[For-Loop Reconstruction] Not handling "continue" instructions correc…

…tly (#320)

Co-authored-by: fnhartmann <[email protected]>
Co-authored-by: fnhartmann <[email protected]>

decompiler/pipeline/controlflowanalysis/readability_based_refinement.py

@@ -287,6 +287,9 @@ def run(self):
  or self._invalid_simple_for_loop_condition_type(loop_node.condition):
  continue
 
+ if any(node.does_end_with_continue for node in loop_node.body.get_descendant_code_nodes_interrupting_ancestor_loop()):
+ continue
+
  if not self._force_for_loops and loop_node.condition.get_complexity(self._ast.condition_map) > self._condition_max_complexity:
  continue
 

tests/pipeline/controlflowanalysis/test_readability_based_refinement.py

@@ -4,6 +4,7 @@
 from decompiler.pipeline.controlflowanalysis.readability_based_refinement import (
  ForLoopVariableRenamer,
  ReadabilityBasedRefinement,
+ WhileLoopReplacer,
  WhileLoopVariableRenamer,
  _find_continuation_instruction,
  _has_deep_requirement,
@@ -19,6 +20,7 @@
  Call,
  Condition,
  Constant,
+ Continue,
  ImportedFunctionSymbol,
  ListOperation,
  OperationType,
@@ -2077,3 +2079,114 @@ def test_declaration_listop(self, ast_call_for_loop):
  for node in ast_call_for_loop:
  if isinstance(node, ForLoopNode):
  assert node.declaration.destination.operands[0].name == "i"
+
+ def test_skip_for_loop_recovery_if_continue_in_while(self):
+ """
+ a = 0
+ while(a < 10) {
+ if(a == 2) {
+ a = a + 2
+ continue
+ }
+ a = a + 1
+ }
+ """
+ true_value = LogicCondition.initialize_true(context := LogicCondition.generate_new_context())
+ ast = AbstractSyntaxTree(
+ root := SeqNode(true_value),
+ condition_map={
+ logic_cond("x1", context): Condition(OperationType.less, [Variable("a"), Constant(10)]),
+ logic_cond("x2", context): Condition(OperationType.equal, [Variable("a"), Constant(2)])
+ }
+ )
+
+ true_branch = ast._add_code_node(
+ [
+ Assignment(Variable("a"), BinaryOperation(OperationType.plus, [Variable("a"), Constant(2)])),
+ Continue()
+ ]
+ )
+ if_condition = ast._add_condition_node_with(logic_cond("x2", context), true_branch)
+
+ init_code_node = ast._add_code_node([Assignment(Variable("a"), Constant(0))])
+
+ while_loop = ast.factory.create_while_loop_node(logic_cond("x1", context))
+ while_loop_body = ast.factory.create_seq_node()
+ while_loop_iteration = ast._add_code_node([Assignment(Variable("a"), BinaryOperation(OperationType.plus, [Variable("a"), Constant(1)]))])
+ ast._add_node(while_loop)
+ ast._add_node(while_loop_body)
+
+ ast._add_edges_from(
+ [
+ (root, init_code_node),
+ (root, while_loop),
+ (while_loop, while_loop_body),
+ (while_loop_body, if_condition),
+ (while_loop_body, while_loop_iteration)
+ ]
+ )
+
+ WhileLoopReplacer(ast, _generate_options()).run()
+ assert not any(isinstance(loop_node, ForLoopNode) for loop_node in list(ast.get_loop_nodes_post_order()))
+
+ def test_skip_for_loop_recovery_if_continue_in_nested_while(self):
+ """
+ while(a < 5) {
+ a = a + b
+ while(b < 10) {
+ if(b < 0) {
+ b = b + 2
+ continue
+ }
+ b = b + 1
+ }
+ a = a + 1
+ }
+ """
+ true_value = LogicCondition.initialize_true(context := LogicCondition.generate_new_context())
+ ast = AbstractSyntaxTree(
+ root := SeqNode(true_value),
+ condition_map={
+ logic_cond("x1", context): Condition(OperationType.less, [Variable("a"), Constant(5)]),
+ logic_cond("x2", context): Condition(OperationType.less, [Variable("b"), Constant(10)]),
+ logic_cond("x3", context): Condition(OperationType.less, [Variable("b"), Constant(0)])
+ }
+ )
+
+ true_branch = ast._add_code_node(
+ [
+ Assignment(Variable("b"), BinaryOperation(OperationType.plus, [Variable("b"), Constant(2)])),
+ Continue()
+ ]
+ )
+ if_condition = ast._add_condition_node_with(logic_cond("x3", context), true_branch)
+
+ while_loop_outer = ast.factory.create_while_loop_node(logic_cond("x1", context))
+ while_loop_body_outer = ast.factory.create_seq_node()
+ while_loop_iteration_outer_1 = ast._add_code_node([Assignment(Variable("a"), BinaryOperation(OperationType.plus, [Variable("a"), Variable("b")]))])
+ while_loop_iteration_outer_2 = ast._add_code_node([Assignment(Variable("a"), BinaryOperation(OperationType.plus, [Variable("a"), Constant(1)]))])
+ ast._add_node(while_loop_outer)
+ ast._add_node(while_loop_body_outer)
+
+ while_loop_inner = ast.factory.create_while_loop_node(logic_cond("x2", context))
+ while_loop_body_inner = ast.factory.create_seq_node()
+ while_loop_iteration_inner = ast._add_code_node([Assignment(Variable("b"), BinaryOperation(OperationType.plus, [Variable("b"), Constant(1)]))])
+ ast._add_node(while_loop_inner)
+ ast._add_node(while_loop_body_inner)
+
+ ast._add_edges_from(
+ [
+ (root, while_loop_outer),
+ (while_loop_outer, while_loop_body_outer),
+ (while_loop_body_outer, while_loop_inner),
+ (while_loop_body_outer, while_loop_iteration_outer_1),
+ (while_loop_body_outer, while_loop_iteration_outer_2),
+ (while_loop_inner, while_loop_body_inner),
+ (while_loop_body_inner, if_condition),
+ (while_loop_body_inner, while_loop_iteration_inner)
+ ]
+ )
+
+ WhileLoopReplacer(ast, _generate_options()).run()
+ loop_nodes = list(ast.get_loop_nodes_post_order())
+ assert not isinstance(loop_nodes[0], ForLoopNode) and isinstance(loop_nodes[1], ForLoopNode)