fixed bugs in control-flow generation

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>

src/cc/frontends/p4/compiler/ebpfProgram.py

@@ -483,12 +483,10 @@ class EbpfProgram(object):
         done = set()
         while len(nodestoadd) > 0:
             todo = nodestoadd.pop()
-            if todo is None:
-                todo = nextEntryPoint
-            if todo is None:
-                continue
             if todo in done:
                 continue
+            if todo is None:
+                continue
 
             print("Generating ", todo.name)
 
@@ -503,3 +501,6 @@ class EbpfProgram(object):
         for e in self.entryPoints:
             todo.add(e)
         self.generatePipelineInternal(serializer, todo, self.egressEntry)
+        todo = set()
+        todo.add(self.egressEntry)
+        self.generatePipelineInternal(serializer, todo, None)

src/cc/frontends/p4/compiler/ebpfTable.py

@@ -365,6 +365,12 @@ class EbpfTable(object):
             serializer.newline()
 
         serializer.blockEnd(True)
+        if not "hit" in nextNode:
+            # Catch-all
+            serializer.emitIndent()
+            serializer.appendFormat("goto end;")
+            serializer.newline()
+
         serializer.blockEnd(True)
 
     def runAction(self, serializer, tableName, valueName, program, nextNode):

src/cc/frontends/p4/compiler/topoSorting.py

@@ -86,4 +86,3 @@ class Graph(object):
             return None
 
         return topo_sorting
-