v8/test/debugging/wasm/gdb-server/memory.py
Paolo Severini 74e9318689 Wasm debugging with LLDB: access Wasm engine state
This changelist makes the GDB-stub actually execute GDB-remote commands, by
accessing the Wasm engine state. More precisely:
- class GdbServer registers DebugDelegates that receive debug notifications when
  a new Wasm module is loaded, when execution suspends at a breakpoint or for an
  unhandled exception.
- Since the GDB-remote commands arrive on a separate thread, all
  queries from the debugger are transformed into Task objects, that are posted
  into a TaskRunner that runs in the Isolate thread.
- class WasmModuleDebug contains the logic to retrieve the value of globals, locals, memory ranges from the
  Wasm engine and to add/remove breakpoints.

Build with: v8_enable_wasm_gdb_remote_debugging = true
Run with: --wasm-gdb-remote
Test with: python tools\run-tests.py --outdir=out\debug_x64 debugging -j 1

Bug: chromium:1010467
Change-Id: I9703894620a027d3c920926db92e2ff809d84ab8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1941139
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Paolo Severini <paolosev@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#67412}
2020-04-28 01:02:32 +00:00

97 lines
3.5 KiB
Python

# Copyright 2020 the V8 project authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
# Flags: -expose-wasm --wasm-gdb-remote --wasm-pause-waiting-for-debugger test/debugging/wasm/gdb-server/test_files/test_memory.js
import struct
import sys
import unittest
import gdb_rsp
import test_files.test_memory as test_memory
# These are set up by Main().
COMMAND = None
class Tests(unittest.TestCase):
# Test that reading from an unreadable address gives a sensible error.
def CheckReadMemoryAtInvalidAddr(self, connection):
mem_addr = 0xffffffff
result = connection.RspRequest('m%x,%x' % (mem_addr, 1))
self.assertEquals(result, 'E02')
def RunToWasm(self, connection, breakpoint_addr):
# Set a breakpoint.
reply = connection.RspRequest('Z0,%x,1' % breakpoint_addr)
self.assertEqual(reply, 'OK')
# When we run the program, we should hit the breakpoint.
reply = connection.RspRequest('c')
gdb_rsp.AssertReplySignal(reply, gdb_rsp.SIGTRAP)
# Remove the breakpoint.
reply = connection.RspRequest('z0,%x,1' % breakpoint_addr)
self.assertEqual(reply, 'OK')
def test_reading_and_writing_memory(self):
with gdb_rsp.LaunchDebugStub(COMMAND) as connection:
module_load_addr = gdb_rsp.GetLoadedModuleAddress(connection)
breakpoint_addr = module_load_addr + test_memory.FUNC0_START_ADDR
self.RunToWasm(connection, breakpoint_addr)
self.CheckReadMemoryAtInvalidAddr(connection)
# Check reading code memory space.
expected_data = b'\0asm'
result = gdb_rsp.ReadCodeMemory(connection, module_load_addr, len(expected_data))
self.assertEqual(result, expected_data)
# Check reading instance memory at a valid range.
reply = connection.RspRequest('qWasmMem:0;%x;%x' % (32, 4))
value = struct.unpack('I', gdb_rsp.DecodeHex(reply))[0]
self.assertEquals(int(value), 0)
# Check reading instance memory at an invalid range.
reply = connection.RspRequest('qWasmMem:0;%x;%x' % (0xf0000000, 4))
self.assertEqual(reply, 'E03')
def test_wasm_global(self):
with gdb_rsp.LaunchDebugStub(COMMAND) as connection:
module_load_addr = gdb_rsp.GetLoadedModuleAddress(connection)
breakpoint_addr = module_load_addr + test_memory.FUNC0_START_ADDR
self.RunToWasm(connection, breakpoint_addr)
# Check reading valid global.
reply = connection.RspRequest('qWasmGlobal:0;0')
value = struct.unpack('I', gdb_rsp.DecodeHex(reply))[0]
self.assertEqual(0, value)
# Check reading invalid global.
reply = connection.RspRequest('qWasmGlobal:0;9')
self.assertEqual("E03", reply)
def test_wasm_call_stack(self):
with gdb_rsp.LaunchDebugStub(COMMAND) as connection:
module_load_addr = gdb_rsp.GetLoadedModuleAddress(connection)
breakpoint_addr = module_load_addr + test_memory.FUNC0_START_ADDR
self.RunToWasm(connection, breakpoint_addr)
reply = connection.RspRequest('qWasmCallStack')
stack = gdb_rsp.DecodeUInt64Array(reply)
assert(len(stack) > 2) # At least two Wasm frames, plus one or more JS frames.
self.assertEqual(stack[0], module_load_addr + test_memory.FUNC0_START_ADDR)
self.assertEqual(stack[1], module_load_addr + test_memory.FUNC1_RETURN_ADDR)
def Main():
index = sys.argv.index('--')
args = sys.argv[index + 1:]
# The remaining arguments go to unittest.main().
global COMMAND
COMMAND = args
unittest.main(argv=sys.argv[:index])
if __name__ == '__main__':
Main()