ref: 54c94a93f0c9de18f05441eb6ee46d813843c396
dir: /sys/src/libmach/machdata.c/
/*
* Debugger utilities shared by at least two architectures
*/
#include <u.h>
#include <libc.h>
#include <bio.h>
#include <mach.h>
#define STARTSYM "_main"
#define PROFSYM "_mainp"
#define FRAMENAME ".frame"
extern Machdata mipsmach;
int asstype = AMIPS; /* disassembler type */
Machdata *machdata; /* machine-dependent functions */
int
localaddr(Map *map, char *fn, char *var, uvlong *r, Rgetter rget)
{
Symbol s;
uvlong fp, pc, sp, link;
if (!lookup(fn, 0, &s)) {
werrstr("function not found");
return -1;
}
pc = rget(map, mach->pc);
sp = rget(map, mach->sp);
if(mach->link)
link = rget(map, mach->link);
else
link = 0;
fp = machdata->findframe(map, s.value, pc, sp, link);
if (fp == 0) {
werrstr("stack frame not found");
return -1;
}
if (!var || !var[0]) {
*r = fp;
return 1;
}
if (findlocal(&s, var, &s) == 0) {
werrstr("local variable not found");
return -1;
}
switch (s.class) {
case CAUTO:
*r = fp - s.value;
break;
case CPARAM: /* assume address size is stack width */
*r = fp + s.value + mach->szaddr;
break;
default:
werrstr("local variable not found: %d", s.class);
return -1;
}
return 1;
}
/*
* Print value v as s.name[+offset] if possible, or just v.
*/
int
symoff(char *buf, int n, uvlong v, int space)
{
Symbol s;
int r;
long delta;
r = delta = 0; /* to shut compiler up */
if (v) {
r = findsym(v, space, &s);
if (r)
delta = v-s.value;
if (delta < 0)
delta = -delta;
}
if (v == 0 || r == 0)
return snprint(buf, n, "%llux", v);
if (s.type != 't' && s.type != 'T' && delta >= 4096)
return snprint(buf, n, "%llux", v);
else if (delta)
return snprint(buf, n, "%s+%lux", s.name, delta);
else
return snprint(buf, n, "%s", s.name);
}
/*
* Format floating point registers
*
* Register codes in format field:
* 'X' - print as 32-bit hexadecimal value
* 'F' - 64-bit double register when modif == 'F'; else 32-bit single reg
* 'f' - 32-bit ieee float
* '8' - big endian 80-bit ieee extended float
* '3' - little endian 80-bit ieee extended float with hole in bytes 8&9
*/
int
fpformat(Map *map, Reglist *rp, char *buf, int n, int modif)
{
char reg[12];
ulong r;
switch(rp->rformat)
{
case 'X':
if (get4(map, rp->roffs, &r) < 0)
return -1;
snprint(buf, n, "%lux", r);
break;
case 'F': /* first reg of double reg pair */
if (modif == 'F')
if ((rp->rformat=='F') || (((rp+1)->rflags&RFLT) && (rp+1)->rformat == 'f')) {
if (get1(map, rp->roffs, (uchar *)reg, 8) < 0)
return -1;
machdata->dftos(buf, n, reg);
if (rp->rformat == 'F')
return 1;
return 2;
}
/* treat it like 'f' */
if (get1(map, rp->roffs, (uchar *)reg, 4) < 0)
return -1;
machdata->sftos(buf, n, reg);
break;
case 'f': /* 32 bit float */
if (get1(map, rp->roffs, (uchar *)reg, 4) < 0)
return -1;
machdata->sftos(buf, n, reg);
break;
case '3': /* little endian ieee 80 with hole in bytes 8&9 */
if (get1(map, rp->roffs, (uchar *)reg, 10) < 0)
return -1;
memmove(reg+10, reg+8, 2); /* open hole */
memset(reg+8, 0, 2); /* fill it */
leieee80ftos(buf, n, reg);
break;
case '8': /* big-endian ieee 80 */
if (get1(map, rp->roffs, (uchar *)reg, 10) < 0)
return -1;
beieee80ftos(buf, n, reg);
break;
default: /* unknown */
break;
}
return 1;
}
char *
_hexify(char *buf, ulong p, int zeros)
{
ulong d;
d = p/16;
if(d)
buf = _hexify(buf, d, zeros-1);
else
while(zeros--)
*buf++ = '0';
*buf++ = "0123456789abcdef"[p&0x0f];
return buf;
}
/*
* These routines assume that if the number is representable
* in IEEE floating point, it will be representable in the native
* double format. Naive but workable, probably.
*/
int
ieeedftos(char *buf, int n, ulong h, ulong l)
{
double fr;
int exp;
if (n <= 0)
return 0;
if(h & (1L<<31)){
*buf++ = '-';
h &= ~(1L<<31);
}else
*buf++ = ' ';
n--;
if(l == 0 && h == 0)
return snprint(buf, n, "0.");
exp = (h>>20) & ((1L<<11)-1L);
if(exp == 0)
return snprint(buf, n, "DeN(%.8lux%.8lux)", h, l);
if(exp == ((1L<<11)-1L)){
if(l==0 && (h&((1L<<20)-1L)) == 0)
return snprint(buf, n, "Inf");
else
return snprint(buf, n, "NaN(%.8lux%.8lux)", h&((1L<<20)-1L), l);
}
exp -= (1L<<10) - 2L;
fr = l & ((1L<<16)-1L);
fr /= 1L<<16;
fr += (l>>16) & ((1L<<16)-1L);
fr /= 1L<<16;
fr += (h & (1L<<20)-1L) | (1L<<20);
fr /= 1L<<21;
fr = ldexp(fr, exp);
return snprint(buf, n, "%.18g", fr);
}
int
ieeesftos(char *buf, int n, ulong h)
{
double fr;
int exp;
if (n <= 0)
return 0;
if(h & (1L<<31)){
*buf++ = '-';
h &= ~(1L<<31);
}else
*buf++ = ' ';
n--;
if(h == 0)
return snprint(buf, n, "0.");
exp = (h>>23) & ((1L<<8)-1L);
if(exp == 0)
return snprint(buf, n, "DeN(%.8lux)", h);
if(exp == ((1L<<8)-1L)){
if((h&((1L<<23)-1L)) == 0)
return snprint(buf, n, "Inf");
else
return snprint(buf, n, "NaN(%.8lux)", h&((1L<<23)-1L));
}
exp -= (1L<<7) - 2L;
fr = (h & ((1L<<23)-1L)) | (1L<<23);
fr /= 1L<<24;
fr = ldexp(fr, exp);
return snprint(buf, n, "%.9g", fr);
}
int
beieeesftos(char *buf, int n, void *s)
{
return ieeesftos(buf, n, beswal(*(ulong*)s));
}
int
beieeedftos(char *buf, int n, void *s)
{
return ieeedftos(buf, n, beswal(*(ulong*)s), beswal(((ulong*)(s))[1]));
}
int
leieeesftos(char *buf, int n, void *s)
{
return ieeesftos(buf, n, leswal(*(ulong*)s));
}
int
leieeedftos(char *buf, int n, void *s)
{
return ieeedftos(buf, n, leswal(((ulong*)(s))[1]), leswal(*(ulong*)s));
}
/* packed in 12 bytes, with s[2]==s[3]==0; mantissa starts at s[4]*/
int
beieee80ftos(char *buf, int n, void *s)
{
uchar *reg = (uchar*)s;
int i;
ulong x;
uchar ieee[8+8]; /* room for slop */
uchar *p, *q;
memset(ieee, 0, sizeof(ieee));
/* sign */
if(reg[0] & 0x80)
ieee[0] |= 0x80;
/* exponent */
x = ((reg[0]&0x7F)<<8) | reg[1];
if(x == 0) /* number is ±0 */
goto done;
if(x == 0x7FFF){
if(memcmp(reg+4, ieee+1, 8) == 0){ /* infinity */
x = 2047;
}else{ /* NaN */
x = 2047;
ieee[7] = 0x1; /* make sure */
}
ieee[0] |= x>>4;
ieee[1] |= (x&0xF)<<4;
goto done;
}
x -= 0x3FFF; /* exponent bias */
x += 1023;
if(x >= (1<<11) || ((reg[4]&0x80)==0 && x!=0))
return snprint(buf, n, "not in range");
ieee[0] |= x>>4;
ieee[1] |= (x&0xF)<<4;
/* mantissa */
p = reg+4;
q = ieee+1;
for(i=0; i<56; i+=8, p++, q++){ /* move one byte */
x = (p[0]&0x7F) << 1;
if(p[1] & 0x80)
x |= 1;
q[0] |= x>>4;
q[1] |= (x&0xF)<<4;
}
done:
return beieeedftos(buf, n, (void*)ieee);
}
int
leieee80ftos(char *buf, int n, void *s)
{
int i;
char *cp;
char b[12];
cp = (char*) s;
for(i=0; i<12; i++)
b[11-i] = *cp++;
return beieee80ftos(buf, n, b);
}
int
cisctrace(Map *map, uvlong pc, uvlong sp, uvlong link, Tracer trace)
{
Symbol s;
int found, i;
uvlong opc, moved;
USED(link);
i = 0;
opc = 0;
while(pc && opc != pc) {
moved = pc2sp(pc);
if (moved == ~0)
break;
found = findsym(pc, CTEXT, &s);
if (!found)
break;
if(strcmp(STARTSYM, s.name) == 0 || strcmp(PROFSYM, s.name) == 0)
break;
sp += moved;
opc = pc;
if (geta(map, sp, &pc) < 0)
break;
(*trace)(map, pc, sp, &s);
sp += mach->szaddr; /*assumes address size = stack width*/
if(++i > 40)
break;
}
if(i == 0)
werrstr("no SP for PC %#llux", pc);
return i;
}
int
risctrace(Map *map, uvlong pc, uvlong sp, uvlong link, Tracer trace)
{
int i;
Symbol s, f;
uvlong oldpc;
i = 0;
while(findsym(pc, CTEXT, &s)) {
if(strcmp(STARTSYM, s.name) == 0 || strcmp(PROFSYM, s.name) == 0)
break;
if(pc == s.value) /* at first instruction */
f.value = 0;
else if(findlocal(&s, FRAMENAME, &f) == 0)
break;
oldpc = pc;
if(s.type == 'L' || s.type == 'l' || pc <= s.value+mach->pcquant)
pc = link;
else
if (geta(map, sp, &pc) < 0)
break;
if(pc == 0 || (pc == oldpc && f.value == 0))
break;
sp += f.value;
(*trace)(map, pc-8, sp, &s);
if(++i > 40)
break;
}
if(i == 0)
werrstr("no SP for PC %#llux", pc);
return i;
}
uvlong
ciscframe(Map *map, uvlong addr, uvlong pc, uvlong sp, uvlong link)
{
Symbol s;
uvlong moved;
USED(link);
for(;;) {
moved = pc2sp(pc);
if (moved == ~0)
break;
sp += moved;
findsym(pc, CTEXT, &s);
if (addr == s.value)
return sp;
if (geta(map, sp, &pc) < 0)
break;
sp += mach->szaddr; /*assumes sizeof(addr) = stack width*/
}
return 0;
}
uvlong
riscframe(Map *map, uvlong addr, uvlong pc, uvlong sp, uvlong link)
{
Symbol s, f;
while (findsym(pc, CTEXT, &s)) {
if(strcmp(STARTSYM, s.name) == 0 || strcmp(PROFSYM, s.name) == 0)
break;
if(pc == s.value) /* at first instruction */
f.value = 0;
else
if(findlocal(&s, FRAMENAME, &f) == 0)
break;
sp += f.value;
if (s.value == addr)
return sp;
if (s.type == 'L' || s.type == 'l' || pc-s.value <= mach->szaddr*2)
pc = link;
else
if (geta(map, sp-f.value, &pc) < 0)
break;
}
return 0;
}