static_inst.cc revision 7720:65d338a8dba4 
1/*
2 * Copyright (c) 2003-2005 The Regents of The University of Michigan
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 *
28 * Authors: Steve Reinhardt
29 *          Nathan Binkert
30 */
31
32#include <iostream>
33#include "cpu/static_inst.hh"
34#include "sim/core.hh"
35
36StaticInstPtr StaticInst::nullStaticInstPtr;
37
38// Define the decode cache hash map.
39StaticInst::DecodeCache StaticInst::decodeCache;
40StaticInst::AddrDecodeCache StaticInst::addrDecodeCache;
41StaticInst::cacheElement StaticInst::recentDecodes[2];
42
43using namespace std;
44
45StaticInst::~StaticInst()
46{
47    if (cachedDisassembly)
48        delete cachedDisassembly;
49}
50
51void
52StaticInst::dumpDecodeCacheStats()
53{
54    cerr << "Decode hash table stats @ " << curTick << ":" << endl;
55    cerr << "\tnum entries = " << decodeCache.size() << endl;
56    cerr << "\tnum buckets = " << decodeCache.bucket_count() << endl;
57    vector<int> hist(100, 0);
58    int max_hist = 0;
59    for (int i = 0; i < decodeCache.bucket_count(); ++i) {
60        int count = decodeCache.elems_in_bucket(i);
61        if (count > max_hist)
62            max_hist = count;
63        hist[count]++;
64    }
65    for (int i = 0; i <= max_hist; ++i) {
66        cerr << "\tbuckets of size " << i << " = " << hist[i] << endl;
67    }
68}
69
70bool
71StaticInst::hasBranchTarget(const TheISA::PCState &pc, ThreadContext *tc,
72                            TheISA::PCState &tgt) const
73{
74    if (isDirectCtrl()) {
75        tgt = branchTarget(pc);
76        return true;
77    }
78
79    if (isIndirectCtrl()) {
80        tgt = branchTarget(tc);
81        return true;
82    }
83
84    return false;
85}
86
87StaticInstPtr
88StaticInst::fetchMicroop(MicroPC upc) const
89{
90    panic("StaticInst::fetchMicroop() called on instruction "
91          "that is not microcoded.");
92}
93
94TheISA::PCState
95StaticInst::branchTarget(const TheISA::PCState &pc) const
96{
97    panic("StaticInst::branchTarget() called on instruction "
98          "that is not a PC-relative branch.");
99    M5_DUMMY_RETURN;
100}
101
102TheISA::PCState
103StaticInst::branchTarget(ThreadContext *tc) const
104{
105    panic("StaticInst::branchTarget() called on instruction "
106          "that is not an indirect branch.");
107    M5_DUMMY_RETURN;
108}
109
110const string &
111StaticInst::disassemble(Addr pc, const SymbolTable *symtab) const
112{
113    if (!cachedDisassembly)
114        cachedDisassembly = new string(generateDisassembly(pc, symtab));
115
116    return *cachedDisassembly;
117}
118