137 lines
4.7 KiB
Python
137 lines
4.7 KiB
Python
# MIT License
|
|
#
|
|
# Copyright (c) 2023 Neil Webber
|
|
#
|
|
# Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
# of this software and associated documentation files (the "Software"), to deal
|
|
# in the Software without restriction, including without limitation the rights
|
|
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
# copies of the Software, and to permit persons to whom the Software is
|
|
# furnished to do so, subject to the following conditions:
|
|
#
|
|
# The above copyright notice and this permission notice shall be included in
|
|
# all copies or substantial portions of the Software.
|
|
#
|
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
# SOFTWARE.
|
|
|
|
|
|
import collections
|
|
|
|
#
|
|
# BREAKPOINT FRAMEWORK
|
|
#
|
|
# Arguably this is more complex than necessary; it could have been
|
|
# (and, indeed, was originally) built into the pdp.run() method as a simple
|
|
# set of arguments for stepping N steps or stopping at a given PC and
|
|
# nothing fancier than that could be specified.
|
|
#
|
|
# However, this generalization now allows arbitrary breakpoint processing.
|
|
# Custom Breakpoint objects can contain state, and anything that can
|
|
# be implemented as a per-instruction-boundary test is now possible.
|
|
# The breakpoint objects can also store logs of relevant state information
|
|
# (see, for example, the Lookback mixin).
|
|
#
|
|
# CAUTION regarding breakpoint state data and object re-use. If a
|
|
# breakpoint object is created once but supplied to multiple pdp.run()
|
|
# method calls, it (obviously?) will carry its previous state forward.
|
|
# It is not initialized anew each call to pdp.run(). Thus, for example,
|
|
# if it is a "run N steps" breakpoint and has partially (or completely)
|
|
# counted down, the count does not start over with the second call.
|
|
# This may or may not be what was desired. Code accordingly. Note that
|
|
# run_steps() and run_until() create a new breakpoint object every time
|
|
# and avoid this issue that way.
|
|
#
|
|
|
|
|
|
class Breakpoint:
|
|
# the base Breakpoint class: a null breakpoint that never fires
|
|
def __call__(self, pdp):
|
|
return False
|
|
|
|
|
|
class StepsBreakpoint(Breakpoint):
|
|
def __init__(self, *args, steps, **kwargs):
|
|
super().__init__(*args, **kwargs)
|
|
self.steps = self.togo = steps
|
|
|
|
def __call__(self, pdp):
|
|
self.togo -= 1
|
|
return self.togo == 0
|
|
|
|
|
|
class PCBreakpoint(Breakpoint):
|
|
def __init__(self, *, stoppc, stopmode=None):
|
|
self.stoppc = stoppc
|
|
self.stopmode = stopmode
|
|
|
|
def __call__(self, pdp):
|
|
if pdp.r[pdp.PC] == self.stoppc:
|
|
if self.stopmode is None or pdp.psw_curmode == self.stopmode:
|
|
pdp.logger.info(f".run: breakpt at {oct(self.stoppc)}")
|
|
return True
|
|
return False
|
|
|
|
|
|
# Mixin to cause the breakpoint to fire only on the Nth occurrence.
|
|
# This must be added at the front of the subclass list
|
|
# FOR EXAMPLE:
|
|
# class NthPC(NthBreakpoint, PCBreakpoint):
|
|
# pass
|
|
#
|
|
|
|
class NthBreakpoint:
|
|
def __init__(self, nth, *args, **kwargs):
|
|
self.__nth = self.__count = nth
|
|
super().__init__(*args, **kwargs)
|
|
|
|
def __call__(self, pdp):
|
|
if super().__call__(pdp):
|
|
self.__count -= 1
|
|
return self.__count == 0
|
|
|
|
|
|
# Mixin to add state lookback to a given breakpoint.
|
|
# This must be added at the front of the subclass list
|
|
# FOR EXAMPLE:
|
|
# class StepsPlusLookback(Lookback, StepsBreakpoint)
|
|
# pass
|
|
#
|
|
# ALTERNATIVELY, can be used entirely by itself, and will provide
|
|
# a lookback if the run() loop terminates for any reason (e.g., a HALT).
|
|
#
|
|
class Lookback(Breakpoint):
|
|
|
|
def __init__(self, *args, lookbacks=100, **kwargs):
|
|
self.__backstates = collections.deque([], lookbacks)
|
|
super().__init__(*args, **kwargs)
|
|
|
|
def __call__(self, pdp):
|
|
self.__backstates.append(pdp.machinestate())
|
|
return super().__call__(pdp)
|
|
|
|
@property
|
|
def states(self):
|
|
return list(self.__backstates)
|
|
|
|
|
|
class MultiBreakpoint(Breakpoint):
|
|
# a breakpoint that fires if any of the contained breakpoints fire
|
|
|
|
def __init__(self, bp0, /, *bps, testall=True):
|
|
self.testall = testall
|
|
self.bkpts = [bp0] + list(bps)
|
|
|
|
def __call__(self, pdp):
|
|
stophere = False
|
|
for bp in self.bkpts:
|
|
if bp(pdp):
|
|
stophere = True
|
|
if not self.testall:
|
|
break
|
|
return stophere
|