namespace llvm {
+class Pass;
class BasicBlock;
class MachineFunction;
+class MCSymbol;
+class StringRef;
+class raw_ostream;
template <>
struct ilist_traits<MachineInstr> : public ilist_default_traits<MachineInstr> {
private:
- mutable ilist_node<MachineInstr> Sentinel;
+ mutable ilist_half_node<MachineInstr> Sentinel;
// this is only set by the MachineBasicBlock owning the LiveList
friend class MachineBasicBlock;
/// exception handler.
bool IsLandingPad;
+ /// AddressTaken - Indicate that this basic block is potentially the
+ /// target of an indirect branch.
+ bool AddressTaken;
+
// Intrusive list support
MachineBasicBlock() {}
public:
/// getBasicBlock - Return the LLVM basic block that this instance
- /// corresponded to originally.
+ /// 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)".
+ StringRef getName() const;
+
+ /// hasAddressTaken - 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.
+ void setHasAddressTaken() { AddressTaken = true; }
+
/// getParent - Return the MachineFunction containing this basic block.
///
const MachineFunction *getParent() const { return xParent; }
// Iteration support for live in sets. These sets are kept in sorted
// order by their register number.
- typedef std::vector<unsigned>::iterator livein_iterator;
- typedef std::vector<unsigned>::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 std::vector<unsigned>::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(); }
/// getAlignment - Return alignment of the basic block.
/// 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.
+ void updateTerminator();
+
// Machine-CFG mutators
/// addSuccessor - Add succ as a successor of this MachineBasicBlock.
/// transferSuccessors - Transfers all the successors from MBB to this
/// machine basic block (i.e., copies all the successors fromMBB and
- /// remove all the successors fromBB).
+ /// remove all the successors from fromMBB).
void transferSuccessors(MachineBasicBlock *fromMBB);
+
+ /// transferSuccessorsAndUpdatePHIs - 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);
/// isSuccessor - Return true if the specified MBB is a successor of 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.
+ bool canFallThrough();
+
+ /// Returns a pointer to the first instructon in this block that is not a
+ /// PHINode instruction. When adding instruction 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();
+
/// getFirstTerminator - returns an iterator to the first terminator
/// instruction of this basic block. If a terminator does not exist,
/// it returns end()
iterator getFirstTerminator();
- /// 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;
+ /// SplitCriticalEdge - 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(); }
template<typename IT>
void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); }
iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); }
+ iterator insertAfter(iterator I, MachineInstr *M) {
+ return Insts.insertAfter(I, M);
+ }
// erase - Remove the specified element or range from the instruction list.
// These functions delete any instructions removed.
MachineBasicBlock *DestB,
bool isCond);
+ /// findDebugLoc - find the next valid DebugLoc starting at MBBI, skipping
+ /// any DBG_VALUE instructions. Return UnknownLoc if there is none.
+ DebugLoc findDebugLoc(MachineBasicBlock::iterator &MBBI);
+
// Debugging methods.
void dump() const;
- void print(std::ostream &OS) const;
- void print(std::ostream *OS) const { if (OS) print(*OS); }
+ void print(raw_ostream &OS) const;
/// getNumber - MachineBasicBlocks are uniquely numbered at the function
/// level, unless they're not in a MachineFunction yet, in which case this
int getNumber() const { return Number; }
void setNumber(int N) { Number = N; }
+ /// getSymbol - Return the MCSymbol for this basic block.
+ ///
+ MCSymbol *getSymbol() const;
+
private: // Methods used to maintain doubly linked list of blocks...
friend struct ilist_traits<MachineBasicBlock>;
void removePredecessor(MachineBasicBlock *pred);
};
-std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB);
+raw_ostream& operator<<(raw_ostream &OS, const MachineBasicBlock &MBB);
+
+void WriteAsOperand(raw_ostream &, const MachineBasicBlock*, bool t);
//===--------------------------------------------------------------------===//
// GraphTraits specializations for machine basic block graphs (machine-CFGs)
projects / oota-llvm.git / blobdiff