4.1cBSD/usr/src/lib/libc/csu/gmon.c
static char *sccsid = "@(#)gmon.c 4.10 (Berkeley) 1/14/83";
#ifdef DEBUG
#include <stdio.h>
#endif DEBUG
#include "gmon.h"
/*
* 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 char *minsbrk = 0;
static int ssiz;
static int *sbuf;
#define MSG "No space for monitor buffer(s)\n"
monstartup(lowpc, highpc)
char *lowpc;
char *highpc;
{
int monsize;
char *buffer;
char *sbrk();
/*
* 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;
}
minsbrk = sbrk(0);
tos[0].link = 0;
monitor( lowpc , highpc , buffer , monsize , tolimit );
/*
* profiling is what mcount checks to see if
* all the data structures are ready!!!
*/
profiling = 0;
}
_mcleanup()
{
int fd;
int fromindex;
int endfrom;
char *frompc;
int toindex;
struct rawarc rawarc;
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 );
}
asm(".text");
asm("#the beginning of mcount()");
asm(".data");
mcount()
{
register char *selfpc; /* r11 => r5 */
register unsigned short *frompcindex; /* r10 => r4 */
register struct tostruct *top; /* r9 => r3 */
register struct tostruct *prevtop; /* r8 => r2 */
register long toindex; /* r7 => r1 */
#ifdef lint
selfpc = (char *)0;
frompcindex = 0;
#else not lint
/*
* find the return address for mcount,
* and the return address for mcount's caller.
*/
asm(" .text"); /* make sure we're in text space */
asm(" movl (sp), r11"); /* selfpc = ... (jsb frame) */
asm(" movl 16(fp), r10"); /* frompcindex = (calls frame) */
#endif not lint
/*
* 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:
asm(" rsb");
overflow:
profiling++; /* halt further profiling */
# define TOLIMIT "mcount: tos overflow\n"
write(2, TOLIMIT, sizeof(TOLIMIT));
goto out;
}
asm(".text");
asm("#the end of mcount()");
asm(".data");
/*VARARGS1*/
monitor( lowpc , highpc , buf , bufsiz , nfunc )
char *lowpc;
char *highpc;
int *buf, bufsiz;
int nfunc; /* not used, available for compatability only */
{
register o;
if ( lowpc == 0 ) {
profiling++; /* halt profiling */
profil( (char *) 0 , 0 , 0 , 0 );
_mcleanup();
return;
}
sbuf = buf;
ssiz = bufsiz;
( (struct phdr *) buf ) -> lpc = lowpc;
( (struct phdr *) buf ) -> hpc = highpc;
( (struct phdr *) buf ) -> ncnt = ssiz;
o = sizeof(struct phdr);
buf = (int *) ( ( (int) buf ) + o );
bufsiz -= o;
if ( bufsiz <= 0 )
return;
o = ( ( (char *) highpc - (char *) lowpc) );
if( bufsiz < o )
o = ( (float) bufsiz / o ) * 65536;
else
o = 65536;
profil( buf , bufsiz , lowpc , o );
}
/*
* This is a stub for the "brk" system call, which we want to
* catch so that it will not deallocate our data space.
* (of which the program is not aware)
*/
extern char *curbrk;
brk(addr)
char *addr;
{
if (addr < minsbrk)
addr = minsbrk;
asm(" chmk $17");
asm(" jcc 1f");
asm(" jmp cerror");
asm("1:");
curbrk = addr;
return (0);
}