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[glibc.git] / elf / sprof.c

/* Read and display shared object profiling data.
   Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <argp.h>
#include <dlfcn.h>
#include <elf.h>
#include <error.h>
#include <fcntl.h>
#include <inttypes.h>
#include <libintl.h>
#include <locale.h>
#include <obstack.h>
#include <search.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ldsodefs.h>
#include <sys/gmon.h>
#include <sys/gmon_out.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <sys/stat.h>

/* Get libc version number.  */
#include "../version.h"

#define PACKAGE _libc_intl_domainname


#include <endian.h>
#if BYTE_ORDER == BIG_ENDIAN
#define byteorder ELFDATA2MSB
#define byteorder_name "big-endian"
#elif BYTE_ORDER == LITTLE_ENDIAN
#define byteorder ELFDATA2LSB
#define byteorder_name "little-endian"
#else
#error "Unknown BYTE_ORDER " BYTE_ORDER
#define byteorder ELFDATANONE
#endif


extern int __profile_frequency (void);

/* Name and version of program.  */
static void print_version (FILE *stream, struct argp_state *state);
void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version;

#define OPT_TEST        1

/* Definitions of arguments for argp functions.  */
static const struct argp_option options[] =
{
  { NULL, 0, NULL, 0, N_("Output selection:") },
  { "call-pairs", 'c', NULL, 0,
    N_("print list of count paths and their number of use") },
  { "flat-profile", 'p', NULL, 0,
    N_("generate flat profile with counts and ticks") },
  { "graph", 'q', NULL, 0, N_("generate call graph") },

  { "test", OPT_TEST, NULL, OPTION_HIDDEN, NULL },
  { NULL, 0, NULL, 0, NULL }
};

/* Short description of program.  */
static const char doc[] = N_("Read and display shared object profiling data");

/* Strings for arguments in help texts.  */
static const char args_doc[] = N_("SHOBJ [PROFDATA]");

/* Prototype for option handler.  */
static error_t parse_opt (int key, char *arg, struct argp_state *state);

/* Data structure to communicate with argp functions.  */
static struct argp argp =
{
  options, parse_opt, args_doc, doc, NULL, NULL
};


/* Operation modes.  */
static enum
{
  NONE = 0,
  FLAT_MODE = 1 << 0,
  CALL_GRAPH_MODE = 1 << 1,
  CALL_PAIRS = 1 << 2,

  DEFAULT_MODE = FLAT_MODE | CALL_GRAPH_MODE
} mode;

/* If nonzero the total number of invocations of a function is emitted.  */
int count_total;

/* Nozero for testing.  */
int do_test;

/* Strcuture describing calls.  */
struct here_fromstruct
{
  struct here_cg_arc_record volatile *here;
  uint16_t link;
};

/* We define a special type to address the elements of the arc table.
   This is basically the `gmon_cg_arc_record' format but it includes
   the room for the tag and it uses real types.  */
struct here_cg_arc_record
{
  uintptr_t from_pc;
  uintptr_t self_pc;
  uint32_t count;
} __attribute__ ((packed));


struct known_symbol;
struct arc_list
{
  size_t idx;
  uintmax_t count;

  struct arc_list *next;
};

static struct obstack ob_list;


struct known_symbol
{
  const char *name;
  uintptr_t addr;
  size_t size;

  uintmax_t ticks;
  uintmax_t calls;

  struct arc_list *froms;
  struct arc_list *tos;
};


struct shobj
{
  const char *name;             /* User-provided name.  */

  struct link_map *map;
  const char *dynstrtab;        /* Dynamic string table of shared object.  */
  const char *soname;           /* Soname of shared object.  */

  uintptr_t lowpc;
  uintptr_t highpc;
  unsigned long int kcountsize;
  size_t expected_size;         /* Expected size of profiling file.  */
  size_t tossize;
  size_t fromssize;
  size_t fromlimit;
  unsigned int hashfraction;
  int s_scale;

  void *symbol_map;
  size_t symbol_mapsize;
  const ElfW(Sym) *symtab;
  size_t symtab_size;
  const char *strtab;

  struct obstack ob_str;
  struct obstack ob_sym;
};


struct profdata
{
  void *addr;
  off_t size;

  char *hist;
  struct gmon_hist_hdr *hist_hdr;
  uint16_t *kcount;
  uint32_t narcs;               /* Number of arcs in toset.  */
  struct here_cg_arc_record *data;
  uint16_t *tos;
  struct here_fromstruct *froms;
};

/* Search tree for symbols.  */
void *symroot;
static struct known_symbol **sortsym;
static size_t symidx;
static uintmax_t total_ticks;

/* Prototypes for local functions.  */
static struct shobj *load_shobj (const char *name);
static void unload_shobj (struct shobj *shobj);
static struct profdata *load_profdata (const char *name, struct shobj *shobj);
static void unload_profdata (struct profdata *profdata);
static void count_total_ticks (struct shobj *shobj, struct profdata *profdata);
static void count_calls (struct shobj *shobj, struct profdata *profdata);
static void read_symbols (struct shobj *shobj);
static void add_arcs (struct profdata *profdata);
static void generate_flat_profile (struct profdata *profdata);
static void generate_call_graph (struct profdata *profdata);
static void generate_call_pair_list (struct profdata *profdata);


int
main (int argc, char *argv[])
{
  const char *shobj;
  const char *profdata;
  struct shobj *shobj_handle;
  struct profdata *profdata_handle;
  int remaining;

  setlocale (LC_ALL, "");

  /* Initialize the message catalog.  */
  textdomain (_libc_intl_domainname);

  /* Parse and process arguments.  */
  argp_parse (&argp, argc, argv, 0, &remaining, NULL);

  if (argc - remaining == 0 || argc - remaining > 2)
    {
      /* We need exactly two non-option parameter.  */
      argp_help (&argp, stdout, ARGP_HELP_SEE | ARGP_HELP_EXIT_ERR,
                 program_invocation_short_name);
      exit (1);
    }

  /* Get parameters.  */
  shobj = argv[remaining];
  if (argc - remaining == 2)
    profdata = argv[remaining + 1];
  else
    /* No filename for the profiling data given.  We will determine it
       from the soname of the shobj, later.  */
    profdata = NULL;

  /* First see whether we can load the shared object.  */
  shobj_handle = load_shobj (shobj);
  if (shobj_handle == NULL)
    exit (1);

  /* We can now determine the filename for the profiling data, if
     nececessary.  */
  if (profdata == NULL)
    {
      char *newp;

      if (shobj_handle->soname == NULL)
        {
          unload_shobj (shobj_handle);

          error (EXIT_FAILURE, 0, _("\
no filename for profiling data given and shared object `%s' has no soname"),
                 shobj);
        }

      newp = (char *) alloca (strlen (shobj_handle->soname)
                              + sizeof ".profile");
      stpcpy (stpcpy (newp, shobj_handle->soname), ".profile");
      profdata = newp;
    }

  /* Now see whether the profiling data file matches the given object.   */
  profdata_handle = load_profdata (profdata, shobj_handle);
  if (profdata_handle == NULL)
    {
      unload_shobj (shobj_handle);

      exit (1);
    }

  read_symbols (shobj_handle);

  /* Count the ticks.  */
  count_total_ticks (shobj_handle, profdata_handle);

  /* Count the calls.  */
  count_calls (shobj_handle, profdata_handle);

  /* Add the arc information.  */
  add_arcs (profdata_handle);

  /* If no mode is specified fall back to the default mode.  */
  if (mode == NONE)
    mode = DEFAULT_MODE;

  /* Do some work.  */
  if (mode & FLAT_MODE)
    generate_flat_profile (profdata_handle);

  if (mode & CALL_GRAPH_MODE)
    generate_call_graph (profdata_handle);

  if (mode & CALL_PAIRS)
    generate_call_pair_list (profdata_handle);

  /* Free the resources.  */
  unload_shobj (shobj_handle);
  unload_profdata (profdata_handle);

  return 0;
}


/* Handle program arguments.  */
static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
  switch (key)
    {
    case 'c':
      mode |= CALL_PAIRS;
      break;
    case 'p':
      mode |= FLAT_MODE;
      break;
    case 'q':
      mode |= CALL_GRAPH_MODE;
      break;
    case OPT_TEST:
      do_test = 1;
      break;
    default:
      return ARGP_ERR_UNKNOWN;
    }
  return 0;
}


/* Print the version information.  */
static void
print_version (FILE *stream, struct argp_state *state)
{
  fprintf (stream, "sprof (GNU %s) %s\n", PACKAGE, VERSION);
  fprintf (stream, gettext ("\
Copyright (C) %s Free Software Foundation, Inc.\n\
This is free software; see the source for copying conditions.  There is NO\n\
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\
"),
           "1999");
  fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper");
}


/* Note that we must not use `dlopen' etc.  The shobj object must not
   be loaded for use.  */
static struct shobj *
load_shobj (const char *name)
{
  struct link_map *map = NULL;
  struct shobj *result;
  ElfW(Addr) mapstart = ~((ElfW(Addr)) 0);
  ElfW(Addr) mapend = 0;
  const ElfW(Phdr) *ph;
  size_t textsize;
  unsigned int log_hashfraction;
  ElfW(Ehdr) *ehdr;
  int fd;
  ElfW(Shdr) *shdr;
  void *ptr;
  size_t pagesize = getpagesize ();
  const char *shstrtab;
  int idx;
  ElfW(Shdr) *symtab_entry;

  /* Since we use dlopen() we must be prepared to work around the sometimes
     strange lookup rules for the shared objects.  If we have a file foo.so
     in the current directory and the user specfies foo.so on the command
     line (without specifying a directory) we should load the file in the
     current directory even if a normal dlopen() call would read the other
     file.  We do this by adding a directory portion to the name.  */
  if (strchr (name, '/') == NULL)
    {
      char *load_name = (char *) alloca (strlen (name) + 3);
      stpcpy (stpcpy (load_name, "./"), name);

      map = (struct link_map *) dlopen (load_name, RTLD_LAZY);
    }
  if (map == NULL)
    {
      map = (struct link_map *) dlopen (name, RTLD_LAZY);
      if (map == NULL)
        {
          error (0, errno, _("failed to load shared object `%s'"), name);
          return NULL;
        }
    }

  /* Prepare the result.  */
  result = (struct shobj *) calloc (1, sizeof (struct shobj));
  if (result == NULL)
    {
      error (0, errno, _("cannot create internal descriptors"));
      dlclose (map);
      return NULL;
    }
  result->name = name;
  result->map = map;

  /* Compute the size of the sections which contain program code.
     This must match the code in dl-profile.c (_dl_start_profile).  */
  for (ph = map->l_phdr; ph < &map->l_phdr[map->l_phnum]; ++ph)
    if (ph->p_type == PT_LOAD && (ph->p_flags & PF_X))
      {
        ElfW(Addr) start = (ph->p_vaddr & ~(pagesize - 1));
        ElfW(Addr) end = ((ph->p_vaddr + ph->p_memsz + pagesize - 1)
                          & ~(pagesize - 1));

        if (start < mapstart)
          mapstart = start;
        if (end > mapend)
          mapend = end;
      }

  result->lowpc = ROUNDDOWN ((uintptr_t) (mapstart + map->l_addr),
                             HISTFRACTION * sizeof (HISTCOUNTER));
  result->highpc = ROUNDUP ((uintptr_t) (mapend + map->l_addr),
                            HISTFRACTION * sizeof (HISTCOUNTER));
  if (do_test)
    printf ("load addr: %0#*" PRIxPTR "\n"
            "lower bound PC: %0#*" PRIxPTR "\n"
            "upper bound PC: %0#*" PRIxPTR "\n",
            __ELF_NATIVE_CLASS == 32 ? 10 : 18, map->l_addr,
            __ELF_NATIVE_CLASS == 32 ? 10 : 18, result->lowpc,
            __ELF_NATIVE_CLASS == 32 ? 10 : 18, result->highpc);

  textsize = result->highpc - result->lowpc;
  result->kcountsize = textsize / HISTFRACTION;
  result->hashfraction = HASHFRACTION;
  if ((HASHFRACTION & (HASHFRACTION - 1)) == 0)
    /* If HASHFRACTION is a power of two, mcount can use shifting
       instead of integer division.  Precompute shift amount.  */
    log_hashfraction = __builtin_ffs (result->hashfraction
                                      * sizeof (struct here_fromstruct)) - 1;
  else
    log_hashfraction = -1;
  if (do_test)
    printf ("hashfraction = %d\ndivider = %Zu\n",
            result->hashfraction,
            result->hashfraction * sizeof (struct here_fromstruct));
  result->tossize = textsize / HASHFRACTION;
  result->fromlimit = textsize * ARCDENSITY / 100;
  if (result->fromlimit < MINARCS)
    result->fromlimit = MINARCS;
  if (result->fromlimit > MAXARCS)
    result->fromlimit = MAXARCS;
  result->fromssize = result->fromlimit * sizeof (struct here_fromstruct);

  result->expected_size = (sizeof (struct gmon_hdr)
                           + 4 + sizeof (struct gmon_hist_hdr)
                           + result->kcountsize
                           + 4 + 4
                           + (result->fromssize
                              * sizeof (struct here_cg_arc_record)));

  if (do_test)
    printf ("expected size: %Zd\n", result->expected_size);

#define SCALE_1_TO_1    0x10000L

  if (result->kcountsize < result->highpc - result->lowpc)
    {
      size_t range = result->highpc - result->lowpc;
      size_t quot = range / result->kcountsize;

      if (quot >= SCALE_1_TO_1)
        result->s_scale = 1;
      else if (quot >= SCALE_1_TO_1 / 256)
        result->s_scale = SCALE_1_TO_1 / quot;
      else if (range > ULONG_MAX / 256)
        result->s_scale = ((SCALE_1_TO_1 * 256)
                           / (range / (result->kcountsize / 256)));
      else
        result->s_scale = ((SCALE_1_TO_1 * 256)
                           / ((range * 256) / result->kcountsize));
    }
  else
    result->s_scale = SCALE_1_TO_1;

  if (do_test)
    printf ("s_scale: %d\n", result->s_scale);

  /* Determine the dynamic string table.  */
  if (map->l_info[DT_STRTAB] == NULL)
    result->dynstrtab = NULL;
  else
    result->dynstrtab = (const char *) (map->l_addr
                                        + map->l_info[DT_STRTAB]->d_un.d_ptr);
  if (do_test)
    printf ("string table: %p\n", result->dynstrtab);

  /* Determine the soname.  */
  if (map->l_info[DT_SONAME] == NULL)
    result->soname = NULL;
  else
    result->soname = result->dynstrtab + map->l_info[DT_SONAME]->d_un.d_val;
  if (do_test)
    printf ("soname: %s\n", result->soname);

  /* Now we have to load the symbol table.

     First load the section header table.  */
  ehdr = (ElfW(Ehdr) *) map->l_addr;

  /* Make sure we are on the right party.  */
  if (ehdr->e_shentsize != sizeof (ElfW(Shdr)))
    abort ();

  /* And we need the shared object file descriptor again.  */
  fd = open (map->l_name, O_RDONLY);
  if (fd == -1)
    /* Dooh, this really shouldn't happen.  We know the file is available.  */
    error (EXIT_FAILURE, errno, _("Reopening shared object `%s' failed"),
           map->l_name);

  /* Now map the section header.  */
  ptr = mmap (NULL, (ehdr->e_shnum * sizeof (ElfW(Shdr))
                     + (ehdr->e_shoff & (pagesize - 1))), PROT_READ,
              MAP_SHARED|MAP_FILE, fd, ehdr->e_shoff & ~(pagesize - 1));
  if (ptr == MAP_FAILED)
    error (EXIT_FAILURE, errno, _("mapping of section headers failed"));
  shdr = (ElfW(Shdr) *) ((char *) ptr + (ehdr->e_shoff & (pagesize - 1)));

  /* Get the section header string table.  */
  ptr = mmap (NULL, (shdr[ehdr->e_shstrndx].sh_size
                     + (shdr[ehdr->e_shstrndx].sh_offset & (pagesize - 1))),
              PROT_READ, MAP_SHARED|MAP_FILE, fd,
              shdr[ehdr->e_shstrndx].sh_offset & ~(pagesize - 1));
  if (ptr == MAP_FAILED)
    error (EXIT_FAILURE, errno,
           _("mapping of section header string table failed"));
  shstrtab = ((const char *) ptr
              + (shdr[ehdr->e_shstrndx].sh_offset & (pagesize - 1)));

  /* Search for the ".symtab" section.  */
  symtab_entry = NULL;
  for (idx = 0; idx < ehdr->e_shnum; ++idx)
    if (shdr[idx].sh_type == SHT_SYMTAB
        && strcmp (shstrtab + shdr[idx].sh_name, ".symtab") == 0)
      {
        symtab_entry = &shdr[idx];
        break;
      }

  /* We don't need the section header string table anymore.  */
  munmap (ptr, (shdr[ehdr->e_shstrndx].sh_size
                + (shdr[ehdr->e_shstrndx].sh_offset & (pagesize - 1))));

  if (symtab_entry == NULL)
    {
      fprintf (stderr, _("\
*** The file `%s' is stripped: no detailed analysis possible\n"),
              name);
      result->symtab = NULL;
      result->strtab = NULL;
    }
  else
    {
      ElfW(Off) min_offset, max_offset;
      ElfW(Shdr) *strtab_entry;

      strtab_entry = &shdr[symtab_entry->sh_link];

      /* Find the minimum and maximum offsets that include both the symbol
         table and the string table.  */
      if (symtab_entry->sh_offset < strtab_entry->sh_offset)
        {
          min_offset = symtab_entry->sh_offset & ~(pagesize - 1);
          max_offset = strtab_entry->sh_offset + strtab_entry->sh_size;
        }
      else
        {
          min_offset = strtab_entry->sh_offset & ~(pagesize - 1);
          max_offset = symtab_entry->sh_offset + symtab_entry->sh_size;
        }

      result->symbol_map = mmap (NULL, max_offset - min_offset,
                                 PROT_READ, MAP_SHARED|MAP_FILE, fd,
                                 min_offset);
      if (result->symbol_map == NULL)
        error (EXIT_FAILURE, errno, _("failed to load symbol data"));

      result->symtab
        = (const ElfW(Sym) *) ((const char *) result->symbol_map
                               + (symtab_entry->sh_offset - min_offset));
      result->symtab_size = symtab_entry->sh_size;
      result->strtab = ((const char *) result->symbol_map
                        + (strtab_entry->sh_offset - min_offset));
      result->symbol_mapsize = max_offset - min_offset;
    }

  /* Now we also don't need the section header table anymore.  */
  munmap ((char *) shdr - (ehdr->e_shoff & (pagesize - 1)),
          (ehdr->e_phnum * sizeof (ElfW(Shdr))
           + (ehdr->e_shoff & (pagesize - 1))));

  /* Free the descriptor for the shared object.  */
  close (fd);

  return result;
}


static void
unload_shobj (struct shobj *shobj)
{
  munmap (shobj->symbol_map, shobj->symbol_mapsize);
  dlclose (shobj->map);
}


static struct profdata *
load_profdata (const char *name, struct shobj *shobj)
{
  struct profdata *result;
  int fd;
  struct stat st;
  void *addr;
  struct gmon_hdr gmon_hdr;
  struct gmon_hist_hdr hist_hdr;
  uint32_t *narcsp;
  size_t fromlimit;
  struct here_cg_arc_record *data;
  struct here_fromstruct *froms;
  uint16_t *tos;
  size_t fromidx;
  size_t idx;

  fd = open (name, O_RDONLY);
  if (fd == -1)
    {
      char *ext_name;

      if (errno != ENOENT || strchr (name, '/') != NULL)
        /* The file exists but we are not allowed to read it or the
           file does not exist and the name includes a path
           specification..  */
        return NULL;

      /* A file with the given name does not exist in the current
         directory, try it in the default location where the profiling
         files are created.  */
      ext_name = (char *) alloca (strlen (name) + sizeof "/var/tmp/");
      stpcpy (stpcpy (ext_name, "/var/tmp/"), name);
      name = ext_name;

      fd = open (ext_name, O_RDONLY);
      if (fd == -1)
        {
          /* Even this file does not exist.  */
          error (0, errno, _("cannot load profiling data"));
          return NULL;
        }
    }

  /* We have found the file, now make sure it is the right one for the
     data file.  */
  if (fstat (fd, &st) < 0)
    {
      error (0, errno, _("while stat'ing profiling data file"));
      close (fd);
      return NULL;
    }

  if (st.st_size != shobj->expected_size)
    {
      error (0, 0,
             _("profiling data file `%s' does not match shared object `%s'"),
             name, shobj->name);
      close (fd);
      return NULL;
    }

  /* The data file is most probably the right one for our shared
     object.  Map it now.  */
  addr = mmap (NULL, st.st_size, PROT_READ, MAP_SHARED|MAP_FILE, fd, 0);
  if (addr == MAP_FAILED)
    {
      error (0, errno, _("failed to mmap the profiling data file"));
      close (fd);
      return NULL;
    }

  /* We don't need the file desriptor anymore.  */
  if (close (fd) < 0)
    {
      error (0, errno, _("error while closing the profiling data file"));
      munmap (addr, st.st_size);
      return NULL;
    }

  /* Prepare the result.  */
  result = (struct profdata *) calloc (1, sizeof (struct profdata));
  if (result == NULL)
    {
      error (0, errno, _("cannot create internal descriptor"));
      munmap (addr, st.st_size);
      return NULL;
    }

  /* Store the address and size so that we can later free the resources.  */
  result->addr = addr;
  result->size = st.st_size;

  /* Pointer to data after the header.  */
  result->hist = (char *) ((struct gmon_hdr *) addr + 1);
  result->hist_hdr = (struct gmon_hist_hdr *) ((char *) result->hist
                                               + sizeof (uint32_t));
  result->kcount = (uint16_t *) ((char *) result->hist + sizeof (uint32_t)
                                 + sizeof (struct gmon_hist_hdr));

  /* Compute pointer to array of the arc information.  */
  narcsp = (uint32_t *) ((char *) result->kcount + shobj->kcountsize
                         + sizeof (uint32_t));
  result->narcs = *narcsp;
  result->data = (struct here_cg_arc_record *) ((char *) narcsp
                                                + sizeof (uint32_t));

  /* Create the gmon_hdr we expect or write.  */
  memset (&gmon_hdr, '\0', sizeof (struct gmon_hdr));
  memcpy (&gmon_hdr.cookie[0], GMON_MAGIC, sizeof (gmon_hdr.cookie));
  *(int32_t *) gmon_hdr.version = GMON_SHOBJ_VERSION;

  /* Create the hist_hdr we expect or write.  */
  *(char **) hist_hdr.low_pc = (char *) shobj->lowpc - shobj->map->l_addr;
  *(char **) hist_hdr.high_pc = (char *) shobj->highpc - shobj->map->l_addr;
  if (do_test)
    printf ("low_pc = %p\nhigh_pc = %p\n",
            *(char **) hist_hdr.low_pc, *(char **) hist_hdr.high_pc);
  *(int32_t *) hist_hdr.hist_size = shobj->kcountsize / sizeof (HISTCOUNTER);
  *(int32_t *) hist_hdr.prof_rate = __profile_frequency ();
  strncpy (hist_hdr.dimen, "seconds", sizeof (hist_hdr.dimen));
  hist_hdr.dimen_abbrev = 's';

  /* Test whether the header of the profiling data is ok.  */
  if (memcmp (addr, &gmon_hdr, sizeof (struct gmon_hdr)) != 0
      || *(uint32_t *) result->hist != GMON_TAG_TIME_HIST
      || memcmp (result->hist_hdr, &hist_hdr,
                 sizeof (struct gmon_hist_hdr)) != 0
      || narcsp[-1] != GMON_TAG_CG_ARC)
    {
      free (result);
      error (0, 0, _("`%s' is no correct profile data file for `%s'"),
             name, shobj->name);
      munmap (addr, st.st_size);
      return NULL;
    }

  /* We are pretty sure now that this is a correct input file.  Set up
     the remaining information in the result structure and return.  */
  result->tos = (uint16_t *) calloc (shobj->tossize + shobj->fromssize, 1);
  if (result->tos == NULL)
    {
      error (0, errno, _("cannot create internal descriptor"));
      munmap (addr, st.st_size);
      free (result);
      return NULL;
    }

  result->froms = (struct here_fromstruct *) ((char *) result->tos
                                              + shobj->tossize);
  fromidx = 0;

  /* Now we have to process all the arc count entries.  */
  fromlimit = shobj->fromlimit;
  data = result->data;
  froms = result->froms;
  tos = result->tos;
  for (idx = 0; idx < MIN (*narcsp, fromlimit); ++idx)
    {
      size_t to_index;
      size_t newfromidx;
      to_index = (data[idx].self_pc / (shobj->hashfraction * sizeof (*tos)));
      newfromidx = fromidx++;
      froms[newfromidx].here = &data[idx];
      froms[newfromidx].link = tos[to_index];
      tos[to_index] = newfromidx;
    }

  return result;
}


static void
unload_profdata (struct profdata *profdata)
{
  free (profdata->tos);
  munmap (profdata->addr, profdata->size);
  free (profdata);
}


static void
count_total_ticks (struct shobj *shobj, struct profdata *profdata)
{
  volatile uint16_t *kcount = profdata->kcount;
  size_t maxkidx = shobj->kcountsize;
  size_t factor = 2 * (65536 / shobj->s_scale);
  size_t kidx = 0;
  size_t sidx = 0;

  while (sidx < symidx)
    {
      uintptr_t start = sortsym[sidx]->addr;
      uintptr_t end = start + sortsym[sidx]->size;

      while (kidx < maxkidx && factor * kidx < start)
        ++kidx;
      if (kidx == maxkidx)
        break;

      while (kidx < maxkidx && factor * kidx < end)
        sortsym[sidx]->ticks += kcount[kidx++];
      if (kidx == maxkidx)
        break;

      total_ticks += sortsym[sidx++]->ticks;
    }
}


static size_t
find_symbol (uintptr_t addr)
{
  size_t sidx = 0;

  while (sidx < symidx)
    {
      uintptr_t start = sortsym[sidx]->addr;
      uintptr_t end = start + sortsym[sidx]->size;

      if (addr >= start && addr < end)
        return sidx;

      if (addr < start)
        break;

      ++sidx;
    }

  return (size_t) -1l;
}


static void
count_calls (struct shobj *shobj, struct profdata *profdata)
{
  struct here_cg_arc_record *data = profdata->data;
  uint32_t narcs = profdata->narcs;
  uint32_t cnt;

  for (cnt = 0; cnt < narcs; ++cnt)
    {
      uintptr_t here = data[cnt].self_pc;
      size_t symbol_idx;

      /* Find the symbol for this address.  */
      symbol_idx = find_symbol (here);
      if (symbol_idx != (size_t) -1l)
        sortsym[symbol_idx]->calls += data[cnt].count;
    }
}


static int
symorder (const void *o1, const void *o2)
{
  const struct known_symbol *p1 = (const struct known_symbol *) o1;
  const struct known_symbol *p2 = (const struct known_symbol *) o2;

  return p1->addr - p2->addr;
}


static void
printsym (const void *node, VISIT value, int level)
{
  if (value == leaf || value == postorder)
    sortsym[symidx++] = *(struct known_symbol **) node;
}


static void
read_symbols (struct shobj *shobj)
{
  void *load_addr = (void *) shobj->map->l_addr;
  int n = 0;

  /* Initialize the obstacks.  */
#define obstack_chunk_alloc malloc
#define obstack_chunk_free free
  obstack_init (&shobj->ob_str);
  obstack_init (&shobj->ob_sym);
  obstack_init (&ob_list);

  /* Process the symbols.  */
  if (shobj->symtab)
    {
      const ElfW(Sym) *sym = shobj->symtab;
      const ElfW(Sym) *sym_end
        = (const ElfW(Sym) *) ((const char *) sym + shobj->symtab_size);
      for (; sym < sym_end; sym++)
        if ((ELFW(ST_TYPE) (sym->st_info) == STT_FUNC
             || ELFW(ST_TYPE) (sym->st_info) == STT_NOTYPE)
            && sym->st_size != 0)
          {
            struct known_symbol **existp;
            struct known_symbol *newsym
              = (struct known_symbol *) obstack_alloc (&shobj->ob_sym,
                                                       sizeof (*newsym));
            if (newsym == NULL)
              error (EXIT_FAILURE, errno, _("cannot allocate symbol data"));

            newsym->name = &shobj->strtab[sym->st_name];
            newsym->addr = sym->st_value;
            newsym->size = sym->st_size;
            newsym->ticks = 0;
            newsym->calls = 0;

            existp = tfind (newsym, &symroot, symorder);
            if (existp == NULL)
              {
                /* New function.  */
                tsearch (newsym, &symroot, symorder);
                ++n;
              }
            else
              {
                /* The function is already defined.  See whether we have
                   a better name here.  */
                if ((*existp)->name[0] == '_' && newsym->name[0] != '_')
                  *existp = newsym;
                else
                  /* We don't need the allocated memory.  */
                  obstack_free (&shobj->ob_sym, newsym);
              }
          }
    }
  else
    {
      /* Blarg, the binary is stripped.  We have to rely on the
         information contained in the dynamic section of the object.  */
      const ElfW(Sym) *symtab = (load_addr
                                 + shobj->map->l_info[DT_SYMTAB]->d_un.d_ptr);
      const char *strtab = (load_addr
                            + shobj->map->l_info[DT_STRTAB]->d_un.d_ptr);

      /* We assume that the string table follows the symbol table,
         because there is no way in ELF to know the size of the
         dynamic symbol table!!  */
      while ((void *) symtab < (void *) strtab)
        {
          if ((ELFW(ST_TYPE)(symtab->st_info) == STT_FUNC
               || ELFW(ST_TYPE)(symtab->st_info) == STT_NOTYPE)
              && symtab->st_size != 0)
            {
              struct known_symbol *newsym;
              struct known_symbol **existp;

              newsym =
                (struct known_symbol *) obstack_alloc (&shobj->ob_sym,
                                                       sizeof (*newsym));
              if (newsym == NULL)
                error (EXIT_FAILURE, errno, _("cannot allocate symbol data"));

              newsym->name = &strtab[symtab->st_name];
              newsym->addr = symtab->st_value;
              newsym->size = symtab->st_size;
              newsym->ticks = 0;
              newsym->froms = NULL;
              newsym->tos = NULL;

              existp = tfind (newsym, &symroot, symorder);
              if (existp == NULL)
                {
                  /* New function.  */
                  tsearch (newsym, &symroot, symorder);
                  ++n;
                }
              else
                {
                  /* The function is already defined.  See whether we have
                     a better name here.  */
                  if ((*existp)->name[0] == '_' && newsym->name[0] != '_')
                    *existp = newsym;
                  else
                    /* We don't need the allocated memory.  */
                    obstack_free (&shobj->ob_sym, newsym);
                }
            }
        }

      ++symtab;
    }

  sortsym = malloc (n * sizeof (struct known_symbol *));
  if (sortsym == NULL)
    abort ();

  twalk (symroot, printsym);
}


static void
add_arcs (struct profdata *profdata)
{
  uint32_t narcs = profdata->narcs;
  struct here_cg_arc_record *data = profdata->data;
  uint32_t cnt;

  for (cnt = 0; cnt < narcs; ++cnt)
    {
      /* First add the incoming arc.  */
      size_t sym_idx = find_symbol (data[cnt].self_pc);

      if (sym_idx != (size_t) -1l)
        {
          struct known_symbol *sym = sortsym[sym_idx];
          struct arc_list *runp = sym->froms;

          while (runp != NULL
                 && ((data[cnt].from_pc == 0 && runp->idx != (size_t) -1l)
                     || (data[cnt].from_pc != 0
                         && (runp->idx == (size_t) -1l
                             || data[cnt].from_pc < sortsym[runp->idx]->addr
                             || (data[cnt].from_pc
                                 >= (sortsym[runp->idx]->addr
                                     + sortsym[runp->idx]->size))))))
            runp = runp->next;

          if (runp == NULL)
            {
              /* We need a new entry.  */
              struct arc_list *newp = (struct arc_list *)
                obstack_alloc (&ob_list, sizeof (struct arc_list));

              if (data[cnt].from_pc == 0)
                newp->idx = (size_t) -1l;
              else
                newp->idx = find_symbol (data[cnt].from_pc);
              newp->count = data[cnt].count;
              newp->next = sym->froms;
              sym->froms = newp;
            }
          else
            /* Increment the counter for the found entry.  */
            runp->count += data[cnt].count;
        }

      /* Now add it to the appropriate outgoing list.  */
      sym_idx = find_symbol (data[cnt].from_pc);
      if (sym_idx != (size_t) -1l)
        {
          struct known_symbol *sym = sortsym[sym_idx];
          struct arc_list *runp = sym->tos;

          while (runp != NULL
                 && (runp->idx == (size_t) -1l
                     || data[cnt].self_pc < sortsym[runp->idx]->addr
                     || data[cnt].self_pc >= (sortsym[runp->idx]->addr
                                              + sortsym[runp->idx]->size)))
            runp = runp->next;

          if (runp == NULL)
            {
              /* We need a new entry.  */
              struct arc_list *newp = (struct arc_list *)
                obstack_alloc (&ob_list, sizeof (struct arc_list));

              newp->idx = find_symbol (data[cnt].self_pc);
              newp->count = data[cnt].count;
              newp->next = sym->tos;
              sym->tos = newp;
            }
          else
            /* Increment the counter for the found entry.  */
            runp->count += data[cnt].count;
        }
    }
}


static int
countorder (const void *p1, const void *p2)
{
  struct known_symbol *s1 = (struct known_symbol *) p1;
  struct known_symbol *s2 = (struct known_symbol *) p2;

  if (s1->ticks != s2->ticks)
    return (int) (s2->ticks - s1->ticks);

  if (s1->calls != s2->calls)
    return (int) (s2->calls - s1->calls);

  return strcmp (s1->name, s2->name);
}


static double tick_unit;
static uintmax_t cumu_ticks;

static void
printflat (const void *node, VISIT value, int level)
{
  if (value == leaf || value == postorder)
    {
      struct known_symbol *s = *(struct known_symbol **) node;

      cumu_ticks += s->ticks;

      printf ("%6.2f%10.2f%9.2f%9" PRIdMAX "%9.2f           %s\n",
              total_ticks ? (100.0 * s->ticks) / total_ticks : 0.0,
              tick_unit * cumu_ticks,
              tick_unit * s->ticks,
              s->calls,
              s->calls ? (s->ticks * 1000000) * tick_unit / s->calls : 0,
              /* FIXME: don't know about called functions.  */
              s->name);
    }
}


/* ARGUSED */
static void
freenoop (void *p)
{
}


static void
generate_flat_profile (struct profdata *profdata)
{
  size_t n;
  void *data = NULL;

  tick_unit = 1.0 / *(uint32_t *) profdata->hist_hdr->prof_rate;

  printf ("Flat profile:\n\n"
          "Each sample counts as %g %s.\n",
          tick_unit, profdata->hist_hdr->dimen);
  fputs ("  %   cumulative   self              self     total\n"
         " time   seconds   seconds    calls  us/call  us/call  name\n",
         stdout);

  for (n = 0; n < symidx; ++n)
    if (sortsym[n]->calls != 0 || sortsym[n]->ticks != 0)
      tsearch (sortsym[n], &data, countorder);

  twalk (data, printflat);

  tdestroy (data, freenoop);
}


static void
generate_call_graph (struct profdata *profdata)
{
  size_t cnt;

  puts ("\nindex % time    self  children    called     name\n");

  for (cnt = 0; cnt < symidx; ++cnt)
    if (sortsym[cnt]->froms != NULL || sortsym[cnt]->tos != NULL)
      {
        struct arc_list *runp;
        size_t n;

        /* First print the from-information.  */
        runp = sortsym[cnt]->froms;
        while (runp != NULL)
          {
            printf ("            %8.2f%8.2f%9" PRIdMAX "/%-9" PRIdMAX "   %s",
                    (runp->idx != (size_t) -1l
                     ? sortsym[runp->idx]->ticks * tick_unit : 0.0),
                    0.0, /* FIXME: what's time for the children, recursive */
                    runp->count, sortsym[cnt]->calls,
                    (runp->idx != (size_t) -1l ?
                     sortsym[runp->idx]->name : "<UNKNOWN>"));

            if (runp->idx != (size_t) -1l)
              printf (" [%Zd]", runp->idx);
            putchar_unlocked ('\n');

            runp = runp->next;
          }

        /* Info abount the function itself.  */
        n = printf ("[%Zu]", cnt);
        printf ("%*s%5.1f%8.2f%8.2f%9" PRIdMAX "         %s [%Zd]\n",
                (int) (7 - n), " ",
                total_ticks ? (100.0 * sortsym[cnt]->ticks) / total_ticks : 0,
                sortsym[cnt]->ticks * tick_unit,
                0.0, /* FIXME: what's time for the children, recursive */
                sortsym[cnt]->calls,
                sortsym[cnt]->name, cnt);

        /* Info about the functions this function calls.  */
        runp = sortsym[cnt]->tos;
        while (runp != NULL)
          {
            printf ("            %8.2f%8.2f%9" PRIdMAX "/",
                    (runp->idx != (size_t) -1l
                     ? sortsym[runp->idx]->ticks * tick_unit : 0.0),
                    0.0, /* FIXME: what's time for the children, recursive */
                    runp->count);

            if (runp->idx != (size_t) -1l)
              printf ("%-9" PRIdMAX "   %s [%Zd]\n",
                      sortsym[runp->idx]->calls,
                      sortsym[runp->idx]->name,
                      runp->idx);
            else
              fputs ("???         <UNKNOWN>\n\n", stdout);

            runp = runp->next;
          }

        fputs ("-----------------------------------------------\n", stdout);
      }
}


static void
generate_call_pair_list (struct profdata *profdata)
{
  size_t cnt;

  for (cnt = 0; cnt < symidx; ++cnt)
    if (sortsym[cnt]->froms != NULL || sortsym[cnt]->tos != NULL)
      {
        struct arc_list *runp;

        /* First print the incoming arcs.  */
        runp = sortsym[cnt]->froms;
        while (runp != NULL)
          {
            if (runp->idx == (size_t) -1l)
              printf ("\
<UNKNOWN>                          %-34s %9" PRIdMAX "\n",
                      sortsym[cnt]->name, runp->count);
            runp = runp->next;
          }

        /* Next the outgoing arcs.  */
        runp = sortsym[cnt]->tos;
        while (runp != NULL)
          {
            printf ("%-34s %-34s %9" PRIdMAX "\n",
                    sortsym[cnt]->name,
                    (runp->idx != (size_t) -1l
                     ? sortsym[runp->idx]->name : "<UNKNOWN>"),
                    runp->count);
            runp = runp->next;
          }
      }
}