/*
* Entry point called by the trace wrap functions in erl_bif_wrap.c
*
* The trace wrap functions are themselves called through the export
* entries instead of the original BIF functions.
*/
Eterm
erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
{
Eterm result;
Eterm (*func)(Process*, Eterm*, BeamInstr*);
Export* ep = bif_export[bif_index];
Uint32 flags = 0, flags_meta = 0;
ErtsTracer meta_tracer = erts_tracer_nil;
int applying = (I == &(ep->code[3])); /* Yup, the apply code for a bif
* is actually in the
* export entry */
BeamInstr *cp = p->cp;
GenericBp* g;
GenericBpData* bp = NULL;
Uint bp_flags = 0;
ERTS_SMP_CHK_HAVE_ONLY_MAIN_PROC_LOCK(p);
g = (GenericBp *) ep->fake_op_func_info_for_hipe[1];
if (g) {
bp = &g->data[erts_active_bp_ix()];
bp_flags = bp->flags;
}
/*
* Make continuation pointer OK, it is not during direct BIF calls,
* but it is correct during apply of bif.
*/
if (!applying) {
p->cp = I;
}
if (bp_flags & (ERTS_BPF_LOCAL_TRACE|ERTS_BPF_GLOBAL_TRACE) &&
IS_TRACED_FL(p, F_TRACE_CALLS)) {
int local = !!(bp_flags & ERTS_BPF_LOCAL_TRACE);
flags = erts_call_trace(p, ep->code, bp->local_ms, args,
local, &ERTS_TRACER(p));
}
if (bp_flags & ERTS_BPF_META_TRACE) {
ErtsTracer old_tracer;
meta_tracer = erts_smp_atomic_read_nob(&bp->meta_tracer->tracer);
old_tracer = meta_tracer;
flags_meta = erts_call_trace(p, ep->code, bp->meta_ms, args,
0, &meta_tracer);
if (!ERTS_TRACER_COMPARE(old_tracer, meta_tracer)) {
ErtsTracer new_tracer = erts_tracer_nil;
erts_tracer_update(&new_tracer, meta_tracer);
if (old_tracer == erts_smp_atomic_cmpxchg_acqb(
&bp->meta_tracer->tracer,
(erts_aint_t)new_tracer,
(erts_aint_t)old_tracer)) {
ERTS_TRACER_CLEAR(&old_tracer);
} else {
ERTS_TRACER_CLEAR(&new_tracer);
}
}
}
if (bp_flags & ERTS_BPF_TIME_TRACE_ACTIVE &&
IS_TRACED_FL(p, F_TRACE_CALLS)) {
BeamInstr *pc = (BeamInstr *)ep->code+3;
erts_trace_time_call(p, pc, bp->time);
}
/* Restore original continuation pointer (if changed). */
p->cp = cp;
func = bif_table[bif_index].f;
result = func(p, args, I);
if (applying && (flags & MATCH_SET_RETURN_TO_TRACE)) {
BeamInstr i_return_trace = beam_return_trace[0];
BeamInstr i_return_to_trace = beam_return_to_trace[0];
BeamInstr i_return_time_trace = beam_return_time_trace[0];
Eterm *cpp;
/* Maybe advance cp to skip trace stack frames */
for (cpp = p->stop; ; cp = cp_val(*cpp++)) {
if (*cp == i_return_trace) {
/* Skip stack frame variables */
while (is_not_CP(*cpp)) cpp++;
cpp += 2; /* Skip return_trace parameters */
} else if (*cp == i_return_time_trace) {
/* Skip stack frame variables */
while (is_not_CP(*cpp)) cpp++;
cpp += 1; /* Skip return_time_trace parameters */
} else if (*cp == i_return_to_trace) {
/* A return_to trace message is going to be generated
* by normal means, so we do not have to.
*/
cp = NULL;
break;
} else break;
}
}
/* Try to get these in the order
* they usually appear in normal code... */
if (is_non_value(result)) {
Uint reason = p->freason;
if (reason != TRAP) {
Eterm class;
Eterm value = p->fvalue;
/* Expand error value like in handle_error() */
if (reason & EXF_ARGLIST) {
Eterm *tp;
ASSERT(is_tuple(value));
tp = tuple_val(value);
value = tp[1];
}
if ((reason & EXF_THROWN) && (p->catches <= 0)) {
Eterm *hp = HAlloc(p, 3);
value = TUPLE2(hp, am_nocatch, value);
reason = EXC_ERROR;
}
/* Note: expand_error_value() could theoretically
* allocate on the heap, but not for any error
* returned by a BIF, and it would do no harm,
* just be annoying.
*/
value = expand_error_value(p, reason, value);
class = exception_tag[GET_EXC_CLASS(reason)];
if (flags_meta & MATCH_SET_EXCEPTION_TRACE) {
erts_trace_exception(p, ep->code, class, value,
&meta_tracer);
}
if (flags & MATCH_SET_EXCEPTION_TRACE) {
erts_trace_exception(p, ep->code, class, value,
&ERTS_TRACER(p));
}
Eterm
erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
Export* ep, BeamInstr *cp, Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer)
{
if (applying && (flags & MATCH_SET_RETURN_TO_TRACE)) {
BeamInstr i_return_trace = beam_return_trace[0];
BeamInstr i_return_to_trace = beam_return_to_trace[0];
BeamInstr i_return_time_trace = beam_return_time_trace[0];
Eterm *cpp;
/* Maybe advance cp to skip trace stack frames */
for (cpp = p->stop; ; cp = cp_val(*cpp++)) {
if (*cp == i_return_trace) {
/* Skip stack frame variables */
while (is_not_CP(*cpp)) cpp++;
cpp += 2; /* Skip return_trace parameters */
} else if (*cp == i_return_time_trace) {
/* Skip stack frame variables */
while (is_not_CP(*cpp)) cpp++;
cpp += 1; /* Skip return_time_trace parameters */
} else if (*cp == i_return_to_trace) {
/* A return_to trace message is going to be generated
* by normal means, so we do not have to.
*/
cp = NULL;
break;
} else break;
}
}
/* Try to get these in the order
* they usually appear in normal code... */
if (is_non_value(result)) {
Uint reason = p->freason;
if (reason != TRAP) {
Eterm class;
Eterm value = p->fvalue;
/* Expand error value like in handle_error() */
if (reason & EXF_ARGLIST) {
Eterm *tp;
ASSERT(is_tuple(value));
tp = tuple_val(value);
value = tp[1];
}
if ((reason & EXF_THROWN) && (p->catches <= 0)) {
Eterm *hp = HAlloc(p, 3);
value = TUPLE2(hp, am_nocatch, value);
reason = EXC_ERROR;
}
/* Note: expand_error_value() could theoretically
* allocate on the heap, but not for any error
* returned by a BIF, and it would do no harm,
* just be annoying.
*/
value = expand_error_value(p, reason, value);
class = exception_tag[GET_EXC_CLASS(reason)];
if (flags_meta & MATCH_SET_EXCEPTION_TRACE) {
erts_trace_exception(p, &ep->info.mfa, class, value,
&meta_tracer);
}
if (flags & MATCH_SET_EXCEPTION_TRACE) {
erts_trace_exception(p, &ep->info.mfa, class, value,
&ERTS_TRACER(p));
}