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/*-

 * 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 [rescinded 22 July 1999]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;

    }

}