#ifndef LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
#define LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
-#include "llvm/CodeGen/MachineBasicBlock.h"
-#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/ADT/BitVector.h"
-#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/IndexedMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/SlotIndexes.h"
#include "llvm/Support/Allocator.h"
+#include "llvm/Target/TargetRegisterInfo.h"
#include <cmath>
+#include <iterator>
namespace llvm {
class AliasAnalysis;
+ class LiveRangeCalc;
class LiveVariables;
+ class MachineDominatorTree;
class MachineLoopInfo;
class TargetRegisterInfo;
class MachineRegisterInfo;
class TargetInstrInfo;
class TargetRegisterClass;
class VirtRegMap;
- typedef std::pair<MachineInstrIndex, MachineBasicBlock*> IdxMBBPair;
-
- inline bool operator<(MachineInstrIndex V, const IdxMBBPair &IM) {
- return V < IM.first;
- }
-
- inline bool operator<(const IdxMBBPair &IM, MachineInstrIndex V) {
- return IM.first < V;
- }
- struct Idx2MBBCompare {
- bool operator()(const IdxMBBPair &LHS, const IdxMBBPair &RHS) const {
- return LHS.first < RHS.first;
- }
- };
-
class LiveIntervals : public MachineFunctionPass {
- MachineFunction* mf_;
- MachineRegisterInfo* mri_;
- const TargetMachine* tm_;
- const TargetRegisterInfo* tri_;
- const TargetInstrInfo* tii_;
- AliasAnalysis *aa_;
- LiveVariables* lv_;
+ MachineFunction* MF;
+ MachineRegisterInfo* MRI;
+ const TargetMachine* TM;
+ const TargetRegisterInfo* TRI;
+ const TargetInstrInfo* TII;
+ AliasAnalysis *AA;
+ LiveVariables* LV;
+ SlotIndexes* Indexes;
+ MachineDominatorTree *DomTree;
+ LiveRangeCalc *LRCalc;
/// Special pool allocator for VNInfo's (LiveInterval val#).
///
- BumpPtrAllocator VNInfoAllocator;
+ VNInfo::Allocator VNInfoAllocator;
- /// MBB2IdxMap - The indexes of the first and last instructions in the
- /// specified basic block.
- std::vector<std::pair<MachineInstrIndex, MachineInstrIndex> > MBB2IdxMap;
+ /// Live interval pointers for all the virtual registers.
+ IndexedMap<LiveInterval*, VirtReg2IndexFunctor> VirtRegIntervals;
- /// Idx2MBBMap - Sorted list of pairs of index of first instruction
- /// and MBB id.
- std::vector<IdxMBBPair> Idx2MBBMap;
+ /// RegMaskSlots - Sorted list of instructions with register mask operands.
+ /// Always use the 'r' slot, RegMasks are normal clobbers, not early
+ /// clobbers.
+ SmallVector<SlotIndex, 8> RegMaskSlots;
- /// FunctionSize - The number of instructions present in the function
- uint64_t FunctionSize;
-
- typedef DenseMap<const MachineInstr*, MachineInstrIndex> Mi2IndexMap;
- Mi2IndexMap mi2iMap_;
-
- typedef std::vector<MachineInstr*> Index2MiMap;
- Index2MiMap i2miMap_;
-
- typedef DenseMap<unsigned, LiveInterval*> Reg2IntervalMap;
- Reg2IntervalMap r2iMap_;
-
- DenseMap<MachineBasicBlock*, MachineInstrIndex> terminatorGaps;
-
- /// phiJoinCopies - Copy instructions which are PHI joins.
- SmallVector<MachineInstr*, 16> phiJoinCopies;
-
- /// allocatableRegs_ - A bit vector of allocatable registers.
- BitVector allocatableRegs_;
-
- /// CloneMIs - A list of clones as result of re-materialization.
- std::vector<MachineInstr*> CloneMIs;
-
- typedef LiveInterval::InstrSlots InstrSlots;
+ /// RegMaskBits - This vector is parallel to RegMaskSlots, it holds a
+ /// pointer to the corresponding register mask. This pointer can be
+ /// recomputed as:
+ ///
+ /// MI = Indexes->getInstructionFromIndex(RegMaskSlot[N]);
+ /// unsigned OpNum = findRegMaskOperand(MI);
+ /// RegMaskBits[N] = MI->getOperand(OpNum).getRegMask();
+ ///
+ /// This is kept in a separate vector partly because some standard
+ /// libraries don't support lower_bound() with mixed objects, partly to
+ /// improve locality when searching in RegMaskSlots.
+ /// Also see the comment in LiveInterval::find().
+ SmallVector<const uint32_t*, 8> RegMaskBits;
+
+ /// For each basic block number, keep (begin, size) pairs indexing into the
+ /// RegMaskSlots and RegMaskBits arrays.
+ /// Note that basic block numbers may not be layout contiguous, that's why
+ /// we can't just keep track of the first register mask in each basic
+ /// block.
+ SmallVector<std::pair<unsigned, unsigned>, 8> RegMaskBlocks;
+
+ /// RegUnitIntervals - Keep a live interval for each register unit as a way
+ /// of tracking fixed physreg interference.
+ SmallVector<LiveInterval*, 0> RegUnitIntervals;
public:
static char ID; // Pass identification, replacement for typeid
- LiveIntervals() : MachineFunctionPass(&ID) {}
+ LiveIntervals();
+ virtual ~LiveIntervals();
- MachineInstrIndex getBaseIndex(MachineInstrIndex index) {
- return MachineInstrIndex(index, MachineInstrIndex::LOAD);
- }
- MachineInstrIndex getBoundaryIndex(MachineInstrIndex index) {
- return MachineInstrIndex(index,
- (MachineInstrIndex::Slot)(MachineInstrIndex::NUM - 1));
- }
- MachineInstrIndex getLoadIndex(MachineInstrIndex index) {
- return MachineInstrIndex(index, MachineInstrIndex::LOAD);
- }
- MachineInstrIndex getUseIndex(MachineInstrIndex index) {
- return MachineInstrIndex(index, MachineInstrIndex::USE);
- }
- MachineInstrIndex getDefIndex(MachineInstrIndex index) {
- return MachineInstrIndex(index, MachineInstrIndex::DEF);
- }
- MachineInstrIndex getStoreIndex(MachineInstrIndex index) {
- return MachineInstrIndex(index, MachineInstrIndex::STORE);
- }
+ // Calculate the spill weight to assign to a single instruction.
+ static float getSpillWeight(bool isDef, bool isUse, unsigned loopDepth);
- MachineInstrIndex getNextSlot(MachineInstrIndex m) const {
- return m.nextSlot_();
+ LiveInterval &getInterval(unsigned Reg) {
+ LiveInterval *LI = VirtRegIntervals[Reg];
+ assert(LI && "Interval does not exist for virtual register");
+ return *LI;
}
- MachineInstrIndex getNextIndex(MachineInstrIndex m) const {
- return m.nextIndex_();
+ const LiveInterval &getInterval(unsigned Reg) const {
+ return const_cast<LiveIntervals*>(this)->getInterval(Reg);
}
- MachineInstrIndex getPrevSlot(MachineInstrIndex m) const {
- return m.prevSlot_();
+ bool hasInterval(unsigned Reg) const {
+ return VirtRegIntervals.inBounds(Reg) && VirtRegIntervals[Reg];
}
- MachineInstrIndex getPrevIndex(MachineInstrIndex m) const {
- return m.prevIndex_();
- }
-
- static float getSpillWeight(bool isDef, bool isUse, unsigned loopDepth) {
- return (isDef + isUse) * powf(10.0F, (float)loopDepth);
- }
-
- typedef Reg2IntervalMap::iterator iterator;
- typedef Reg2IntervalMap::const_iterator const_iterator;
- const_iterator begin() const { return r2iMap_.begin(); }
- const_iterator end() const { return r2iMap_.end(); }
- iterator begin() { return r2iMap_.begin(); }
- iterator end() { return r2iMap_.end(); }
- unsigned getNumIntervals() const { return (unsigned)r2iMap_.size(); }
-
- LiveInterval &getInterval(unsigned reg) {
- Reg2IntervalMap::iterator I = r2iMap_.find(reg);
- assert(I != r2iMap_.end() && "Interval does not exist for register");
- return *I->second;
+ // Interval creation.
+ LiveInterval &getOrCreateInterval(unsigned Reg) {
+ if (!hasInterval(Reg)) {
+ VirtRegIntervals.grow(Reg);
+ VirtRegIntervals[Reg] = createInterval(Reg);
+ }
+ return getInterval(Reg);
}
- const LiveInterval &getInterval(unsigned reg) const {
- Reg2IntervalMap::const_iterator I = r2iMap_.find(reg);
- assert(I != r2iMap_.end() && "Interval does not exist for register");
- return *I->second;
+ // Interval removal.
+ void removeInterval(unsigned Reg) {
+ delete VirtRegIntervals[Reg];
+ VirtRegIntervals[Reg] = 0;
}
- bool hasInterval(unsigned reg) const {
- return r2iMap_.count(reg);
- }
+ /// addLiveRangeToEndOfBlock - Given a register and an instruction,
+ /// adds a live range from that instruction to the end of its MBB.
+ LiveRange addLiveRangeToEndOfBlock(unsigned reg,
+ MachineInstr* startInst);
- /// getMBBStartIdx - Return the base index of the first instruction in the
- /// specified MachineBasicBlock.
- MachineInstrIndex getMBBStartIdx(MachineBasicBlock *MBB) const {
- return getMBBStartIdx(MBB->getNumber());
- }
- MachineInstrIndex getMBBStartIdx(unsigned MBBNo) const {
- assert(MBBNo < MBB2IdxMap.size() && "Invalid MBB number!");
- return MBB2IdxMap[MBBNo].first;
- }
+ /// shrinkToUses - After removing some uses of a register, shrink its live
+ /// range to just the remaining uses. This method does not compute reaching
+ /// defs for new uses, and it doesn't remove dead defs.
+ /// Dead PHIDef values are marked as unused.
+ /// New dead machine instructions are added to the dead vector.
+ /// Return true if the interval may have been separated into multiple
+ /// connected components.
+ bool shrinkToUses(LiveInterval *li,
+ SmallVectorImpl<MachineInstr*> *dead = 0);
+
+ /// extendToIndices - Extend the live range of LI to reach all points in
+ /// Indices. The points in the Indices array must be jointly dominated by
+ /// existing defs in LI. PHI-defs are added as needed to maintain SSA form.
+ ///
+ /// If a SlotIndex in Indices is the end index of a basic block, LI will be
+ /// extended to be live out of the basic block.
+ ///
+ /// See also LiveRangeCalc::extend().
+ void extendToIndices(LiveInterval *LI, ArrayRef<SlotIndex> Indices);
- /// getMBBEndIdx - Return the store index of the last instruction in the
- /// specified MachineBasicBlock.
- MachineInstrIndex getMBBEndIdx(MachineBasicBlock *MBB) const {
- return getMBBEndIdx(MBB->getNumber());
- }
- MachineInstrIndex getMBBEndIdx(unsigned MBBNo) const {
- assert(MBBNo < MBB2IdxMap.size() && "Invalid MBB number!");
- return MBB2IdxMap[MBBNo].second;
- }
+ /// pruneValue - If an LI value is live at Kill, prune its live range by
+ /// removing any liveness reachable from Kill. Add live range end points to
+ /// EndPoints such that extendToIndices(LI, EndPoints) will reconstruct the
+ /// value's live range.
+ ///
+ /// Calling pruneValue() and extendToIndices() can be used to reconstruct
+ /// SSA form after adding defs to a virtual register.
+ void pruneValue(LiveInterval *LI, SlotIndex Kill,
+ SmallVectorImpl<SlotIndex> *EndPoints);
- /// getScaledIntervalSize - get the size of an interval in "units,"
- /// where every function is composed of one thousand units. This
- /// measure scales properly with empty index slots in the function.
- double getScaledIntervalSize(LiveInterval& I) {
- return (1000.0 / InstrSlots::NUM * I.getSize()) / i2miMap_.size();
- }
-
- /// getApproximateInstructionCount - computes an estimate of the number
- /// of instructions in a given LiveInterval.
- unsigned getApproximateInstructionCount(LiveInterval& I) {
- double IntervalPercentage = getScaledIntervalSize(I) / 1000.0;
- return (unsigned)(IntervalPercentage * FunctionSize);
+ SlotIndexes *getSlotIndexes() const {
+ return Indexes;
}
- /// getMBBFromIndex - given an index in any instruction of an
- /// MBB return a pointer the MBB
- MachineBasicBlock* getMBBFromIndex(MachineInstrIndex index) const {
- std::vector<IdxMBBPair>::const_iterator I =
- std::lower_bound(Idx2MBBMap.begin(), Idx2MBBMap.end(), index);
- // Take the pair containing the index
- std::vector<IdxMBBPair>::const_iterator J =
- ((I != Idx2MBBMap.end() && I->first > index) ||
- (I == Idx2MBBMap.end() && Idx2MBBMap.size()>0)) ? (I-1): I;
-
- assert(J != Idx2MBBMap.end() && J->first <= index &&
- index <= getMBBEndIdx(J->second) &&
- "index does not correspond to an MBB");
- return J->second;
+ AliasAnalysis *getAliasAnalysis() const {
+ return AA;
}
- /// getInstructionIndex - returns the base index of instr
- MachineInstrIndex getInstructionIndex(const MachineInstr* instr) const {
- Mi2IndexMap::const_iterator it = mi2iMap_.find(instr);
- assert(it != mi2iMap_.end() && "Invalid instruction!");
- return it->second;
+ /// isNotInMIMap - returns true if the specified machine instr has been
+ /// removed or was never entered in the map.
+ bool isNotInMIMap(const MachineInstr* Instr) const {
+ return !Indexes->hasIndex(Instr);
}
- /// getInstructionFromIndex - given an index in any slot of an
- /// instruction return a pointer the instruction
- MachineInstr* getInstructionFromIndex(MachineInstrIndex index) const {
- // convert index to vector index
- unsigned i = index.getVecIndex();
- assert(i < i2miMap_.size() &&
- "index does not correspond to an instruction");
- return i2miMap_[i];
+ /// Returns the base index of the given instruction.
+ SlotIndex getInstructionIndex(const MachineInstr *instr) const {
+ return Indexes->getInstructionIndex(instr);
}
- /// hasGapBeforeInstr - Return true if the previous instruction slot,
- /// i.e. Index - InstrSlots::NUM, is not occupied.
- bool hasGapBeforeInstr(MachineInstrIndex Index) {
- Index = getBaseIndex(getPrevIndex(Index));
- return getInstructionFromIndex(Index) == 0;
+ /// Returns the instruction associated with the given index.
+ MachineInstr* getInstructionFromIndex(SlotIndex index) const {
+ return Indexes->getInstructionFromIndex(index);
}
- /// hasGapAfterInstr - Return true if the successive instruction slot,
- /// i.e. Index + InstrSlots::Num, is not occupied.
- bool hasGapAfterInstr(MachineInstrIndex Index) {
- Index = getBaseIndex(getNextIndex(Index));
- return getInstructionFromIndex(Index) == 0;
+ /// Return the first index in the given basic block.
+ SlotIndex getMBBStartIdx(const MachineBasicBlock *mbb) const {
+ return Indexes->getMBBStartIdx(mbb);
}
- /// findGapBeforeInstr - Find an empty instruction slot before the
- /// specified index. If "Furthest" is true, find one that's furthest
- /// away from the index (but before any index that's occupied).
- MachineInstrIndex findGapBeforeInstr(MachineInstrIndex Index,
- bool Furthest = false) {
- Index = getBaseIndex(getPrevIndex(Index));
- if (getInstructionFromIndex(Index))
- return MachineInstrIndex(); // No gap!
- if (!Furthest)
- return Index;
- MachineInstrIndex PrevIndex = getBaseIndex(getPrevIndex(Index));
- while (getInstructionFromIndex(Index)) {
- Index = PrevIndex;
- PrevIndex = getBaseIndex(getPrevIndex(Index));
- }
- return Index;
+ /// Return the last index in the given basic block.
+ SlotIndex getMBBEndIdx(const MachineBasicBlock *mbb) const {
+ return Indexes->getMBBEndIdx(mbb);
}
- /// InsertMachineInstrInMaps - Insert the specified machine instruction
- /// into the instruction index map at the given index.
- void InsertMachineInstrInMaps(MachineInstr *MI, MachineInstrIndex Index) {
- i2miMap_[Index.getVecIndex()] = MI;
- Mi2IndexMap::iterator it = mi2iMap_.find(MI);
- assert(it == mi2iMap_.end() && "Already in map!");
- mi2iMap_[MI] = Index;
+ bool isLiveInToMBB(const LiveInterval &li,
+ const MachineBasicBlock *mbb) const {
+ return li.liveAt(getMBBStartIdx(mbb));
}
- /// conflictsWithPhysRegDef - Returns true if the specified register
- /// is defined during the duration of the specified interval.
- bool conflictsWithPhysRegDef(const LiveInterval &li, VirtRegMap &vrm,
- unsigned reg);
-
- /// conflictsWithPhysRegRef - Similar to conflictsWithPhysRegRef except
- /// it can check use as well.
- bool conflictsWithPhysRegRef(LiveInterval &li, unsigned Reg,
- bool CheckUse,
- SmallPtrSet<MachineInstr*,32> &JoinedCopies);
-
- /// findLiveInMBBs - Given a live range, if the value of the range
- /// is live in any MBB returns true as well as the list of basic blocks
- /// in which the value is live.
- bool findLiveInMBBs(MachineInstrIndex Start, MachineInstrIndex End,
- SmallVectorImpl<MachineBasicBlock*> &MBBs) const;
-
- /// findReachableMBBs - Return a list MBB that can be reached via any
- /// branch or fallthroughs. Return true if the list is not empty.
- bool findReachableMBBs(MachineInstrIndex Start, MachineInstrIndex End,
- SmallVectorImpl<MachineBasicBlock*> &MBBs) const;
-
- // Interval creation
-
- LiveInterval &getOrCreateInterval(unsigned reg) {
- Reg2IntervalMap::iterator I = r2iMap_.find(reg);
- if (I == r2iMap_.end())
- I = r2iMap_.insert(std::make_pair(reg, createInterval(reg))).first;
- return *I->second;
+ bool isLiveOutOfMBB(const LiveInterval &li,
+ const MachineBasicBlock *mbb) const {
+ return li.liveAt(getMBBEndIdx(mbb).getPrevSlot());
}
- /// dupInterval - Duplicate a live interval. The caller is responsible for
- /// managing the allocated memory.
- LiveInterval *dupInterval(LiveInterval *li);
-
- /// addLiveRangeToEndOfBlock - Given a register and an instruction,
- /// adds a live range from that instruction to the end of its MBB.
- LiveRange addLiveRangeToEndOfBlock(unsigned reg,
- MachineInstr* startInst);
-
- // Interval removal
-
- void removeInterval(unsigned Reg) {
- DenseMap<unsigned, LiveInterval*>::iterator I = r2iMap_.find(Reg);
- delete I->second;
- r2iMap_.erase(I);
+ MachineBasicBlock* getMBBFromIndex(SlotIndex index) const {
+ return Indexes->getMBBFromIndex(index);
}
- /// isNotInMIMap - returns true if the specified machine instr has been
- /// removed or was never entered in the map.
- bool isNotInMIMap(MachineInstr* instr) const {
- return !mi2iMap_.count(instr);
+ SlotIndex InsertMachineInstrInMaps(MachineInstr *MI) {
+ return Indexes->insertMachineInstrInMaps(MI);
}
- /// RemoveMachineInstrFromMaps - This marks the specified machine instr as
- /// deleted.
void RemoveMachineInstrFromMaps(MachineInstr *MI) {
- // remove index -> MachineInstr and
- // MachineInstr -> index mappings
- Mi2IndexMap::iterator mi2i = mi2iMap_.find(MI);
- if (mi2i != mi2iMap_.end()) {
- i2miMap_[mi2i->second.index/InstrSlots::NUM] = 0;
- mi2iMap_.erase(mi2i);
- }
+ Indexes->removeMachineInstrFromMaps(MI);
}
- /// ReplaceMachineInstrInMaps - Replacing a machine instr with a new one in
- /// maps used by register allocator.
void ReplaceMachineInstrInMaps(MachineInstr *MI, MachineInstr *NewMI) {
- Mi2IndexMap::iterator mi2i = mi2iMap_.find(MI);
- if (mi2i == mi2iMap_.end())
- return;
- i2miMap_[mi2i->second.index/InstrSlots::NUM] = NewMI;
- Mi2IndexMap::iterator it = mi2iMap_.find(MI);
- assert(it != mi2iMap_.end() && "Invalid instruction!");
- MachineInstrIndex Index = it->second;
- mi2iMap_.erase(it);
- mi2iMap_[NewMI] = Index;
+ Indexes->replaceMachineInstrInMaps(MI, NewMI);
}
- BumpPtrAllocator& getVNInfoAllocator() { return VNInfoAllocator; }
+ bool findLiveInMBBs(SlotIndex Start, SlotIndex End,
+ SmallVectorImpl<MachineBasicBlock*> &MBBs) const {
+ return Indexes->findLiveInMBBs(Start, End, MBBs);
+ }
- /// getVNInfoSourceReg - Helper function that parses the specified VNInfo
- /// copy field and returns the source register that defines it.
- unsigned getVNInfoSourceReg(const VNInfo *VNI) const;
+ VNInfo::Allocator& getVNInfoAllocator() { return VNInfoAllocator; }
virtual void getAnalysisUsage(AnalysisUsage &AU) const;
virtual void releaseMemory();
/// print - Implement the dump method.
virtual void print(raw_ostream &O, const Module* = 0) const;
- /// addIntervalsForSpills - Create new intervals for spilled defs / uses of
- /// the given interval. FIXME: It also returns the weight of the spill slot
- /// (if any is created) by reference. This is temporary.
- std::vector<LiveInterval*>
- addIntervalsForSpills(const LiveInterval& i,
- SmallVectorImpl<LiveInterval*> &SpillIs,
- const MachineLoopInfo *loopInfo, VirtRegMap& vrm);
-
- /// addIntervalsForSpillsFast - Quickly create new intervals for spilled
- /// defs / uses without remat or splitting.
- std::vector<LiveInterval*>
- addIntervalsForSpillsFast(const LiveInterval &li,
- const MachineLoopInfo *loopInfo, VirtRegMap &vrm);
-
- /// spillPhysRegAroundRegDefsUses - Spill the specified physical register
- /// around all defs and uses of the specified interval. Return true if it
- /// was able to cut its interval.
- bool spillPhysRegAroundRegDefsUses(const LiveInterval &li,
- unsigned PhysReg, VirtRegMap &vrm);
-
- /// isReMaterializable - Returns true if every definition of MI of every
- /// val# of the specified interval is re-materializable. Also returns true
- /// by reference if all of the defs are load instructions.
- bool isReMaterializable(const LiveInterval &li,
- SmallVectorImpl<LiveInterval*> &SpillIs,
- bool &isLoad);
-
- /// isReMaterializable - Returns true if the definition MI of the specified
- /// val# of the specified interval is re-materializable.
- bool isReMaterializable(const LiveInterval &li, const VNInfo *ValNo,
- MachineInstr *MI);
-
- /// getRepresentativeReg - Find the largest super register of the specified
- /// physical register.
- unsigned getRepresentativeReg(unsigned Reg) const;
-
- /// getNumConflictsWithPhysReg - Return the number of uses and defs of the
- /// specified interval that conflicts with the specified physical register.
- unsigned getNumConflictsWithPhysReg(const LiveInterval &li,
- unsigned PhysReg) const;
-
- /// processImplicitDefs - Process IMPLICIT_DEF instructions. Add isUndef
- /// marker to implicit_def defs and their uses.
- void processImplicitDefs();
-
- /// computeNumbering - Compute the index numbering.
- void computeNumbering();
-
- /// scaleNumbering - Rescale interval numbers to introduce gaps for new
- /// instructions
- void scaleNumbering(int factor);
-
- /// intervalIsInOneMBB - Returns true if the specified interval is entirely
- /// within a single basic block.
- bool intervalIsInOneMBB(const LiveInterval &li) const;
-
- private:
+ /// intervalIsInOneMBB - If LI is confined to a single basic block, return
+ /// a pointer to that block. If LI is live in to or out of any block,
+ /// return NULL.
+ MachineBasicBlock *intervalIsInOneMBB(const LiveInterval &LI) const;
+
+ /// Returns true if VNI is killed by any PHI-def values in LI.
+ /// This may conservatively return true to avoid expensive computations.
+ bool hasPHIKill(const LiveInterval &LI, const VNInfo *VNI) const;
+
+ /// addKillFlags - Add kill flags to any instruction that kills a virtual
+ /// register.
+ void addKillFlags(const VirtRegMap*);
+
+ /// handleMove - call this method to notify LiveIntervals that
+ /// instruction 'mi' has been moved within a basic block. This will update
+ /// the live intervals for all operands of mi. Moves between basic blocks
+ /// are not supported.
+ ///
+ /// \param UpdateFlags Update live intervals for nonallocatable physregs.
+ void handleMove(MachineInstr* MI, bool UpdateFlags = false);
+
+ /// moveIntoBundle - Update intervals for operands of MI so that they
+ /// begin/end on the SlotIndex for BundleStart.
+ ///
+ /// \param UpdateFlags Update live intervals for nonallocatable physregs.
+ ///
+ /// Requires MI and BundleStart to have SlotIndexes, and assumes
+ /// existing liveness is accurate. BundleStart should be the first
+ /// instruction in the Bundle.
+ void handleMoveIntoBundle(MachineInstr* MI, MachineInstr* BundleStart,
+ bool UpdateFlags = false);
+
+ // Register mask functions.
+ //
+ // Machine instructions may use a register mask operand to indicate that a
+ // large number of registers are clobbered by the instruction. This is
+ // typically used for calls.
+ //
+ // For compile time performance reasons, these clobbers are not recorded in
+ // the live intervals for individual physical registers. Instead,
+ // LiveIntervalAnalysis maintains a sorted list of instructions with
+ // register mask operands.
+
+ /// getRegMaskSlots - Returns a sorted array of slot indices of all
+ /// instructions with register mask operands.
+ ArrayRef<SlotIndex> getRegMaskSlots() const { return RegMaskSlots; }
+
+ /// getRegMaskSlotsInBlock - Returns a sorted array of slot indices of all
+ /// instructions with register mask operands in the basic block numbered
+ /// MBBNum.
+ ArrayRef<SlotIndex> getRegMaskSlotsInBlock(unsigned MBBNum) const {
+ std::pair<unsigned, unsigned> P = RegMaskBlocks[MBBNum];
+ return getRegMaskSlots().slice(P.first, P.second);
+ }
+
+ /// getRegMaskBits() - Returns an array of register mask pointers
+ /// corresponding to getRegMaskSlots().
+ ArrayRef<const uint32_t*> getRegMaskBits() const { return RegMaskBits; }
+
+ /// getRegMaskBitsInBlock - Returns an array of mask pointers corresponding
+ /// to getRegMaskSlotsInBlock(MBBNum).
+ ArrayRef<const uint32_t*> getRegMaskBitsInBlock(unsigned MBBNum) const {
+ std::pair<unsigned, unsigned> P = RegMaskBlocks[MBBNum];
+ return getRegMaskBits().slice(P.first, P.second);
+ }
+
+ /// checkRegMaskInterference - Test if LI is live across any register mask
+ /// instructions, and compute a bit mask of physical registers that are not
+ /// clobbered by any of them.
+ ///
+ /// Returns false if LI doesn't cross any register mask instructions. In
+ /// that case, the bit vector is not filled in.
+ bool checkRegMaskInterference(LiveInterval &LI,
+ BitVector &UsableRegs);
+
+ // Register unit functions.
+ //
+ // Fixed interference occurs when MachineInstrs use physregs directly
+ // instead of virtual registers. This typically happens when passing
+ // arguments to a function call, or when instructions require operands in
+ // fixed registers.
+ //
+ // Each physreg has one or more register units, see MCRegisterInfo. We
+ // track liveness per register unit to handle aliasing registers more
+ // efficiently.
+
+ /// getRegUnit - Return the live range for Unit.
+ /// It will be computed if it doesn't exist.
+ LiveInterval &getRegUnit(unsigned Unit) {
+ LiveInterval *LI = RegUnitIntervals[Unit];
+ if (!LI) {
+ // Compute missing ranges on demand.
+ RegUnitIntervals[Unit] = LI = new LiveInterval(Unit, HUGE_VALF);
+ computeRegUnitInterval(LI);
+ }
+ return *LI;
+ }
+
+ /// getCachedRegUnit - Return the live range for Unit if it has already
+ /// been computed, or NULL if it hasn't been computed yet.
+ LiveInterval *getCachedRegUnit(unsigned Unit) {
+ return RegUnitIntervals[Unit];
+ }
+
+ const LiveInterval *getCachedRegUnit(unsigned Unit) const {
+ return RegUnitIntervals[Unit];
+ }
+
+ private:
/// computeIntervals - Compute live intervals.
void computeIntervals();
- bool isProfitableToCoalesce(LiveInterval &DstInt, LiveInterval &SrcInt,
- SmallVector<MachineInstr*,16> &IdentCopies,
- SmallVector<MachineInstr*,16> &OtherCopies,
- bool &HaveConflict);
+ /// Compute live intervals for all virtual registers.
+ void computeVirtRegs();
- void performEarlyCoalescing();
+ /// Compute RegMaskSlots and RegMaskBits.
+ void computeRegMasks();
/// handleRegisterDef - update intervals for a register def
- /// (calls handlePhysicalRegisterDef and
- /// handleVirtualRegisterDef)
+ /// (calls handleVirtualRegisterDef)
void handleRegisterDef(MachineBasicBlock *MBB,
MachineBasicBlock::iterator MI,
- MachineInstrIndex MIIdx,
+ SlotIndex MIIdx,
MachineOperand& MO, unsigned MOIdx);
+ /// isPartialRedef - Return true if the specified def at the specific index
+ /// is partially re-defining the specified live interval. A common case of
+ /// this is a definition of the sub-register.
+ bool isPartialRedef(SlotIndex MIIdx, MachineOperand &MO,
+ LiveInterval &interval);
+
/// handleVirtualRegisterDef - update intervals for a virtual
/// register def
void handleVirtualRegisterDef(MachineBasicBlock *MBB,
MachineBasicBlock::iterator MI,
- MachineInstrIndex MIIdx, MachineOperand& MO,
+ SlotIndex MIIdx, MachineOperand& MO,
unsigned MOIdx,
LiveInterval& interval);
- /// handlePhysicalRegisterDef - update intervals for a physical register
- /// def.
- void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
- MachineBasicBlock::iterator mi,
- MachineInstrIndex MIIdx, MachineOperand& MO,
- LiveInterval &interval,
- MachineInstr *CopyMI);
-
- /// handleLiveInRegister - Create interval for a livein register.
- void handleLiveInRegister(MachineBasicBlock* mbb,
- MachineInstrIndex MIIdx,
- LiveInterval &interval, bool isAlias = false);
-
- /// getReMatImplicitUse - If the remat definition MI has one (for now, we
- /// only allow one) virtual register operand, then its uses are implicitly
- /// using the register. Returns the virtual register.
- unsigned getReMatImplicitUse(const LiveInterval &li,
- MachineInstr *MI) const;
-
- /// isValNoAvailableAt - Return true if the val# of the specified interval
- /// which reaches the given instruction also reaches the specified use
- /// index.
- bool isValNoAvailableAt(const LiveInterval &li, MachineInstr *MI,
- MachineInstrIndex UseIdx) const;
-
- /// isReMaterializable - Returns true if the definition MI of the specified
- /// val# of the specified interval is re-materializable. Also returns true
- /// by reference if the def is a load.
- bool isReMaterializable(const LiveInterval &li, const VNInfo *ValNo,
- MachineInstr *MI,
- SmallVectorImpl<LiveInterval*> &SpillIs,
- bool &isLoad);
-
- /// tryFoldMemoryOperand - Attempts to fold either a spill / restore from
- /// slot / to reg or any rematerialized load into ith operand of specified
- /// MI. If it is successul, MI is updated with the newly created MI and
- /// returns true.
- bool tryFoldMemoryOperand(MachineInstr* &MI, VirtRegMap &vrm,
- MachineInstr *DefMI, MachineInstrIndex InstrIdx,
- SmallVector<unsigned, 2> &Ops,
- bool isSS, int FrameIndex, unsigned Reg);
-
- /// canFoldMemoryOperand - Return true if the specified load / store
- /// folding is possible.
- bool canFoldMemoryOperand(MachineInstr *MI,
- SmallVector<unsigned, 2> &Ops,
- bool ReMatLoadSS) const;
-
- /// anyKillInMBBAfterIdx - Returns true if there is a kill of the specified
- /// VNInfo that's after the specified index but is within the basic block.
- bool anyKillInMBBAfterIdx(const LiveInterval &li, const VNInfo *VNI,
- MachineBasicBlock *MBB,
- MachineInstrIndex Idx) const;
-
- /// hasAllocatableSuperReg - Return true if the specified physical register
- /// has any super register that's allocatable.
- bool hasAllocatableSuperReg(unsigned Reg) const;
-
- /// SRInfo - Spill / restore info.
- struct SRInfo {
- MachineInstrIndex index;
- unsigned vreg;
- bool canFold;
- SRInfo(MachineInstrIndex i, unsigned vr, bool f)
- : index(i), vreg(vr), canFold(f) {}
- };
-
- bool alsoFoldARestore(int Id, MachineInstrIndex index, unsigned vr,
- BitVector &RestoreMBBs,
- DenseMap<unsigned,std::vector<SRInfo> >&RestoreIdxes);
- void eraseRestoreInfo(int Id, MachineInstrIndex index, unsigned vr,
- BitVector &RestoreMBBs,
- DenseMap<unsigned,std::vector<SRInfo> >&RestoreIdxes);
-
- /// handleSpilledImpDefs - Remove IMPLICIT_DEF instructions which are being
- /// spilled and create empty intervals for their uses.
- void handleSpilledImpDefs(const LiveInterval &li, VirtRegMap &vrm,
- const TargetRegisterClass* rc,
- std::vector<LiveInterval*> &NewLIs);
-
- /// rewriteImplicitOps - Rewrite implicit use operands of MI (i.e. uses of
- /// interval on to-be re-materialized operands of MI) with new register.
- void rewriteImplicitOps(const LiveInterval &li,
- MachineInstr *MI, unsigned NewVReg, VirtRegMap &vrm);
-
- /// rewriteInstructionForSpills, rewriteInstructionsForSpills - Helper
- /// functions for addIntervalsForSpills to rewrite uses / defs for the given
- /// live range.
- bool rewriteInstructionForSpills(const LiveInterval &li, const VNInfo *VNI,
- bool TrySplit, MachineInstrIndex index, MachineInstrIndex end,
- MachineInstr *MI, MachineInstr *OrigDefMI, MachineInstr *DefMI,
- unsigned Slot, int LdSlot,
- bool isLoad, bool isLoadSS, bool DefIsReMat, bool CanDelete,
- VirtRegMap &vrm, const TargetRegisterClass* rc,
- SmallVector<int, 4> &ReMatIds, const MachineLoopInfo *loopInfo,
- unsigned &NewVReg, unsigned ImpUse, bool &HasDef, bool &HasUse,
- DenseMap<unsigned,unsigned> &MBBVRegsMap,
- std::vector<LiveInterval*> &NewLIs);
- void rewriteInstructionsForSpills(const LiveInterval &li, bool TrySplit,
- LiveInterval::Ranges::const_iterator &I,
- MachineInstr *OrigDefMI, MachineInstr *DefMI, unsigned Slot, int LdSlot,
- bool isLoad, bool isLoadSS, bool DefIsReMat, bool CanDelete,
- VirtRegMap &vrm, const TargetRegisterClass* rc,
- SmallVector<int, 4> &ReMatIds, const MachineLoopInfo *loopInfo,
- BitVector &SpillMBBs,
- DenseMap<unsigned,std::vector<SRInfo> > &SpillIdxes,
- BitVector &RestoreMBBs,
- DenseMap<unsigned,std::vector<SRInfo> > &RestoreIdxes,
- DenseMap<unsigned,unsigned> &MBBVRegsMap,
- std::vector<LiveInterval*> &NewLIs);
-
static LiveInterval* createInterval(unsigned Reg);
void printInstrs(raw_ostream &O) const;
void dumpInstrs() const;
+
+ void computeLiveInRegUnits();
+ void computeRegUnitInterval(LiveInterval*);
+ void computeVirtRegInterval(LiveInterval*);
+
+ class HMEditor;
};
} // End llvm namespace