gprof/symtab.c

   1 #include "gprof.h"
   2 #include "cg_arcs.h"
   3 #include "core.h"
   4 #include "symtab.h"
   5
   6 Sym_Table symtab;
   7
   8
   9 /*
  10  * Initialize a symbol (so it's empty).
  11  */
  12 void
  13 DEFUN (sym_init, (sym), Sym * sym)
  14 {
  15   memset (sym, 0, sizeof (*sym));
  16   /*
  17    * It is not safe to assume that a binary zero corresponds to
  18    * a floating-point 0.0, so initialize floats explicitly:
  19    */
  20   sym->hist.time = 0.0;
  21   sym->cg.child_time = 0.0;
  22   sym->cg.prop.fract = 0.0;
  23   sym->cg.prop.self = 0.0;
  24   sym->cg.prop.child = 0.0;
  25 }
  26
  27
  28 /*
  29  * Compare the function entry-point of two symbols and return <0, =0,
  30  * or >0 depending on whether the left value is smaller than, equal
  31  * to, or greater than the right value.  If two symbols are equal
  32  * but one has is_func set and the other doesn't, we make the
  33  * non-function symbol one "bigger" so that the function symbol will
  34  * survive duplicate removal.  Finally, if both symbols have the
  35  * same is_func value, we discriminate against is_static such that
  36  * the global symbol survives.
  37  */
  38 static int
  39 DEFUN (cmp_addr, (lp, rp), const PTR lp AND const PTR rp)
  40 {
  41   Sym *left = (Sym *) lp;
  42   Sym *right = (Sym *) rp;
  43
  44   if (left->addr > right->addr)
  45     {
  46       return 1;
  47     }
  48   else if (left->addr < right->addr)
  49     {
  50       return -1;
  51     }
  52
  53   if (left->is_func != right->is_func)
  54     {
  55       return right->is_func - left->is_func;
  56     }
  57
  58   return left->is_static - right->is_static;
  59 }
  60
  61
  62 void
  63 DEFUN (symtab_finalize, (tab), Sym_Table * tab)
  64 {
  65   Sym *src, *dst;
  66   bfd_vma prev_addr;
  67
  68   if (!tab->len)
  69     {
  70       return;
  71     }
  72
  73   /*
  74    * Sort symbol table in order of increasing function addresses:
  75    */
  76   qsort (tab->base, tab->len, sizeof (Sym), cmp_addr);
  77
  78   /*
  79    * Remove duplicate entries to speed-up later processing and
  80    * set end_addr if its not set yet:
  81    */
  82   prev_addr = tab->base[0].addr + 1;
  83   for (src = dst = tab->base; src < tab->limit; ++src)
  84     {
  85       if (src->addr == prev_addr)
  86         {
  87           /*
  88            * If same address, favor global symbol over static one.
  89            * If both symbols are either static or global, check
  90            * whether one has name beginning with underscore while
  91            * the other doesn't.  In such cases, keep sym without
  92            * underscore.  This takes cares of compiler generated
  93            * symbols (such as __gnu_compiled, __c89_used, etc.).
  94            */
  95           if ((!src->is_static && dst[-1].is_static)
  96               || ((src->is_static == dst[-1].is_static) &&
  97                   (src->name[0] != '_' && dst[-1].name[0] == '_')
  98                   || (src->name[0]
  99                       && src->name[1] != '_' && dst[-1].name[1] == '_')))
 100             {
 101               DBG (AOUTDEBUG | IDDEBUG,
 102                    printf ("[symtab_finalize] favor %s@%c%c over %s@%c%c",
 103                            src->name, src->is_static ? 't' : 'T',
 104                            src->is_func ? 'F' : 'f',
 105                            dst[-1].name, dst[-1].is_static ? 't' : 'T',
 106                            dst[-1].is_func ? 'F' : 'f');
 107                    printf (" (addr=%lx)\n", src->addr));
 108               dst[-1] = *src;
 109             }
 110           else
 111             {
 112               DBG (AOUTDEBUG | IDDEBUG,
 113                    printf ("[symtab_finalize] favor %s@%c%c over %s@%c%c",
 114                            dst[-1].name, dst[-1].is_static ? 't' : 'T',
 115                            dst[-1].is_func ? 'F' : 'f',
 116                            src->name, src->is_static ? 't' : 'T',
 117                            src->is_func ? 'F' : 'f');
 118                    printf (" (addr=%lx)\n", src->addr));
 119             }
 120         }
 121       else
 122         {
 123           if (dst > tab->base && dst[-1].end_addr == 0)
 124             {
 125               dst[-1].end_addr = src->addr - 1;
 126             }
 127
 128           /* retain sym only if it has a non-empty address range: */
 129           if (!src->end_addr || src->addr <= src->end_addr)
 130             {
 131               *dst++ = *src;
 132               prev_addr = src->addr;
 133             }
 134         }
 135     }
 136   if (tab->len > 0 && dst[-1].end_addr == 0)
 137     {
 138       dst[-1].end_addr = core_text_sect->vma + core_text_sect->_raw_size - 1;
 139     }
 140
 141   DBG (AOUTDEBUG | IDDEBUG,
 142        printf ("[symtab_finalize]: removed %d duplicate entries\n",
 143                tab->len - (int) (dst - tab->base)));
 144
 145   tab->limit = dst;
 146   tab->len = tab->limit - tab->base;
 147
 148   DBG (AOUTDEBUG | IDDEBUG,
 149        int j;
 150
 151        for (j = 0; j < tab->len; ++j)
 152        {
 153        printf ("[symtab_finalize] 0x%lx-0x%lx\t%s\n",
 154                (long) tab->base[j].addr, (long) tab->base[j].end_addr,
 155                tab->base[j].name);
 156        }
 157   );
 158 }
 159
 160
 161 #ifdef DEBUG
 162
 163 Sym *
 164 DEFUN (dbg_sym_lookup, (symtab, address), Sym_Table * symtab AND bfd_vma address)
 165 {
 166   long low, mid, high;
 167   Sym *sym;
 168
 169   fprintf (stderr, "[sym_lookup] address 0x%lx\n", address);
 170
 171   sym = symtab->base;
 172   for (low = 0, high = symtab->len - 1; low != high;)
 173     {
 174       mid = (high + low) >> 1;
 175       fprintf (stderr, "[dbg_sym_lookup] low=0x%lx, mid=0x%lx, high=0x%lx\n",
 176                low, mid, high);
 177       fprintf (stderr, "[dbg_sym_lookup] sym[m]=0x%lx sym[m + 1]=0x%lx\n",
 178                sym[mid].addr, sym[mid + 1].addr);
 179       if (sym[mid].addr <= address && sym[mid + 1].addr > address)
 180         {
 181           return &sym[mid];
 182         }
 183       if (sym[mid].addr > address)
 184         {
 185           high = mid;
 186         }
 187       else
 188         {
 189           low = mid + 1;
 190         }
 191     }
 192   fprintf (stderr, "[sym_lookup] binary search fails???\n");
 193   return 0;
 194 }
 195
 196 #endif  /* DEBUG */
 197
 198
 199 /*
 200  * Look up an address in the symbol-table that is sorted by address.
 201  * If address does not hit any symbol, 0 is returned.
 202  */
 203 Sym *
 204 DEFUN (sym_lookup, (symtab, address), Sym_Table * symtab AND bfd_vma address)
 205 {
 206   long low, high;
 207   long mid = -1;
 208   Sym *sym;
 209 #ifdef DEBUG
 210   int probes = 0;
 211 #endif /* DEBUG */
 212
 213   if (!symtab->len)
 214     {
 215       return 0;
 216     }
 217
 218   sym = symtab->base;
 219   for (low = 0, high = symtab->len - 1; low != high;)
 220     {
 221       DBG (LOOKUPDEBUG, ++probes);
 222       mid = (high + low) / 2;
 223       if (sym[mid].addr <= address && sym[mid + 1].addr > address)
 224         {
 225           if (address > sym[mid].end_addr)
 226             {
 227               /*
 228                * Address falls into gap between sym[mid] and
 229                * sym[mid + 1]:
 230                */
 231               return 0;
 232             }
 233           else
 234             {
 235               DBG (LOOKUPDEBUG,
 236                    printf ("[sym_lookup] %d probes (symtab->len=%d)\n",
 237                            probes, symtab->len - 1));
 238               return &sym[mid];
 239             }
 240         }
 241       if (sym[mid].addr > address)
 242         {
 243           high = mid;
 244         }
 245       else
 246         {
 247           low = mid + 1;
 248         }
 249     }
 250   if (sym[mid + 1].addr <= address)
 251     {
 252       if (address > sym[mid + 1].end_addr)
 253         {
 254           /* address is beyond end of sym[mid + 1]: */
 255           return 0;
 256         }
 257       else
 258         {
 259           DBG (LOOKUPDEBUG, printf ("[sym_lookup] %d (%d) probes, fall off\n",
 260                                     probes, symtab->len - 1));
 261           return &sym[mid + 1];
 262         }
 263     }
 264   return 0;
 265 }