1 //===-- llvm/CodeGen/MachineFunction.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 native machine code for a function. This class contains a list of
11 // MachineBasicBlock instances that make up the current compiled function.
13 // This class also contains pointers to various classes which hold
14 // target-specific information about the generated code.
16 //===----------------------------------------------------------------------===//
18 #ifndef LLVM_CODEGEN_MACHINEFUNCTION_H
19 #define LLVM_CODEGEN_MACHINEFUNCTION_H
21 #include "llvm/CodeGen/MachineDebugInfo.h"
22 #include "llvm/CodeGen/MachineBasicBlock.h"
23 #include "llvm/Support/Annotation.h"
30 class MachineFrameInfo;
31 class MachineConstantPool;
32 class MachineJumpTableInfo;
36 struct ilist_traits<MachineBasicBlock> {
37 // this is only set by the MachineFunction owning the ilist
38 friend class MachineFunction;
39 MachineFunction* Parent;
42 ilist_traits<MachineBasicBlock>() : Parent(0) { }
44 static MachineBasicBlock* getPrev(MachineBasicBlock* N) { return N->Prev; }
45 static MachineBasicBlock* getNext(MachineBasicBlock* N) { return N->Next; }
47 static const MachineBasicBlock*
48 getPrev(const MachineBasicBlock* N) { return N->Prev; }
50 static const MachineBasicBlock*
51 getNext(const MachineBasicBlock* N) { return N->Next; }
53 static void setPrev(MachineBasicBlock* N, MachineBasicBlock* prev) {
56 static void setNext(MachineBasicBlock* N, MachineBasicBlock* next) {
60 static MachineBasicBlock* createSentinel();
61 static void destroySentinel(MachineBasicBlock *MBB) { delete MBB; }
62 void addNodeToList(MachineBasicBlock* N);
63 void removeNodeFromList(MachineBasicBlock* N);
64 void transferNodesFromList(iplist<MachineBasicBlock,
65 ilist_traits<MachineBasicBlock> > &toList,
66 ilist_iterator<MachineBasicBlock> first,
67 ilist_iterator<MachineBasicBlock> last);
70 /// MachineFunctionInfo - This class can be derived from and used by targets to
71 /// hold private target-specific information for each MachineFunction. Objects
72 /// of type are accessed/created with MF::getInfo and destroyed when the
73 /// MachineFunction is destroyed.
74 struct MachineFunctionInfo {
75 virtual ~MachineFunctionInfo() {};
78 class MachineFunction : private Annotation {
80 const TargetMachine &Target;
82 // List of machine basic blocks in function
83 ilist<MachineBasicBlock> BasicBlocks;
85 // Keeping track of mapping from SSA values to registers
86 SSARegMap *SSARegMapping;
88 // Used to keep track of target-specific per-machine function information for
89 // the target implementation.
90 MachineFunctionInfo *MFInfo;
92 // Keep track of objects allocated on the stack.
93 MachineFrameInfo *FrameInfo;
95 // Keep track of constants which are spilled to memory
96 MachineConstantPool *ConstantPool;
98 // Keep track of jump tables for switch instructions
99 MachineJumpTableInfo *JumpTableInfo;
101 // Function-level unique numbering for MachineBasicBlocks. When a
102 // MachineBasicBlock is inserted into a MachineFunction is it automatically
103 // numbered and this vector keeps track of the mapping from ID's to MBB's.
104 std::vector<MachineBasicBlock*> MBBNumbering;
106 /// UsedPhysRegs - This is a new[]'d array of bools that is computed and set
107 /// by the register allocator, and must be kept up to date by passes that run
108 /// after register allocation (though most don't modify this). This is used
109 /// so that the code generator knows which callee save registers to save and
110 /// for other target specific uses.
113 /// LiveIns/LiveOuts - Keep track of the physical registers that are
114 /// livein/liveout of the function. Live in values are typically arguments in
115 /// registers, live out values are typically return values in registers.
116 /// LiveIn values are allowed to have virtual registers associated with them,
117 /// stored in the second element.
118 std::vector<std::pair<unsigned, unsigned> > LiveIns;
119 std::vector<unsigned> LiveOuts;
122 MachineFunction(const Function *Fn, const TargetMachine &TM);
125 /// getFunction - Return the LLVM function that this machine code represents
127 const Function *getFunction() const { return Fn; }
129 /// getTarget - Return the target machine this machine code is compiled with
131 const TargetMachine &getTarget() const { return Target; }
133 /// SSARegMap Interface... Keep track of information about each SSA virtual
134 /// register, such as which register class it belongs to.
136 SSARegMap *getSSARegMap() const { return SSARegMapping; }
137 void clearSSARegMap();
139 /// getFrameInfo - Return the frame info object for the current function.
140 /// This object contains information about objects allocated on the stack
141 /// frame of the current function in an abstract way.
143 MachineFrameInfo *getFrameInfo() const { return FrameInfo; }
145 /// getJumpTableInfo - Return the jump table info object for the current
146 /// function. This object contains information about jump tables for switch
147 /// instructions in the current function.
149 MachineJumpTableInfo *getJumpTableInfo() const { return JumpTableInfo; }
151 /// getConstantPool - Return the constant pool object for the current
154 MachineConstantPool *getConstantPool() const { return ConstantPool; }
156 /// MachineFunctionInfo - Keep track of various per-function pieces of
157 /// information for backends that would like to do so.
159 template<typename Ty>
161 if (!MFInfo) MFInfo = new Ty(*this);
163 assert((void*)dynamic_cast<Ty*>(MFInfo) == (void*)MFInfo &&
164 "Invalid concrete type or multiple inheritence for getInfo");
165 return static_cast<Ty*>(MFInfo);
168 template<typename Ty>
169 const Ty *getInfo() const {
170 return const_cast<MachineFunction*>(this)->getInfo<Ty>();
173 /// setUsedPhysRegs - The register allocator should call this to initialized
174 /// the UsedPhysRegs set. This should be passed a new[]'d array with entries
175 /// for all of the physical registers that the target supports. Each array
176 /// entry should be set to true iff the physical register is used within the
178 void setUsedPhysRegs(bool *UPR) { UsedPhysRegs = UPR; }
180 /// getUsedPhysregs - This returns the UsedPhysRegs array. This returns null
181 /// before register allocation.
182 bool *getUsedPhysregs() { return UsedPhysRegs; }
183 const bool *getUsedPhysregs() const { return UsedPhysRegs; }
185 /// isPhysRegUsed - Return true if the specified register is used in this
186 /// function. This only works after register allocation.
187 bool isPhysRegUsed(unsigned Reg) { return UsedPhysRegs[Reg]; }
189 /// changePhyRegUsed - This method allows code that runs after register
190 /// allocation to keep the PhysRegsUsed array up-to-date.
191 void changePhyRegUsed(unsigned Reg, bool State) { UsedPhysRegs[Reg] = State; }
194 // LiveIn/LiveOut management methods.
196 /// addLiveIn/Out - Add the specified register as a live in/out. Note that it
197 /// is an error to add the same register to the same set more than once.
198 void addLiveIn(unsigned Reg, unsigned vreg = 0) {
199 LiveIns.push_back(std::make_pair(Reg, vreg));
201 void addLiveOut(unsigned Reg) { LiveOuts.push_back(Reg); }
203 // Iteration support for live in/out sets. These sets are kept in sorted
204 // order by their register number.
205 typedef std::vector<std::pair<unsigned,unsigned> >::const_iterator
207 typedef std::vector<unsigned>::const_iterator liveout_iterator;
208 livein_iterator livein_begin() const { return LiveIns.begin(); }
209 livein_iterator livein_end() const { return LiveIns.end(); }
210 bool livein_empty() const { return LiveIns.empty(); }
211 liveout_iterator liveout_begin() const { return LiveOuts.begin(); }
212 liveout_iterator liveout_end() const { return LiveOuts.end(); }
213 bool liveout_empty() const { return LiveOuts.empty(); }
215 /// getBlockNumbered - MachineBasicBlocks are automatically numbered when they
216 /// are inserted into the machine function. The block number for a machine
217 /// basic block can be found by using the MBB::getBlockNumber method, this
218 /// method provides the inverse mapping.
220 MachineBasicBlock *getBlockNumbered(unsigned N) {
221 assert(N < MBBNumbering.size() && "Illegal block number");
222 assert(MBBNumbering[N] && "Block was removed from the machine function!");
223 return MBBNumbering[N];
226 /// getLastBlock - Returns the MachineBasicBlock with the greatest number
227 MachineBasicBlock *getLastBlock() {
228 return MBBNumbering.back();
230 const MachineBasicBlock *getLastBlock() const {
231 return MBBNumbering.back();
234 /// print - Print out the MachineFunction in a format suitable for debugging
235 /// to the specified stream.
237 void print(std::ostream &OS) const;
239 /// viewCFG - This function is meant for use from the debugger. You can just
240 /// say 'call F->viewCFG()' and a ghostview window should pop up from the
241 /// program, displaying the CFG of the current function with the code for each
242 /// basic block inside. This depends on there being a 'dot' and 'gv' program
245 void viewCFG() const;
247 /// viewCFGOnly - This function is meant for use from the debugger. It works
248 /// just like viewCFG, but it does not include the contents of basic blocks
249 /// into the nodes, just the label. If you are only interested in the CFG
250 /// this can make the graph smaller.
252 void viewCFGOnly() const;
254 /// dump - Print the current MachineFunction to cerr, useful for debugger use.
258 /// construct - Allocate and initialize a MachineFunction for a given Function
261 static MachineFunction& construct(const Function *F, const TargetMachine &TM);
263 /// destruct - Destroy the MachineFunction corresponding to a given Function
265 static void destruct(const Function *F);
267 /// get - Return a handle to a MachineFunction corresponding to the given
268 /// Function. This should not be called before "construct()" for a given
271 static MachineFunction& get(const Function *F);
273 // Provide accessors for the MachineBasicBlock list...
274 typedef ilist<MachineBasicBlock> BasicBlockListType;
275 typedef BasicBlockListType::iterator iterator;
276 typedef BasicBlockListType::const_iterator const_iterator;
277 typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
278 typedef std::reverse_iterator<iterator> reverse_iterator;
280 // Provide accessors for basic blocks...
281 const BasicBlockListType &getBasicBlockList() const { return BasicBlocks; }
282 BasicBlockListType &getBasicBlockList() { return BasicBlocks; }
284 //===--------------------------------------------------------------------===//
285 // BasicBlock iterator forwarding functions
287 iterator begin() { return BasicBlocks.begin(); }
288 const_iterator begin() const { return BasicBlocks.begin(); }
289 iterator end () { return BasicBlocks.end(); }
290 const_iterator end () const { return BasicBlocks.end(); }
292 reverse_iterator rbegin() { return BasicBlocks.rbegin(); }
293 const_reverse_iterator rbegin() const { return BasicBlocks.rbegin(); }
294 reverse_iterator rend () { return BasicBlocks.rend(); }
295 const_reverse_iterator rend () const { return BasicBlocks.rend(); }
297 unsigned size() const { return BasicBlocks.size(); }
298 bool empty() const { return BasicBlocks.empty(); }
299 const MachineBasicBlock &front() const { return BasicBlocks.front(); }
300 MachineBasicBlock &front() { return BasicBlocks.front(); }
301 const MachineBasicBlock & back() const { return BasicBlocks.back(); }
302 MachineBasicBlock & back() { return BasicBlocks.back(); }
304 //===--------------------------------------------------------------------===//
305 // Internal functions used to automatically number MachineBasicBlocks
308 /// getNextMBBNumber - Returns the next unique number to be assigned
309 /// to a MachineBasicBlock in this MachineFunction.
311 unsigned addToMBBNumbering(MachineBasicBlock *MBB) {
312 MBBNumbering.push_back(MBB);
313 return MBBNumbering.size()-1;
316 /// removeFromMBBNumbering - Remove the specific machine basic block from our
317 /// tracker, this is only really to be used by the MachineBasicBlock
319 void removeFromMBBNumbering(unsigned N) {
320 assert(N < MBBNumbering.size() && "Illegal basic block #");
325 //===--------------------------------------------------------------------===//
326 // GraphTraits specializations for function basic block graphs (CFGs)
327 //===--------------------------------------------------------------------===//
329 // Provide specializations of GraphTraits to be able to treat a
330 // machine function as a graph of machine basic blocks... these are
331 // the same as the machine basic block iterators, except that the root
332 // node is implicitly the first node of the function.
334 template <> struct GraphTraits<MachineFunction*> :
335 public GraphTraits<MachineBasicBlock*> {
336 static NodeType *getEntryNode(MachineFunction *F) {
340 // nodes_iterator/begin/end - Allow iteration over all nodes in the graph
341 typedef MachineFunction::iterator nodes_iterator;
342 static nodes_iterator nodes_begin(MachineFunction *F) { return F->begin(); }
343 static nodes_iterator nodes_end (MachineFunction *F) { return F->end(); }
345 template <> struct GraphTraits<const MachineFunction*> :
346 public GraphTraits<const MachineBasicBlock*> {
347 static NodeType *getEntryNode(const MachineFunction *F) {
351 // nodes_iterator/begin/end - Allow iteration over all nodes in the graph
352 typedef MachineFunction::const_iterator nodes_iterator;
353 static nodes_iterator nodes_begin(const MachineFunction *F) { return F->begin(); }
354 static nodes_iterator nodes_end (const MachineFunction *F) { return F->end(); }
358 // Provide specializations of GraphTraits to be able to treat a function as a
359 // graph of basic blocks... and to walk it in inverse order. Inverse order for
360 // a function is considered to be when traversing the predecessor edges of a BB
361 // instead of the successor edges.
363 template <> struct GraphTraits<Inverse<MachineFunction*> > :
364 public GraphTraits<Inverse<MachineBasicBlock*> > {
365 static NodeType *getEntryNode(Inverse<MachineFunction*> G) {
366 return &G.Graph->front();
369 template <> struct GraphTraits<Inverse<const MachineFunction*> > :
370 public GraphTraits<Inverse<const MachineBasicBlock*> > {
371 static NodeType *getEntryNode(Inverse<const MachineFunction *> G) {
372 return &G.Graph->front();
376 } // End llvm namespace