src/sim/process.cc

   1 /*
   2  * Copyright (c) 2014 Advanced Micro Devices, Inc.
   3  * Copyright (c) 2012 ARM Limited
   4  * All rights reserved
   5  *
   6  * The license below extends only to copyright in the software and shall
   7  * not be construed as granting a license to any other intellectual
   8  * property including but not limited to intellectual property relating
   9  * to a hardware implementation of the functionality of the software
  10  * licensed hereunder.  You may use the software subject to the license
  11  * terms below provided that you ensure that this notice is replicated
  12  * unmodified and in its entirety in all distributions of the software,
  13  * modified or unmodified, in source code or in binary form.
  14  *
  15  * Copyright (c) 2001-2005 The Regents of The University of Michigan
  16  * All rights reserved.
  17  *
  18  * Redistribution and use in source and binary forms, with or without
  19  * modification, are permitted provided that the following conditions are
  20  * met: redistributions of source code must retain the above copyright
  21  * notice, this list of conditions and the following disclaimer;
  22  * redistributions in binary form must reproduce the above copyright
  23  * notice, this list of conditions and the following disclaimer in the
  24  * documentation and/or other materials provided with the distribution;
  25  * neither the name of the copyright holders nor the names of its
  26  * contributors may be used to endorse or promote products derived from
  27  * this software without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  30  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  31  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  32  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  33  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  34  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  35  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  36  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  37  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  38  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  39  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  40  *
  41  * Authors: Nathan Binkert
  42  *          Steve Reinhardt
  43  *          Ali Saidi
  44  */
  45
  46 #include "sim/process.hh"
  47
  48 #include <fcntl.h>
  49 #include <unistd.h>
  50
  51 #include <array>
  52 #include <map>
  53 #include <string>
  54 #include <vector>
  55
  56 #include "base/intmath.hh"
  57 #include "base/loader/object_file.hh"
  58 #include "base/loader/symtab.hh"
  59 #include "base/statistics.hh"
  60 #include "config/the_isa.hh"
  61 #include "cpu/thread_context.hh"
  62 #include "mem/page_table.hh"
  63 #include "mem/se_translating_port_proxy.hh"
  64 #include "params/Process.hh"
  65 #include "sim/emul_driver.hh"
  66 #include "sim/syscall_desc.hh"
  67 #include "sim/system.hh"
  68
  69 #if THE_ISA == ALPHA_ISA
  70 #include "arch/alpha/linux/process.hh"
  71 #elif THE_ISA == SPARC_ISA
  72 #include "arch/sparc/linux/process.hh"
  73 #include "arch/sparc/solaris/process.hh"
  74 #elif THE_ISA == MIPS_ISA
  75 #include "arch/mips/linux/process.hh"
  76 #elif THE_ISA == ARM_ISA
  77 #include "arch/arm/linux/process.hh"
  78 #include "arch/arm/freebsd/process.hh"
  79 #elif THE_ISA == X86_ISA
  80 #include "arch/x86/linux/process.hh"
  81 #elif THE_ISA == POWER_ISA
  82 #include "arch/power/linux/process.hh"
  83 #elif THE_ISA == RISCV_ISA
  84 #include "arch/riscv/linux/process.hh"
  85 #else
  86 #error "THE_ISA not set"
  87 #endif
  88
  89
  90 using namespace std;
  91 using namespace TheISA;
  92
  93 // current number of allocated processes
  94 int num_processes = 0;
  95
  96 template<class IntType>
  97
  98 AuxVector<IntType>::AuxVector(IntType type, IntType val)
  99 {
 100     a_type = TheISA::htog(type);
 101     a_val = TheISA::htog(val);
 102 }
 103
 104 template struct AuxVector<uint32_t>;
 105 template struct AuxVector<uint64_t>;
 106
 107 static int
 108 openFile(const string& filename, int flags, mode_t mode)
 109 {
 110     int sim_fd = open(filename.c_str(), flags, mode);
 111     if (sim_fd != -1)
 112         return sim_fd;
 113     fatal("Unable to open %s with mode %O", filename, mode);
 114 }
 115
 116 static int
 117 openInputFile(const string &filename)
 118 {
 119     return openFile(filename, O_RDONLY, 0);
 120 }
 121
 122 static int
 123 openOutputFile(const string &filename)
 124 {
 125     return openFile(filename, O_WRONLY | O_CREAT | O_TRUNC, 0664);
 126 }
 127
 128 Process::Process(ProcessParams * params, ObjectFile * obj_file)
 129     : SimObject(params), system(params->system),
 130       brk_point(0), stack_base(0), stack_size(0), stack_min(0),
 131       max_stack_size(params->max_stack_size),
 132       next_thread_stack_base(0),
 133       useArchPT(params->useArchPT),
 134       kvmInSE(params->kvmInSE),
 135       pTable(useArchPT ?
 136         static_cast<PageTableBase *>(new ArchPageTable(name(), params->pid,
 137             system)) :
 138         static_cast<PageTableBase *>(new FuncPageTable(name(), params->pid))),
 139       initVirtMem(system->getSystemPort(), this,
 140                   SETranslatingPortProxy::Always),
 141       fd_array(make_shared<array<FDEntry, NUM_FDS>>()),
 142       imap {{"",       -1},
 143             {"cin",    STDIN_FILENO},
 144             {"stdin",  STDIN_FILENO}},
 145       oemap{{"",       -1},
 146             {"cout",   STDOUT_FILENO},
 147             {"stdout", STDOUT_FILENO},
 148             {"cerr",   STDERR_FILENO},
 149             {"stderr", STDERR_FILENO}},
 150       objFile(obj_file),
 151       argv(params->cmd), envp(params->env), cwd(params->cwd),
 152       executable(params->executable),
 153       _uid(params->uid), _euid(params->euid),
 154       _gid(params->gid), _egid(params->egid),
 155       _pid(params->pid), _ppid(params->ppid),
 156       drivers(params->drivers)
 157 {
 158     int sim_fd;
 159     std::map<string,int>::iterator it;
 160
 161     // Search through the input options and set fd if match is found;
 162     // otherwise, open an input file and seek to location.
 163     FDEntry *fde_stdin = getFDEntry(STDIN_FILENO);
 164     if ((it = imap.find(params->input)) != imap.end())
 165         sim_fd = it->second;
 166     else
 167         sim_fd = openInputFile(params->input);
 168     fde_stdin->set(sim_fd, params->input, O_RDONLY, -1, false);
 169
 170     // Search through the output/error options and set fd if match is found;
 171     // otherwise, open an output file and seek to location.
 172     FDEntry *fde_stdout = getFDEntry(STDOUT_FILENO);
 173     if ((it = oemap.find(params->output)) != oemap.end())
 174         sim_fd = it->second;
 175     else
 176         sim_fd = openOutputFile(params->output);
 177     fde_stdout->set(sim_fd, params->output, O_WRONLY | O_CREAT | O_TRUNC,
 178                     0664, false);
 179
 180     FDEntry *fde_stderr = getFDEntry(STDERR_FILENO);
 181     if (params->output == params->errout)
 182         // Reuse the same file descriptor if these match.
 183         sim_fd = fde_stdout->fd;
 184     else if ((it = oemap.find(params->errout)) != oemap.end())
 185         sim_fd = it->second;
 186     else
 187         sim_fd = openOutputFile(params->errout);
 188     fde_stderr->set(sim_fd, params->errout, O_WRONLY | O_CREAT | O_TRUNC,
 189                     0664, false);
 190
 191     mmap_end = 0;
 192     nxm_start = nxm_end = 0;
 193     // other parameters will be initialized when the program is loaded
 194
 195     // load up symbols, if any... these may be used for debugging or
 196     // profiling.
 197     if (!debugSymbolTable) {
 198         debugSymbolTable = new SymbolTable();
 199         if (!objFile->loadGlobalSymbols(debugSymbolTable) ||
 200             !objFile->loadLocalSymbols(debugSymbolTable) ||
 201             !objFile->loadWeakSymbols(debugSymbolTable)) {
 202             // didn't load any symbols
 203             delete debugSymbolTable;
 204             debugSymbolTable = NULL;
 205         }
 206     }
 207 }
 208
 209
 210 void
 211 Process::regStats()
 212 {
 213     SimObject::regStats();
 214
 215     using namespace Stats;
 216
 217     num_syscalls
 218         .name(name() + ".num_syscalls")
 219         .desc("Number of system calls")
 220         ;
 221 }
 222
 223 void
 224 Process::inheritFDArray(Process *p)
 225 {
 226     fd_array = p->fd_array;
 227 }
 228
 229 ThreadContext *
 230 Process::findFreeContext()
 231 {
 232     for (int id : contextIds) {
 233         ThreadContext *tc = system->getThreadContext(id);
 234         if (tc->status() == ThreadContext::Halted)
 235             return tc;
 236     }
 237     return NULL;
 238 }
 239
 240 void
 241 Process::initState()
 242 {
 243     if (contextIds.empty())
 244         fatal("Process %s is not associated with any HW contexts!\n", name());
 245
 246     // first thread context for this process... initialize & enable
 247     ThreadContext *tc = system->getThreadContext(contextIds[0]);
 248
 249     // mark this context as active so it will start ticking.
 250     tc->activate();
 251
 252     pTable->initState(tc);
 253 }
 254
 255 DrainState
 256 Process::drain()
 257 {
 258     findFileOffsets();
 259     return DrainState::Drained;
 260 }
 261
 262 int
 263 Process::allocFD(int sim_fd, const string& filename, int flags, int mode,
 264                  bool pipe)
 265 {
 266     for (int free_fd = 0; free_fd < fd_array->size(); free_fd++) {
 267         FDEntry *fde = getFDEntry(free_fd);
 268         if (fde->isFree()) {
 269             fde->set(sim_fd, filename, flags, mode, pipe);
 270             return free_fd;
 271         }
 272     }
 273
 274     fatal("Out of target file descriptors");
 275 }
 276
 277 void
 278 Process::resetFDEntry(int tgt_fd)
 279 {
 280     FDEntry *fde = getFDEntry(tgt_fd);
 281     assert(fde->fd > -1);
 282
 283     fde->reset();
 284 }
 285
 286 int
 287 Process::getSimFD(int tgt_fd)
 288 {
 289     FDEntry *entry = getFDEntry(tgt_fd);
 290     return entry ? entry->fd : -1;
 291 }
 292
 293 FDEntry *
 294 Process::getFDEntry(int tgt_fd)
 295 {
 296     assert(0 <= tgt_fd && tgt_fd < fd_array->size());
 297     return &(*fd_array)[tgt_fd];
 298 }
 299
 300 int
 301 Process::getTgtFD(int sim_fd)
 302 {
 303     for (int index = 0; index < fd_array->size(); index++)
 304         if ((*fd_array)[index].fd == sim_fd)
 305             return index;
 306     return -1;
 307 }
 308
 309 void
 310 Process::allocateMem(Addr vaddr, int64_t size, bool clobber)
 311 {
 312     int npages = divCeil(size, (int64_t)PageBytes);
 313     Addr paddr = system->allocPhysPages(npages);
 314     pTable->map(vaddr, paddr, size,
 315                 clobber ? PageTableBase::Clobber : PageTableBase::Zero);
 316 }
 317
 318 bool
 319 Process::fixupStackFault(Addr vaddr)
 320 {
 321     // Check if this is already on the stack and there's just no page there
 322     // yet.
 323     if (vaddr >= stack_min && vaddr < stack_base) {
 324         allocateMem(roundDown(vaddr, PageBytes), PageBytes);
 325         return true;
 326     }
 327
 328     // We've accessed the next page of the stack, so extend it to include
 329     // this address.
 330     if (vaddr < stack_min && vaddr >= stack_base - max_stack_size) {
 331         while (vaddr < stack_min) {
 332             stack_min -= TheISA::PageBytes;
 333             if (stack_base - stack_min > max_stack_size)
 334                 fatal("Maximum stack size exceeded\n");
 335             allocateMem(stack_min, TheISA::PageBytes);
 336             inform("Increasing stack size by one page.");
 337         };
 338         return true;
 339     }
 340     return false;
 341 }
 342
 343 void
 344 Process::fixFileOffsets()
 345 {
 346     auto seek = [] (FDEntry *fde)
 347     {
 348         if (lseek(fde->fd, fde->fileOffset, SEEK_SET) < 0)
 349             fatal("Unable to see to location in %s", fde->filename);
 350     };
 351
 352     std::map<string,int>::iterator it;
 353
 354     // Search through the input options and set fd if match is found;
 355     // otherwise, open an input file and seek to location.
 356     FDEntry *fde_stdin = getFDEntry(STDIN_FILENO);
 357
 358     // Check if user has specified a different input file, and if so, use it
 359     // instead of the file specified in the checkpoint. This also resets the
 360     // file offset from the checkpointed value
 361     string new_in = ((ProcessParams*)params())->input;
 362     if (new_in != fde_stdin->filename) {
 363         warn("Using new input file (%s) rather than checkpointed (%s)\n",
 364              new_in, fde_stdin->filename);
 365         fde_stdin->filename = new_in;
 366         fde_stdin->fileOffset = 0;
 367     }
 368
 369     if ((it = imap.find(fde_stdin->filename)) != imap.end()) {
 370         fde_stdin->fd = it->second;
 371     } else {
 372         fde_stdin->fd = openInputFile(fde_stdin->filename);
 373         seek(fde_stdin);
 374     }
 375
 376     // Search through the output/error options and set fd if match is found;
 377     // otherwise, open an output file and seek to location.
 378     FDEntry *fde_stdout = getFDEntry(STDOUT_FILENO);
 379
 380     // Check if user has specified a different output file, and if so, use it
 381     // instead of the file specified in the checkpoint. This also resets the
 382     // file offset from the checkpointed value
 383     string new_out = ((ProcessParams*)params())->output;
 384     if (new_out != fde_stdout->filename) {
 385         warn("Using new output file (%s) rather than checkpointed (%s)\n",
 386              new_out, fde_stdout->filename);
 387         fde_stdout->filename = new_out;
 388         fde_stdout->fileOffset = 0;
 389     }
 390
 391     if ((it = oemap.find(fde_stdout->filename)) != oemap.end()) {
 392         fde_stdout->fd = it->second;
 393     } else {
 394         fde_stdout->fd = openOutputFile(fde_stdout->filename);
 395         seek(fde_stdout);
 396     }
 397
 398     FDEntry *fde_stderr = getFDEntry(STDERR_FILENO);
 399
 400     // Check if user has specified a different error file, and if so, use it
 401     // instead of the file specified in the checkpoint. This also resets the
 402     // file offset from the checkpointed value
 403     string new_err = ((ProcessParams*)params())->errout;
 404     if (new_err != fde_stderr->filename) {
 405         warn("Using new error file (%s) rather than checkpointed (%s)\n",
 406              new_err, fde_stderr->filename);
 407         fde_stderr->filename = new_err;
 408         fde_stderr->fileOffset = 0;
 409     }
 410
 411     if (fde_stdout->filename == fde_stderr->filename) {
 412         // Reuse the same file descriptor if these match.
 413         fde_stderr->fd = fde_stdout->fd;
 414     } else if ((it = oemap.find(fde_stderr->filename)) != oemap.end()) {
 415         fde_stderr->fd = it->second;
 416     } else {
 417         fde_stderr->fd = openOutputFile(fde_stderr->filename);
 418         seek(fde_stderr);
 419     }
 420
 421     for (int tgt_fd = 3; tgt_fd < fd_array->size(); tgt_fd++) {
 422         FDEntry *fde = getFDEntry(tgt_fd);
 423         if (fde->fd == -1)
 424             continue;
 425
 426         if (fde->isPipe) {
 427             if (fde->filename == "PIPE-WRITE")
 428                 continue;
 429             assert(fde->filename == "PIPE-READ");
 430
 431             int fds[2];
 432             if (pipe(fds) < 0)
 433                 fatal("Unable to create new pipe");
 434
 435             fde->fd = fds[0];
 436
 437             FDEntry *fde_write = getFDEntry(fde->readPipeSource);
 438             assert(fde_write->filename == "PIPE-WRITE");
 439             fde_write->fd = fds[1];
 440         } else {
 441             fde->fd = openFile(fde->filename.c_str(), fde->flags, fde->mode);
 442             seek(fde);
 443         }
 444     }
 445 }
 446
 447 void
 448 Process::findFileOffsets()
 449 {
 450     for (auto& fde : *fd_array) {
 451         if (fde.fd != -1)
 452             fde.fileOffset = lseek(fde.fd, 0, SEEK_CUR);
 453     }
 454 }
 455
 456 void
 457 Process::setReadPipeSource(int read_pipe_fd, int source_fd)
 458 {
 459     FDEntry *fde = getFDEntry(read_pipe_fd);
 460     assert(source_fd >= -1);
 461     fde->readPipeSource = source_fd;
 462 }
 463
 464 void
 465 Process::serialize(CheckpointOut &cp) const
 466 {
 467     SERIALIZE_SCALAR(brk_point);
 468     SERIALIZE_SCALAR(stack_base);
 469     SERIALIZE_SCALAR(stack_size);
 470     SERIALIZE_SCALAR(stack_min);
 471     SERIALIZE_SCALAR(next_thread_stack_base);
 472     SERIALIZE_SCALAR(mmap_end);
 473     SERIALIZE_SCALAR(nxm_start);
 474     SERIALIZE_SCALAR(nxm_end);
 475     pTable->serialize(cp);
 476     for (int x = 0; x < fd_array->size(); x++) {
 477         (*fd_array)[x].serializeSection(cp, csprintf("FDEntry%d", x));
 478     }
 479
 480 }
 481
 482 void
 483 Process::unserialize(CheckpointIn &cp)
 484 {
 485     UNSERIALIZE_SCALAR(brk_point);
 486     UNSERIALIZE_SCALAR(stack_base);
 487     UNSERIALIZE_SCALAR(stack_size);
 488     UNSERIALIZE_SCALAR(stack_min);
 489     UNSERIALIZE_SCALAR(next_thread_stack_base);
 490     UNSERIALIZE_SCALAR(mmap_end);
 491     UNSERIALIZE_SCALAR(nxm_start);
 492     UNSERIALIZE_SCALAR(nxm_end);
 493     pTable->unserialize(cp);
 494     for (int x = 0; x < fd_array->size(); x++) {
 495         FDEntry *fde = getFDEntry(x);
 496         fde->unserializeSection(cp, csprintf("FDEntry%d", x));
 497     }
 498     fixFileOffsets();
 499     // The above returns a bool so that you could do something if you don't
 500     // find the param in the checkpoint if you wanted to, like set a default
 501     // but in this case we'll just stick with the instantiated value if not
 502     // found.
 503 }
 504
 505
 506 bool
 507 Process::map(Addr vaddr, Addr paddr, int size, bool cacheable)
 508 {
 509     pTable->map(vaddr, paddr, size,
 510                 cacheable ? PageTableBase::Zero : PageTableBase::Uncacheable);
 511     return true;
 512 }
 513
 514
 515 void
 516 Process::syscall(int64_t callnum, ThreadContext *tc)
 517 {
 518     num_syscalls++;
 519
 520     SyscallDesc *desc = getDesc(callnum);
 521     if (desc == NULL)
 522         fatal("Syscall %d out of range", callnum);
 523
 524     desc->doSyscall(callnum, this, tc);
 525 }
 526
 527 IntReg
 528 Process::getSyscallArg(ThreadContext *tc, int &i, int width)
 529 {
 530     return getSyscallArg(tc, i);
 531 }
 532
 533
 534 EmulatedDriver *
 535 Process::findDriver(std::string filename)
 536 {
 537     for (EmulatedDriver *d : drivers) {
 538         if (d->match(filename))
 539             return d;
 540     }
 541
 542     return NULL;
 543 }
 544
 545 void
 546 Process::updateBias()
 547 {
 548     ObjectFile *interp = objFile->getInterpreter();
 549
 550     if (!interp || !interp->relocatable())
 551         return;
 552
 553     // Determine how large the interpreters footprint will be in the process
 554     // address space.
 555     Addr interp_mapsize = roundUp(interp->mapSize(), TheISA::PageBytes);
 556
 557     // We are allocating the memory area; set the bias to the lowest address
 558     // in the allocated memory region.
 559     Addr ld_bias = mmapGrowsDown() ? mmap_end - interp_mapsize : mmap_end;
 560
 561     // Adjust the process mmap area to give the interpreter room; the real
 562     // execve system call would just invoke the kernel's internal mmap
 563     // functions to make these adjustments.
 564     mmap_end = mmapGrowsDown() ? ld_bias : mmap_end + interp_mapsize;
 565
 566     interp->updateBias(ld_bias);
 567 }
 568
 569
 570 ObjectFile *
 571 Process::getInterpreter()
 572 {
 573     return objFile->getInterpreter();
 574 }
 575
 576
 577 Addr
 578 Process::getBias()
 579 {
 580     ObjectFile *interp = getInterpreter();
 581
 582     return interp ? interp->bias() : objFile->bias();
 583 }
 584
 585
 586 Addr
 587 Process::getStartPC()
 588 {
 589     ObjectFile *interp = getInterpreter();
 590
 591     return interp ? interp->entryPoint() : objFile->entryPoint();
 592 }
 593
 594
 595 Process *
 596 ProcessParams::create()
 597 {
 598     Process *process = NULL;
 599
 600     // If not specified, set the executable parameter equal to the
 601     // simulated system's zeroth command line parameter
 602     if (executable == "") {
 603         executable = cmd[0];
 604     }
 605
 606     ObjectFile *obj_file = createObjectFile(executable);
 607     if (obj_file == NULL) {
 608         fatal("Can't load object file %s", executable);
 609     }
 610
 611 #if THE_ISA == ALPHA_ISA
 612     if (obj_file->getArch() != ObjectFile::Alpha)
 613         fatal("Object file architecture does not match compiled ISA (Alpha).");
 614
 615     switch (obj_file->getOpSys()) {
 616       case ObjectFile::UnknownOpSys:
 617         warn("Unknown operating system; assuming Linux.");
 618         // fall through
 619       case ObjectFile::Linux:
 620         process = new AlphaLinuxProcess(this, obj_file);
 621         break;
 622
 623       default:
 624         fatal("Unknown/unsupported operating system.");
 625     }
 626 #elif THE_ISA == SPARC_ISA
 627     if (obj_file->getArch() != ObjectFile::SPARC64 &&
 628         obj_file->getArch() != ObjectFile::SPARC32)
 629         fatal("Object file architecture does not match compiled ISA (SPARC).");
 630     switch (obj_file->getOpSys()) {
 631       case ObjectFile::UnknownOpSys:
 632         warn("Unknown operating system; assuming Linux.");
 633         // fall through
 634       case ObjectFile::Linux:
 635         if (obj_file->getArch() == ObjectFile::SPARC64) {
 636             process = new Sparc64LinuxProcess(this, obj_file);
 637         } else {
 638             process = new Sparc32LinuxProcess(this, obj_file);
 639         }
 640         break;
 641
 642
 643       case ObjectFile::Solaris:
 644         process = new SparcSolarisProcess(this, obj_file);
 645         break;
 646
 647       default:
 648         fatal("Unknown/unsupported operating system.");
 649     }
 650 #elif THE_ISA == X86_ISA
 651     if (obj_file->getArch() != ObjectFile::X86_64 &&
 652         obj_file->getArch() != ObjectFile::I386)
 653         fatal("Object file architecture does not match compiled ISA (x86).");
 654     switch (obj_file->getOpSys()) {
 655       case ObjectFile::UnknownOpSys:
 656         warn("Unknown operating system; assuming Linux.");
 657         // fall through
 658       case ObjectFile::Linux:
 659         if (obj_file->getArch() == ObjectFile::X86_64) {
 660             process = new X86_64LinuxProcess(this, obj_file);
 661         } else {
 662             process = new I386LinuxProcess(this, obj_file);
 663         }
 664         break;
 665
 666       default:
 667         fatal("Unknown/unsupported operating system.");
 668     }
 669 #elif THE_ISA == MIPS_ISA
 670     if (obj_file->getArch() != ObjectFile::Mips)
 671         fatal("Object file architecture does not match compiled ISA (MIPS).");
 672     switch (obj_file->getOpSys()) {
 673       case ObjectFile::UnknownOpSys:
 674         warn("Unknown operating system; assuming Linux.");
 675         // fall through
 676       case ObjectFile::Linux:
 677         process = new MipsLinuxProcess(this, obj_file);
 678         break;
 679
 680       default:
 681         fatal("Unknown/unsupported operating system.");
 682     }
 683 #elif THE_ISA == ARM_ISA
 684     ObjectFile::Arch arch = obj_file->getArch();
 685     if (arch != ObjectFile::Arm && arch != ObjectFile::Thumb &&
 686         arch != ObjectFile::Arm64)
 687         fatal("Object file architecture does not match compiled ISA (ARM).");
 688     switch (obj_file->getOpSys()) {
 689       case ObjectFile::UnknownOpSys:
 690         warn("Unknown operating system; assuming Linux.");
 691         // fall through
 692       case ObjectFile::Linux:
 693         if (arch == ObjectFile::Arm64) {
 694             process = new ArmLinuxProcess64(this, obj_file,
 695                                             obj_file->getArch());
 696         } else {
 697             process = new ArmLinuxProcess32(this, obj_file,
 698                                             obj_file->getArch());
 699         }
 700         break;
 701       case ObjectFile::FreeBSD:
 702         if (arch == ObjectFile::Arm64) {
 703             process = new ArmFreebsdProcess64(this, obj_file,
 704                                               obj_file->getArch());
 705         } else {
 706             process = new ArmFreebsdProcess32(this, obj_file,
 707                                               obj_file->getArch());
 708         }
 709         break;
 710       case ObjectFile::LinuxArmOABI:
 711         fatal("M5 does not support ARM OABI binaries. Please recompile with an"
 712               " EABI compiler.");
 713       default:
 714         fatal("Unknown/unsupported operating system.");
 715     }
 716 #elif THE_ISA == POWER_ISA
 717     if (obj_file->getArch() != ObjectFile::Power)
 718         fatal("Object file architecture does not match compiled ISA (Power).");
 719     switch (obj_file->getOpSys()) {
 720       case ObjectFile::UnknownOpSys:
 721         warn("Unknown operating system; assuming Linux.");
 722         // fall through
 723       case ObjectFile::Linux:
 724         process = new PowerLinuxProcess(this, obj_file);
 725         break;
 726
 727       default:
 728         fatal("Unknown/unsupported operating system.");
 729     }
 730 #elif THE_ISA == RISCV_ISA
 731     if (obj_file->getArch() != ObjectFile::Riscv)
 732         fatal("Object file architecture does not match compiled ISA (RISCV).");
 733     switch (obj_file->getOpSys()) {
 734       case ObjectFile::UnknownOpSys:
 735         warn("Unknown operating system; assuming Linux.");
 736         // fall through
 737       case ObjectFile::Linux:
 738         process = new RiscvLinuxProcess(this, obj_file);
 739         break;
 740       default:
 741         fatal("Unknown/unsupported operating system.");
 742     }
 743 #else
 744 #error "THE_ISA not set"
 745 #endif
 746
 747     if (process == NULL)
 748         fatal("Unknown error creating process object.");
 749     return process;
 750 }