1 //===-- llvm/CodeGen/MachineBasicBlock.h ------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Collect the sequence of machine instructions for a basic block.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CODEGEN_MACHINEBASICBLOCK_H
15 #define LLVM_CODEGEN_MACHINEBASICBLOCK_H
17 #include "llvm/CodeGen/MachineInstr.h"
18 #include "llvm/ADT/GraphTraits.h"
19 #include "llvm/ADT/ilist"
20 #include "llvm/Support/Streams.h"
23 class MachineFunction;
27 struct ilist_traits<MachineInstr> {
29 // this is only set by the MachineBasicBlock owning the ilist
30 friend class MachineBasicBlock;
31 MachineBasicBlock* parent;
34 ilist_traits<MachineInstr>() : parent(0) { }
36 static MachineInstr* getPrev(MachineInstr* N) { return N->prev; }
37 static MachineInstr* getNext(MachineInstr* N) { return N->next; }
39 static const MachineInstr*
40 getPrev(const MachineInstr* N) { return N->prev; }
42 static const MachineInstr*
43 getNext(const MachineInstr* N) { return N->next; }
45 static void setPrev(MachineInstr* N, MachineInstr* prev) { N->prev = prev; }
46 static void setNext(MachineInstr* N, MachineInstr* next) { N->next = next; }
48 static MachineInstr* createSentinel();
49 static void destroySentinel(MachineInstr *MI) { delete MI; }
50 void addNodeToList(MachineInstr* N);
51 void removeNodeFromList(MachineInstr* N);
52 void transferNodesFromList(
53 iplist<MachineInstr, ilist_traits<MachineInstr> >& toList,
54 ilist_iterator<MachineInstr> first,
55 ilist_iterator<MachineInstr> last);
60 class MachineBasicBlock {
62 typedef ilist<MachineInstr> Instructions;
64 MachineBasicBlock *Prev, *Next;
66 std::vector<MachineBasicBlock *> Predecessors;
67 std::vector<MachineBasicBlock *> Successors;
69 MachineFunction *Parent;
72 MachineBasicBlock(const BasicBlock *bb = 0) : Prev(0), Next(0), BB(bb),
73 Number(-1), Parent(0) {
79 /// getBasicBlock - Return the LLVM basic block that this instance
80 /// corresponded to originally.
82 const BasicBlock *getBasicBlock() const { return BB; }
84 /// getParent - Return the MachineFunction containing this basic block.
86 const MachineFunction *getParent() const { return Parent; }
87 MachineFunction *getParent() { return Parent; }
89 typedef ilist<MachineInstr>::iterator iterator;
90 typedef ilist<MachineInstr>::const_iterator const_iterator;
91 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
92 typedef std::reverse_iterator<iterator> reverse_iterator;
94 unsigned size() const { return Insts.size(); }
95 bool empty() const { return Insts.empty(); }
97 MachineInstr& front() { return Insts.front(); }
98 MachineInstr& back() { return Insts.back(); }
100 iterator begin() { return Insts.begin(); }
101 const_iterator begin() const { return Insts.begin(); }
102 iterator end() { return Insts.end(); }
103 const_iterator end() const { return Insts.end(); }
104 reverse_iterator rbegin() { return Insts.rbegin(); }
105 const_reverse_iterator rbegin() const { return Insts.rbegin(); }
106 reverse_iterator rend () { return Insts.rend(); }
107 const_reverse_iterator rend () const { return Insts.rend(); }
109 // Machine-CFG iterators
110 typedef std::vector<MachineBasicBlock *>::iterator pred_iterator;
111 typedef std::vector<MachineBasicBlock *>::const_iterator const_pred_iterator;
112 typedef std::vector<MachineBasicBlock *>::iterator succ_iterator;
113 typedef std::vector<MachineBasicBlock *>::const_iterator const_succ_iterator;
115 pred_iterator pred_begin() { return Predecessors.begin(); }
116 const_pred_iterator pred_begin() const { return Predecessors.begin(); }
117 pred_iterator pred_end() { return Predecessors.end(); }
118 const_pred_iterator pred_end() const { return Predecessors.end(); }
119 unsigned pred_size() const { return Predecessors.size(); }
120 bool pred_empty() const { return Predecessors.empty(); }
121 succ_iterator succ_begin() { return Successors.begin(); }
122 const_succ_iterator succ_begin() const { return Successors.begin(); }
123 succ_iterator succ_end() { return Successors.end(); }
124 const_succ_iterator succ_end() const { return Successors.end(); }
125 unsigned succ_size() const { return Successors.size(); }
126 bool succ_empty() const { return Successors.empty(); }
128 // Code Layout methods.
130 /// moveBefore/moveAfter - move 'this' block before or after the specified
131 /// block. This only moves the block, it does not modify the CFG or adjust
132 /// potential fall-throughs at the end of the block.
133 void moveBefore(MachineBasicBlock *NewAfter);
134 void moveAfter(MachineBasicBlock *NewBefore);
136 // Machine-CFG mutators
138 /// addSuccessor - Add succ as a successor of this MachineBasicBlock.
139 /// The Predecessors list of succ is automatically updated.
141 void addSuccessor(MachineBasicBlock *succ);
143 /// removeSuccessor - Remove successor from the successors list of this
144 /// MachineBasicBlock. The Predecessors list of succ is automatically updated.
146 void removeSuccessor(MachineBasicBlock *succ);
148 /// removeSuccessor - Remove specified successor from the successors list of
149 /// this MachineBasicBlock. The Predecessors list of succ is automatically
152 void removeSuccessor(succ_iterator I);
154 /// isSuccessor - Return true if the specified MBB is a successor of this
156 bool isSuccessor(MachineBasicBlock *MBB) const {
157 for (const_succ_iterator I = succ_begin(), E = succ_end(); I != E; ++I)
163 /// getFirstTerminator - returns an iterator to the first terminator
164 /// instruction of this basic block. If a terminator does not exist,
166 iterator getFirstTerminator();
168 void pop_front() { Insts.pop_front(); }
169 void pop_back() { Insts.pop_back(); }
170 void push_back(MachineInstr *MI) { Insts.push_back(MI); }
171 template<typename IT>
172 void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); }
173 iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); }
175 // erase - Remove the specified element or range from the instruction list.
176 // These functions delete any instructions removed.
178 iterator erase(iterator I) { return Insts.erase(I); }
179 iterator erase(iterator I, iterator E) { return Insts.erase(I, E); }
180 MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); }
181 void clear() { Insts.clear(); }
183 /// splice - Take a block of instructions from MBB 'Other' in the range [From,
184 /// To), and insert them into this MBB right before 'where'.
185 void splice(iterator where, MachineBasicBlock *Other, iterator From,
187 Insts.splice(where, Other->Insts, From, To);
190 // Debugging methods.
192 void print(OStream &OS) const {
193 if (OS.stream()) print(*OS.stream());
195 void print(std::ostream &OS) const;
197 /// getNumber - MachineBasicBlocks are uniquely numbered at the function
198 /// level, unless they're not in a MachineFunction yet, in which case this
201 int getNumber() const { return Number; }
202 void setNumber(int N) { Number = N; }
204 private: // Methods used to maintain doubly linked list of blocks...
205 friend struct ilist_traits<MachineBasicBlock>;
207 MachineBasicBlock *getPrev() const { return Prev; }
208 MachineBasicBlock *getNext() const { return Next; }
209 void setPrev(MachineBasicBlock *P) { Prev = P; }
210 void setNext(MachineBasicBlock *N) { Next = N; }
212 // Machine-CFG mutators
214 /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock.
215 /// Don't do this unless you know what you're doing, because it doesn't
216 /// update pred's successors list. Use pred->addSuccessor instead.
218 void addPredecessor(MachineBasicBlock *pred);
220 /// removePredecessor - Remove pred as a predecessor of this
221 /// MachineBasicBlock. Don't do this unless you know what you're
222 /// doing, because it doesn't update pred's successors list. Use
223 /// pred->removeSuccessor instead.
225 void removePredecessor(MachineBasicBlock *pred);
228 std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB);
229 OStream& operator<<(OStream &OS, const MachineBasicBlock &MBB);
231 //===--------------------------------------------------------------------===//
232 // GraphTraits specializations for machine basic block graphs (machine-CFGs)
233 //===--------------------------------------------------------------------===//
235 // Provide specializations of GraphTraits to be able to treat a
236 // MachineFunction as a graph of MachineBasicBlocks...
239 template <> struct GraphTraits<MachineBasicBlock *> {
240 typedef MachineBasicBlock NodeType;
241 typedef MachineBasicBlock::succ_iterator ChildIteratorType;
243 static NodeType *getEntryNode(MachineBasicBlock *BB) { return BB; }
244 static inline ChildIteratorType child_begin(NodeType *N) {
245 return N->succ_begin();
247 static inline ChildIteratorType child_end(NodeType *N) {
248 return N->succ_end();
252 template <> struct GraphTraits<const MachineBasicBlock *> {
253 typedef const MachineBasicBlock NodeType;
254 typedef MachineBasicBlock::const_succ_iterator ChildIteratorType;
256 static NodeType *getEntryNode(const MachineBasicBlock *BB) { return BB; }
257 static inline ChildIteratorType child_begin(NodeType *N) {
258 return N->succ_begin();
260 static inline ChildIteratorType child_end(NodeType *N) {
261 return N->succ_end();
265 // Provide specializations of GraphTraits to be able to treat a
266 // MachineFunction as a graph of MachineBasicBlocks... and to walk it
267 // in inverse order. Inverse order for a function is considered
268 // to be when traversing the predecessor edges of a MBB
269 // instead of the successor edges.
271 template <> struct GraphTraits<Inverse<MachineBasicBlock*> > {
272 typedef MachineBasicBlock NodeType;
273 typedef MachineBasicBlock::pred_iterator ChildIteratorType;
274 static NodeType *getEntryNode(Inverse<MachineBasicBlock *> G) {
277 static inline ChildIteratorType child_begin(NodeType *N) {
278 return N->pred_begin();
280 static inline ChildIteratorType child_end(NodeType *N) {
281 return N->pred_end();
285 template <> struct GraphTraits<Inverse<const MachineBasicBlock*> > {
286 typedef const MachineBasicBlock NodeType;
287 typedef MachineBasicBlock::const_pred_iterator ChildIteratorType;
288 static NodeType *getEntryNode(Inverse<const MachineBasicBlock*> G) {
291 static inline ChildIteratorType child_begin(NodeType *N) {
292 return N->pred_begin();
294 static inline ChildIteratorType child_end(NodeType *N) {
295 return N->pred_end();
299 } // End llvm namespace