1/*
2 * Copyright (c) 2004-2005 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: Nathan Binkert
29 */
30
31#include "arch/mips/stacktrace.hh"
32
33#include <string>
34
35#include "arch/mips/isa_traits.hh"
36#include "arch/mips/vtophys.hh"
37#include "base/bitfield.hh"
38#include "base/trace.hh"
39#include "cpu/base.hh"
40#include "cpu/thread_context.hh"
41#include "mem/fs_translating_port_proxy.hh"
42#include "sim/system.hh"
43
44using namespace MipsISA;
45
46ProcessInfo::ProcessInfo(ThreadContext *_tc) : tc(_tc)
47{}
48
49Addr
50ProcessInfo::task(Addr ksp) const
51{
52    Addr base = ksp & ~0x3fff;
53    if (base == ULL(0xfffffc0000000000))
54        return 0;
55
56    Addr tsk;
57
58    PortProxy &vp = tc->getVirtProxy();
59    tsk = vp.read<Addr>(base + task_off, GuestByteOrder);
60
61    return tsk;
62}
63
64int
65ProcessInfo::pid(Addr ksp) const
66{
67    Addr task = this->task(ksp);
68    if (!task)
69        return -1;
70
71    uint16_t pd;
72
73    PortProxy &vp = tc->getVirtProxy();
74    pd = vp.read<uint16_t>(task + pid_off, GuestByteOrder);
75
76    return pd;
77}
78
79std::string
80ProcessInfo::name(Addr ksp) const
81{
82    Addr task = this->task(ksp);
83    if (!task)
84        return "console";
85
86    char comm[256];
87    tc->getVirtProxy().readString(comm, task + name_off, sizeof(comm));
88    if (!comm[0])
89        return "startup";
90
91    return comm;
92}
93
94StackTrace::StackTrace()
95    : tc(0), stack(64)
96{
97}
98
99StackTrace::StackTrace(ThreadContext *_tc, const StaticInstPtr &inst)
100    : tc(0), stack(64)
101{
102    trace(_tc, inst);
103}
104
105StackTrace::~StackTrace()
106{
107}
108
109void
110StackTrace::trace(ThreadContext *_tc, bool is_call)
111{
112    tc = _tc;
113    bool usermode = 0;
114
115    if (usermode) {
116        stack.push_back(user);
117        return;
118    }
119}
120
121bool
122StackTrace::isEntry(Addr addr)
123{
124    return false;
125}
126
127bool
128StackTrace::decodeStack(MachInst inst, int &disp)
129{
130    // lda $sp, -disp($sp)
131    //
132    // Opcode<31:26> == 0x08
133    // RA<25:21> == 30
134    // RB<20:16> == 30
135    // Disp<15:0>
136    const MachInst mem_mask = 0xffff0000;
137    const MachInst lda_pattern = 0x23de0000;
138    const MachInst lda_disp_mask = 0x0000ffff;
139
140    // subq $sp, disp, $sp
141    // addq $sp, disp, $sp
142    //
143    // Opcode<31:26> == 0x10
144    // RA<25:21> == 30
145    // Lit<20:13>
146    // One<12> = 1
147    // Func<11:5> == 0x20 (addq)
148    // Func<11:5> == 0x29 (subq)
149    // RC<4:0> == 30
150    const MachInst intop_mask = 0xffe01fff;
151    const MachInst addq_pattern = 0x43c0141e;
152    const MachInst subq_pattern = 0x43c0153e;
153    const MachInst intop_disp_mask = 0x001fe000;
154    const int intop_disp_shift = 13;
155
156    if ((inst & mem_mask) == lda_pattern)
157        disp = -sext<16>(inst & lda_disp_mask);
158    else if ((inst & intop_mask) == addq_pattern)
159        disp = -int((inst & intop_disp_mask) >> intop_disp_shift);
160    else if ((inst & intop_mask) == subq_pattern)
161        disp = int((inst & intop_disp_mask) >> intop_disp_shift);
162    else
163        return false;
164
165    return true;
166}
167
168bool
169StackTrace::decodeSave(MachInst inst, int &reg, int &disp)
170{
171    // lda $stq, disp($sp)
172    //
173    // Opcode<31:26> == 0x08
174    // RA<25:21> == ?
175    // RB<20:16> == 30
176    // Disp<15:0>
177    const MachInst stq_mask = 0xfc1f0000;
178    const MachInst stq_pattern = 0xb41e0000;
179    const MachInst stq_disp_mask = 0x0000ffff;
180    const MachInst reg_mask = 0x03e00000;
181    const int reg_shift = 21;
182
183    if ((inst & stq_mask) == stq_pattern) {
184        reg = (inst & reg_mask) >> reg_shift;
185        disp = sext<16>(inst & stq_disp_mask);
186    } else {
187        return false;
188    }
189
190    return true;
191}
192
193/*
194 * Decode the function prologue for the function we're in, and note
195 * which registers are stored where, and how large the stack frame is.
196 */
197bool
198StackTrace::decodePrologue(Addr sp, Addr callpc, Addr func,
199                           int &size, Addr &ra)
200{
201    size = 0;
202    ra = 0;
203
204    for (Addr pc = func; pc < callpc; pc += sizeof(MachInst)) {
205        MachInst inst = tc->getVirtProxy().read<MachInst>(pc);
206
207        int reg, disp;
208        if (decodeStack(inst, disp)) {
209            if (size) {
210                return true;
211            }
212            size += disp;
213        } else if (decodeSave(inst, reg, disp)) {
214            if (!ra && reg == ReturnAddressReg) {
215                ra = tc->getVirtProxy().read<Addr>(sp + disp);
216                if (!ra) {
217                    return false;
218                }
219            }
220        }
221    }
222
223    return true;
224}
225
226#if TRACING_ON
227void
228StackTrace::dump()
229{
230    panic("Stack trace dump not implemented.\n");
231}
232#endif
233