1 files changed, 241 insertions, 0 deletions
diff --git a/lib/Analysis/ExplodedGraph.cpp b/lib/Analysis/ExplodedGraph.cpp
new file mode 100644
index 0000000..20de6c4
--- /dev/null
+++ b/lib/Analysis/ExplodedGraph.cpp
@@ -0,0 +1,241 @@
+//=-- ExplodedGraph.cpp - Local, Path-Sens. "Exploded Graph" -*- C++ -*------=//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines the template classes ExplodedNode and ExplodedGraph,
+//  which represent a path-sensitive, intra-procedural "exploded graph."
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/PathSensitive/ExplodedGraph.h"
+#include "clang/AST/Stmt.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+#include <vector>
+
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// Node auditing.
+//===----------------------------------------------------------------------===//
+
+// An out of line virtual method to provide a home for the class vtable.
+ExplodedNodeImpl::Auditor::~Auditor() {}
+
+#ifndef NDEBUG
+static ExplodedNodeImpl::Auditor* NodeAuditor = 0;
+#endif
+
+void ExplodedNodeImpl::SetAuditor(ExplodedNodeImpl::Auditor* A) {
+#ifndef NDEBUG
+  NodeAuditor = A;
+#endif
+}
+
+//===----------------------------------------------------------------------===//
+// ExplodedNodeImpl.
+//===----------------------------------------------------------------------===//
+
+static inline std::vector<ExplodedNodeImpl*>& getVector(void* P) {
+  return *reinterpret_cast<std::vector<ExplodedNodeImpl*>*>(P);
+}
+
+void ExplodedNodeImpl::addPredecessor(ExplodedNodeImpl* V) {
+  assert (!V->isSink());
+  Preds.addNode(V);
+  V->Succs.addNode(this);
+#ifndef NDEBUG
+  if (NodeAuditor) NodeAuditor->AddEdge(V, this);
+#endif
+}
+
+void ExplodedNodeImpl::NodeGroup::addNode(ExplodedNodeImpl* N) {
+  
+  assert ((reinterpret_cast<uintptr_t>(N) & Mask) == 0x0);
+  assert (!getFlag());
+  
+  if (getKind() == Size1) {
+    if (ExplodedNodeImpl* NOld = getNode()) {
+      std::vector<ExplodedNodeImpl*>* V = new std::vector<ExplodedNodeImpl*>();
+      assert ((reinterpret_cast<uintptr_t>(V) & Mask) == 0x0);
+      V->push_back(NOld);
+      V->push_back(N);
+      P = reinterpret_cast<uintptr_t>(V) | SizeOther;
+      assert (getPtr() == (void*) V);
+      assert (getKind() == SizeOther);
+    }
+    else {
+      P = reinterpret_cast<uintptr_t>(N);
+      assert (getKind() == Size1);
+    }
+  }
+  else {
+    assert (getKind() == SizeOther);
+    getVector(getPtr()).push_back(N);
+  }
+}
+
+
+unsigned ExplodedNodeImpl::NodeGroup::size() const {
+  if (getFlag())
+    return 0;
+  
+  if (getKind() == Size1)
+    return getNode() ? 1 : 0;
+  else
+    return getVector(getPtr()).size();
+}
+
+ExplodedNodeImpl** ExplodedNodeImpl::NodeGroup::begin() const {
+  if (getFlag())
+    return NULL;
+  
+  if (getKind() == Size1)
+    return (ExplodedNodeImpl**) (getPtr() ? &P : NULL);
+  else
+    return const_cast<ExplodedNodeImpl**>(&*(getVector(getPtr()).begin()));
+}
+
+ExplodedNodeImpl** ExplodedNodeImpl::NodeGroup::end() const {
+  if (getFlag())
+    return NULL;
+  
+  if (getKind() == Size1)
+    return (ExplodedNodeImpl**) (getPtr() ? &P+1 : NULL);
+  else {
+    // Dereferencing end() is undefined behaviour. The vector is not empty, so
+    // we can dereference the last elem and then add 1 to the result.
+    return const_cast<ExplodedNodeImpl**>(&getVector(getPtr()).back()) + 1;
+  }
+}
+
+ExplodedNodeImpl::NodeGroup::~NodeGroup() {
+  if (getKind() == SizeOther) delete &getVector(getPtr());
+}
+
+ExplodedGraphImpl*
+ExplodedGraphImpl::Trim(const ExplodedNodeImpl* const* BeginSources,
+                        const ExplodedNodeImpl* const* EndSources,
+                        InterExplodedGraphMapImpl* M,
+                        llvm::DenseMap<const void*, const void*> *InverseMap) 
+const {
+  
+  typedef llvm::DenseSet<const ExplodedNodeImpl*> Pass1Ty;
+  Pass1Ty Pass1;
+  
+  typedef llvm::DenseMap<const ExplodedNodeImpl*, ExplodedNodeImpl*> Pass2Ty;
+  Pass2Ty& Pass2 = M->M;
+  
+  llvm::SmallVector<const ExplodedNodeImpl*, 10> WL1, WL2;
+
+  // ===- Pass 1 (reverse DFS) -===
+  for (const ExplodedNodeImpl* const* I = BeginSources; I != EndSources; ++I) {
+    assert(*I);
+    WL1.push_back(*I);
+  }
+    
+  // Process the first worklist until it is empty.  Because it is a std::list
+  // it acts like a FIFO queue.
+  while (!WL1.empty()) {
+    const ExplodedNodeImpl *N = WL1.back();
+    WL1.pop_back();
+    
+    // Have we already visited this node?  If so, continue to the next one.
+    if (Pass1.count(N))
+      continue;
+
+    // Otherwise, mark this node as visited.
+    Pass1.insert(N);
+    
+    // If this is a root enqueue it to the second worklist.
+    if (N->Preds.empty()) {
+      WL2.push_back(N);
+      continue;
+    }
+      
+    // Visit our predecessors and enqueue them.
+    for (ExplodedNodeImpl** I=N->Preds.begin(), **E=N->Preds.end(); I!=E; ++I)
+      WL1.push_back(*I);
+  }
+  
+  // We didn't hit a root? Return with a null pointer for the new graph.
+  if (WL2.empty())
+    return 0;
+
+  // Create an empty graph.
+  ExplodedGraphImpl* G = MakeEmptyGraph();
+  
+  // ===- Pass 2 (forward DFS to construct the new graph) -===  
+  while (!WL2.empty()) {
+    const ExplodedNodeImpl* N = WL2.back();
+    WL2.pop_back();
+    
+    // Skip this node if we have already processed it.
+    if (Pass2.find(N) != Pass2.end())
+      continue;
+    
+    // Create the corresponding node in the new graph and record the mapping
+    // from the old node to the new node.
+    ExplodedNodeImpl* NewN = G->getNodeImpl(N->getLocation(), N->State, NULL);
+    Pass2[N] = NewN;
+    
+    // Also record the reverse mapping from the new node to the old node.
+    if (InverseMap) (*InverseMap)[NewN] = N;
+    
+    // If this node is a root, designate it as such in the graph.
+    if (N->Preds.empty())
+      G->addRoot(NewN);
+    
+    // In the case that some of the intended predecessors of NewN have already
+    // been created, we should hook them up as predecessors.
+
+    // Walk through the predecessors of 'N' and hook up their corresponding
+    // nodes in the new graph (if any) to the freshly created node.
+    for (ExplodedNodeImpl **I=N->Preds.begin(), **E=N->Preds.end(); I!=E; ++I) {
+      Pass2Ty::iterator PI = Pass2.find(*I);
+      if (PI == Pass2.end())
+        continue;
+      
+      NewN->addPredecessor(PI->second);
+    }
+
+    // In the case that some of the intended successors of NewN have already
+    // been created, we should hook them up as successors.  Otherwise, enqueue
+    // the new nodes from the original graph that should have nodes created
+    // in the new graph.
+    for (ExplodedNodeImpl **I=N->Succs.begin(), **E=N->Succs.end(); I!=E; ++I) {
+      Pass2Ty::iterator PI = Pass2.find(*I);      
+      if (PI != Pass2.end()) {
+        PI->second->addPredecessor(NewN);
+        continue;
+      }
+
+      // Enqueue nodes to the worklist that were marked during pass 1.
+      if (Pass1.count(*I))
+        WL2.push_back(*I);
+    }
+    
+    // Finally, explictly mark all nodes without any successors as sinks.
+    if (N->isSink())
+      NewN->markAsSink();
+  }
+    
+  return G;
+}
+
+ExplodedNodeImpl*
+InterExplodedGraphMapImpl::getMappedImplNode(const ExplodedNodeImpl* N) const {
+  llvm::DenseMap<const ExplodedNodeImpl*, ExplodedNodeImpl*>::iterator I =
+    M.find(N);
+
+  return I == M.end() ? 0 : I->second;
+}
+
+InterExplodedGraphMapImpl::InterExplodedGraphMapImpl() {}
+