[LCG] Add the most basic of edge insertion to the lazy call graph. This

just handles the pre-DFS case. Also add some test cases for this case to
make sure it works.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207411 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 15 insertions, 0 deletions

diff --git a/lib/Analysis/LazyCallGraph.cpp b/lib/Analysis/LazyCallGraph.cpp
index b593069e66..05757e1e2f 100644
--- a/lib/Analysis/LazyCallGraph.cpp
+++ b/lib/Analysis/LazyCallGraph.cpp
@@ -75,6 +75,14 @@ LazyCallGraph::Node::Node(LazyCallGraph &G, Function &F)
   findCallees(Worklist, Visited, Callees, CalleeIndexMap);
 }
 
+void LazyCallGraph::Node::insertEdgeInternal(Function &Callee) {
+  CalleeIndexMap.insert(std::make_pair(&Callee, Callees.size()));
+  if (Node *N = G->lookup(Callee))
+    Callees.push_back(N);
+  else
+    Callees.push_back(&Callee);
+}
+
 void LazyCallGraph::Node::removeEdgeInternal(Function &Callee) {
   auto IndexMapI = CalleeIndexMap.find(&Callee);
   assert(IndexMapI != CalleeIndexMap.end() &&
@@ -353,6 +361,13 @@ LazyCallGraph::SCC::removeIntraSCCEdge(Node &CallerN,
   return ResultSCCs;
 }
 
+void LazyCallGraph::insertEdge(Node &CallerN, Function &Callee) {
+  assert(SCCMap.empty() && DFSStack.empty() &&
+         "This method cannot be called after SCCs have been formed!");
+
+  return CallerN.insertEdgeInternal(Callee);
+}
+
 void LazyCallGraph::removeEdge(Node &CallerN, Function &Callee) {
   assert(SCCMap.empty() && DFSStack.empty() &&
          "This method cannot be called after SCCs have been formed!");