C++: Add an 'EdgeKind' column to 'getExceptionSuccessorInstruction'.

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedElement.qll

@@ -914,10 +914,10 @@ abstract class TranslatedElement extends TTranslatedElement {
    * Gets the instruction to which control should flow if an exception is thrown
    * within this element. This will generally return first `catch` block of the
    * nearest enclosing `try`, or the `Unwind` instruction for the function if
-   * there is no enclosing `try`.
+   * there is no enclosing `try`. The successor edge kind is specified by `kind`.
    */
-  Instruction getExceptionSuccessorInstruction() {
-    result = this.getParent().getExceptionSuccessorInstruction()
+  Instruction getExceptionSuccessorInstruction(EdgeKind kind) {
+    result = this.getParent().getExceptionSuccessorInstruction(kind)
   }
 
   /**

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedExpr.qll

@@ -2566,7 +2566,7 @@ abstract class TranslatedThrowExpr extends TranslatedNonConstantExpr {
   override Instruction getInstructionSuccessor(InstructionTag tag, EdgeKind kind) {
     tag = ThrowTag() and
     kind instanceof ExceptionEdge and
-    result = this.getParent().getExceptionSuccessorInstruction()
+    result = this.getParent().getExceptionSuccessorInstruction(any(GotoEdge edge))
   }
 
   override Instruction getResult() { none() }

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedFunction.qll

@@ -222,8 +222,9 @@ class TranslatedFunction extends TranslatedRootElement, TTranslatedFunction {
     )
   }
 
-  final override Instruction getExceptionSuccessorInstruction() {
-    result = this.getInstruction(UnwindTag())
+  final override Instruction getExceptionSuccessorInstruction(EdgeKind kind) {
+    result = this.getInstruction(UnwindTag()) and
+    kind instanceof GotoEdge
   }
 
   final override Instruction getInstructionRegisterOperand(InstructionTag tag, OperandTag operandTag) {

cpp/ql/lib/semmle/code/cpp/ir/implementation/raw/internal/TranslatedStmt.qll

@@ -563,13 +563,12 @@ class TranslatedTryStmt extends TranslatedStmt {
     // The last catch clause flows to the exception successor of the parent
     // of the `try`, because the exception successor of the `try` itself is
     // the first catch clause.
-    kind instanceof GotoEdge and
     handler = this.getHandler(stmt.getNumberOfCatchClauses() - 1) and
-    result = this.getParent().getExceptionSuccessorInstruction()
+    result = this.getParent().getExceptionSuccessorInstruction(kind)
   }
 
-  final override Instruction getExceptionSuccessorInstruction() {
-    result = this.getHandler(0).getFirstInstruction(any(GotoEdge edge))
+  final override Instruction getExceptionSuccessorInstruction(EdgeKind kind) {
+    result = this.getHandler(0).getFirstInstruction(kind)
   }
 
   private TranslatedElement getHandler(int index) { result = stmt.getTranslatedHandler(index) }
@@ -635,10 +634,10 @@ abstract class TranslatedHandler extends TranslatedStmt {
     child = this.getBlock() and result = this.getParent().getChildSuccessor(this, kind)
   }
 
-  override Instruction getExceptionSuccessorInstruction() {
+  override Instruction getExceptionSuccessorInstruction(EdgeKind kind) {
     // A throw from within a `catch` block flows to the handler for the parent of
     // the `try`.
-    result = this.getParent().getParent().getExceptionSuccessorInstruction()
+    result = this.getParent().getParent().getExceptionSuccessorInstruction(kind)
   }
 
   TranslatedStmt getBlock() { result = getTranslatedStmt(stmt.getBlock()) }