Reset branch to trunk.

[official-gcc.git] / trunk / gcc / config / sparc / gmon-sol2.c

/*-
 * Copyright (c) 1991 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. [rescinded 22 July 1999]
 * 4. 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.
 */

/* Mangled into a form that works on SPARC Solaris 2 by Mark Eichin
 * for Cygnus Support, July 1992.
 */

#include "tconfig.h"
#include "tsystem.h"
#include <fcntl.h> /* for creat() */
#include "coretypes.h"
#include "tm.h"

#if 0
#include "sparc/gmon.h"
#else
struct phdr {
  char *lpc;
  char *hpc;
  int ncnt;
};
#define HISTFRACTION 2
#define HISTCOUNTER unsigned short
#define HASHFRACTION 1
#define ARCDENSITY 2
#define MINARCS 50
struct tostruct {
  char *selfpc;
  long count;
  unsigned short link;
};
struct rawarc {
    unsigned long       raw_frompc;
    unsigned long       raw_selfpc;
    long                raw_count;
};
#define ROUNDDOWN(x,y)  (((x)/(y))*(y))
#define ROUNDUP(x,y)    ((((x)+(y)-1)/(y))*(y))

#endif

/* extern mcount() asm ("mcount"); */
/*extern*/ char *minbrk /* asm ("minbrk") */;

    /*
     *  froms is actually a bunch of unsigned shorts indexing tos
     */
static int              profiling = 3;
static unsigned short   *froms;
static struct tostruct  *tos = 0;
static long             tolimit = 0;
static char             *s_lowpc = 0;
static char             *s_highpc = 0;
static unsigned long    s_textsize = 0;

static int      ssiz;
static char     *sbuf;
static int      s_scale;
    /* see profil(2) where this is describe (incorrectly) */
#define         SCALE_1_TO_1    0x10000L

#define MSG "No space for profiling buffer(s)\n"

static void moncontrol (int);
extern void monstartup (char *, char *);
extern void _mcleanup (void);

void monstartup(char *lowpc, char *highpc)
{
    int                 monsize;
    char                *buffer;
    register int        o;

        /*
         *      round lowpc and highpc to multiples of the density we're using
         *      so the rest of the scaling (here and in gprof) stays in ints.
         */
    lowpc = (char *)
            ROUNDDOWN((unsigned long)lowpc, HISTFRACTION*sizeof(HISTCOUNTER));
    s_lowpc = lowpc;
    highpc = (char *)
            ROUNDUP((unsigned long)highpc, HISTFRACTION*sizeof(HISTCOUNTER));
    s_highpc = highpc;
    s_textsize = highpc - lowpc;
    monsize = (s_textsize / HISTFRACTION) + sizeof(struct phdr);
    buffer = sbrk( monsize );
    if ( buffer == (char *) -1 ) {
        write( 2 , MSG , sizeof(MSG) );
        return;
    }
    froms = (unsigned short *) sbrk( s_textsize / HASHFRACTION );
    if ( froms == (unsigned short *) -1 ) {
        write( 2 , MSG , sizeof(MSG) );
        froms = 0;
        return;
    }
    tolimit = s_textsize * ARCDENSITY / 100;
    if ( tolimit < MINARCS ) {
        tolimit = MINARCS;
    } else if ( tolimit > 65534 ) {
        tolimit = 65534;
    }
    tos = (struct tostruct *) sbrk( tolimit * sizeof( struct tostruct ) );
    if ( tos == (struct tostruct *) -1 ) {
        write( 2 , MSG , sizeof(MSG) );
        froms = 0;
        tos = 0;
        return;
    }
    minbrk = sbrk(0);
    tos[0].link = 0;
    sbuf = buffer;
    ssiz = monsize;
    ( (struct phdr *) buffer ) -> lpc = lowpc;
    ( (struct phdr *) buffer ) -> hpc = highpc;
    ( (struct phdr *) buffer ) -> ncnt = ssiz;
    monsize -= sizeof(struct phdr);
    if ( monsize <= 0 )
        return;
    o = highpc - lowpc;
    if( monsize < o )
#ifndef hp300
        s_scale = ( (float) monsize / o ) * SCALE_1_TO_1;
#else /* avoid floating point */
    {
        int quot = o / monsize;

        if (quot >= 0x10000)
                s_scale = 1;
        else if (quot >= 0x100)
                s_scale = 0x10000 / quot;
        else if (o >= 0x800000)
                s_scale = 0x1000000 / (o / (monsize >> 8));
        else
                s_scale = 0x1000000 / ((o << 8) / monsize);
    }
#endif
    else
        s_scale = SCALE_1_TO_1;
    moncontrol(1);
}

void
_mcleanup(void)
{
    int                 fd;
    int                 fromindex;
    int                 endfrom;
    char                *frompc;
    int                 toindex;
    struct rawarc       rawarc;
    char                *profdir;
    const char          *proffile;
    char                *progname;
    char                 buf[PATH_MAX];
    extern char        **___Argv;

    moncontrol(0);

    if ((profdir = getenv("PROFDIR")) != NULL) {
        /* If PROFDIR contains a null value, no profiling output is produced */
        if (*profdir == '\0') {
            return;
        }

        progname=strrchr(___Argv[0], '/');
        if (progname == NULL)
            progname=___Argv[0];
        else
            progname++;

        sprintf(buf, "%s/%ld.%s", profdir, (long) getpid(), progname);
        proffile = buf;
    } else {
        proffile = "gmon.out";
    }

    fd = creat( proffile, 0666 );
    if ( fd < 0 ) {
        perror( proffile );
        return;
    }
#   ifdef DEBUG
        fprintf( stderr , "[mcleanup] sbuf 0x%x ssiz %d\n" , sbuf , ssiz );
#   endif /* DEBUG */
    write( fd , sbuf , ssiz );
    endfrom = s_textsize / (HASHFRACTION * sizeof(*froms));
    for ( fromindex = 0 ; fromindex < endfrom ; fromindex++ ) {
        if ( froms[fromindex] == 0 ) {
            continue;
        }
        frompc = s_lowpc + (fromindex * HASHFRACTION * sizeof(*froms));
        for (toindex=froms[fromindex]; toindex!=0; toindex=tos[toindex].link) {
#           ifdef DEBUG
                fprintf( stderr ,
                        "[mcleanup] frompc 0x%x selfpc 0x%x count %d\n" ,
                        frompc , tos[toindex].selfpc , tos[toindex].count );
#           endif /* DEBUG */
            rawarc.raw_frompc = (unsigned long) frompc;
            rawarc.raw_selfpc = (unsigned long) tos[toindex].selfpc;
            rawarc.raw_count = tos[toindex].count;
            write( fd , &rawarc , sizeof rawarc );
        }
    }
    close( fd );
}

/*
 * The SPARC stack frame is only held together by the frame pointers
 * in the register windows. According to the SVR4 SPARC ABI
 * Supplement, Low Level System Information/Operating System
 * Interface/Software Trap Types, a type 3 trap will flush all of the
 * register windows to the stack, which will make it possible to walk
 * the frames and find the return addresses.
 *      However, it seems awfully expensive to incur a trap (system
 * call) for every function call. It turns out that "call" simply puts
 * the return address in %o7 expecting the "save" in the procedure to
 * shift it into %i7; this means that before the "save" occurs, %o7
 * contains the address of the call to mcount, and %i7 still contains
 * the caller above that. The asm mcount here simply saves those
 * registers in argument registers and branches to internal_mcount,
 * simulating a call with arguments.
 *      Kludges:
 *      1) the branch to internal_mcount is hard coded; it should be
 * possible to tell asm to use the assembler-name of a symbol.
 *      2) in theory, the function calling mcount could have saved %i7
 * somewhere and reused the register; in practice, I *think* this will
 * break longjmp (and maybe the debugger) but I'm not certain. (I take
 * some comfort in the knowledge that it will break the native mcount
 * as well.)
 *      3) if builtin_return_address worked, this could be portable.
 * However, it would really have to be optimized for arguments of 0
 * and 1 and do something like what we have here in order to avoid the
 * trap per function call performance hit. 
 *      4) the atexit and monsetup calls prevent this from simply
 * being a leaf routine that doesn't do a "save" (and would thus have
 * access to %o7 and %i7 directly) but the call to write() at the end
 * would have also prevented this.
 *
 * -- [eichin:19920702.1107EST]
 */

static void internal_mcount (char *, unsigned short *) __attribute__ ((used));

/* i7 == last ret, -> frompcindex */
/* o7 == current ret, -> selfpc */
/* Solaris 2 libraries use _mcount.  */
asm(".global _mcount; _mcount: mov %i7,%o1; mov %o7,%o0;b,a internal_mcount");
/* This is for compatibility with old versions of gcc which used mcount.  */
asm(".global mcount; mcount: mov %i7,%o1; mov %o7,%o0;b,a internal_mcount");

static void internal_mcount(char *selfpc, unsigned short *frompcindex)
{
        register struct tostruct        *top;
        register struct tostruct        *prevtop;
        register long                   toindex;
        static char already_setup;

        /*
         *      find the return address for mcount,
         *      and the return address for mcount's caller.
         */

        if(!already_setup) {
          extern char etext[];
          extern char _start[];
          extern char _init[];
          already_setup = 1;
          monstartup(_start < _init ? _start : _init, etext);
#ifdef USE_ONEXIT
          on_exit(_mcleanup, 0);
#else
          atexit(_mcleanup);
#endif
        }
        /*
         *      check that we are profiling
         *      and that we aren't recursively invoked.
         */
        if (profiling) {
                goto out;
        }
        profiling++;
        /*
         *      check that frompcindex is a reasonable pc value.
         *      for example:    signal catchers get called from the stack,
         *                      not from text space.  too bad.
         */
        frompcindex = (unsigned short *)((long)frompcindex - (long)s_lowpc);
        if ((unsigned long)frompcindex > s_textsize) {
                goto done;
        }
        frompcindex =
            &froms[((long)frompcindex) / (HASHFRACTION * sizeof(*froms))];
        toindex = *frompcindex;
        if (toindex == 0) {
                /*
                 *      first time traversing this arc
                 */
                toindex = ++tos[0].link;
                if (toindex >= tolimit) {
                        goto overflow;
                }
                *frompcindex = toindex;
                top = &tos[toindex];
                top->selfpc = selfpc;
                top->count = 1;
                top->link = 0;
                goto done;
        }
        top = &tos[toindex];
        if (top->selfpc == selfpc) {
                /*
                 *      arc at front of chain; usual case.
                 */
                top->count++;
                goto done;
        }
        /*
         *      have to go looking down chain for it.
         *      top points to what we are looking at,
         *      prevtop points to previous top.
         *      we know it is not at the head of the chain.
         */
        for (; /* goto done */; ) {
                if (top->link == 0) {
                        /*
                         *      top is end of the chain and none of the chain
                         *      had top->selfpc == selfpc.
                         *      so we allocate a new tostruct
                         *      and link it to the head of the chain.
                         */
                        toindex = ++tos[0].link;
                        if (toindex >= tolimit) {
                                goto overflow;
                        }
                        top = &tos[toindex];
                        top->selfpc = selfpc;
                        top->count = 1;
                        top->link = *frompcindex;
                        *frompcindex = toindex;
                        goto done;
                }
                /*
                 *      otherwise, check the next arc on the chain.
                 */
                prevtop = top;
                top = &tos[top->link];
                if (top->selfpc == selfpc) {
                        /*
                         *      there it is.
                         *      increment its count
                         *      move it to the head of the chain.
                         */
                        top->count++;
                        toindex = prevtop->link;
                        prevtop->link = top->link;
                        top->link = *frompcindex;
                        *frompcindex = toindex;
                        goto done;
                }

        }
done:
        profiling--;
        /* and fall through */
out:
        return;         /* normal return restores saved registers */

overflow:
        profiling++; /* halt further profiling */
#   define      TOLIMIT "mcount: tos overflow\n"
        write(2, TOLIMIT, sizeof(TOLIMIT));
        goto out;
}

/*
 * Control profiling
 *      profiling is what mcount checks to see if
 *      all the data structures are ready.
 */
static void moncontrol(int mode)
{
    if (mode) {
        /* start */
        profil((unsigned short *)(sbuf + sizeof(struct phdr)),
               ssiz - sizeof(struct phdr),
               (long)s_lowpc, s_scale);
        profiling = 0;
    } else {
        /* stop */
        profil((unsigned short *)0, 0, 0, 0);
        profiling = 3;
    }
}