C++: upgrade script for member_function_this_type

cpp/upgrades/282c13bfdbcbd57a887972b47a471342a4ad5507/member_function_this_type.ql

@@ -0,0 +1,48 @@
+/*
+ * Upgrade script to populate the member_function_this_type table. It's a rough
+ * approximation of what the extractor would do - for a member function C::f,
+ * we say its type is C* (if that pointer type exists in the database).
+ * CV-qualifiers are ignored.
+ */
+
+class Class extends @usertype {
+  Class() {
+    usertypes(this, _, 1) or
+    usertypes(this, _, 2) or
+    usertypes(this, _, 3) or
+    usertypes(this, _, 6) or
+    usertypes(this, _, 10) or
+    usertypes(this, _, 11) or
+    usertypes(this, _, 12)
+  }
+
+  string toString() { usertypes(this, result, _) }
+}
+
+class ClassPointerType extends @derivedtype {
+  ClassPointerType() { derivedtypes(this, _, 1, _) }
+
+  Class getBaseType() { derivedtypes(this, _, _, result) }
+
+  string toString() { result = getBaseType().toString() + "*" }
+}
+
+class DefinedMemberFunction extends @function {
+  DefinedMemberFunction() {
+    exists(@fun_decl fd |
+      fun_def(fd) and
+      (
+        fun_decls(fd, this, _, _, _)
+        or
+        exists(@function f | function_instantiation(this, f) and fun_decls(fd, f, _, _, _))
+      )
+    )
+  }
+
+  ClassPointerType getTypeOfThis() { member(result.getBaseType(), _, this) }
+
+  string toString() { functions(this, result, _) }
+}
+
+from DefinedMemberFunction f
+select f, f.getTypeOfThis()

cpp/upgrades/282c13bfdbcbd57a887972b47a471342a4ad5507/upgrade.properties

@@ -0,0 +1,3 @@
+description: Add table relating a member function to the type of `this`.
+compatibility: partial
+member_function_this_type.rel: run member_function_this_type.qlo