gprof/call_graph.c

   1 /* call_graph.c  -  Create call graphs.
   2
   3    Copyright 2000, 2001, 2002 Free Software Foundation, Inc.
   4
   5    This file is part of GNU Binutils.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  20    02111-1307, USA.  */
  21 \f
  22 #include "gprof.h"
  23 #include "search_list.h"
  24 #include "source.h"
  25 #include "symtab.h"
  26 #include "cg_arcs.h"
  27 #include "call_graph.h"
  28 #include "corefile.h"
  29 #include "gmon_io.h"
  30 #include "gmon_out.h"
  31 #include "sym_ids.h"
  32
  33 void
  34 cg_tally (from_pc, self_pc, count)
  35      bfd_vma from_pc;
  36      bfd_vma self_pc;
  37      unsigned long count;
  38 {
  39   Sym *parent;
  40   Sym *child;
  41
  42   parent = sym_lookup (&symtab, from_pc);
  43   child = sym_lookup (&symtab, self_pc);
  44
  45   if (child == NULL || parent == NULL)
  46     return;
  47
  48   /* If we're doing line-by-line profiling, both the parent and the
  49      child will probably point to line symbols instead of function
  50      symbols.  For the parent this is fine, since this identifies the
  51      line number in the calling routing, but the child should always
  52      point to a function entry point, so we back up in the symbol
  53      table until we find it.
  54
  55      For normal profiling, is_func will be set on all symbols, so this
  56      code will do nothing.  */
  57   while (child >= symtab.base && ! child->is_func)
  58     --child;
  59
  60   if (child < symtab.base)
  61     return;
  62
  63   /* Keep arc if it is on INCL_ARCS table or if the INCL_ARCS table
  64      is empty and it is not in the EXCL_ARCS table.  */
  65   if (sym_id_arc_is_present (&syms[INCL_ARCS], parent, child)
  66       || (syms[INCL_ARCS].len == 0
  67           && !sym_id_arc_is_present (&syms[EXCL_ARCS], parent, child)))
  68     {
  69       child->ncalls += count;
  70       DBG (TALLYDEBUG,
  71            printf (_("[cg_tally] arc from %s to %s traversed %lu times\n"),
  72                    parent->name, child->name, count));
  73       arc_add (parent, child, count);
  74     }
  75 }
  76
  77 /* Read a record from file IFP describing an arc in the function
  78    call-graph and the count of how many times the arc has been
  79    traversed.  FILENAME is the name of file IFP and is provided
  80    for formatting error-messages only.  */
  81
  82 void
  83 cg_read_rec (ifp, filename)
  84      FILE *ifp;
  85      const char *filename;
  86 {
  87   bfd_vma from_pc, self_pc;
  88   unsigned int count;
  89
  90   if (gmon_io_read_vma (ifp, &from_pc)
  91       || gmon_io_read_vma (ifp, &self_pc)
  92       || gmon_io_read_32 (ifp, &count))
  93     {
  94       fprintf (stderr, _("%s: %s: unexpected end of file\n"),
  95                whoami, filename);
  96       done (1);
  97     }
  98
  99   DBG (SAMPLEDEBUG,
 100        printf ("[cg_read_rec] frompc 0x%lx selfpc 0x%lx count %lu\n",
 101                (unsigned long) from_pc, (unsigned long) self_pc,
 102                (unsigned long) count));
 103   /* Add this arc:  */
 104   cg_tally (from_pc, self_pc, count);
 105 }
 106
 107 /* Write all the arcs in the call-graph to file OFP.  FILENAME is
 108    the name of OFP and is provided for formatting error-messages
 109    only.  */
 110
 111 void
 112 cg_write_arcs (ofp, filename)
 113      FILE *ofp;
 114      const char *filename;
 115 {
 116   Arc *arc;
 117   Sym *sym;
 118
 119   for (sym = symtab.base; sym < symtab.limit; sym++)
 120     {
 121       for (arc = sym->cg.children; arc; arc = arc->next_child)
 122         {
 123           if (gmon_io_write_8 (ofp, GMON_TAG_CG_ARC)
 124               || gmon_io_write_vma (ofp, arc->parent->addr)
 125               || gmon_io_write_vma (ofp, arc->child->addr)
 126               || gmon_io_write_32 (ofp, arc->count))
 127             {
 128               perror (filename);
 129               done (1);
 130             }
 131           DBG (SAMPLEDEBUG,
 132              printf ("[cg_write_arcs] frompc 0x%lx selfpc 0x%lx count %lu\n",
 133                      (unsigned long) arc->parent->addr,
 134                      (unsigned long) arc->child->addr, arc->count));
 135         }
 136     }
 137 }