Files
clang-p2996/lldb/test/API/functionalities/reverse-execution/TestReverseContinueBreakpoints.py
Robert O'Callahan b7b9ccf449 [lldb] Implement basic support for reverse-continue (#112079)
This commit adds support for a
`SBProcess::ContinueInDirection()` API. A user-accessible command for
this will follow in a later commit.

This feature depends on a gdbserver implementation (e.g. `rr`) providing
support for the `bc` and `bs` packets. `lldb-server` does not support
those packets, and there is no plan to change that. For testing
purposes, this commit adds a Python implementation of *very limited*
record-and-reverse-execute functionality, implemented as a proxy between
lldb and lldb-server in `lldbreverse.py`. This should not (and in
practice cannot) be used for anything except testing.

The tests here are quite minimal but we test that simple breakpoints and
watchpoints work as expected during reverse execution, and that
conditional breakpoints and watchpoints work when the condition calls a
function that must be executed in the forward direction.
2025-01-22 08:37:17 +01:00

150 lines
6.2 KiB
Python

import lldb
import time
import unittest
from lldbsuite.test.lldbtest import *
from lldbsuite.test.decorators import *
from lldbsuite.test.gdbclientutils import *
from lldbsuite.test.lldbreverse import ReverseTestBase
from lldbsuite.test import lldbutil
class TestReverseContinueBreakpoints(ReverseTestBase):
def test_reverse_continue(self):
self.reverse_continue_internal(async_mode=False)
def test_reverse_continue_async(self):
self.reverse_continue_internal(async_mode=True)
def reverse_continue_internal(self, async_mode):
target, process, initial_threads = self.setup_recording(async_mode)
# Reverse-continue. We'll stop at the point where we started recording.
status = process.ContinueInDirection(lldb.eRunReverse)
self.assertSuccess(status)
self.expect_async_state_changes(
async_mode, process, [lldb.eStateRunning, lldb.eStateStopped]
)
self.expect(
"thread list",
STOPPED_DUE_TO_HISTORY_BOUNDARY,
substrs=["stopped", "stop reason = history boundary"],
)
# Continue forward normally until the target exits.
status = process.ContinueInDirection(lldb.eRunForward)
self.expect_async_state_changes(
async_mode, process, [lldb.eStateRunning, lldb.eStateExited]
)
self.assertSuccess(status)
self.assertState(process.GetState(), lldb.eStateExited)
self.assertEqual(process.GetExitStatus(), 0)
def test_reverse_continue_breakpoint(self):
self.reverse_continue_breakpoint_internal(async_mode=False)
def test_reverse_continue_breakpoint_async(self):
self.reverse_continue_breakpoint_internal(async_mode=True)
def reverse_continue_breakpoint_internal(self, async_mode):
target, process, initial_threads = self.setup_recording(async_mode)
# Reverse-continue to the function "trigger_breakpoint".
trigger_bkpt = target.BreakpointCreateByName("trigger_breakpoint", None)
status = process.ContinueInDirection(lldb.eRunReverse)
self.assertSuccess(status)
self.expect_async_state_changes(
async_mode, process, [lldb.eStateRunning, lldb.eStateStopped]
)
threads_now = lldbutil.get_threads_stopped_at_breakpoint(process, trigger_bkpt)
self.assertEqual(threads_now, initial_threads)
def test_reverse_continue_skip_breakpoint(self):
self.reverse_continue_skip_breakpoint_internal(async_mode=False)
def test_reverse_continue_skip_breakpoint_async(self):
self.reverse_continue_skip_breakpoint_internal(async_mode=True)
def reverse_continue_skip_breakpoint_internal(self, async_mode):
target, process, initial_threads = self.setup_recording(async_mode)
# Reverse-continue over a breakpoint at "trigger_breakpoint" whose
# condition is false (via function call).
# This tests that we continue in the correct direction after hitting
# the breakpoint.
trigger_bkpt = target.BreakpointCreateByName("trigger_breakpoint", None)
trigger_bkpt.SetCondition("false_condition()")
status = process.ContinueInDirection(lldb.eRunReverse)
self.expect_async_state_changes(
async_mode, process, [lldb.eStateRunning, lldb.eStateStopped]
)
self.assertSuccess(status)
self.expect(
"thread list",
STOPPED_DUE_TO_HISTORY_BOUNDARY,
substrs=["stopped", "stop reason = history boundary"],
)
def test_continue_preserves_direction(self):
self.continue_preserves_direction_internal(async_mode=False)
def test_continue_preserves_direction_asyhc(self):
self.continue_preserves_direction_internal(async_mode=True)
def continue_preserves_direction_internal(self, async_mode):
target, process, initial_threads = self.setup_recording(async_mode)
# Reverse-continue to the function "trigger_breakpoint".
trigger_bkpt = target.BreakpointCreateByName("trigger_breakpoint", None)
status = process.ContinueInDirection(lldb.eRunReverse)
self.assertSuccess(status)
self.expect_async_state_changes(
async_mode, process, [lldb.eStateRunning, lldb.eStateStopped]
)
# This should continue in reverse.
status = process.Continue()
self.expect_async_state_changes(
async_mode, process, [lldb.eStateRunning, lldb.eStateStopped]
)
self.assertSuccess(status)
self.expect(
"thread list",
STOPPED_DUE_TO_HISTORY_BOUNDARY,
substrs=["stopped", "stop reason = history boundary"],
)
def setup_recording(self, async_mode):
"""
Record execution of code between "start_recording" and "stop_recording" breakpoints.
Returns with the target stopped at "stop_recording", with recording disabled,
ready to reverse-execute.
"""
self.build()
target = self.dbg.CreateTarget("")
process = self.connect(target)
# Record execution from the start of the function "start_recording"
# to the start of the function "stop_recording". We want to keep the
# interval that we record as small as possible to minimize the run-time
# of our single-stepping recorder.
start_recording_bkpt = target.BreakpointCreateByName("start_recording", None)
initial_threads = lldbutil.continue_to_breakpoint(process, start_recording_bkpt)
self.assertEqual(len(initial_threads), 1)
target.BreakpointDelete(start_recording_bkpt.GetID())
self.start_recording()
stop_recording_bkpt = target.BreakpointCreateByName("stop_recording", None)
lldbutil.continue_to_breakpoint(process, stop_recording_bkpt)
target.BreakpointDelete(stop_recording_bkpt.GetID())
self.stop_recording()
self.dbg.SetAsync(async_mode)
self.expect_async_state_changes(async_mode, process, [lldb.eStateStopped])
return target, process, initial_threads
def expect_async_state_changes(self, async_mode, process, states):
if not async_mode:
return
listener = self.dbg.GetListener()
lldbutil.expect_state_changes(self, listener, process, states)