#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/ilist"
-#include "llvm/Support/Streams.h"
namespace llvm {
- class MachineFunction;
-// ilist_traits
+class BasicBlock;
+class MachineFunction;
+class raw_ostream;
+
template <>
-struct ilist_traits<MachineInstr> {
-protected:
- // this is only set by the MachineBasicBlock owning the ilist
+struct ilist_traits<MachineInstr> : public ilist_default_traits<MachineInstr> {
+private:
+ mutable ilist_half_node<MachineInstr> Sentinel;
+
+ // this is only set by the MachineBasicBlock owning the LiveList
friend class MachineBasicBlock;
- MachineBasicBlock* parent;
+ MachineBasicBlock* Parent;
public:
- ilist_traits<MachineInstr>() : parent(0) { }
-
- static MachineInstr* getPrev(MachineInstr* N) { return N->Prev; }
- static MachineInstr* getNext(MachineInstr* N) { return N->Next; }
-
- static const MachineInstr*
- getPrev(const MachineInstr* N) { return N->Prev; }
-
- static const MachineInstr*
- getNext(const MachineInstr* N) { return N->Next; }
+ MachineInstr *createSentinel() const {
+ return static_cast<MachineInstr*>(&Sentinel);
+ }
+ void destroySentinel(MachineInstr *) const {}
- static void setPrev(MachineInstr* N, MachineInstr* prev) { N->Prev = prev; }
- static void setNext(MachineInstr* N, MachineInstr* next) { N->Next = next; }
+ MachineInstr *provideInitialHead() const { return createSentinel(); }
+ MachineInstr *ensureHead(MachineInstr*) const { return createSentinel(); }
+ static void noteHead(MachineInstr*, MachineInstr*) {}
- static MachineInstr* createSentinel();
- static void destroySentinel(MachineInstr *MI) { delete MI; }
void addNodeToList(MachineInstr* N);
void removeNodeFromList(MachineInstr* N);
- void transferNodesFromList(
- iplist<MachineInstr, ilist_traits<MachineInstr> >& toList,
- ilist_iterator<MachineInstr> first,
- ilist_iterator<MachineInstr> last);
+ void transferNodesFromList(ilist_traits &SrcTraits,
+ ilist_iterator<MachineInstr> first,
+ ilist_iterator<MachineInstr> last);
+ void deleteNode(MachineInstr *N);
+private:
+ void createNode(const MachineInstr &);
};
-class BasicBlock;
-
-class MachineBasicBlock {
+class MachineBasicBlock : public ilist_node<MachineBasicBlock> {
typedef ilist<MachineInstr> Instructions;
Instructions Insts;
- MachineBasicBlock *Prev, *Next;
const BasicBlock *BB;
int Number;
MachineFunction *xParent;
- void setParent(MachineFunction *P) { xParent = P; }
-
/// Predecessors/Successors - Keep track of the predecessor / successor
/// basicblocks.
std::vector<MachineBasicBlock *> Predecessors;
/// exception handler.
bool IsLandingPad;
-public:
- explicit MachineBasicBlock(const BasicBlock *bb = 0)
- : Prev(0), Next(0), BB(bb), Number(-1), xParent(0),
- Alignment(0), IsLandingPad(false) {
- Insts.parent = this;
- }
+ /// AddressTaken - Indicate that this basic block is potentially the
+ /// target of an indirect branch.
+ bool AddressTaken;
+
+ // Intrusive list support
+ MachineBasicBlock() {}
+
+ explicit MachineBasicBlock(MachineFunction &mf, const BasicBlock *bb);
~MachineBasicBlock();
+ // MachineBasicBlocks are allocated and owned by MachineFunction.
+ friend class MachineFunction;
+
+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; }
MachineFunction *getParent() { return xParent; }
- typedef ilist<MachineInstr>::iterator iterator;
- typedef ilist<MachineInstr>::const_iterator const_iterator;
+ typedef Instructions::iterator iterator;
+ typedef Instructions::const_iterator const_iterator;
typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
typedef std::reverse_iterator<iterator> reverse_iterator;
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(); }
/// 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);
/// isSuccessor - Return true if the specified MBB is a successor of this
/// block.
- bool isSuccessor(MachineBasicBlock *MBB) const;
+ 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.
+ 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();
/// 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;
+
void pop_front() { Insts.pop_front(); }
void pop_back() { Insts.pop_back(); }
void push_back(MachineInstr *MI) { Insts.push_back(MI); }
MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); }
void clear() { Insts.clear(); }
+ /// 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);
+ }
+
/// 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,
Insts.splice(where, Other->Insts, From, To);
}
+ /// removeFromParent - 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.
+ void eraseFromParent();
+
/// ReplaceUsesOfBlockWith - 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);
MachineBasicBlock *DestB,
bool isCond);
+ /// findDebugLoc - find the next valid DebugLoc starting at MBBI, skipping
+ /// any DEBUG_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
private: // Methods used to maintain doubly linked list of blocks...
friend struct ilist_traits<MachineBasicBlock>;
- MachineBasicBlock *getPrev() const { return Prev; }
- MachineBasicBlock *getNext() const { return Next; }
- void setPrev(MachineBasicBlock *P) { Prev = P; }
- void setNext(MachineBasicBlock *N) { Next = N; }
-
// Machine-CFG mutators
/// addPredecessor - Remove pred as a predecessor of this 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)