toolchain/gcc/libgloss/i386/cygmon-gmon.c

   1 /*-
   2  * Copyright (c) 1991, 2000 The Regents of the University of California.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * This is a modified gmon.c by J.W.Hawtin <oolon@ankh.org>,
  36  * 14/8/96 based on the original gmon.c in GCC and the hacked version
  37  * solaris 2 sparc version (config/sparc/gmon-sol.c) by Mark Eichin. To do
  38  * process profiling on solaris 2.X X86
  39  *
  40  * It must be used in conjunction with sol2-gc1.asm, which is used to start
  41  * and stop process monitoring.
  42  *
  43  * Differences.
  44  *
  45  * On Solaris 2 _mcount is called by library functions not mcount, so support
  46  * has been added for both.
  47  *
  48  * Also the prototype for profil() is different
  49  *
  50  * Solaris 2 does not seem to have char *minbrk which allows the setting of
  51  * the minimum SBRK region so this code has been removed and lets pray malloc
  52  * does not mess it up.
  53  *
  54  * Notes
  55  *
  56  * This code could easily be integrated with the original gmon.c and perhaps
  57  * should be.
  58  */
  59
  60 #ifndef lint
  61 static char sccsid[] = "@(#)gmon.c      5.3 (Berkeley) 5/22/91";
  62 #endif /* not lint */
  63
  64 #define DEBUG
  65 #ifdef DEBUG
  66 #include <stdio.h>
  67 #endif
  68
  69 #include "cygmon-gmon.h"
  70
  71 /*
  72  *      froms is actually a bunch of unsigned shorts indexing tos
  73  */
  74 static int              profiling = 3;
  75 static unsigned short   *froms;
  76 static struct tostruct  *tos = 0;
  77 static long             tolimit = 0;
  78 static char             *s_lowpc = 0;
  79 static char             *s_highpc = 0;
  80 static unsigned long    s_textsize = 0;
  81
  82 static int      ssiz;
  83 static char     *sbuf;
  84 static int      s_scale;
  85     /* see profil(2) where this is describe (incorrectly) */
  86 #define         SCALE_1_TO_1    0x10000L
  87
  88 #define MSG "No space for profiling buffer(s)\n"
  89
  90 extern int errno;
  91
  92 int
  93 monstartup(lowpc, highpc)
  94      char       *lowpc;
  95      char       *highpc;
  96 {
  97   int           monsize;
  98   char          *buffer;
  99   register int  o;
 100
 101         /*
 102          *      round lowpc and highpc to multiples of the density we're using
 103          *      so the rest of the scaling (here and in gprof) stays in ints.
 104          */
 105   lowpc = (char *)
 106     ROUNDDOWN((unsigned)lowpc, HISTFRACTION*sizeof(HISTCOUNTER));
 107   s_lowpc = lowpc;
 108   highpc = (char *)
 109     ROUNDUP((unsigned)highpc, HISTFRACTION*sizeof(HISTCOUNTER));
 110   s_highpc = highpc;
 111   s_textsize = highpc - lowpc;
 112   monsize = (s_textsize / HISTFRACTION) + sizeof(struct phdr);
 113   buffer = (char *) sbrk (monsize);
 114   if (buffer == (char *) -1)
 115     {
 116       write (2, MSG , sizeof(MSG));
 117       return;
 118     }
 119   bzero (buffer, monsize);
 120   froms = (unsigned short *) sbrk (s_textsize / HASHFRACTION);
 121   if (froms == (unsigned short *) -1)
 122     {
 123       write(2, MSG, sizeof(MSG));
 124       froms = 0;
 125       return;
 126     }
 127   bzero (froms, s_textsize / HASHFRACTION);
 128   tolimit = s_textsize * ARCDENSITY / 100;
 129   if (tolimit < MINARCS)
 130     {
 131       tolimit = MINARCS;
 132     }
 133   else
 134     {
 135       if (tolimit > 65534)
 136         {
 137           tolimit = 65534;
 138         }
 139     }
 140   tos = (struct tostruct *) sbrk( tolimit * sizeof( struct tostruct ) );
 141   if (tos == (struct tostruct *) -1)
 142     {
 143       write (2, MSG, sizeof(MSG));
 144       froms = 0;
 145       tos = 0;
 146       return;
 147     }
 148   bzero (tos, tolimit * sizeof( struct tostruct ) );
 149   tos[0].link = 0;
 150   sbuf = buffer;
 151   ssiz = monsize;
 152   ( (struct phdr *) buffer ) -> lpc = lowpc;
 153   ( (struct phdr *) buffer ) -> hpc = highpc;
 154   ( (struct phdr *) buffer ) -> ncnt = ssiz;
 155   monsize -= sizeof(struct phdr);
 156   if ( monsize <= 0 )
 157     return;
 158   o = highpc - lowpc;
 159   if (monsize < o)
 160     {
 161         s_scale = ( (float) monsize / o ) * SCALE_1_TO_1;
 162     }
 163   else
 164     s_scale = SCALE_1_TO_1;
 165   moncontrol (1);
 166 }
 167
 168 void
 169 _mcleanup()
 170 {
 171   int           fd;
 172   int           fromindex;
 173   int           endfrom;
 174   char          *frompc;
 175   int           toindex;
 176   struct rawarc rawarc;
 177
 178   moncontrol (0);
 179   profil_write (1, sbuf, ssiz);
 180
 181   endfrom = s_textsize / (HASHFRACTION * sizeof(*froms));
 182   for ( fromindex = 0 ; fromindex < endfrom ; fromindex++ )
 183     {
 184       if ( froms[fromindex] == 0 )
 185         {
 186           continue;
 187         }
 188       frompc = s_lowpc + (fromindex * HASHFRACTION * sizeof(*froms));
 189       for (toindex=froms[fromindex]; toindex!=0; toindex=tos[toindex].link)
 190         {
 191           rawarc.raw_frompc = (unsigned long) frompc;
 192           rawarc.raw_selfpc = (unsigned long) tos[toindex].selfpc;
 193           rawarc.raw_count = tos[toindex].count;
 194           profil_write (2, &rawarc, sizeof (rawarc));
 195         }
 196     }
 197   profil_write (3, 0, 0);
 198 }
 199
 200 static char already_setup = 0;
 201
 202 _mcount()
 203 {
 204   register char                 *selfpc;
 205   register unsigned short       *frompcindex;
 206   register struct tostruct      *top;
 207   register struct tostruct      *prevtop;
 208   register long                 toindex;
 209
 210   /*
 211    *    find the return address for mcount,
 212    *    and the return address for mcount's caller.
 213    */
 214
 215   /* selfpc = pc pushed by mcount call.
 216      This identifies the function that was just entered.  */
 217   selfpc = (void *) __builtin_return_address (0);
 218   /* frompcindex = pc in preceding frame.
 219      This identifies the caller of the function just entered.  */
 220   frompcindex = (void *) __builtin_return_address (1);
 221
 222   if (! already_setup)
 223     {
 224       extern _etext();
 225       extern _ftext();
 226       already_setup = 1;
 227       monstartup(_ftext, _etext);
 228       atexit(_mcleanup);
 229     }
 230   /*
 231    *    check that we are profiling
 232    *    and that we aren't recursively invoked.
 233    */
 234   if (profiling)
 235     {
 236       goto out;
 237     }
 238   profiling++;
 239   /*
 240    *    check that frompcindex is a reasonable pc value.
 241    *    for example:    signal catchers get called from the stack,
 242    *                    not from text space.  too bad.
 243    */
 244   frompcindex = (unsigned short *)((long)frompcindex - (long)s_lowpc);
 245   if ((unsigned long)frompcindex > s_textsize)
 246     {
 247       goto done;
 248     }
 249   frompcindex =
 250     &froms[((long)frompcindex) / (HASHFRACTION * sizeof(*froms))];
 251   toindex = *frompcindex;
 252   if (toindex == 0)
 253     {
 254       /*
 255        *        first time traversing this arc
 256        */
 257       toindex = ++tos[0].link;
 258       if (toindex >= tolimit)
 259         {
 260           goto overflow;
 261         }
 262       *frompcindex = toindex;
 263       top = &tos[toindex];
 264       top->selfpc = selfpc;
 265       top->count = 1;
 266       top->link = 0;
 267       goto done;
 268     }
 269   top = &tos[toindex];
 270   if (top->selfpc == selfpc)
 271     {
 272       /*
 273        *        arc at front of chain; usual case.
 274        */
 275       top->count++;
 276       goto done;
 277     }
 278   /*
 279    *    have to go looking down chain for it.
 280    *    top points to what we are looking at,
 281    *    prevtop points to previous top.
 282    *    we know it is not at the head of the chain.
 283    */
 284   for (; /* goto done */; )
 285     {
 286       if (top->link == 0)
 287         {
 288           /*
 289            *    top is end of the chain and none of the chain
 290            *    had top->selfpc == selfpc.
 291            *    so we allocate a new tostruct
 292            *    and link it to the head of the chain.
 293            */
 294           toindex = ++tos[0].link;
 295           if (toindex >= tolimit)
 296             {
 297               goto overflow;
 298             }
 299           top = &tos[toindex];
 300           top->selfpc = selfpc;
 301           top->count = 1;
 302           top->link = *frompcindex;
 303           *frompcindex = toindex;
 304           goto done;
 305         }
 306       /*
 307        *        otherwise, check the next arc on the chain.
 308        */
 309       prevtop = top;
 310       top = &tos[top->link];
 311       if (top->selfpc == selfpc)
 312         {
 313           /*
 314            *    there it is.
 315            *    increment its count
 316            *    move it to the head of the chain.
 317            */
 318           top->count++;
 319           toindex = prevtop->link;
 320           prevtop->link = top->link;
 321           top->link = *frompcindex;
 322           *frompcindex = toindex;
 323           goto done;
 324         }
 325     }
 326 done:
 327   profiling--;
 328   /* and fall through */
 329 out:
 330   return;               /* normal return restores saved registers */
 331
 332 overflow:
 333   profiling++; /* halt further profiling */
 334 #   define      TOLIMIT "mcount: tos overflow\n"
 335   write (2, TOLIMIT, sizeof(TOLIMIT));
 336   goto out;
 337 }
 338
 339 /*
 340  * Control profiling
 341  *      profiling is what mcount checks to see if
 342  *      all the data structures are ready.
 343  */
 344 moncontrol(mode)
 345     int mode;
 346 {
 347   if (mode)
 348     {
 349       /* start */
 350       profil((unsigned short *)(sbuf + sizeof(struct phdr)),
 351              ssiz - sizeof(struct phdr),
 352              (int)s_lowpc, s_scale);
 353
 354       profiling = 0;
 355     }
 356   else
 357     {
 358       /* stop */
 359       profil((unsigned short *)0, 0, 0, 0);
 360       profiling = 3;
 361     }
 362 }