New implementation of data structure analysis. Only local analysis has been

implemented so far.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2871 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 92 insertions, 130 deletions

diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp
index 7575a5da5b..84e2cfbc47 100644
--- a/lib/Analysis/DataStructure/DataStructure.cpp
+++ b/lib/Analysis/DataStructure/DataStructure.cpp
@@ -1,165 +1,127 @@
-//===- DataStructure.cpp - Analysis for data structure identification -------=//
+//===- DataStructure.cpp - Implement the core data structure analysis -----===//
 //
-// Implement the LLVM data structure analysis library.
+// This file implements the core data structure functionality.
 //
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Analysis/DataStructure.h"
 #include "llvm/Module.h"
-#include <fstream>
+#include "llvm/DerivedTypes.h"
 #include <algorithm>
+#include "Support/STLExtras.h"
 
-//===----------------------------------------------------------------------===//
-// DataStructure Class Implementation
-//
+AnalysisID LocalDataStructures::ID(AnalysisID::create<LocalDataStructures>());
 
-AnalysisID DataStructure::ID(AnalysisID::create<DataStructure>());
+//===----------------------------------------------------------------------===//
+// DSNode Implementation
+//===----------------------------------------------------------------------===//
 
-// releaseMemory - If the pass pipeline is done with this pass, we can release
-// our memory... here...
-void DataStructure::releaseMemory() {
-  for (InfoMap::iterator I = DSInfo.begin(), E = DSInfo.end(); I != E; ++I) {
-    delete I->second.first;
-    delete I->second.second;
+DSNode::DSNode(enum NodeTy NT, const Type *T) : Ty(T), NodeType(NT) {
+  // If this node has any fields, allocate them now, but leave them null.
+  switch (T->getPrimitiveID()) {
+  case Type::PointerTyID: Links.resize(1); break;
+  case Type::ArrayTyID:   Links.resize(1); break;
+  case Type::StructTyID:
+    Links.resize(cast<StructType>(T)->getNumContainedTypes());
+    break;
+  default: break;
   }
+}
 
-  // Empty map so next time memory is released, data structures are not
-  // re-deleted.
-  DSInfo.clear();
+void DSNode::removeReferrer(DSNodeHandle *H) {
+  // Search backwards, because we depopulate the list from the back for
+  // efficiency (because it's a vector).
+  std::vector<DSNodeHandle*>::reverse_iterator I =
+    std::find(Referrers.rbegin(), Referrers.rend(), H);
+  assert(I != Referrers.rend() && "Referrer not pointing to node!");
+  Referrers.erase(I.base()-1);
 }
 
-// FIXME REMOVE
-#include <sys/time.h>
-#include "Support/CommandLine.h"
-
-cl::Flag   Time("t", "Print analysis time...");
-
-
-// print - Print out the analysis results...
-void DataStructure::print(std::ostream &O, Module *M) const {
-  if (Time) {
-    timeval TV1, TV2;
-    gettimeofday(&TV1, 0);
-    for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
-      if (!I->isExternal() && I->getName() == "main") {
-        //getDSGraph(*I);
-        getClosedDSGraph(I);
-      }
-    gettimeofday(&TV2, 0);
-    std::cerr << "Analysis took "
-         << (TV2.tv_sec-TV1.tv_sec)*1000000+(TV2.tv_usec-TV1.tv_usec)
-         << " microseconds.\n";
+// addEdgeTo - Add an edge from the current node to the specified node.  This
+// can cause merging of nodes in the graph.
+//
+void DSNode::addEdgeTo(unsigned LinkNo, DSNode *N) {
+  assert(LinkNo < Links.size() && "LinkNo out of range!");
+  if (N == 0 || Links[LinkNo] == N) return;  // Nothing to do
+  if (Links[LinkNo] == 0) {                  // No merging to perform
+    Links[LinkNo] = N;
+    return;
   }
 
-  for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
-    if (!I->isExternal()) {
-
-      std::string Filename = "ds." + I->getName() + ".dot";
-      O << "Writing '" << Filename << "'...";
-      std::ofstream F(Filename.c_str());
-
-      if (F.good()) {
-        F << "digraph DataStructures {\n"
-          << "\tnode [shape=Mrecord];\n"
-          << "\tedge [arrowtail=\"dot\"];\n"
-          << "\tsize=\"10,7.5\";\n"
-          << "\trotate=\"90\";\n";
-
-        getDSGraph(I).printFunction(F, "Local");
-        getClosedDSGraph(I).printFunction(F, "Closed");
-
-        F << "}\n";
-      } else {
-        O << "  error opening file for writing!\n";
-      }
-
-      if (Time) 
-        O << " [" << getDSGraph(I).getGraphSize() << ", "
-          << getClosedDSGraph(I).getGraphSize() << "]\n";
-      else
-        O << "\n";
-    }
+  // Merge the two nodes...
+  Links[LinkNo]->mergeWith(N);
 }
 
 
-//===----------------------------------------------------------------------===//
-// PointerVal Class Implementation
+// mergeWith - Merge this node into the specified node, moving all links to and
+// from the argument node into the current node.  The specified node may be a
+// null pointer (in which case, nothing happens).
 //
-
-void PointerVal::print(std::ostream &O) const {
-  if (Node) {
-    O << "  Node: " << Node->getCaption() << "[" << Index << "]\n";
-  } else {
-    O << "  NULL NODE\n";
+void DSNode::mergeWith(DSNode *N) {
+  if (N == 0 || N == this) return;  // Noop
+  assert(N->Ty == Ty && N->Links.size() == Links.size() &&
+         "Cannot merge nodes of two different types!");
+
+  // Remove all edges pointing at N, causing them to point to 'this' instead.
+  while (!N->Referrers.empty())
+    *N->Referrers.back() = this;
+
+  // Make all of the outgoing links of N now be outgoing links of this.  This
+  // can cause recursive merging!
+  //
+  for (unsigned i = 0, e = Links.size(); i != e; ++i) {
+    addEdgeTo(i, N->Links[i]);
+    N->Links[i] = 0;  // Reduce unneccesary edges in graph. N is dead
   }
-}
-
-//===----------------------------------------------------------------------===//
-// PointerValSet Class Implementation
-//
 
-void PointerValSet::addRefs() {
-  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
-    Vals[i].Node->addReferrer(this);
+  NodeType |= N->NodeType;
+  N->NodeType = 0;   // N is now a dead node.
 }
 
-void PointerValSet::dropRefs() {
-  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
-    Vals[i].Node->removeReferrer(this);
-}
-
-const PointerValSet &PointerValSet::operator=(const PointerValSet &PVS) {
-  dropRefs();
-  Vals.clear();
-  Vals = PVS.Vals;
-  addRefs();
-  return *this;
-}
-
-// operator< - Allow insertion into a map...
-bool PointerValSet::operator<(const PointerValSet &PVS) const {
-  if (Vals.size() < PVS.Vals.size()) return true;
-  if (Vals.size() > PVS.Vals.size()) return false;
-  if (Vals.size() == 1) return Vals[0] < PVS.Vals[0];  // Most common case
+//===----------------------------------------------------------------------===//
+// DSGraph Implementation
+//===----------------------------------------------------------------------===//
 
-  std::vector<PointerVal> S1(Vals), S2(PVS.Vals);
-  sort(S1.begin(), S1.end());
-  sort(S2.begin(), S2.end());
-  return S1 < S2;
-}
+DSGraph::~DSGraph() {
+  FunctionCalls.clear();
+  ValueMap.clear();
+  RetNode = 0;
 
-bool PointerValSet::operator==(const PointerValSet &PVS) const {
-  if (Vals.size() != PVS.Vals.size()) return false;
-  if (Vals.size() == 1) return Vals[0] == PVS.Vals[0];  // Most common case...
+#ifndef NDEBUG
+  // Drop all intra-node references, so that assertions don't fail...
+  std::for_each(Nodes.begin(), Nodes.end(),
+                std::mem_fun(&DSNode::dropAllReferences));
+#endif
 
-  std::vector<PointerVal> S1(Vals), S2(PVS.Vals);
-  sort(S1.begin(), S1.end());
-  sort(S2.begin(), S2.end());
-  return S1 == S2;
+  // Delete all of the nodes themselves...
+  std::for_each(Nodes.begin(), Nodes.end(), deleter<DSNode>);
 }
 
+//===----------------------------------------------------------------------===//
+// LocalDataStructures Implementation
+//===----------------------------------------------------------------------===//
 
-bool PointerValSet::add(const PointerVal &PV, Value *Pointer) {
-  if (std::find(Vals.begin(), Vals.end(), PV) != Vals.end())
-    return false;
-  Vals.push_back(PV);
-  if (Pointer) PV.Node->addPointer(Pointer);
-  PV.Node->addReferrer(this);
-  return true;
-}
+// releaseMemory - If the pass pipeline is done with this pass, we can release
+// our memory... here...
+//
+void LocalDataStructures::releaseMemory() {
+  for (std::map<Function*, DSGraph*>::iterator I = DSInfo.begin(),
+         E = DSInfo.end(); I != E; ++I)
+    delete I->second;
 
-// removePointerTo - Remove a single pointer val that points to the specified
-// node...
-void PointerValSet::removePointerTo(DSNode *Node) {
-  std::vector<PointerVal>::iterator I = std::find(Vals.begin(), Vals.end(), Node);
-  assert(I != Vals.end() && "Couldn't remove nonexistent edge!");
-  Vals.erase(I);
-  Node->removeReferrer(this);
+  // Empty map so next time memory is released, data structures are not
+  // re-deleted.
+  DSInfo.clear();
 }
 
+bool LocalDataStructures::run(Module &M) {
+  // Calculate all of the graphs...
+  for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
+    if (!I->isExternal()) {
+      std::map<Function*, DSGraph*>::iterator DI = DSInfo.find(I);
+      if (DI == DSInfo.end() || DI->second == 0)
+        DSInfo.insert(std::make_pair(&*I, new DSGraph(*I)));
+    }
 
-void PointerValSet::print(std::ostream &O) const {
-  for (unsigned i = 0, e = Vals.size(); i != e; ++i)
-    Vals[i].print(O);
+  return false;
 }
-