C++: Use SEH exception edges in IR and generate SEH exception edges for calls in __try blocks

cpp/ql/lib/change-notes/2014-12-13-deprecate-throwing.md

@@ -0,0 +1,4 @@
+---
+category: deprecated
+---
+* The `ThrowingFunction` class (`semmle.code.cpp.models.interfaces.Throwing`) has been deprecated. Please use the `AlwaysSehThrowingFunction` class instead.

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

@@ -84,11 +84,10 @@ abstract class TranslatedCall extends TranslatedExpr {
           this.getEnclosingFunction().getFunction() = instr.getEnclosingFunction()
         )
     else (
-      not this.mustThrowException() and
+      not this.mustThrowException(_) and
       result = this.getParent().getChildSuccessor(this, kind)
       or
-      this.mayThrowException() and
-      kind instanceof CppExceptionEdge and
+      this.mayThrowException(kind) and
       result = this.getParent().getExceptionSuccessorInstruction(any(GotoEdge edge))
     )
   }
@@ -117,14 +116,14 @@ abstract class TranslatedCall extends TranslatedExpr {
   final override Instruction getResult() { result = this.getInstruction(CallTag()) }
 
   /**
-   * Holds if the evaluation of this call may throw an exception.
+   * Holds if the evaluation of this call may throw an exception of the kind represented by the `ExceptionEdge`.
    */
-  abstract predicate mayThrowException();
+  abstract predicate mayThrowException(ExceptionEdge e);
 
   /**
-   * Holds if the evaluation of this call always throws an exception.
+   * Holds if the evaluation of this call always throws an exception of the kind represented by the `ExceptionEdge`.
    */
-  abstract predicate mustThrowException();
+  abstract predicate mustThrowException(ExceptionEdge e);
 
   /**
    * Gets the result type of the call.
@@ -332,14 +331,14 @@ class TranslatedExprCall extends TranslatedCallExpr {
     result = getTranslatedExpr(expr.getExpr().getFullyConverted())
   }
 
-  final override predicate mayThrowException() {
+  final override predicate mayThrowException(ExceptionEdge e) {
     // We assume that a call to a function pointer will not throw an exception.
     // This is not sound in general, but this will greatly reduce the number of
     // exceptional edges.
     none()
   }
 
-  final override predicate mustThrowException() { none() }
+  final override predicate mustThrowException(ExceptionEdge e) { none() }
 }
 
 /**
@@ -362,16 +361,16 @@ class TranslatedFunctionCall extends TranslatedCallExpr, TranslatedDirectCall {
     not exists(MemberFunction func | expr.getTarget() = func and func.isStatic())
   }
 
-  final override predicate mayThrowException() {
-    expr.getTarget().(ThrowingFunction).mayThrowException(_)
+  final override predicate mayThrowException(ExceptionEdge e) {
+    this.mustThrowException(e)
     or
-    expr.getTarget() instanceof AlwaysSehThrowingFunction
+    exists(MicrosoftTryStmt tryStmt | tryStmt.getStmt().getAChild*() = expr) and
+    e instanceof SehExceptionEdge
   }
 
-  final override predicate mustThrowException() {
-    expr.getTarget().(ThrowingFunction).mayThrowException(true)
-    or
-    expr.getTarget() instanceof AlwaysSehThrowingFunction
+  final override predicate mustThrowException(ExceptionEdge e) {
+    expr.getTarget() instanceof AlwaysSehThrowingFunction and
+    e instanceof SehExceptionEdge
   }
 }
 

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

@@ -2483,14 +2483,14 @@ class TranslatedAllocatorCall extends TTranslatedAllocatorCall, TranslatedDirect
         result = getTranslatedExpr(expr.getAllocatorCall().getArgument(index).getFullyConverted())
   }
 
-  final override predicate mayThrowException() {
+  final override predicate mayThrowException(ExceptionEdge e) {
     // We assume that a call to `new` or `new[]` will never throw. This is not
     // sound in general, but this will greatly reduce the number of exceptional
     // edges.
     none()
   }
 
-  final override predicate mustThrowException() { none() }
+  final override predicate mustThrowException(ExceptionEdge e) { none() }
 }
 
 TranslatedAllocatorCall getTranslatedAllocatorCall(NewOrNewArrayExpr newExpr) {
@@ -2556,14 +2556,14 @@ class TranslatedDeleteOrDeleteArrayExpr extends TranslatedNonConstantExpr, Trans
     result = getTranslatedExpr(expr.getExprWithReuse().getFullyConverted())
   }
 
-  final override predicate mayThrowException() {
+  final override predicate mayThrowException(ExceptionEdge e) {
     // We assume that a call to `delete` or `delete[]` will never throw. This is not
     // sound in general, but this will greatly reduce the number of exceptional
     // edges.
     none()
   }
 
-  final override predicate mustThrowException() { none() }
+  final override predicate mustThrowException(ExceptionEdge e) { none() }
 }
 
 TranslatedDeleteOrDeleteArrayExpr getTranslatedDeleteOrDeleteArray(DeleteOrDeleteArrayExpr newExpr) {

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

@@ -214,7 +214,7 @@ class TranslatedFunction extends TranslatedRootElement, TTranslatedFunction {
         exists(ThrowExpr throw | throw.getEnclosingFunction() = func)
         or
         exists(FunctionCall call | call.getEnclosingFunction() = func |
-          getTranslatedExpr(call).(TranslatedCallExpr).mayThrowException()
+          getTranslatedExpr(call).(TranslatedCallExpr).mayThrowException(_)
         )
       )
       or

cpp/ql/lib/semmle/code/cpp/models/interfaces/Throwing.qll

@@ -12,8 +12,10 @@ import semmle.code.cpp.models.interfaces.FunctionInputsAndOutputs
 
 /**
  * A function that is known to raise an exception.
+ *
+ * DEPRECATED: use `AlwaysSehThrowingFunction` instead.
  */
-abstract class ThrowingFunction extends Function {
+abstract deprecated class ThrowingFunction extends Function {
   /**
    * Holds if this function may throw an exception during evaluation.
    * If `unconditional` is `true` the function always throws an exception.