Merge pull request #1532 from zlaski-semmle/zlaski/cpp386

[CPP-386] Add `getCanonicalQLClass()` for AST QL elements.

Author: geoffw0

cpp/ql/src/semmle/code/cpp/Class.qll

@@ -15,6 +15,8 @@ class Class extends UserType {
     isClass(underlyingElement(this))
   }
 
+  override string getCanonicalQLClass() { result = "Class" }
+  
   /** Gets a child declaration of this class. */
   override Declaration getADeclaration() { result = this.getAMember() }
 
@@ -822,6 +824,9 @@ class LocalClass extends Class {
     isLocal()
   }
 
+  override string getCanonicalQLClass()
+    { not this instanceof LocalStruct and result = "LocalClass" }
+
   override Function getEnclosingAccessHolder() {
     result = this.getEnclosingFunction()
   }
@@ -835,6 +840,9 @@ class NestedClass extends Class {
     this.isMember()
   }
 
+  override string getCanonicalQLClass() 
+    { not this instanceof NestedStruct and result = "NestedClass" }
+
   /** Holds if this member is private. */
   predicate isPrivate() { this.hasSpecifier("private") }
 
@@ -854,6 +862,8 @@ class AbstractClass extends Class {
   AbstractClass() {
     exists(PureVirtualFunction f| this.getAMemberFunction() = f)
   }
+
+  override string getCanonicalQLClass() { result = "AbstractClass" }
 }
 
 /**
@@ -866,6 +876,8 @@ class TemplateClass extends Class {
     result.isConstructedFrom(this) and
     exists(result.getATemplateArgument())
   }
+
+  override string getCanonicalQLClass() { result = "TemplateClass" }
 }
 
 /**
@@ -878,6 +890,8 @@ class ClassTemplateInstantiation extends Class {
     tc.getAnInstantiation() = this
   }
 
+  override string getCanonicalQLClass() { result = "ClassTemplateInstantiation" }
+
   /**
    * Gets the class template from which this instantiation was instantiated.
    *
@@ -909,6 +923,8 @@ abstract class ClassTemplateSpecialization extends Class {
     and count(TemplateParameter tp | tp = result.getATemplateArgument()) =
         count(int i | exists(result.getTemplateArgument(i)))
   }
+
+  override string getCanonicalQLClass() { result = "ClassTemplateSpecialization" }
 }
 
 /**
@@ -926,6 +942,8 @@ class FullClassTemplateSpecialization extends ClassTemplateSpecialization {
     // This class is not an instantiation of a class template.
     and not this instanceof ClassTemplateInstantiation
   }
+
+  override string getCanonicalQLClass() { result = "FullClassTemplateSpecialization" }
 }
 
 /**
@@ -950,6 +968,8 @@ class PartialClassTemplateSpecialization extends ClassTemplateSpecialization {
     and count(TemplateParameter tp | tp = getATemplateArgument()) !=
         count(int i | exists(getTemplateArgument(i)))
   }
+
+  override string getCanonicalQLClass() { result = "PartialClassTemplateSpecialization" }
 }
 
 /**
@@ -960,6 +980,8 @@ class Interface extends Class {
   Interface() {
     forex(Declaration m | m.getDeclaringType() = this.getABaseClass*() and not compgenerated(unresolveElement(m)) | m instanceof PureVirtualFunction)
   }
+
+  override string getCanonicalQLClass() { result = "Interface" }
 }
 
 /**
@@ -970,6 +992,8 @@ class VirtualClassDerivation extends ClassDerivation {
   VirtualClassDerivation() {
     hasSpecifier("virtual")
   }
+
+  override string getCanonicalQLClass() { result = "VirtualClassDerivation" }
 }
 
 /**
@@ -980,6 +1004,8 @@ class VirtualBaseClass extends Class {
     exists(VirtualClassDerivation cd | cd.getBaseClass() = this)
   }
 
+  override string getCanonicalQLClass() { result = "VirtualBaseClass" }
+
   /** A virtual class derivation of which this class is the base. */
   VirtualClassDerivation getAVirtualDerivation() {
     result.getBaseClass() = this
@@ -1004,6 +1030,8 @@ class ProxyClass extends UserType {
     usertypes(underlyingElement(this),_,9)
   }
 
+  override string getCanonicalQLClass() { result = "ProxyClass" }
+  
   /** Gets the location of the proxy class. */
   override Location getLocation() {
     result = getTemplateParameter().getDefinitionLocation()

cpp/ql/src/semmle/code/cpp/Element.qll

@@ -52,6 +52,13 @@ pragma[inline]
 class ElementBase extends @element {
   /** Gets a textual representation of this element. */
   string toString() { none() }
+
+  /** 
+   * Canonical QL class corresponding to this element.
+   *  
+   * ElementBase is the root class for this predicate.
+   */
+  string getCanonicalQLClass() { result = "???" }
 }
 
 /**

cpp/ql/src/semmle/code/cpp/Enum.qll

@@ -9,6 +9,8 @@ class Enum extends UserType, IntegralOrEnumType {
   EnumConstant getAnEnumConstant() { result.getDeclaringEnum() = this }
   EnumConstant getEnumConstant(int index) { enumconstants(unresolveElement(result),underlyingElement(this),index,_,_,_) }
 
+  override string getCanonicalQLClass() { result = "Enum" }
+
   /**
    * Gets a descriptive string for the enum. This method is only intended to
    * be used for debugging purposes. For more information, see the comment
@@ -50,6 +52,8 @@ class LocalEnum extends Enum {
   LocalEnum() {
     isLocal()
   }
+
+  override string getCanonicalQLClass() { result = "LocalEnum" }
 }
 
 /**
@@ -61,6 +65,8 @@ class NestedEnum extends Enum {
     this.isMember()
   }
 
+  override string getCanonicalQLClass() { result = "NestedEnum" }
+  
   /** Holds if this member is private. */
   predicate isPrivate() { this.hasSpecifier("private") }
 
@@ -81,6 +87,8 @@ class ScopedEnum extends Enum {
   ScopedEnum() {
     usertypes(underlyingElement(this),_,13)
   }
+
+  override string getCanonicalQLClass() { result = "ScopedEnum" }
 }
 
 /**
@@ -96,6 +104,8 @@ class EnumConstant extends Declaration, @enumconstant {
    */
   Enum getDeclaringEnum() { enumconstants(underlyingElement(this),unresolveElement(result),_,_,_,_) }
 
+  override string getCanonicalQLClass() { result = "EnumConstant" }
+  
   override Class getDeclaringType() {
     result = this.getDeclaringEnum().getDeclaringType()
   }

cpp/ql/src/semmle/code/cpp/Function.qll

@@ -503,6 +503,8 @@ class FunctionDeclarationEntry extends DeclarationEntry, @fun_decl {
   /** Gets the function which is being declared or defined. */
   override Function getDeclaration() { result = getFunction() }
 
+  override string getCanonicalQLClass() { result = "FunctionDeclarationEntry" }
+
   /** Gets the function which is being declared or defined. */
   Function getFunction() { fun_decls(underlyingElement(this),unresolveElement(result),_,_,_) }
 
@@ -707,6 +709,8 @@ class TopLevelFunction extends Function {
   TopLevelFunction() {
     not this.isMember()
   }
+
+  override string getCanonicalQLClass() { result = "TopLevelFunction" }
 }
 
 /**
@@ -718,6 +722,11 @@ class MemberFunction extends Function {
     this.isMember()
   }
 
+  override string getCanonicalQLClass() 
+    { not this instanceof CopyAssignmentOperator and 
+      not this instanceof MoveAssignmentOperator and 
+      result = "MemberFunction" }
+
   /**
    * Gets the number of parameters of this function, including any implicit
    * `this` parameter.
@@ -769,6 +778,8 @@ class VirtualFunction extends MemberFunction {
     this.hasSpecifier("virtual") or purefunctions(underlyingElement(this))
   }
 
+  override string getCanonicalQLClass() { result = "VirtualFunction" }
+  
   /** Holds if this virtual function is pure. */
   predicate isPure() { this instanceof PureVirtualFunction }
 
@@ -786,6 +797,7 @@ class PureVirtualFunction extends VirtualFunction {
 
   PureVirtualFunction() { purefunctions(underlyingElement(this)) }
 
+  override string getCanonicalQLClass() { result = "PureVirtualFunction" }
 }
 
 /**
@@ -797,6 +809,7 @@ class ConstMemberFunction extends MemberFunction {
 
   ConstMemberFunction() { this.hasSpecifier("const") }
 
+  override string getCanonicalQLClass() { result = "ConstMemberFunction" }
 }
 
 /**
@@ -806,6 +819,8 @@ class Constructor extends MemberFunction {
 
   Constructor() { functions(underlyingElement(this),_,2) }
 
+  override string getCanonicalQLClass() { result = "Constructor" }
+  
   /**
    * Holds if this constructor serves as a default constructor.
    *
@@ -851,6 +866,9 @@ class ConversionConstructor extends Constructor, ImplicitConversionFunction {
     and not(this instanceof CopyConstructor)
   }
 
+  override string getCanonicalQLClass() 
+    { not this instanceof MoveConstructor and result = "ConversionConstructor" }
+  
   /** Gets the type this `ConversionConstructor` takes as input. */
   override Type getSourceType() { result = this.getParameter(0).getType() }
 
@@ -906,6 +924,8 @@ class CopyConstructor extends Constructor {
     not exists(getATemplateArgument())
   }
 
+  override string getCanonicalQLClass() { result = "CopyConstructor" }
+  
   /**
    * Holds if we cannot determine that this constructor will become a copy
    * constructor in all instantiations. Depending on template parameters of the
@@ -954,6 +974,8 @@ class MoveConstructor extends Constructor {
     not exists(getATemplateArgument())
   }
 
+  override string getCanonicalQLClass() { result = "MoveConstructor" }
+  
   /**
    * Holds if we cannot determine that this constructor will become a move
    * constructor in all instantiations. Depending on template parameters of the
@@ -986,6 +1008,8 @@ class NoArgConstructor extends Constructor {
 class Destructor extends MemberFunction {
   Destructor() { functions(underlyingElement(this),_,3) }
 
+  override string getCanonicalQLClass() { result = "Destructor" }
+  
   /**
    * Gets a compiler-generated action which destructs a base class or member
    * variable.
@@ -1011,6 +1035,8 @@ class ConversionOperator extends MemberFunction, ImplicitConversionFunction {
 
   ConversionOperator() { functions(underlyingElement(this),_,4) }
 
+  override string getCanonicalQLClass() { result = "ConversionOperator" }
+
   override Type getSourceType() { result = this.getDeclaringType() }
   override Type getDestType() { result = this.getType() }
 
@@ -1023,6 +1049,8 @@ class Operator extends Function {
 
   Operator() { functions(underlyingElement(this),_,5) }
 
+  override string getCanonicalQLClass() 
+    { not this instanceof MemberFunction and result = "Operator" }
 }
 
 /**
@@ -1045,6 +1073,8 @@ class CopyAssignmentOperator extends Operator {
     not exists(this.getParameter(1)) and
     not exists(getATemplateArgument())
   }
+
+  override string getCanonicalQLClass() { result = "CopyAssignmentOperator" }
 }
 
 
@@ -1064,6 +1094,8 @@ class MoveAssignmentOperator extends Operator {
     not exists(this.getParameter(1)) and
     not exists(getATemplateArgument())
   }
+
+  override string getCanonicalQLClass() { result = "MoveAssignmentOperator" }
 }
 
 
@@ -1084,6 +1116,7 @@ class MoveAssignmentOperator extends Operator {
 class TemplateFunction extends Function {
   TemplateFunction() { is_function_template(underlyingElement(this)) and exists(getATemplateArgument()) }
 
+  override string getCanonicalQLClass() { result = "TemplateFunction" }
   /**
    * Gets a compiler-generated instantiation of this function template.
    */
@@ -1115,6 +1148,8 @@ class FunctionTemplateInstantiation extends Function {
     tf.getAnInstantiation() = this
   }
 
+  override string getCanonicalQLClass() { result = "FunctionTemplateInstantiation" }
+
   /**
    * Gets the function template from which this instantiation was instantiated.
    *
@@ -1151,6 +1186,8 @@ class FunctionTemplateSpecialization extends Function {
     this.isSpecialization()
   }
 
+  override string getCanonicalQLClass() { result = "FunctionTemplateSpecialization" }
+  
   /**
    * Gets the primary template for the specialization (the function template
    * this specializes).

cpp/ql/src/semmle/code/cpp/Initializer.qll

@@ -6,6 +6,8 @@ import semmle.code.cpp.controlflow.ControlFlowGraph
 class Initializer extends ControlFlowNode, @initialiser {
   override Location getLocation() { initialisers(underlyingElement(this),_,_,result) }
 
+  override string getCanonicalQLClass() { result = "Initializer" }
+  
   /** Holds if this initializer is explicit in the source. */
   override predicate fromSource() {
     not (this.getLocation() instanceof UnknownLocation)

cpp/ql/src/semmle/code/cpp/Macro.qll

@@ -11,6 +11,8 @@ class Macro extends PreprocessorDirective, @ppd_define {
    */
   override string getHead() { preproctext(underlyingElement(this),result,_) }
 
+  override string getCanonicalQLClass() { result = "Macro" }
+
   /**
    * Gets the body of this macro. For example, `(((x)>(y))?(x):(y))` in
    * `#define MAX(x,y) (((x)>(y))?(x):(y))`.

cpp/ql/src/semmle/code/cpp/Parameter.qll

@@ -33,6 +33,8 @@ class Parameter extends LocalScopeVariable, @parameter {
      result = "p#" + this.getIndex().toString())
   }
 
+  override string getCanonicalQLClass() { result = "Parameter" }
+
   /**
    * Gets the name of this parameter, including it's type.
    *