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
13 #include "Support/HashExtras.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39 /// graph from getting out of date.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 Offset = 0; setNode(H.getNode()); Offset = H.Offset;
66 bool operator<(const DSNodeHandle &H) const { // Allow sorting
67 return getNode() < H.getNode() || (N == H.N && Offset < H.Offset);
69 bool operator>(const DSNodeHandle &H) const { return H < *this; }
70 bool operator==(const DSNodeHandle &H) const { // Allow comparison
71 return getNode() == H.getNode() && Offset == H.Offset;
73 bool operator!=(const DSNodeHandle &H) const { return !operator==(H); }
75 inline void swap(DSNodeHandle &NH) {
76 std::swap(Offset, NH.Offset);
80 /// isNull - Check to see if getNode() == 0, without going through the trouble
81 /// of checking to see if we are forwarding...
82 bool isNull() const { return N == 0; }
84 // Allow explicit conversion to DSNode...
85 inline DSNode *getNode() const; // Defined inline in DSNode.h
86 unsigned getOffset() const { return Offset; }
88 inline void setNode(DSNode *N); // Defined inline in DSNode.h
89 void setOffset(unsigned O) {
90 //assert((!N || Offset < N->Size || (N->Size == 0 && Offset == 0) ||
91 // !N->ForwardNH.isNull()) && "Node handle offset out of range!");
92 //assert((!N || O < N->Size || (N->Size == 0 && O == 0) ||
93 // !N->ForwardNH.isNull()) && "Node handle offset out of range!");
97 void addEdgeTo(unsigned LinkNo, const DSNodeHandle &N);
98 void addEdgeTo(const DSNodeHandle &N) { addEdgeTo(0, N); }
100 /// mergeWith - Merge the logical node pointed to by 'this' with the node
101 /// pointed to by 'N'.
103 void mergeWith(const DSNodeHandle &N);
105 // hasLink - Return true if there is a link at the specified offset...
106 inline bool hasLink(unsigned Num) const;
108 /// getLink - Treat this current node pointer as a pointer to a structure of
109 /// some sort. This method will return the pointer a mem[this+Num]
111 inline const DSNodeHandle &getLink(unsigned Num) const;
112 inline DSNodeHandle &getLink(unsigned Num);
114 inline void setLink(unsigned Num, const DSNodeHandle &NH);
118 inline void swap(DSNodeHandle &NH1, DSNodeHandle &NH2) { NH1.swap(NH2); }
121 //===----------------------------------------------------------------------===//
122 /// DSCallSite - Representation of a call site via its call instruction,
123 /// the DSNode handle for the callee function (or function pointer), and
124 /// the DSNode handles for the function arguments.
127 CallInst *Inst; // Actual call site
128 Function *CalleeF; // The function called (direct call)
129 DSNodeHandle CalleeN; // The function node called (indirect call)
130 DSNodeHandle RetVal; // Returned value
131 std::vector<DSNodeHandle> CallArgs;// The pointer arguments
133 static void InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
134 const hash_map<const DSNode*, DSNode*> &NodeMap) {
135 if (DSNode *N = Src.getNode()) {
136 hash_map<const DSNode*, DSNode*>::const_iterator I = NodeMap.find(N);
137 assert(I != NodeMap.end() && "Not not in mapping!");
139 NH.setOffset(Src.getOffset());
140 NH.setNode(I->second);
144 static void InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
145 const hash_map<const DSNode*, DSNodeHandle> &NodeMap) {
146 if (DSNode *N = Src.getNode()) {
147 hash_map<const DSNode*, DSNodeHandle>::const_iterator I = NodeMap.find(N);
148 assert(I != NodeMap.end() && "Not not in mapping!");
150 NH.setOffset(Src.getOffset()+I->second.getOffset());
151 NH.setNode(I->second.getNode());
155 DSCallSite(); // DO NOT IMPLEMENT
157 /// Constructor. Note - This ctor destroys the argument vector passed in. On
158 /// exit, the argument vector is empty.
160 DSCallSite(CallInst &inst, const DSNodeHandle &rv, DSNode *Callee,
161 std::vector<DSNodeHandle> &Args)
162 : Inst(&inst), CalleeF(0), CalleeN(Callee), RetVal(rv) {
163 assert(Callee && "Null callee node specified for call site!");
166 DSCallSite(CallInst &inst, const DSNodeHandle &rv, Function *Callee,
167 std::vector<DSNodeHandle> &Args)
168 : Inst(&inst), CalleeF(Callee), RetVal(rv) {
169 assert(Callee && "Null callee function specified for call site!");
173 DSCallSite(const DSCallSite &DSCS) // Simple copy ctor
174 : Inst(DSCS.Inst), CalleeF(DSCS.CalleeF), CalleeN(DSCS.CalleeN),
175 RetVal(DSCS.RetVal), CallArgs(DSCS.CallArgs) {}
177 /// Mapping copy constructor - This constructor takes a preexisting call site
178 /// to copy plus a map that specifies how the links should be transformed.
179 /// This is useful when moving a call site from one graph to another.
181 template<typename MapTy>
182 DSCallSite(const DSCallSite &FromCall, const MapTy &NodeMap) {
183 Inst = FromCall.Inst;
184 InitNH(RetVal, FromCall.RetVal, NodeMap);
185 InitNH(CalleeN, FromCall.CalleeN, NodeMap);
186 CalleeF = FromCall.CalleeF;
188 CallArgs.resize(FromCall.CallArgs.size());
189 for (unsigned i = 0, e = FromCall.CallArgs.size(); i != e; ++i)
190 InitNH(CallArgs[i], FromCall.CallArgs[i], NodeMap);
193 /// isDirectCall - Return true if this call site is a direct call of the
194 /// function specified by getCalleeFunc. If not, it is an indirect call to
195 /// the node specified by getCalleeNode.
197 bool isDirectCall() const { return CalleeF != 0; }
198 bool isIndirectCall() const { return !isDirectCall(); }
201 // Accessor functions...
202 Function &getCaller() const;
203 CallInst &getCallInst() const { return *Inst; }
204 DSNodeHandle &getRetVal() { return RetVal; }
205 const DSNodeHandle &getRetVal() const { return RetVal; }
207 DSNode *getCalleeNode() const {
208 assert(!CalleeF && CalleeN.getNode()); return CalleeN.getNode();
210 Function *getCalleeFunc() const {
211 assert(!CalleeN.getNode() && CalleeF); return CalleeF;
214 unsigned getNumPtrArgs() const { return CallArgs.size(); }
216 DSNodeHandle &getPtrArg(unsigned i) {
217 assert(i < CallArgs.size() && "Argument to getPtrArgNode is out of range!");
220 const DSNodeHandle &getPtrArg(unsigned i) const {
221 assert(i < CallArgs.size() && "Argument to getPtrArgNode is out of range!");
225 void swap(DSCallSite &CS) {
227 std::swap(Inst, CS.Inst);
228 std::swap(RetVal, CS.RetVal);
229 std::swap(CalleeN, CS.CalleeN);
230 std::swap(CalleeF, CS.CalleeF);
231 std::swap(CallArgs, CS.CallArgs);
235 // MergeWith - Merge the return value and parameters of the these two call
237 void mergeWith(DSCallSite &CS) {
238 getRetVal().mergeWith(CS.getRetVal());
239 unsigned MinArgs = getNumPtrArgs();
240 if (CS.getNumPtrArgs() < MinArgs) MinArgs = CS.getNumPtrArgs();
242 for (unsigned a = 0; a != MinArgs; ++a)
243 getPtrArg(a).mergeWith(CS.getPtrArg(a));
246 /// markReachableNodes - This method recursively traverses the specified
247 /// DSNodes, marking any nodes which are reachable. All reachable nodes it
248 /// adds to the set, which allows it to only traverse visited nodes once.
250 void markReachableNodes(hash_set<DSNode*> &Nodes);
252 bool operator<(const DSCallSite &CS) const {
253 if (isDirectCall()) { // This must sort by callee first!
254 if (CS.isIndirectCall()) return true;
255 if (CalleeF < CS.CalleeF) return true;
256 if (CalleeF > CS.CalleeF) return false;
258 if (CS.isDirectCall()) return false;
259 if (CalleeN < CS.CalleeN) return true;
260 if (CalleeN > CS.CalleeN) return false;
262 if (RetVal < CS.RetVal) return true;
263 if (RetVal > CS.RetVal) return false;
264 return CallArgs < CS.CallArgs;
267 bool operator==(const DSCallSite &CS) const {
268 return RetVal == CS.RetVal && CalleeN == CS.CalleeN &&
269 CalleeF == CS.CalleeF && CallArgs == CS.CallArgs;
274 inline void swap(DSCallSite &CS1, DSCallSite &CS2) { CS1.swap(CS2); }