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-rw-r--r--include/llvm/CodeGen/LiveIntervalAnalysis.h230
1 files changed, 105 insertions, 125 deletions
diff --git a/include/llvm/CodeGen/LiveIntervalAnalysis.h b/include/llvm/CodeGen/LiveIntervalAnalysis.h
index 76201c9..da521db 100644
--- a/include/llvm/CodeGen/LiveIntervalAnalysis.h
+++ b/include/llvm/CodeGen/LiveIntervalAnalysis.h
@@ -20,12 +20,13 @@
#ifndef LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
#define LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
+#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/CodeGen/SlotIndexes.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/Support/Allocator.h"
@@ -35,7 +36,9 @@
namespace llvm {
class AliasAnalysis;
+ class LiveRangeCalc;
class LiveVariables;
+ class MachineDominatorTree;
class MachineLoopInfo;
class TargetRegisterInfo;
class MachineRegisterInfo;
@@ -44,27 +47,29 @@ namespace llvm {
class VirtRegMap;
class LiveIntervals : public MachineFunctionPass {
- MachineFunction* mf_;
- MachineRegisterInfo* mri_;
- const TargetMachine* tm_;
- const TargetRegisterInfo* tri_;
- const TargetInstrInfo* tii_;
- AliasAnalysis *aa_;
- LiveVariables* lv_;
- SlotIndexes* indexes_;
+ 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#).
///
VNInfo::Allocator VNInfoAllocator;
- typedef DenseMap<unsigned, LiveInterval*> Reg2IntervalMap;
- Reg2IntervalMap r2iMap_;
+ /// Live interval pointers for all the virtual registers.
+ IndexedMap<LiveInterval*, VirtReg2IndexFunctor> VirtRegIntervals;
- /// allocatableRegs_ - A bit vector of allocatable registers.
- BitVector allocatableRegs_;
+ /// AllocatableRegs - A bit vector of allocatable registers.
+ BitVector AllocatableRegs;
- /// reservedRegs_ - A bit vector of reserved registers.
- BitVector reservedRegs_;
+ /// ReservedRegs - A bit vector of reserved registers.
+ BitVector ReservedRegs;
/// RegMaskSlots - Sorted list of instructions with register mask operands.
/// Always use the 'r' slot, RegMasks are normal clobbers, not early
@@ -92,83 +97,59 @@ namespace llvm {
/// 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) {
- initializeLiveIntervalsPass(*PassRegistry::getPassRegistry());
- }
+ LiveIntervals();
+ virtual ~LiveIntervals();
// Calculate the spill weight to assign to a single instruction.
static float getSpillWeight(bool isDef, bool isUse, unsigned 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;
+ LiveInterval &getInterval(unsigned Reg) {
+ LiveInterval *LI = VirtRegIntervals[Reg];
+ assert(LI && "Interval does not exist for virtual register");
+ return *LI;
}
- 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;
+ const LiveInterval &getInterval(unsigned Reg) const {
+ return const_cast<LiveIntervals*>(this)->getInterval(Reg);
}
- bool hasInterval(unsigned reg) const {
- return r2iMap_.count(reg);
+ bool hasInterval(unsigned Reg) const {
+ return VirtRegIntervals.inBounds(Reg) && VirtRegIntervals[Reg];
}
/// isAllocatable - is the physical register reg allocatable in the current
/// function?
bool isAllocatable(unsigned reg) const {
- return allocatableRegs_.test(reg);
+ return AllocatableRegs.test(reg);
}
/// isReserved - is the physical register reg reserved in the current
/// function
bool isReserved(unsigned reg) const {
- return reservedRegs_.test(reg);
- }
-
- /// 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 * I.getSize()) / indexes_->getIndexesLength();
- }
-
- /// getFuncInstructionCount - Return the number of instructions in the
- /// current function.
- unsigned getFuncInstructionCount() {
- return indexes_->getFunctionSize();
+ return ReservedRegs.test(reg);
}
- /// 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 * indexes_->getFunctionSize());
+ // Interval creation.
+ LiveInterval &getOrCreateInterval(unsigned Reg) {
+ if (!hasInterval(Reg)) {
+ VirtRegIntervals.grow(Reg);
+ VirtRegIntervals[Reg] = createInterval(Reg);
+ }
+ return getInterval(Reg);
}
- // 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;
+ // Interval removal.
+ void removeInterval(unsigned Reg) {
+ delete VirtRegIntervals[Reg];
+ VirtRegIntervals[Reg] = 0;
}
- /// 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,
@@ -184,42 +165,38 @@ namespace llvm {
bool shrinkToUses(LiveInterval *li,
SmallVectorImpl<MachineInstr*> *dead = 0);
- // Interval removal
-
- void removeInterval(unsigned Reg) {
- DenseMap<unsigned, LiveInterval*>::iterator I = r2iMap_.find(Reg);
- delete I->second;
- r2iMap_.erase(I);
+ SlotIndexes *getSlotIndexes() const {
+ return Indexes;
}
- SlotIndexes *getSlotIndexes() const {
- return indexes_;
+ AliasAnalysis *getAliasAnalysis() const {
+ return AA;
}
/// 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);
+ return !Indexes->hasIndex(Instr);
}
/// Returns the base index of the given instruction.
SlotIndex getInstructionIndex(const MachineInstr *instr) const {
- return indexes_->getInstructionIndex(instr);
+ return Indexes->getInstructionIndex(instr);
}
/// Returns the instruction associated with the given index.
MachineInstr* getInstructionFromIndex(SlotIndex index) const {
- return indexes_->getInstructionFromIndex(index);
+ return Indexes->getInstructionFromIndex(index);
}
/// Return the first index in the given basic block.
SlotIndex getMBBStartIdx(const MachineBasicBlock *mbb) const {
- return indexes_->getMBBStartIdx(mbb);
+ return Indexes->getMBBStartIdx(mbb);
}
/// Return the last index in the given basic block.
SlotIndex getMBBEndIdx(const MachineBasicBlock *mbb) const {
- return indexes_->getMBBEndIdx(mbb);
+ return Indexes->getMBBEndIdx(mbb);
}
bool isLiveInToMBB(const LiveInterval &li,
@@ -233,24 +210,24 @@ namespace llvm {
}
MachineBasicBlock* getMBBFromIndex(SlotIndex index) const {
- return indexes_->getMBBFromIndex(index);
+ return Indexes->getMBBFromIndex(index);
}
SlotIndex InsertMachineInstrInMaps(MachineInstr *MI) {
- return indexes_->insertMachineInstrInMaps(MI);
+ return Indexes->insertMachineInstrInMaps(MI);
}
void RemoveMachineInstrFromMaps(MachineInstr *MI) {
- indexes_->removeMachineInstrFromMaps(MI);
+ Indexes->removeMachineInstrFromMaps(MI);
}
void ReplaceMachineInstrInMaps(MachineInstr *MI, MachineInstr *NewMI) {
- indexes_->replaceMachineInstrInMaps(MI, NewMI);
+ Indexes->replaceMachineInstrInMaps(MI, NewMI);
}
bool findLiveInMBBs(SlotIndex Start, SlotIndex End,
SmallVectorImpl<MachineBasicBlock*> &MBBs) const {
- return indexes_->findLiveInMBBs(Start, End, MBBs);
+ return Indexes->findLiveInMBBs(Start, End, MBBs);
}
VNInfo::Allocator& getVNInfoAllocator() { return VNInfoAllocator; }
@@ -264,18 +241,15 @@ namespace llvm {
/// print - Implement the dump method.
virtual void print(raw_ostream &O, const Module* = 0) const;
- /// 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,
- const SmallVectorImpl<LiveInterval*> *SpillIs,
- bool &isLoad);
-
/// 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();
@@ -337,13 +311,47 @@ namespace llvm {
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];
+ }
+
private:
/// computeIntervals - Compute live intervals.
void computeIntervals();
+ /// Compute live intervals for all virtual registers.
+ void computeVirtRegs();
+
+ /// 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,
SlotIndex MIIdx,
@@ -363,43 +371,15 @@ namespace llvm {
unsigned MOIdx,
LiveInterval& interval);
- /// handlePhysicalRegisterDef - update intervals for a physical register
- /// def.
- void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
- MachineBasicBlock::iterator mi,
- SlotIndex MIIdx, MachineOperand& MO,
- LiveInterval &interval);
-
- /// handleLiveInRegister - Create interval for a livein register.
- void handleLiveInRegister(MachineBasicBlock* mbb,
- SlotIndex MIIdx,
- LiveInterval &interval);
-
- /// 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,
- SlotIndex 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,
- const SmallVectorImpl<LiveInterval*> *SpillIs,
- bool &isLoad);
-
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
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