Merge pull request github#9419 from github/revert-9373-cfg-for-key-paths

Revert "Swift: Control-flow for key paths"

Author: AlexDenisov

swift/ql/lib/codeql/swift/controlflow/BasicBlocks.qll

@@ -207,10 +207,6 @@ private module JoinBlockPredecessors {
     isPropertySetterElement(n, _, result)
     or
     isPropertyObserverElement(n, _, result)
-    or
-    result = n.(KeyPathElement).getAst()
-    or
-    result = n.(FuncDeclElement).getAst()
   }
 
   int getId(JoinBlockPredecessor jbp) {

swift/ql/lib/codeql/swift/controlflow/internal/ControlFlowElements.qll

@@ -10,8 +10,7 @@ newtype TControlFlowElement =
   } or
   TPropertyObserverElement(AccessorDecl observer, AssignExpr assign) {
     isPropertyObserverElement(observer, assign)
-  } or
-  TKeyPathElement(KeyPathExpr expr)
+  }
 
 predicate isLValue(Expr e) { any(AssignExpr assign).getDest() = e }
 
@@ -172,18 +171,4 @@ class FuncDeclElement extends ControlFlowElement, TFuncDeclElement {
   override string toString() { result = func.toString() }
 
   override Location getLocation() { result = func.getLocation() }
-
-  AbstractFunctionDecl getAst() { result = func }
-}
-
-class KeyPathElement extends ControlFlowElement, TKeyPathElement {
-  KeyPathExpr expr;
-
-  KeyPathElement() { this = TKeyPathElement(expr) }
-
-  override Location getLocation() { result = expr.getLocation() }
-
-  KeyPathExpr getAst() { result = expr }
-
-  override string toString() { result = expr.toString() }
 }

swift/ql/lib/codeql/swift/controlflow/internal/ControlFlowGraphImpl.qll

@@ -47,23 +47,19 @@ module CfgScope {
   }
 
   private class BodyStmtCallableScope extends Range_ instanceof AbstractFunctionDecl {
-    Decls::FuncDeclTree tree;
-
-    BodyStmtCallableScope() { tree.getAst() = this }
-
-    final override predicate entry(ControlFlowElement first) { first(tree, first) }
-
-    final override predicate exit(ControlFlowElement last, Completion c) { last(tree, last, c) }
-  }
-
-  private class KeyPathScope extends Range_ instanceof KeyPathExpr {
-    AstControlFlowTree tree;
-
-    KeyPathScope() { tree.getAst() = this.getParsedRoot().getFullyConverted() }
-
-    final override predicate entry(ControlFlowElement first) { first(tree, first) }
+    final override predicate entry(ControlFlowElement first) {
+      exists(Decls::FuncDeclTree tree |
+        tree.getAst() = this and
+        first = tree
+      )
+    }
 
-    final override predicate exit(ControlFlowElement last, Completion c) { last(tree, last, c) }
+    final override predicate exit(ControlFlowElement last, Completion c) {
+      exists(Decls::FuncDeclTree tree |
+        tree.getAst() = this and
+        tree.last(last, c)
+      )
+    }
   }
 }
 
@@ -1116,20 +1112,6 @@ module Exprs {
     }
   }
 
-  class KeyPathTree extends AstLeafTree {
-    override KeyPathExpr ast;
-  }
-
-  class KeyPathApplicationTree extends AstStandardPostOrderTree {
-    override KeyPathApplicationExpr ast;
-
-    final override ControlFlowElement getChildElement(int i) {
-      i = 0 and result.asAstNode() = ast.getBase().getFullyConverted()
-      or
-      i = 1 and result.asAstNode() = ast.getKeyPath().getFullyConverted()
-    }
-  }
-
   private class InOutTree extends AstStandardPostOrderTree {
     override InOutExpr ast;
 
@@ -1666,9 +1648,7 @@ private module Cached {
     result = scopeOfAst(n.asAstNode()) or
     result = scopeOfAst(n.(PropertyGetterElement).getRef()) or
     result = scopeOfAst(n.(PropertySetterElement).getAssignExpr()) or
-    result = scopeOfAst(n.(PropertyObserverElement).getAssignExpr()) or
-    result = n.(FuncDeclElement).getAst() or
-    result = n.(KeyPathElement).getAst()
+    result = scopeOfAst(n.(PropertyObserverElement).getAssignExpr())
   }
 
   cached

swift/ql/lib/codeql/swift/controlflow/internal/Scope.qll

@@ -2,7 +2,7 @@ private import swift
 private import codeql.swift.generated.GetImmediateParent
 
 module CallableBase {
-  class TypeRange = @abstract_function_decl or @key_path_expr;
+  class TypeRange = @abstract_function_decl;
 
   class Range extends Scope::Range, TypeRange { }
 }

swift/ql/lib/codeql/swift/dataflow/internal/DataFlowDispatch.qll

@@ -1,7 +1,6 @@
 private import swift
 private import DataFlowPrivate
 private import DataFlowPublic
-private import codeql.swift.controlflow.ControlFlowGraph
 
 newtype TReturnKind = TNormalReturnKind()
 
@@ -54,7 +53,7 @@ class DataFlowCall extends ExprNode {
 cached
 private module Cached {
   cached
-  newtype TDataFlowCallable = TDataFlowFunc(CfgScope scope)
+  newtype TDataFlowCallable = TDataFlowFunc(FuncDecl func)
 
   /** Gets a viable run-time target for the call `call`. */
   cached