int
dwarfpctoline(Dwarf *d, DwarfSym *proc, ulong pc, char **file, char **function, ulong *line)
{
char *cdir;
uchar *prog, *opcount, *end, *dirs;
ulong off, unit, len, vers, x, start, lastline;
int i, first, firstline, op, a, l, quantum, isstmt, linebase, linerange, opcodebase, nf;
char *files, *s;
DwarfBuf b;
DwarfSym sym;
State emit, cur, reset;
char **f, **newf;
f = nil;
memset(proc, 0, sizeof(*proc));
int runit = dwarfaddrtounit(d, pc, &unit);
if (runit < 0)
return -1;
int rtag = dwarflookuptag(d, unit, TagCompileUnit, &sym);
if (rtag < 0)
return -1;
if(!sym.attrs.have.stmtlist){
werrstr("no line mapping information for 0x%x", pc);
return -1;
}
off = sym.attrs.stmtlist;
if(off >= d->line.len){
werrstr("bad stmtlist");
goto bad;
}
if(trace) werrstr("unit 0x%x stmtlist 0x%x", unit, sym.attrs.stmtlist);
memset(&b, 0, sizeof b);
b.d = d;
b.p = d->line.data + off;
b.ep = b.p + d->line.len;
b.addrsize = sym.b.addrsize; /* should i get this from somewhere else? */
len = dwarfget4(&b);
if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){
werrstr("bad len");
goto bad;
}
b.ep = b.p+len;
vers = dwarfget2(&b);
if(vers != 2){
werrstr("bad dwarf version 0x%x", vers);
return -1;
}
len = dwarfget4(&b);
if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){
werrstr("another bad len");
goto bad;
}
prog = b.p+len;
quantum = dwarfget1(&b);
isstmt = dwarfget1(&b);
linebase = (schar)dwarfget1(&b);
linerange = (schar)dwarfget1(&b);
opcodebase = dwarfget1(&b);
opcount = b.p-1;
dwarfgetnref(&b, opcodebase-1);
if(b.p == nil){
werrstr("bad opcode chart");
goto bad;
}
/* just skip the files and dirs for now; we'll come back */
dirs = b.p;
while (b.p && *b.p)
dwarfgetstring(&b);
dwarfget1(&b);
files = (char*)b.p;
while(b.p!=nil && *b.p!=0){
dwarfgetstring(&b);
dwarfget128(&b);
dwarfget128(&b);
dwarfget128(&b);
}
dwarfget1(&b);
/* move on to the program */
if(b.p == nil || b.p > prog){
werrstr("bad header");
goto bad;
}
b.p = prog;
reset.addr = 0;
reset.file = 1;
reset.line = 1;
reset.column = 0;
reset.flags = isstmt ? Isstmt : 0;
reset.isa = 0;
cur = reset;
emit = reset;
nf = 0;
start = 0;
if(trace) werrstr("program @ %lu ... %.*H opbase = %d", b.p - d->line.data, b.ep-b.p, b.p, opcodebase);
first = 1;
while(b.p != nil){
firstline = 0;
op = dwarfget1(&b);
if(trace) werrstr("\tline %lu, addr 0x%x, op %d %.10H", cur.line, cur.addr, op, b.p);
if(op >= opcodebase){
a = (op - opcodebase) / linerange;
l = (op - opcodebase) % linerange + linebase;
cur.line += l;
cur.addr += a * quantum;
if(trace) werrstr(" +%d,%d", a, l);
emit:
if(first){
if(cur.addr > pc){
werrstr("found wrong line mapping 0x%x for pc 0x%x", cur.addr, pc);
/* This is an overzealous check. gcc can produce discontiguous ranges
and reorder statements, so it's possible for a future line to start
ahead of pc and still find a matching one. */
/*goto out;*/
firstline = 1;
}
first = 0;
start = cur.addr;
}
if(cur.addr > pc && !firstline)
break;
if(b.p == nil){
werrstr("buffer underflow in line mapping");
goto out;
}
emit = cur;
if(emit.flags & EndSequence){
werrstr("found wrong line mapping 0x%x-0x%x for pc 0x%x", start, cur.addr, pc);
goto out;
}
cur.flags &= ~(BasicDwarfBlock|PrologueEnd|EpilogueBegin);
}else{
switch(op){
case 0: /* extended op code */
if(trace) werrstr(" ext");
len = dwarfget128(&b);
end = b.p+len;
if(b.p == nil || end > b.ep || end < b.p || len < 1)
goto bad;
switch(dwarfget1(&b)){
case 1: /* end sequence */
if(trace) werrstr(" end");
cur.flags |= EndSequence;
goto emit;
case 2: /* set address */
cur.addr = dwarfgetaddr(&b);
if(trace) werrstr(" set pc 0x%x", cur.addr);
break;
case 3: /* define file */
newf = malloc(nf+1*sizeof(f[0]));
if (newf)
RtlMoveMemory(newf, f, nf*sizeof(f[0]));
if(newf == nil)
goto out;
free(f);
f = newf;
f[nf++] = s = dwarfgetstring(&b);
DPRINT1("str %s", s);
dwarfget128(&b);
dwarfget128(&b);
dwarfget128(&b);
if(trace) werrstr(" def file %s", s);
break;
}
if(b.p == nil || b.p > end)
goto bad;
b.p = end;
break;
case 1: /* emit */
if(trace) werrstr(" emit");
goto emit;
case 2: /* advance pc */
a = dwarfget128(&b);
if(trace) werrstr(" advance pc + %lu", a*quantum);
cur.addr += a * quantum;
break;
case 3: /* advance line */
l = dwarfget128s(&b);
if(trace) werrstr(" advance line + %ld", l);
cur.line += l;
break;
case 4: /* set file */
if(trace) werrstr(" set file");
cur.file = dwarfget128s(&b);
break;
case 5: /* set column */
if(trace) werrstr(" set column");
cur.column = dwarfget128(&b);
break;
case 6: /* negate stmt */
if(trace) werrstr(" negate stmt");
cur.flags ^= Isstmt;
break;
case 7: /* set basic block */
if(trace) werrstr(" set basic block");
cur.flags |= BasicDwarfBlock;
break;
case 8: /* const add pc */
a = (255 - opcodebase) / linerange * quantum;
if(trace) werrstr(" const add pc + %d", a);
cur.addr += a;
break;
case 9: /* fixed advance pc */
a = dwarfget2(&b);
if(trace) werrstr(" fixed advance pc + %d", a);
cur.addr += a;
break;
case 10: /* set prologue end */
if(trace) werrstr(" set prologue end");
cur.flags |= PrologueEnd;
break;
case 11: /* set epilogue begin */
if(trace) werrstr(" set epilogue begin");
cur.flags |= EpilogueBegin;
break;
case 12: /* set isa */
if(trace) werrstr(" set isa");
cur.isa = dwarfget128(&b);
break;
default: /* something new - skip it */
if(trace) werrstr(" unknown %d", opcount[op]);
for(i=0; i<opcount[op]; i++)
dwarfget128(&b);
break;
}
}
}
if(b.p == nil)
goto bad;
/* finally! the data we seek is in "emit" */
if(emit.file == 0){
werrstr("invalid file index in mapping data");
goto out;
}
if(line)
*line = emit.line;
/* skip over first emit.file-2 guys */
b.p = (uchar*)files;
for(i=emit.file-1; i > 0 && b.p!=nil && *b.p!=0; i--){
dwarfgetstring(&b);
dwarfget128(&b);
dwarfget128(&b);
dwarfget128(&b);
}
if(b.p == nil){
werrstr("problem parsing file data second time (cannot happen)");
goto bad;
}
if(*b.p == 0){
if(i >= nf){
werrstr("bad file index in mapping data");
goto bad;
}
b.p = (uchar*)f[i];
}
s = dwarfgetstring(&b);
*file = s;
i = dwarfget128(&b); /* directory */
x = dwarfget128(&b);
x = dwarfget128(&b);
/* fetch dir name */
cdir = sym.attrs.have.compdir ? sym.attrs.compdir : 0;
char *dwarfdir;
dwarfdir = nil;
b.p = dirs;
for (x = 1; b.p && *b.p; x++) {
dwarfdir = dwarfgetstring(&b);
if (x == i) break;
}
if (!cdir && dwarfdir)
cdir = dwarfdir;
char *filefull = malloc(strlen(cdir) + strlen(*file) + 2);
strcpy(filefull, cdir);
strcat(filefull, "/");
strcat(filefull, *file);
*file = filefull;
*function = nil;
lastline = 0;
runit = dwarfaddrtounit(d, pc, &unit);
if (runit == 0) {
DwarfSym compunit = { };
int renum = dwarfenumunit(d, unit, &compunit);
if (renum < 0)
return -1;
renum = dwarfnextsymat(d, &compunit, proc);
while (renum == 0) {
if (proc->attrs.tag == TagSubprogram &&
proc->attrs.have.name)
{
if (proc->attrs.lowpc <= pc && proc->attrs.highpc > pc) {
*function = malloc(strlen(proc->attrs.name)+1);
strcpy(*function, proc->attrs.name);
goto done;
}
}
renum = dwarfnextsym(d, proc);
}
}
// Next search by declaration
runit = dwarfaddrtounit(d, pc, &unit);
if (runit == 0) {
DwarfSym compunit = { };
int renum = dwarfenumunit(d, unit, &compunit);
if (renum < 0)
return -1;
renum = dwarfnextsymat(d, &compunit, proc);
while (renum == 0) {
if (proc->attrs.tag == TagSubprogram &&
proc->attrs.have.name &&
proc->attrs.declfile == emit.file)
{
if (proc->attrs.declline <= *line &&
proc->attrs.declline > lastline) {
free(*function);
*function = malloc(strlen(proc->attrs.name)+1);
strcpy(*function, proc->attrs.name);
goto done;
}
lastline = proc->attrs.declline;
}
renum = dwarfnextsym(d, proc);
}
}
/* free at last, free at last */
done:
free(f);
return 0;
bad:
werrstr("corrupted line mapping for 0x%x", pc);
out:
free(f);
return -1;
}
static int
dexec(DwarfBuf *b, State *s, int locstop)
{
int c;
long arg1, arg2;
DwarfExpr *e;
for(;;){
if(b->p == b->ep){
if(s->initr)
s->loc = s->endloc;
return 0;
}
c = dwarfget1(b);
if(b->p == nil){
werrstr("ran out of instructions during cfa program");
if(trace) werrstr("%r\n");
return -1;
}
if(trace) werrstr("+ loc=0x%lux op 0x%ux ", s->loc, c);
switch(c>>6){
case 1: /* advance location */
arg1 = c&0x3F;
advance:
if(trace) werrstr("loc += %ld\n", arg1*s->iquantum);
s->loc += arg1 * s->iquantum;
if(locstop)
return 0;
continue;
case 2: /* offset rule */
arg1 = c&0x3F;
arg2 = dwarfget128(b);
offset:
if(trace) werrstr("r%ld += %ld\n", arg1, arg2*s->dquantum);
if(checkreg(s, arg1) < 0)
return -1;
s->r[arg1].type = RuleCfaOffset;
s->r[arg1].offset = arg2 * s->dquantum;
continue;
case 3: /* restore initial setting */
arg1 = c&0x3F;
restore:
if(trace) werrstr("r%ld = init\n", arg1);
if(checkreg(s, arg1) < 0)
return -1;
s->r[arg1] = s->initr[arg1];
continue;
}
switch(c){
case 0: /* nop */
if(trace) werrstr("nop\n");
continue;
case 0x01: /* set location */
s->loc = dwarfgetaddr(b);
if(trace) werrstr("loc = 0x%lux\n", s->loc);
if(locstop)
return 0;
continue;
case 0x02: /* advance loc1 */
arg1 = dwarfget1(b);
goto advance;
case 0x03: /* advance loc2 */
arg1 = dwarfget2(b);
goto advance;
case 0x04: /* advance loc4 */
arg1 = dwarfget4(b);
goto advance;
case 0x05: /* offset extended */
arg1 = dwarfget128(b);
arg2 = dwarfget128(b);
goto offset;
case 0x06: /* restore extended */
arg1 = dwarfget128(b);
goto restore;
case 0x07: /* undefined */
arg1 = dwarfget128(b);
if(trace) werrstr("r%ld = undef\n", arg1);
if(checkreg(s, arg1) < 0)
return -1;
s->r[arg1].type = RuleUndef;
continue;
case 0x08: /* same value */
arg1 = dwarfget128(b);
if(trace) werrstr("r%ld = same\n", arg1);
if(checkreg(s, arg1) < 0)
return -1;
s->r[arg1].type = RuleSame;
continue;
case 0x09: /* register */
arg1 = dwarfget128(b);
arg2 = dwarfget128(b);
if(trace) werrstr("r%ld = r%ld\n", arg1, arg2);
if(checkreg(s, arg1) < 0 || checkreg(s, arg2) < 0)
return -1;
s->r[arg1].type = RuleRegister;
s->r[arg1].reg = arg2;
continue;
case 0x0A: /* remember state */
e = malloc(s->nr*sizeof(e[0]));
if(trace) werrstr("push\n");
if(e == nil)
return -1;
void *newstack = malloc(s->nstack*sizeof(s->stack[0]));
RtlMoveMemory(newstack, s->stack, s->nstack*sizeof(s->stack[0]));
if (newstack) {
free(s->stack);
s->stack = newstack;
} else {
free(e);
return -1;
}
if(b->p == nil){
free(e);
return -1;
}
s->stack[s->nstack++] = e;
memmove(e, s->r, s->nr*sizeof(e[0]));
continue;
case 0x0B: /* restore state */
if(trace) werrstr("pop\n");
if(s->nstack == 0){
werrstr("restore state underflow");
return -1;
}
e = s->stack[s->nstack-1];
memmove(s->r, e, s->nr*sizeof(e[0]));
free(e);
s->nstack--;
continue;
case 0x0C: /* def cfa */
arg1 = dwarfget128(b);
arg2 = dwarfget128(b);
defcfa:
if(trace) werrstr("cfa %ld(r%ld)\n", arg2, arg1);
if(checkreg(s, arg1) < 0)
return -1;
s->cfa->type = RuleRegOff;
s->cfa->reg = arg1;
s->cfa->offset = arg2;
continue;
case 0x0D: /* def cfa register */
arg1 = dwarfget128(b);
if(trace) werrstr("cfa reg r%ld\n", arg1);
if(s->cfa->type != RuleRegOff){
werrstr("change CFA register but CFA not in register+offset form");
return -1;
}
if(checkreg(s, arg1) < 0)
return -1;
s->cfa->reg = arg1;
continue;
case 0x0E: /* def cfa offset */
arg1 = dwarfget128(b);
cfaoffset:
if(trace) werrstr("cfa off %ld\n", arg1);
if(s->cfa->type != RuleRegOff){
werrstr("change CFA offset but CFA not in register+offset form");
return -1;
}
s->cfa->offset = arg1;
continue;
case 0x0F: /* def cfa expression */
if(trace) werrstr("cfa expr\n");
s->cfa->type = RuleLocation;
s->cfa->loc.len = dwarfget128(b);
s->cfa->loc.data = dwarfgetnref(b, s->cfa->loc.len);
continue;
case 0x10: /* def reg expression */
arg1 = dwarfget128(b);
if(trace) werrstr("reg expr r%ld\n", arg1);
if(checkreg(s, arg1) < 0)
return -1;
s->r[arg1].type = RuleLocation;
s->r[arg1].loc.len = dwarfget128(b);
s->r[arg1].loc.data = dwarfgetnref(b, s->r[arg1].loc.len);
continue;
case 0x11: /* offset extended */
arg1 = dwarfget128(b);
arg2 = dwarfget128s(b);
goto offset;
case 0x12: /* cfa sf */
arg1 = dwarfget128(b);
arg2 = dwarfget128s(b);
goto defcfa;
case 0x13: /* cfa offset sf */
arg1 = dwarfget128s(b);
goto cfaoffset;
default: /* unknown */
werrstr("unknown opcode 0x%ux in cfa program", c);
return -1;
}
}
/* not reached */
}
int
dwarfpctoline(Dwarf *d, ulong pc, char **cdir, char **dir, char **file, ulong *line, ulong *mtime, ulong *length)
{
uchar *prog, *opcount, *end;
ulong off, unit, len, vers, x, start;
int i, first, op, a, l, quantum, isstmt, linebase, linerange, opcodebase, nf;
char *files, *dirs, *s;
DwarfBuf b;
DwarfSym sym;
State emit, cur, reset;
uchar **f, **newf;
f = nil;
if(dwarfaddrtounit(d, pc, &unit) < 0
|| dwarflookuptag(d, unit, TagCompileUnit, &sym) < 0)
return -1;
if(!sym.attrs.have.stmtlist){
werrstr("no line mapping information for 0x%lux", pc);
return -1;
}
off = sym.attrs.stmtlist;
if(off >= d->line.len){
fprint(2, "bad stmtlist\n");
goto bad;
}
if(trace) fprint(2, "unit 0x%lux stmtlist 0x%lux\n", unit, sym.attrs.stmtlist);
memset(&b, 0, sizeof b);
b.d = d;
b.p = d->line.data + off;
b.ep = b.p + d->line.len;
b.addrsize = sym.b.addrsize; /* should i get this from somewhere else? */
len = dwarfget4(&b);
if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){
fprint(2, "bad len\n");
goto bad;
}
b.ep = b.p+len;
vers = dwarfget2(&b);
if(vers != 2){
werrstr("bad dwarf version 0x%lux", vers);
return -1;
}
len = dwarfget4(&b);
if(b.p==nil || b.p+len > b.ep || b.p+len < b.p){
fprint(2, "another bad len\n");
goto bad;
}
prog = b.p+len;
quantum = dwarfget1(&b);
isstmt = dwarfget1(&b);
linebase = (schar)dwarfget1(&b);
linerange = (schar)dwarfget1(&b);
opcodebase = dwarfget1(&b);
opcount = b.p-1;
dwarfgetnref(&b, opcodebase-1);
if(b.p == nil){
fprint(2, "bad opcode chart\n");
goto bad;
}
/* just skip the files and dirs for now; we'll come back */
dirs = (char*)b.p;
while(b.p!=nil && *b.p!=0)
dwarfgetstring(&b);
dwarfget1(&b);
files = (char*)b.p;
while(b.p!=nil && *b.p!=0){
dwarfgetstring(&b);
dwarfget128(&b);
dwarfget128(&b);
dwarfget128(&b);
}
dwarfget1(&b);
/* move on to the program */
if(b.p == nil || b.p > prog){
fprint(2, "bad header\n");
goto bad;
}
b.p = prog;
reset.addr = 0;
reset.file = 1;
reset.line = 1;
reset.column = 0;
reset.flags = isstmt ? Isstmt : 0;
reset.isa = 0;
cur = reset;
emit = reset;
nf = 0;
start = 0;
if(trace) fprint(2, "program @ %lud ... %.*H opbase = %d\n", b.p - d->line.data, b.ep-b.p, b.p, opcodebase);
first = 1;
while(b.p != nil){
op = dwarfget1(&b);
if(trace) fprint(2, "\tline %lud, addr 0x%lux, op %d %.10H", cur.line, cur.addr, op, b.p);
if(op >= opcodebase){
a = (op - opcodebase) / linerange;
l = (op - opcodebase) % linerange + linebase;
cur.line += l;
cur.addr += a * quantum;
if(trace) fprint(2, " +%d,%d\n", a, l);
emit:
if(first){
if(cur.addr > pc){
werrstr("found wrong line mapping 0x%lux for pc 0x%lux", cur.addr, pc);
goto out;
}
first = 0;
start = cur.addr;
}
if(cur.addr > pc)
break;
if(b.p == nil){
werrstr("buffer underflow in line mapping");
goto out;
}
emit = cur;
if(emit.flags & EndSequence){
werrstr("found wrong line mapping 0x%lux-0x%lux for pc 0x%lux", start, cur.addr, pc);
goto out;
}
cur.flags &= ~(BasicDwarfBlock|PrologueEnd|EpilogueBegin);
}else{
switch(op){
case 0: /* extended op code */
if(trace) fprint(2, " ext");
len = dwarfget128(&b);
end = b.p+len;
if(b.p == nil || end > b.ep || end < b.p || len < 1)
goto bad;
switch(dwarfget1(&b)){
case 1: /* end sequence */
if(trace) fprint(2, " end\n");
cur.flags |= EndSequence;
goto emit;
case 2: /* set address */
cur.addr = dwarfgetaddr(&b);
if(trace) fprint(2, " set pc 0x%lux\n", cur.addr);
break;
case 3: /* define file */
newf = realloc(f, (nf+1)*sizeof(f[0]));
if(newf == nil)
goto out;
f = newf;
f[nf++] = b.p;
s = dwarfgetstring(&b);
dwarfget128(&b);
dwarfget128(&b);
dwarfget128(&b);
if(trace) fprint(2, " def file %s\n", s);
break;
}
if(b.p == nil || b.p > end)
goto bad;
b.p = end;
break;
case 1: /* emit */
if(trace) fprint(2, " emit\n");
goto emit;
case 2: /* advance pc */
a = dwarfget128(&b);
if(trace) fprint(2, " advance pc + %lud\n", a*quantum);
cur.addr += a * quantum;
break;
case 3: /* advance line */
l = dwarfget128s(&b);
if(trace) fprint(2, " advance line + %ld\n", l);
cur.line += l;
break;
case 4: /* set file */
if(trace) fprint(2, " set file\n");
cur.file = dwarfget128s(&b);
break;
case 5: /* set column */
if(trace) fprint(2, " set column\n");
cur.column = dwarfget128(&b);
break;
case 6: /* negate stmt */
if(trace) fprint(2, " negate stmt\n");
cur.flags ^= Isstmt;
break;
case 7: /* set basic block */
if(trace) fprint(2, " set basic block\n");
cur.flags |= BasicDwarfBlock;
break;
case 8: /* const add pc */
a = (255 - opcodebase) / linerange * quantum;
if(trace) fprint(2, " const add pc + %d\n", a);
cur.addr += a;
break;
case 9: /* fixed advance pc */
a = dwarfget2(&b);
if(trace) fprint(2, " fixed advance pc + %d\n", a);
cur.addr += a;
break;
case 10: /* set prologue end */
if(trace) fprint(2, " set prologue end\n");
cur.flags |= PrologueEnd;
break;
case 11: /* set epilogue begin */
if(trace) fprint(2, " set epilogue begin\n");
cur.flags |= EpilogueBegin;
break;
case 12: /* set isa */
if(trace) fprint(2, " set isa\n");
cur.isa = dwarfget128(&b);
break;
default: /* something new - skip it */
if(trace) fprint(2, " unknown %d\n", opcount[op]);
for(i=0; i<opcount[op]; i++)
dwarfget128(&b);
break;
}
}
}
if(b.p == nil)
goto bad;
/* finally! the data we seek is in "emit" */
if(emit.file == 0){
werrstr("invalid file index in mapping data");
goto out;
}
if(line)
*line = emit.line;
/* skip over first emit.file-2 guys */
b.p = (uchar*)files;
for(i=emit.file-1; i > 0 && b.p!=nil && *b.p!=0; i--){
dwarfgetstring(&b);
dwarfget128(&b);
dwarfget128(&b);
dwarfget128(&b);
}
if(b.p == nil){
werrstr("problem parsing file data second time (cannot happen)");
goto bad;
}
if(*b.p == 0){
if(i >= nf){
werrstr("bad file index in mapping data");
goto bad;
}
b.p = f[i];
}
s = dwarfgetstring(&b);
if(file)
*file = s;
i = dwarfget128(&b); /* directory */
x = dwarfget128(&b);
if(mtime)
*mtime = x;
x = dwarfget128(&b);
if(length)
*length = x;
/* fetch dir name */
if(cdir)
*cdir = sym.attrs.compdir;
if(dir){
if(i == 0)
*dir = nil;
else{
b.p = (uchar*)dirs;
for(i--; i>0 && b.p!=nil && *b.p!=0; i--)
dwarfgetstring(&b);
if(b.p==nil || *b.p==0){
werrstr("bad directory reference in line mapping");
goto out; /* can only happen with bad dir index */
}
*dir = dwarfgetstring(&b);
}
}
/* free at last, free at last */
free(f);
return 0;
bad:
werrstr("corrupted line mapping for 0x%lux", pc);
out:
free(f);
return -1;
}