X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;ds=sidebyside;f=include%2Fllvm%2FCodeGen%2FMachineBasicBlock.h;h=8ebc8bd02cb4f92a1ecd32b50e3b88430a7916a4;hb=ee97a1a33b2cb1173e0b4c601ed5976e56654063;hp=023f9b6564e56a1af2ff12495efd47fb183a810d;hpb=4bde1ab82d4a520dca59db1fd212d77ac667b3a8;p=oota-llvm.git diff --git a/include/llvm/CodeGen/MachineBasicBlock.h b/include/llvm/CodeGen/MachineBasicBlock.h index 023f9b6564e..8ebc8bd02cb 100644 --- a/include/llvm/CodeGen/MachineBasicBlock.h +++ b/include/llvm/CodeGen/MachineBasicBlock.h @@ -14,14 +14,26 @@ #ifndef LLVM_CODEGEN_MACHINEBASICBLOCK_H #define LLVM_CODEGEN_MACHINEBASICBLOCK_H -#include "llvm/CodeGen/MachineInstr.h" #include "llvm/ADT/GraphTraits.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/MC/MCRegisterInfo.h" +#include "llvm/Support/DataTypes.h" +#include namespace llvm { +class Pass; class BasicBlock; class MachineFunction; +class MCSymbol; +class MIPrinter; +class SlotIndexes; +class StringRef; class raw_ostream; +class MachineBranchProbabilityInfo; + +// Forward declaration to avoid circular include problem with TargetRegisterInfo +typedef unsigned LaneBitmask; template <> struct ilist_traits : public ilist_default_traits { @@ -45,45 +57,74 @@ public: void addNodeToList(MachineInstr* N); void removeNodeFromList(MachineInstr* N); void transferNodesFromList(ilist_traits &SrcTraits, - ilist_iterator first, - ilist_iterator last); + ilist_iterator First, + ilist_iterator Last); void deleteNode(MachineInstr *N); private: void createNode(const MachineInstr &); }; class MachineBasicBlock : public ilist_node { +public: + /// Pair of physical register and lane mask. + /// This is not simply a std::pair typedef because the members should be named + /// clearly as they both have an integer type. + struct RegisterMaskPair { + public: + MCPhysReg PhysReg; + LaneBitmask LaneMask; + + RegisterMaskPair(MCPhysReg PhysReg, LaneBitmask LaneMask) + : PhysReg(PhysReg), LaneMask(LaneMask) {} + }; + +private: typedef ilist Instructions; Instructions Insts; const BasicBlock *BB; int Number; MachineFunction *xParent; - - /// Predecessors/Successors - Keep track of the predecessor / successor - /// basicblocks. + + /// Keep track of the predecessor / successor basic blocks. std::vector Predecessors; std::vector Successors; - /// LiveIns - Keep track of the physical registers that are livein of - /// the basicblock. - std::vector LiveIns; + /// Keep track of the weights to the successors. This vector has the same + /// order as Successors, or it is empty if we don't use it (disable + /// optimization). + std::vector Weights; + typedef std::vector::iterator weight_iterator; + typedef std::vector::const_iterator const_weight_iterator; + + /// Keep track of the physical registers that are livein of the basicblock. + typedef std::vector LiveInVector; + LiveInVector LiveIns; - /// Alignment - Alignment of the basic block. Zero if the basic block does - /// not need to be aligned. - unsigned Alignment; - - /// IsLandingPad - Indicate that this basic block is entered via an - /// exception handler. - bool IsLandingPad; + /// Alignment of the basic block. Zero if the basic block does not need to be + /// aligned. The alignment is specified as log2(bytes). + unsigned Alignment = 0; - /// AddressTaken - Indicate that this basic block is potentially the - /// target of an indirect branch. - bool AddressTaken; + /// Indicate that this basic block is entered via an exception handler. + bool IsEHPad = false; + + /// Indicate that this basic block is potentially the target of an indirect + /// branch. + bool AddressTaken = false; + + /// Indicate that this basic block is the entry block of an EH funclet. + bool IsEHFuncletEntry = false; + + /// Indicate that this basic block is the entry block of a cleanup funclet. + bool IsCleanupFuncletEntry = false; + + /// \brief since getSymbol is a relatively heavy-weight operation, the symbol + /// is only computed once and is cached. + mutable MCSymbol *CachedMCSymbol = nullptr; // Intrusive list support MachineBasicBlock() {} - explicit MachineBasicBlock(MachineFunction &mf, const BasicBlock *bb); + explicit MachineBasicBlock(MachineFunction &MF, const BasicBlock *BB); ~MachineBasicBlock(); @@ -91,50 +132,143 @@ class MachineBasicBlock : public ilist_node { friend class MachineFunction; public: - /// getBasicBlock - Return the LLVM basic block that this instance - /// corresponded to originally. Note that this may be NULL if this instance - /// does not correspond directly to an LLVM basic block. - /// + /// Return the LLVM basic block that this instance corresponded to originally. + /// Note that this may be NULL if this instance does not correspond directly + /// to an LLVM basic block. const BasicBlock *getBasicBlock() const { return BB; } - /// getName - Return the name of the corresponding LLVM basic block, or - /// "(null)". + /// Return the name of the corresponding LLVM basic block, or "(null)". StringRef getName() const; - /// hasAddressTaken - Test whether this block is potentially the target - /// of an indirect branch. + /// Return a formatted string to identify this block and its parent function. + std::string getFullName() const; + + /// Test whether this block is potentially the target of an indirect branch. bool hasAddressTaken() const { return AddressTaken; } - /// setHasAddressTaken - Set this block to reflect that it potentially - /// is the target of an indirect branch. + /// Set this block to reflect that it potentially is the target of an indirect + /// branch. void setHasAddressTaken() { AddressTaken = true; } - /// getParent - Return the MachineFunction containing this basic block. - /// + /// Return the MachineFunction containing this basic block. const MachineFunction *getParent() const { return xParent; } MachineFunction *getParent() { return xParent; } - typedef Instructions::iterator iterator; - typedef Instructions::const_iterator const_iterator; - typedef std::reverse_iterator const_reverse_iterator; - typedef std::reverse_iterator reverse_iterator; + /// MachineBasicBlock iterator that automatically skips over MIs that are + /// inside bundles (i.e. walk top level MIs only). + template + class bundle_iterator + : public std::iterator { + IterTy MII; + + public: + bundle_iterator(IterTy MI) : MII(MI) {} + + bundle_iterator(Ty &MI) : MII(MI) { + assert(!MI.isBundledWithPred() && + "It's not legal to initialize bundle_iterator with a bundled MI"); + } + bundle_iterator(Ty *MI) : MII(MI) { + assert((!MI || !MI->isBundledWithPred()) && + "It's not legal to initialize bundle_iterator with a bundled MI"); + } + // Template allows conversion from const to nonconst. + template + bundle_iterator(const bundle_iterator &I) + : MII(I.getInstrIterator()) {} + bundle_iterator() : MII(nullptr) {} + + Ty &operator*() const { return *MII; } + Ty *operator->() const { return &operator*(); } + + operator Ty*() const { return MII; } + + bool operator==(const bundle_iterator &X) const { + return MII == X.MII; + } + bool operator!=(const bundle_iterator &X) const { + return !operator==(X); + } + + // Increment and decrement operators... + bundle_iterator &operator--() { // predecrement - Back up + do --MII; + while (MII->isBundledWithPred()); + return *this; + } + bundle_iterator &operator++() { // preincrement - Advance + while (MII->isBundledWithSucc()) + ++MII; + ++MII; + return *this; + } + bundle_iterator operator--(int) { // postdecrement operators... + bundle_iterator tmp = *this; + --*this; + return tmp; + } + bundle_iterator operator++(int) { // postincrement operators... + bundle_iterator tmp = *this; + ++*this; + return tmp; + } + + IterTy getInstrIterator() const { + return MII; + } + }; + + typedef Instructions::iterator instr_iterator; + typedef Instructions::const_iterator const_instr_iterator; + typedef std::reverse_iterator reverse_instr_iterator; + typedef + std::reverse_iterator const_reverse_instr_iterator; + + typedef + bundle_iterator iterator; + typedef + bundle_iterator const_iterator; + typedef std::reverse_iterator const_reverse_iterator; + typedef std::reverse_iterator reverse_iterator; + unsigned size() const { return (unsigned)Insts.size(); } bool empty() const { return Insts.empty(); } - MachineInstr& front() { return Insts.front(); } - MachineInstr& back() { return Insts.back(); } - const MachineInstr& front() const { return Insts.front(); } - const MachineInstr& back() const { return Insts.back(); } - - iterator begin() { return Insts.begin(); } - const_iterator begin() const { return Insts.begin(); } - iterator end() { return Insts.end(); } - const_iterator end() const { return Insts.end(); } - reverse_iterator rbegin() { return Insts.rbegin(); } - const_reverse_iterator rbegin() const { return Insts.rbegin(); } - reverse_iterator rend () { return Insts.rend(); } - const_reverse_iterator rend () const { return Insts.rend(); } + MachineInstr &instr_front() { return Insts.front(); } + MachineInstr &instr_back() { return Insts.back(); } + const MachineInstr &instr_front() const { return Insts.front(); } + const MachineInstr &instr_back() const { return Insts.back(); } + + MachineInstr &front() { return Insts.front(); } + MachineInstr &back() { return *--end(); } + const MachineInstr &front() const { return Insts.front(); } + const MachineInstr &back() const { return *--end(); } + + instr_iterator instr_begin() { return Insts.begin(); } + const_instr_iterator instr_begin() const { return Insts.begin(); } + instr_iterator instr_end() { return Insts.end(); } + const_instr_iterator instr_end() const { return Insts.end(); } + reverse_instr_iterator instr_rbegin() { return Insts.rbegin(); } + const_reverse_instr_iterator instr_rbegin() const { return Insts.rbegin(); } + reverse_instr_iterator instr_rend () { return Insts.rend(); } + const_reverse_instr_iterator instr_rend () const { return Insts.rend(); } + + iterator begin() { return instr_begin(); } + const_iterator begin() const { return instr_begin(); } + iterator end () { return instr_end(); } + const_iterator end () const { return instr_end(); } + reverse_iterator rbegin() { return instr_rbegin(); } + const_reverse_iterator rbegin() const { return instr_rbegin(); } + reverse_iterator rend () { return instr_rend(); } + const_reverse_iterator rend () const { return instr_rend(); } + + inline iterator_range terminators() { + return iterator_range(getFirstTerminator(), end()); + } + inline iterator_range terminators() const { + return iterator_range(getFirstTerminator(), end()); + } // Machine-CFG iterators typedef std::vector::iterator pred_iterator; @@ -149,7 +283,6 @@ public: succ_reverse_iterator; typedef std::vector::const_reverse_iterator const_succ_reverse_iterator; - pred_iterator pred_begin() { return Predecessors.begin(); } const_pred_iterator pred_begin() const { return Predecessors.begin(); } pred_iterator pred_end() { return Predecessors.end(); } @@ -183,205 +316,440 @@ public: } bool succ_empty() const { return Successors.empty(); } + inline iterator_range predecessors() { + return iterator_range(pred_begin(), pred_end()); + } + inline iterator_range predecessors() const { + return iterator_range(pred_begin(), pred_end()); + } + inline iterator_range successors() { + return iterator_range(succ_begin(), succ_end()); + } + inline iterator_range successors() const { + return iterator_range(succ_begin(), succ_end()); + } + // LiveIn management methods. - /// addLiveIn - Add the specified register as a live in. Note that it - /// is an error to add the same register to the same set more than once. - void addLiveIn(unsigned Reg) { LiveIns.push_back(Reg); } + /// Adds the specified register as a live in. Note that it is an error to add + /// the same register to the same set more than once unless the intention is + /// to call sortUniqueLiveIns after all registers are added. + void addLiveIn(MCPhysReg PhysReg, LaneBitmask LaneMask = ~0u) { + LiveIns.push_back(RegisterMaskPair(PhysReg, LaneMask)); + } + void addLiveIn(const RegisterMaskPair &RegMaskPair) { + LiveIns.push_back(RegMaskPair); + } - /// removeLiveIn - Remove the specified register from the live in set. - /// - void removeLiveIn(unsigned Reg); + /// Sorts and uniques the LiveIns vector. It can be significantly faster to do + /// this than repeatedly calling isLiveIn before calling addLiveIn for every + /// LiveIn insertion. + void sortUniqueLiveIns(); - /// isLiveIn - Return true if the specified register is in the live in set. - /// - bool isLiveIn(unsigned Reg) const; + /// Add PhysReg as live in to this block, and ensure that there is a copy of + /// PhysReg to a virtual register of class RC. Return the virtual register + /// that is a copy of the live in PhysReg. + unsigned addLiveIn(MCPhysReg PhysReg, const TargetRegisterClass *RC); + + /// Remove the specified register from the live in set. + void removeLiveIn(MCPhysReg Reg, LaneBitmask LaneMask = ~0u); + + /// Return true if the specified register is in the live in set. + bool isLiveIn(MCPhysReg Reg, LaneBitmask LaneMask = ~0u) const; // Iteration support for live in sets. These sets are kept in sorted // order by their register number. - typedef std::vector::iterator livein_iterator; - typedef std::vector::const_iterator const_livein_iterator; - livein_iterator livein_begin() { return LiveIns.begin(); } - const_livein_iterator livein_begin() const { return LiveIns.begin(); } - livein_iterator livein_end() { return LiveIns.end(); } - const_livein_iterator livein_end() const { return LiveIns.end(); } + typedef LiveInVector::const_iterator livein_iterator; + livein_iterator livein_begin() const { return LiveIns.begin(); } + livein_iterator livein_end() const { return LiveIns.end(); } bool livein_empty() const { return LiveIns.empty(); } + iterator_range liveins() const { + return make_range(livein_begin(), livein_end()); + } - /// getAlignment - Return alignment of the basic block. - /// + /// Return alignment of the basic block. The alignment is specified as + /// log2(bytes). unsigned getAlignment() const { return Alignment; } - /// setAlignment - Set alignment of the basic block. - /// + /// Set alignment of the basic block. The alignment is specified as + /// log2(bytes). void setAlignment(unsigned Align) { Alignment = Align; } - /// isLandingPad - Returns true if the block is a landing pad. That is - /// this basic block is entered via an exception handler. - bool isLandingPad() const { return IsLandingPad; } + /// Returns true if the block is a landing pad. That is this basic block is + /// entered via an exception handler. + bool isEHPad() const { return IsEHPad; } + + /// Indicates the block is a landing pad. That is this basic block is entered + /// via an exception handler. + void setIsEHPad(bool V = true) { IsEHPad = V; } + + /// If this block has a successor that is a landing pad, return it. Otherwise + /// return NULL. + const MachineBasicBlock *getLandingPadSuccessor() const; + + bool hasEHPadSuccessor() const; + + /// Returns true if this is the entry block of an EH funclet. + bool isEHFuncletEntry() const { return IsEHFuncletEntry; } - /// setIsLandingPad - Indicates the block is a landing pad. That is - /// this basic block is entered via an exception handler. - void setIsLandingPad() { IsLandingPad = true; } + /// Indicates if this is the entry block of an EH funclet. + void setIsEHFuncletEntry(bool V = true) { IsEHFuncletEntry = V; } + + /// Returns true if this is the entry block of a cleanup funclet. + bool isCleanupFuncletEntry() const { return IsCleanupFuncletEntry; } + + /// Indicates if this is the entry block of a cleanup funclet. + void setIsCleanupFuncletEntry(bool V = true) { IsCleanupFuncletEntry = V; } // Code Layout methods. - - /// moveBefore/moveAfter - move 'this' block before or after the specified - /// block. This only moves the block, it does not modify the CFG or adjust - /// potential fall-throughs at the end of the block. + + /// Move 'this' block before or after the specified block. This only moves + /// the block, it does not modify the CFG or adjust potential fall-throughs at + /// the end of the block. void moveBefore(MachineBasicBlock *NewAfter); void moveAfter(MachineBasicBlock *NewBefore); - /// updateTerminator - Update the terminator instructions in block to account - /// for changes to the layout. If the block previously used a fallthrough, - /// it may now need a branch, and if it previously used branching it may now - /// be able to use a fallthrough. + /// Update the terminator instructions in block to account for changes to the + /// layout. If the block previously used a fallthrough, it may now need a + /// branch, and if it previously used branching it may now be able to use a + /// fallthrough. void updateTerminator(); // Machine-CFG mutators - - /// addSuccessor - Add succ as a successor of this MachineBasicBlock. - /// The Predecessors list of succ is automatically updated. - /// - void addSuccessor(MachineBasicBlock *succ); - /// removeSuccessor - Remove successor from the successors list of this - /// MachineBasicBlock. The Predecessors list of succ is automatically updated. + /// Add Succ as a successor of this MachineBasicBlock. The Predecessors list + /// of Succ is automatically updated. WEIGHT parameter is stored in Weights + /// list and it may be used by MachineBranchProbabilityInfo analysis to + /// calculate branch probability. /// - void removeSuccessor(MachineBasicBlock *succ); + /// Note that duplicate Machine CFG edges are not allowed. + void addSuccessor(MachineBasicBlock *Succ, uint32_t Weight = 0); - /// removeSuccessor - Remove specified successor from the successors list of - /// this MachineBasicBlock. The Predecessors list of succ is automatically - /// updated. Return the iterator to the element after the one removed. - /// + /// Set successor weight of a given iterator. + void setSuccWeight(succ_iterator I, uint32_t Weight); + + /// Remove successor from the successors list of this MachineBasicBlock. The + /// Predecessors list of Succ is automatically updated. + void removeSuccessor(MachineBasicBlock *Succ); + + /// Remove specified successor from the successors list of this + /// MachineBasicBlock. The Predecessors list of Succ is automatically updated. + /// Return the iterator to the element after the one removed. succ_iterator removeSuccessor(succ_iterator I); - - /// transferSuccessors - Transfers all the successors from MBB to this - /// machine basic block (i.e., copies all the successors fromMBB and - /// remove all the successors from fromMBB). - void transferSuccessors(MachineBasicBlock *fromMBB); - - /// isSuccessor - Return true if the specified MBB is a successor of this - /// block. + + /// Replace successor OLD with NEW and update weight info. + void replaceSuccessor(MachineBasicBlock *Old, MachineBasicBlock *New); + + /// Transfers all the successors from MBB to this machine basic block (i.e., + /// copies all the successors FromMBB and remove all the successors from + /// FromMBB). + void transferSuccessors(MachineBasicBlock *FromMBB); + + /// Transfers all the successors, as in transferSuccessors, and update PHI + /// operands in the successor blocks which refer to FromMBB to refer to this. + void transferSuccessorsAndUpdatePHIs(MachineBasicBlock *FromMBB); + + /// Return true if any of the successors have weights attached to them. + bool hasSuccessorWeights() const { return !Weights.empty(); } + + /// Return true if the specified MBB is a predecessor of this block. + bool isPredecessor(const MachineBasicBlock *MBB) const; + + /// Return true if the specified MBB is a successor of this block. bool isSuccessor(const MachineBasicBlock *MBB) const; - /// isLayoutSuccessor - Return true if the specified MBB will be emitted - /// immediately after this block, such that if this block exits by - /// falling through, control will transfer to the specified MBB. Note - /// that MBB need not be a successor at all, for example if this block - /// ends with an unconditional branch to some other block. + /// Return true if the specified MBB will be emitted immediately after this + /// block, such that if this block exits by falling through, control will + /// transfer to the specified MBB. Note that MBB need not be a successor at + /// all, for example if this block ends with an unconditional branch to some + /// other block. bool isLayoutSuccessor(const MachineBasicBlock *MBB) const; - /// canFallThrough - Return true if the block can implicitly transfer - /// control to the block after it by falling off the end of it. This should - /// return false if it can reach the block after it, but it uses an explicit - /// branch to do so (e.g., a table jump). True is a conservative answer. + /// Return true if the block can implicitly transfer control to the block + /// after it by falling off the end of it. This should return false if it can + /// reach the block after it, but it uses an explicit branch to do so (e.g., a + /// table jump). True is a conservative answer. bool canFallThrough(); - /// getFirstTerminator - returns an iterator to the first terminator - /// instruction of this basic block. If a terminator does not exist, - /// it returns end() + /// Returns a pointer to the first instruction in this block that is not a + /// PHINode instruction. When adding instructions to the beginning of the + /// basic block, they should be added before the returned value, not before + /// the first instruction, which might be PHI. + /// Returns end() is there's no non-PHI instruction. + iterator getFirstNonPHI(); + + /// Return the first instruction in MBB after I that is not a PHI or a label. + /// This is the correct point to insert copies at the beginning of a basic + /// block. + iterator SkipPHIsAndLabels(iterator I); + + /// Returns an iterator to the first terminator instruction of this basic + /// block. If a terminator does not exist, it returns end(). iterator getFirstTerminator(); + const_iterator getFirstTerminator() const { + return const_cast(this)->getFirstTerminator(); + } + + /// Same getFirstTerminator but it ignores bundles and return an + /// instr_iterator instead. + instr_iterator getFirstInstrTerminator(); - /// isOnlyReachableViaFallthough - Return true if this basic block has - /// exactly one predecessor and the control transfer mechanism between - /// the predecessor and this block is a fall-through. - bool isOnlyReachableByFallthrough() const; + /// Returns an iterator to the first non-debug instruction in the basic block, + /// or end(). + iterator getFirstNonDebugInstr(); + const_iterator getFirstNonDebugInstr() const { + return const_cast(this)->getFirstNonDebugInstr(); + } + + /// Returns an iterator to the last non-debug instruction in the basic block, + /// or end(). + iterator getLastNonDebugInstr(); + const_iterator getLastNonDebugInstr() const { + return const_cast(this)->getLastNonDebugInstr(); + } + + /// Convenience function that returns true if the block has no successors and + /// contains a return instruction. + bool isReturnBlock() const { + return !empty() && back().isReturn(); + } + + /// Split the critical edge from this block to the given successor block, and + /// return the newly created block, or null if splitting is not possible. + /// + /// This function updates LiveVariables, MachineDominatorTree, and + /// MachineLoopInfo, as applicable. + MachineBasicBlock *SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P); void pop_front() { Insts.pop_front(); } void pop_back() { Insts.pop_back(); } void push_back(MachineInstr *MI) { Insts.push_back(MI); } + + /// Insert MI into the instruction list before I, possibly inside a bundle. + /// + /// If the insertion point is inside a bundle, MI will be added to the bundle, + /// otherwise MI will not be added to any bundle. That means this function + /// alone can't be used to prepend or append instructions to bundles. See + /// MIBundleBuilder::insert() for a more reliable way of doing that. + instr_iterator insert(instr_iterator I, MachineInstr *M); + + /// Insert a range of instructions into the instruction list before I. template - void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); } - iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); } + void insert(iterator I, IT S, IT E) { + assert((I == end() || I->getParent() == this) && + "iterator points outside of basic block"); + Insts.insert(I.getInstrIterator(), S, E); + } + + /// Insert MI into the instruction list before I. + iterator insert(iterator I, MachineInstr *MI) { + assert((I == end() || I->getParent() == this) && + "iterator points outside of basic block"); + assert(!MI->isBundledWithPred() && !MI->isBundledWithSucc() && + "Cannot insert instruction with bundle flags"); + return Insts.insert(I.getInstrIterator(), MI); + } + + /// Insert MI into the instruction list after I. + iterator insertAfter(iterator I, MachineInstr *MI) { + assert((I == end() || I->getParent() == this) && + "iterator points outside of basic block"); + assert(!MI->isBundledWithPred() && !MI->isBundledWithSucc() && + "Cannot insert instruction with bundle flags"); + return Insts.insertAfter(I.getInstrIterator(), MI); + } + + /// Remove an instruction from the instruction list and delete it. + /// + /// If the instruction is part of a bundle, the other instructions in the + /// bundle will still be bundled after removing the single instruction. + instr_iterator erase(instr_iterator I); + + /// Remove an instruction from the instruction list and delete it. + /// + /// If the instruction is part of a bundle, the other instructions in the + /// bundle will still be bundled after removing the single instruction. + instr_iterator erase_instr(MachineInstr *I) { + return erase(instr_iterator(I)); + } + + /// Remove a range of instructions from the instruction list and delete them. + iterator erase(iterator I, iterator E) { + return Insts.erase(I.getInstrIterator(), E.getInstrIterator()); + } - // erase - Remove the specified element or range from the instruction list. - // These functions delete any instructions removed. - // - iterator erase(iterator I) { return Insts.erase(I); } - iterator erase(iterator I, iterator E) { return Insts.erase(I, E); } - MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); } - void clear() { Insts.clear(); } + /// Remove an instruction or bundle from the instruction list and delete it. + /// + /// If I points to a bundle of instructions, they are all erased. + iterator erase(iterator I) { + return erase(I, std::next(I)); + } - /// splice - Take an instruction from MBB 'Other' at the position From, - /// and insert it into this MBB right before 'where'. - void splice(iterator where, MachineBasicBlock *Other, iterator From) { - Insts.splice(where, Other->Insts, From); + /// Remove an instruction from the instruction list and delete it. + /// + /// If I is the head of a bundle of instructions, the whole bundle will be + /// erased. + iterator erase(MachineInstr *I) { + return erase(iterator(I)); } - /// splice - Take a block of instructions from MBB 'Other' in the range [From, - /// To), and insert them into this MBB right before 'where'. - void splice(iterator where, MachineBasicBlock *Other, iterator From, - iterator To) { - Insts.splice(where, Other->Insts, From, To); + /// Remove the unbundled instruction from the instruction list without + /// deleting it. + /// + /// This function can not be used to remove bundled instructions, use + /// remove_instr to remove individual instructions from a bundle. + MachineInstr *remove(MachineInstr *I) { + assert(!I->isBundled() && "Cannot remove bundled instructions"); + return Insts.remove(I); + } + + /// Remove the possibly bundled instruction from the instruction list + /// without deleting it. + /// + /// If the instruction is part of a bundle, the other instructions in the + /// bundle will still be bundled after removing the single instruction. + MachineInstr *remove_instr(MachineInstr *I); + + void clear() { + Insts.clear(); + } + + /// Take an instruction from MBB 'Other' at the position From, and insert it + /// into this MBB right before 'Where'. + /// + /// If From points to a bundle of instructions, the whole bundle is moved. + void splice(iterator Where, MachineBasicBlock *Other, iterator From) { + // The range splice() doesn't allow noop moves, but this one does. + if (Where != From) + splice(Where, Other, From, std::next(From)); } - /// removeFromParent - This method unlinks 'this' from the containing - /// function, and returns it, but does not delete it. + /// Take a block of instructions from MBB 'Other' in the range [From, To), + /// and insert them into this MBB right before 'Where'. + /// + /// The instruction at 'Where' must not be included in the range of + /// instructions to move. + void splice(iterator Where, MachineBasicBlock *Other, + iterator From, iterator To) { + Insts.splice(Where.getInstrIterator(), Other->Insts, + From.getInstrIterator(), To.getInstrIterator()); + } + + /// This method unlinks 'this' from the containing function, and returns it, + /// but does not delete it. MachineBasicBlock *removeFromParent(); - - /// eraseFromParent - This method unlinks 'this' from the containing - /// function and deletes it. + + /// This method unlinks 'this' from the containing function and deletes it. void eraseFromParent(); - /// ReplaceUsesOfBlockWith - Given a machine basic block that branched to - /// 'Old', change the code and CFG so that it branches to 'New' instead. + /// Given a machine basic block that branched to 'Old', change the code and + /// CFG so that it branches to 'New' instead. void ReplaceUsesOfBlockWith(MachineBasicBlock *Old, MachineBasicBlock *New); - /// BranchesToLandingPad - The basic block branches only to a landing pad or - /// to another basic block which branches only to a landing pad. No other - /// instructions are present other than the unconditional branch. - bool BranchesToLandingPad(const MachineBasicBlock *MBB) const; - - /// CorrectExtraCFGEdges - Various pieces of code can cause excess edges in - /// the CFG to be inserted. If we have proven that MBB can only branch to - /// DestA and DestB, remove any other MBB successors from the CFG. DestA and - /// DestB can be null. Besides DestA and DestB, retain other edges leading - /// to LandingPads (currently there can be only one; we don't check or require - /// that here). Note it is possible that DestA and/or DestB are LandingPads. + /// Various pieces of code can cause excess edges in the CFG to be inserted. + /// If we have proven that MBB can only branch to DestA and DestB, remove any + /// other MBB successors from the CFG. DestA and DestB can be null. Besides + /// DestA and DestB, retain other edges leading to LandingPads (currently + /// there can be only one; we don't check or require that here). Note it is + /// possible that DestA and/or DestB are LandingPads. bool CorrectExtraCFGEdges(MachineBasicBlock *DestA, MachineBasicBlock *DestB, - bool isCond); + bool IsCond); + + /// Find the next valid DebugLoc starting at MBBI, skipping any DBG_VALUE + /// instructions. Return UnknownLoc if there is none. + DebugLoc findDebugLoc(instr_iterator MBBI); + DebugLoc findDebugLoc(iterator MBBI) { + return findDebugLoc(MBBI.getInstrIterator()); + } + + /// Possible outcome of a register liveness query to computeRegisterLiveness() + enum LivenessQueryResult { + LQR_Live, ///< Register is known to be live. + LQR_OverlappingLive, ///< Register itself is not live, but some overlapping + ///< register is. + LQR_Dead, ///< Register is known to be dead. + LQR_Unknown ///< Register liveness not decidable from local + ///< neighborhood. + }; + + /// Return whether (physical) register \p Reg has been ined and not + /// ed as of just before \p Before. + /// + /// Search is localised to a neighborhood of \p Neighborhood instructions + /// before (searching for defs or kills) and \p Neighborhood instructions + /// after (searching just for defs) \p Before. + /// + /// \p Reg must be a physical register. + LivenessQueryResult computeRegisterLiveness(const TargetRegisterInfo *TRI, + unsigned Reg, + const_iterator Before, + unsigned Neighborhood=10) const; // Debugging methods. void dump() const; - void print(raw_ostream &OS) const; + void print(raw_ostream &OS, SlotIndexes* = nullptr) const; + void print(raw_ostream &OS, ModuleSlotTracker &MST, + SlotIndexes * = nullptr) const; - /// getNumber - MachineBasicBlocks are uniquely numbered at the function - /// level, unless they're not in a MachineFunction yet, in which case this - /// will return -1. - /// + // Printing method used by LoopInfo. + void printAsOperand(raw_ostream &OS, bool PrintType = true) const; + + /// MachineBasicBlocks are uniquely numbered at the function level, unless + /// they're not in a MachineFunction yet, in which case this will return -1. int getNumber() const { return Number; } void setNumber(int N) { Number = N; } -private: // Methods used to maintain doubly linked list of blocks... + /// Return the MCSymbol for this basic block. + MCSymbol *getSymbol() const; + + +private: + /// Return weight iterator corresponding to the I successor iterator. + weight_iterator getWeightIterator(succ_iterator I); + const_weight_iterator getWeightIterator(const_succ_iterator I) const; + + friend class MachineBranchProbabilityInfo; + friend class MIPrinter; + + /// Return weight of the edge from this block to MBB. This method should NOT + /// be called directly, but by using getEdgeWeight method from + /// MachineBranchProbabilityInfo class. + uint32_t getSuccWeight(const_succ_iterator Succ) const; + + + // Methods used to maintain doubly linked list of blocks... friend struct ilist_traits; // Machine-CFG mutators - /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock. - /// Don't do this unless you know what you're doing, because it doesn't - /// update pred's successors list. Use pred->addSuccessor instead. - /// - void addPredecessor(MachineBasicBlock *pred); + /// Remove Pred as a predecessor of this MachineBasicBlock. Don't do this + /// unless you know what you're doing, because it doesn't update Pred's + /// successors list. Use Pred->addSuccessor instead. + void addPredecessor(MachineBasicBlock *Pred); - /// removePredecessor - Remove pred as a predecessor of this - /// MachineBasicBlock. Don't do this unless you know what you're - /// doing, because it doesn't update pred's successors list. Use - /// pred->removeSuccessor instead. - /// - void removePredecessor(MachineBasicBlock *pred); + /// Remove Pred as a predecessor of this MachineBasicBlock. Don't do this + /// unless you know what you're doing, because it doesn't update Pred's + /// successors list. Use Pred->removeSuccessor instead. + void removePredecessor(MachineBasicBlock *Pred); }; raw_ostream& operator<<(raw_ostream &OS, const MachineBasicBlock &MBB); -void WriteAsOperand(raw_ostream &, const MachineBasicBlock*, bool t); +// This is useful when building IndexedMaps keyed on basic block pointers. +struct MBB2NumberFunctor : + public std::unary_function { + unsigned operator()(const MachineBasicBlock *MBB) const { + return MBB->getNumber(); + } +}; //===--------------------------------------------------------------------===// // GraphTraits specializations for machine basic block graphs (machine-CFGs) //===--------------------------------------------------------------------===// // Provide specializations of GraphTraits to be able to treat a -// MachineFunction as a graph of MachineBasicBlocks... +// MachineFunction as a graph of MachineBasicBlocks. // template <> struct GraphTraits { @@ -411,7 +779,7 @@ template <> struct GraphTraits { }; // Provide specializations of GraphTraits to be able to treat a -// MachineFunction as a graph of MachineBasicBlocks... and to walk it +// MachineFunction as a graph of MachineBasicBlocks and to walk it // in inverse order. Inverse order for a function is considered // to be when traversing the predecessor edges of a MBB // instead of the successor edges. @@ -444,6 +812,31 @@ template <> struct GraphTraits > { } }; + + +/// MachineInstrSpan provides an interface to get an iteration range +/// containing the instruction it was initialized with, along with all +/// those instructions inserted prior to or following that instruction +/// at some point after the MachineInstrSpan is constructed. +class MachineInstrSpan { + MachineBasicBlock &MBB; + MachineBasicBlock::iterator I, B, E; +public: + MachineInstrSpan(MachineBasicBlock::iterator I) + : MBB(*I->getParent()), + I(I), + B(I == MBB.begin() ? MBB.end() : std::prev(I)), + E(std::next(I)) {} + + MachineBasicBlock::iterator begin() { + return B == MBB.end() ? MBB.begin() : std::next(B); + } + MachineBasicBlock::iterator end() { return E; } + bool empty() { return begin() == end(); } + + MachineBasicBlock::iterator getInitial() { return I; } +}; + } // End llvm namespace #endif