1# Copyright (c) 2013 Advanced Micro Devices, Inc.
2# Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
3# Copyright (c) 2009 The Hewlett-Packard Development Company
4# All rights reserved.
5#
6# Redistribution and use in source and binary forms, with or without
7# modification, are permitted provided that the following conditions are
8# met: redistributions of source code must retain the above copyright
9# notice, this list of conditions and the following disclaimer;
10# redistributions in binary form must reproduce the above copyright
11# notice, this list of conditions and the following disclaimer in the
12# documentation and/or other materials provided with the distribution;
13# neither the name of the copyright holders nor the names of its
14# contributors may be used to endorse or promote products derived from
15# this software without specific prior written permission.
16#
17# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29from slicc.ast.StatementAST import StatementAST
30from slicc.symbols import Var
31
32class PeekStatementAST(StatementAST):
33    def __init__(self, slicc, queue_name, type_ast, pairs, statements, method):
34        super(PeekStatementAST, self).__init__(slicc, pairs)
35
36        self.queue_name = queue_name
37        self.type_ast = type_ast
38        self.statements = statements
39        self.method = method
40
41    def __repr__(self):
42        return "[PeekStatementAST: %r queue_name: %r type: %r %r]" % \
43               (self.method, self.queue_name, self.type_ast, self.statements)
44
45    def generate(self, code, return_type):
46        self.symtab.pushFrame()
47
48        msg_type = self.type_ast.type
49
50        # Add new local var to symbol table
51        var = Var(self.symtab, "in_msg", self.location, msg_type, "(*in_msg_ptr)",
52                  self.pairs)
53        self.symtab.newSymbol(var)
54
55        # Check the queue type
56        self.queue_name.assertType("InPort")
57
58        # Declare the new "in_msg_ptr" variable
59        mtid = msg_type.c_ident
60        qcode = self.queue_name.var.code
61        code('''
62{
63    // Declare message
64    const $mtid* in_msg_ptr M5_VAR_USED;
65    in_msg_ptr = dynamic_cast<const $mtid *>(($qcode).${{self.method}}());
66    if (in_msg_ptr == NULL) {
67        // If the cast fails, this is the wrong inport (wrong message type).
68        // Throw an exception, and the caller will decide to either try a
69        // different inport or punt.
70        throw RejectException();
71    }
72''')
73
74        if "block_on" in self.pairs:
75            address_field = self.pairs['block_on']
76            code('''
77    if (m_is_blocking &&
78        (m_block_map.count(in_msg_ptr->m_$address_field) == 1) &&
79        (m_block_map[in_msg_ptr->m_$address_field] != &$qcode)) {
80            $qcode.delayHead(clockEdge(), cyclesToTicks(Cycles(1)));
81            continue;
82    }
83            ''')
84
85        if "wake_up" in self.pairs:
86            address_field = self.pairs['wake_up']
87            code('''
88    if (m_waiting_buffers.count(in_msg_ptr->m_$address_field) > 0) {
89        wakeUpBuffers(in_msg_ptr->m_$address_field);
90    }
91            ''')
92
93        # The other statements
94        self.statements.generate(code, return_type)
95        self.symtab.popFrame()
96        code("}")
97
98    def findResources(self, resources):
99        self.statements.findResources(resources)
100