as being in the current basic block. It is not
-/// valid to replace the loop header with this method.
-///
-void Loop::addBasicBlockToLoop(BasicBlock *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!");
-
- // Add the loop mapping to the LoopInfo object...
- LI.BBMap[NewBB] = this;
-
- // Add the basic block to this loop and all parent loops...
- Loop *L = this;
- while (L) {
- L->Blocks.push_back(NewBB);
- L = L->getParentLoop();
- }
-}
-
-/// replaceChildLoopWith - This is used when splitting loops up. It replaces
-/// the OldChild entry in our children list with NewChild, and updates the
-/// parent pointers of the two loops as appropriate.
-void Loop::replaceChildLoopWith(Loop *OldChild, Loop *NewChild) {
- assert(OldChild->ParentLoop == this && "This loop is already broken!");
- assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
- std::vector<Loop*>::iterator I = std::find(SubLoops.begin(), SubLoops.end(),
- OldChild);
- assert(I != SubLoops.end() && "OldChild not in loop!");
- *I = NewChild;
- OldChild->ParentLoop = 0;
- NewChild->ParentLoop = this;
-}
-
-/// addChildLoop - Add the specified loop to be a child of this loop.
-///
-void Loop::addChildLoop(Loop *NewChild) {
- assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
- NewChild->ParentLoop = this;
- SubLoops.push_back(NewChild);
-}
-
-template<typename T>
-static void RemoveFromVector(std::vector<T*> &V, T *N) {
- typename std::vector<T*>::iterator I = std::find(V.begin(), V.end(), N);
- assert(I != V.end() && "N is not in this list!");
- V.erase(I);
-}
-
-/// removeChildLoop - This removes the specified child from being a subloop of
-/// this loop. The loop is not deleted, as it will presumably be inserted
-/// into another loop.
-Loop *Loop::removeChildLoop(iterator I) {
- assert(I != SubLoops.end() && "Cannot remove end iterator!");
- Loop *Child = *I;
- assert(Child->ParentLoop == this && "Child is not a child of this loop!");
- SubLoops.erase(SubLoops.begin()+(I-begin()));
- Child->ParentLoop = 0;
- return Child;
-}
-
-
-/// removeBlockFromLoop - This removes the specified basic block from the
-/// current loop, updating the Blocks and ExitBlocks lists as appropriate.
This
-/// does not update the mapping in the LoopInfo class.
-void Loop::removeBlockFromLoop(BasicBlock *BB) {
- RemoveFromVector(Blocks, BB);
-}
-
// Ensure this file gets linked when LoopInfo.h is used.
DEFINING_FILE_FOR(LoopInfo)
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