From 5d70afd3a928e1185bcaf4b8fdbd32f42de5c745 Mon Sep 17 00:00:00 2001 From: Andreas Sandberg Date: Fri, 25 Jan 2019 11:40:53 +0000 Subject: [PATCH] python: Make meta class declarations Python 3 safe Python 2.x and Python 3 use different meta class syntax. Fix this by implementing meta classes using the add_metaclass decorator in the six Python library. Due to the way meta classes are implemented in six, MetaParamValue.__new__ seems to be called twice for some classes. This triggers an assertion which when param that checks that Param types have only been registered once. I have turned this assertion into a warning. The assertion was triggered in params.CheckedInt and params.Enum. It seems like the cause of the issue is that these classes have their own meta classes (CheckedIntType and MetaEnum) that inherit from MetaParamValue and a base class (ParamValue) that also inherits from MetaParamValue. Change-Id: I5dea08bf0558cfca57897a124cb131c78114e59e Signed-off-by: Andreas Sandberg Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/26083 Tested-by: kokoro Reviewed-by: Jason Lowe-Power Maintainer: Jason Lowe-Power --- src/python/m5/SimObject.py | 3 ++- src/python/m5/params.py | 21 +++++++++++---------- src/python/m5/util/code_formatter.py | 4 ++-- src/python/m5/util/pybind.py | 4 ++-- 4 files changed, 17 insertions(+), 15 deletions(-) diff --git a/src/python/m5/SimObject.py b/src/python/m5/SimObject.py index b76db5c31..32ac7d1dd 100644 --- a/src/python/m5/SimObject.py +++ b/src/python/m5/SimObject.py @@ -40,6 +40,7 @@ from __future__ import print_function from __future__ import absolute_import +from six import add_metaclass import six if six.PY3: long = int @@ -1073,10 +1074,10 @@ class SimObjectCliWrapper(object): # The SimObject class is the root of the special hierarchy. Most of # the code in this class deals with the configuration hierarchy itself # (parent/child node relationships). +@add_metaclass(MetaSimObject) class SimObject(object): # Specify metaclass. Any class inheriting from SimObject will # get this metaclass. - __metaclass__ = MetaSimObject type = 'SimObject' abstract = True diff --git a/src/python/m5/params.py b/src/python/m5/params.py index 3593f95bb..2ea614e95 100644 --- a/src/python/m5/params.py +++ b/src/python/m5/params.py @@ -55,6 +55,7 @@ ##################################################################### from __future__ import print_function +from six import add_metaclass import six if six.PY3: long = int @@ -87,15 +88,17 @@ allParams = {} class MetaParamValue(type): def __new__(mcls, name, bases, dct): cls = super(MetaParamValue, mcls).__new__(mcls, name, bases, dct) - assert name not in allParams + if name in allParams: + warn("%s already exists in allParams. This may be caused by the " \ + "Python 2.7 compatibility layer." % (name, )) allParams[name] = cls return cls # Dummy base class to identify types that are legitimate for SimObject # parameters. +@add_metaclass(MetaParamValue) class ParamValue(object): - __metaclass__ = MetaParamValue cmd_line_settable = False # Generate the code needed as a prerequisite for declaring a C++ @@ -233,8 +236,8 @@ class ParamDesc(object): # that the value is a vector (list) of the specified type instead of a # single value. +@add_metaclass(MetaParamValue) class VectorParamValue(list): - __metaclass__ = MetaParamValue def __setattr__(self, attr, value): raise AttributeError("Not allowed to set %s on '%s'" % \ (attr, type(self).__name__)) @@ -585,8 +588,8 @@ class CheckedIntType(MetaParamValue): # class is subclassed to generate parameter classes with specific # bounds. Initialization of the min and max bounds is done in the # metaclass CheckedIntType.__init__. +@add_metaclass(CheckedIntType) class CheckedInt(NumericParamValue): - __metaclass__ = CheckedIntType cmd_line_settable = True def _check(self): @@ -1294,7 +1297,6 @@ allEnums = {} # Metaclass for Enum types class MetaEnum(MetaParamValue): def __new__(mcls, name, bases, dict): - assert name not in allEnums cls = super(MetaEnum, mcls).__new__(mcls, name, bases, dict) allEnums[name] = cls @@ -1445,8 +1447,8 @@ module_init(py::module &m_internal) # Base class for enum types. +@add_metaclass(MetaEnum) class Enum(ParamValue): - __metaclass__ = MetaEnum vals = [] cmd_line_settable = True @@ -1499,8 +1501,8 @@ class Enum(ParamValue): return self.value # This param will generate a scoped c++ enum and its python bindings. +@add_metaclass(MetaEnum) class ScopedEnum(Enum): - __metaclass__ = MetaEnum vals = [] cmd_line_settable = True @@ -1787,8 +1789,8 @@ class MemoryBandwidth(float,ParamValue): # make_param_value() above that lets these be assigned where a # SimObject is required. # only one copy of a particular node +@add_metaclass(Singleton) class NullSimObject(object): - __metaclass__ = Singleton _name = 'Null' def __call__(cls): @@ -2155,9 +2157,8 @@ VectorSlavePort = VectorResponsePort # 'Fake' ParamDesc for Port references to assign to the _pdesc slot of # proxy objects (via set_param_desc()) so that proxy error messages # make sense. +@add_metaclass(Singleton) class PortParamDesc(object): - __metaclass__ = Singleton - ptype_str = 'Port' ptype = Port diff --git a/src/python/m5/util/code_formatter.py b/src/python/m5/util/code_formatter.py index 8d48d0f76..9870430d6 100644 --- a/src/python/m5/util/code_formatter.py +++ b/src/python/m5/util/code_formatter.py @@ -25,6 +25,7 @@ # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. from __future__ import print_function +from six import add_metaclass try: import builtins @@ -112,9 +113,8 @@ class code_formatter_meta(type): } cls.pattern = re.compile(pat, re.VERBOSE | re.DOTALL | re.MULTILINE) +@add_metaclass(code_formatter_meta) class code_formatter(object): - __metaclass__ = code_formatter_meta - delim = r'$' ident = r'[_A-z]\w*' pos = r'[0-9]+' diff --git a/src/python/m5/util/pybind.py b/src/python/m5/util/pybind.py index f16504428..18df3bb60 100644 --- a/src/python/m5/util/pybind.py +++ b/src/python/m5/util/pybind.py @@ -35,12 +35,12 @@ from __future__ import print_function from __future__ import absolute_import +from six import add_metaclass from abc import * +@add_metaclass(ABCMeta) class PyBindExport(object): - __metaclass__ = ABCMeta - @abstractmethod def export(self, code, cname): pass -- 2.30.2