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/HashExtras.h"
15 #include "Support/hash_set"
23 class DSNode; // Each node in the graph
24 class DSGraph; // A graph for a function
26 namespace DS { // FIXME: After the paper, this should get cleaned up
27 enum { PointerShift = 3, // 64bit ptrs = 3, 32 bit ptrs = 2
28 PointerSize = 1 << PointerShift
31 // isPointerType - Return true if this first class type is big enough to hold
34 bool isPointerType(const Type *Ty);
37 //===----------------------------------------------------------------------===//
38 /// DSNodeHandle - Implement a "handle" to a data structure node that takes care
39 /// of all of the add/un'refing of the node to prevent the backpointers in the
40 /// graph from getting out of date. This class represents a "pointer" in the
41 /// graph, whose destination is an indexed offset into a node.
43 /// Note: some functions that are marked as inline in DSNodeHandle are actually
44 /// defined in DSNode.h because they need knowledge of DSNode operation. Putting
45 /// them in a CPP file wouldn't help making them inlined and keeping DSNode and
46 /// DSNodeHandle (and friends) in one file complicates things.
50 mutable unsigned Offset;
51 void operator==(const DSNode *N); // DISALLOW, use to promote N to nodehandle
53 // Allow construction, destruction, and assignment...
54 DSNodeHandle(DSNode *n = 0, unsigned offs = 0) : N(0), Offset(offs) {
57 DSNodeHandle(const DSNodeHandle &H) : N(0), Offset(0) {
59 Offset = H.Offset; // Must read offset AFTER the getNode()
61 ~DSNodeHandle() { setNode((DSNode*)0); }
62 DSNodeHandle &operator=(const DSNodeHandle &H) {
63 if (&H == this) return *this; // Don't set offset to 0 if self assigning.
64 Offset = 0; setNode(H.getNode()); Offset = H.Offset;
68 bool operator<(const DSNodeHandle &H) const { // Allow sorting
69 return getNode() < H.getNode() || (N == H.N && Offset < H.Offset);
71 bool operator>(const DSNodeHandle &H) const { return H < *this; }
72 bool operator==(const DSNodeHandle &H) const { // Allow comparison
73 return getNode() == H.getNode() && Offset == H.Offset;
75 bool operator!=(const DSNodeHandle &H) const { return !operator==(H); }
77 inline void swap(DSNodeHandle &NH) {
78 std::swap(Offset, NH.Offset);
82 /// isNull - Check to see if getNode() == 0, without going through the trouble
83 /// of checking to see if we are forwarding...
84 bool isNull() const { return N == 0; }
86 // Allow explicit conversion to DSNode...
87 inline DSNode *getNode() const; // Defined inline in DSNode.h
88 unsigned getOffset() const { return Offset; }
90 inline void setNode(DSNode *N); // Defined inline in DSNode.h
91 void setOffset(unsigned O) {
92 //assert((!N || Offset < N->Size || (N->Size == 0 && Offset == 0) ||
93 // !N->ForwardNH.isNull()) && "Node handle offset out of range!");
94 //assert((!N || O < N->Size || (N->Size == 0 && O == 0) ||
95 // !N->ForwardNH.isNull()) && "Node handle offset out of range!");
99 void addEdgeTo(unsigned LinkNo, const DSNodeHandle &N);
100 void addEdgeTo(const DSNodeHandle &N) { addEdgeTo(0, N); }
102 /// mergeWith - Merge the logical node pointed to by 'this' with the node
103 /// pointed to by 'N'.
105 void mergeWith(const DSNodeHandle &N);
107 // hasLink - Return true if there is a link at the specified offset...
108 inline bool hasLink(unsigned Num) const;
110 /// getLink - Treat this current node pointer as a pointer to a structure of
111 /// some sort. This method will return the pointer a mem[this+Num]
113 inline const DSNodeHandle &getLink(unsigned Num) const;
114 inline DSNodeHandle &getLink(unsigned Num);
116 inline void setLink(unsigned Num, const DSNodeHandle &NH);
118 DSNode *HandleForwarding() const;
122 inline void swap(DSNodeHandle &NH1, DSNodeHandle &NH2) { NH1.swap(NH2); }
125 //===----------------------------------------------------------------------===//
126 /// DSCallSite - Representation of a call site via its call instruction,
127 /// the DSNode handle for the callee function (or function pointer), and
128 /// the DSNode handles for the function arguments.
131 CallInst *Inst; // Actual call site
132 Function *CalleeF; // The function called (direct call)
133 DSNodeHandle CalleeN; // The function node called (indirect call)
134 DSNodeHandle RetVal; // Returned value
135 std::vector<DSNodeHandle> CallArgs;// The pointer arguments
137 static void InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
138 const hash_map<const DSNode*, DSNode*> &NodeMap) {
139 if (DSNode *N = Src.getNode()) {
140 hash_map<const DSNode*, DSNode*>::const_iterator I = NodeMap.find(N);
141 assert(I != NodeMap.end() && "Not not in mapping!");
143 NH.setOffset(Src.getOffset());
144 NH.setNode(I->second);
148 static void InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
149 const hash_map<const DSNode*, DSNodeHandle> &NodeMap) {
150 if (DSNode *N = Src.getNode()) {
151 hash_map<const DSNode*, DSNodeHandle>::const_iterator I = NodeMap.find(N);
152 assert(I != NodeMap.end() && "Not not in mapping!");
154 NH.setOffset(Src.getOffset()+I->second.getOffset());
155 NH.setNode(I->second.getNode());
159 DSCallSite(); // DO NOT IMPLEMENT
161 /// Constructor. Note - This ctor destroys the argument vector passed in. On
162 /// exit, the argument vector is empty.
164 DSCallSite(CallInst &inst, const DSNodeHandle &rv, DSNode *Callee,
165 std::vector<DSNodeHandle> &Args)
166 : Inst(&inst), CalleeF(0), CalleeN(Callee), RetVal(rv) {
167 assert(Callee && "Null callee node specified for call site!");
170 DSCallSite(CallInst &inst, const DSNodeHandle &rv, Function *Callee,
171 std::vector<DSNodeHandle> &Args)
172 : Inst(&inst), CalleeF(Callee), RetVal(rv) {
173 assert(Callee && "Null callee function specified for call site!");
177 DSCallSite(const DSCallSite &DSCS) // Simple copy ctor
178 : Inst(DSCS.Inst), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
179 RetVal(DSCS.RetVal), CallArgs(DSCS.CallArgs) {}
181 /// Mapping copy constructor - This constructor takes a preexisting call site
182 /// to copy plus a map that specifies how the links should be transformed.
183 /// This is useful when moving a call site from one graph to another.
185 template<typename MapTy>
186 DSCallSite(const DSCallSite &FromCall, const MapTy &NodeMap) {
187 Inst = FromCall.Inst;
188 InitNH(RetVal, FromCall.RetVal, NodeMap);
189 InitNH(CalleeN, FromCall.CalleeN, NodeMap);
190 CalleeF = FromCall.CalleeF;
192 CallArgs.resize(FromCall.CallArgs.size());
193 for (unsigned i = 0, e = FromCall.CallArgs.size(); i != e; ++i)
194 InitNH(CallArgs[i], FromCall.CallArgs[i], NodeMap);
197 /// isDirectCall - Return true if this call site is a direct call of the
198 /// function specified by getCalleeFunc. If not, it is an indirect call to
199 /// the node specified by getCalleeNode.
201 bool isDirectCall() const { return CalleeF != 0; }
202 bool isIndirectCall() const { return !isDirectCall(); }
205 // Accessor functions...
206 Function &getCaller() const;
207 CallInst &getCallInst() const { return *Inst; }
208 DSNodeHandle &getRetVal() { return RetVal; }
209 const DSNodeHandle &getRetVal() const { return RetVal; }
211 DSNode *getCalleeNode() const {
212 assert(!CalleeF && CalleeN.getNode()); return CalleeN.getNode();
214 Function *getCalleeFunc() const {
215 assert(!CalleeN.getNode() && CalleeF); return CalleeF;
218 unsigned getNumPtrArgs() const { return CallArgs.size(); }
220 DSNodeHandle &getPtrArg(unsigned i) {
221 assert(i < CallArgs.size() && "Argument to getPtrArgNode is out of range!");
224 const DSNodeHandle &getPtrArg(unsigned i) const {
225 assert(i < CallArgs.size() && "Argument to getPtrArgNode is out of range!");
229 void swap(DSCallSite &CS) {
231 std::swap(Inst, CS.Inst);
232 std::swap(RetVal, CS.RetVal);
233 std::swap(CalleeN, CS.CalleeN);
234 std::swap(CalleeF, CS.CalleeF);
235 std::swap(CallArgs, CS.CallArgs);
239 // MergeWith - Merge the return value and parameters of the these two call
241 void mergeWith(DSCallSite &CS) {
242 getRetVal().mergeWith(CS.getRetVal());
243 unsigned MinArgs = getNumPtrArgs();
244 if (CS.getNumPtrArgs() < MinArgs) MinArgs = CS.getNumPtrArgs();
246 for (unsigned a = 0; a != MinArgs; ++a)
247 getPtrArg(a).mergeWith(CS.getPtrArg(a));
250 /// markReachableNodes - This method recursively traverses the specified
251 /// DSNodes, marking any nodes which are reachable. All reachable nodes it
252 /// adds to the set, which allows it to only traverse visited nodes once.
254 void markReachableNodes(hash_set<DSNode*> &Nodes);
256 bool operator<(const DSCallSite &CS) const {
257 if (isDirectCall()) { // This must sort by callee first!
258 if (CS.isIndirectCall()) return true;
259 if (CalleeF < CS.CalleeF) return true;
260 if (CalleeF > CS.CalleeF) return false;
262 if (CS.isDirectCall()) return false;
263 if (CalleeN < CS.CalleeN) return true;
264 if (CalleeN > CS.CalleeN) return false;
266 if (RetVal < CS.RetVal) return true;
267 if (RetVal > CS.RetVal) return false;
268 return CallArgs < CS.CallArgs;
271 bool operator==(const DSCallSite &CS) const {
272 return RetVal == CS.RetVal && CalleeN == CS.CalleeN &&
273 CalleeF == CS.CalleeF && CallArgs == CS.CallArgs;
278 inline void swap(DSCallSite &CS1, DSCallSite &CS2) { CS1.swap(CS2); }