Subversion Repositories openrisc_2011-10-31

/*

 * Copyright (c) 1983, 1993, 2001

 *      The Regents of the University of California.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the University nor the names of its contributors

 *    may be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#include "gprof.h"

#include "libiberty.h"

#include "search_list.h"

#include "source.h"

#include "symtab.h"

#include "call_graph.h"

#include "cg_arcs.h"

#include "cg_dfn.h"

#include "cg_print.h"

#include "utils.h"

#include "sym_ids.h"

static int cmp_topo (const PTR, const PTR);

static void propagate_time (Sym *);

static void cycle_time (void);

static void cycle_link (void);

static void inherit_flags (Sym *);

static void propagate_flags (Sym **);

static int cmp_total (const PTR, const PTR);

Sym *cycle_header;

unsigned int num_cycles;

Arc **arcs;

unsigned int numarcs;

/*

 * Return TRUE iff PARENT has an arc to covers the address

 * range covered by CHILD.

 */

Arc *

arc_lookup (Sym *parent, Sym *child)

{

  Arc *arc;

  if (!parent || !child)

    {

      printf ("[arc_lookup] parent == 0 || child == 0\n");

      return 0;

    }

  DBG (LOOKUPDEBUG, printf ("[arc_lookup] parent %s child %s\n",

                            parent->name, child->name));

  for (arc = parent->cg.children; arc; arc = arc->next_child)

    {

      DBG (LOOKUPDEBUG, printf ("[arc_lookup]\t parent %s child %s\n",

                                arc->parent->name, arc->child->name));

      if (child->addr >= arc->child->addr

          && child->end_addr <= arc->child->end_addr)

        {

          return arc;

        }

    }

  return 0;

}

/*

 * Add (or just increment) an arc:

 */

void

arc_add (Sym *parent, Sym *child, unsigned long count)

{

  static unsigned int maxarcs = 0;

  Arc *arc, **newarcs;

  DBG (TALLYDEBUG, printf ("[arc_add] %lu arcs from %s to %s\n",

                           count, parent->name, child->name));

  arc = arc_lookup (parent, child);

  if (arc)

    {

      /*

       * A hit: just increment the count.

       */

      DBG (TALLYDEBUG, printf ("[tally] hit %lu += %lu\n",

                               arc->count, count));

      arc->count += count;

      return;

    }

  arc = (Arc *) xmalloc (sizeof (*arc));

  memset (arc, 0, sizeof (*arc));

  arc->parent = parent;

  arc->child = child;

  arc->count = count;

  /* If this isn't an arc for a recursive call to parent, then add it

     to the array of arcs.  */

  if (parent != child)

    {

      /* If we've exhausted space in our current array, get a new one

         and copy the contents.   We might want to throttle the doubling

         factor one day.  */

      if (numarcs == maxarcs)

        {

          /* Determine how much space we want to allocate.  */

          if (maxarcs == 0)

            maxarcs = 1;

          maxarcs *= 2;

          /* Allocate the new array.  */

          newarcs = (Arc **)xmalloc(sizeof (Arc *) * maxarcs);

          /* Copy the old array's contents into the new array.  */

          memcpy (newarcs, arcs, numarcs * sizeof (Arc *));

          /* Free up the old array.  */

          free (arcs);

          /* And make the new array be the current array.  */

          arcs = newarcs;

        }

      /* Place this arc in the arc array.  */

      arcs[numarcs++] = arc;

    }

  /* prepend this child to the children of this parent: */

  arc->next_child = parent->cg.children;

  parent->cg.children = arc;

  /* prepend this parent to the parents of this child: */

  arc->next_parent = child->cg.parents;

  child->cg.parents = arc;

}

static int

cmp_topo (const PTR lp, const PTR rp)

{

  const Sym *left = *(const Sym **) lp;

  const Sym *right = *(const Sym **) rp;

  return left->cg.top_order - right->cg.top_order;

}

static void

propagate_time (Sym *parent)

{

  Arc *arc;

  Sym *child;

  double share, prop_share;

  if (parent->cg.prop.fract == 0.0)

    {

      return;

    }

  /* gather time from children of this parent: */

  for (arc = parent->cg.children; arc; arc = arc->next_child)

    {

      child = arc->child;

      if (arc->count == 0 || child == parent || child->cg.prop.fract == 0)

        {

          continue;

        }

      if (child->cg.cyc.head != child)

        {

          if (parent->cg.cyc.num == child->cg.cyc.num)

            {

              continue;

            }

          if (parent->cg.top_order <= child->cg.top_order)

            {

              fprintf (stderr, "[propagate] toporder botches\n");

            }

          child = child->cg.cyc.head;

        }

      else

        {

          if (parent->cg.top_order <= child->cg.top_order)

            {

              fprintf (stderr, "[propagate] toporder botches\n");

              continue;

            }

        }

      if (child->ncalls == 0)

        {

          continue;

        }

      /* distribute time for this arc: */

      arc->time = child->hist.time * (((double) arc->count)

                                      / ((double) child->ncalls));

      arc->child_time = child->cg.child_time

        * (((double) arc->count) / ((double) child->ncalls));

      share = arc->time + arc->child_time;

      parent->cg.child_time += share;

      /* (1 - cg.prop.fract) gets lost along the way: */

      prop_share = parent->cg.prop.fract * share;

      /* fix things for printing: */

      parent->cg.prop.child += prop_share;

      arc->time *= parent->cg.prop.fract;

      arc->child_time *= parent->cg.prop.fract;

      /* add this share to the parent's cycle header, if any: */

      if (parent->cg.cyc.head != parent)

        {

          parent->cg.cyc.head->cg.child_time += share;

          parent->cg.cyc.head->cg.prop.child += prop_share;

        }

      DBG (PROPDEBUG,

           printf ("[prop_time] child \t");

           print_name (child);

           printf (" with %f %f %lu/%lu\n", child->hist.time,

                   child->cg.child_time, arc->count, child->ncalls);

           printf ("[prop_time] parent\t");

           print_name (parent);

           printf ("\n[prop_time] share %f\n", share));

    }

}

/*

 * Compute the time of a cycle as the sum of the times of all

 * its members.

 */

static void

cycle_time ()

{

  Sym *member, *cyc;

  for (cyc = &cycle_header[1]; cyc <= &cycle_header[num_cycles]; ++cyc)

    {

      for (member = cyc->cg.cyc.next; member; member = member->cg.cyc.next)

        {

          if (member->cg.prop.fract == 0.0)

            {

              /*

               * All members have the same propfraction except those

               * that were excluded with -E.

               */

              continue;

            }

          cyc->hist.time += member->hist.time;

        }

      cyc->cg.prop.self = cyc->cg.prop.fract * cyc->hist.time;

    }

}

static void

cycle_link ()

{

  Sym *sym, *cyc, *member;

  Arc *arc;

  int num;

  /* count the number of cycles, and initialize the cycle lists: */

  num_cycles = 0;

  for (sym = symtab.base; sym < symtab.limit; ++sym)

    {

      /* this is how you find unattached cycles: */

      if (sym->cg.cyc.head == sym && sym->cg.cyc.next)

        {

          ++num_cycles;

        }

    }

  /*

   * cycle_header is indexed by cycle number: i.e. it is origin 1,

   * not origin 0.

   */

  cycle_header = (Sym *) xmalloc ((num_cycles + 1) * sizeof (Sym));

  /*

   * Now link cycles to true cycle-heads, number them, accumulate

   * the data for the cycle.

   */

  num = 0;

  cyc = cycle_header;

  for (sym = symtab.base; sym < symtab.limit; ++sym)

    {

      if (!(sym->cg.cyc.head == sym && sym->cg.cyc.next != 0))

        {

          continue;

        }

      ++num;

      ++cyc;

      sym_init (cyc);

      cyc->cg.print_flag = TRUE;        /* should this be printed? */

      cyc->cg.top_order = DFN_NAN;      /* graph call chain top-sort order */

      cyc->cg.cyc.num = num;    /* internal number of cycle on */

      cyc->cg.cyc.head = cyc;   /* pointer to head of cycle */

      cyc->cg.cyc.next = sym;   /* pointer to next member of cycle */

      DBG (CYCLEDEBUG, printf ("[cycle_link] ");

           print_name (sym);

           printf (" is the head of cycle %d\n", num));

      /* link members to cycle header: */

      for (member = sym; member; member = member->cg.cyc.next)

        {

          member->cg.cyc.num = num;

          member->cg.cyc.head = cyc;

        }

      /*

       * Count calls from outside the cycle and those among cycle

       * members:

       */

      for (member = sym; member; member = member->cg.cyc.next)

        {

          for (arc = member->cg.parents; arc; arc = arc->next_parent)

            {

              if (arc->parent == member)

                {

                  continue;

                }

              if (arc->parent->cg.cyc.num == num)

                {

                  cyc->cg.self_calls += arc->count;

                }

              else

                {

                  cyc->ncalls += arc->count;

                }

            }

        }

    }

}

/*

 * Check if any parent of this child (or outside parents of this

 * cycle) have their print flags on and set the print flag of the

 * child (cycle) appropriately.  Similarly, deal with propagation

 * fractions from parents.

 */

static void

inherit_flags (Sym *child)

{

  Sym *head, *parent, *member;

  Arc *arc;

  head = child->cg.cyc.head;

  if (child == head)

    {

      /* just a regular child, check its parents: */

      child->cg.print_flag = FALSE;

      child->cg.prop.fract = 0.0;

      for (arc = child->cg.parents; arc; arc = arc->next_parent)

        {

          parent = arc->parent;

          if (child == parent)

            {

              continue;

            }

          child->cg.print_flag |= parent->cg.print_flag;

          /*

           * If the child was never actually called (e.g., this arc

           * is static (and all others are, too)) no time propagates

           * along this arc.

           */

          if (child->ncalls != 0)

            {

              child->cg.prop.fract += parent->cg.prop.fract

                * (((double) arc->count) / ((double) child->ncalls));

            }

        }

    }

  else

    {

      /*

       * Its a member of a cycle, look at all parents from outside

       * the cycle.

       */

      head->cg.print_flag = FALSE;

      head->cg.prop.fract = 0.0;

      for (member = head->cg.cyc.next; member; member = member->cg.cyc.next)

        {

          for (arc = member->cg.parents; arc; arc = arc->next_parent)

            {

              if (arc->parent->cg.cyc.head == head)

                {

                  continue;

                }

              parent = arc->parent;

              head->cg.print_flag |= parent->cg.print_flag;

              /*

               * If the cycle was never actually called (e.g. this

               * arc is static (and all others are, too)) no time

               * propagates along this arc.

               */

              if (head->ncalls != 0)

                {

                  head->cg.prop.fract += parent->cg.prop.fract

                    * (((double) arc->count) / ((double) head->ncalls));

                }

            }

        }

      for (member = head; member; member = member->cg.cyc.next)

        {

          member->cg.print_flag = head->cg.print_flag;

          member->cg.prop.fract = head->cg.prop.fract;

        }

    }

}

/*

 * In one top-to-bottom pass over the topologically sorted symbols

 * propagate:

 *      cg.print_flag as the union of parents' print_flags

 *      propfraction as the sum of fractional parents' propfractions

 * and while we're here, sum time for functions.

 */

static void

propagate_flags (Sym **symbols)

{

  int index;

  Sym *old_head, *child;

  old_head = 0;

  for (index = symtab.len - 1; index >= 0; --index)

    {

      child = symbols[index];

      /*

       * If we haven't done this function or cycle, inherit things

       * from parent.  This way, we are linear in the number of arcs

       * since we do all members of a cycle (and the cycle itself)

       * as we hit the first member of the cycle.

       */

      if (child->cg.cyc.head != old_head)

        {

          old_head = child->cg.cyc.head;

          inherit_flags (child);

        }

      DBG (PROPDEBUG,

           printf ("[prop_flags] ");

           print_name (child);

           printf ("inherits print-flag %d and prop-fract %f\n",

                   child->cg.print_flag, child->cg.prop.fract));

      if (!child->cg.print_flag)

        {

          /*

           * Printflag is off. It gets turned on by being in the

           * INCL_GRAPH table, or there being an empty INCL_GRAPH

           * table and not being in the EXCL_GRAPH table.

           */

          if (sym_lookup (&syms[INCL_GRAPH], child->addr)

              || (syms[INCL_GRAPH].len == 0

                  && !sym_lookup (&syms[EXCL_GRAPH], child->addr)))

            {

              child->cg.print_flag = TRUE;

            }

        }

      else

        {

          /*

           * This function has printing parents: maybe someone wants

           * to shut it up by putting it in the EXCL_GRAPH table.

           * (But favor INCL_GRAPH over EXCL_GRAPH.)

           */

          if (!sym_lookup (&syms[INCL_GRAPH], child->addr)

              && sym_lookup (&syms[EXCL_GRAPH], child->addr))

            {

              child->cg.print_flag = FALSE;

            }

        }

      if (child->cg.prop.fract == 0.0)

        {

          /*

           * No parents to pass time to.  Collect time from children

           * if its in the INCL_TIME table, or there is an empty

           * INCL_TIME table and its not in the EXCL_TIME table.

           */

          if (sym_lookup (&syms[INCL_TIME], child->addr)

              || (syms[INCL_TIME].len == 0

                  && !sym_lookup (&syms[EXCL_TIME], child->addr)))

            {

              child->cg.prop.fract = 1.0;

            }

        }

      else

        {

          /*

           * It has parents to pass time to, but maybe someone wants

           * to shut it up by puttting it in the EXCL_TIME table.

           * (But favor being in INCL_TIME tabe over being in

           * EXCL_TIME table.)

           */

          if (!sym_lookup (&syms[INCL_TIME], child->addr)

              && sym_lookup (&syms[EXCL_TIME], child->addr))

            {

              child->cg.prop.fract = 0.0;

            }

        }

      child->cg.prop.self = child->hist.time * child->cg.prop.fract;

      print_time += child->cg.prop.self;

      DBG (PROPDEBUG,

           printf ("[prop_flags] ");

           print_name (child);

           printf (" ends up with printflag %d and prop-fract %f\n",

                   child->cg.print_flag, child->cg.prop.fract);

           printf ("[prop_flags] time %f propself %f print_time %f\n",

                   child->hist.time, child->cg.prop.self, print_time));

    }

}

/*

 * Compare by decreasing propagated time.  If times are equal, but one

 * is a cycle header, say that's first (e.g. less, i.e. -1).  If one's

 * name doesn't have an underscore and the other does, say that one is

 * first.  All else being equal, compare by names.

 */

static int

cmp_total (const PTR lp, const PTR rp)

{

  const Sym *left = *(const Sym **) lp;

  const Sym *right = *(const Sym **) rp;

  double diff;

  diff = (left->cg.prop.self + left->cg.prop.child)

    - (right->cg.prop.self + right->cg.prop.child);

  if (diff < 0.0)

    {

      return 1;

    }

  if (diff > 0.0)

    {

      return -1;

    }

  if (!left->name && left->cg.cyc.num != 0)

    {

      return -1;

    }

  if (!right->name && right->cg.cyc.num != 0)

    {

      return 1;

    }

  if (!left->name)

    {

      return -1;

    }

  if (!right->name)

    {

      return 1;

    }

  if (left->name[0] != '_' && right->name[0] == '_')

    {

      return -1;

    }

  if (left->name[0] == '_' && right->name[0] != '_')

    {

      return 1;

    }

  if (left->ncalls > right->ncalls)

    {

      return -1;

    }

  if (left->ncalls < right->ncalls)

    {

      return 1;

    }

  return strcmp (left->name, right->name);

}

/*

 * Topologically sort the graph (collapsing cycles), and propagates

 * time bottom up and flags top down.

 */

Sym **

cg_assemble ()

{

  Sym *parent, **time_sorted_syms, **top_sorted_syms;

  unsigned int index;

  Arc *arc;

  /*

   * initialize various things:

   *      zero out child times.

   *      count self-recursive calls.

   *      indicate that nothing is on cycles.

   */

  for (parent = symtab.base; parent < symtab.limit; parent++)

    {

      parent->cg.child_time = 0.0;

      arc = arc_lookup (parent, parent);

      if (arc && parent == arc->child)

        {

          parent->ncalls -= arc->count;

          parent->cg.self_calls = arc->count;

        }

      else

        {

          parent->cg.self_calls = 0;

        }

      parent->cg.prop.fract = 0.0;

      parent->cg.prop.self = 0.0;

      parent->cg.prop.child = 0.0;

      parent->cg.print_flag = FALSE;

      parent->cg.top_order = DFN_NAN;

      parent->cg.cyc.num = 0;

      parent->cg.cyc.head = parent;

      parent->cg.cyc.next = 0;

      if (ignore_direct_calls)

        {

          find_call (parent, parent->addr, (parent + 1)->addr);

        }

    }

  /*

   * Topologically order things.  If any node is unnumbered, number

   * it and any of its descendents.

   */

  for (parent = symtab.base; parent < symtab.limit; parent++)

    {

      if (parent->cg.top_order == DFN_NAN)

        {

          cg_dfn (parent);

        }

    }

  /* link together nodes on the same cycle: */

  cycle_link ();

  /* sort the symbol table in reverse topological order: */

  top_sorted_syms = (Sym **) xmalloc (symtab.len * sizeof (Sym *));

  for (index = 0; index < symtab.len; ++index)

    {

      top_sorted_syms[index] = &symtab.base[index];

    }

  qsort (top_sorted_syms, symtab.len, sizeof (Sym *), cmp_topo);

  DBG (DFNDEBUG,

       printf ("[cg_assemble] topological sort listing\n");

       for (index = 0; index < symtab.len; ++index)

       {

       printf ("[cg_assemble] ");

       printf ("%d:", top_sorted_syms[index]->cg.top_order);

       print_name (top_sorted_syms[index]);

       printf ("\n");

       }

  );