1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
# -*- coding: utf-8 -*-
#
# AWL simulator - CPU call stack
#
# Copyright 2012-2013 Michael Buesch <m@bues.ch>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
from awlsim.datatypes import *
from awlsim.blocks import *
from awlsim.parameters import *
from awlsim.objectcache import *
from awlsim.util import *
class CallStackElem(object):
"Call stack element"
localdataCache = ObjectCache(lambda cpu: ByteArray(cpu.specs.nrLocalbytes))
@classmethod
def resetCache(cls):
cls.localdataCache.reset()
def __init__(self, cpu, block, interfaceDB=None, parameters=()):
(self.cpu,
self.parenStack,
self.ip,
self.localdata,
self.block,
self.insns,
self.labels,
self.interfaceDB,
self.prevDbRegister,
self.prevDiRegister) = (
cpu,
[],
0,
self.localdataCache.get(cpu),
block,
block.insns,
block.labels,
interfaceDB,
cpu.dbRegister,
cpu.diRegister,
)
# Handle parameters
self.__outboundParams = []
if parameters:
blockInterface, interfaceDB, structInstance, callByRef_Types =\
block.interface, \
self.interfaceDB, \
self.interfaceDB.structInstance, \
BlockInterface.callByRef_Types
for param in parameters:
if param.isOutbound(blockInterface):
# This is an outbound parameter.
self.__outboundParams.append(param)
if param.isInbound(blockInterface):
# This is an inbound parameter.
# Transfer data into DBI
structField = param.getLvalueStructField(interfaceDB)
if structField.dataType.type in callByRef_Types:
data = param.rvalueOp.resolve().value.byteOffset
else:
data = cpu.fetch(param.rvalueOp)
structInstance.setFieldData(structField, data)
# Handle the exit from this code block.
def handleBlockExit(self):
# Transfer data out of DBI
if self.__outboundParams:
cpu, interfaceDB, structInstance =\
self.cpu, \
self.interfaceDB, \
self.interfaceDB.structInstance
for param in self.__outboundParams:
cpu.store(
param.rvalueOp,
structInstance.getFieldData(param.getLvalueStructField(interfaceDB))
)
# Assign the DB/DI registers
if self.block.interface.requiresInstanceDB:
# We are returning from an FB
self.cpu.dbRegister, self.cpu.diRegister = self.interfaceDB, self.prevDiRegister
else:
# We are returning from an FC
self.cpu.dbRegister, self.cpu.diRegister = self.prevDbRegister, self.prevDiRegister
def destroy(self):
# Only put it back into the cache, if the size didn't change.
if len(self.localdata) == self.cpu.specs.nrLocalbytes:
self.localdataCache.put(self.localdata)
def __repr__(self):
return str(self.block)
|
