gem5/src/mem/slicc/symbols/State.py
David Hashe ee0d414fa8 slicc: support for transitions with a wildcard next state
This patches adds support for transitions of the form:

transition(START, EVENTS, *) { ACTIONS }

This allows a machine to collapse states that differ only in the next state
transition to collapse into one, and can help shorten/simplfy some protocols
significantly.

When * is encountered as an end state of a transition, the next state is
determined by calling the machine-specific getNextState function. The next
state is determined before any actions of the transition execute, and
therefore the next state calculation cannot depend on any of the transition
actions.
2015-07-20 09:15:18 -05:00

43 lines
1.9 KiB
Python

# Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
# Copyright (c) 2009 The Hewlett-Packard Development Company
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
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# redistributions in binary form must reproduce the above copyright
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# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
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# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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from slicc.symbols.Symbol import Symbol
class State(Symbol):
def __repr__(self):
return "[State: %s]" % self.ident
def isWildcard(self):
return False
class WildcardState(State):
def __repr__(self):
return "[State: *]"
def isWildcard(self):
return True
__all__ = [ "State" ]