source: trunk/third/gcc/gmon.c @ 8834

/*-
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 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.
 */

#ifndef lint
static char sccsid[] = "@(#)gmon.c      5.3 (Berkeley) 5/22/91";
#endif /* not lint */

#if 0
#include <unistd.h>

#endif
#ifdef DEBUG
#include <stdio.h>
#endif

#include "gmon.h"

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

#ifdef __alpha
extern char *sbrk ();
#endif

    /*
     *  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"

monstartup(lowpc, highpc)
    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)lowpc, HISTFRACTION*sizeof(HISTCOUNTER));
    s_lowpc = lowpc;
    highpc = (char *)
            ROUNDUP((unsigned)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);
}

_mcleanup()
{
    int                 fd;
    int                 fromindex;
    int                 endfrom;
    char                *frompc;
    int                 toindex;
    struct rawarc       rawarc;

    moncontrol(0);
    fd = creat( "gmon.out" , 0666 );
    if ( fd < 0 ) {
        perror( "mcount: gmon.out" );
        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 );
}

mcount()
{
        register char                   *selfpc;
        register unsigned short         *frompcindex;
        register struct tostruct        *top;
        register struct tostruct        *prevtop;
        register long                   toindex;

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

        /* selfpc = pc pushed by mcount call.
           This identifies the function that was just entered.  */
        selfpc = (void *) __builtin_return_address (0);
        /* frompcindex = pc in preceding frame.
           This identifies the caller of the function just entered.  */
        frompcindex = (void *) __builtin_return_address (1);
        /*
         *      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.
 */
moncontrol(mode)
    int mode;
{
    if (mode) {
        /* start */
        profil(sbuf + sizeof(struct phdr), ssiz - sizeof(struct phdr),
                (int)s_lowpc, s_scale);
        profiling = 0;
    } else {
        /* stop */
        profil((char *)0, 0, 0, 0);
        profiling = 3;
    }
}