Python: add new shared-SSA-backed SSA adapter

Preparatory refactor for the shared-CFG dataflow migration. Adds the
new Python SSA adapter additively, without changing any production
behaviour.

Library additions:

- semmle.python.dataflow.new.internal.SsaImpl — Python SSA
  implementation built on the new (shared) CFG. Mirrors the Java SSA
  adapter (java/ql/lib/semmle/code/java/dataflow/internal/SsaImpl.qll):
  an InputSig is defined in terms of positional (BasicBlock, int)
  variable references, and the shared
  codeql.ssa.Ssa::Make<Location, Cfg, Input> module is then
  instantiated.

  SourceVariable is the AST-level Py::Variable. Variable references
  are looked up via the new CFG facade's NameNode.defines/uses/deletes
  predicates (added in the preceding PR), which themselves are
  one-line bridges to AST-level Name.defines/uses/deletes.

  Implicit-entry definitions are inserted for non-local/global/builtin
  reads, captured variables, and (when needed) parameters.

Test additions:

- library-tests/dataflow-new-ssa/ — exercises the new SSA over a
  representative test corpus and checks expected def/use chains.

- library-tests/dataflow-new-ssa-vs-legacy/ — runs both new SSA and
  legacy ESSA over the same corpus and diffs the results, so any
  semantic divergence shows up as a test failure.

Production impact:

None. The new SSA adapter has zero callers in lib/ and src/ — the
legacy ESSA SSA (semmle/python/essa/*) remains the default. The
dataflow library is not migrated yet; that lands in a follow-up PR.

Verified by:
- All 367 lib + src + consistency-queries compile clean.
- All 641 ControlFlow + PointsTo + dataflow + essa + consistency
  library-tests pass.
- Both new dataflow-new-ssa[/vs-legacy] test packs pass.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

csharp/ql/lib/semmle/code/csharp/ExprOrStmtParent.qll

@@ -121,13 +121,6 @@ private module Cached {
     result = getAChildExpr(parent)
     or
     result = parent.getAChildStmt()
-    or
-    result =
-      any(TypeMention tm |
-        tm.getTarget() = parent
-        or
-        tm.getParent+().getTarget() = parent
-      )
   }
 
   private predicate parent(ControlFlowElement child, ExprOrStmtParent parent) {

csharp/ql/lib/semmle/code/csharp/Type.qll

@@ -6,7 +6,6 @@ import Generics
 import Location
 import Namespace
 import Property
-import semmle.code.csharp.controlflow.ControlFlowElement
 private import Conversion
 private import semmle.code.csharp.metrics.Coupling
 private import TypeRef
@@ -1287,7 +1286,7 @@ class TupleType extends ValueType, @tuple_type {
  * A type mention, that is, any mention of a type in a source code file.
  * For example, `int` is mentioned in `int M() { return 1; }`.
  */
-class TypeMention extends ControlFlowElement, @type_mention {
+class TypeMention extends @type_mention {
   Type type;
   @type_mention_parent parent;
 
@@ -1320,13 +1319,13 @@ class TypeMention extends ControlFlowElement, @type_mention {
    * }
    * ```
    */
-  override TypeMention getParent() { result = parent }
+  TypeMention getParent() { result = parent }
 
   /** Gets a textual representation of this type mention. */
-  override string toString() { result = type.toString() }
+  string toString() { result = type.toString() }
 
   /** Gets the location of this type mention. */
-  override Location getALocation() { type_mention_location(this, result) }
+  Location getLocation() { type_mention_location(this, result) }
 }
 
 /**

csharp/ql/lib/semmle/code/csharp/controlflow/ControlFlowElement.qll

@@ -20,7 +20,7 @@ class ControlFlowElementOrCallable extends ExprOrStmtParent, TControlFlowElement
  */
 class ControlFlowElement extends ControlFlowElementOrCallable, @control_flow_element {
   /** Gets the enclosing callable of this element, if any. */
-  Callable getEnclosingCallable() { enclosingCallable(this, result) }
+  Callable getEnclosingCallable() { none() }
 
   /** Gets the assembly that this element was compiled into. */
   Assembly getAssembly() {

csharp/ql/lib/semmlecode.csharp.dbscheme

@@ -219,7 +219,7 @@ overlayChangedFiles(
 /** ELEMENTS **/
 
 @element = @declaration | @stmt | @expr | @modifier | @attribute | @namespace_declaration
-         | @using_directive | @type_parameter_constraints | @type_mention | @externalDataElement
+         | @using_directive | @type_parameter_constraints | @externalDataElement
          | @xmllocatable | @asp_element | @namespace | @preprocessor_directive;
 
 @declaration = @callable | @generic | @assignable | @namespace;
@@ -1369,7 +1369,7 @@ compiler_generated(unique int id: @element ref);
 
 /** CONTROL/DATA FLOW **/
 
-@control_flow_element = @stmt | @expr | @parameter | @type_mention;
+@control_flow_element = @stmt | @expr | @parameter;
 
 /* XML Files */
 

python/ql/consistency-queries/CfgConsistency.ql

@@ -0,0 +1,2 @@
+import semmle.python.controlflow.internal.AstNodeImpl
+import ControlFlow::Consistency

python/ql/lib/LegacyPointsTo.qll

@@ -213,9 +213,11 @@ class ExprWithPointsTo extends Expr {
    * Gets what this expression might "refer-to" in the given `context`.
    */
   predicate refersTo(Context context, Object obj, ClassObject cls, AstNode origin) {
-    this.getAFlowNode()
+    exists(ControlFlowNode this_, ControlFlowNode origin_ |
-        .(ControlFlowNodeWithPointsTo)
+      this_.getNode() = this and origin_.getNode() = origin
-        .refersTo(context, obj, cls, origin.getAFlowNode())
+    |
+      this_.(ControlFlowNodeWithPointsTo).refersTo(context, obj, cls, origin_)
+    )
   }
 
   /**
@@ -226,7 +228,11 @@ class ExprWithPointsTo extends Expr {
    */
   pragma[nomagic]
   predicate refersTo(Object obj, AstNode origin) {
-    this.getAFlowNode().(ControlFlowNodeWithPointsTo).refersTo(obj, origin.getAFlowNode())
+    exists(ControlFlowNode this_, ControlFlowNode origin_ |
+      this_.getNode() = this and origin_.getNode() = origin
+    |
+      this_.(ControlFlowNodeWithPointsTo).refersTo(obj, origin_)
+    )
   }
 
   /**
@@ -240,16 +246,22 @@ class ExprWithPointsTo extends Expr {
    * in the given `context`.
    */
   predicate pointsTo(Context context, Value value, AstNode origin) {
-    this.getAFlowNode()
+    exists(ControlFlowNode this_, ControlFlowNode origin_ |
-        .(ControlFlowNodeWithPointsTo)
+      this_.getNode() = this and origin_.getNode() = origin
-        .pointsTo(context, value, origin.getAFlowNode())
+    |
+      this_.(ControlFlowNodeWithPointsTo).pointsTo(context, value, origin_)
+    )
   }
 
   /**
    * Holds if this expression might "point-to" to `value` which is from `origin`.
    */
   predicate pointsTo(Value value, AstNode origin) {
-    this.getAFlowNode().(ControlFlowNodeWithPointsTo).pointsTo(value, origin.getAFlowNode())
+    exists(ControlFlowNode this_, ControlFlowNode origin_ |
+      this_.getNode() = this and origin_.getNode() = origin
+    |
+      this_.(ControlFlowNodeWithPointsTo).pointsTo(value, origin_)
+    )
   }
 
   /**
@@ -475,7 +487,10 @@ class FunctionMetricsWithPointsTo extends FunctionMetrics {
     not non_coupling_method(result) and
     exists(Call call | call.getScope() = this |
       exists(FunctionObject callee | callee.getFunction() = result |
-        call.getAFlowNode().getFunction().(ControlFlowNodeWithPointsTo).refersTo(callee)
+        exists(CallNode call_ |
+          call_.getNode() = call and
+          call_.getFunction().(ControlFlowNodeWithPointsTo).refersTo(callee)
+        )
       )
       or
       exists(Attribute a | call.getFunc() = a |

python/ql/lib/analysis/DefinitionTracking.qll

@@ -64,7 +64,7 @@ private predicate jump_to_defn(ControlFlowNode use, Definition defn) {
 private predicate preferred_jump_to_defn(Expr use, Definition def) {
   not use instanceof ClassExpr and
   not use instanceof FunctionExpr and
-  jump_to_defn(use.getAFlowNode(), def)
+  exists(ControlFlowNode useNode | useNode.getNode() = use | jump_to_defn(useNode, def))
 }
 
 private predicate unique_jump_to_defn(Expr use, Definition def) {
@@ -452,7 +452,7 @@ private predicate self_parameter_jump_to_defn_attribute(
  * This exists primarily for testing use `getPreferredDefinition()` instead.
  */
 Definition getADefinition(Expr use) {
-  jump_to_defn(use.getAFlowNode(), result) and
+  exists(ControlFlowNode useNode | useNode.getNode() = use | jump_to_defn(useNode, result)) and
   not use instanceof Call and
   not use.isArtificial() and
   // Not the use itself

python/ql/lib/change-notes/2026-05-19-add-shared-cfg.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* A new Python control flow graph implementation has been added under `semmle.python.controlflow.internal.Cfg` (backed by `AstNodeImpl.qll`), built on the shared `codeql.controlflow.ControlFlowGraph` library. It is not yet used by the dataflow library or any production query; the legacy CFG in `semmle/python/Flow.qll` remains the default. The new library is exposed for tests and for upcoming migrations.

python/ql/lib/change-notes/2026-05-19-add-shared-ssa.md

@@ -0,0 +1,4 @@
+---
+category: minorAnalysis
+---
+* A new SSA adapter has been added under `semmle.python.dataflow.new.internal.SsaImpl`, built on the shared `codeql.ssa.Ssa` library and the new shared CFG (`semmle.python.controlflow.internal.Cfg`). It is not yet used by the dataflow library or any production query; the legacy ESSA SSA in `semmle/python/essa/*` remains the default. The new SSA adapter is exposed for tests and for the upcoming dataflow migration.

python/ql/lib/change-notes/2026-05-19-deprecate-getAFlowNode.md

@@ -0,0 +1,5 @@
+---
+category: deprecated
+---
+* The `AstNode.getAFlowNode()` predicate has been deprecated. Use `ControlFlowNode.getNode()` from the other direction instead: replace `e.getAFlowNode() = n` with `n.getNode() = e`. This is a preparatory step towards migrating the dataflow library off the legacy CFG; it has no semantic effect.
+

python/ql/lib/change-notes/2026-06-01-deprecate-getAReturnValueFlowNode.md

@@ -0,0 +1,4 @@
+---
+category: deprecated
+---
+* The `Function.getAReturnValueFlowNode()` predicate has been deprecated. Bind a `Return` node explicitly instead — `exists(Return ret | ret.getScope() = f and n.getNode() = ret.getValue())`. This is a preparatory step towards migrating the dataflow library off the legacy CFG; it has no semantic effect.

python/ql/lib/printCfgNew.ql

@@ -0,0 +1,45 @@
+/**
+ * @name Print CFG (New)
+ * @description Produces a representation of a file's Control Flow Graph
+ *              using the new shared control flow library.
+ *              This query is used by the VS Code extension.
+ * @id python/print-cfg
+ * @kind graph
+ * @tags ide-contextual-queries/print-cfg
+ */
+
+private import python as Py
+import semmle.python.controlflow.internal.AstNodeImpl
+
+external string selectedSourceFile();
+
+private predicate selectedSourceFileAlias = selectedSourceFile/0;
+
+external int selectedSourceLine();
+
+private predicate selectedSourceLineAlias = selectedSourceLine/0;
+
+external int selectedSourceColumn();
+
+private predicate selectedSourceColumnAlias = selectedSourceColumn/0;
+
+module ViewCfgQueryInput implements ControlFlow::ViewCfgQueryInputSig<Py::File> {
+  predicate selectedSourceFile = selectedSourceFileAlias/0;
+
+  predicate selectedSourceLine = selectedSourceLineAlias/0;
+
+  predicate selectedSourceColumn = selectedSourceColumnAlias/0;
+
+  predicate cfgScopeSpan(
+    Ast::Callable callable, Py::File file, int startLine, int startColumn, int endLine,
+    int endColumn
+  ) {
+    exists(Py::Scope scope |
+      scope = callable.asScope() and
+      file = scope.getLocation().getFile() and
+      scope.getLocation().hasLocationInfo(_, startLine, startColumn, endLine, endColumn)
+    )
+  }
+}
+
+import ControlFlow::ViewCfgQuery<Py::File, ViewCfgQueryInput>

python/ql/lib/semmle/python/AstExtended.qll

@@ -17,12 +17,17 @@ abstract class AstNode extends AstNode_ {
   abstract Scope getScope();
 
   /**
+   * DEPRECATED: use `ControlFlowNode.getNode()` from the other direction instead;
+   * that is, replace `e.getAFlowNode() = n` with `n.getNode() = e`. This API is
+   * being removed to untangle the AST and CFG hierarchies in preparation for
+   * migrating the dataflow library off the legacy CFG.
+   *
    * Gets a flow node corresponding directly to this node.
    * NOTE: For some statements and other purely syntactic elements,
-   * there may not be a `ControlFlowNode`
+   * there may not be a `ControlFlowNode`.
    */
   cached
-  ControlFlowNode getAFlowNode() {
+  deprecated ControlFlowNode getAFlowNode() {
     Stages::AST::ref() and
     py_flow_bb_node(result, this, _, _)
   }

python/ql/lib/semmle/python/Exprs.qll

@@ -28,7 +28,9 @@ class Expr extends Expr_, AstNode {
   /** Whether this expression may have a side effect (as determined purely from its syntax) */
   predicate hasSideEffects() {
     /* If an exception raised by this expression handled, count that as a side effect */
-    this.getAFlowNode().getASuccessor().getNode() instanceof ExceptStmt
+    exists(ControlFlowNode n | n.getNode() = this |
+      n.getASuccessor().getNode() instanceof ExceptStmt
+    )
     or
     this.getASubExpression().hasSideEffects()
   }
@@ -68,7 +70,7 @@ class Attribute extends Attribute_ {
   /* syntax: Expr.name */
   override Expr getASubExpression() { result = this.getObject() }
 
-  override AttrNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override AttrNode getAFlowNode() { result = super.getAFlowNode() }
 
   /** Gets the name of this attribute. That is the `name` in `obj.name` */
   string getName() { result = Attribute_.super.getAttr() }
@@ -97,7 +99,7 @@ class Subscript extends Subscript_ {
 
   Expr getObject() { result = Subscript_.super.getValue() }
 
-  override SubscriptNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override SubscriptNode getAFlowNode() { result = super.getAFlowNode() }
 }
 
 /** A call expression, such as `func(...)` */
@@ -113,7 +115,7 @@ class Call extends Call_ {
 
   override string toString() { result = this.getFunc().toString() + "()" }
 
-  override CallNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override CallNode getAFlowNode() { result = super.getAFlowNode() }
 
   /** Gets a tuple (*) argument of this call. */
   Expr getStarargs() { result = this.getAPositionalArg().(Starred).getValue() }
@@ -201,7 +203,7 @@ class IfExp extends IfExp_ {
     result = this.getTest() or result = this.getBody() or result = this.getOrelse()
   }
 
-  override IfExprNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override IfExprNode getAFlowNode() { result = super.getAFlowNode() }
 }
 
 /** A starred expression, such as the `*rest` in the assignment `first, *rest = seq` */
@@ -411,7 +413,7 @@ class PlaceHolder extends PlaceHolder_ {
 
   override string toString() { result = "$" + this.getId() }
 
-  override NameNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override NameNode getAFlowNode() { result = super.getAFlowNode() }
 }
 
 /** A tuple expression such as `( 1, 3, 5, 7, 9 )` */
@@ -478,7 +480,7 @@ class Name extends Name_ {
 
   override string toString() { result = this.getId() }
 
-  override NameNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override NameNode getAFlowNode() { result = super.getAFlowNode() }
 
   override predicate isArtificial() {
     /* Artificial variable names in comprehensions all start with "." */
@@ -585,7 +587,7 @@ abstract class NameConstant extends Name, ImmutableLiteral {
 
   override predicate isConstant() { any() }
 
-  override NameConstantNode getAFlowNode() { result = Name.super.getAFlowNode() }
+  deprecated override NameConstantNode getAFlowNode() { result = Name.super.getAFlowNode() }
 
   override predicate isArtificial() { none() }
 }

python/ql/lib/semmle/python/Flow.qll

@@ -1,7 +1,7 @@
 overlay[local]
 module;
 
-import python
+import python as Py
 private import semmle.python.internal.CachedStages
 private import codeql.controlflow.BasicBlock as BB
 
@@ -17,7 +17,7 @@ private import codeql.controlflow.BasicBlock as BB
  */
 
 private predicate augstore(ControlFlowNode load, ControlFlowNode store) {
-  exists(Expr load_store | exists(AugAssign aa | aa.getTarget() = load_store) |
+  exists(Py::Expr load_store | exists(Py::AugAssign aa | aa.getTarget() = load_store) |
     toAst(load) = load_store and
     toAst(store) = load_store and
     load.strictlyDominates(store)
@@ -25,7 +25,7 @@ private predicate augstore(ControlFlowNode load, ControlFlowNode store) {
 }
 
 /** A non-dispatched getNode() to avoid negative recursion issues */
-private AstNode toAst(ControlFlowNode n) { py_flow_bb_node(n, result, _, _) }
+private Py::AstNode toAst(ControlFlowNode n) { py_flow_bb_node(n, result, _, _) }
 
 /**
  * A control flow node. Control flow nodes have a many-to-one relation with syntactic nodes,
@@ -35,19 +35,19 @@ private AstNode toAst(ControlFlowNode n) { py_flow_bb_node(n, result, _, _) }
 class ControlFlowNode extends @py_flow_node {
   /** Whether this control flow node is a load (including those in augmented assignments) */
   predicate isLoad() {
-    exists(Expr e | e = toAst(this) | py_expr_contexts(_, 3, e) and not augstore(_, this))
+    exists(Py::Expr e | e = toAst(this) | py_expr_contexts(_, 3, e) and not augstore(_, this))
   }
 
   /** Whether this control flow node is a store (including those in augmented assignments) */
   predicate isStore() {
-    exists(Expr e | e = toAst(this) | py_expr_contexts(_, 5, e) or augstore(_, this))
+    exists(Py::Expr e | e = toAst(this) | py_expr_contexts(_, 5, e) or augstore(_, this))
   }
 
   /** Whether this control flow node is a delete */
-  predicate isDelete() { exists(Expr e | e = toAst(this) | py_expr_contexts(_, 2, e)) }
+  predicate isDelete() { exists(Py::Expr e | e = toAst(this) | py_expr_contexts(_, 2, e)) }
 
   /** Whether this control flow node is a parameter */
-  predicate isParameter() { exists(Expr e | e = toAst(this) | py_expr_contexts(_, 4, e)) }
+  predicate isParameter() { exists(Py::Expr e | e = toAst(this) | py_expr_contexts(_, 4, e)) }
 
   /** Whether this control flow node is a store in an augmented assignment */
   predicate isAugStore() { augstore(_, this) }
@@ -57,61 +57,61 @@ class ControlFlowNode extends @py_flow_node {
 
   /** Whether this flow node corresponds to a literal */
   predicate isLiteral() {
-    toAst(this) instanceof Bytes
+    toAst(this) instanceof Py::Bytes
     or
-    toAst(this) instanceof Dict
+    toAst(this) instanceof Py::Dict
     or
-    toAst(this) instanceof DictComp
+    toAst(this) instanceof Py::DictComp
     or
-    toAst(this) instanceof Set
+    toAst(this) instanceof Py::Set
     or
-    toAst(this) instanceof SetComp
+    toAst(this) instanceof Py::SetComp
     or
-    toAst(this) instanceof Ellipsis
+    toAst(this) instanceof Py::Ellipsis
     or
-    toAst(this) instanceof GeneratorExp
+    toAst(this) instanceof Py::GeneratorExp
     or
-    toAst(this) instanceof Lambda
+    toAst(this) instanceof Py::Lambda
     or
-    toAst(this) instanceof ListComp
+    toAst(this) instanceof Py::ListComp
     or
-    toAst(this) instanceof List
+    toAst(this) instanceof Py::List
     or
-    toAst(this) instanceof Num
+    toAst(this) instanceof Py::Num
     or
-    toAst(this) instanceof Tuple
+    toAst(this) instanceof Py::Tuple
     or
-    toAst(this) instanceof Unicode
+    toAst(this) instanceof Py::Unicode
     or
-    toAst(this) instanceof NameConstant
+    toAst(this) instanceof Py::NameConstant
   }
 
   /** Whether this flow node corresponds to an attribute expression */
-  predicate isAttribute() { toAst(this) instanceof Attribute }
+  predicate isAttribute() { toAst(this) instanceof Py::Attribute }
 
   /** Whether this flow node corresponds to an subscript expression */
-  predicate isSubscript() { toAst(this) instanceof Subscript }
+  predicate isSubscript() { toAst(this) instanceof Py::Subscript }
 
   /** Whether this flow node corresponds to an import member */
-  predicate isImportMember() { toAst(this) instanceof ImportMember }
+  predicate isImportMember() { toAst(this) instanceof Py::ImportMember }
 
   /** Whether this flow node corresponds to a call */
-  predicate isCall() { toAst(this) instanceof Call }
+  predicate isCall() { toAst(this) instanceof Py::Call }
 
   /** Whether this flow node is the first in a module */
-  predicate isModuleEntry() { this.isEntryNode() and toAst(this) instanceof Module }
+  predicate isModuleEntry() { this.isEntryNode() and toAst(this) instanceof Py::Module }
 
   /** Whether this flow node corresponds to an import */
-  predicate isImport() { toAst(this) instanceof ImportExpr }
+  predicate isImport() { toAst(this) instanceof Py::ImportExpr }
 
   /** Whether this flow node corresponds to a conditional expression */
-  predicate isIfExp() { toAst(this) instanceof IfExp }
+  predicate isIfExp() { toAst(this) instanceof Py::IfExp }
 
   /** Whether this flow node corresponds to a function definition expression */
-  predicate isFunction() { toAst(this) instanceof FunctionExpr }
+  predicate isFunction() { toAst(this) instanceof Py::FunctionExpr }
 
   /** Whether this flow node corresponds to a class definition expression */
-  predicate isClass() { toAst(this) instanceof ClassExpr }
+  predicate isClass() { toAst(this) instanceof Py::ClassExpr }
 
   /** Gets a predecessor of this flow node */
   ControlFlowNode getAPredecessor() { this = result.getASuccessor() }
@@ -123,25 +123,25 @@ class ControlFlowNode extends @py_flow_node {
   ControlFlowNode getImmediateDominator() { py_idoms(this, result) }
 
   /** Gets the syntactic element corresponding to this flow node */
-  AstNode getNode() { py_flow_bb_node(this, result, _, _) }
+  Py::AstNode getNode() { py_flow_bb_node(this, result, _, _) }
 
   /** Gets a textual representation of this element. */
   cached
   string toString() {
     Stages::AST::ref() and
     // Since modules can have ambigous names, entry nodes can too, if we do not collate them.
-    exists(Scope s | s.getEntryNode() = this |
+    exists(Py::Scope s | s.getEntryNode() = this |
       result = "Entry node for " + concat( | | s.toString(), ",")
     )
     or
-    exists(Scope s | s.getANormalExit() = this | result = "Exit node for " + s.toString())
+    exists(Py::Scope s | s.getANormalExit() = this | result = "Exit node for " + s.toString())
     or
-    not exists(Scope s | s.getEntryNode() = this or s.getANormalExit() = this) and
+    not exists(Py::Scope s | s.getEntryNode() = this or s.getANormalExit() = this) and
     result = "ControlFlowNode for " + this.getNode().toString()
   }
 
   /** Gets the location of this ControlFlowNode */
-  Location getLocation() { result = this.getNode().getLocation() }
+  Py::Location getLocation() { result = this.getNode().getLocation() }
 
   /** Whether this flow node is the first in its scope */
   predicate isEntryNode() { py_scope_flow(this, _, -1) }
@@ -151,9 +151,9 @@ class ControlFlowNode extends @py_flow_node {
 
   /** Gets the scope containing this flow node */
   cached
-  Scope getScope() {
+  Py::Scope getScope() {
     Stages::AST::ref() and
-    if this.getNode() instanceof Scope
+    if this.getNode() instanceof Py::Scope
     then
       /* Entry or exit node */
       result = this.getNode()
@@ -161,7 +161,7 @@ class ControlFlowNode extends @py_flow_node {
   }
 
   /** Gets the enclosing module */
-  Module getEnclosingModule() { result = this.getScope().getEnclosingModule() }
+  Py::Module getEnclosingModule() { result = this.getScope().getEnclosingModule() }
 
   /** Gets a successor for this node if the relevant condition is True. */
   ControlFlowNode getATrueSuccessor() {
@@ -188,7 +188,7 @@ class ControlFlowNode extends @py_flow_node {
   }
 
   /** Whether the scope may be exited as a result of this node raising an exception */
-  predicate isExceptionalExit(Scope s) { py_scope_flow(this, s, 1) }
+  predicate isExceptionalExit(Py::Scope s) { py_scope_flow(this, s, 1) }
 
   /** Whether this node is a normal (non-exceptional) exit */
   predicate isNormalExit() { py_scope_flow(this, _, 0) or py_scope_flow(this, _, 2) }
@@ -236,7 +236,7 @@ class ControlFlowNode extends @py_flow_node {
   /* join-ordering helper for `getAChild() */
   pragma[noinline]
   private ControlFlowNode getExprChild(BasicBlock dom) {
-    this.getNode().(Expr).getAChildNode() = result.getNode() and
+    this.getNode().(Py::Expr).getAChildNode() = result.getNode() and
     result.getBasicBlock().dominates(dom) and
     not this instanceof UnaryExprNode
   }
@@ -249,16 +249,16 @@ class ControlFlowNode extends @py_flow_node {
  */
 
 private class AnyNode extends ControlFlowNode {
-  override AstNode getNode() { result = super.getNode() }
+  override Py::AstNode getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a call expression, such as `func(...)` */
 class CallNode extends ControlFlowNode {
-  CallNode() { toAst(this) instanceof Call }
+  CallNode() { toAst(this) instanceof Py::Call }
 
   /** Gets the flow node corresponding to the function expression for the call corresponding to this flow node */
   ControlFlowNode getFunction() {
-    exists(Call c |
+    exists(Py::Call c |
       this.getNode() = c and
       c.getFunc() = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -267,7 +267,7 @@ class CallNode extends ControlFlowNode {
 
   /** Gets the flow node corresponding to the n'th positional argument of the call corresponding to this flow node */
   ControlFlowNode getArg(int n) {
-    exists(Call c |
+    exists(Py::Call c |
       this.getNode() = c and
       c.getArg(n) = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -276,7 +276,7 @@ class CallNode extends ControlFlowNode {
 
   /** Gets the flow node corresponding to the named argument of the call corresponding to this flow node */
   ControlFlowNode getArgByName(string name) {
-    exists(Call c, Keyword k |
+    exists(Py::Call c, Py::Keyword k |
       this.getNode() = c and
       k = c.getANamedArg() and
       k.getValue() = result.getNode() and
@@ -292,7 +292,7 @@ class CallNode extends ControlFlowNode {
     result = this.getArgByName(_)
   }
 
-  override Call getNode() { result = super.getNode() }
+  override Py::Call getNode() { result = super.getNode() }
 
   predicate isDecoratorCall() {
     this.isClassDecoratorCall()
@@ -301,11 +301,11 @@ class CallNode extends ControlFlowNode {
   }
 
   predicate isClassDecoratorCall() {
-    exists(ClassExpr cls | this.getNode() = cls.getADecoratorCall())
+    exists(Py::ClassExpr cls | this.getNode() = cls.getADecoratorCall())
   }
 
   predicate isFunctionDecoratorCall() {
-    exists(FunctionExpr func | this.getNode() = func.getADecoratorCall())
+    exists(Py::FunctionExpr func | this.getNode() = func.getADecoratorCall())
   }
 
   /** Gets the first tuple (*) argument of this call, if any. */
@@ -323,11 +323,11 @@ class CallNode extends ControlFlowNode {
 
 /** A control flow corresponding to an attribute expression, such as `value.attr` */
 class AttrNode extends ControlFlowNode {
-  AttrNode() { toAst(this) instanceof Attribute }
+  AttrNode() { toAst(this) instanceof Py::Attribute }
 
   /** Gets the flow node corresponding to the object of the attribute expression corresponding to this flow node */
   ControlFlowNode getObject() {
-    exists(Attribute a |
+    exists(Py::Attribute a |
       this.getNode() = a and
       a.getObject() = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -339,7 +339,7 @@ class AttrNode extends ControlFlowNode {
    * with the matching name
    */
   ControlFlowNode getObject(string name) {
-    exists(Attribute a |
+    exists(Py::Attribute a |
       this.getNode() = a and
       a.getObject() = result.getNode() and
       a.getName() = name and
@@ -348,57 +348,57 @@ class AttrNode extends ControlFlowNode {
   }
 
   /** Gets the attribute name of the attribute expression corresponding to this flow node */
-  string getName() { exists(Attribute a | this.getNode() = a and a.getName() = result) }
+  string getName() { exists(Py::Attribute a | this.getNode() = a and a.getName() = result) }
 
-  override Attribute getNode() { result = super.getNode() }
+  override Py::Attribute getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a `from ... import ...` expression */
 class ImportMemberNode extends ControlFlowNode {
-  ImportMemberNode() { toAst(this) instanceof ImportMember }
+  ImportMemberNode() { toAst(this) instanceof Py::ImportMember }
 
   /**
    * Gets the flow node corresponding to the module in the import-member expression corresponding to this flow node,
    * with the matching name
    */
   ControlFlowNode getModule(string name) {
-    exists(ImportMember i | this.getNode() = i and i.getModule() = result.getNode() |
+    exists(Py::ImportMember i | this.getNode() = i and i.getModule() = result.getNode() |
       i.getName() = name and
       result.getBasicBlock().dominates(this.getBasicBlock())
     )
   }
 
-  override ImportMember getNode() { result = super.getNode() }
+  override Py::ImportMember getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to an artificial expression representing an import */
 class ImportExprNode extends ControlFlowNode {
-  ImportExprNode() { toAst(this) instanceof ImportExpr }
+  ImportExprNode() { toAst(this) instanceof Py::ImportExpr }
 
-  override ImportExpr getNode() { result = super.getNode() }
+  override Py::ImportExpr getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a `from ... import *` statement */
 class ImportStarNode extends ControlFlowNode {
-  ImportStarNode() { toAst(this) instanceof ImportStar }
+  ImportStarNode() { toAst(this) instanceof Py::ImportStar }
 
   /** Gets the flow node corresponding to the module in the import-star corresponding to this flow node */
   ControlFlowNode getModule() {
-    exists(ImportStar i | this.getNode() = i and i.getModuleExpr() = result.getNode() |
+    exists(Py::ImportStar i | this.getNode() = i and i.getModuleExpr() = result.getNode() |
       result.getBasicBlock().dominates(this.getBasicBlock())
     )
   }
 
-  override ImportStar getNode() { result = super.getNode() }
+  override Py::ImportStar getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a subscript expression, such as `value[slice]` */
 class SubscriptNode extends ControlFlowNode {
-  SubscriptNode() { toAst(this) instanceof Subscript }
+  SubscriptNode() { toAst(this) instanceof Py::Subscript }
 
   /** flow node corresponding to the value of the sequence in a subscript operation */
   ControlFlowNode getObject() {
-    exists(Subscript s |
+    exists(Py::Subscript s |
       this.getNode() = s and
       s.getObject() = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -407,23 +407,23 @@ class SubscriptNode extends ControlFlowNode {
 
   /** flow node corresponding to the index in a subscript operation */
   ControlFlowNode getIndex() {
-    exists(Subscript s |
+    exists(Py::Subscript s |
       this.getNode() = s and
       s.getIndex() = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
     )
   }
 
-  override Subscript getNode() { result = super.getNode() }
+  override Py::Subscript getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a comparison operation, such as `x<y` */
 class CompareNode extends ControlFlowNode {
-  CompareNode() { toAst(this) instanceof Compare }
+  CompareNode() { toAst(this) instanceof Py::Compare }
 
   /** Whether left and right are a pair of operands for this comparison */
-  predicate operands(ControlFlowNode left, Cmpop op, ControlFlowNode right) {
+  predicate operands(ControlFlowNode left, Py::Cmpop op, ControlFlowNode right) {
-    exists(Compare c, Expr eleft, Expr eright |
+    exists(Py::Compare c, Py::Expr eleft, Py::Expr eright |
       this.getNode() = c and left.getNode() = eleft and right.getNode() = eright
     |
       eleft = c.getLeft() and eright = c.getComparator(0) and op = c.getOp(0)
@@ -436,26 +436,26 @@ class CompareNode extends ControlFlowNode {
     right.getBasicBlock().dominates(this.getBasicBlock())
   }
 
-  override Compare getNode() { result = super.getNode() }
+  override Py::Compare getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a conditional expression such as, `body if test else orelse` */
 class IfExprNode extends ControlFlowNode {
-  IfExprNode() { toAst(this) instanceof IfExp }
+  IfExprNode() { toAst(this) instanceof Py::IfExp }
 
   /** flow node corresponding to one of the operands of an if-expression */
   ControlFlowNode getAnOperand() { result = this.getAPredecessor() }
 
-  override IfExp getNode() { result = super.getNode() }
+  override Py::IfExp getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to an assignment expression such as `lhs := rhs`. */
 class AssignmentExprNode extends ControlFlowNode {
-  AssignmentExprNode() { toAst(this) instanceof AssignExpr }
+  AssignmentExprNode() { toAst(this) instanceof Py::AssignExpr }
 
   /** Gets the flow node corresponding to the left-hand side of the assignment expression */
   ControlFlowNode getTarget() {
-    exists(AssignExpr a |
+    exists(Py::AssignExpr a |
       this.getNode() = a and
       a.getTarget() = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -464,27 +464,27 @@ class AssignmentExprNode extends ControlFlowNode {
 
   /** Gets the flow node corresponding to the right-hand side of the assignment expression */
   ControlFlowNode getValue() {
-    exists(AssignExpr a |
+    exists(Py::AssignExpr a |
       this.getNode() = a and
       a.getValue() = result.getNode() and
       result.getBasicBlock().dominates(this.getBasicBlock())
     )
   }
 
-  override AssignExpr getNode() { result = super.getNode() }
+  override Py::AssignExpr getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a binary expression, such as `x + y` */
 class BinaryExprNode extends ControlFlowNode {
-  BinaryExprNode() { toAst(this) instanceof BinaryExpr }
+  BinaryExprNode() { toAst(this) instanceof Py::BinaryExpr }
 
   /** flow node corresponding to one of the operands of a binary expression */
   ControlFlowNode getAnOperand() { result = this.getLeft() or result = this.getRight() }
 
-  override BinaryExpr getNode() { result = super.getNode() }
+  override Py::BinaryExpr getNode() { result = super.getNode() }
 
   ControlFlowNode getLeft() {
-    exists(BinaryExpr b |
+    exists(Py::BinaryExpr b |
       this.getNode() = b and
       result.getNode() = b.getLeft() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -492,7 +492,7 @@ class BinaryExprNode extends ControlFlowNode {
   }
 
   ControlFlowNode getRight() {
-    exists(BinaryExpr b |
+    exists(Py::BinaryExpr b |
       this.getNode() = b and
       result.getNode() = b.getRight() and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -500,11 +500,11 @@ class BinaryExprNode extends ControlFlowNode {
   }
 
   /** Gets the operator of this binary expression node. */
-  Operator getOp() { result = this.getNode().getOp() }
+  Py::Operator getOp() { result = this.getNode().getOp() }
 
   /** Whether left and right are a pair of operands for this binary expression */
-  predicate operands(ControlFlowNode left, Operator op, ControlFlowNode right) {
+  predicate operands(ControlFlowNode left, Py::Operator op, ControlFlowNode right) {
-    exists(BinaryExpr b, Expr eleft, Expr eright |
+    exists(Py::BinaryExpr b, Py::Expr eleft, Py::Expr eright |
       this.getNode() = b and left.getNode() = eleft and right.getNode() = eright
     |
       eleft = b.getLeft() and eright = b.getRight() and op = b.getOp()
@@ -516,20 +516,20 @@ class BinaryExprNode extends ControlFlowNode {
 
 /** A control flow node corresponding to a boolean shortcut (and/or) operation */
 class BoolExprNode extends ControlFlowNode {
-  BoolExprNode() { toAst(this) instanceof BoolExpr }
+  BoolExprNode() { toAst(this) instanceof Py::BoolExpr }
 
   /** flow node corresponding to one of the operands of a boolean expression */
   ControlFlowNode getAnOperand() {
-    exists(BoolExpr b | this.getNode() = b and result.getNode() = b.getAValue()) and
+    exists(Py::BoolExpr b | this.getNode() = b and result.getNode() = b.getAValue()) and
     this.getBasicBlock().dominates(result.getBasicBlock())
   }
 
-  override BoolExpr getNode() { result = super.getNode() }
+  override Py::BoolExpr getNode() { result = super.getNode() }
 }
 
 /** A control flow node corresponding to a unary expression: (`+x`), (`-x`) or (`~x`) */
 class UnaryExprNode extends ControlFlowNode {
-  UnaryExprNode() { toAst(this) instanceof UnaryExpr }
+  UnaryExprNode() { toAst(this) instanceof Py::UnaryExpr }
 
   /**
    * Gets flow node corresponding to the operand of a unary expression.
@@ -540,7 +540,7 @@ class UnaryExprNode extends ControlFlowNode {
    */
   ControlFlowNode getOperand() { result = this.getAPredecessor() }
 
-  override UnaryExpr getNode() { result = super.getNode() }
+  override Py::UnaryExpr getNode() { result = super.getNode() }
 
   override ControlFlowNode getAChild() { result = this.getAPredecessor() }
 }
@@ -555,27 +555,27 @@ class DefinitionNode extends ControlFlowNode {
   cached
   DefinitionNode() {
     Stages::AST::ref() and
-    exists(Assign a | a.getATarget().getAFlowNode() = this)
+    exists(Py::Assign a | this.getNode() = a.getATarget())
     or
-    exists(AssignExpr a | a.getTarget().getAFlowNode() = this)
+    exists(Py::AssignExpr a | this.getNode() = a.getTarget())
     or
-    exists(AnnAssign a | a.getTarget().getAFlowNode() = this and exists(a.getValue()))
+    exists(Py::AnnAssign a | this.getNode() = a.getTarget() and exists(a.getValue()))
     or
-    exists(Alias a | a.getAsname().getAFlowNode() = this)
+    exists(Py::Alias a | this.getNode() = a.getAsname())
     or
     augstore(_, this)
     or
     // `x, y = 1, 2` where LHS is a combination of list or tuples
-    exists(Assign a | list_or_tuple_nested_element(a.getATarget()).getAFlowNode() = this)
+    exists(Py::Assign a | this.getNode() = list_or_tuple_nested_element(a.getATarget()))
     or
-    exists(For for | for.getTarget().getAFlowNode() = this)
+    exists(Py::For for | this.getNode() = for.getTarget())
     or
-    exists(Parameter param | this = param.asName().getAFlowNode() and exists(param.getDefault()))
+    exists(Py::Parameter param | this.getNode() = param.asName() and exists(param.getDefault()))
   }
 
   /** flow node corresponding to the value assigned for the definition corresponding to this flow node */
   ControlFlowNode getValue() {
-    result = assigned_value(this.getNode()).getAFlowNode() and
+    result.getNode() = assigned_value(this.getNode()) and
     (
       result.getBasicBlock().dominates(this.getBasicBlock())
       or
@@ -584,16 +584,16 @@ class DefinitionNode extends ControlFlowNode {
       // since the default value for a parameter is evaluated in the same basic block as
       // the function definition, but the parameter belongs to the basic block of the function,
       // there is no dominance relationship between the two.
-      exists(Parameter param | this = param.asName().getAFlowNode())
+      exists(Py::Parameter param | this.getNode() = param.asName())
     )
   }
 }
 
-private Expr list_or_tuple_nested_element(Expr list_or_tuple) {
+private Py::Expr list_or_tuple_nested_element(Py::Expr list_or_tuple) {
-  exists(Expr elt |
+  exists(Py::Expr elt |
-    elt = list_or_tuple.(Tuple).getAnElt()
+    elt = list_or_tuple.(Py::Tuple).getAnElt()
     or
-    elt = list_or_tuple.(List).getAnElt()
+    elt = list_or_tuple.(Py::List).getAnElt()
   |
     result = elt
     or
@@ -603,12 +603,12 @@ private Expr list_or_tuple_nested_element(Expr list_or_tuple) {
 
 /**
  * A control flow node corresponding to a deletion statement, such as `del x`.
- * There can be multiple `DeletionNode`s for each `Delete` such that each
+ * There can be multiple `DeletionNode`s for each `Py::Delete` such that each
  * target has own `DeletionNode`. The CFG for `del a, x.y` looks like:
  * `NameNode('a') -> DeletionNode -> NameNode('b') -> AttrNode('y') -> DeletionNode`.
  */
 class DeletionNode extends ControlFlowNode {
-  DeletionNode() { toAst(this) instanceof Delete }
+  DeletionNode() { toAst(this) instanceof Py::Delete }
 
   /** Gets the unique target of this deletion node. */
   ControlFlowNode getTarget() { result.getASuccessor() = this }
@@ -617,9 +617,9 @@ class DeletionNode extends ControlFlowNode {
 /** A control flow node corresponding to a sequence (tuple or list) literal */
 abstract class SequenceNode extends ControlFlowNode {
   SequenceNode() {
-    toAst(this) instanceof Tuple
+    toAst(this) instanceof Py::Tuple
     or
-    toAst(this) instanceof List
+    toAst(this) instanceof Py::List
   }
 
   /** Gets the control flow node for an element of this sequence */
@@ -632,11 +632,11 @@ abstract class SequenceNode extends ControlFlowNode {
 
 /** A control flow node corresponding to a tuple expression such as `( 1, 3, 5, 7, 9 )` */
 class TupleNode extends SequenceNode {
-  TupleNode() { toAst(this) instanceof Tuple }
+  TupleNode() { toAst(this) instanceof Py::Tuple }
 
   override ControlFlowNode getElement(int n) {
     Stages::AST::ref() and
-    exists(Tuple t | this.getNode() = t and result.getNode() = t.getElt(n)) and
+    exists(Py::Tuple t | this.getNode() = t and result.getNode() = t.getElt(n)) and
     (
       result.getBasicBlock().dominates(this.getBasicBlock())
       or
@@ -647,10 +647,10 @@ class TupleNode extends SequenceNode {
 
 /** A control flow node corresponding to a list expression, such as `[ 1, 3, 5, 7, 9 ]` */
 class ListNode extends SequenceNode {
-  ListNode() { toAst(this) instanceof List }
+  ListNode() { toAst(this) instanceof Py::List }
 
   override ControlFlowNode getElement(int n) {
-    exists(List l | this.getNode() = l and result.getNode() = l.getElt(n)) and
+    exists(Py::List l | this.getNode() = l and result.getNode() = l.getElt(n)) and
     (
       result.getBasicBlock().dominates(this.getBasicBlock())
       or
@@ -661,10 +661,10 @@ class ListNode extends SequenceNode {
 
 /** A control flow node corresponding to a set expression, such as `{ 1, 3, 5, 7, 9 }` */
 class SetNode extends ControlFlowNode {
-  SetNode() { toAst(this) instanceof Set }
+  SetNode() { toAst(this) instanceof Py::Set }
 
   ControlFlowNode getAnElement() {
-    exists(Set s | this.getNode() = s and result.getNode() = s.getElt(_)) and
+    exists(Py::Set s | this.getNode() = s and result.getNode() = s.getElt(_)) and
     (
       result.getBasicBlock().dominates(this.getBasicBlock())
       or
@@ -675,20 +675,20 @@ class SetNode extends ControlFlowNode {
 
 /** A control flow node corresponding to a dictionary literal, such as `{ 'a': 1, 'b': 2 }` */
 class DictNode extends ControlFlowNode {
-  DictNode() { toAst(this) instanceof Dict }
+  DictNode() { toAst(this) instanceof Py::Dict }
 
   /**
    * Gets a key of this dictionary literal node, for those items that have keys
    * E.g, in {'a':1, **b} this returns only 'a'
    */
   ControlFlowNode getAKey() {
-    exists(Dict d | this.getNode() = d and result.getNode() = d.getAKey()) and
+    exists(Py::Dict d | this.getNode() = d and result.getNode() = d.getAKey()) and
     result.getBasicBlock().dominates(this.getBasicBlock())
   }
 
   /** Gets a value of this dictionary literal node */
   ControlFlowNode getAValue() {
-    exists(Dict d | this.getNode() = d and result.getNode() = d.getAValue()) and
+    exists(Py::Dict d | this.getNode() = d and result.getNode() = d.getAValue()) and
     result.getBasicBlock().dominates(this.getBasicBlock())
   }
 }
@@ -712,21 +712,23 @@ class IterableNode extends ControlFlowNode {
   }
 }
 
-private AstNode assigned_value(Expr lhs) {
+private Py::AstNode assigned_value(Py::Expr lhs) {
   /* lhs = result */
-  exists(Assign a | a.getATarget() = lhs and result = a.getValue())
+  exists(Py::Assign a | a.getATarget() = lhs and result = a.getValue())
   or
   /* lhs := result */
-  exists(AssignExpr a | a.getTarget() = lhs and result = a.getValue())
+  exists(Py::AssignExpr a | a.getTarget() = lhs and result = a.getValue())
   or
   /* lhs : annotation = result */
-  exists(AnnAssign a | a.getTarget() = lhs and result = a.getValue())
+  exists(Py::AnnAssign a | a.getTarget() = lhs and result = a.getValue())
   or
   /* import result as lhs */
-  exists(Alias a | a.getAsname() = lhs and result = a.getValue())
+  exists(Py::Alias a | a.getAsname() = lhs and result = a.getValue())
   or
   /* lhs += x  =>  result = (lhs + x) */
-  exists(AugAssign a, BinaryExpr b | b = a.getOperation() and result = b and lhs = b.getLeft())
+  exists(Py::AugAssign a, Py::BinaryExpr b |
+    b = a.getOperation() and result = b and lhs = b.getLeft()
+  )
   or
   /*
    * ..., lhs, ... = ..., result, ...
@@ -734,31 +736,31 @@ private AstNode assigned_value(Expr lhs) {
    * ..., (..., lhs, ...), ... = ..., (..., result, ...), ...
    */
 
-  exists(Assign a | nested_sequence_assign(a.getATarget(), a.getValue(), lhs, result))
+  exists(Py::Assign a | nested_sequence_assign(a.getATarget(), a.getValue(), lhs, result))
   or
   /* for lhs in seq: => `result` is the `for` node, representing the `iter(next(seq))` operation. */
-  result.(For).getTarget() = lhs
+  result.(Py::For).getTarget() = lhs
   or
-  exists(Parameter param | lhs = param.asName() and result = param.getDefault())
+  exists(Py::Parameter param | lhs = param.asName() and result = param.getDefault())
 }
 
 predicate nested_sequence_assign(
-  Expr left_parent, Expr right_parent, Expr left_result, Expr right_result
+  Py::Expr left_parent, Py::Expr right_parent, Py::Expr left_result, Py::Expr right_result
 ) {
-  exists(Assign a |
+  exists(Py::Assign a |
     a.getATarget().getASubExpression*() = left_parent and
     a.getValue().getASubExpression*() = right_parent
   ) and
-  exists(int i, Expr left_elem, Expr right_elem |
+  exists(int i, Py::Expr left_elem, Py::Expr right_elem |
     (
-      left_elem = left_parent.(Tuple).getElt(i)
+      left_elem = left_parent.(Py::Tuple).getElt(i)
       or
-      left_elem = left_parent.(List).getElt(i)
+      left_elem = left_parent.(Py::List).getElt(i)
     ) and
     (
-      right_elem = right_parent.(Tuple).getElt(i)
+      right_elem = right_parent.(Py::Tuple).getElt(i)
       or
-      right_elem = right_parent.(List).getElt(i)
+      right_elem = right_parent.(Py::List).getElt(i)
     )
   |
     left_result = left_elem and right_result = right_elem
@@ -769,9 +771,9 @@ predicate nested_sequence_assign(
 
 /** A flow node for a `for` statement. */
 class ForNode extends ControlFlowNode {
-  ForNode() { toAst(this) instanceof For }
+  ForNode() { toAst(this) instanceof Py::For }
 
-  override For getNode() { result = super.getNode() }
+  override Py::For getNode() { result = super.getNode() }
 
   /** Holds if this `for` statement causes iteration over `sequence` storing each step of the iteration in `target` */
   predicate iterates(ControlFlowNode target, ControlFlowNode sequence) {
@@ -782,7 +784,7 @@ class ForNode extends ControlFlowNode {
 
   /** Gets the sequence node for this `for` statement. */
   ControlFlowNode getSequence() {
-    exists(For for |
+    exists(Py::For for |
       toAst(this) = for and
       for.getIter() = result.getNode()
     |
@@ -792,7 +794,7 @@ class ForNode extends ControlFlowNode {
 
   /** A possible `target` for this `for` statement, not accounting for loop unrolling */
   private ControlFlowNode possibleTarget() {
-    exists(For for |
+    exists(Py::For for |
       toAst(this) = for and
       for.getTarget() = result.getNode() and
       this.getBasicBlock().dominates(result.getBasicBlock())
@@ -809,11 +811,11 @@ class ForNode extends ControlFlowNode {
 
 /** A flow node for a `raise` statement */
 class RaiseStmtNode extends ControlFlowNode {
-  RaiseStmtNode() { toAst(this) instanceof Raise }
+  RaiseStmtNode() { toAst(this) instanceof Py::Raise }
 
   /** Gets the control flow node for the exception raised by this raise statement */
   ControlFlowNode getException() {
-    exists(Raise r |
+    exists(Py::Raise r |
       r = toAst(this) and
       r.getException() = toAst(result) and
       result.getBasicBlock().dominates(this.getBasicBlock())
@@ -827,36 +829,36 @@ class RaiseStmtNode extends ControlFlowNode {
  */
 class NameNode extends ControlFlowNode {
   NameNode() {
-    exists(Name n | py_flow_bb_node(this, n, _, _))
+    exists(Py::Name n | py_flow_bb_node(this, n, _, _))
     or
-    exists(PlaceHolder p | py_flow_bb_node(this, p, _, _))
+    exists(Py::PlaceHolder p | py_flow_bb_node(this, p, _, _))
   }
 
   /** Whether this flow node defines the variable `v`. */
-  predicate defines(Variable v) {
+  predicate defines(Py::Variable v) {
-    exists(Name d | this.getNode() = d and d.defines(v)) and
+    exists(Py::Name d | this.getNode() = d and d.defines(v)) and
     not this.isLoad()
   }
 
   /** Whether this flow node deletes the variable `v`. */
-  predicate deletes(Variable v) { exists(Name d | this.getNode() = d and d.deletes(v)) }
+  predicate deletes(Py::Variable v) { exists(Py::Name d | this.getNode() = d and d.deletes(v)) }
 
   /** Whether this flow node uses the variable `v`. */
-  predicate uses(Variable v) {
+  predicate uses(Py::Variable v) {
     this.isLoad() and
-    exists(Name u | this.getNode() = u and u.uses(v))
+    exists(Py::Name u | this.getNode() = u and u.uses(v))
     or
-    exists(PlaceHolder u |
+    exists(Py::PlaceHolder u |
-      this.getNode() = u and u.getVariable() = v and u.getCtx() instanceof Load
+      this.getNode() = u and u.getVariable() = v and u.getCtx() instanceof Py::Load
     )
     or
     Scopes::use_of_global_variable(this, v.getScope(), v.getId())
   }
 
   string getId() {
-    result = this.getNode().(Name).getId()
+    result = this.getNode().(Py::Name).getId()
     or
-    result = this.getNode().(PlaceHolder).getId()
+    result = this.getNode().(Py::PlaceHolder).getId()
   }
 
   /** Whether this is a use of a local variable. */
@@ -868,82 +870,84 @@ class NameNode extends ControlFlowNode {
   /** Whether this is a use of a global (including builtin) variable. */
   predicate isGlobal() { Scopes::use_of_global_variable(this, _, _) }
 
-  predicate isSelf() { exists(SsaVariable selfvar | selfvar.isSelf() and selfvar.getAUse() = this) }
+  predicate isSelf() {
+    exists(Py::SsaVariable selfvar | selfvar.isSelf() and selfvar.getAUse() = this)
+  }
 }
 
 /** A control flow node corresponding to a named constant, one of `None`, `True` or `False`. */
 class NameConstantNode extends NameNode {
-  NameConstantNode() { exists(NameConstant n | py_flow_bb_node(this, n, _, _)) }
+  NameConstantNode() { exists(Py::NameConstant n | py_flow_bb_node(this, n, _, _)) }
   /*
    * We ought to override uses as well, but that has
    * a serious performance impact.
-   *    deprecated predicate uses(Variable v) { none() }
+   *    deprecated predicate uses(Py::Variable v) { none() }
    */
 
   }
 
 /** A control flow node corresponding to a starred expression, `*a`. */
 class StarredNode extends ControlFlowNode {
-  StarredNode() { toAst(this) instanceof Starred }
+  StarredNode() { toAst(this) instanceof Py::Starred }
 
-  ControlFlowNode getValue() { toAst(result) = toAst(this).(Starred).getValue() }
+  ControlFlowNode getValue() { toAst(result) = toAst(this).(Py::Starred).getValue() }
 }
 
 /** The ControlFlowNode for an 'except' statement. */
 class ExceptFlowNode extends ControlFlowNode {
-  ExceptFlowNode() { this.getNode() instanceof ExceptStmt }
+  ExceptFlowNode() { this.getNode() instanceof Py::ExceptStmt }
 
   /**
    * Gets the type handled by this exception handler.
-   * `ExceptionType` in `except ExceptionType as e:`
+   * `Py::ExceptionType` in `except Py::ExceptionType as e:`
    */
   ControlFlowNode getType() {
-    exists(ExceptStmt ex |
+    exists(Py::ExceptStmt ex |
       this.getBasicBlock().dominates(result.getBasicBlock()) and
       ex = this.getNode() and
-      result = ex.getType().getAFlowNode()
+      result.getNode() = ex.getType()
     )
   }
 
   /**
    * Gets the name assigned to the handled exception, if any.
-   * `e` in `except ExceptionType as e:`
+   * `e` in `except Py::ExceptionType as e:`
    */
   ControlFlowNode getName() {
-    exists(ExceptStmt ex |
+    exists(Py::ExceptStmt ex |
       this.getBasicBlock().dominates(result.getBasicBlock()) and
       ex = this.getNode() and
-      result = ex.getName().getAFlowNode()
+      result.getNode() = ex.getName()
     )
   }
 }
 
 /** The ControlFlowNode for an 'except*' statement. */
 class ExceptGroupFlowNode extends ControlFlowNode {
-  ExceptGroupFlowNode() { this.getNode() instanceof ExceptGroupStmt }
+  ExceptGroupFlowNode() { this.getNode() instanceof Py::ExceptGroupStmt }
 
   /**
    * Gets the type handled by this exception handler.
-   * `ExceptionType` in `except* ExceptionType as e:`
+   * `Py::ExceptionType` in `except* Py::ExceptionType as e:`
    */
   ControlFlowNode getType() {
     this.getBasicBlock().dominates(result.getBasicBlock()) and
-    result = this.getNode().(ExceptGroupStmt).getType().getAFlowNode()
+    result.getNode() = this.getNode().(Py::ExceptGroupStmt).getType()
   }
 
   /**
    * Gets the name assigned to the handled exception, if any.
-   * `e` in `except* ExceptionType as e:`
+   * `e` in `except* Py::ExceptionType as e:`
    */
   ControlFlowNode getName() {
     this.getBasicBlock().dominates(result.getBasicBlock()) and
-    result = this.getNode().(ExceptGroupStmt).getName().getAFlowNode()
+    result.getNode() = this.getNode().(Py::ExceptGroupStmt).getName()
   }
 }
 
 private module Scopes {
   private predicate fast_local(NameNode n) {
-    exists(FastLocalVariable v |
+    exists(Py::FastLocalVariable v |
       n.uses(v) and
       v.getScope() = n.getScope()
     )
@@ -952,15 +956,15 @@ private module Scopes {
   predicate local(NameNode n) {
     fast_local(n)
     or
-    exists(SsaVariable var |
+    exists(Py::SsaVariable var |
       var.getAUse() = n and
-      n.getScope() instanceof Class and
+      n.getScope() instanceof Py::Class and
       exists(var.getDefinition())
     )
   }
 
   predicate non_local(NameNode n) {
-    exists(FastLocalVariable flv |
+    exists(Py::FastLocalVariable flv |
       flv.getALoad() = n.getNode() and
       not flv.getScope() = n.getScope()
     )
@@ -968,20 +972,20 @@ private module Scopes {
 
   // magic is fine, but we get questionable join-ordering of it
   pragma[nomagic]
-  predicate use_of_global_variable(NameNode n, Module scope, string name) {
+  predicate use_of_global_variable(NameNode n, Py::Module scope, string name) {
     n.isLoad() and
     not non_local(n) and
-    not exists(SsaVariable var | var.getAUse() = n |
+    not exists(Py::SsaVariable var | var.getAUse() = n |
-      var.getVariable() instanceof FastLocalVariable
+      var.getVariable() instanceof Py::FastLocalVariable
       or
-      n.getScope() instanceof Class and
+      n.getScope() instanceof Py::Class and
       not maybe_undefined(var)
     ) and
     name = n.getId() and
     scope = n.getEnclosingModule()
   }
 
-  private predicate maybe_undefined(SsaVariable var) {
+  private predicate maybe_undefined(Py::SsaVariable var) {
     not exists(var.getDefinition()) and not py_ssa_phi(var, _)
     or
     var.getDefinition().isDelete()
@@ -1058,13 +1062,13 @@ class BasicBlock extends @py_flow_node {
   private predicate oneNodeBlock() { this.firstNode() = this.getLastNode() }
 
   private predicate startLocationInfo(string file, int line, int col) {
-    if this.firstNode().getNode() instanceof Scope
+    if this.firstNode().getNode() instanceof Py::Scope
     then this.firstNode().getASuccessor().getLocation().hasLocationInfo(file, line, col, _, _)
     else this.firstNode().getLocation().hasLocationInfo(file, line, col, _, _)
   }
 
   private predicate endLocationInfo(int endl, int endc) {
-    if this.getLastNode().getNode() instanceof Scope and not this.oneNodeBlock()
+    if this.getLastNode().getNode() instanceof Py::Scope and not this.oneNodeBlock()
     then this.getLastNode().getAPredecessor().getLocation().hasLocationInfo(_, _, _, endl, endc)
     else this.getLastNode().getLocation().hasLocationInfo(_, _, _, endl, endc)
   }
@@ -1081,7 +1085,7 @@ class BasicBlock extends @py_flow_node {
 
   /** Whether flow from this basic block reaches a normal exit from its scope */
   predicate reachesExit() {
-    exists(Scope s | s.getANormalExit().getBasicBlock() = this)
+    exists(Py::Scope s | s.getANormalExit().getBasicBlock() = this)
     or
     this.getASuccessor().reachesExit()
   }
@@ -1122,7 +1126,7 @@ class BasicBlock extends @py_flow_node {
 
   /** Gets the scope of this block */
   pragma[nomagic]
-  Scope getScope() {
+  Py::Scope getScope() {
     exists(ControlFlowNode n | n.getBasicBlock() = this |
       /* Take care not to use an entry or exit node as that node's scope will be the outer scope */
       not py_scope_flow(n, _, -1) and
@@ -1145,17 +1149,17 @@ class BasicBlock extends @py_flow_node {
   predicate reaches(BasicBlock other) { this = other or this.strictlyReaches(other) }
 
   /**
-   * Gets the `ConditionBlock`, if any, that controls this block and
+   * Gets the `Py::ConditionBlock`, if any, that controls this block and
-   * does not control any other `ConditionBlock`s that control this block.
+   * does not control any other `Py::ConditionBlock`s that control this block.
-   * That is the `ConditionBlock` that is closest dominator.
+   * That is the `Py::ConditionBlock` that is closest dominator.
    */
-  ConditionBlock getImmediatelyControllingBlock() {
+  Py::ConditionBlock getImmediatelyControllingBlock() {
     result = this.nonControllingImmediateDominator*().getImmediateDominator()
   }
 
   private BasicBlock nonControllingImmediateDominator() {
     result = this.getImmediateDominator() and
-    not result.(ConditionBlock).controls(this, _)
+    not result.(Py::ConditionBlock).controls(this, _)
   }
 
   /**
@@ -1175,7 +1179,7 @@ private class ControlFlowNodeAlias = ControlFlowNode;
 
 final private class FinalBasicBlock = BasicBlock;
 
-module Cfg implements BB::CfgSig<Location> {
+module Cfg implements BB::CfgSig<Py::Location> {
   private import codeql.controlflow.SuccessorType
 
   class ControlFlowNode = ControlFlowNodeAlias;
@@ -1186,7 +1190,7 @@ module Cfg implements BB::CfgSig<Location> {
     // Using the location of the first node is simple
     // and we just need a way to identify the basic block
     // during debugging, so this will be serviceable.
-    Location getLocation() { result = super.getNode(0).getLocation() }
+    Py::Location getLocation() { result = super.getNode(0).getLocation() }
 
     int length() { result = count(int i | exists(this.getNode(i))) }
 

python/ql/lib/semmle/python/Function.qll

@@ -153,8 +153,16 @@ class Function extends Function_, Scope, AstNode {
 
   override predicate contains(AstNode inner) { Scope.super.contains(inner) }
 
-  /** Gets a control flow node for a return value of this function */
+  /**
-  ControlFlowNode getAReturnValueFlowNode() {
+   * DEPRECATED: bind a `Return` node explicitly instead, e.g.
+   * `exists(Return ret | ret.getScope() = this and n.getNode() = ret.getValue())`.
+   * This API is being phased out together with `AstNode.getAFlowNode()` to
+   * untangle the AST and CFG hierarchies in preparation for migrating the
+   * dataflow library off the legacy CFG.
+   *
+   * Gets a control flow node for a return value of this function.
+   */
+  deprecated ControlFlowNode getAReturnValueFlowNode() {
     exists(Return ret |
       ret.getScope() = this and
       ret.getValue() = result.getNode()

python/ql/lib/semmle/python/Import.qll

@@ -163,7 +163,7 @@ class ImportMember extends ImportMember_ {
     result = this.getModule().(ImportExpr).getImportedModuleName() + "." + this.getName()
   }
 
-  override ImportMemberNode getAFlowNode() { result = super.getAFlowNode() }
+  deprecated override ImportMemberNode getAFlowNode() { result = super.getAFlowNode() }
 }
 
 /** An import statement */

python/ql/lib/semmle/python/SelfAttribute.qll

@@ -46,20 +46,23 @@ class SelfAttributeRead extends SelfAttribute {
   }
 
   predicate guardedByHasattr() {
-    exists(Variable var, ControlFlowNode n |
+    exists(Variable var, ControlFlowNode n, ControlFlowNode this_, ControlFlowNode obj_ |
-      var.getAUse() = this.getObject().getAFlowNode() and
+      this_.getNode() = this and obj_.getNode() = this.getObject()
+    |
+      var.getAUse() = obj_ and
       hasattr(n, var.getAUse(), this.getName()) and
-      n.strictlyDominates(this.getAFlowNode())
+      n.strictlyDominates(this_)
     )
   }
 
   pragma[noinline]
   predicate locallyDefined() {
-    exists(SelfAttributeStore store |
+    exists(SelfAttributeStore store, ControlFlowNode store_, ControlFlowNode this_ |
-      this.getName() = store.getName() and
+      store_.getNode() = store and this_.getNode() = this
-      this.getScope() = store.getScope()
     |
-      store.getAFlowNode().strictlyDominates(this.getAFlowNode())
+      this.getName() = store.getName() and
+      this.getScope() = store.getScope() and
+      store_.strictlyDominates(this_)
     )
   }
 }

python/ql/lib/semmle/python/dataflow/new/BarrierGuards.qll

@@ -5,24 +5,30 @@ private import semmle.python.dataflow.new.DataFlow
 
 private predicate constCompare(DataFlow::GuardNode g, ControlFlowNode node, boolean branch) {
   exists(CompareNode cn | cn = g |
-    exists(ImmutableLiteral const, Cmpop op |
+    exists(ImmutableLiteral const, Cmpop op, ControlFlowNode c |
-      op = any(Eq eq) and branch = true
+      c.getNode() = const and
-      or
+      (
-      op = any(NotEq ne) and branch = false
+        op = any(Eq eq) and branch = true
+        or
+        op = any(NotEq ne) and branch = false
+      )
     |
-      cn.operands(const.getAFlowNode(), op, node)
+      cn.operands(c, op, node)
       or
-      cn.operands(node, op, const.getAFlowNode())
+      cn.operands(node, op, c)
     )
     or
-    exists(NameConstant const, Cmpop op |
+    exists(NameConstant const, Cmpop op, ControlFlowNode c |
-      op = any(Is is_) and branch = true
+      c.getNode() = const and
-      or
+      (
-      op = any(IsNot isn) and branch = false
+        op = any(Is is_) and branch = true
+        or
+        op = any(IsNot isn) and branch = false
+      )
     |
-      cn.operands(const.getAFlowNode(), op, node)
+      cn.operands(c, op, node)
       or
-      cn.operands(node, op, const.getAFlowNode())
+      cn.operands(node, op, c)
     )
     or
     exists(IterableNode const_iterable, Cmpop op |

python/ql/lib/semmle/python/dataflow/new/internal/Attributes.qll

@@ -228,7 +228,7 @@ private class ClassDefinitionAsAttrWrite extends AttrWrite, CfgNode {
 
   override Node getValue() { result.asCfgNode() = node.getValue() }
 
-  override Node getObject() { result.asCfgNode() = cls.getAFlowNode() }
+  override Node getObject() { result.asCfgNode().getNode() = cls }
 
   override ExprNode getAttributeNameExpr() { none() }
 

python/ql/lib/semmle/python/dataflow/new/internal/DataFlowDispatch.qll

@@ -1913,8 +1913,8 @@ abstract class ReturnNode extends Node {
 class ExtractedReturnNode extends ReturnNode, CfgNode {
   // See `TaintTrackingImplementation::returnFlowStep`
   ExtractedReturnNode() {
-    node = any(Return ret).getValue().getAFlowNode() or
+    node.getNode() = any(Return ret).getValue() or
-    node = any(Yield yield).getAFlowNode()
+    node.getNode() = any(Yield yield)
   }
 
   override ReturnKind getKind() { any() }
@@ -1932,7 +1932,7 @@ class ExtractedReturnNode extends ReturnNode, CfgNode {
 class YieldNodeInContextManagerFunction extends ReturnNode, CfgNode {
   YieldNodeInContextManagerFunction() {
     hasContextmanagerDecorator(node.getScope()) and
-    node = any(Yield yield).getValue().getAFlowNode()
+    node.getNode() = any(Yield yield).getValue()
   }
 
   override ReturnKind getKind() { any() }

python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPrivate.qll

@@ -185,8 +185,8 @@ private predicate synthDictSplatArgumentNodeStoreStep(
  */
 predicate yieldStoreStep(Node nodeFrom, Content c, Node nodeTo) {
   exists(Yield yield |
-    nodeTo.asCfgNode() = yield.getAFlowNode() and
+    nodeTo.asCfgNode().getNode() = yield and
-    nodeFrom.asCfgNode() = yield.getValue().getAFlowNode() and
+    nodeFrom.asCfgNode().getNode() = yield.getValue() and
     // TODO: Consider if this will also need to transfer dictionary content
     // once dictionary comprehensions are supported.
     c instanceof ListElementContent

python/ql/lib/semmle/python/dataflow/new/internal/DataFlowPublic.qll

@@ -485,7 +485,7 @@ class ModuleVariableNode extends Node, TModuleVariableNode {
 
   /** Gets a node that reads this variable, excluding reads that happen through `from ... import *`. */
   Node getALocalRead() {
-    result.asCfgNode() = var.getALoad().getAFlowNode() and
+    result.asCfgNode().getNode() = var.getALoad() and
     not result.getScope() = mod
   }
 

python/ql/lib/semmle/python/dataflow/new/internal/ImportResolution.qll

@@ -9,7 +9,19 @@ private import semmle.python.dataflow.new.DataFlow
 private import semmle.python.dataflow.new.internal.ImportStar
 private import semmle.python.dataflow.new.TypeTracking
 private import semmle.python.dataflow.new.internal.DataFlowPrivate
-private import semmle.python.essa.SsaDefinitions
+
+/**
+ * Holds if `init` is a package's `__init__.py` and `var` is a global variable in
+ * `init` whose name matches a submodule of the package.
+ *
+ * Inlined from `SsaSource::init_module_submodule_defn` to avoid pulling
+ * `semmle.python.essa.SsaDefinitions` into the new dataflow stack.
+ */
+private predicate initModuleSubmoduleDefn(GlobalVariable var, Module init) {
+  init.isPackageInit() and
+  exists(init.getPackage().getSubModule(var.getId())) and
+  var.getScope() = init
+}
 
 /**
  * Python modules and the way imports are resolved are... complicated. Here's a crash course in how
@@ -326,7 +338,7 @@ module ImportResolution {
     // imported yet.
     exists(string submodule, Module package, EssaVariable var |
       submodule = var.getName() and
-      SsaSource::init_module_submodule_defn(var.getSourceVariable(), package.getEntryNode()) and
+      initModuleSubmoduleDefn(var.getSourceVariable(), package) and
       m = getModuleFromName(package.getPackageName() + "." + submodule) and
       result.asCfgNode() = var.getDefinition().(EssaNodeDefinition).getDefiningNode()
     )

python/ql/lib/semmle/python/dataflow/new/internal/SsaImpl.qll

@@ -0,0 +1,547 @@
+/**
+ * Provides the Python SSA implementation built on the new (shared) CFG.
+ *
+ * Mirrors the Java SSA adapter at
+ * `java/ql/lib/semmle/code/java/dataflow/internal/SsaImpl.qll`:
+ * an `InputSig` is defined in terms of positional `(BasicBlock, int)`
+ * variable references, and the shared
+ * `codeql.ssa.Ssa::Make<Location, Cfg, Input>` module is then
+ * instantiated.
+ *
+ * `SourceVariable` is the AST-level `Py::Variable`. Variable references
+ * are looked up via the CFG facade's `NameNode.defines`/`uses`/`deletes`
+ * predicates, which themselves are one-line bridges to AST-level
+ * `Name.defines`/`uses`/`deletes`.
+ *
+ * Implicit-entry definitions are inserted for:
+ *   - non-local / global / builtin variables that are read in the scope
+ *     but never assigned (no enclosing CFG node defines them),
+ *   - captured variables (variables defined in an enclosing scope that
+ *     are read inside the scope), and
+ *   - parameters, but only if the corresponding parameter name is *not*
+ *     itself a CFG node. With the C#-style parameter wiring already
+ *     installed in `AstNodeImpl.qll`, parameter names *are* CFG nodes,
+ *     so the regular `variableWrite` path handles them — no `i = -1`
+ *     entry is needed for ordinary parameters.
+ */
+overlay[local?]
+module;
+
+private import python as Py
+private import semmle.python.controlflow.internal.AstNodeImpl as CfgImpl
+private import semmle.python.controlflow.internal.Cfg as Cfg
+private import codeql.ssa.Ssa as SsaImplCommon
+private import codeql.controlflow.BasicBlock as BB
+
+/**
+ * Adapts the Python `Cfg` facade to the shared SSA library's `CfgSig`.
+ * All members are inherited from `Cfg::ControlFlowNode` and
+ * `Cfg::BasicBlock`.
+ */
+private module CfgForSsa implements BB::CfgSig<Py::Location> {
+  class ControlFlowNode = CfgImpl::ControlFlowNode;
+
+  class BasicBlock = CfgImpl::BasicBlock;
+
+  class EntryBasicBlock = CfgImpl::Cfg::EntryBasicBlock;
+
+  predicate dominatingEdge = CfgImpl::Cfg::dominatingEdge/2;
+}
+
+/**
+ * A source variable for SSA, wrapping a Python AST `Variable`.
+ *
+ * We only track variables that are read at least once in their scope —
+ * tracking write-only variables would be unnecessary work — *except*
+ * for module-scope globals, where the "read" can be external (e.g.
+ * `import mymodule; mymodule.x`). Such globals are tracked
+ * unconditionally so that import-resolution can find their defining
+ * write.
+ */
+private newtype TSsaSourceVariable =
+  TPyVar(Py::Variable v) {
+    // Has a use somewhere — read-relevant for SSA.
+    exists(Cfg::NameNode n | n.uses(v))
+    or
+    // Or has a deletion (treated as a write that destroys the value).
+    exists(Cfg::NameNode n | n.deletes(v))
+    or
+    // Or is a module-scope global written in this module — must be
+    // tracked even if never read locally, because importers may read
+    // it as an attribute on the module object.
+    v.getScope() instanceof Py::Module and
+    exists(Cfg::NameNode n | n.defines(v))
+    or
+    // Or is a parameter — parameters must always have a
+    // `ParameterDefinition` for dataflow argument-routing to work,
+    // even if the parameter is never read in its scope. Mirrors
+    // legacy ESSA's `ParameterDefinition` (which fired for every
+    // parameter binding regardless of liveness).
+    exists(Py::Parameter p | p.asName() = v.getAStore())
+  }
+
+/**
+ * A source variable for SSA, wrapping a Python AST `Variable`.
+ */
+class SsaSourceVariable extends TSsaSourceVariable {
+  /** Gets the underlying Python AST variable. */
+  Py::Variable getVariable() { this = TPyVar(result) }
+
+  /** Gets the (textual) name of this variable. */
+  string getName() { result = this.getVariable().getId() }
+
+  /** Gets a textual representation of this source variable. */
+  string toString() { result = this.getVariable().toString() }
+
+  /** Gets the location of this source variable. */
+  Py::Location getLocation() { result = this.getVariable().getScope().getLocation() }
+
+  /** Gets the scope in which this variable lives. */
+  Py::Scope getScope() { result = this.getVariable().getScope() }
+
+  /**
+   * Gets a use of this variable as it appears in the source — a `NameNode`
+   * that loads or deletes the variable. Mirrors legacy
+   * `SsaSourceVariable.getASourceUse()`.
+   */
+  Cfg::ControlFlowNode getASourceUse() {
+    exists(Cfg::NameNode n | result = n |
+      n.uses(this.getVariable()) or n.deletes(this.getVariable())
+    )
+  }
+
+  /**
+   * Gets an implicit use of this variable. The new SSA does not have
+   * implicit-use refinements, but we keep this for API parity — every
+   * normal-exit of the variable's scope counts as a sink, ensuring
+   * variables stay live to scope exit for taint-tracking.
+   */
+  Cfg::ControlFlowNode getAnImplicitUse() {
+    result.isNormalExit() and result.getScope() = this.getScope()
+  }
+
+  /**
+   * Gets a use of this variable — either an explicit source use or an
+   * implicit use at scope exit. Mirrors legacy `SsaSourceVariable.getAUse()`.
+   */
+  Cfg::ControlFlowNode getAUse() {
+    result = this.getASourceUse() or result = this.getAnImplicitUse()
+  }
+}
+
+/**
+ * Holds if `v` is a non-local read in scope `s`, in the sense that `s`
+ * uses `v` but does not write it within `s`. This includes globals,
+ * builtins, and variables captured from an enclosing function scope.
+ *
+ * The `Py::Variable` `v` lives in some defining scope (the module for
+ * globals, an outer function for closures, etc.); the reading scope
+ * `s` is the scope where the use of `v` occurs.
+ */
+private predicate nonLocalReadIn(Py::Variable v, Py::Scope s) {
+  exists(Cfg::NameNode n |
+    n.uses(v) and
+    n.getScope() = s and
+    not exists(Cfg::NameNode def | def.defines(v) and def.getScope() = s)
+  ) and
+  // Match legacy ESSA: only create entry defs for variables that have
+  // at least one defining store somewhere — otherwise the entry def
+  // represents "nothing reaches here", which is the default anyway and
+  // introduces no useful flow. (Legacy's `ModuleVariable` required a
+  // store; this is the closure-aware generalisation.)
+  exists(Cfg::NameNode store | store.defines(v))
+}
+
+/**
+ * Holds if `bb` is the entry basic block of a scope where `v` should
+ * have an implicit entry definition. This covers:
+ *   - non-local / global / builtin variables read in `s`, and
+ *   - captured variables (defined in an enclosing scope but read in `s`).
+ *
+ * Each reading scope gets its own entry def, so a closure variable can
+ * have multiple entry defs across all functions/methods that read it.
+ *
+ * Parameters are *not* included: their bound `Name` is itself a CFG
+ * node (per the C#-style parameter wiring), so `variableWrite` fires at
+ * the parameter's natural CFG index.
+ */
+private predicate hasEntryDefIn(SsaSourceVariable v, CfgImpl::BasicBlock bb) {
+  exists(Py::Scope s |
+    nonLocalReadIn(v.getVariable(), s) and
+    bb = entryBlock(s)
+  )
+}
+
+/**
+ * Gets the entry basic block of scope `s`, where implicit entry
+ * definitions are placed (at synthetic index `-1`).
+ */
+private CfgImpl::BasicBlock entryBlock(Py::Scope s) {
+  exists(CfgImpl::ControlFlowNode entry |
+    entry instanceof CfgImpl::ControlFlow::EntryNode and
+    entry.getEnclosingCallable().asScope() = s and
+    result = entry.getBasicBlock()
+  )
+}
+
+/**
+ * The SSA `InputSig` for Python. References are positional
+ * `(BasicBlock, int)` pairs into the new CFG.
+ */
+private module SsaImplInput implements SsaImplCommon::InputSig<Py::Location, CfgImpl::BasicBlock> {
+  class SourceVariable = SsaSourceVariable;
+
+  predicate variableWrite(CfgImpl::BasicBlock bb, int i, SourceVariable v, boolean certain) {
+    // Explicit binding at a CFG node — includes assignments,
+    // parameter Names (wired in via the C# pattern), exception-handler
+    // `as`-bindings, import aliases, and match-pattern captures.
+    exists(Cfg::NameNode n |
+      bb.getNode(i) = n and
+      n.defines(v.getVariable()) and
+      certain = true
+    )
+    or
+    // `del x` — removes the binding. Modelled as a certain write that
+    // makes any subsequent read invalid.
+    exists(Cfg::NameNode n |
+      bb.getNode(i) = n and
+      n.deletes(v.getVariable()) and
+      certain = true
+    )
+    or
+    // Implicit entry definition for non-local / captured / global /
+    // builtin variables read in some scope. Each reading scope's entry
+    // block gets one such write, allowing closures: e.g. when `x` is a
+    // parameter of an outer function and read inside a nested
+    // function, both scopes get entry defs for `x`.
+    hasEntryDefIn(v, bb) and
+    i = -1 and
+    certain = true
+    or
+    // `from X import *` — possibly rebinds every name in the importing
+    // scope. Modelled as an uncertain write at the import-star's CFG
+    // position for every variable that lives in (or is referenced
+    // from) the same scope as the import-star. Mirrors legacy ESSA's
+    // `ImportStarRefinement` (see `essa/SsaDefinitions.qll`'s
+    // `import_star_refinement` predicate). The write is uncertain so
+    // that prior definitions of the variable remain available — the
+    // shared-SSA `SsaUncertainWrite` merges the new value with the
+    // immediately preceding definition.
+    exists(Cfg::ImportStarNode imp |
+      bb.getNode(i) = imp and
+      certain = false and
+      (
+        v.getVariable().getScope() = imp.getScope()
+        or
+        // Variable is defined in some other scope but referenced in
+        // the same scope as the import-star (matches legacy clause 2:
+        // `other.uses(v) and def.getScope() = other.getScope()`).
+        exists(Cfg::NameNode other |
+          other.uses(v.getVariable()) and
+          imp.getScope() = other.getScope()
+        )
+      )
+    )
+  }
+
+  predicate variableRead(CfgImpl::BasicBlock bb, int i, SourceVariable v, boolean certain) {
+    // Explicit source use — a `Name` load or a `del x` of the variable.
+    exists(Cfg::NameNode n |
+      bb.getNode(i) = n and
+      n.uses(v.getVariable()) and
+      certain = true
+    )
+    or
+    // Synthetic use at the normal exit of the variable's defining scope.
+    // This keeps every variable live to scope exit so that callers (e.g.
+    // `module_export` in ImportResolution.qll, or taint-tracking pass-through
+    // through unread locals) can ask "which definition reaches end of
+    // scope?". Mirrors legacy ESSA's `SsaSourceVariable.getAUse()` which
+    // included `getScope().getANormalExit()`.
+    exists(Cfg::ControlFlowNode exit |
+      exit.isNormalExit() and
+      exit.getScope() = v.getVariable().getScope() and
+      bb.getNode(i) = exit and
+      certain = true
+    )
+  }
+}
+
+/**
+ * The shared SSA instantiation for Python.
+ *
+ * Members:
+ *   - `Definition` — the union of explicit, uncertain, and phi definitions
+ *   - `WriteDefinition`, `UncertainWriteDefinition`, `PhiNode`
+ *   - the standard SSA predicates (`getAUse`, `getAnUltimateDefinition`, ...).
+ */
+module Ssa = SsaImplCommon::Make<Py::Location, CfgForSsa, SsaImplInput>;
+
+final class Definition = Ssa::Definition;
+
+final class WriteDefinition = Ssa::WriteDefinition;
+
+final class UncertainWriteDefinition = Ssa::UncertainWriteDefinition;
+
+final class PhiNode = Ssa::PhiNode;
+
+// ===========================================================================
+// ESSA-shaped adapter layer
+//
+// The dataflow library (`python/ql/lib/semmle/python/dataflow/new/`) and
+// related modules (`ApiGraphs.qll`, etc.) consume the legacy ESSA API
+// (`EssaVariable`, `EssaDefinition`, `AssignmentDefinition`,
+// `ScopeEntryDefinition`, `ParameterDefinition`, `WithDefinition`,
+// `PhiFunction`, plus the `AdjacentUses` module). To migrate them off
+// the legacy CFG, we expose the same API surface on top of the
+// shared SSA built above.
+//
+// This adapter is intentionally narrow: it covers only the predicates
+// that new dataflow consumes. The richer legacy ESSA — refinement
+// nodes, attribute refinements, edge refinements — stays available
+// via `semmle.python.essa.Essa` for points-to / legacy code.
+// ===========================================================================
+/**
+ * Gets the CFG node at which a write definition's binding takes place.
+ *
+ * For ordinary writes (assignment, deletion, parameter) this is the
+ * canonical CFG node of the bound Name. For implicit entry definitions
+ * (synthesised at position `-1` of a scope's entry BB) this is the
+ * scope's entry node.
+ */
+private Cfg::ControlFlowNode writeDefNode(Ssa::WriteDefinition def) {
+  exists(CfgImpl::BasicBlock bb, int i | def.definesAt(_, bb, i) |
+    i >= 0 and result = bb.getNode(i)
+    or
+    i = -1 and result = bb.getNode(0)
+  )
+}
+
+/**
+ * A write definition whose binding has a corresponding CFG node — i.e.
+ * everything that's not a phi node. Mirrors legacy ESSA's
+ * `EssaNodeDefinition`.
+ */
+class EssaNodeDefinition extends Ssa::WriteDefinition {
+  /** Gets the CFG node where this definition's binding takes place. */
+  Cfg::ControlFlowNode getDefiningNode() { result = writeDefNode(this) }
+
+  /** Gets the variable defined here (legacy name). */
+  SsaSourceVariable getVariable() { result = this.getSourceVariable() }
+
+  /** Gets the enclosing scope. */
+  Py::Scope getScope() {
+    exists(Cfg::ControlFlowNode n | n = this.getDefiningNode() | result = n.getScope())
+  }
+
+  /**
+   * Holds if this definition defines source variable `v` at CFG node
+   * `defNode`. Flatter form of `getSourceVariable()` +
+   * `getDefiningNode()`, matching legacy ESSA's `definedBy`.
+   */
+  predicate definedBy(SsaSourceVariable v, Cfg::ControlFlowNode defNode) {
+    v = this.getSourceVariable() and defNode = this.getDefiningNode()
+  }
+}
+
+/**
+ * An assignment definition: any binding where the value being assigned
+ * is statically known via `Cfg::DefinitionNode.getValue()`. Includes
+ * plain assignments, walrus, annotated assignments, augmented
+ * assignments, import aliases (`import x` / `from m import x [as y]`),
+ * `with ... as x`, and for-target bindings (where `getValue()` returns
+ * the iter expression's CFG node). Excludes parameter bindings —
+ * those are modelled by `ParameterDefinition`.
+ */
+class AssignmentDefinition extends EssaNodeDefinition {
+  AssignmentDefinition() {
+    exists(Cfg::NameNode n | n = this.getDefiningNode() |
+      exists(n.(Cfg::DefinitionNode).getValue()) and
+      not n.(Cfg::ControlFlowNode).isParameter()
+    )
+  }
+
+  /** Gets the CFG node for the value being assigned, if statically known. */
+  Cfg::ControlFlowNode getValue() {
+    result = this.getDefiningNode().(Cfg::DefinitionNode).getValue()
+  }
+}
+
+/**
+ * A parameter definition — the binding of a parameter name in a
+ * function's scope.
+ */
+class ParameterDefinition extends EssaNodeDefinition {
+  ParameterDefinition() { this.getDefiningNode().isParameter() }
+
+  /** Gets the AST `Parameter` (a `Py::Name` in param context). */
+  Py::Name getParameter() { result = this.getDefiningNode().getNode() }
+}
+
+/**
+ * A definition introduced by a `with ... as x:` clause.
+ */
+class WithDefinition extends EssaNodeDefinition {
+  WithDefinition() {
+    exists(Cfg::NameNode n, Py::With w |
+      n = this.getDefiningNode() and
+      w.getOptionalVars() = n.getNode()
+    )
+  }
+}
+
+/**
+ * An assignment where the LHS is a tuple/list and the RHS is unpacked:
+ * `a, b = (1, 2)` or `a, *rest = xs`. The SSA def lives at the inner
+ * `Name` CFG node, but for IterableUnpacking integration we expose
+ * the enclosing `StarredNode` as the `getDefiningNode()` for `*rest`
+ * patterns — mirroring legacy ESSA's `multi_assignment_definition`,
+ * which placed the def at the StarredNode CFG node.
+ */
+class MultiAssignmentDefinition extends EssaNodeDefinition {
+  MultiAssignmentDefinition() {
+    exists(Cfg::NameNode n | n = super.getDefiningNode() |
+      exists(Py::Assign a, Py::Expr lhs |
+        a.getATarget() = lhs and
+        (lhs instanceof Py::Tuple or lhs instanceof Py::List) and
+        lhs.getASubExpression+() = n.getNode()
+      )
+      or
+      // For-loop with tuple/list target: `for a, b in xs:` —
+      // tuple-unpacking semantics applies to the for-target.
+      exists(Py::For f, Py::Expr lhs |
+        f.getTarget() = lhs and
+        (lhs instanceof Py::Tuple or lhs instanceof Py::List) and
+        lhs.getASubExpression+() = n.getNode()
+      )
+    )
+  }
+
+  override Cfg::ControlFlowNode getDefiningNode() {
+    // Default: the underlying `Name` CFG node (where the SSA def lives).
+    not exists(Cfg::StarredNode s |
+      s.getNode().(Py::Starred).getValue() = super.getDefiningNode().getNode()
+    ) and
+    result = super.getDefiningNode()
+    or
+    // Exception: for `*rest`, expose the enclosing `Starred` CFG node
+    // so that `IterableUnpacking::iterableUnpackingStarredElementStoreStep`
+    // can attach the rest-list to it.
+    exists(Cfg::StarredNode s |
+      s.getNode().(Py::Starred).getValue() = super.getDefiningNode().getNode()
+    |
+      result = s
+    )
+  }
+}
+
+/**
+ * An implicit entry definition for a non-local / captured / global /
+ * builtin variable read in a scope but not defined there.
+ *
+ * Inherits from `EssaNodeDefinition` and exposes the scope's entry node
+ * as its defining node (matching legacy ESSA semantics).
+ */
+class ScopeEntryDefinition extends EssaNodeDefinition {
+  ScopeEntryDefinition() {
+    exists(CfgImpl::BasicBlock bb |
+      this.definesAt(_, bb, -1) and
+      bb instanceof CfgImpl::Cfg::EntryBasicBlock
+    )
+  }
+
+  /** Gets the enclosing scope (the scope whose entry block this def is in). */
+  override Py::Scope getScope() {
+    exists(CfgImpl::BasicBlock bb |
+      this.definesAt(_, bb, -1) and
+      result = bb.getNode(0).(Cfg::ControlFlowNode).getScope()
+    )
+  }
+}
+
+/** A phi node (alias matching legacy naming). */
+class PhiFunction extends PhiNode {
+  /**
+   * Gets an input to this phi function (a definition that flows into
+   * the phi from one of its predecessor blocks). Mirrors legacy
+   * ESSA's `PhiFunction.getAnInput()`.
+   */
+  Ssa::Definition getAnInput() { Ssa::phiHasInputFromBlock(this, result, _) }
+}
+
+/** Base class for all ESSA definitions (legacy-shaped). */
+class EssaDefinition = Ssa::Definition;
+
+/**
+ * An adapter representing a single SSA-defined "variable" — wrapping
+ * one `Ssa::Definition`. Mirrors legacy `EssaVariable` API.
+ */
+class EssaVariable extends Ssa::Definition {
+  /** Gets the underlying SSA definition (legacy name). */
+  Ssa::Definition getDefinition() { result = this }
+
+  /**
+   * Gets a CFG node where this definition is used. Includes regular
+   * `Name` reads as well as the synthetic scope-exit "use" registered
+   * via `SsaImplInput::variableRead` — mirrors legacy ESSA's
+   * `EssaVariable.getAUse()` which inherited the synthetic exit-use
+   * from `SsaSourceVariable`.
+   */
+  Cfg::ControlFlowNode getAUse() {
+    exists(CfgImpl::BasicBlock bb, int i |
+      Ssa::ssaDefReachesRead(this.getSourceVariable(), this, bb, i) and
+      bb.getNode(i) = result
+    )
+  }
+
+  /** Gets the (textual) name of the underlying variable. */
+  string getName() { result = this.getSourceVariable().getVariable().getId() }
+
+  /** Gets the scope in which this variable lives. */
+  Py::Scope getScope() { result = this.getSourceVariable().getVariable().getScope() }
+
+  /** Gets an ultimate non-phi ancestor of this definition. */
+  EssaVariable getAnUltimateDefinition() {
+    if this instanceof PhiNode
+    then
+      exists(Ssa::Definition input |
+        Ssa::phiHasInputFromBlock(this, input, _) and
+        result = input.(EssaVariable).getAnUltimateDefinition()
+      )
+    else result = this
+  }
+}
+
+/**
+ * Adjacent use-use and def-use relations exposed by the shared SSA
+ * library. Provides the same interface as legacy
+ * `semmle.python.essa.SsaCompute::AdjacentUses`.
+ */
+module AdjacentUses {
+  /** Holds if `nodeFrom` and `nodeTo` are adjacent uses of the same SSA variable. */
+  predicate adjacentUseUse(Cfg::NameNode nodeFrom, Cfg::NameNode nodeTo) {
+    exists(SsaSourceVariable v, CfgImpl::BasicBlock bb1, int i1, CfgImpl::BasicBlock bb2, int i2 |
+      Ssa::adjacentUseUse(bb1, i1, bb2, i2, v, _) and
+      nodeFrom = bb1.getNode(i1) and
+      nodeTo = bb2.getNode(i2)
+    )
+  }
+
+  /** Holds if `use` is a first use of definition `def`. */
+  predicate firstUse(Ssa::Definition def, Cfg::NameNode use) {
+    exists(CfgImpl::BasicBlock bb, int i |
+      Ssa::firstUse(def, bb, i, _) and
+      use = bb.getNode(i)
+    )
+  }
+
+  /**
+   * Holds if `use` is any reachable use of definition `def`. Combines
+   * `firstUse` with transitive use-use adjacency.
+   */
+  predicate useOfDef(Ssa::Definition def, Cfg::NameNode use) {
+    firstUse(def, use)
+    or
+    exists(Cfg::NameNode mid | useOfDef(def, mid) and adjacentUseUse(mid, use))
+  }
+}

python/ql/lib/semmle/python/dataflow/new/internal/TypeTrackingImpl.qll

@@ -94,8 +94,10 @@ private module SummaryTypeTrackerInput implements SummaryTypeTracker::Input {
   Node returnOf(Node callable, SummaryComponent return) {
     return = FlowSummaryImpl::Private::SummaryComponent::return() and
     // `result` should be the return value of a callable expression (lambda or function) referenced by `callable`
-    result.asCfgNode() =
+    exists(Return ret |
-      callable.getALocalSource().asExpr().(CallableExpr).getInnerScope().getAReturnValueFlowNode()
+      ret.getScope() = callable.getALocalSource().asExpr().(CallableExpr).getInnerScope() and
+      result.asCfgNode().getNode() = ret.getValue()
+    )
   }
 
   // Relating callables to nodes

python/ql/lib/semmle/python/dataflow/new/internal/VariableCapture.qll

@@ -61,7 +61,7 @@ private module CaptureInput implements Shared::InputSig<Location, Cfg::BasicBloc
   class VariableWrite extends ControlFlowNode {
     CapturedVariable v;
 
-    VariableWrite() { this = v.getAStore().getAFlowNode().(DefinitionNode).getValue() }
+    VariableWrite() { exists(DefinitionNode d | d.getNode() = v.getAStore() | this = d.getValue()) }
 
     CapturedVariable getVariable() { result = v }
 
@@ -71,7 +71,7 @@ private module CaptureInput implements Shared::InputSig<Location, Cfg::BasicBloc
   class VariableRead extends Expr {
     CapturedVariable v;
 
-    VariableRead() { this = v.getALoad().getAFlowNode() }
+    VariableRead() { this.getNode() = v.getALoad() }
 
     CapturedVariable getVariable() { result = v }
   }

python/ql/lib/semmle/python/dataflow/old/Implementation.qll

@@ -448,8 +448,7 @@ class TaintTrackingImplementation extends string instanceof TaintTracking::Confi
       context = TNoParam() and
       src = TTaintTrackingNode_(retval, TNoParam(), path, kind, this) and
       node.asCfgNode() = call and
-      retval.asCfgNode() =
+      retval.asCfgNode().getNode() = any(Return ret | ret.getScope() = pyfunc.getScope()).getValue()
-        any(Return ret | ret.getScope() = pyfunc.getScope()).getValue().getAFlowNode()
     ) and
     edgeLabel = "return"
   }
@@ -471,8 +470,7 @@ class TaintTrackingImplementation extends string instanceof TaintTracking::Confi
       this.callContexts(call, src, pyfunc, context, callee) and
       retnode = TTaintTrackingNode_(retval, callee, path, kind, this) and
       node.asCfgNode() = call and
-      retval.asCfgNode() =
+      retval.asCfgNode().getNode() = any(Return ret | ret.getScope() = pyfunc.getScope()).getValue()
-        any(Return ret | ret.getScope() = pyfunc.getScope()).getValue().getAFlowNode()
     ) and
     edgeLabel = "call"
   }
@@ -716,8 +714,10 @@ private class EssaTaintTracking extends string instanceof TaintTracking::Configu
       src = TTaintTrackingNode_(srcnode, context, path, srckind, this) and
       path.noAttribute()
     |
-      assign.getValue().getAFlowNode() = srcnode.asCfgNode() and
+      srcnode.asCfgNode().getNode() = assign.getValue() and
-      depth = iterable_unpacking_descent(assign.getATarget().getAFlowNode(), defn.getDefiningNode()) and
+      exists(SequenceNode left_parent | left_parent.getNode() = assign.getATarget() |
+        depth = iterable_unpacking_descent(left_parent, defn.getDefiningNode())
+      ) and
       kind = taint_at_depth(srckind, depth)
     )
   }
@@ -964,7 +964,7 @@ private TaintKind taint_at_depth(SequenceKind parent_kind, int depth) {
  * - with `left_defn` = `*y`, `left_parent` = `((x, *y), ...)`, result = 1
  */
 int iterable_unpacking_descent(SequenceNode left_parent, ControlFlowNode left_defn) {
-  exists(Assign a | a.getATarget().getASubExpression*().getAFlowNode() = left_parent) and
+  exists(Assign a | left_parent.getNode() = a.getATarget().getASubExpression*()) and
   left_parent.getAnElement() = left_defn and
   // Handle `a, *b = some_iterable`
   if left_defn instanceof StarredNode then result = 0 else result = 1

python/ql/lib/semmle/python/essa/SsaDefinitions.qll

@@ -56,7 +56,7 @@ module SsaSource {
   predicate with_definition(Variable v, ControlFlowNode defn) {
     exists(With with, Name var |
       with.getOptionalVars() = var and
-      var.getAFlowNode() = defn
+      defn.getNode() = var
     |
       var = v.getAStore()
     )
@@ -67,7 +67,7 @@ module SsaSource {
   predicate pattern_capture_definition(Variable v, ControlFlowNode defn) {
     exists(MatchCapturePattern capture, Name var |
       capture.getVariable() = var and
-      var.getAFlowNode() = defn
+      defn.getNode() = var
     |
       var = v.getAStore()
     )
@@ -78,7 +78,7 @@ module SsaSource {
   predicate pattern_alias_definition(Variable v, ControlFlowNode defn) {
     exists(MatchAsPattern pattern, Name var |
       pattern.getAlias() = var and
-      var.getAFlowNode() = defn
+      defn.getNode() = var
     |
       var = v.getAStore()
     )

python/ql/lib/semmle/python/frameworks/Bottle.qll

@@ -59,7 +59,7 @@ module Bottle {
 
         override Parameter getARoutedParameter() { none() }
 
-        override Function getARequestHandler() { result.getADecorator().getAFlowNode() = node }
+        override Function getARequestHandler() { node.getNode() = result.getADecorator() }
       }
     }
 
@@ -73,7 +73,10 @@ module Bottle {
       /** A response returned by a view callable. */
       class BottleReturnResponse extends Http::Server::HttpResponse::Range {
         BottleReturnResponse() {
-          this.asCfgNode() = any(View::ViewCallable vc).getAReturnValueFlowNode()
+          exists(Return ret |
+            ret.getScope() = any(View::ViewCallable vc) and
+            this.asCfgNode().getNode() = ret.getValue()
+          )
         }
 
         override DataFlow::Node getBody() { result = this }

python/ql/lib/semmle/python/frameworks/Django.qll

@@ -2872,7 +2872,10 @@ module PrivateDjango {
     DataFlow::CfgNode
   {
     DjangoRedirectViewGetRedirectUrlReturn() {
-      node = any(GetRedirectUrlFunction f).getAReturnValueFlowNode()
+      exists(Return ret |
+        ret.getScope() = any(GetRedirectUrlFunction f) and
+        node.getNode() = ret.getValue()
+      )
     }
 
     override DataFlow::Node getRedirectLocation() { result = this }

python/ql/lib/semmle/python/frameworks/FastApi.qll

@@ -129,7 +129,7 @@ module FastApi {
       result in [this.getArg(0), this.getArgByName("path")]
     }
 
-    override Function getARequestHandler() { result.getADecorator().getAFlowNode() = node }
+    override Function getARequestHandler() { node.getNode() = result.getADecorator() }
 
     override string getFramework() { result = "FastAPI" }
 
@@ -309,7 +309,10 @@ module FastApi {
       FastApiRouteSetup routeSetup;
 
       FastApiRequestHandlerReturn() {
-        node = routeSetup.getARequestHandler().getAReturnValueFlowNode()
+        exists(Return ret |
+          ret.getScope() = routeSetup.getARequestHandler() and
+          node.getNode() = ret.getValue()
+        )
       }
 
       override DataFlow::Node getBody() { result = this }

python/ql/lib/semmle/python/frameworks/Flask.qll

@@ -371,7 +371,7 @@ module Flask {
       result in [this.getArg(0), this.getArgByName("rule")]
     }
 
-    override Function getARequestHandler() { result.getADecorator().getAFlowNode() = node }
+    override Function getARequestHandler() { node.getNode() = result.getADecorator() }
   }
 
   /**
@@ -536,7 +536,7 @@ module Flask {
     FlaskRouteHandlerReturn() {
       exists(Function routeHandler |
         routeHandler = any(FlaskRouteSetup rs).getARequestHandler() and
-        node = routeHandler.getAReturnValueFlowNode() and
+        exists(Return ret | ret.getScope() = routeHandler and node.getNode() = ret.getValue()) and
         not this instanceof Flask::Response::InstanceSource
       )
     }

python/ql/lib/semmle/python/frameworks/FlaskAdmin.qll

@@ -38,7 +38,7 @@ private module FlaskAdmin {
       result in [this.getArg(0), this.getArgByName("url")]
     }
 
-    override Function getARequestHandler() { result.getADecorator().getAFlowNode() = node }
+    override Function getARequestHandler() { node.getNode() = result.getADecorator() }
   }
 
   /**
@@ -71,7 +71,7 @@ private module FlaskAdmin {
 
     override Function getARequestHandler() {
       exists(Flask::FlaskViewClass cls |
-        cls.getADecorator().getAFlowNode() = node and
+        node.getNode() = cls.getADecorator() and
         result = cls.getARequestHandler()
       )
     }

python/ql/lib/semmle/python/frameworks/Pyramid.qll

@@ -166,7 +166,10 @@ module Pyramid {
     /** A response returned by a view callable. */
     private class PyramidReturnResponse extends Http::Server::HttpResponse::Range {
       PyramidReturnResponse() {
-        this.asCfgNode() = any(View::ViewCallable vc).getAReturnValueFlowNode() and
+        exists(Return ret |
+          ret.getScope() = any(View::ViewCallable vc) and
+          this.asCfgNode().getNode() = ret.getValue()
+        ) and
         not this = instance()
       }
 

python/ql/lib/semmle/python/frameworks/Stdlib.qll

@@ -2254,8 +2254,9 @@ module StdlibPrivate {
       DataFlow::CfgNode
     {
       WsgirefSimpleServerApplicationReturn() {
-        exists(WsgirefSimpleServerApplication requestHandler |
+        exists(WsgirefSimpleServerApplication requestHandler, Return ret |
-          node = requestHandler.getAReturnValueFlowNode()
+          ret.getScope() = requestHandler and
+          node.getNode() = ret.getValue()
         )
       }
 

python/ql/lib/semmle/python/frameworks/Twisted.qll

@@ -182,7 +182,10 @@ private module Twisted {
     DataFlow::CfgNode
   {
     TwistedResourceRenderMethodReturn() {
-      this.asCfgNode() = any(TwistedResourceRenderMethod meth).getAReturnValueFlowNode()
+      exists(Return ret |
+        ret.getScope() = any(TwistedResourceRenderMethod meth) and
+        this.asCfgNode().getNode() = ret.getValue()
+      )
     }
 
     override DataFlow::Node getBody() { result = this }

python/ql/lib/semmle/python/internal/CachedStages.qll

@@ -77,7 +77,7 @@ module Stages {
       or
       exists(any(AstExtended::AstNode n).getParentNode())
       or
-      exists(any(AstExtended::AstNode n).getAFlowNode())
+      exists(PyFlow::ControlFlowNode cfg, AstExtended::AstNode n | cfg.getNode() = n)
       or
       exists(any(PyFlow::BasicBlock b).getImmediateDominator())
       or

python/ql/lib/semmle/python/objects/Callables.qll

@@ -56,8 +56,9 @@ abstract class CallableObjectInternal extends ObjectInternal {
 /** A Python function. */
 class PythonFunctionObjectInternal extends CallableObjectInternal, TPythonFunctionObject {
   override Function getScope() {
-    exists(CallableExpr expr |
+    exists(CallableExpr expr, ControlFlowNode exprCfg |
-      this = TPythonFunctionObject(expr.getAFlowNode()) and
+      exprCfg.getNode() = expr and
+      this = TPythonFunctionObject(exprCfg) and
       result = expr.getInnerScope()
     )
   }
@@ -80,11 +81,12 @@ class PythonFunctionObjectInternal extends CallableObjectInternal, TPythonFuncti
 
   pragma[nomagic]
   override predicate callResult(PointsToContext callee, ObjectInternal obj, CfgOrigin origin) {
-    exists(Function func, ControlFlowNode rval, ControlFlowNode forigin |
+    exists(Function func, Return ret, ControlFlowNode rval, ControlFlowNode forigin |
       func = this.getScope() and
       callee.appliesToScope(func)
     |
-      rval = func.getAReturnValueFlowNode() and
+      ret.getScope() = func and
+      rval.getNode() = ret.getValue() and
       PointsToInternal::pointsTo(rval, callee, obj, forigin) and
       origin = CfgOrigin::fromCfgNode(forigin)
     )
@@ -160,10 +162,11 @@ class PythonFunctionObjectInternal extends CallableObjectInternal, TPythonFuncti
 }
 
 private BasicBlock blockReturningNone(Function func) {
-  exists(Return ret |
+  exists(Return ret, ControlFlowNode ret_ |
     not exists(ret.getValue()) and
     ret.getScope() = func and
-    result = ret.getAFlowNode().getBasicBlock()
+    ret_.getNode() = ret and
+    result = ret_.getBasicBlock()
   )
 }
 

python/ql/lib/semmle/python/objects/Classes.qll

@@ -113,8 +113,9 @@ abstract class ClassObjectInternal extends ObjectInternal {
 class PythonClassObjectInternal extends ClassObjectInternal, TPythonClassObject {
   /** Gets the scope for this Python class */
   Class getScope() {
-    exists(ClassExpr expr |
+    exists(ClassExpr expr, ControlFlowNode exprCfg |
-      this = TPythonClassObject(expr.getAFlowNode()) and
+      exprCfg.getNode() = expr and
+      this = TPythonClassObject(exprCfg) and
       result = expr.getInnerScope()
     )
   }

python/ql/lib/semmle/python/objects/ObjectAPI.qll

@@ -745,7 +745,12 @@ class PythonFunctionValue extends FunctionValue {
   override int maxParameters() { result = this.getScope().getMaxPositionalArguments() }
 
   /** Gets a control flow node corresponding to a return statement in this function */
-  ControlFlowNode getAReturnedNode() { result = this.getScope().getAReturnValueFlowNode() }
+  ControlFlowNode getAReturnedNode() {
+    exists(Return ret |
+      ret.getScope() = this.getScope() and
+      result.getNode() = ret.getValue()
+    )
+  }
 
   override ClassValue getARaisedType() { scope_raises(result, this.getScope()) }
 

python/ql/lib/semmle/python/objects/TObject.qll

@@ -387,7 +387,7 @@ private PythonClassObjectInternal abcMetaClassObject() {
 private predicate neither_class_nor_static_method(Function f) {
   not exists(f.getADecorator())
   or
-  exists(ControlFlowNode deco | deco = f.getADecorator().getAFlowNode() |
+  exists(ControlFlowNode deco | deco.getNode() = f.getADecorator() |
     exists(ObjectInternal o | PointsToInternal::pointsTo(deco, _, o, _) |
       o != ObjectInternal::staticMethod() and
       o != ObjectInternal::classMethod()

python/ql/lib/semmle/python/pointsto/PointsTo.qll

@@ -711,7 +711,7 @@ private module InterModulePointsTo {
     ControlFlowNode f, PointsToContext context, ObjectInternal value, ControlFlowNode origin
   ) {
     exists(string name, ImportExpr i |
-      i.getAFlowNode() = f and
+      f.getNode() = i and
       i.getImportedModuleName() = name and
       PointsToInternal::module_imported_as(value, name) and
       origin = f and
@@ -2118,8 +2118,9 @@ module Types {
     result.getBuiltin() = cls.getBuiltin().getBaseClass() and n = 0
     or
     exists(Class pycls | pycls = cls.(PythonClassObjectInternal).getScope() |
-      exists(ObjectInternal base |
+      exists(ObjectInternal base, ControlFlowNode baseNode |
-        PointsToInternal::pointsTo(pycls.getBase(n).getAFlowNode(), _, base, _)
+        baseNode.getNode() = pycls.getBase(n) and
+        PointsToInternal::pointsTo(baseNode, _, base, _)
       |
         result = base and base != ObjectInternal::unknown()
         or
@@ -2223,7 +2224,10 @@ module Types {
   }
 
   private ControlFlowNode decorator_call_callee(PythonClassObjectInternal cls) {
-    result = cls.getScope().getADecorator().getAFlowNode().(CallNode).getFunction()
+    exists(CallNode deco |
+      deco.getNode() = cls.getScope().getADecorator() and
+      result = deco.getFunction()
+    )
   }
 
   private boolean has_six_add_metaclass(PythonClassObjectInternal cls) {
@@ -2262,7 +2266,7 @@ module Types {
   }
 
   private EssaVariable metaclass_var(Class cls) {
-    result.getASourceUse() = cls.getMetaClass().getAFlowNode()
+    result.getASourceUse().getNode() = cls.getMetaClass()
     or
     major_version() = 2 and
     not exists(cls.getMetaClass()) and

python/ql/lib/semmle/python/types/ClassObject.qll

@@ -181,7 +181,7 @@ class ClassObject extends Object {
     )
   }
 
-  ControlFlowNode declaredMetaClass() { result = this.getPyClass().getMetaClass().getAFlowNode() }
+  ControlFlowNode declaredMetaClass() { result.getNode() = this.getPyClass().getMetaClass() }
 
   /** Has type inference failed to compute the full class hierarchy for this class for the reason given. */
   predicate failedInference(string reason) { Types::failedInference(this.theClass(), reason) }
@@ -195,8 +195,9 @@ class ClassObject extends Object {
    * It is guaranteed that getProbableSingletonInstance() returns at most one Object for each ClassObject.
    */
   Object getProbableSingletonInstance() {
-    exists(ControlFlowNodeWithPointsTo use, Expr origin |
+    exists(ControlFlowNodeWithPointsTo use, Expr origin, ControlFlowNode origin_ |
-      use.refersTo(result, this, origin.getAFlowNode())
+      origin_.getNode() = origin and
+      use.refersTo(result, this, origin_)
     |
       this.hasStaticallyUniqueInstance() and
       /* Ensure that original expression will be executed only one. */

python/ql/lib/semmle/python/types/Exceptions.qll

@@ -427,7 +427,7 @@ class ExceptFlowNodeWithPointsTo extends ExceptFlowNode {
 }
 
 private ControlFlowNodeWithPointsTo element_from_tuple_objectapi(Object tuple) {
-  exists(Tuple t | t = tuple.getOrigin() and result = t.getAnElt().getAFlowNode())
+  exists(Tuple t | t = tuple.getOrigin() and result.getNode() = t.getAnElt())
 }
 
 /**

python/ql/lib/semmle/python/types/Extensions.qll

@@ -36,8 +36,8 @@ class RangeIterationVariableFact extends PointsToExtension {
   RangeIterationVariableFact() {
     exists(For f, ControlFlowNode iterable |
       iterable.getBasicBlock().dominates(this.(ControlFlowNode).getBasicBlock()) and
-      f.getIter().getAFlowNode() = iterable and
+      iterable.getNode() = f.getIter() and
-      f.getTarget().getAFlowNode() = this and
+      this.(ControlFlowNode).getNode() = f.getTarget() and
       exists(ObjectInternal range |
         PointsTo::pointsTo(iterable, _, range, _) and
         range.getClass() = ObjectInternal::builtin("range")

python/ql/lib/semmle/python/types/FunctionObject.qll

@@ -137,7 +137,10 @@ class PyFunctionObject extends FunctionObject {
 
   /** Gets a control flow node corresponding to the value of a return statement */
   ControlFlowNodeWithPointsTo getAReturnedNode() {
-    result = this.getFunction().getAReturnValueFlowNode()
+    exists(Return ret |
+      ret.getScope() = this.getFunction() and
+      result.getNode() = ret.getValue()
+    )
   }
 
   override string descriptiveString() {
@@ -170,7 +173,7 @@ class PyFunctionObject extends FunctionObject {
   predicate unconditionallyReturnsParameter(int n) {
     exists(SsaVariable pvar |
       exists(Parameter p | p = this.getFunction().getArg(n) |
-        p.asName().getAFlowNode() = pvar.getDefinition()
+        pvar.getDefinition().getNode() = p.asName()
       ) and
       exists(NameNode rval |
         rval = pvar.getAUse() and

python/ql/lib/semmle/python/types/Object.qll

@@ -337,7 +337,7 @@ class TupleObject extends SequenceObject {
     or
     this instanceof TupleNode
     or
-    exists(Function func | func.getVararg().getAFlowNode() = this)
+    exists(Function func | this.(ControlFlowNode).getNode() = func.getVararg())
   }
 }
 
@@ -352,7 +352,9 @@ module TupleObject {
 }
 
 class NonEmptyTupleObject extends TupleObject {
-  NonEmptyTupleObject() { exists(Function func | func.getVararg().getAFlowNode() = this) }
+  NonEmptyTupleObject() {
+    exists(Function func | this.(ControlFlowNode).getNode() = func.getVararg())
+  }
 
   override boolean booleanValue() { result = true }
 }

python/ql/src/Classes/ClassAttributes.qll

@@ -48,9 +48,11 @@ class CheckClass extends ClassObject {
         self_dict = sub.getObject()
         or
         /* Indirect assignment via temporary variable */
-        exists(SsaVariable v |
+        exists(SsaVariable v, ControlFlowNode subObjCfg, ControlFlowNode selfDictCfg |
-          v.getAUse() = sub.getObject().getAFlowNode() and
+          subObjCfg.getNode() = sub.getObject() and selfDictCfg.getNode() = self_dict
-          v.getDefinition().(DefinitionNode).getValue() = self_dict.getAFlowNode()
+        |
+          v.getAUse() = subObjCfg and
+          v.getDefinition().(DefinitionNode).getValue() = selfDictCfg
         )
       ) and
       a.getATarget() = sub and
@@ -62,9 +64,10 @@ class CheckClass extends ClassObject {
 
   pragma[nomagic]
   private predicate monkeyPatched(string name) {
-    exists(Attribute a |
+    exists(Attribute a, ControlFlowNode objCfg |
+      objCfg.getNode() = a.getObject() and
       a.getCtx() instanceof Store and
-      PointsTo::points_to(a.getObject().getAFlowNode(), _, this, _, _) and
+      PointsTo::points_to(objCfg, _, this, _, _) and
       a.getName() = name
     )
   }
@@ -84,9 +87,9 @@ class CheckClass extends ClassObject {
   }
 
   predicate interestingUndefined(SelfAttributeRead a) {
-    exists(string name | name = a.getName() |
+    exists(string name, ControlFlowNode aCfg | name = a.getName() and aCfg.getNode() = a |
       this.interestingContext(a, name) and
-      not this.definedInBlock(a.getAFlowNode().getBasicBlock(), name)
+      not this.definedInBlock(aCfg.getBasicBlock(), name)
     )
   }
 
@@ -109,8 +112,9 @@ class CheckClass extends ClassObject {
 
   pragma[nomagic]
   private predicate definitionInBlock(BasicBlock b, string name) {
-    exists(SelfAttributeStore sa |
+    exists(SelfAttributeStore sa, ControlFlowNode saCfg |
-      sa.getAFlowNode().getBasicBlock() = b and
+      saCfg.getNode() = sa and
+      saCfg.getBasicBlock() = b and
       sa.getName() = name and
       sa.getClass() = this.getPyClass()
     )

python/ql/src/Exceptions/CatchingBaseException.ql

@@ -15,7 +15,9 @@
 import python
 import semmle.python.ApiGraphs
 
-predicate doesnt_reraise(ExceptStmt ex) { ex.getAFlowNode().getBasicBlock().reachesExit() }
+predicate doesnt_reraise(ExceptStmt ex) {
+  exists(ControlFlowNode exCfg | exCfg.getNode() = ex | exCfg.getBasicBlock().reachesExit())
+}
 
 predicate catches_base_exception(ExceptStmt ex) {
   ex.getType() = API::builtin("BaseException").getAValueReachableFromSource().asExpr()

python/ql/src/Expressions/CallArgs.qll

@@ -116,7 +116,7 @@ FunctionValue get_function_or_initializer(Value func_or_cls) {
 predicate illegally_named_parameter_objectapi(Call call, Object func, string name) {
   not func.isC() and
   name = call.getANamedArgumentName() and
-  call.getAFlowNode() = get_a_call_objectapi(func) and
+  exists(ControlFlowNode callCfg | callCfg.getNode() = call | callCfg = get_a_call_objectapi(func)) and
   not get_function_or_initializer_objectapi(func).isLegalArgumentName(name)
 }
 
@@ -124,7 +124,7 @@ predicate illegally_named_parameter_objectapi(Call call, Object func, string nam
 predicate illegally_named_parameter(Call call, Value func, string name) {
   not func.isBuiltin() and
   name = call.getANamedArgumentName() and
-  call.getAFlowNode() = get_a_call(func) and
+  exists(ControlFlowNode callCfg | callCfg.getNode() = call | callCfg = get_a_call(func)) and
   not get_function_or_initializer(func).isLegalArgumentName(name)
 }
 
@@ -146,7 +146,9 @@ predicate too_few_args_objectapi(Call call, Object callable, int limit) {
     call = func.getAMethodCall().getNode() and limit = func.minParameters() - 1
     or
     callable instanceof ClassObject and
-    call.getAFlowNode() = get_a_call_objectapi(callable) and
+    exists(ControlFlowNode callCfg | callCfg.getNode() = call |
+      callCfg = get_a_call_objectapi(callable)
+    ) and
     limit = func.minParameters() - 1
   )
 }
@@ -172,7 +174,7 @@ predicate too_few_args(Call call, Value callable, int limit) {
     call = func.getAMethodCall().getNode() and limit = func.minParameters() - 1
     or
     callable instanceof ClassValue and
-    call.getAFlowNode() = get_a_call(callable) and
+    exists(ControlFlowNode callCfg | callCfg.getNode() = call | callCfg = get_a_call(callable)) and
     limit = func.minParameters() - 1
   )
 }
@@ -191,7 +193,9 @@ predicate too_many_args_objectapi(Call call, Object callable, int limit) {
     call = func.getAMethodCall().getNode() and limit = func.maxParameters() - 1
     or
     callable instanceof ClassObject and
-    call.getAFlowNode() = get_a_call_objectapi(callable) and
+    exists(ControlFlowNode callCfg | callCfg.getNode() = call |
+      callCfg = get_a_call_objectapi(callable)
+    ) and
     limit = func.maxParameters() - 1
   ) and
   positional_arg_count_for_call_objectapi(call, callable) > limit
@@ -211,7 +215,7 @@ predicate too_many_args(Call call, Value callable, int limit) {
     call = func.getAMethodCall().getNode() and limit = func.maxParameters() - 1
     or
     callable instanceof ClassValue and
-    call.getAFlowNode() = get_a_call(callable) and
+    exists(ControlFlowNode callCfg | callCfg.getNode() = call | callCfg = get_a_call(callable)) and
     limit = func.maxParameters() - 1
   ) and
   positional_arg_count_for_call(call, callable) > limit

python/ql/src/Expressions/DuplicateKeyInDictionaryLiteral.ql

@@ -36,11 +36,15 @@ where
   exists(string s | dict_key(d, k1, s) and dict_key(d, k2, s) and k1 != k2) and
   (
     exists(BasicBlock b, int i1, int i2 |
-      k1.getAFlowNode() = b.getNode(i1) and
+      b.getNode(i1).getNode() = k1 and
-      k2.getAFlowNode() = b.getNode(i2) and
+      b.getNode(i2).getNode() = k2 and
       i1 < i2
     )
     or
-    k1.getAFlowNode().getBasicBlock().strictlyDominates(k2.getAFlowNode().getBasicBlock())
+    exists(ControlFlowNode k1Cfg, ControlFlowNode k2Cfg |
+      k1Cfg.getNode() = k1 and k2Cfg.getNode() = k2
+    |
+      k1Cfg.getBasicBlock().strictlyDominates(k2Cfg.getBasicBlock())
+    )
   )
 select k1, "Dictionary key " + repr(k1) + " is subsequently $@.", k2, "overwritten"

python/ql/src/Expressions/Formatting/AdvancedFormatting.qll

@@ -98,16 +98,18 @@ private predicate brace_pair(PossibleAdvancedFormatString fmt, int start, int en
 }
 
 private predicate advanced_format_call(Call format_expr, PossibleAdvancedFormatString fmt, int args) {
-  exists(CallNode call | call = format_expr.getAFlowNode() |
+  exists(CallNode call, ControlFlowNode fmtCfg |
+    call.getNode() = format_expr and fmtCfg.getNode() = fmt
+  |
     call.getFunction().(ControlFlowNodeWithPointsTo).pointsTo(Value::named("format")) and
-    call.getArg(0).(ControlFlowNodeWithPointsTo).pointsTo(_, fmt.getAFlowNode()) and
+    call.getArg(0).(ControlFlowNodeWithPointsTo).pointsTo(_, fmtCfg) and
     args = count(format_expr.getAnArg()) - 1
     or
     call.getFunction()
         .(AttrNode)
         .getObject("format")
         .(ControlFlowNodeWithPointsTo)
-        .pointsTo(_, fmt.getAFlowNode()) and
+        .pointsTo(_, fmtCfg) and
     args = count(format_expr.getAnArg())
   )
 }

python/ql/src/Expressions/IncorrectComparisonUsingIs.ql

@@ -15,7 +15,7 @@ import python
 
 /** Holds if the comparison `comp` uses `is` or `is not` (represented as `op`) to compare its `left` and `right` arguments. */
 predicate comparison_using_is(Compare comp, ControlFlowNode left, Cmpop op, ControlFlowNode right) {
-  exists(CompareNode fcomp | fcomp = comp.getAFlowNode() |
+  exists(CompareNode fcomp | fcomp.getNode() = comp |
     fcomp.operands(left, op, right) and
     (op instanceof Is or op instanceof IsNot)
   )

python/ql/src/Expressions/IsComparisons.qll

@@ -5,7 +5,7 @@ private import LegacyPointsTo
 
 /** Holds if the comparison `comp` uses `is` or `is not` (represented as `op`) to compare its `left` and `right` arguments. */
 predicate comparison_using_is(Compare comp, ControlFlowNode left, Cmpop op, ControlFlowNode right) {
-  exists(CompareNode fcomp | fcomp = comp.getAFlowNode() |
+  exists(CompareNode fcomp | fcomp.getNode() = comp |
     fcomp.operands(left, op, right) and
     (op instanceof Is or op instanceof IsNot)
   )

python/ql/src/Expressions/TruncatedDivision.ql

@@ -19,7 +19,7 @@ where
   // Only relevant for Python 2, as all later versions implement true division
   major_version() = 2 and
   exists(BinaryExprNode bin, Value lval, Value rval |
-    bin = div.getAFlowNode() and
+    bin.getNode() = div and
     bin.getNode().getOp() instanceof Div and
     bin.getLeft().(ControlFlowNodeWithPointsTo).pointsTo(lval, left) and
     lval.getClass() = ClassValue::int_() and

python/ql/src/Functions/ExplicitReturnInInit.ql

@@ -19,7 +19,9 @@ where
   exists(Function init | init.isInitMethod() and r.getScope() = init) and
   r.getValue() = rv and
   not rv.pointsTo(Value::none_()) and
-  not exists(FunctionValue f | f.getACall() = rv.getAFlowNode() | f.neverReturns()) and
+  not exists(FunctionValue f, ControlFlowNode rvCfg | rvCfg.getNode() = rv |
+    f.getACall() = rvCfg and f.neverReturns()
+  ) and
   // to avoid double reporting, don't trigger if returning result from other __init__ function
   not exists(Attribute meth | meth = rv.(Call).getFunc() | meth.getName() = "__init__")
 select r, "Explicit return in __init__ method."

python/ql/src/Functions/ReturnValueIgnored.ql

@@ -69,7 +69,12 @@ where
   returns_meaningful_value(callee) and
   not wrapped_in_try_except(call) and
   exists(int unused |
-    unused = count(ExprStmt e | e.getValue().getAFlowNode() = callee.getACall()) and
+    unused =
+      count(ExprStmt e |
+        exists(ControlFlowNode eValCfg | eValCfg.getNode() = e.getValue() |
+          eValCfg = callee.getACall()
+        )
+      ) and
     total = count(callee.getACall())
   |
     percentage_used = (100.0 * (total - unused) / total).floor()

python/ql/src/Resources/FileOpen.qll

@@ -138,12 +138,12 @@ predicate function_opens_file(FunctionValue f) {
   f = Value::named("open")
   or
   exists(EssaVariable v, Return ret | ret.getScope() = f.getScope() |
-    ret.getValue().getAFlowNode() = v.getAUse() and
+    v.getNode() = ret.getValue().getAUse() and
     var_is_open(v, _)
   )
   or
   exists(Return ret, FunctionValue callee | ret.getScope() = f.getScope() |
-    ret.getValue().getAFlowNode() = callee.getACall() and
+    callee.getNode() = ret.getValue().getACall() and
     function_opens_file(callee)
   )
 }

python/ql/src/Security/CWE-798/HardcodedCredentials.ql

@@ -94,7 +94,7 @@ class CredentialSink extends DataFlow::Node {
         this.(DataFlow::ArgumentNode).argumentOf(_, pos)
       )
       or
-      exists(Keyword k | k.getArg() = name and k.getValue().getAFlowNode() = this.asCfgNode())
+      exists(Keyword k | k.getArg() = name and this.asCfgNode().getNode() = k.getValue())
       or
       exists(CompareNode cmp, NameNode n | n.getId() = name |
         cmp.operands(this.asCfgNode(), any(Eq eq), n)

python/ql/src/Statements/IterableStringOrSequence.ql

@@ -25,7 +25,7 @@ from
   For loop, ControlFlowNodeWithPointsTo iter, Value str, Value seq, ControlFlowNode seq_origin,
   ControlFlowNode str_origin
 where
-  loop.getIter().getAFlowNode() = iter and
+  iter.getNode() = loop.getIter() and
   iter.pointsTo(str, str_origin) and
   iter.pointsTo(seq, seq_origin) and
   has_string_type(str) and

python/ql/src/Statements/NestedLoopsSameVariableWithReuse.ql

@@ -15,7 +15,7 @@
 import python
 
 predicate loop_variable_ssa(For f, Variable v, SsaVariable s) {
-  f.getTarget().getAFlowNode() = s.getDefinition() and v = s.getVariable()
+  s.getDefinition().getNode() = f.getTarget() and v = s.getVariable()
 }
 
 predicate variableUsedInNestedLoops(For inner, For outer, Variable v, Name n) {

python/ql/src/Statements/NonIteratorInForLoop.ql

@@ -16,7 +16,7 @@ private import LegacyPointsTo
 
 from For loop, ControlFlowNodeWithPointsTo iter, Value v, ClassValue t, ControlFlowNode origin
 where
-  loop.getIter().getAFlowNode() = iter and
+  iter.getNode() = loop.getIter() and
   iter.pointsTo(_, v, origin) and
   v.getClass() = t and
   not t.isIterable() and

python/ql/src/Statements/SideEffectInAssert.ql

@@ -24,11 +24,13 @@ predicate func_with_side_effects(Expr e) {
 }
 
 predicate call_with_side_effect(Call e) {
-  e.getAFlowNode() =
+  exists(ControlFlowNode eCfg | eCfg.getNode() = e |
-    API::moduleImport("subprocess")
+    eCfg =
-        .getMember(["call", "check_call", "check_output"])
+      API::moduleImport("subprocess")
-        .getACall()
+          .getMember(["call", "check_call", "check_output"])
-        .asCfgNode()
+          .getACall()
+          .asCfgNode()
+  )
 }
 
 predicate probable_side_effect(Expr e) {

python/ql/src/Variables/Definition.qll

@@ -133,7 +133,11 @@ class ListComprehensionDeclaration extends ListComp {
     major_version() = 2 and
     this.getIterationVariable(_).getId() = result.getId() and
     result.getScope() = this.getScope() and
-    this.getAFlowNode().strictlyReaches(result.getAFlowNode()) and
+    exists(ControlFlowNode thisCfg, ControlFlowNode resultCfg |
+      thisCfg.getNode() = this and resultCfg.getNode() = result
+    |
+      thisCfg.strictlyReaches(resultCfg)
+    ) and
     result.isUse()
   }
 

python/ql/src/Variables/LeakingListComprehension.ql

@@ -13,18 +13,21 @@
 import python
 import Definition
 
-from ListComprehensionDeclaration l, Name use, Name defn
+from
+  ListComprehensionDeclaration l, Name use, Name defn, ControlFlowNode lCfg, ControlFlowNode useCfg
 where
   use = l.getALeakedVariableUse() and
   defn = l.getDefinition() and
-  l.getAFlowNode().strictlyReaches(use.getAFlowNode()) and
+  lCfg.getNode() = l and
+  useCfg.getNode() = use and
+  lCfg.strictlyReaches(useCfg) and
   /* Make sure we aren't in a loop, as the variable may be redefined */
-  not use.getAFlowNode().strictlyReaches(l.getAFlowNode()) and
+  not useCfg.strictlyReaches(lCfg) and
   not l.contains(use) and
   not use.deletes(_) and
   not exists(SsaVariable v |
-    v.getAUse() = use.getAFlowNode() and
+    v.getAUse() = useCfg and
-    not v.getDefinition().strictlyDominates(l.getAFlowNode())
+    not v.getDefinition().strictlyDominates(lCfg)
   )
 select use,
   use.getId() + " may have a different value in Python 3, as the $@ will not be in scope.", defn,

python/ql/src/Variables/Loop.qll

@@ -26,8 +26,11 @@ private Stmt loop_probably_defines(Variable v) {
 
 /** Holds if the variable used by `use` is probably defined in a loop */
 predicate probably_defined_in_loop(Name use) {
-  exists(Stmt loop | loop = loop_probably_defines(use.getVariable()) |
+  exists(Stmt loop, ControlFlowNode loopCfg, ControlFlowNode useCfg |
-    loop.getAFlowNode().strictlyReaches(use.getAFlowNode())
+    loop = loop_probably_defines(use.getVariable()) and
+    loopCfg.getNode() = loop and
+    useCfg.getNode() = use and
+    loopCfg.strictlyReaches(useCfg)
   )
 }
 

python/ql/src/Variables/MultiplyDefined.ql

@@ -24,8 +24,8 @@ predicate multiply_defined(AstNode asgn1, AstNode asgn2, Variable v) {
 
   forex(Definition def, Definition redef |
     def.getVariable() = v and
-    def = asgn1.getAFlowNode() and
+    def.getNode() = asgn1 and
-    redef = asgn2.getAFlowNode()
+    redef.getNode() = asgn2
   |
     def.isUnused() and
     def.getARedef() = redef and

python/ql/src/Variables/SuspiciousUnusedLoopIterationVariable.ql

@@ -88,7 +88,9 @@ predicate implicit_repeat(For f) {
  * E.g. gets `x` from `{ y for y in x }`.
  */
 ControlFlowNode get_comp_iterable(For f) {
-  exists(Comp c | c.getFunction().getStmt(0) = f | c.getAFlowNode().getAPredecessor() = result)
+  exists(Comp c, ControlFlowNode cCfg |
+    c.getFunction().getStmt(0) = f and cCfg.getNode() = c and cCfg.getAPredecessor() = result
+  )
 }
 
 from For f, Variable v, string msg

python/ql/src/Variables/Undefined.qll

@@ -19,9 +19,10 @@ private predicate loop_entry_variables(EssaVariable pred, EssaVariable succ) {
 private predicate loop_entry_edge(BasicBlock pred, BasicBlock loop) {
   pred = loop.getAPredecessor() and
   pred = loop.getImmediateDominator() and
-  exists(Stmt s |
+  exists(Stmt s, ControlFlowNode sCfg |
     loop_probably_executes_at_least_once(s) and
-    s.getAFlowNode().getBasicBlock() = loop
+    sCfg.getNode() = s and
+    sCfg.getBasicBlock() = loop
   )
 }
 

python/ql/src/Variables/UndefinedGlobal.ql

@@ -27,7 +27,7 @@ predicate guarded_against_name_error(Name u) {
   |
     globals.getFunc().(Name).getId() = "globals" and
     guard.controls(controlled, _) and
-    controlled.contains(u.getAFlowNode())
+    exists(ControlFlowNode uCfg | uCfg.getNode() = u | controlled.contains(uCfg))
   )
 }
 
@@ -101,18 +101,18 @@ predicate undefined_use(Name u) {
 }
 
 private predicate first_use_in_a_block(Name use) {
-  exists(GlobalVariable v, BasicBlock b, int i |
+  exists(GlobalVariable v, BasicBlock b, int i, ControlFlowNode useCfg | useCfg.getNode() = use |
-    i = min(int j | b.getNode(j).getNode() = v.getALoad()) and b.getNode(i) = use.getAFlowNode()
+    i = min(int j | b.getNode(j).getNode() = v.getALoad()) and b.getNode(i) = useCfg
   )
 }
 
 predicate first_undefined_use(Name use) {
   undefined_use(use) and
-  exists(GlobalVariable v | v.getALoad() = use |
+  exists(GlobalVariable v, ControlFlowNode useCfg | v.getALoad() = use and useCfg.getNode() = use |
     first_use_in_a_block(use) and
     not exists(ControlFlowNode other |
       other.getNode() = v.getALoad() and
-      other.getBasicBlock().strictlyDominates(use.getAFlowNode().getBasicBlock())
+      other.getBasicBlock().strictlyDominates(useCfg.getBasicBlock())
     )
   )
 }

python/ql/src/Variables/UndefinedPlaceHolder.ql

@@ -18,8 +18,8 @@ private import semmle.python.types.ImportTime
 
 /* Local variable part */
 predicate initialized_as_local(PlaceHolder use) {
-  exists(SsaVariableWithPointsTo l, Function f |
+  exists(SsaVariableWithPointsTo l, Function f, ControlFlowNode useCfg |
-    f = use.getScope() and l.getAUse() = use.getAFlowNode()
+    f = use.getScope() and useCfg.getNode() = use and l.getAUse() = useCfg
   |
     l.getVariable() instanceof LocalVariable and
     not l.maybeUndefined()

python/ql/src/Variables/UnusedModuleVariable.ql

@@ -54,7 +54,7 @@ predicate unused_global(Name unused, GlobalVariable v) {
       u.uses(v)
     |
       // That is reachable from this definition, directly
-      defn.strictlyReaches(u.getAFlowNode())
+      exists(ControlFlowNode uCfg | uCfg.getNode() = u | defn.strictlyReaches(uCfg))
       or
       // indirectly
       defn.getBasicBlock().reachesExit() and u.getScope() != unused.getScope()

python/ql/src/analysis/CrossProjectDefinitions.qll

@@ -48,15 +48,17 @@ class Symbol extends TSymbol {
   AstNode find() {
     this = TModule(result)
     or
-    exists(Symbol s, string name | this = TMember(s, name) |
+    exists(Symbol s, string name, ControlFlowNode resultCfg |
+      this = TMember(s, name) and resultCfg.getNode() = result
+    |
       exists(ClassObject cls |
         s.resolvesTo() = cls and
-        cls.attributeRefersTo(name, _, result.getAFlowNode())
+        cls.attributeRefersTo(name, _, resultCfg)
       )
       or
       exists(ModuleObject m |
         s.resolvesTo() = m and
-        m.attributeRefersTo(name, _, result.getAFlowNode())
+        m.attributeRefersTo(name, _, resultCfg)
       )
     )
   }

python/ql/src/analysis/ImportFailure.ql

@@ -80,10 +80,11 @@ class VersionGuard extends ConditionBlock {
   VersionGuard() { this.getLastNode() instanceof VersionTest }
 }
 
-from ImportExpr ie
+from ImportExpr ie, ControlFlowNode ieCfg
 where
+  ieCfg.getNode() = ie and
   not ie.(ExprWithPointsTo).refersTo(_) and
-  exists(Context c | c.appliesTo(ie.getAFlowNode())) and
+  exists(Context c | c.appliesTo(ieCfg)) and
   not ok_to_fail(ie) and
-  not exists(VersionGuard guard | guard.controls(ie.getAFlowNode().getBasicBlock(), _))
+  not exists(VersionGuard guard | guard.controls(ieCfg.getBasicBlock(), _))
 select ie, "Unable to resolve import of '" + ie.getImportedModuleName() + "'."

python/ql/src/analysis/KeyPointsToFailure.ql

@@ -11,13 +11,13 @@ import python
 import semmle.python.pointsto.PointsTo
 
 predicate points_to_failure(Expr e) {
-  exists(ControlFlowNode f | f = e.getAFlowNode() | not PointsTo::pointsTo(f, _, _, _))
+  exists(ControlFlowNode f | f.getNode() = e | not PointsTo::pointsTo(f, _, _, _))
 }
 
 predicate key_points_to_failure(Expr e) {
   points_to_failure(e) and
   not points_to_failure(e.getASubExpression()) and
-  not exists(SsaVariable ssa | ssa.getAUse() = e.getAFlowNode() |
+  not exists(SsaVariable ssa, ControlFlowNode eCfg | eCfg.getNode() = e and ssa.getAUse() = eCfg |
     points_to_failure(ssa.getAnUltimateDefinition().getDefinition().getNode())
   ) and
   not exists(Assign a | a.getATarget() = e)

python/ql/src/analysis/PointsToFailure.ql

@@ -12,5 +12,5 @@ import python
 private import LegacyPointsTo
 
 from Expr e
-where exists(ControlFlowNodeWithPointsTo f | f = e.getAFlowNode() | not f.refersTo(_))
+where exists(ControlFlowNodeWithPointsTo f | f.getNode() = e | not f.refersTo(_))
 select e, "Expression does not 'point-to' any object."

python/ql/src/semmle/python/functions/ModificationOfParameterWithDefaultCustomizations.qll

@@ -131,7 +131,7 @@ module ModificationOfParameterWithDefault {
       exists(DeletionNode d | d.getTarget().(SubscriptNode).getObject() = this.asCfgNode())
       or
       // augmented assignment to the value
-      exists(AugAssign a | a.getTarget().getAFlowNode() = this.asCfgNode())
+      exists(AugAssign a | this.asCfgNode().getNode() = a.getTarget())
       or
       // modifying function call
       exists(DataFlow::CallCfgNode c, DataFlow::AttrRead a | c.getFunction() = a |

python/ql/test/2/library-tests/comprehensions/ConsistencyCheck.ql

@@ -5,5 +5,7 @@
 import python
 
 select count(Comprehension c |
-    count(c.toString()) != 1 or count(c.getLocation()) != 1 or not exists(c.getAFlowNode())
+    count(c.toString()) != 1 or
+    count(c.getLocation()) != 1 or
+    not exists(ControlFlowNode n | n.getNode() = c)
   )

python/ql/test/experimental/import-resolution/importflow.ql

@@ -45,13 +45,15 @@ private class VersionGuardedNode extends DataFlow::Node {
 
   VersionGuardedNode() {
     version in [2, 3] and
-    exists(If parent, CompareNode c | parent.getBody().contains(this.asExpr()) |
+    exists(If parent, CompareNode c, ControlFlowNode litCfg |
+      parent.getBody().contains(this.asExpr()) and
+      litCfg.getNode() = any(IntegerLiteral lit | lit.getValue() = version)
+    |
       c.operands(API::moduleImport("sys")
             .getMember("version_info")
             .getASubscript()
             .asSource()
-            .asCfgNode(), any(Eq eq),
+            .asCfgNode(), any(Eq eq), litCfg)
-        any(IntegerLiteral lit | lit.getValue() = version).getAFlowNode())
     )
   }
 

python/ql/test/extractor-tests/syntax_error/CONSISTENCY/CfgConsistency.expected

@@ -0,0 +1,4 @@
+consistencyOverview
+| deadEnd | 1 |
+deadEnd
+| without_loop.py:7:5:7:9 | Break |

python/ql/test/library-tests/ControlFlow/PointsToSupport/UseFromDefinition.ql

@@ -9,7 +9,7 @@ Expr assignedValue(Name n) {
 
 from Name def, DefinitionNode d
 where
-  d = def.getAFlowNode() and
+  d.getNode() = def and
   exists(assignedValue(def)) and
   not d.getValue().getNode() = assignedValue(def)
 select def.toString(), assignedValue(def)

python/ql/test/library-tests/ControlFlow/bindings/BindingsTest.ql

@@ -0,0 +1,32 @@
+/**
+ * Phase -1 of the dataflow CFG migration: verifies that every variable
+ * binding visible to the AST (`Name.defines(v)`) corresponds to a CFG node
+ * in the new CFG (`semmle.python.controlflow.internal.AstNodeImpl`).
+ *
+ * The expected tag is `cfgdefines=<name>`. Each binding annotation in the
+ * test sources looks like `# $ cfgdefines=x` for a binding currently
+ * covered by the new CFG, or `# $ MISSING: cfgdefines=x` for a binding
+ * that is known to be uncovered (a "red" test case that should be
+ * green-flipped once the corresponding `cfg-ext-*` extension lands).
+ */
+
+import python
+import semmle.python.controlflow.internal.AstNodeImpl as CfgImpl
+import utils.test.InlineExpectationsTest
+
+module CfgBindingsTest implements TestSig {
+  string getARelevantTag() { result = "cfgdefines" }
+
+  predicate hasActualResult(Location location, string element, string tag, string value) {
+    exists(Name n, Variable v, CfgImpl::ControlFlowNode cfg |
+      n.defines(v) and
+      cfg.getAstNode().asExpr() = n and
+      location = n.getLocation() and
+      element = n.toString() and
+      tag = "cfgdefines" and
+      value = v.getId()
+    )
+  }
+}
+
+import MakeTest<CfgBindingsTest>

python/ql/test/library-tests/ControlFlow/bindings/annassign.py

@@ -0,0 +1,13 @@
+# Annotated assignment (PEP 526). Both with and without an initializer.
+
+a: int = 1  # $ cfgdefines=a
+b: str = "hi"  # $ cfgdefines=b
+
+# Annotation without value: the AST records `c` as defined,
+# and the new CFG now visits it via the AnnAssignStmt wrapper.
+c: int  # $ cfgdefines=c
+
+class K:  # $ cfgdefines=K
+    field: int = 0  # $ cfgdefines=field
+
+

python/ql/test/library-tests/ControlFlow/bindings/compound.py

@@ -0,0 +1,14 @@
+# Compound (tuple/list) assignment targets — actually wired in the new CFG.
+
+a, b = (1, 2)  # $ cfgdefines=a cfgdefines=b
+[c, d] = [3, 4]  # $ cfgdefines=c cfgdefines=d
+
+# Nested unpacking.
+(e, (f, g)) = (1, (2, 3))  # $ cfgdefines=e cfgdefines=f cfgdefines=g
+
+# Star unpacking.
+h, *i = [1, 2, 3]  # $ cfgdefines=h cfgdefines=i
+
+# Chained assignment with compound target.
+j = k, l = (5, 6)  # $ cfgdefines=j cfgdefines=k cfgdefines=l
+

python/ql/test/library-tests/ControlFlow/bindings/comprehension.py

@@ -0,0 +1,21 @@
+# Comprehension and `for` loop targets — wired in the new CFG.
+# Comprehensions are nested function scopes with a synthetic `.0` parameter
+# bound to the iterable.
+
+# Bare-name `for` target.
+for i in range(3):  # $ cfgdefines=i
+    pass
+
+# Compound `for` target.
+for k, v in [(1, 2)]:  # $ cfgdefines=k cfgdefines=v
+    pass
+
+# Comprehension targets.
+_ = [x for x in range(3)]  # $ cfgdefines=_ cfgdefines=x cfgdefines=.0
+_ = {y: z for y, z in []}  # $ cfgdefines=_ cfgdefines=y cfgdefines=z cfgdefines=.0
+_ = (a for a in [])  # $ cfgdefines=_ cfgdefines=a cfgdefines=.0
+
+# Nested comprehensions.
+_ = [b for c in [] for b in c]  # $ cfgdefines=_ cfgdefines=c cfgdefines=b cfgdefines=.0
+
+

python/ql/test/library-tests/ControlFlow/bindings/dead_under_no_raise.py

@@ -0,0 +1,52 @@
+# Dead bindings under the "no expressions raise" CFG abstraction.
+#
+# The new CFG does not currently model raise edges from arbitrary
+# expressions. As a consequence, code that is only reachable through
+# exception flow is (correctly) classified as dead and has no CFG node.
+# Variable bindings in dead code do not need CFG nodes - SSA / dataflow
+# over dead code is moot.
+#
+# These tests act as a regression guard: the bindings below intentionally
+# have no `cfgdefines=` annotations. If raise modelling is later added,
+# the BindingsTest infrastructure will surface the new CFG nodes as
+# unexpected results, and this file will need to be revisited.
+
+
+def f(obj):  # $ cfgdefines=f cfgdefines=obj
+    try:
+        return len(obj)
+    except TypeError:
+        pass
+
+    # The first try's body always returns; its except handler does not
+    # raise or otherwise transfer control, so under "no expressions
+    # raise" the only paths out of the try-statement are dead. Everything
+    # below is unreachable.
+    try:
+        hint = type(obj).__length_hint__
+    except AttributeError:
+        return None
+    return hint
+
+
+def g():  # $ cfgdefines=g
+    try:
+        raise Exception("inner")
+    except:
+        raise Exception("outer")
+    else:
+        # Unreachable: the inner try body always raises, so the `else:`
+        # clause never runs.
+        hit_inner_else = True
+
+
+def h(cache, key):  # $ cfgdefines=h cfgdefines=cache cfgdefines=key
+    try:
+        return cache[key]
+    except KeyError:
+        pass
+
+    # Same pattern as `f`: dead under "no expressions raise".
+    value = compute(key)
+    cache[key] = value
+    return value

python/ql/test/library-tests/ControlFlow/bindings/decorated.py

@@ -0,0 +1,30 @@
+# Decorated `def`/`class` — wired in the new CFG.
+
+
+def deco(f):  # $ cfgdefines=deco cfgdefines=f
+    return f
+
+
+@deco
+def decorated_func():  # $ cfgdefines=decorated_func
+    pass
+
+
+@deco
+class DecoratedClass:  # $ cfgdefines=DecoratedClass
+    pass
+
+
+# Stacked decorators.
+@deco
+@deco
+def doubly():  # $ cfgdefines=doubly
+    pass
+
+
+# Inside a class body.
+class Outer:  # $ cfgdefines=Outer
+    @staticmethod
+    def inner():  # $ cfgdefines=inner
+        pass
+

python/ql/test/library-tests/ControlFlow/bindings/except_handler.py

@@ -0,0 +1,19 @@
+# Exception-handler name bindings. These are already wired in the new
+# CFG provided the try body can raise; `raise` statements are reliably
+# treated as exception sources.
+
+try:
+    raise ValueError("oops")
+except ValueError as e:  # $ cfgdefines=e
+    pass
+
+try:
+    raise TypeError("oops")
+except (TypeError, KeyError) as err:  # $ cfgdefines=err
+    pass
+
+# Exception groups (Python 3.11+).
+try:
+    raise ValueError("oops")
+except* ValueError as eg:  # $ cfgdefines=eg
+    pass

python/ql/test/library-tests/ControlFlow/bindings/imports.py

@@ -0,0 +1,14 @@
+# Import aliases — all bound names below are now reachable via the new
+# CFG's `ImportStmt` wrapper.
+
+import os  # $ cfgdefines=os
+import os.path  # $ cfgdefines=os
+import os as o  # $ cfgdefines=o
+from os import path  # $ cfgdefines=path
+from os import path as p  # $ cfgdefines=p
+from os import sep, linesep  # $ cfgdefines=sep cfgdefines=linesep
+from os import (
+    getcwd,  # $ cfgdefines=getcwd
+    getcwdb,  # $ cfgdefines=getcwdb
+)
+

python/ql/test/library-tests/ControlFlow/bindings/match_pattern.py

@@ -0,0 +1,24 @@
+# Match-statement pattern bindings — wired in the new CFG.
+
+def f(subject):  # $ cfgdefines=f cfgdefines=subject
+    match subject:
+        case x:  # $ cfgdefines=x
+            pass
+        case [a, b]:  # $ cfgdefines=a cfgdefines=b
+            pass
+        case {"k": v}:  # $ cfgdefines=v
+            pass
+        case Point(p, q):  # $ cfgdefines=p cfgdefines=q
+            pass
+        case [_, *rest]:  # $ cfgdefines=rest
+            pass
+        case (1 | 2) as n:  # $ cfgdefines=n
+            pass
+
+
+class Point:  # $ cfgdefines=Point
+    __match_args__ = ("x", "y")  # $ cfgdefines=__match_args__
+    x: int  # $ cfgdefines=x
+    y: int  # $ cfgdefines=y
+
+

python/ql/test/library-tests/ControlFlow/bindings/parameters.py

@@ -0,0 +1,42 @@
+# Function parameters.
+
+def positional(a, b):  # $ cfgdefines=positional cfgdefines=a cfgdefines=b
+    pass
+
+
+def with_default(x=1, y=2):  # $ cfgdefines=with_default cfgdefines=x cfgdefines=y
+    pass
+
+
+def with_vararg(*args):  # $ cfgdefines=with_vararg cfgdefines=args
+    pass
+
+
+def with_kwarg(**kwargs):  # $ cfgdefines=with_kwarg cfgdefines=kwargs
+    pass
+
+
+def with_kwonly(*, k1, k2=5):  # $ cfgdefines=with_kwonly cfgdefines=k1 cfgdefines=k2
+    pass
+
+
+def kitchen_sink(a, b=2, *args, k1, k2=5, **kw):  # $ cfgdefines=kitchen_sink cfgdefines=a cfgdefines=b cfgdefines=args cfgdefines=k1 cfgdefines=k2 cfgdefines=kw
+    pass
+
+
+# Methods get `self` / `cls`.
+class C:  # $ cfgdefines=C
+    def method(self, x):  # $ cfgdefines=method cfgdefines=self cfgdefines=x
+        pass
+
+    @classmethod
+    def cmethod(cls, x):  # $ cfgdefines=cmethod cfgdefines=cls cfgdefines=x
+        pass
+
+
+# Lambda parameter.
+_ = lambda p: p + 1  # $ cfgdefines=_ cfgdefines=p
+
+# PEP 570 positional-only.
+def pos_only(a, b, /, c):  # $ cfgdefines=pos_only cfgdefines=a cfgdefines=b cfgdefines=c
+    pass

python/ql/test/library-tests/ControlFlow/bindings/simple.py

@@ -0,0 +1,14 @@
+# Simple bindings that should already work in the new CFG.
+# No MISSING annotations expected.
+
+x = 1  # $ cfgdefines=x
+y = x + 1  # $ cfgdefines=y
+
+def f():  # $ cfgdefines=f
+    pass
+
+class C:  # $ cfgdefines=C
+    pass
+
+# Re-assignment.
+x = 2  # $ cfgdefines=x

python/ql/test/library-tests/ControlFlow/bindings/type_params.py

@@ -0,0 +1,21 @@
+# PEP 695 type parameters (Python 3.12+).
+
+# PEP 695 type-param names on `def`/`class` bind in an annotation scope
+# that nests the function/class body — they have no CFG node in the
+# enclosing scope (matching the legacy CFG).
+def func[T](x: T) -> T:  # $ cfgdefines=func cfgdefines=x
+    return x
+
+
+class Box[T]:  # $ cfgdefines=Box
+    item: T  # $ cfgdefines=item
+
+
+# Multi-parameter, with bound and variadics.
+def multi[T: int, *Ts, **P](x: T, *args: *Ts, **kwargs: P.kwargs) -> T:  # $ cfgdefines=multi cfgdefines=x cfgdefines=args cfgdefines=kwargs
+    return x
+
+
+# `type` statement (PEP 695).
+type Alias[T] = list[T]  # $ cfgdefines=Alias cfgdefines=T
+

python/ql/test/library-tests/ControlFlow/bindings/walrus_starred.py

@@ -0,0 +1,14 @@
+# Walrus and starred-target edge cases — wired in the new CFG.
+
+# Walrus in expression context.
+if (y := 5) > 0:  # $ cfgdefines=y
+    pass
+
+# Walrus in a comprehension. The comprehension introduces a synthetic
+# `.0` parameter bound to the iterable.
+_ = [w for _ in range(3) if (w := 1)]  # $ cfgdefines=_ cfgdefines=w cfgdefines=.0
+
+# Starred target in a Tuple LHS.
+*head, tail = [1, 2, 3]  # $ cfgdefines=head cfgdefines=tail
+
+

python/ql/test/library-tests/ControlFlow/bindings/with_stmt.py

@@ -0,0 +1,21 @@
+# `with cm() as x:` bindings — wired in the new CFG.
+
+class CM:  # $ cfgdefines=CM
+    def __enter__(self): return self  # $ cfgdefines=__enter__ cfgdefines=self
+    def __exit__(self, *a): pass  # $ cfgdefines=__exit__ cfgdefines=self cfgdefines=a
+
+with CM() as x:  # $ cfgdefines=x
+    pass
+
+# Multiple items.
+with CM() as a, CM() as b:  # $ cfgdefines=a cfgdefines=b
+    pass
+
+# Parenthesised form (Python 3.10+).
+with (CM() as p, CM() as q):  # $ cfgdefines=p cfgdefines=q
+    pass
+
+# Compound target in `with`.
+with CM() as (m, n):  # $ cfgdefines=m cfgdefines=n
+    pass
+

python/ql/test/library-tests/ControlFlow/evaluation-order/AllLiveReachable.ql

@@ -5,6 +5,8 @@
  * have separate CFGs and are excluded from this check.
  */
 
+import python
+import TimerUtils
 import OldCfgImpl
 
 private module Utils = EvalOrderCfgUtils<OldCfg>;