Update edge removal API in call graph.

Add a parameter for a function the call site is in, rather than using
the call site to determine the function.

This is necessary for enabling invalidation of call graph information
for individual functions. If we're not maintaining the call graph during
a pass, we may delete an instruction and be left with a dangling pointer
in the call graph edge. This allows us to still remove the edge properly
without trying to look at the instruction it represents.

include/swift/SILAnalysis/CallGraph.h

@@ -454,7 +454,7 @@ class CallGraph {
   /// caller or callee edges.
   void removeNode(CallGraphNode *Node);
 
-  void removeEdge(CallGraphEdge *Edge);
+  void removeEdgeFromFunction(CallGraphEdge *Edge, SILFunction *F);
   void removeEdgesForApply(FullApplySite AI);
 
   // Query funtions for getting nodes and edges from the call graph.
@@ -586,7 +586,7 @@ class CallGraphEditor {
     if (CG) {
       if (auto AI = FullApplySite::isa(I))
         if (auto *Edge = CG->tryGetCallGraphEdge(AI))
-          CG->removeEdge(Edge);
+          CG->removeEdgeFromFunction(Edge, I->getFunction());
     }
   }
 

lib/SILAnalysis/CallGraph.cpp

@@ -355,18 +355,18 @@ void CallGraph::addEdgesForApply(FullApplySite Apply,
   ++NumAppliesWithEdges;
 }
 
-void CallGraph::removeEdge(CallGraphEdge *Edge) {
+void CallGraph::removeEdgeFromFunction(CallGraphEdge *Edge, SILFunction *F) {
   // Remove the edge from all the potential callee call graph nodes.
   auto CalleeSet = Edge->getCalleeSet();
   for (auto *CalleeNode : CalleeSet)
     CalleeNode->removeCallerEdge(Edge);
 
   // Remove the edge from the caller's call graph node.
-  auto Apply = Edge->getApply();
-  auto *CallerNode = getCallGraphNode(Apply.getFunction());
+  auto *CallerNode = getCallGraphNode(F);
   CallerNode->removeCalleeEdge(Edge);
 
   // Remove the mapping from the apply to this edge.
+  auto Apply = Edge->getApply();
   ApplyToEdgeMap.erase(Apply);
 
   // Call the destructor for the edge. The memory will be reclaimed
@@ -398,7 +398,7 @@ void CallGraph::removeNode(CallGraphNode *Node) {
 // apply is known to the call graph.
 void CallGraph::removeEdgesForApply(FullApplySite AI) {
   assert(ApplyToEdgeMap.count(AI) && "Expected apply to be in edge map!");
-  removeEdge(ApplyToEdgeMap[AI]);
+  removeEdgeFromFunction(ApplyToEdgeMap[AI], AI.getFunction());
 }
 
 void CallGraph::addEdges(SILFunction *F) {
@@ -777,7 +777,7 @@ void CallGraphEditor::replaceApplyWithNew(FullApplySite Old,
     return;
 
   if (auto *Edge = CG->tryGetCallGraphEdge(Old))
-    CG->removeEdge(Edge);
+    CG->removeEdgeFromFunction(Edge, Old.getFunction());
 
   CG->addEdgesForApply(New);
 }
@@ -788,7 +788,7 @@ void CallGraphEditor::replaceApplyWithNew(FullApplySite Old,
     return;
 
   if (auto *Edge = CG->tryGetCallGraphEdge(Old))
-    CG->removeEdge(Edge);
+    CG->removeEdgeFromFunction(Edge, Old.getFunction());
 
   for (auto NewApply : NewApplies)
     CG->addEdgesForApply(NewApply);
@@ -813,7 +813,7 @@ void CallGraphEditor::removeAllCalleeEdgesFrom(SILFunction *F) {
   auto &CalleeEdges = CG->getCallGraphNode(F)->getCalleeEdges();
   while (!CalleeEdges.empty()) {
     auto *Edge = *CalleeEdges.begin();
-    CG->removeEdge(Edge);
+    CG->removeEdgeFromFunction(Edge, F);
   }
 }