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 {
61 typedef ilist<MachineInstr> Instructions;
63 MachineBasicBlock *Prev, *Next;
66 MachineFunction *Parent;
68 /// Predecessors/Successors - Keep track of the predecessor / successor
70 std::vector<MachineBasicBlock *> Predecessors;
71 std::vector<MachineBasicBlock *> Successors;
73 /// LiveIns - Keep track of the physical registers that are livein of
75 std::vector<unsigned> LiveIns;
77 /// IsLandingPad - Indicate that this basic block is entered via an
78 /// exception handler.
82 explicit MachineBasicBlock(const BasicBlock *bb = 0) : Prev(0), Next(0),
91 /// getBasicBlock - Return the LLVM basic block that this instance
92 /// corresponded to originally.
94 const BasicBlock *getBasicBlock() const { return BB; }
96 /// getParent - Return the MachineFunction containing this basic block.
98 const MachineFunction *getParent() const { return Parent; }
99 MachineFunction *getParent() { return Parent; }
101 typedef ilist<MachineInstr>::iterator iterator;
102 typedef ilist<MachineInstr>::const_iterator const_iterator;
103 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
104 typedef std::reverse_iterator<iterator> reverse_iterator;
106 unsigned size() const { return Insts.size(); }
107 bool empty() const { return Insts.empty(); }
109 MachineInstr& front() { return Insts.front(); }
110 MachineInstr& back() { return Insts.back(); }
112 iterator begin() { return Insts.begin(); }
113 const_iterator begin() const { return Insts.begin(); }
114 iterator end() { return Insts.end(); }
115 const_iterator end() const { return Insts.end(); }
116 reverse_iterator rbegin() { return Insts.rbegin(); }
117 const_reverse_iterator rbegin() const { return Insts.rbegin(); }
118 reverse_iterator rend () { return Insts.rend(); }
119 const_reverse_iterator rend () const { return Insts.rend(); }
121 // Machine-CFG iterators
122 typedef std::vector<MachineBasicBlock *>::iterator pred_iterator;
123 typedef std::vector<MachineBasicBlock *>::const_iterator const_pred_iterator;
124 typedef std::vector<MachineBasicBlock *>::iterator succ_iterator;
125 typedef std::vector<MachineBasicBlock *>::const_iterator const_succ_iterator;
127 pred_iterator pred_begin() { return Predecessors.begin(); }
128 const_pred_iterator pred_begin() const { return Predecessors.begin(); }
129 pred_iterator pred_end() { return Predecessors.end(); }
130 const_pred_iterator pred_end() const { return Predecessors.end(); }
131 unsigned pred_size() const { return Predecessors.size(); }
132 bool pred_empty() const { return Predecessors.empty(); }
133 succ_iterator succ_begin() { return Successors.begin(); }
134 const_succ_iterator succ_begin() const { return Successors.begin(); }
135 succ_iterator succ_end() { return Successors.end(); }
136 const_succ_iterator succ_end() const { return Successors.end(); }
137 unsigned succ_size() const { return Successors.size(); }
138 bool succ_empty() const { return Successors.empty(); }
140 // LiveIn management methods.
142 /// addLiveIn - Add the specified register as a live in. Note that it
143 /// is an error to add the same register to the same set more than once.
144 void addLiveIn(unsigned Reg) { LiveIns.push_back(Reg); }
146 /// removeLiveIn - Remove the specified register from the live in set.
148 void removeLiveIn(unsigned Reg);
150 // Iteration support for live in sets. These sets are kept in sorted
151 // order by their register number.
152 typedef std::vector<unsigned>::iterator livein_iterator;
153 typedef std::vector<unsigned>::const_iterator const_livein_iterator;
154 livein_iterator livein_begin() { return LiveIns.begin(); }
155 const_livein_iterator livein_begin() const { return LiveIns.begin(); }
156 livein_iterator livein_end() { return LiveIns.end(); }
157 const_livein_iterator livein_end() const { return LiveIns.end(); }
158 bool livein_empty() const { return LiveIns.empty(); }
160 /// isLandingPad - Returns true if the block is a landing pad. That is
161 /// this basic block is entered via an exception handler.
162 bool isLandingPad() const { return IsLandingPad; }
164 /// setIsLandingPad - Indicates the block is a landing pad. That is
165 /// this basic block is entered via an exception handler.
166 void setIsLandingPad() { IsLandingPad = true; }
168 // Code Layout methods.
170 /// moveBefore/moveAfter - move 'this' block before or after the specified
171 /// block. This only moves the block, it does not modify the CFG or adjust
172 /// potential fall-throughs at the end of the block.
173 void moveBefore(MachineBasicBlock *NewAfter);
174 void moveAfter(MachineBasicBlock *NewBefore);
176 // Machine-CFG mutators
178 /// addSuccessor - Add succ as a successor of this MachineBasicBlock.
179 /// The Predecessors list of succ is automatically updated.
181 void addSuccessor(MachineBasicBlock *succ);
183 /// removeSuccessor - Remove successor from the successors list of this
184 /// MachineBasicBlock. The Predecessors list of succ is automatically updated.
186 void removeSuccessor(MachineBasicBlock *succ);
188 /// removeSuccessor - Remove specified successor from the successors list of
189 /// this MachineBasicBlock. The Predecessors list of succ is automatically
192 void removeSuccessor(succ_iterator I);
194 /// isSuccessor - Return true if the specified MBB is a successor of this
196 bool isSuccessor(MachineBasicBlock *MBB) const {
197 for (const_succ_iterator I = succ_begin(), E = succ_end(); I != E; ++I)
203 /// getFirstTerminator - returns an iterator to the first terminator
204 /// instruction of this basic block. If a terminator does not exist,
206 iterator getFirstTerminator();
208 void pop_front() { Insts.pop_front(); }
209 void pop_back() { Insts.pop_back(); }
210 void push_back(MachineInstr *MI) { Insts.push_back(MI); }
211 template<typename IT>
212 void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); }
213 iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); }
215 // erase - Remove the specified element or range from the instruction list.
216 // These functions delete any instructions removed.
218 iterator erase(iterator I) { return Insts.erase(I); }
219 iterator erase(iterator I, iterator E) { return Insts.erase(I, E); }
220 MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); }
221 void clear() { Insts.clear(); }
223 /// splice - Take a block of instructions from MBB 'Other' in the range [From,
224 /// To), and insert them into this MBB right before 'where'.
225 void splice(iterator where, MachineBasicBlock *Other, iterator From,
227 Insts.splice(where, Other->Insts, From, To);
230 // Debugging methods.
232 void print(std::ostream &OS) const;
233 void print(std::ostream *OS) const { if (OS) print(*OS); }
235 /// getNumber - MachineBasicBlocks are uniquely numbered at the function
236 /// level, unless they're not in a MachineFunction yet, in which case this
239 int getNumber() const { return Number; }
240 void setNumber(int N) { Number = N; }
242 private: // Methods used to maintain doubly linked list of blocks...
243 friend struct ilist_traits<MachineBasicBlock>;
245 MachineBasicBlock *getPrev() const { return Prev; }
246 MachineBasicBlock *getNext() const { return Next; }
247 void setPrev(MachineBasicBlock *P) { Prev = P; }
248 void setNext(MachineBasicBlock *N) { Next = N; }
250 // Machine-CFG mutators
252 /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock.
253 /// Don't do this unless you know what you're doing, because it doesn't
254 /// update pred's successors list. Use pred->addSuccessor instead.
256 void addPredecessor(MachineBasicBlock *pred);
258 /// removePredecessor - Remove pred as a predecessor of this
259 /// MachineBasicBlock. Don't do this unless you know what you're
260 /// doing, because it doesn't update pred's successors list. Use
261 /// pred->removeSuccessor instead.
263 void removePredecessor(MachineBasicBlock *pred);
266 std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB);
268 //===--------------------------------------------------------------------===//
269 // GraphTraits specializations for machine basic block graphs (machine-CFGs)
270 //===--------------------------------------------------------------------===//
272 // Provide specializations of GraphTraits to be able to treat a
273 // MachineFunction as a graph of MachineBasicBlocks...
276 template <> struct GraphTraits<MachineBasicBlock *> {
277 typedef MachineBasicBlock NodeType;
278 typedef MachineBasicBlock::succ_iterator ChildIteratorType;
280 static NodeType *getEntryNode(MachineBasicBlock *BB) { return BB; }
281 static inline ChildIteratorType child_begin(NodeType *N) {
282 return N->succ_begin();
284 static inline ChildIteratorType child_end(NodeType *N) {
285 return N->succ_end();
289 template <> struct GraphTraits<const MachineBasicBlock *> {
290 typedef const MachineBasicBlock NodeType;
291 typedef MachineBasicBlock::const_succ_iterator ChildIteratorType;
293 static NodeType *getEntryNode(const MachineBasicBlock *BB) { return BB; }
294 static inline ChildIteratorType child_begin(NodeType *N) {
295 return N->succ_begin();
297 static inline ChildIteratorType child_end(NodeType *N) {
298 return N->succ_end();
302 // Provide specializations of GraphTraits to be able to treat a
303 // MachineFunction as a graph of MachineBasicBlocks... and to walk it
304 // in inverse order. Inverse order for a function is considered
305 // to be when traversing the predecessor edges of a MBB
306 // instead of the successor edges.
308 template <> struct GraphTraits<Inverse<MachineBasicBlock*> > {
309 typedef MachineBasicBlock NodeType;
310 typedef MachineBasicBlock::pred_iterator ChildIteratorType;
311 static NodeType *getEntryNode(Inverse<MachineBasicBlock *> G) {
314 static inline ChildIteratorType child_begin(NodeType *N) {
315 return N->pred_begin();
317 static inline ChildIteratorType child_end(NodeType *N) {
318 return N->pred_end();
322 template <> struct GraphTraits<Inverse<const MachineBasicBlock*> > {
323 typedef const MachineBasicBlock NodeType;
324 typedef MachineBasicBlock::const_pred_iterator ChildIteratorType;
325 static NodeType *getEntryNode(Inverse<const MachineBasicBlock*> G) {
328 static inline ChildIteratorType child_begin(NodeType *N) {
329 return N->pred_begin();
331 static inline ChildIteratorType child_end(NodeType *N) {
332 return N->pred_end();
336 } // End llvm namespace