src/arch/mips/stacktrace.cc

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