diff --git a/include/llvm/Analysis/DSGraph.h b/include/llvm/Analysis/DSGraph.h new file mode 100644 index 00000000000..af2105576e0 --- /dev/null +++ b/include/llvm/Analysis/DSGraph.h @@ -0,0 +1,477 @@ +//===- DSGraph.h - Represent a collection of data structures ----*- C++ -*-===// +// +// This header defines the primative classes that make up a data structure +// graph. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_ANALYSIS_DSGRAPH_H +#define LLVM_ANALYSIS_DSGRAPH_H + +#include "llvm/Pass.h" + +class GlobalValue; +class Type; + +class DSNode; // Each node in the graph +class DSGraph; // A graph for a function +class DSNodeIterator; // Data structure graph traversal iterator + +//===----------------------------------------------------------------------===// +/// DSNodeHandle - Implement a "handle" to a data structure node that takes care +/// of all of the add/un'refing of the node to prevent the backpointers in the +/// graph from getting out of date. This class represents a "pointer" in the +/// graph, whose destination is an indexed offset into a node. +/// +class DSNodeHandle { + DSNode *N; + unsigned Offset; +public: + // Allow construction, destruction, and assignment... + DSNodeHandle(DSNode *n = 0, unsigned offs = 0) : N(0), Offset(offs) { + setNode(n); + } + DSNodeHandle(const DSNodeHandle &H) : N(0), Offset(H.Offset) { setNode(H.N); } + ~DSNodeHandle() { setNode((DSNode*)0); } + DSNodeHandle &operator=(const DSNodeHandle &H) { + setNode(H.N); Offset = H.Offset; + return *this; + } + + bool operator<(const DSNodeHandle &H) const { // Allow sorting + return N < H.N || (N == H.N && Offset < H.Offset); + } + bool operator==(const DSNodeHandle &H) const { // Allow comparison + return N == H.N && Offset == H.Offset; + } + bool operator!=(const DSNodeHandle &H) const { return !operator==(H); } + + // Allow explicit conversion to DSNode... + DSNode *getNode() const { return N; } + unsigned getOffset() const { return Offset; } + + inline void setNode(DSNode *N); // Defined inline later... + void setOffset(unsigned O) { Offset = O; } + + void addEdgeTo(unsigned LinkNo, const DSNodeHandle &N); + void addEdgeTo(const DSNodeHandle &N) { addEdgeTo(0, N); } + + /// mergeWith - Merge the logical node pointed to by 'this' with the node + /// pointed to by 'N'. + /// + void mergeWith(const DSNodeHandle &N); + + // hasLink - Return true if there is a link at the specified offset... + inline bool hasLink(unsigned Num) const; + + /// getLink - Treat this current node pointer as a pointer to a structure of + /// some sort. This method will return the pointer a mem[this+Num] + /// + inline const DSNodeHandle *getLink(unsigned Num) const; + inline DSNodeHandle *getLink(unsigned Num); + + inline void setLink(unsigned Num, const DSNodeHandle &NH); +}; + + +//===----------------------------------------------------------------------===// +/// DSNode - Data structure node class +/// +/// This class represents an untyped memory object of Size bytes. It keeps +/// track of any pointers that have been stored into the object as well as the +/// different types represented in this object. +/// +class DSNode { + /// Links - Contains one entry for every _distinct_ pointer field in the + /// memory block. These are demand allocated and indexed by the MergeMap + /// vector. + /// + std::vector Links; + + /// MergeMap - Maps from every byte in the object to a signed byte number. + /// This map is neccesary due to the merging that is possible as part of the + /// unification algorithm. To merge two distinct bytes of the object together + /// into a single logical byte, the indexes for the two bytes are set to the + /// same value. This fully general merging is capable of representing all + /// manners of array merging if neccesary. + /// + /// This map is also used to map outgoing pointers to various byte offsets in + /// this data structure node. If this value is >= 0, then it indicates that + /// the numbered entry in the Links vector contains the outgoing edge for this + /// byte offset. In this way, the Links vector can be demand allocated and + /// byte elements of the node may be merged without needing a Link allocated + /// for it. + /// + /// Initially, each each element of the MergeMap is assigned a unique negative + /// number, which are then merged as the unification occurs. + /// + std::vector MergeMap; + + /// Referrers - Keep track of all of the node handles that point to this + /// DSNode. These pointers may need to be updated to point to a different + /// node if this node gets merged with it. + /// + std::vector Referrers; + + /// TypeEntries - As part of the merging process of this algorithm, nodes of + /// different types can be represented by this single DSNode. This vector is + /// kept sorted. + /// + typedef std::pair TypeRec; + std::vector TypeEntries; + + /// Globals - The list of global values that are merged into this node. + /// + std::vector Globals; + + void operator=(const DSNode &); // DO NOT IMPLEMENT +public: + enum NodeTy { + ShadowNode = 0, // Nothing is known about this node... + ScalarNode = 1 << 0, // Scalar of the current function contains this value + AllocaNode = 1 << 1, // This node was allocated with alloca + NewNode = 1 << 2, // This node was allocated with malloc + GlobalNode = 1 << 3, // This node was allocated by a global var decl + Incomplete = 1 << 4, // This node may not be complete + }; + + /// NodeType - A union of the above bits. "Shadow" nodes do not add any flags + /// to the nodes in the data structure graph, so it is possible to have nodes + /// with a value of 0 for their NodeType. Scalar and Alloca markers go away + /// when function graphs are inlined. + /// + unsigned char NodeType; + + DSNode(enum NodeTy NT, const Type *T); + DSNode(const DSNode &); + + ~DSNode() { +#ifndef NDEBUG + dropAllReferences(); // Only needed to satisfy assertion checks... + assert(Referrers.empty() && "Referrers to dead node exist!"); +#endif + } + + // Iterator for graph interface... + typedef DSNodeIterator iterator; + inline iterator begin(); // Defined in DataStructureGraph.h + inline iterator end(); + + //===-------------------------------------------------- + // Accessors + + // getSize - Return the maximum number of bytes occupied by this object... + unsigned getSize() const { return MergeMap.size(); } + + // getTypeEntries - Return the possible types and their offsets in this object + const std::vector &getTypeEntries() const { return TypeEntries; } + + // getReferrers - Return a list of the pointers to this node... + const std::vector &getReferrers() const { return Referrers; } + + + /// hasLink - Return true if this memory object has a link at the specified + /// location. + /// + bool hasLink(unsigned i) const { + assert(i < getSize() && "Field Link index is out of range!"); + return MergeMap[i] >= 0; + } + + DSNodeHandle *getLink(unsigned i) { + if (hasLink(i)) + return &Links[MergeMap[i]]; + return 0; + } + const DSNodeHandle *getLink(unsigned i) const { + if (hasLink(i)) + return &Links[MergeMap[i]]; + return 0; + } + + /// setLink - Set the link at the specified offset to the specified + /// NodeHandle, replacing what was there. It is uncommon to use this method, + /// instead one of the higher level methods should be used, below. + /// + void setLink(unsigned i, const DSNodeHandle &NH); + + /// addEdgeTo - Add an edge from the current node to the specified node. This + /// can cause merging of nodes in the graph. + /// + void addEdgeTo(unsigned Offset, const DSNodeHandle &NH); + + /// mergeWith - Merge this node and the specified node, moving all links to + /// and from the argument node into the current node, deleting the node + /// argument. Offset indicates what offset the specified node is to be merged + /// into the current node. + /// + /// The specified node may be a null pointer (in which case, nothing happens). + /// + void mergeWith(const DSNodeHandle &NH, unsigned Offset); + + /// addGlobal - Add an entry for a global value to the Globals list. This + /// also marks the node with the 'G' flag if it does not already have it. + /// + void addGlobal(GlobalValue *GV); + const std::vector &getGlobals() const { return Globals; } + std::vector &getGlobals() { return Globals; } + + void print(std::ostream &O, const DSGraph *G) const; + void dump() const; + + void dropAllReferences() { + Links.clear(); + } + + /// remapLinks - Change all of the Links in the current node according to the + /// specified mapping. + void remapLinks(std::map &OldNodeMap); + +private: + friend class DSNodeHandle; + // addReferrer - Keep the referrer set up to date... + void addReferrer(DSNodeHandle *H) { Referrers.push_back(H); } + void removeReferrer(DSNodeHandle *H); + + /// rewriteMergeMap - Loop over the mergemap, replacing any references to the + /// index From to be references to the index To. + /// + void rewriteMergeMap(signed char From, signed char To) { + assert(From != To && "Cannot change something into itself!"); + for (unsigned i = 0, e = MergeMap.size(); i != e; ++i) + if (MergeMap[i] == From) + MergeMap[i] = To; + } + + /// mergeMappedValues - This is the higher level form of rewriteMergeMap. It + /// is fully capable of merging links together if neccesary as well as simply + /// rewriting the map entries. + /// + void mergeMappedValues(signed char V1, signed char V2); +}; + + +//===----------------------------------------------------------------------===// +// Define inline DSNodeHandle functions that depend on the definition of DSNode +// + +inline void DSNodeHandle::setNode(DSNode *n) { + if (N) N->removeReferrer(this); + N = n; + if (N) N->addReferrer(this); +} + +inline bool DSNodeHandle::hasLink(unsigned Num) const { + assert(N && "DSNodeHandle does not point to a node yet!"); + return N->hasLink(Num+Offset); +} + + +/// getLink - Treat this current node pointer as a pointer to a structure of +/// some sort. This method will return the pointer a mem[this+Num] +/// +inline const DSNodeHandle *DSNodeHandle::getLink(unsigned Num) const { + assert(N && "DSNodeHandle does not point to a node yet!"); + return N->getLink(Num+Offset); +} +inline DSNodeHandle *DSNodeHandle::getLink(unsigned Num) { + assert(N && "DSNodeHandle does not point to a node yet!"); + return N->getLink(Num+Offset); +} + +inline void DSNodeHandle::setLink(unsigned Num, const DSNodeHandle &NH) { + assert(N && "DSNodeHandle does not point to a node yet!"); + N->setLink(Num+Offset, NH); +} + +/// addEdgeTo - Add an edge from the current node to the specified node. This +/// can cause merging of nodes in the graph. +/// +inline void DSNodeHandle::addEdgeTo(unsigned LinkNo, const DSNodeHandle &Node) { + assert(N && "DSNodeHandle does not point to a node yet!"); + N->addEdgeTo(LinkNo+Offset, Node); +} + +/// mergeWith - Merge the logical node pointed to by 'this' with the node +/// pointed to by 'N'. +/// +inline void DSNodeHandle::mergeWith(const DSNodeHandle &Node) { + assert(N && "DSNodeHandle does not point to a node yet!"); + N->mergeWith(Node, Offset); +} + + +//===----------------------------------------------------------------------===// +/// DSGraph - The graph that represents a function. +/// +class DSGraph { + Function *Func; + std::vector Nodes; + DSNodeHandle RetNode; // Node that gets returned... + std::map ValueMap; + +#if 0 + // GlobalsGraph -- Reference to the common graph of globally visible objects. + // This includes GlobalValues, New nodes, Cast nodes, and Calls. + // + GlobalDSGraph* GlobalsGraph; +#endif + + // FunctionCalls - This vector maintains a single entry for each call + // instruction in the current graph. Each call entry contains DSNodeHandles + // that refer to the arguments that are passed into the function call. The + // first entry in the vector is the scalar that holds the return value for the + // call, the second is the function scalar being invoked, and the rest are + // pointer arguments to the function. + // + std::vector > FunctionCalls; + +#if 0 + // OrigFunctionCalls - This vector retains a copy of the original function + // calls of the current graph. This is needed to support top-down inlining + // after bottom-up inlining is complete, since the latter deletes call nodes. + // + std::vector > OrigFunctionCalls; + + // PendingCallers - This vector records all unresolved callers of the + // current function, i.e., ones whose graphs have not been inlined into + // the current graph. As long as there are unresolved callers, the nodes + // for formal arguments in the current graph cannot be eliminated, and + // nodes in the graph reachable from the formal argument nodes or + // global variable nodes must be considered incomplete. + std::set PendingCallers; +#endif + +protected: + +#if 0 + // clone all the call nodes and save the copies in OrigFunctionCalls + void saveOrigFunctionCalls() { + assert(OrigFunctionCalls.size() == 0 && "Do this only once!"); + OrigFunctionCalls = FunctionCalls; + } + + // get the saved copies of the original function call nodes + std::vector > &getOrigFunctionCalls() { + return OrigFunctionCalls; + } +#endif + + void operator=(const DSGraph &); // DO NOT IMPLEMENT +public: + DSGraph() : Func(0) {} // Create a new, empty, DSGraph. + DSGraph(Function &F); // Compute the local DSGraph + DSGraph(const DSGraph &DSG); // Copy ctor + ~DSGraph(); + + bool hasFunction() const { return Func != 0; } + Function &getFunction() const { return *Func; } + + /// getNodes - Get a vector of all the nodes in the graph + /// + const std::vector &getNodes() const { return Nodes; } + std::vector &getNodes() { return Nodes; } + + /// addNode - Add a new node to the graph. + /// + void addNode(DSNode *N) { Nodes.push_back(N); } + + /// getValueMap - Get a map that describes what the nodes the scalars in this + /// function point to... + /// + std::map &getValueMap() { return ValueMap; } + const std::map &getValueMap() const { return ValueMap;} + + std::vector > &getFunctionCalls() { + return FunctionCalls; + } + const std::vector > &getFunctionCalls() const { + return FunctionCalls; + } + + const DSNodeHandle &getRetNode() const { return RetNode; } + DSNodeHandle &getRetNode() { return RetNode; } + + unsigned getGraphSize() const { + return Nodes.size(); + } + + void print(std::ostream &O) const; + void dump() const; + void writeGraphToFile(std::ostream &O, const std::string &GraphName); + + // maskNodeTypes - Apply a mask to all of the node types in the graph. This + // is useful for clearing out markers like Scalar or Incomplete. + // + void maskNodeTypes(unsigned char Mask); + void maskIncompleteMarkers() { maskNodeTypes(~DSNode::Incomplete); } + + // markIncompleteNodes - Traverse the graph, identifying nodes that may be + // modified by other functions that have not been resolved yet. This marks + // nodes that are reachable through three sources of "unknownness": + // Global Variables, Function Calls, and Incoming Arguments + // + // For any node that may have unknown components (because something outside + // the scope of current analysis may have modified it), the 'Incomplete' flag + // is added to the NodeType. + // + void markIncompleteNodes(bool markFormalArgs = true); + + // removeTriviallyDeadNodes - After the graph has been constructed, this + // method removes all unreachable nodes that are created because they got + // merged with other nodes in the graph. + // + void removeTriviallyDeadNodes(bool KeepAllGlobals = false); + + // removeDeadNodes - Use a more powerful reachability analysis to eliminate + // subgraphs that are unreachable. This often occurs because the data + // structure doesn't "escape" into it's caller, and thus should be eliminated + // from the caller's graph entirely. This is only appropriate to use when + // inlining graphs. + // + void removeDeadNodes(bool KeepAllGlobals = false, bool KeepCalls = true); + +#if 0 + // AddCaller - add a known caller node into the graph and mark it pending. + // getCallers - get a vector of the functions that call this one + // getCallersPending - get a matching vector of bools indicating if each + // caller's DSGraph has been resolved into this one. + // + void addCaller(Function &caller) { + PendingCallers.insert(&caller); + } + std::set &getPendingCallers() { + return PendingCallers; + } +#endif + + // cloneInto - Clone the specified DSGraph into the current graph, returning + // the Return node of the graph. The translated ValueMap for the old function + // is filled into the OldValMap member. + // If StripScalars (StripAllocas) is set to true, Scalar (Alloca) markers + // are removed from the graph as the graph is being cloned. + // If CopyCallers is set to true, the PendingCallers list is copied. + // If CopyOrigCalls is set to true, the OrigFunctionCalls list is copied. + // + DSNodeHandle cloneInto(const DSGraph &G, + std::map &OldValMap, + std::map &OldNodeMap, + bool StripScalars = false, bool StripAllocas = false, + bool CopyCallers = true, bool CopyOrigCalls = true); + +#if 0 + // cloneGlobalInto - Clone the given global node (or the node for the given + // GlobalValue) from the GlobalsGraph and all its target links (recursively). + // + DSNode* cloneGlobalInto(const DSNode* GNode); + DSNode* cloneGlobalInto(GlobalValue* GV) { + assert(!GV || (((DSGraph*) GlobalsGraph)->ValueMap[GV] != 0)); + return GV? cloneGlobalInto(((DSGraph*) GlobalsGraph)->ValueMap[GV]) : 0; + } +#endif + +private: + bool isNodeDead(DSNode *N); +}; + +#endif diff --git a/include/llvm/Analysis/DataStructure/DSGraph.h b/include/llvm/Analysis/DataStructure/DSGraph.h new file mode 100644 index 00000000000..af2105576e0 --- /dev/null +++ b/include/llvm/Analysis/DataStructure/DSGraph.h @@ -0,0 +1,477 @@ +//===- DSGraph.h - Represent a collection of data structures ----*- C++ -*-===// +// +// This header defines the primative classes that make up a data structure +// graph. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_ANALYSIS_DSGRAPH_H +#define LLVM_ANALYSIS_DSGRAPH_H + +#include "llvm/Pass.h" + +class GlobalValue; +class Type; + +class DSNode; // Each node in the graph +class DSGraph; // A graph for a function +class DSNodeIterator; // Data structure graph traversal iterator + +//===----------------------------------------------------------------------===// +/// DSNodeHandle - Implement a "handle" to a data structure node that takes care +/// of all of the add/un'refing of the node to prevent the backpointers in the +/// graph from getting out of date. This class represents a "pointer" in the +/// graph, whose destination is an indexed offset into a node. +/// +class DSNodeHandle { + DSNode *N; + unsigned Offset; +public: + // Allow construction, destruction, and assignment... + DSNodeHandle(DSNode *n = 0, unsigned offs = 0) : N(0), Offset(offs) { + setNode(n); + } + DSNodeHandle(const DSNodeHandle &H) : N(0), Offset(H.Offset) { setNode(H.N); } + ~DSNodeHandle() { setNode((DSNode*)0); } + DSNodeHandle &operator=(const DSNodeHandle &H) { + setNode(H.N); Offset = H.Offset; + return *this; + } + + bool operator<(const DSNodeHandle &H) const { // Allow sorting + return N < H.N || (N == H.N && Offset < H.Offset); + } + bool operator==(const DSNodeHandle &H) const { // Allow comparison + return N == H.N && Offset == H.Offset; + } + bool operator!=(const DSNodeHandle &H) const { return !operator==(H); } + + // Allow explicit conversion to DSNode... + DSNode *getNode() const { return N; } + unsigned getOffset() const { return Offset; } + + inline void setNode(DSNode *N); // Defined inline later... + void setOffset(unsigned O) { Offset = O; } + + void addEdgeTo(unsigned LinkNo, const DSNodeHandle &N); + void addEdgeTo(const DSNodeHandle &N) { addEdgeTo(0, N); } + + /// mergeWith - Merge the logical node pointed to by 'this' with the node + /// pointed to by 'N'. + /// + void mergeWith(const DSNodeHandle &N); + + // hasLink - Return true if there is a link at the specified offset... + inline bool hasLink(unsigned Num) const; + + /// getLink - Treat this current node pointer as a pointer to a structure of + /// some sort. This method will return the pointer a mem[this+Num] + /// + inline const DSNodeHandle *getLink(unsigned Num) const; + inline DSNodeHandle *getLink(unsigned Num); + + inline void setLink(unsigned Num, const DSNodeHandle &NH); +}; + + +//===----------------------------------------------------------------------===// +/// DSNode - Data structure node class +/// +/// This class represents an untyped memory object of Size bytes. It keeps +/// track of any pointers that have been stored into the object as well as the +/// different types represented in this object. +/// +class DSNode { + /// Links - Contains one entry for every _distinct_ pointer field in the + /// memory block. These are demand allocated and indexed by the MergeMap + /// vector. + /// + std::vector Links; + + /// MergeMap - Maps from every byte in the object to a signed byte number. + /// This map is neccesary due to the merging that is possible as part of the + /// unification algorithm. To merge two distinct bytes of the object together + /// into a single logical byte, the indexes for the two bytes are set to the + /// same value. This fully general merging is capable of representing all + /// manners of array merging if neccesary. + /// + /// This map is also used to map outgoing pointers to various byte offsets in + /// this data structure node. If this value is >= 0, then it indicates that + /// the numbered entry in the Links vector contains the outgoing edge for this + /// byte offset. In this way, the Links vector can be demand allocated and + /// byte elements of the node may be merged without needing a Link allocated + /// for it. + /// + /// Initially, each each element of the MergeMap is assigned a unique negative + /// number, which are then merged as the unification occurs. + /// + std::vector MergeMap; + + /// Referrers - Keep track of all of the node handles that point to this + /// DSNode. These pointers may need to be updated to point to a different + /// node if this node gets merged with it. + /// + std::vector Referrers; + + /// TypeEntries - As part of the merging process of this algorithm, nodes of + /// different types can be represented by this single DSNode. This vector is + /// kept sorted. + /// + typedef std::pair TypeRec; + std::vector TypeEntries; + + /// Globals - The list of global values that are merged into this node. + /// + std::vector Globals; + + void operator=(const DSNode &); // DO NOT IMPLEMENT +public: + enum NodeTy { + ShadowNode = 0, // Nothing is known about this node... + ScalarNode = 1 << 0, // Scalar of the current function contains this value + AllocaNode = 1 << 1, // This node was allocated with alloca + NewNode = 1 << 2, // This node was allocated with malloc + GlobalNode = 1 << 3, // This node was allocated by a global var decl + Incomplete = 1 << 4, // This node may not be complete + }; + + /// NodeType - A union of the above bits. "Shadow" nodes do not add any flags + /// to the nodes in the data structure graph, so it is possible to have nodes + /// with a value of 0 for their NodeType. Scalar and Alloca markers go away + /// when function graphs are inlined. + /// + unsigned char NodeType; + + DSNode(enum NodeTy NT, const Type *T); + DSNode(const DSNode &); + + ~DSNode() { +#ifndef NDEBUG + dropAllReferences(); // Only needed to satisfy assertion checks... + assert(Referrers.empty() && "Referrers to dead node exist!"); +#endif + } + + // Iterator for graph interface... + typedef DSNodeIterator iterator; + inline iterator begin(); // Defined in DataStructureGraph.h + inline iterator end(); + + //===-------------------------------------------------- + // Accessors + + // getSize - Return the maximum number of bytes occupied by this object... + unsigned getSize() const { return MergeMap.size(); } + + // getTypeEntries - Return the possible types and their offsets in this object + const std::vector &getTypeEntries() const { return TypeEntries; } + + // getReferrers - Return a list of the pointers to this node... + const std::vector &getReferrers() const { return Referrers; } + + + /// hasLink - Return true if this memory object has a link at the specified + /// location. + /// + bool hasLink(unsigned i) const { + assert(i < getSize() && "Field Link index is out of range!"); + return MergeMap[i] >= 0; + } + + DSNodeHandle *getLink(unsigned i) { + if (hasLink(i)) + return &Links[MergeMap[i]]; + return 0; + } + const DSNodeHandle *getLink(unsigned i) const { + if (hasLink(i)) + return &Links[MergeMap[i]]; + return 0; + } + + /// setLink - Set the link at the specified offset to the specified + /// NodeHandle, replacing what was there. It is uncommon to use this method, + /// instead one of the higher level methods should be used, below. + /// + void setLink(unsigned i, const DSNodeHandle &NH); + + /// addEdgeTo - Add an edge from the current node to the specified node. This + /// can cause merging of nodes in the graph. + /// + void addEdgeTo(unsigned Offset, const DSNodeHandle &NH); + + /// mergeWith - Merge this node and the specified node, moving all links to + /// and from the argument node into the current node, deleting the node + /// argument. Offset indicates what offset the specified node is to be merged + /// into the current node. + /// + /// The specified node may be a null pointer (in which case, nothing happens). + /// + void mergeWith(const DSNodeHandle &NH, unsigned Offset); + + /// addGlobal - Add an entry for a global value to the Globals list. This + /// also marks the node with the 'G' flag if it does not already have it. + /// + void addGlobal(GlobalValue *GV); + const std::vector &getGlobals() const { return Globals; } + std::vector &getGlobals() { return Globals; } + + void print(std::ostream &O, const DSGraph *G) const; + void dump() const; + + void dropAllReferences() { + Links.clear(); + } + + /// remapLinks - Change all of the Links in the current node according to the + /// specified mapping. + void remapLinks(std::map &OldNodeMap); + +private: + friend class DSNodeHandle; + // addReferrer - Keep the referrer set up to date... + void addReferrer(DSNodeHandle *H) { Referrers.push_back(H); } + void removeReferrer(DSNodeHandle *H); + + /// rewriteMergeMap - Loop over the mergemap, replacing any references to the + /// index From to be references to the index To. + /// + void rewriteMergeMap(signed char From, signed char To) { + assert(From != To && "Cannot change something into itself!"); + for (unsigned i = 0, e = MergeMap.size(); i != e; ++i) + if (MergeMap[i] == From) + MergeMap[i] = To; + } + + /// mergeMappedValues - This is the higher level form of rewriteMergeMap. It + /// is fully capable of merging links together if neccesary as well as simply + /// rewriting the map entries. + /// + void mergeMappedValues(signed char V1, signed char V2); +}; + + +//===----------------------------------------------------------------------===// +// Define inline DSNodeHandle functions that depend on the definition of DSNode +// + +inline void DSNodeHandle::setNode(DSNode *n) { + if (N) N->removeReferrer(this); + N = n; + if (N) N->addReferrer(this); +} + +inline bool DSNodeHandle::hasLink(unsigned Num) const { + assert(N && "DSNodeHandle does not point to a node yet!"); + return N->hasLink(Num+Offset); +} + + +/// getLink - Treat this current node pointer as a pointer to a structure of +/// some sort. This method will return the pointer a mem[this+Num] +/// +inline const DSNodeHandle *DSNodeHandle::getLink(unsigned Num) const { + assert(N && "DSNodeHandle does not point to a node yet!"); + return N->getLink(Num+Offset); +} +inline DSNodeHandle *DSNodeHandle::getLink(unsigned Num) { + assert(N && "DSNodeHandle does not point to a node yet!"); + return N->getLink(Num+Offset); +} + +inline void DSNodeHandle::setLink(unsigned Num, const DSNodeHandle &NH) { + assert(N && "DSNodeHandle does not point to a node yet!"); + N->setLink(Num+Offset, NH); +} + +/// addEdgeTo - Add an edge from the current node to the specified node. This +/// can cause merging of nodes in the graph. +/// +inline void DSNodeHandle::addEdgeTo(unsigned LinkNo, const DSNodeHandle &Node) { + assert(N && "DSNodeHandle does not point to a node yet!"); + N->addEdgeTo(LinkNo+Offset, Node); +} + +/// mergeWith - Merge the logical node pointed to by 'this' with the node +/// pointed to by 'N'. +/// +inline void DSNodeHandle::mergeWith(const DSNodeHandle &Node) { + assert(N && "DSNodeHandle does not point to a node yet!"); + N->mergeWith(Node, Offset); +} + + +//===----------------------------------------------------------------------===// +/// DSGraph - The graph that represents a function. +/// +class DSGraph { + Function *Func; + std::vector Nodes; + DSNodeHandle RetNode; // Node that gets returned... + std::map ValueMap; + +#if 0 + // GlobalsGraph -- Reference to the common graph of globally visible objects. + // This includes GlobalValues, New nodes, Cast nodes, and Calls. + // + GlobalDSGraph* GlobalsGraph; +#endif + + // FunctionCalls - This vector maintains a single entry for each call + // instruction in the current graph. Each call entry contains DSNodeHandles + // that refer to the arguments that are passed into the function call. The + // first entry in the vector is the scalar that holds the return value for the + // call, the second is the function scalar being invoked, and the rest are + // pointer arguments to the function. + // + std::vector > FunctionCalls; + +#if 0 + // OrigFunctionCalls - This vector retains a copy of the original function + // calls of the current graph. This is needed to support top-down inlining + // after bottom-up inlining is complete, since the latter deletes call nodes. + // + std::vector > OrigFunctionCalls; + + // PendingCallers - This vector records all unresolved callers of the + // current function, i.e., ones whose graphs have not been inlined into + // the current graph. As long as there are unresolved callers, the nodes + // for formal arguments in the current graph cannot be eliminated, and + // nodes in the graph reachable from the formal argument nodes or + // global variable nodes must be considered incomplete. + std::set PendingCallers; +#endif + +protected: + +#if 0 + // clone all the call nodes and save the copies in OrigFunctionCalls + void saveOrigFunctionCalls() { + assert(OrigFunctionCalls.size() == 0 && "Do this only once!"); + OrigFunctionCalls = FunctionCalls; + } + + // get the saved copies of the original function call nodes + std::vector > &getOrigFunctionCalls() { + return OrigFunctionCalls; + } +#endif + + void operator=(const DSGraph &); // DO NOT IMPLEMENT +public: + DSGraph() : Func(0) {} // Create a new, empty, DSGraph. + DSGraph(Function &F); // Compute the local DSGraph + DSGraph(const DSGraph &DSG); // Copy ctor + ~DSGraph(); + + bool hasFunction() const { return Func != 0; } + Function &getFunction() const { return *Func; } + + /// getNodes - Get a vector of all the nodes in the graph + /// + const std::vector &getNodes() const { return Nodes; } + std::vector &getNodes() { return Nodes; } + + /// addNode - Add a new node to the graph. + /// + void addNode(DSNode *N) { Nodes.push_back(N); } + + /// getValueMap - Get a map that describes what the nodes the scalars in this + /// function point to... + /// + std::map &getValueMap() { return ValueMap; } + const std::map &getValueMap() const { return ValueMap;} + + std::vector > &getFunctionCalls() { + return FunctionCalls; + } + const std::vector > &getFunctionCalls() const { + return FunctionCalls; + } + + const DSNodeHandle &getRetNode() const { return RetNode; } + DSNodeHandle &getRetNode() { return RetNode; } + + unsigned getGraphSize() const { + return Nodes.size(); + } + + void print(std::ostream &O) const; + void dump() const; + void writeGraphToFile(std::ostream &O, const std::string &GraphName); + + // maskNodeTypes - Apply a mask to all of the node types in the graph. This + // is useful for clearing out markers like Scalar or Incomplete. + // + void maskNodeTypes(unsigned char Mask); + void maskIncompleteMarkers() { maskNodeTypes(~DSNode::Incomplete); } + + // markIncompleteNodes - Traverse the graph, identifying nodes that may be + // modified by other functions that have not been resolved yet. This marks + // nodes that are reachable through three sources of "unknownness": + // Global Variables, Function Calls, and Incoming Arguments + // + // For any node that may have unknown components (because something outside + // the scope of current analysis may have modified it), the 'Incomplete' flag + // is added to the NodeType. + // + void markIncompleteNodes(bool markFormalArgs = true); + + // removeTriviallyDeadNodes - After the graph has been constructed, this + // method removes all unreachable nodes that are created because they got + // merged with other nodes in the graph. + // + void removeTriviallyDeadNodes(bool KeepAllGlobals = false); + + // removeDeadNodes - Use a more powerful reachability analysis to eliminate + // subgraphs that are unreachable. This often occurs because the data + // structure doesn't "escape" into it's caller, and thus should be eliminated + // from the caller's graph entirely. This is only appropriate to use when + // inlining graphs. + // + void removeDeadNodes(bool KeepAllGlobals = false, bool KeepCalls = true); + +#if 0 + // AddCaller - add a known caller node into the graph and mark it pending. + // getCallers - get a vector of the functions that call this one + // getCallersPending - get a matching vector of bools indicating if each + // caller's DSGraph has been resolved into this one. + // + void addCaller(Function &caller) { + PendingCallers.insert(&caller); + } + std::set &getPendingCallers() { + return PendingCallers; + } +#endif + + // cloneInto - Clone the specified DSGraph into the current graph, returning + // the Return node of the graph. The translated ValueMap for the old function + // is filled into the OldValMap member. + // If StripScalars (StripAllocas) is set to true, Scalar (Alloca) markers + // are removed from the graph as the graph is being cloned. + // If CopyCallers is set to true, the PendingCallers list is copied. + // If CopyOrigCalls is set to true, the OrigFunctionCalls list is copied. + // + DSNodeHandle cloneInto(const DSGraph &G, + std::map &OldValMap, + std::map &OldNodeMap, + bool StripScalars = false, bool StripAllocas = false, + bool CopyCallers = true, bool CopyOrigCalls = true); + +#if 0 + // cloneGlobalInto - Clone the given global node (or the node for the given + // GlobalValue) from the GlobalsGraph and all its target links (recursively). + // + DSNode* cloneGlobalInto(const DSNode* GNode); + DSNode* cloneGlobalInto(GlobalValue* GV) { + assert(!GV || (((DSGraph*) GlobalsGraph)->ValueMap[GV] != 0)); + return GV? cloneGlobalInto(((DSGraph*) GlobalsGraph)->ValueMap[GV]) : 0; + } +#endif + +private: + bool isNodeDead(DSNode *N); +}; + +#endif