|
|
researchv10 Norman
/*
* machine-dependent code for
* looking in stack frames
* cray x-mp
*/
#include "defs.h"
#include "regs.h"
#include "sym.h"
#include "space.h"
#include "machine.h"
/*
* stack frame, relative to *b02
*/
#define F_PC 010 /* return pc */
#define F_AP 020 /* saved arg pointer */
#define F_FP 030 /* saved frame pointer */
/*
* return an address for a local variable
* no register vars, unfortunately, as we can't provide an address
* gn is the procedure; ln the local name
*/
localaddr(gn, ln)
char *gn, *ln;
{
WORD fp, ap;
extern WORD expv;
extern int expsp;
ADDR laddr();
if (gn) {
if (findrtn(gn) == 0)
error("function not found");
}
else {
findsym((WORD)atow(rget(PC)), INSTSP);
if (cursym == NULL)
error("function not found");
}
if (findframe(&fp, &ap) == 0)
error("stack frame not found");
if (ln == NULL) {
expsp = 0;
expv = fp;
return;
}
while (localsym()) {
if (strcmp(ln, cursym->y_name) != 0)
continue;
expv = laddr(cursym, fp, ap);
if (cursym->y_ltype == S_RSYM)
expsp = REGSP;
else
expsp = NOSP;
return;
}
error("bad local variable");
/* NOTREACHED */
}
/*
* print a stack traceback
* give locals if possible
*/
int maxargs = 20;
ctrace(modif)
char modif;
{
register ADDR fp, ap, callpc;
register int narg;
register int i;
if (adrflg) {
fp = adrval;
ap = watoba(atow(aget(fp+F_AP, CORF|DATASP)));
callpc = patoba(atow(aget(fp+F_PC, CORF|DATASP)));
} else {
ap = (ADDR)watoba(rtow(rget(A0+6)));
fp = (ADDR)watoba(rtow(rget(B00+2)));
callpc = (ADDR)rtow(rget(PC));
}
clrraddr();
while (cntval--) {
chkerr();
findsym(callpc, INSTSP);
if (cursym == NULL)
printf("?(");
else
printf("%s(", cursym->y_name);
narg = ltow(lget(ap, CORF|DATASP))&077; /* real size? */
for (i = 1; --narg >= 0 && i <= maxargs; i++) {
printf("%R", ltow(lget(ap + i * SZREG, CORF|DATASP)));
if (narg != 0)
printc(',');
}
if (narg >= 0)
printf(",...");
printf(") from %R\n", callpc);
if (modif == 'C')
locals(fp, ap);
callpc = patoba(atow(aget(fp + F_PC, CORF|DATASP)));
setraddr(fp);
ap = watoba(atow(aget(fp + F_AP, CORF|DATASP)));
fp = watoba(atow(aget(fp + F_FP, CORF|DATASP)));
if (fp == 0 || callpc == 0)
break;
}
clrraddr();
}
static
locals(fp, ap)
ADDR fp, ap;
{
WORD val;
register int sp;
ADDR laddr();
while (localsym()) {
sp = CORF | DATASP;
if (cursym->y_ltype == S_RSYM)
sp = CORF | REGSP;
val = ltow(lget(laddr(cursym, fp, ap), sp));
if (errflg == 0)
printf("%8t%s/%10t%R\n", cursym->y_name, val);
else {
printf("%8t%s/%10t?\n", cursym->y_name);
errflg = 0;
}
}
}
static ADDR
laddr(sp, fp, ap)
struct sym *sp;
ADDR fp, ap;
{
switch (sp->y_ltype) {
case S_STSYM:
return (sp->y_value);
case S_LSYM:
return (fp - sp->y_value);
case S_PSYM:
return (ap + sp->y_value);
case S_RSYM:
return (sp->y_value * SZREG);
}
error("bad local symbol");
/* NOTREACHED */
}
static int
findframe(fpp, app)
ADDR *fpp, *app;
{
#ifndef NOTDEF
error("no");
#else
register ADDR fp, ap, pc;
register int fl;
struct sym *svcur;
svcur = cursym;
fp = rtow(rget(FP));
ap = rtow(rget(AP));
pc = rtow(rget(PC));
if (errflg)
return (0);
clrraddr();
for (;;) {
findsym(pc, INSTSP);
if (cursym == svcur)
break;
if (cursym && strcmp(cursym->y_name, "start") == 0) {
clrraddr();
return (0);
}
fl = stow(sget((ADDR)fp + F_FLAGS, CORF|DATASP));
setraddr(fl, fp);
pc = atow(aget(fp + F_PC, CORF|DATASP));
ap = atow(aget(fp + F_AP, CORF|DATASP));
fp = atow(aget(fp + F_FP + SALIGN(fl), CORF|DATASP));
/* sigtramp? */
if (errflg) {
clrraddr();
return (0);
}
}
*fpp = fp;
*app = ap;
return (1);
#endif
}
/*
* set addresses for saved registers for this frame
*/
static
setraddr(fp)
register ADDR fp;
{
#if NOTDEF
register int r;
register int i;
extern ADDR raddr[];
mask &= FFREGS;
for (r = 0, i = 0; mask; r++)
if (mask & (1 << r)) {
if (MINREG <= r && r <= MAXREG)
raddr[r - MINREG] = fp + F_REGS +
i * SZREG;
i++;
mask &=~ (1 << r);
}
#endif
}
static
clrraddr()
{
register int i;
extern ADDR raddr[];
for (i = 0; i <= MAXREG - MINREG; i++)
raddr[i] = 0;
}
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.