1 //===- DSSupport.h - Support for datastructure graphs -----------*- C++ -*-===//
3 // Support for graph nodes, call sites, and types.
5 //===----------------------------------------------------------------------===//
7 #ifndef LLVM_ANALYSIS_DSSUPPORT_H
8 #define LLVM_ANALYSIS_DSSUPPORT_H
14 #include "Support/hash_set"
22 class DSNode; // Each node in the graph
23 class DSGraph; // A graph for a function
25 namespace DS { // FIXME: After the paper, this should get cleaned up
26 enum { PointerShift = 3, // 64bit ptrs = 3, 32 bit ptrs = 2
27 PointerSize = 1 << PointerShift
30 // isPointerType - Return true if this first class type is big enough to hold
33 bool isPointerType(const Type *Ty);
36 //===----------------------------------------------------------------------===//
37 /// DSNodeHandle - Implement a "handle" to a data structure node that takes care
38 /// of all of the add/un'refing of the node to prevent the backpointers in the
39 /// graph from getting out of date. This class represents a "pointer" in the
40 /// graph, whose destination is an indexed offset into a node.
42 /// Note: some functions that are marked as inline in DSNodeHandle are actually
43 /// defined in DSNode.h because they need knowledge of DSNode operation. Putting
44 /// them in a CPP file wouldn't help making them inlined and keeping DSNode and
45 /// DSNodeHandle (and friends) in one file complicates things.
49 mutable unsigned Offset;
50 void operator==(const DSNode *N); // DISALLOW, use to promote N to nodehandle
52 // Allow construction, destruction, and assignment...
53 DSNodeHandle(DSNode *n = 0, unsigned offs = 0) : N(0), Offset(offs) {
56 DSNodeHandle(const DSNodeHandle &H) : N(0), Offset(0) {
58 Offset = H.Offset; // Must read offset AFTER the getNode()
60 ~DSNodeHandle() { setNode((DSNode*)0); }
61 DSNodeHandle &operator=(const DSNodeHandle &H) {
62 if (&H == this) return *this; // Don't set offset to 0 if self assigning.
63 Offset = 0; setNode(H.getNode()); Offset = H.Offset;
67 bool operator<(const DSNodeHandle &H) const { // Allow sorting
68 return getNode() < H.getNode() || (N == H.N && Offset < H.Offset);
70 bool operator>(const DSNodeHandle &H) const { return H < *this; }
71 bool operator==(const DSNodeHandle &H) const { // Allow comparison
72 return getNode() == H.getNode() && Offset == H.Offset;
74 bool operator!=(const DSNodeHandle &H) const { return !operator==(H); }
76 inline void swap(DSNodeHandle &NH) {
77 std::swap(Offset, NH.Offset);
81 /// isNull - Check to see if getNode() == 0, without going through the trouble
82 /// of checking to see if we are forwarding...
83 bool isNull() const { return N == 0; }
85 // Allow explicit conversion to DSNode...
86 inline DSNode *getNode() const; // Defined inline in DSNode.h
87 unsigned getOffset() const { return Offset; }
89 inline void setNode(DSNode *N); // Defined inline in DSNode.h
90 void setOffset(unsigned O) {
91 //assert((!N || Offset < N->Size || (N->Size == 0 && Offset == 0) ||
92 // !N->ForwardNH.isNull()) && "Node handle offset out of range!");
93 //assert((!N || O < N->Size || (N->Size == 0 && O == 0) ||
94 // !N->ForwardNH.isNull()) && "Node handle offset out of range!");
98 void addEdgeTo(unsigned LinkNo, const DSNodeHandle &N);
99 void addEdgeTo(const DSNodeHandle &N) { addEdgeTo(0, N); }
101 /// mergeWith - Merge the logical node pointed to by 'this' with the node
102 /// pointed to by 'N'.
104 void mergeWith(const DSNodeHandle &N);
106 // hasLink - Return true if there is a link at the specified offset...
107 inline bool hasLink(unsigned Num) const;
109 /// getLink - Treat this current node pointer as a pointer to a structure of
110 /// some sort. This method will return the pointer a mem[this+Num]
112 inline const DSNodeHandle &getLink(unsigned Num) const;
113 inline DSNodeHandle &getLink(unsigned Num);
115 inline void setLink(unsigned Num, const DSNodeHandle &NH);
117 DSNode *HandleForwarding() const;
121 inline void swap(DSNodeHandle &NH1, DSNodeHandle &NH2) { NH1.swap(NH2); }
124 //===----------------------------------------------------------------------===//
125 /// DSCallSite - Representation of a call site via its call instruction,
126 /// the DSNode handle for the callee function (or function pointer), and
127 /// the DSNode handles for the function arguments.
130 CallInst *Inst; // Actual call site
131 Function *CalleeF; // The function called (direct call)
132 DSNodeHandle CalleeN; // The function node called (indirect call)
133 DSNodeHandle RetVal; // Returned value
134 std::vector<DSNodeHandle> CallArgs;// The pointer arguments
136 static void InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
137 const hash_map<const DSNode*, DSNode*> &NodeMap) {
138 if (DSNode *N = Src.getNode()) {
139 hash_map<const DSNode*, DSNode*>::const_iterator I = NodeMap.find(N);
140 assert(I != NodeMap.end() && "Not not in mapping!");
142 NH.setOffset(Src.getOffset());
143 NH.setNode(I->second);
147 static void InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
148 const hash_map<const DSNode*, DSNodeHandle> &NodeMap) {
149 if (DSNode *N = Src.getNode()) {
150 hash_map<const DSNode*, DSNodeHandle>::const_iterator I = NodeMap.find(N);
151 assert(I != NodeMap.end() && "Not not in mapping!");
153 NH.setOffset(Src.getOffset()+I->second.getOffset());
154 NH.setNode(I->second.getNode());
158 DSCallSite(); // DO NOT IMPLEMENT
160 /// Constructor. Note - This ctor destroys the argument vector passed in. On
161 /// exit, the argument vector is empty.
163 DSCallSite(CallInst &inst, const DSNodeHandle &rv, DSNode *Callee,
164 std::vector<DSNodeHandle> &Args)
165 : Inst(&inst), CalleeF(0), CalleeN(Callee), RetVal(rv) {
166 assert(Callee && "Null callee node specified for call site!");
169 DSCallSite(CallInst &inst, const DSNodeHandle &rv, Function *Callee,
170 std::vector<DSNodeHandle> &Args)
171 : Inst(&inst), CalleeF(Callee), RetVal(rv) {
172 assert(Callee && "Null callee function specified for call site!");
176 DSCallSite(const DSCallSite &DSCS) // Simple copy ctor
177 : Inst(DSCS.Inst), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
178 RetVal(DSCS.RetVal), CallArgs(DSCS.CallArgs) {}
180 /// Mapping copy constructor - This constructor takes a preexisting call site
181 /// to copy plus a map that specifies how the links should be transformed.
182 /// This is useful when moving a call site from one graph to another.
184 template<typename MapTy>
185 DSCallSite(const DSCallSite &FromCall, const MapTy &NodeMap) {
186 Inst = FromCall.Inst;
187 InitNH(RetVal, FromCall.RetVal, NodeMap);
188 InitNH(CalleeN, FromCall.CalleeN, NodeMap);
189 CalleeF = FromCall.CalleeF;
191 CallArgs.resize(FromCall.CallArgs.size());
192 for (unsigned i = 0, e = FromCall.CallArgs.size(); i != e; ++i)
193 InitNH(CallArgs[i], FromCall.CallArgs[i], NodeMap);
196 const DSCallSite &operator=(const DSCallSite &RHS) {
198 CalleeF = RHS.CalleeF;
199 CalleeN = RHS.CalleeN;
201 CallArgs = RHS.CallArgs;
205 /// isDirectCall - Return true if this call site is a direct call of the
206 /// function specified by getCalleeFunc. If not, it is an indirect call to
207 /// the node specified by getCalleeNode.
209 bool isDirectCall() const { return CalleeF != 0; }
210 bool isIndirectCall() const { return !isDirectCall(); }
213 // Accessor functions...
214 Function &getCaller() const;
215 CallInst &getCallInst() const { return *Inst; }
216 DSNodeHandle &getRetVal() { return RetVal; }
217 const DSNodeHandle &getRetVal() const { return RetVal; }
219 DSNode *getCalleeNode() const {
220 assert(!CalleeF && CalleeN.getNode()); return CalleeN.getNode();
222 Function *getCalleeFunc() const {
223 assert(!CalleeN.getNode() && CalleeF); return CalleeF;
226 unsigned getNumPtrArgs() const { return CallArgs.size(); }
228 DSNodeHandle &getPtrArg(unsigned i) {
229 assert(i < CallArgs.size() && "Argument to getPtrArgNode is out of range!");
232 const DSNodeHandle &getPtrArg(unsigned i) const {
233 assert(i < CallArgs.size() && "Argument to getPtrArgNode is out of range!");
237 void swap(DSCallSite &CS) {
239 std::swap(Inst, CS.Inst);
240 std::swap(RetVal, CS.RetVal);
241 std::swap(CalleeN, CS.CalleeN);
242 std::swap(CalleeF, CS.CalleeF);
243 std::swap(CallArgs, CS.CallArgs);
247 // MergeWith - Merge the return value and parameters of the these two call
249 void mergeWith(DSCallSite &CS) {
250 getRetVal().mergeWith(CS.getRetVal());
251 unsigned MinArgs = getNumPtrArgs();
252 if (CS.getNumPtrArgs() < MinArgs) MinArgs = CS.getNumPtrArgs();
254 for (unsigned a = 0; a != MinArgs; ++a)
255 getPtrArg(a).mergeWith(CS.getPtrArg(a));
258 /// markReachableNodes - This method recursively traverses the specified
259 /// DSNodes, marking any nodes which are reachable. All reachable nodes it
260 /// adds to the set, which allows it to only traverse visited nodes once.
262 void markReachableNodes(hash_set<DSNode*> &Nodes);
264 bool operator<(const DSCallSite &CS) const {
265 if (isDirectCall()) { // This must sort by callee first!
266 if (CS.isIndirectCall()) return true;
267 if (CalleeF < CS.CalleeF) return true;
268 if (CalleeF > CS.CalleeF) return false;
270 if (CS.isDirectCall()) return false;
271 if (CalleeN < CS.CalleeN) return true;
272 if (CalleeN > CS.CalleeN) return false;
274 if (RetVal < CS.RetVal) return true;
275 if (RetVal > CS.RetVal) return false;
276 return CallArgs < CS.CallArgs;
279 bool operator==(const DSCallSite &CS) const {
280 return RetVal == CS.RetVal && CalleeN == CS.CalleeN &&
281 CalleeF == CS.CalleeF && CallArgs == CS.CallArgs;
286 inline void swap(DSCallSite &CS1, DSCallSite &CS2) { CS1.swap(CS2); }