C++: Handle field initialization via NSDMI in IR generation

cpp/ql/lib/semmle/code/cpp/exprs/Call.qll

@@ -585,12 +585,15 @@ class ConstructorDelegationInit extends ConstructorBaseInit, @ctordelegatinginit
 
 /**
  * An initialization of a member variable performed as part of a
- * constructor's explicit initializer list or implicit actions.
+ * constructor's initializer list or by default initialization.
+ *
  * In the example below, member variable `b` is being initialized by
- * constructor parameter `a`:
+ * constructor parameter `a`, and `c` is initialized by default
+ * initialization:
  * ```
  * struct S {
  *   int b;
+ *   int c = 3;
  *   S(int a): b(a) {}
  * } s(2);
  * ```
@@ -616,6 +619,28 @@ class ConstructorFieldInit extends ConstructorInit, @ctorfieldinit {
   override predicate mayBeGloballyImpure() { this.getExpr().mayBeGloballyImpure() }
 }
 
+/**
+ * An initialization of a member variable performed as part of a
+ * constructor's explicit initializer list.
+ */
+class ConstructorDirectFieldInit extends ConstructorFieldInit {
+  ConstructorDirectFieldInit() { exists(this.getChild(0)) }
+
+  override string getAPrimaryQlClass() { result = "ConstructorDirectFieldInit" }
+}
+
+/**
+ * An initialization of a member variable performed by default
+ * initialization.
+ */
+class ConstructorDefaultFieldInit extends ConstructorFieldInit {
+  ConstructorDefaultFieldInit() {
+    not exists(this.getChild(0)) and exists(this.getTarget().getInitializer())
+  }
+
+  override string getAPrimaryQlClass() { result = "ConstructorDefaultFieldInit" }
+}
+
 /**
  * A call to a destructor of a base class or field as part of a destructor's
  * compiler-generated actions.

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

@@ -15,6 +15,7 @@ private import TranslatedCall
 private import TranslatedStmt
 private import TranslatedFunction
 private import TranslatedGlobalVar
+private import TranslatedNonStaticDataMember
 private import TranslatedInitialization
 
 TranslatedElement getInstructionTranslatedElement(Instruction instruction) {
@@ -45,6 +46,8 @@ module Raw {
       or
       not var.isFromUninstantiatedTemplate(_) and
       var instanceof StaticInitializedStaticLocalVariable
+      or
+      var instanceof Field
     ) and
     var.hasInitializer() and
     (
@@ -64,6 +67,8 @@ module Raw {
     getTranslatedFunction(decl).hasUserVariable(var, type)
     or
     getTranslatedVarInit(decl).hasUserVariable(var, type)
+    or
+    getTranslatedFieldInit(decl).hasUserVariable(var, type)
   }
 
   cached

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

@@ -130,13 +130,13 @@ private predicate hasDefaultSideEffect(Call call, ParameterIndex i, boolean buff
 }
 
 /**
- * A `Call` or `NewOrNewArrayExpr` or `DeleteOrDeleteArrayExpr`.
+ * An expression that can have call side effects.
  *
- * All kinds of expression invoke a function as part of their evaluation. This class provides a
- * way to treat both kinds of function similarly, and to get the invoked `Function`.
+ * All kinds of expressions invoke a function as part of their evaluation. This class provides a
+ * way to treat those functions similarly, and to get the invoked `Function`.
  */
-class CallOrAllocationExpr extends Expr {
-  CallOrAllocationExpr() {
+class ExprWithCallSizeEffects extends Expr {
+  ExprWithCallSizeEffects() {
     this instanceof Call
     or
     this instanceof NewOrNewArrayExpr
@@ -158,7 +158,7 @@ class CallOrAllocationExpr extends Expr {
  * Returns the side effect opcode, if any, that represents any side effects not specifically modeled
  * by an argument side effect.
  */
-Opcode getCallSideEffectOpcode(CallOrAllocationExpr expr) {
+Opcode getCallSideEffectOpcode(ExprWithCallSizeEffects expr) {
   not exists(expr.getTarget().(SideEffectFunction)) and result instanceof Opcode::CallSideEffect
   or
   exists(SideEffectFunction sideEffectFunction |

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

@@ -36,7 +36,8 @@ abstract class TranslatedCondition extends TranslatedElement {
   final override Declaration getFunction() {
     result = getEnclosingFunction(expr) or
     result = getEnclosingVariable(expr).(GlobalOrNamespaceVariable) or
-    result = getEnclosingVariable(expr).(StaticInitializedStaticLocalVariable)
+    result = getEnclosingVariable(expr).(StaticInitializedStaticLocalVariable) or
+    result = getEnclosingVariable(expr).(Field)
   }
 
   final Type getResultType() { result = expr.getUnspecifiedType() }

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

@@ -36,6 +36,7 @@ abstract class TranslatedDeclarationEntry extends TranslatedElement, TTranslated
       or
       not entry.getDeclaration() instanceof StaticInitializedStaticLocalVariable and
       not entry.getDeclaration() instanceof GlobalOrNamespaceVariable and
+      not entry.getDeclaration() instanceof Field and
       result = stmt.getEnclosingFunction()
     )
   }

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

@@ -871,7 +871,7 @@ newtype TTranslatedElement =
   // The declaration/initialization part of a `ConditionDeclExpr`
   TTranslatedConditionDecl(ConditionDeclExpr expr) { not ignoreExpr(expr) } or
   // The side effects of a `Call`
-  TTranslatedCallSideEffects(CallOrAllocationExpr expr) {
+  TTranslatedCallSideEffects(ExprWithCallSizeEffects expr) {
     not ignoreExpr(expr) and
     not ignoreSideEffects(expr)
   } or
@@ -918,7 +918,10 @@ newtype TTranslatedElement =
   } or
   // The side effect that initializes newly-allocated memory.
   TTranslatedAllocationSideEffect(AllocationExpr expr) { not ignoreSideEffects(expr) } or
-  TTranslatedStaticStorageDurationVarInit(Variable var) { Raw::varHasIRFunc(var) } or
+  TTranslatedStaticStorageDurationVarInit(Variable var) {
+    Raw::varHasIRFunc(var) and not var instanceof Field
+  } or
+  TTranslatedNonStaticDataMemberVarInit(Field var) { Raw::varHasIRFunc(var) } or
   TTranslatedAssertionOperand(MacroInvocation mi, int index) { hasAssertionOperand(mi, index) }
 
 /**
@@ -1297,5 +1300,7 @@ abstract class TranslatedRootElement extends TranslatedElement {
     this instanceof TTranslatedFunction
     or
     this instanceof TTranslatedStaticStorageDurationVarInit
+    or
+    this instanceof TTranslatedNonStaticDataMemberVarInit
   }
 }

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

@@ -14,6 +14,7 @@ private import TranslatedFunction
 private import TranslatedInitialization
 private import TranslatedStmt
 private import TranslatedGlobalVar
+private import TranslatedNonStaticDataMember
 private import IRConstruction
 import TranslatedCall
 
@@ -138,6 +139,8 @@ abstract class TranslatedExpr extends TranslatedElement {
     result = getTranslatedFunction(getEnclosingFunction(expr))
     or
     result = getTranslatedVarInit(getEnclosingVariable(expr))
+    or
+    result = getTranslatedFieldInit(getEnclosingVariable(expr))
   }
 }
 
@@ -153,7 +156,10 @@ Declaration getEnclosingDeclaration0(Expr e) {
     i.getExpr().getFullyConverted() = e and
     v = i.getDeclaration()
   |
-    if v instanceof StaticInitializedStaticLocalVariable or v instanceof GlobalOrNamespaceVariable
+    if
+      v instanceof StaticInitializedStaticLocalVariable or
+      v instanceof GlobalOrNamespaceVariable or
+      v instanceof Field
     then result = v
     else result = e.getEnclosingDeclaration()
   )
@@ -173,7 +179,10 @@ Variable getEnclosingVariable0(Expr e) {
     i.getExpr().getFullyConverted() = e and
     v = i.getDeclaration()
   |
-    if v instanceof StaticInitializedStaticLocalVariable or v instanceof GlobalOrNamespaceVariable
+    if
+      v instanceof StaticInitializedStaticLocalVariable or
+      v instanceof GlobalOrNamespaceVariable or
+      v instanceof Field
     then result = v
     else result = e.getEnclosingVariable()
   )
@@ -826,6 +835,46 @@ class TranslatedPostfixCrementOperation extends TranslatedCrementOperation {
   override Instruction getResult() { result = this.getLoadedOperand().getResult() }
 }
 
+class TranslatedParamAccessForType extends TranslatedNonConstantExpr {
+  override ParamAccessForType expr;
+
+  TranslatedParamAccessForType() {
+    // Currently only needed for this parameter accesses.
+    expr.isThisAccess()
+  }
+
+  final override Instruction getFirstInstruction(EdgeKind kind) {
+    result = this.getInstruction(OnlyInstructionTag()) and
+    kind instanceof GotoEdge
+  }
+
+  override Instruction getALastInstructionInternal() {
+    result = this.getInstruction(OnlyInstructionTag())
+  }
+
+  final override TranslatedElement getChildInternal(int id) { none() }
+
+  override Instruction getInstructionSuccessorInternal(InstructionTag tag, EdgeKind kind) {
+    tag = OnlyInstructionTag() and
+    result = this.getParent().getChildSuccessor(this, kind)
+  }
+
+  override Instruction getResult() { result = this.getInstruction(OnlyInstructionTag()) }
+
+  override predicate hasInstruction(Opcode opcode, InstructionTag tag, CppType resultType) {
+    tag = OnlyInstructionTag() and
+    opcode instanceof Opcode::CopyValue and
+    resultType = getTypeForPRValue(expr.getType())
+  }
+
+  override Instruction getInstructionRegisterOperand(InstructionTag tag, OperandTag operandTag) {
+    tag = OnlyInstructionTag() and
+    operandTag instanceof UnaryOperandTag and
+    result =
+      this.getEnclosingFunction().(TranslatedNonStaticDataMemberVarInit).getLoadThisInstruction()
+  }
+}
+
 /**
  * IR translation of an array access expression (e.g. `a[i]`). The array being accessed will either
  * be a prvalue of pointer type (possibly due to an implicit array-to-pointer conversion), or a

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

@@ -148,7 +148,8 @@ abstract class TranslatedInitialization extends TranslatedElement, TTranslatedIn
   final override Declaration getFunction() {
     result = getEnclosingFunction(expr) or
     result = getEnclosingVariable(expr).(GlobalOrNamespaceVariable) or
-    result = getEnclosingVariable(expr).(StaticInitializedStaticLocalVariable)
+    result = getEnclosingVariable(expr).(StaticInitializedStaticLocalVariable) or
+    result = getEnclosingVariable(expr).(Field)
   }
 
   final override Locatable getAst() { result = expr }
@@ -528,7 +529,8 @@ abstract class TranslatedFieldInitialization extends TranslatedElement {
   final override Declaration getFunction() {
     result = getEnclosingFunction(ast) or
     result = getEnclosingVariable(ast).(GlobalOrNamespaceVariable) or
-    result = getEnclosingVariable(ast).(StaticInitializedStaticLocalVariable)
+    result = getEnclosingVariable(ast).(StaticInitializedStaticLocalVariable) or
+    result = getEnclosingVariable(ast).(Field)
   }
 
   final override Instruction getFirstInstruction(EdgeKind kind) {
@@ -701,6 +703,8 @@ abstract class TranslatedElementInitialization extends TranslatedElement {
     result = getEnclosingVariable(initList).(GlobalOrNamespaceVariable)
     or
     result = getEnclosingVariable(initList).(StaticInitializedStaticLocalVariable)
+    or
+    result = getEnclosingVariable(initList).(Field)
   }
 
   final override Instruction getFirstInstruction(EdgeKind kind) {