X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FSimpleRegisterCoalescing.h;h=65cf542836dd5a4c18a831def84ec730a07e79db;hb=bcb8c6d09ee426e0f774e3412912f6ae9e5f78dd;hp=cae5e5a450e17d3d3f6ea4238dfb593f576fabc4;hpb=c8d044e4f779fdcfc5e7d592927740fd8f672a70;p=oota-llvm.git diff --git a/lib/CodeGen/SimpleRegisterCoalescing.h b/lib/CodeGen/SimpleRegisterCoalescing.h index cae5e5a450e..65cf542836d 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.h +++ b/lib/CodeGen/SimpleRegisterCoalescing.h @@ -15,16 +15,13 @@ #define LLVM_CODEGEN_SIMPLE_REGISTER_COALESCING_H #include "llvm/CodeGen/MachineFunctionPass.h" -#include "llvm/CodeGen/LiveInterval.h" #include "llvm/CodeGen/LiveIntervalAnalysis.h" #include "llvm/CodeGen/RegisterCoalescer.h" #include "llvm/ADT/BitVector.h" -#include "llvm/ADT/IndexedMap.h" -#include namespace llvm { class SimpleRegisterCoalescing; - class LiveVariables; + class LiveDebugVariables; class TargetRegisterInfo; class TargetInstrInfo; class VirtRegMap; @@ -35,44 +32,8 @@ namespace llvm { struct CopyRec { MachineInstr *MI; unsigned LoopDepth; - bool isBackEdge; - CopyRec(MachineInstr *mi, unsigned depth, bool be) - : MI(mi), LoopDepth(depth), isBackEdge(be) {}; - }; - - template class JoinPriorityQueue; - - /// CopyRecSort - Sorting function for coalescer queue. - /// - struct CopyRecSort : public std::binary_function { - JoinPriorityQueue *JPQ; - explicit CopyRecSort(JoinPriorityQueue *jpq) : JPQ(jpq) {} - CopyRecSort(const CopyRecSort &RHS) : JPQ(RHS.JPQ) {} - bool operator()(CopyRec left, CopyRec right) const; - }; - - /// JoinQueue - A priority queue of copy instructions the coalescer is - /// going to process. - template - class JoinPriorityQueue { - SimpleRegisterCoalescing *Rc; - std::priority_queue, SF> Queue; - - public: - explicit JoinPriorityQueue(SimpleRegisterCoalescing *rc) - : Rc(rc), Queue(SF(this)) {} - - bool empty() const { return Queue.empty(); } - void push(CopyRec R) { Queue.push(R); } - CopyRec pop() { - if (empty()) return CopyRec(0, 0, false); - CopyRec R = Queue.top(); - Queue.pop(); - return R; - } - - // Callbacks to SimpleRegisterCoalescing. - unsigned getRepIntervalSize(unsigned Reg); + CopyRec(MachineInstr *mi, unsigned depth) + : MI(mi), LoopDepth(depth) {} }; class SimpleRegisterCoalescing : public MachineFunctionPass, @@ -83,34 +44,30 @@ namespace llvm { const TargetRegisterInfo* tri_; const TargetInstrInfo* tii_; LiveIntervals *li_; - LiveVariables *lv_; + LiveDebugVariables *ldv_; const MachineLoopInfo* loopInfo; + AliasAnalysis *AA; - BitVector allocatableRegs_; DenseMap allocatableRCRegs_; - /// JoinQueue - A priority queue of copy instructions the coalescer is - /// going to process. - JoinPriorityQueue *JoinQueue; - /// JoinedCopies - Keep track of copies eliminated due to coalescing. /// SmallPtrSet JoinedCopies; + /// ReMatCopies - Keep track of copies eliminated due to remat. + /// + SmallPtrSet ReMatCopies; + + /// ReMatDefs - Keep track of definition instructions which have + /// been remat'ed. + SmallPtrSet ReMatDefs; + public: static char ID; // Pass identifcation, replacement for typeid - SimpleRegisterCoalescing() : MachineFunctionPass((intptr_t)&ID) {} - - struct InstrSlots { - enum { - LOAD = 0, - USE = 1, - DEF = 2, - STORE = 3, - NUM = 4 - }; - }; - + SimpleRegisterCoalescing() : MachineFunctionPass(ID) { + initializeSimpleRegisterCoalescingPass(*PassRegistry::getPassRegistry()); + } + virtual void getAnalysisUsage(AnalysisUsage &AU) const; virtual void releaseMemory(); @@ -120,21 +77,10 @@ namespace llvm { bool coalesceFunction(MachineFunction &mf, RegallocQuery &) { // This runs as an independent pass, so don't do anything. return false; - }; - - /// getRepIntervalSize - Called from join priority queue sorting function. - /// It returns the size of the interval that represent the given register. - unsigned getRepIntervalSize(unsigned Reg) { - if (!li_->hasInterval(Reg)) - return 0; - return li_->getInterval(Reg).getSize(); } /// print - Implement the dump method. - virtual void print(std::ostream &O, const Module* = 0) const; - void print(std::ostream *O, const Module* M = 0) const { - if (O) print(*O, M); - } + virtual void print(raw_ostream &O, const Module* = 0) const; private: /// joinIntervals - join compatible live intervals @@ -151,69 +97,91 @@ namespace llvm { /// possible to coalesce this interval, but it may be possible if other /// things get coalesced, then it returns true by reference in 'Again'. bool JoinCopy(CopyRec &TheCopy, bool &Again); - + /// JoinIntervals - Attempt to join these two intervals. On failure, this - /// returns false. Otherwise, if one of the intervals being joined is a - /// physreg, this method always canonicalizes DestInt to be it. The output - /// "SrcInt" will not have been modified, so we can use this information - /// below to update aliases. - bool JoinIntervals(LiveInterval &LHS, LiveInterval &RHS, bool &Swapped); - - /// SimpleJoin - Attempt to join the specified interval into this one. The - /// caller of this method must guarantee that the RHS only contains a single - /// value number and that the RHS is not defined by a copy from this - /// interval. This returns false if the intervals are not joinable, or it - /// joins them and returns true. - bool SimpleJoin(LiveInterval &LHS, LiveInterval &RHS); - - /// Return true if the two specified registers belong to different - /// register classes. The registers may be either phys or virt regs. - bool differingRegisterClasses(unsigned RegA, unsigned RegB) const; + /// returns false. The output "SrcInt" will not have been modified, so we can + /// use this information below to update aliases. + bool JoinIntervals(CoalescerPair &CP); + /// Return true if the two specified registers belong to different register + /// classes. The registers may be either phys or virt regs. + bool differingRegisterClasses(unsigned RegA, unsigned RegB) const; /// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If /// the source value number is defined by a copy from the destination reg /// see if we can merge these two destination reg valno# into a single /// value number, eliminating a copy. - bool AdjustCopiesBackFrom(LiveInterval &IntA, LiveInterval &IntB, - MachineInstr *CopyMI); + bool AdjustCopiesBackFrom(const CoalescerPair &CP, MachineInstr *CopyMI); + + /// HasOtherReachingDefs - Return true if there are definitions of IntB + /// other than BValNo val# that can reach uses of AValno val# of IntA. + bool HasOtherReachingDefs(LiveInterval &IntA, LiveInterval &IntB, + VNInfo *AValNo, VNInfo *BValNo); /// RemoveCopyByCommutingDef - We found a non-trivially-coalescable copy. /// If the source value number is defined by a commutable instruction and /// its other operand is coalesced to the copy dest register, see if we /// can transform the copy into a noop by commuting the definition. - bool RemoveCopyByCommutingDef(LiveInterval &IntA, LiveInterval &IntB, - MachineInstr *CopyMI); - - /// RemoveUnnecessaryKills - Remove kill markers that are no longer accurate - /// due to live range lengthening as the result of coalescing. - void RemoveUnnecessaryKills(unsigned Reg, LiveInterval &LI); - - /// isBackEdgeCopy - Returns true if CopyMI is a back edge copy. - /// - bool isBackEdgeCopy(MachineInstr *CopyMI, unsigned DstReg); + bool RemoveCopyByCommutingDef(const CoalescerPair &CP,MachineInstr *CopyMI); + + /// TrimLiveIntervalToLastUse - If there is a last use in the same basic + /// block as the copy instruction, trim the ive interval to the last use + /// and return true. + bool TrimLiveIntervalToLastUse(SlotIndex CopyIdx, + MachineBasicBlock *CopyMBB, + LiveInterval &li, const LiveRange *LR); + + /// ReMaterializeTrivialDef - If the source of a copy is defined by a trivial + /// computation, replace the copy by rematerialize the definition. + /// If PreserveSrcInt is true, make sure SrcInt is valid after the call. + bool ReMaterializeTrivialDef(LiveInterval &SrcInt, bool PreserveSrcInt, + unsigned DstReg, unsigned DstSubIdx, + MachineInstr *CopyMI); + + /// shouldJoinPhys - Return true if a physreg copy should be joined. + bool shouldJoinPhys(CoalescerPair &CP); + + /// isWinToJoinCrossClass - Return true if it's profitable to coalesce + /// two virtual registers from different register classes. + bool isWinToJoinCrossClass(unsigned SrcReg, + unsigned DstReg, + const TargetRegisterClass *SrcRC, + const TargetRegisterClass *DstRC, + const TargetRegisterClass *NewRC); /// UpdateRegDefsUses - Replace all defs and uses of SrcReg to DstReg and /// update the subregister number if it is not zero. If DstReg is a /// physical register and the existing subregister number of the def / use /// being updated is not zero, make sure to set it to the correct physical /// subregister. - void UpdateRegDefsUses(unsigned SrcReg, unsigned DstReg, unsigned SubIdx); + void UpdateRegDefsUses(const CoalescerPair &CP); - /// lastRegisterUse - Returns the last use of the specific register between - /// cycles Start and End or NULL if there are no uses. - MachineOperand *lastRegisterUse(unsigned Start, unsigned End, unsigned Reg, - unsigned &LastUseIdx) const; + /// ShortenDeadCopyLiveRange - Shorten a live range defined by a dead copy. + /// Return true if live interval is removed. + bool ShortenDeadCopyLiveRange(LiveInterval &li, MachineInstr *CopyMI); - /// findDefOperand - Returns the MachineOperand that is a def of the specific - /// register. It returns NULL if the def is not found. - MachineOperand *findDefOperand(MachineInstr *MI, unsigned Reg) const; + /// ShortenDeadCopyLiveRange - Shorten a live range as it's artificially + /// extended by a dead copy. Mark the last use (if any) of the val# as kill + /// as ends the live range there. If there isn't another use, then this + /// live range is dead. Return true if live interval is removed. + bool ShortenDeadCopySrcLiveRange(LiveInterval &li, MachineInstr *CopyMI); - /// unsetRegisterKills - Unset IsKill property of all uses of specific register - /// between cycles Start and End. - void unsetRegisterKills(unsigned Start, unsigned End, unsigned Reg); + /// RemoveDeadDef - If a def of a live interval is now determined dead, + /// remove the val# it defines. If the live interval becomes empty, remove + /// it as well. + bool RemoveDeadDef(LiveInterval &li, MachineInstr *DefMI); + + /// RemoveCopyFlag - If DstReg is no longer defined by CopyMI, clear the + /// VNInfo copy flag for DstReg and all aliases. + void RemoveCopyFlag(unsigned DstReg, const MachineInstr *CopyMI); + + /// lastRegisterUse - Returns the last use of the specific register between + /// cycles Start and End or NULL if there are no uses. + MachineOperand *lastRegisterUse(SlotIndex Start, SlotIndex End, + unsigned Reg, SlotIndex &LastUseIdx) const; - void printRegName(unsigned reg) const; + /// markAsJoined - Remember that CopyMI has already been joined. + void markAsJoined(MachineInstr *CopyMI); }; } // End llvm namespace