encounter
/
dawn-cmake
mirror of https://github.com/encounter/dawn-cmake.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
dawn-cmake/src/tint/tint_lldb.py

398 lines
13 KiB
Python
Raw Blame History

# Copyright 2022 The Tint Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# Pretty printers for the Tint project.
#
# If using lldb from command line, add a line to your ~/.lldbinit to import the printers:
#
# command script import /path/to/dawn/src/tint/tint_lldb.py
#
#
# If using VS Code on MacOS with the Microsoft C/C++ extension, add the following to
# your launch.json (make sure you specify an absolute path to tint_lldb.py):
#
# "name": "Launch",
# "type": "cppdbg",
# "request": "launch",
# ...
# "setupCommands": [
# {
# "description": "Load tint pretty printers",
# "ignoreFailures": false,
# "text": "command script import /path/to/dawn/src/tint/tint_lldb.py,
# }
# ]
#
# If using VS Code with the CodeLLDB extension (https://github.com/vadimcn/vscode-lldb),
# add the following to your launch.json:
#
# "name": "Launch",
# "type": "lldb",
# "request": "launch",
# ...
# "initCommands": [
# "command script import /path/to/dawn/src/tint/tint_lldb.py"
# ]
# Based on pretty printers for:
# Rust: https://github.com/vadimcn/vscode-lldb/blob/master/formatters/rust.py
# Dlang: https://github.com/Pure-D/dlang-debug/blob/master/lldb_dlang.py
#
#
# Tips for debugging using VS Code:
#
# - Set a breakpoint where you can view the types you want to debug/write pretty printers for.
# - Debug Console: -exec command script import /path/to/dawn/src/tint/tint_lldb.py
# - You can re-run the above command to reload the printers after modifying the python script.
# - Useful docs:
# Formattesr: https://lldb.llvm.org/use/variable.html
# Python API: https://lldb.llvm.org/python_api.html
# Especially:
# SBType: https://lldb.llvm.org/python_api/lldb.SBType.html
# SBValue: https://lldb.llvm.org/python_api/lldb.SBValue.html
from __future__ import print_function, division
import sys
import logging
import re
import lldb
import types
if sys.version_info[0] == 2:
# python2-based LLDB accepts utf8-encoded ascii strings only.
def to_lldb_str(s): return s.encode(
'utf8', 'backslashreplace') if isinstance(s, unicode) else s
range = xrange
else:
to_lldb_str = str
string_encoding = "escape" # remove | unicode | escape
log = logging.getLogger(__name__)
module = sys.modules[__name__]
tint_category = None
def __lldb_init_module(debugger, dict):
global tint_category
tint_category = debugger.CreateCategory('tint')
tint_category.SetEnabled(True)
attach_synthetic_to_type(
UtilsSlicePrinter, r'^tint::utils::Slice<.+>$', True)
attach_synthetic_to_type(
UtilsVectorPrinter, r'^tint::utils::Vector<.+>$', True)
attach_synthetic_to_type(
UtilsVectorRefPrinter, r'^tint::utils::VectorRef<.+>$', True)
attach_synthetic_to_type(
UtilsHashsetPrinter, r'^tint::utils::Hashset<.+>$', True)
attach_synthetic_to_type(
UtilsHashmapPrinter, r'^tint::utils::Hashmap<.+>$', True)
def attach_synthetic_to_type(synth_class, type_name, is_regex=False):
global module, tint_category
synth = lldb.SBTypeSynthetic.CreateWithClassName(
__name__ + '.' + synth_class.__name__)
synth.SetOptions(lldb.eTypeOptionCascade)
ret = tint_category.AddTypeSynthetic(
lldb.SBTypeNameSpecifier(type_name, is_regex), synth)
log.debug('attaching synthetic %s to "%s", is_regex=%s -> %s',
synth_class.__name__, type_name, is_regex, ret)
def summary_fn(valobj, dict): return get_synth_summary(
synth_class, valobj, dict)
# LLDB accesses summary fn's by name, so we need to create a unique one.
summary_fn.__name__ = '_get_synth_summary_' + synth_class.__name__
setattr(module, summary_fn.__name__, summary_fn)
attach_summary_to_type(summary_fn, type_name, is_regex)
def attach_summary_to_type(summary_fn, type_name, is_regex=False):
global module, tint_category
summary = lldb.SBTypeSummary.CreateWithFunctionName(
__name__ + '.' + summary_fn.__name__)
summary.SetOptions(lldb.eTypeOptionCascade)
ret = tint_category.AddTypeSummary(
lldb.SBTypeNameSpecifier(type_name, is_regex), summary)
log.debug('attaching summary %s to "%s", is_regex=%s -> %s',
summary_fn.__name__, type_name, is_regex, ret)
def get_synth_summary(synth_class, valobj, dict):
''''
get_summary' is annoyingly not a part of the standard LLDB synth provider API.
This trick allows us to share data extraction logic between synth providers and their sibling summary providers.
'''
synth = synth_class(valobj.GetNonSyntheticValue(), dict)
synth.update()
summary = synth.get_summary()
return to_lldb_str(summary)
def member(valobj, *chain):
'''Performs chained GetChildMemberWithName lookups'''
for name in chain:
valobj = valobj.GetChildMemberWithName(name)
return valobj
class Printer(object):
'''Base class for Printers'''
def __init__(self, valobj, dict={}):
self.valobj = valobj
self.initialize()
def initialize(self):
return None
def update(self):
return False
def num_children(self):
return 0
def has_children(self):
return False
def get_child_at_index(self, index):
return None
def get_child_index(self, name):
return None
def get_summary(self):
return None
def member(self, *chain):
'''Performs chained GetChildMemberWithName lookups'''
return member(self.valobj, *chain)
def template_params(self):
'''Returns list of template params values (as strings)'''
type_name = self.valobj.GetTypeName()
params = []
level = 0
start = 0
for i, c in enumerate(type_name):
if c == '<':
level += 1
if level == 1:
start = i + 1
elif c == '>':
level -= 1
if level == 0:
params.append(type_name[start:i].strip())
elif c == ',' and level == 1:
params.append(type_name[start:i].strip())
start = i + 1
return params
def template_param_at(self, index):
'''Returns template param value at index (as string)'''
return self.template_params()[index]
class UtilsSlicePrinter(Printer):
'''Printer for tint::utils::Slice<T>'''
def initialize(self):
self.len = self.valobj.GetChildMemberWithName('len')
self.cap = self.valobj.GetChildMemberWithName('cap')
self.data = self.valobj.GetChildMemberWithName('data')
self.elem_type = self.data.GetType().GetPointeeType()
self.elem_size = self.elem_type.GetByteSize()
def get_summary(self):
return 'length={} capacity={}'.format(self.len.GetValueAsUnsigned(), self.cap.GetValueAsUnsigned())
def num_children(self):
# NOTE: VS Code on MacOS hangs if we try to expand something too large, so put an artificial limit
# until we can figure out how to know if this is a valid instance.
return min(self.len.GetValueAsUnsigned(), 256)
def has_children(self):
return True
def get_child_at_index(self, index):
try:
if not 0 <= index < self.num_children():
return None
# TODO: return self.value_at(index)
offset = index * self.elem_size
return self.data.CreateChildAtOffset('[%s]' % index, offset, self.elem_type)
except Exception as e:
log.error('%s', e)
raise
def value_at(self, index):
'''Returns array value at index'''
offset = index * self.elem_size
return self.data.CreateChildAtOffset('[%s]' % index, offset, self.elem_type)
class UtilsVectorPrinter(Printer):
'''Printer for tint::utils::Vector<T, N>'''
def initialize(self):
self.slice = self.member('impl_', 'slice')
self.slice_printer = UtilsSlicePrinter(self.slice)
self.fixed_size = int(self.template_param_at(1))
self.cap = self.slice_printer.member('cap')
def get_summary(self):
using_heap = self.cap.GetValueAsUnsigned() > self.fixed_size
return 'heap={} {}'.format(using_heap, self.slice_printer.get_summary())
def num_children(self):
return self.slice_printer.num_children()
def has_children(self):
return self.slice_printer.has_children()
def get_child_at_index(self, index):
return self.slice_printer.get_child_at_index(index)
def make_slice_printer(self):
return UtilsSlicePrinter(self.slice)
class UtilsVectorRefPrinter(Printer):
'''Printer for tint::utils::VectorRef<T>'''
def initialize(self):
self.slice = self.member('slice_')
self.slice_printer = UtilsSlicePrinter(self.slice)
self.can_move = self.member('can_move_')
def get_summary(self):
return 'can_move={} {}'.format(self.can_move.GetValue(), self.slice_printer.get_summary())
def num_children(self):
return self.slice_printer.num_children()
def has_children(self):
return self.slice_printer.has_children()
def get_child_at_index(self, index):
return self.slice_printer.get_child_at_index(index)
class UtilsHashsetPrinter(Printer):
'''Printer for Hashset<T, N, HASH, EQUAL>'''
def initialize(self):
self.slice = UtilsVectorPrinter(
self.member('slots_')).make_slice_printer()
self.try_read_std_optional_func = self.try_read_std_optional
def update(self):
self.valid_slots = []
for slot in range(0, self.slice.num_children()):
v = self.slice.value_at(slot)
if member(v, 'hash').GetValueAsUnsigned() != 0:
self.valid_slots.append(slot)
return False
def get_summary(self):
return 'length={}'.format(self.num_children())
def num_children(self):
return len(self.valid_slots)
def has_children(self):
return True
def get_child_at_index(self, index):
slot = self.valid_slots[index]
v = self.slice.value_at(slot)
value = member(v, 'value')
# value is a std::optional, let's try to extract its value for display
kvp = self.try_read_std_optional_func(slot, value)
if kvp is None:
# If we failed, just output the slot and value as is, which will use
# the default printer for std::optional.
kvp = slot, value
return kvp[1].CreateChildAtOffset('[{}]'.format(kvp[0]), 0, kvp[1].GetType())
def try_read_std_optional(self, slot, value):
try:
# libc++
v = value.EvaluateExpression('__val_')
if v.name is not None:
return slot, v
# libstdc++
v = value.EvaluateExpression('_M_payload._M_payload._M_value')
if v.name is not None:
return slot, v
return None
except:
return None
class UtilsHashmapPrinter(Printer):
'''Printer for Hashmap<K, V, N, HASH, EQUAL>'''
def initialize(self):
self.hash_set = UtilsHashsetPrinter(self.member('set_'))
# Replace the lookup function so we can extract the key and value out of the std::optionals in the Hashset
self.hash_set.try_read_std_optional_func = self.try_read_std_optional
def update(self):
self.hash_set.update()
def get_summary(self):
return self.hash_set.get_summary()
def num_children(self):
return self.hash_set.num_children()
def has_children(self):
return self.hash_set.has_children()
def get_child_at_index(self, index):
return self.hash_set.get_child_at_index(index)
def try_read_std_optional(self, slot, value):
try:
# libc++
val = value.EvaluateExpression('__val_')
k = val.EvaluateExpression('key')
v = val.EvaluateExpression('value')
if k.name is not None and v.name is not None:
return k.GetValue(), v
# libstdc++
val = value.EvaluateExpression('_M_payload._M_payload._M_value')
k = val.EvaluateExpression('key')
v = val.EvaluateExpression('value')
if k.name is not None and v.name is not None:
return k.GetValue(), v
except:
pass
# Failed, fall back on hash_set
return self.hash_set.try_read_std_optional(slot, value)
Reference in New Issue View Git Blame Copy Permalink