InPortDeclAST.py revision 6999:f226c098c393 
1# Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
2# Copyright (c) 2009 The Hewlett-Packard Development Company
3# All rights reserved.
4#
5# Redistribution and use in source and binary forms, with or without
6# modification, are permitted provided that the following conditions are
7# met: redistributions of source code must retain the above copyright
8# notice, this list of conditions and the following disclaimer;
9# redistributions in binary form must reproduce the above copyright
10# notice, this list of conditions and the following disclaimer in the
11# documentation and/or other materials provided with the distribution;
12# neither the name of the copyright holders nor the names of its
13# contributors may be used to endorse or promote products derived from
14# this software without specific prior written permission.
15#
16# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28from slicc.ast.DeclAST import DeclAST
29from slicc.ast.TypeAST import TypeAST
30from slicc.symbols import Func, Type, Var
31
32class InPortDeclAST(DeclAST):
33    def __init__(self, slicc, ident, msg_type, var_expr, pairs, statements):
34        super(InPortDeclAST, self).__init__(slicc, pairs)
35
36        self.ident = ident
37        self.msg_type = msg_type
38        self.var_expr = var_expr
39        self.statements = statements
40        self.queue_type = TypeAST(slicc, "InPort")
41
42    def __repr__(self):
43        return "[InPortDecl: %s]" % self.ident
44
45    def generate(self):
46        symtab = self.symtab
47        void_type = symtab.find("void", Type)
48
49        code = self.slicc.codeFormatter()
50        queue_type = self.var_expr.generate(code)
51        if not queue_type.isInPort:
52            self.error("The inport queue's type must have the 'inport' " + \
53                       "attribute.  Type '%s' does not have this attribute.",
54                       queue_type)
55
56        type = self.queue_type.type
57        in_port = Var(self.symtab, self.ident, self.location, type, str(code),
58                      self.pairs)
59        symtab.newSymbol(in_port)
60
61        symtab.pushFrame()
62        param_types = []
63
64        # Check for Event
65        type = symtab.find("Event", Type)
66        if type is None:
67            self.error("in_port decls require 'Event' enumeration defined")
68        param_types.append(type)
69
70        # Check for Address
71        type = symtab.find("Address", Type)
72        if type is None:
73            self.error("in_port decls require 'Address' type to be defined")
74
75        param_types.append(type)
76
77        # Add the trigger method - FIXME, this is a bit dirty
78        pairs = { "external" : "yes" }
79        func = Func(self.symtab, "trigger", self.location, void_type,
80                    param_types, [], "", pairs, None)
81        symtab.newSymbol(func)
82
83        param_types = []
84        # Check for Event2
85        type = symtab.find("Event", Type)
86        if type is None:
87            self.error("in_port decls require 'Event' enumeration")
88
89        param_types.append(type)
90
91        # Check for Address2
92        type = symtab.find("Address", Type)
93        if type is None:
94            self.error("in_port decls require 'Address' type to be defined")
95
96        param_types.append(type)
97
98        # Add the doubleTrigger method - this hack supports tiggering
99        # two simulateous events
100        #
101        # The key is that the second transistion cannot fail because
102        # the first event cannot be undone therefore you must do some
103        # checks before calling double trigger to ensure that won't
104        # happen
105        func = Func(self.symtab, "doubleTrigger", self.location, void_type,
106                    param_types, [], "", pairs, None)
107        symtab.newSymbol(func)
108
109        # Add the continueProcessing method - this hack supports
110        # messages that don't trigger events
111        func = Func(self.symtab, "continueProcessing", self.location,
112                    void_type, [], [], "", pairs, None)
113        symtab.newSymbol(func)
114
115        if self.statements is not None:
116            rcode = self.slicc.codeFormatter()
117            rcode.indent()
118            rcode.indent()
119            self.statements.generate(rcode, None)
120            in_port["c_code_in_port"] = str(rcode)
121        symtab.popFrame()
122
123        # Add port to state machine
124        machine = symtab.state_machine
125        if machine is None:
126            self.error("InPort declaration not part of a machine.")
127
128        machine.addInPort(in_port)
129