[tools] add lldbinit

tools/lldb_commands.py

+# Copyright 2017 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.
+
+import lldb
+import re
+
+def jst(debugger, command, result, dict):

[Michael Achenbach, 2017/03/23 11:30:01]

nit: since command, result, dict are always unused, maybe just use *args and
maybe **kwargs, does that work? Also the var name dict is masking the built-in
dict.

+  """Print the current JavaScript stack trace"""
+  target = debugger.GetSelectedTarget()
+  process = target.GetProcess()
+  thread = process.GetSelectedThread()
+  frame = thread.GetSelectedFrame()
+  frame.EvaluateExpression("_v8_internal_Print_StackTrace();")
+  print("")
+
+def jss(debugger, command, result, dict):
+  """Skip the jitted stack on x64 to where we entered JS last"""
+  target = debugger.GetSelectedTarget()
+  process = target.GetProcess()
+  thread = process.GetSelectedThread()
+  frame = thread.GetSelectedFrame()
+  js_entry_sp = frame.EvaluateExpression("v8::internal::Isolate::Current()->thread_local_top()->js_entry_sp_;").GetValue()

[Michael Achenbach, 2017/03/23 11:30:01]

nit: 80 char line limit

+  sizeof_void = frame.EvaluateExpression("sizeof(void*)").GetValue()
+  rbp = frame.FindRegister("rbp")
+  rsp = frame.FindRegister("rsp")
+  pc = frame.FindRegister("pc")
+  rbp = js_entry_sp
+  rsp = js_entry_sp + 2 *sizeof_void
+  pc.value = js_entry_sp + sizeof_void
+
+def bta(debugger, command, result, dict):
+  """Print stack trace with assertion scopes"""
+  func_name_re = re.compile("([^(<]+)(?:\(.+\))?")
+  assert_re = re.compile("^v8::internal::Per\w+AssertType::(\w+)_ASSERT, (false|true)>")
+  target = debugger.GetSelectedTarget()
+  process = target.GetProcess()
+  thread = process.GetSelectedThread()
+  frame = thread.GetSelectedFrame()
+  for frame in thread:
+    functionSignature = frame.GetDisplayFunctionName()
+    if functionSignature is None:
+      continue
+    functionName = func_name_re.match(functionSignature)
+    line = frame.GetLineEntry().GetLine()
+    sourceFile = frame.GetLineEntry().GetFileSpec().GetFilename()
+    if line:
+      sourceFile = sourceFile + ":" + str(line)
+
+    if sourceFile is None:
+      sourceFile = ""
+    print("[%-2s] %-60s %-40s" % (frame.GetFrameID(),
+                                  functionName.group(1),
+                                  sourceFile))
+    match = assert_re.match(str(functionSignature))
+    if match:
+      if match.group(3) == "false":
+        prefix = "Disallow"
+        color = "\033[91m"
+      else:
+        prefix = "Allow"
+        color = "\033[92m"
+      print("%s -> %s %s (%s)\033[0m" % (color, prefix, match.group(2), match.group(1)))
+
+def __lldb_init_module (debugger, dict):
+  debugger.HandleCommand('command script add -f lldb_commands.jst jst')
+  debugger.HandleCommand('command script add -f lldb_commands.jss jss')
+  debugger.HandleCommand('command script add -f lldb_commands.bta bta')