[gcc.git] / 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 [rescinded 22 July 1999]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 "config.h"
#include "system.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	PARAMS ((int));
extern void monstartup	PARAMS ((char *, char *));
extern void _mcleanup	PARAMS ((void));

void 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);
}

void
_mcleanup()
{
    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, 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 PARAMS ((char *, unsigned short *)) ATTRIBUTE_UNUSED;

/* 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(selfpc, frompcindex)
	register char			*selfpc;
	register 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[];
	  already_setup = 1;
	  monstartup(0, (char *)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(mode)
    int mode;
{
    if (mode) {
	/* start */
	profil((unsigned short *)(sbuf + sizeof(struct phdr)),
	       ssiz - sizeof(struct phdr),
	       (int)s_lowpc, s_scale);
	profiling = 0;
    } else {
	/* stop */
	profil((unsigned short *)0, 0, 0, 0);
	profiling = 3;
    }
}
Commit	Line	Data
638e2294 RS	1	/*-
	2	* Copyright (c) 1991 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.
a8196924	13	* 3. [rescinded 22 July 1999]
638e2294 RS	14	* 4. Neither the name of the University nor the names of its contributors
	15	* may be used to endorse or promote products derived from this software
	16	* without specific prior written permission.
	17	*
	18	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	19	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	20	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	21	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	22	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	23	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	24	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	25	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	26	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	27	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	28	* SUCH DAMAGE.
	29	*/
	30
	31	/* Mangled into a form that works on Sparc Solaris 2 by Mark Eichin
	32	* for Cygnus Support, July 1992.
	33	*/
	34
3bb5de61 KG	35	#include "config.h"
3bb5de61 KG	36	#include "system.h"
638e2294 RS	37
638e2294 RS	38	#if 0
f1c7021e	39	#include "sparc/gmon.h"
638e2294 RS	40	#else
	41	struct phdr {
	42	char *lpc;
	43	char *hpc;
	44	int ncnt;
	45	};
	46	#define HISTFRACTION 2
	47	#define HISTCOUNTER unsigned short
	48	#define HASHFRACTION 1
	49	#define ARCDENSITY 2
	50	#define MINARCS 50
	51	struct tostruct {
	52	char *selfpc;
	53	long count;
	54	unsigned short link;
	55	};
	56	struct rawarc {
	57	unsigned long raw_frompc;
	58	unsigned long raw_selfpc;
	59	long raw_count;
	60	};
	61	#define ROUNDDOWN(x,y) (((x)/(y))*(y))
	62	#define ROUNDUP(x,y) ((((x)+(y)-1)/(y))*(y))
	63
	64	#endif
	65
	66	/* extern mcount() asm ("mcount"); */
	67	/extern/ char minbrk / asm ("minbrk") */;
	68
	69	/*
	70	* froms is actually a bunch of unsigned shorts indexing tos
	71	*/
	72	static int profiling = 3;
	73	static unsigned short *froms;
	74	static struct tostruct *tos = 0;
	75	static long tolimit = 0;
	76	static char *s_lowpc = 0;
	77	static char *s_highpc = 0;
	78	static unsigned long s_textsize = 0;
	79
	80	static int ssiz;
	81	static char *sbuf;
	82	static int s_scale;
	83	/* see profil(2) where this is describe (incorrectly) */
	84	#define SCALE_1_TO_1 0x10000L
	85
	86	#define MSG "No space for profiling buffer(s)\n"
	87
f6da8bc3 KG	88	static void moncontrol PARAMS ((int));
	89	extern void monstartup PARAMS ((char , char ));
	90	extern void _mcleanup PARAMS ((void));
9870475c JL	91
9870475c JL	92	void monstartup(lowpc, highpc)
638e2294 RS	93	char *lowpc;
	94	char *highpc;
	95	{
	96	int monsize;
	97	char *buffer;
	98	register int o;
	99
	100	/*
	101	* round lowpc and highpc to multiples of the density we're using
	102	* so the rest of the scaling (here and in gprof) stays in ints.
	103	*/
	104	lowpc = (char *)
	105	ROUNDDOWN((unsigned)lowpc, HISTFRACTION*sizeof(HISTCOUNTER));
	106	s_lowpc = lowpc;
	107	highpc = (char *)
	108	ROUNDUP((unsigned)highpc, HISTFRACTION*sizeof(HISTCOUNTER));
	109	s_highpc = highpc;
	110	s_textsize = highpc - lowpc;
	111	monsize = (s_textsize / HISTFRACTION) + sizeof(struct phdr);
	112	buffer = sbrk( monsize );
	113	if ( buffer == (char *) -1 ) {
	114	write( 2 , MSG , sizeof(MSG) );
	115	return;
	116	}
	117	froms = (unsigned short *) sbrk( s_textsize / HASHFRACTION );
	118	if ( froms == (unsigned short *) -1 ) {
	119	write( 2 , MSG , sizeof(MSG) );
	120	froms = 0;
	121	return;
	122	}
	123	tolimit = s_textsize * ARCDENSITY / 100;
	124	if ( tolimit < MINARCS ) {
	125	tolimit = MINARCS;
	126	} else if ( tolimit > 65534 ) {
	127	tolimit = 65534;
	128	}
	129	tos = (struct tostruct ) sbrk( tolimit sizeof( struct tostruct ) );
	130	if ( tos == (struct tostruct *) -1 ) {
	131	write( 2 , MSG , sizeof(MSG) );
	132	froms = 0;
	133	tos = 0;
	134	return;
	135	}
	136	minbrk = sbrk(0);
	137	tos[0].link = 0;
	138	sbuf = buffer;
	139	ssiz = monsize;
	140	( (struct phdr *) buffer ) -> lpc = lowpc;
	141	( (struct phdr *) buffer ) -> hpc = highpc;
	142	( (struct phdr *) buffer ) -> ncnt = ssiz;
	143	monsize -= sizeof(struct phdr);
	144	if ( monsize <= 0 )
	145	return;
	146	o = highpc - lowpc;
	147	if( monsize < o )
	148	#ifndef hp300
	149	s_scale = ( (float) monsize / o ) * SCALE_1_TO_1;
	150	#else /* avoid floating point */
	151	{
	152	int quot = o / monsize;
	153
	154	if (quot >= 0x10000)
	155	s_scale = 1;
	156	else if (quot >= 0x100)
157	s_scale = 0x10000 / quot;
158	else if (o >= 0x800000)
159	s_scale = 0x1000000 / (o / (monsize >> 8));
160	else
161	s_scale = 0x1000000 / ((o << 8) / monsize);
162	}
163	#endif
164	else
165	s_scale = SCALE_1_TO_1;
166	moncontrol(1);
167	}
168
6156580d	169	void
638e2294 RS	170	_mcleanup()
	171	{
	172	int fd;
	173	int fromindex;
	174	int endfrom;
	175	char *frompc;
	176	int toindex;
	177	struct rawarc rawarc;
6156580d	178	char *profdir;
3bb5de61	179	const char *proffile;
6156580d JW	180	char *progname;
	181	char buf[PATH_MAX];
	182	extern char **___Argv;
638e2294 RS	183
638e2294 RS	184	moncontrol(0);
6156580d JW	185
	186	if ((profdir = getenv("PROFDIR")) != NULL) {
	187	/* If PROFDIR contains a null value, no profiling output is produced */
	188	if (*profdir == '\0') {
	189	return;
	190	}
	191
	192	progname=strrchr(___Argv[0], '/');
	193	if (progname == NULL)
	194	progname=___Argv[0];
	195	else
	196	progname++;
	197
9870475c	198	sprintf(buf, "%s/%ld.%s", profdir, getpid(), progname);
6156580d JW	199	proffile = buf;
	200	} else {
	201	proffile = "gmon.out";
	202	}
	203
	204	fd = creat( proffile, 0666 );
638e2294	205	if ( fd < 0 ) {
6156580d	206	perror( proffile );
638e2294 RS	207	return;
	208	}
	209	# ifdef DEBUG
	210	fprintf( stderr , "[mcleanup] sbuf 0x%x ssiz %d\n" , sbuf , ssiz );
	211	# endif DEBUG
	212	write( fd , sbuf , ssiz );
	213	endfrom = s_textsize / (HASHFRACTION * sizeof(*froms));
	214	for ( fromindex = 0 ; fromindex < endfrom ; fromindex++ ) {
	215	if ( froms[fromindex] == 0 ) {
	216	continue;
	217	}
	218	frompc = s_lowpc + (fromindex * HASHFRACTION * sizeof(*froms));
	219	for (toindex=froms[fromindex]; toindex!=0; toindex=tos[toindex].link) {
	220	# ifdef DEBUG
	221	fprintf( stderr ,
	222	"[mcleanup] frompc 0x%x selfpc 0x%x count %d\n" ,
	223	frompc , tos[toindex].selfpc , tos[toindex].count );
	224	# endif DEBUG
	225	rawarc.raw_frompc = (unsigned long) frompc;
	226	rawarc.raw_selfpc = (unsigned long) tos[toindex].selfpc;
	227	rawarc.raw_count = tos[toindex].count;
	228	write( fd , &rawarc , sizeof rawarc );
	229	}
	230	}
	231	close( fd );
	232	}
	233
	234	/*
	235	* The Sparc stack frame is only held together by the frame pointers
	236	* in the register windows. According to the SVR4 SPARC ABI
	237	* Supplement, Low Level System Information/Operating System
	238	* Interface/Software Trap Types, a type 3 trap will flush all of the
	239	* register windows to the stack, which will make it possible to walk
	240	* the frames and find the return addresses.
	241	* However, it seems awfully expensive to incur a trap (system
	242	* call) for every function call. It turns out that "call" simply puts
	243	* the return address in %o7 expecting the "save" in the procedure to
	244	* shift it into %i7; this means that before the "save" occurs, %o7
	245	* contains the address of the call to mcount, and %i7 still contains
	246	* the caller above that. The asm mcount here simply saves those
	247	* registers in argument registers and branches to internal_mcount,
	248	* simulating a call with arguments.
	249	* Kludges:
	250	* 1) the branch to internal_mcount is hard coded; it should be
	251	* possible to tell asm to use the assembler-name of a symbol.
	252	* 2) in theory, the function calling mcount could have saved %i7
	253	* somewhere and reused the register; in practice, I think this will
	254	* break longjmp (and maybe the debugger) but I'm not certain. (I take
	255	* some comfort in the knowledge that it will break the native mcount
	256	* as well.)
	257	* 3) if builtin_return_address worked, this could be portable.
	258	* However, it would really have to be optimized for arguments of 0
	259	* and 1 and do something like what we have here in order to avoid the
	260	* trap per function call performance hit.
	261	* 4) the atexit and monsetup calls prevent this from simply
	262	* being a leaf routine that doesn't do a "save" (and would thus have
	263	* access to %o7 and %i7 directly) but the call to write() at the end
	264	* would have also prevented this.
	265	*
	266	* -- [eichin:19920702.1107EST]
	267	*/
	268
f6da8bc3	269	static void internal_mcount PARAMS ((char , unsigned short )) ATTRIBUTE_UNUSED;
3bb5de61	270
638e2294 RS	271	/* i7 == last ret, -> frompcindex */
638e2294 RS	272	/* o7 == current ret, -> selfpc */
e6381520 RK	273	/* Solaris 2 libraries use _mcount. */
	274	asm(".global _mcount; _mcount: mov %i7,%o1; mov %o7,%o0;b,a internal_mcount");
	275	/* This is for compatibility with old versions of gcc which used mcount. */
638e2294 RS	276	asm(".global mcount; mcount: mov %i7,%o1; mov %o7,%o0;b,a internal_mcount");
638e2294 RS	277
9870475c	278	static void internal_mcount(selfpc, frompcindex)
638e2294 RS	279	register char *selfpc;
	280	register unsigned short *frompcindex;
	281	{
638e2294 RS	282	register struct tostruct *top;
	283	register struct tostruct *prevtop;
	284	register long toindex;
	285	static char already_setup;
	286
	287	/*
	288	* find the return address for mcount,
	289	* and the return address for mcount's caller.
	290	*/
	291
	292	if(!already_setup) {
3bb5de61	293	extern char etext[];
638e2294	294	already_setup = 1;
3bb5de61	295	monstartup(0, (char *)etext);
638e2294 RS	296	#ifdef USE_ONEXIT
	297	on_exit(_mcleanup, 0);
	298	#else
	299	atexit(_mcleanup);
	300	#endif
	301	}
	302	/*
	303	* check that we are profiling
	304	* and that we aren't recursively invoked.
	305	*/
	306	if (profiling) {
	307	goto out;
	308	}
	309	profiling++;
	310	/*
	311	* check that frompcindex is a reasonable pc value.
	312	* for example: signal catchers get called from the stack,
	313	* not from text space. too bad.
	314	*/
	315	frompcindex = (unsigned short *)((long)frompcindex - (long)s_lowpc);
	316	if ((unsigned long)frompcindex > s_textsize) {
	317	goto done;
	318	}
	319	frompcindex =
	320	&froms[((long)frompcindex) / (HASHFRACTION * sizeof(*froms))];
	321	toindex = *frompcindex;
	322	if (toindex == 0) {
	323	/*
	324	* first time traversing this arc
	325	*/
	326	toindex = ++tos[0].link;
	327	if (toindex >= tolimit) {
	328	goto overflow;
	329	}
	330	*frompcindex = toindex;
	331	top = &tos[toindex];
	332	top->selfpc = selfpc;
	333	top->count = 1;
	334	top->link = 0;
	335	goto done;
	336	}
	337	top = &tos[toindex];
	338	if (top->selfpc == selfpc) {
	339	/*
	340	* arc at front of chain; usual case.
	341	*/
	342	top->count++;
	343	goto done;
	344	}
	345	/*
	346	* have to go looking down chain for it.
	347	* top points to what we are looking at,
	348	* prevtop points to previous top.
	349	* we know it is not at the head of the chain.
	350	*/
	351	for (; /* goto done */; ) {
	352	if (top->link == 0) {
	353	/*
	354	* top is end of the chain and none of the chain
	355	* had top->selfpc == selfpc.
	356	* so we allocate a new tostruct
	357	* and link it to the head of the chain.
	358	*/
	359	toindex = ++tos[0].link;
360	if (toindex >= tolimit) {
361	goto overflow;
362	}
363	top = &tos[toindex];
364	top->selfpc = selfpc;
365	top->count = 1;
366	top->link = *frompcindex;
367	*frompcindex = toindex;
368	goto done;
369	}
370	/*
371	* otherwise, check the next arc on the chain.
372	*/
373	prevtop = top;
374	top = &tos[top->link];
375	if (top->selfpc == selfpc) {
376	/*
377	* there it is.
378	* increment its count
379	* move it to the head of the chain.
380	*/
381	top->count++;
382	toindex = prevtop->link;
383	prevtop->link = top->link;
384	top->link = *frompcindex;
385	*frompcindex = toindex;
386	goto done;
387	}
388
389	}
390	done:
391	profiling--;
392	/* and fall through */
393	out:
394	return; /* normal return restores saved registers */
395
396	overflow:
397	profiling++; /* halt further profiling */
398	# define TOLIMIT "mcount: tos overflow\n"
399	write(2, TOLIMIT, sizeof(TOLIMIT));
400	goto out;
401	}
402
403	/*
404	* Control profiling
405	* profiling is what mcount checks to see if
406	* all the data structures are ready.
407	*/
9870475c	408	static void moncontrol(mode)
638e2294 RS	409	int mode;
	410	{
	411	if (mode) {
	412	/* start */
	413	profil((unsigned short *)(sbuf + sizeof(struct phdr)),
	414	ssiz - sizeof(struct phdr),
	415	(int)s_lowpc, s_scale);
	416	profiling = 0;
	417	} else {
	418	/* stop */
	419	profil((unsigned short *)0, 0, 0, 0);
	420	profiling = 3;
	421	}
	422	}