C#: Expose synthetic globals for use in C#, allow printing of summaries that uses synthetic globals.

Author: michaelnebel

csharp/ql/lib/semmle/code/csharp/dataflow/FlowSummary.qll

@@ -72,6 +72,10 @@ module SummaryComponent {
           jrk.getTargetReturnKind() instanceof DataFlowDispatch::NormalReturnKind
         ))
   }
+
+  predicate syntheticGlobal = SummaryComponentInternal::syntheticGlobal/1;
+
+  class SyntheticGlobal = SummaryComponentInternal::SyntheticGlobal;
 }
 
 class SummaryComponentStack = Impl::Public::SummaryComponentStack;

csharp/ql/lib/semmle/code/csharp/dataflow/internal/FlowSummaryImpl.qll

@@ -180,6 +180,11 @@ module Public {
       result = "Argument[" + getParameterPosition(pos) + "]"
     )
     or
+    exists(string synthetic |
+      sc = TSyntheticGlobalSummaryComponent(synthetic) and
+      result = "SyntheticGlobal[" + synthetic + "]"
+    )
+    or
     sc = TReturnSummaryComponent(getReturnValueKind()) and result = "ReturnValue"
   }
 

csharp/ql/lib/semmle/code/csharp/dataflow/internal/FlowSummaryImplSpecific.qll

@@ -19,6 +19,13 @@ class SummarizedCallableBase extends Callable {
   SummarizedCallableBase() { this.isUnboundDeclaration() }
 }
 
+/**
+ * A module for importing frameworks that define synthetic globals.
+ */
+private module SyntheticGlobals {
+  private import semmle.code.csharp.frameworks.EntityFramework
+}
+
 DataFlowCallable inject(SummarizedCallable c) { result.asSummarizedCallable() = c }
 
 /** Gets the parameter position of the instance parameter. */