""" Use lldb Python API to test dynamic values in C++ """ import lldb from lldbsuite.test.decorators import * from lldbsuite.test.lldbtest import * from lldbsuite.test import lldbutil class DynamicValueTestCase(TestBase): def setUp(self): # Call super's setUp(). TestBase.setUp(self) # Find the line number to break for main.c. self.do_something_line = line_number( "pass-to-base.cpp", "// Break here in doSomething." ) self.main_first_call_line = line_number( "pass-to-base.cpp", "// Break here and get real addresses of myB and otherB.", ) self.main_second_call_line = line_number( "pass-to-base.cpp", "// Break here and get real address of reallyA." ) @add_test_categories(["pyapi"]) @expectedFailureAll(oslist=["windows"], bugnumber="llvm.org/pr24663") def test_get_dynamic_vals(self): """Test fetching C++ dynamic values from pointers & references.""" self.build() exe = self.getBuildArtifact("a.out") # Create a target from the debugger. target = self.dbg.CreateTarget(exe) self.assertTrue(target, VALID_TARGET) # Set up our breakpoints: do_something_bpt = target.BreakpointCreateByLocation( "pass-to-base.cpp", self.do_something_line ) self.assertTrue(do_something_bpt, VALID_BREAKPOINT) first_call_bpt = target.BreakpointCreateByLocation( "pass-to-base.cpp", self.main_first_call_line ) self.assertTrue(first_call_bpt, VALID_BREAKPOINT) second_call_bpt = target.BreakpointCreateByLocation( "pass-to-base.cpp", self.main_second_call_line ) self.assertTrue(second_call_bpt, VALID_BREAKPOINT) # Now launch the process, and do not stop at the entry point. process = target.LaunchSimple(None, None, self.get_process_working_directory()) self.assertState(process.GetState(), lldb.eStateStopped, PROCESS_STOPPED) threads = lldbutil.get_threads_stopped_at_breakpoint(process, first_call_bpt) self.assertEqual(len(threads), 1) thread = threads[0] frame = thread.GetFrameAtIndex(0) # Now find the dynamic addresses of myB and otherB so we can compare them # with the dynamic values we get in doSomething: use_dynamic = lldb.eDynamicCanRunTarget no_dynamic = lldb.eNoDynamicValues myB = frame.FindVariable("myB", no_dynamic) self.assertTrue(myB) myB_loc = int(myB.GetLocation(), 16) otherB = frame.FindVariable("otherB", no_dynamic) self.assertTrue(otherB) otherB_loc = int(otherB.GetLocation(), 16) # Okay now run to doSomething: threads = lldbutil.continue_to_breakpoint(process, do_something_bpt) self.assertEqual(len(threads), 1) thread = threads[0] frame = thread.GetFrameAtIndex(0) # Get "this" using FindVariable: this_static = frame.FindVariable("this", no_dynamic) this_dynamic = frame.FindVariable("this", use_dynamic) self.examine_value_object_of_this_ptr(this_static, this_dynamic, myB_loc) # Now make sure that the "GetDynamicValue" works: # This doesn't work currently because we can't get dynamic values from # ConstResult objects. fetched_dynamic_value = this_static.GetDynamicValue(use_dynamic) self.examine_value_object_of_this_ptr( this_static, fetched_dynamic_value, myB_loc ) # And conversely that the GetDynamicValue() interface also works: fetched_static_value = this_dynamic.GetStaticValue() self.examine_value_object_of_this_ptr( fetched_static_value, this_dynamic, myB_loc ) # Get "this" using FindValue, make sure that works too: this_static = frame.FindValue( "this", lldb.eValueTypeVariableArgument, no_dynamic ) this_dynamic = frame.FindValue( "this", lldb.eValueTypeVariableArgument, use_dynamic ) self.examine_value_object_of_this_ptr(this_static, this_dynamic, myB_loc) # Get "this" using the EvaluateExpression: this_static = frame.EvaluateExpression("this", False) this_dynamic = frame.EvaluateExpression("this", True) self.examine_value_object_of_this_ptr(this_static, this_dynamic, myB_loc) # The "frame var" code uses another path to get into children, so let's # make sure that works as well: self.expect( "frame var -d run-target --ptr-depth=2 --show-types anotherA.m_client_A", "frame var finds its way into a child member", patterns=[r"\(B \*\)"], ) # Now make sure we also get it right for a reference as well: anotherA_static = frame.FindVariable("anotherA", False) self.assertTrue(anotherA_static) anotherA_static_addr = int(anotherA_static.GetValue(), 16) anotherA_dynamic = frame.FindVariable("anotherA", True) self.assertTrue(anotherA_dynamic) anotherA_dynamic_addr = int(anotherA_dynamic.GetValue(), 16) anotherA_dynamic_typename = anotherA_dynamic.GetTypeName() self.assertNotEqual(anotherA_dynamic_typename.find("B"), -1) self.assertLess(anotherA_dynamic_addr, anotherA_static_addr) anotherA_m_b_value_dynamic = anotherA_dynamic.GetChildMemberWithName( "m_b_value", True ) self.assertTrue(anotherA_m_b_value_dynamic) anotherA_m_b_val = int(anotherA_m_b_value_dynamic.GetValue(), 10) self.assertEqual(anotherA_m_b_val, 300) anotherA_m_b_value_static = anotherA_static.GetChildMemberWithName( "m_b_value", True ) self.assertFalse(anotherA_m_b_value_static) # Okay, now continue again, and when we hit the second breakpoint in # main threads = lldbutil.continue_to_breakpoint(process, second_call_bpt) self.assertEqual(len(threads), 1) thread = threads[0] frame = thread.GetFrameAtIndex(0) reallyA_value = frame.FindVariable("reallyA", False) self.assertTrue(reallyA_value) reallyA_loc = int(reallyA_value.GetLocation(), 16) # Continue to doSomething again, and make sure we get the right value for anotherA, # which this time around is just an "A". threads = lldbutil.continue_to_breakpoint(process, do_something_bpt) self.assertEqual(len(threads), 1) thread = threads[0] frame = thread.GetFrameAtIndex(0) anotherA_value = frame.FindVariable("anotherA", True) self.assertTrue(anotherA_value) anotherA_loc = int(anotherA_value.GetValue(), 16) self.assertEqual(anotherA_loc, reallyA_loc) self.assertEqual(anotherA_value.GetTypeName().find("B"), -1) # Finally do the same with a B in an anonymous namespace. threads = lldbutil.continue_to_breakpoint(process, do_something_bpt) self.assertEqual(len(threads), 1) thread = threads[0] frame = thread.GetFrameAtIndex(0) anotherA_value = frame.FindVariable("anotherA", use_dynamic) self.assertTrue(anotherA_value) self.assertIn("B", anotherA_value.GetTypeName()) anon_b_value = anotherA_value.GetChildMemberWithName("m_anon_b_value") self.assertTrue(anon_b_value) self.assertEqual(anon_b_value.GetValueAsSigned(), 47) def examine_value_object_of_this_ptr( self, this_static, this_dynamic, dynamic_location ): # Get "this" as its static value self.assertTrue(this_static) this_static_loc = int(this_static.GetValue(), 16) # Get "this" as its dynamic value self.assertTrue(this_dynamic) this_dynamic_typename = this_dynamic.GetTypeName() self.assertNotEqual(this_dynamic_typename.find("B"), -1) this_dynamic_loc = int(this_dynamic.GetValue(), 16) # Make sure we got the right address for "this" self.assertEqual(this_dynamic_loc, dynamic_location) # And that the static address is greater than the dynamic one self.assertGreater(this_static_loc, this_dynamic_loc) # Now read m_b_value which is only in the dynamic value: use_dynamic = lldb.eDynamicCanRunTarget no_dynamic = lldb.eNoDynamicValues this_dynamic_m_b_value = this_dynamic.GetChildMemberWithName( "m_b_value", use_dynamic ) self.assertTrue(this_dynamic_m_b_value) m_b_value = int(this_dynamic_m_b_value.GetValue(), 0) self.assertEqual(m_b_value, 10) # Make sure it is not in the static version this_static_m_b_value = this_static.GetChildMemberWithName( "m_b_value", no_dynamic ) self.assertFalse(this_static_m_b_value) # Okay, now let's make sure that we can get the dynamic type of a child # element: contained_auto_ptr = this_dynamic.GetChildMemberWithName( "m_client_A", use_dynamic ) self.assertTrue(contained_auto_ptr) contained_b = contained_auto_ptr.GetChildMemberWithName("_M_ptr", use_dynamic) if not contained_b: contained_b = contained_auto_ptr.GetChildMemberWithName( "__ptr_", use_dynamic ) self.assertTrue(contained_b) contained_b_static = contained_auto_ptr.GetChildMemberWithName( "_M_ptr", no_dynamic ) if not contained_b_static: contained_b_static = contained_auto_ptr.GetChildMemberWithName( "__ptr_", no_dynamic ) self.assertTrue(contained_b_static) contained_b_addr = int(contained_b.GetValue(), 16) contained_b_static_addr = int(contained_b_static.GetValue(), 16) self.assertLess(contained_b_addr, contained_b_static_addr) @no_debug_info_test @expectedFailureAll(oslist=["windows"], bugnumber="llvm.org/pr24663") def test_from_forward_decl(self): """Test fetching C++ dynamic values forward-declared types. It's imperative that this is a separate test so that we don't end up parsing a definition of A from somewhere else.""" self.build() lldbutil.run_to_name_breakpoint(self, "take_A") self.expect( "frame var -d run-target --ptr-depth=1 --show-types a", substrs=["(B *) a", "m_b_value = 10"], ) @no_debug_info_test @expectedFailureAll(oslist=["windows"], bugnumber="llvm.org/pr24663") @expectedFailureAll(archs=["arm$"]) # Minidump saving not implemented def test_from_core_file(self): """Test fetching C++ dynamic values from core files. Specifically, test that we can determine the dynamic type of the value if the core file does not contain the type vtable.""" self.build() lldbutil.run_to_name_breakpoint(self, "take_A") # Get the address of our object and its vtable a = self.frame().FindVariable("a") self.assertSuccess(a.GetError()) vtable = a.GetVTable() self.assertSuccess(vtable.GetError()) a = a.GetValueAsAddress() vtable = vtable.GetValueAsAddress() # Create a core file which will only contain the memory region # containing `a`. The object is on the stack, so this will automatically # include the stack of the main thread. core = self.getBuildArtifact("a.dmp") options = lldb.SBSaveCoreOptions() options.SetPluginName("minidump") options.SetStyle(lldb.eSaveCoreCustomOnly) options.SetOutputFile(lldb.SBFileSpec(core)) region = lldb.SBMemoryRegionInfo() self.assertSuccess(self.process().GetMemoryRegionInfo(a, region)) self.assertSuccess(options.AddMemoryRegionToSave(region)) # Save the core file and load it. self.assertSuccess(self.process().SaveCore(options)) self.process().Kill() error = lldb.SBError() self.target().LoadCore(core, error) self.assertSuccess(error) # Sanity check -- the process should be able to read the object but not # its vtable.. self.process().ReadPointerFromMemory(a, error) self.assertSuccess(error) self.process().ReadPointerFromMemory(vtable, error) self.assertTrue(error.Fail()) # .. but we should still be able to see the dynamic type by reading the # vtable from the executable file. self.expect( "frame var -d run-target --ptr-depth=1 --show-types a", substrs=["(B *) a", "m_b_value = 10"], )