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-rw-r--r--erts/emulator/beam/beam_bif_load.c7
-rw-r--r--erts/emulator/beam/beam_bp.c126
-rw-r--r--erts/emulator/beam/beam_emu.c294
-rw-r--r--erts/emulator/beam/bif.c7
-rw-r--r--erts/emulator/beam/bif_instrs.tab17
-rw-r--r--erts/emulator/beam/erl_bif_info.c12
-rw-r--r--erts/emulator/beam/erl_db_util.c13
-rw-r--r--erts/emulator/beam/erl_gc.c17
-rw-r--r--erts/emulator/beam/erl_nfunc_sched.c6
-rw-r--r--erts/emulator/beam/erl_nfunc_sched.h13
-rw-r--r--erts/emulator/beam/erl_nif.c7
-rw-r--r--erts/emulator/beam/erl_process.c15
-rw-r--r--erts/emulator/beam/erl_process.h1
-rw-r--r--erts/emulator/beam/erl_trace.h2
-rw-r--r--erts/emulator/beam/instrs.tab51
-rw-r--r--erts/emulator/beam/macros.tab46
-rw-r--r--erts/emulator/beam/trace_instrs.tab19
-rw-r--r--erts/emulator/hipe/hipe_debug.c1
-rw-r--r--erts/emulator/hipe/hipe_instrs.tab4
-rw-r--r--erts/emulator/hipe/hipe_mode_switch.c8
-rw-r--r--erts/emulator/test/bif_SUITE.erl15
-rw-r--r--erts/emulator/test/hibernate_SUITE.erl9
22 files changed, 339 insertions, 351 deletions
diff --git a/erts/emulator/beam/beam_bif_load.c b/erts/emulator/beam/beam_bif_load.c
index 4c8ee5178a..04b2ed64b7 100644
--- a/erts/emulator/beam/beam_bif_load.c
+++ b/erts/emulator/beam/beam_bif_load.c
@@ -1125,13 +1125,12 @@ check_process_code(Process* rp, Module* modp, int *redsp, int fcalls)
mod_size = modp->old.code_length;
/*
- * Check if current instruction or continuation pointer points into module.
+ * Check if the instruction pointer points into module.
*/
- if (ErtsInArea(rp->i, mod_start, mod_size)
- || ErtsInArea(rp->cp, mod_start, mod_size)) {
+ if (ErtsInArea(rp->i, mod_start, mod_size)) {
return am_true;
}
-
+
*redsp += 1;
if (erts_check_nif_export_in_area(rp, mod_start, mod_size))
diff --git a/erts/emulator/beam/beam_bp.c b/erts/emulator/beam/beam_bp.c
index 0832b3f374..10940072ae 100644
--- a/erts/emulator/beam/beam_bp.c
+++ b/erts/emulator/beam/beam_bp.c
@@ -642,46 +642,35 @@ erts_clear_export_break(Module* modp, ErtsCodeInfo *ci)
}
/*
- * If c_p->cp is a trace return instruction, we set cp
- * to be the place where we again start to execute code.
+ * If the topmost continuation pointer on the stack is a trace return
+ * instruction, we modify it to be the place where we again start to
+ * execute code.
*
- * cp is used by match spec {caller} to get the calling
- * function, and if we don't do this fixup it will be
- * 'undefined'. This has the odd side effect of {caller}
- * not really being which function is the caller, but
- * rather which function we are about to return to.
+ * This continuation pointer is used by match spec {caller} to get the
+ * calling function, and if we don't do this fixup it will be
+ * 'undefined'. This has the odd side effect of {caller} not really
+ * being the function which is the caller, but rather the function
+ * which we are about to return to.
*/
static void fixup_cp_before_trace(Process *c_p, int *return_to_trace)
{
- Eterm *cpp, *E = c_p->stop;
- BeamInstr w = *c_p->cp;
- if (BeamIsOpCode(w, op_return_trace)) {
- cpp = &E[2];
- } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
- *return_to_trace = 1;
- cpp = &E[0];
- } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
- cpp = &E[0];
- } else {
- cpp = NULL;
- }
- if (cpp) {
- for (;;) {
- BeamInstr w = *cp_val(*cpp);
- if (BeamIsOpCode(w, op_return_trace)) {
- cpp += 3;
- } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
- *return_to_trace = 1;
- cpp += 1;
- } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
- cpp += 2;
- } else {
- break;
- }
+ Eterm *cpp = c_p->stop;
+
+ for (;;) {
+ BeamInstr w = *cp_val(*cpp);
+ if (BeamIsOpCode(w, op_return_trace)) {
+ cpp += 3;
+ } else if (BeamIsOpCode(w, op_i_return_to_trace)) {
+ *return_to_trace = 1;
+ cpp += 1;
+ } else if (BeamIsOpCode(w, op_i_return_time_trace)) {
+ cpp += 2;
+ } else {
+ break;
}
- c_p->cp = (BeamInstr *) cp_val(*cpp);
- ASSERT(is_CP(*cpp));
}
+ c_p->stop[0] = (Eterm) cp_val(*cpp);
+ ASSERT(is_CP(*cpp));
}
BeamInstr
@@ -743,12 +732,13 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
if (bp_flags & ERTS_BPF_TIME_TRACE_ACTIVE) {
Eterm w;
+ Eterm* E;
erts_trace_time_call(c_p, info, bp->time);
- w = (BeamInstr) *c_p->cp;
+ E = c_p->stop;
+ w = (BeamInstr) E[0];
if (! (BeamIsOpCode(w, op_i_return_time_trace) ||
BeamIsOpCode(w, op_return_trace) ||
BeamIsOpCode(w, op_i_return_to_trace)) ) {
- Eterm* E = c_p->stop;
ASSERT(c_p->htop <= E && E <= c_p->hend);
if (E - 2 < c_p->htop) {
(void) erts_garbage_collect(c_p, 2, reg, info->mfa.arity);
@@ -759,9 +749,8 @@ erts_generic_breakpoint(Process* c_p, ErtsCodeInfo *info, Eterm* reg)
ASSERT(c_p->htop <= E && E <= c_p->hend);
E -= 2;
- E[0] = make_cp(erts_codeinfo_to_code(info));
- E[1] = make_cp(c_p->cp); /* original return address */
- c_p->cp = beam_return_time_trace;
+ E[1] = make_cp(erts_codeinfo_to_code(info));
+ E[0] = (Eterm) beam_return_time_trace;
c_p->stop = E;
}
}
@@ -790,7 +779,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
int applying = (I == ep->beam); /* Yup, the apply code for a bif
* is actually in the
* export entry */
- BeamInstr *cp = p->cp;
+ BeamInstr* cp = (BeamInstr *) p->stop[0];
GenericBp* g;
GenericBpData* bp = NULL;
Uint bp_flags = 0;
@@ -809,7 +798,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
* but it is correct during apply of bif.
*/
if (!applying) {
- p->cp = I;
+ p->stop[0] = (Eterm) I;
} else {
fixup_cp_before_trace(p, &return_to_trace);
}
@@ -846,7 +835,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
}
/* Restore original continuation pointer (if changed). */
- p->cp = cp;
+ p->stop[0] = (Eterm) cp;
func = bif_table[bif_index].f;
@@ -854,7 +843,7 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
if (erts_nif_export_check_save_trace(p, result,
applying, ep,
- cp, flags,
+ flags,
flags_meta, I,
meta_tracer)) {
/*
@@ -865,24 +854,31 @@ erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr* I)
return result;
}
- return erts_bif_trace_epilogue(p, result, applying, ep, cp,
+ return erts_bif_trace_epilogue(p, result, applying, ep,
flags, flags_meta, I,
meta_tracer);
}
Eterm
erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
- Export* ep, BeamInstr *cp, Uint32 flags,
+ Export* ep, Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer)
{
+ BeamInstr *cp = NULL;
+
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++)) {
+ cpp = p->stop;
+ while (is_not_CP(*cpp)) {
+ cpp++;
+ }
+ for (cp = cp_val(*cpp++); ;) {
if (*cp == i_return_trace) {
/* Skip stack frame variables */
while (is_not_CP(*cpp)) cpp++;
@@ -897,8 +893,11 @@ erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
*/
cp = NULL;
break;
- } else break;
- }
+ } else {
+ break;
+ }
+ cp = cp_val(*cpp++);
+ }
}
/* Try to get these in the order
@@ -939,7 +938,7 @@ erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
if ((flags & MATCH_SET_RETURN_TO_TRACE) && p->catches > 0) {
/* can only happen if(local)*/
Eterm *ptr = p->stop;
- ASSERT(is_CP(*ptr));
+ ASSERT(!applying || is_CP(*ptr));
ASSERT(ptr <= STACK_START(p));
/* Search the nearest stack frame for a catch */
while (++ptr < STACK_START(p)) {
@@ -991,19 +990,19 @@ do_call_trace(Process* c_p, ErtsCodeInfo* info, Eterm* reg,
int local, Binary* ms, ErtsTracer tracer)
{
int return_to_trace = 0;
- BeamInstr *cp_save = c_p->cp;
Uint32 flags;
Uint need = 0;
+ Eterm cp_save;
Eterm* E = c_p->stop;
- fixup_cp_before_trace(c_p, &return_to_trace);
+ cp_save = E[0];
+ fixup_cp_before_trace(c_p, &return_to_trace);
ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
flags = erts_call_trace(c_p, info, ms, reg, local, &tracer);
ERTS_REQ_PROC_MAIN_LOCK(c_p);
- /* restore cp after potential fixup */
- c_p->cp = cp_save;
+ E[0] = cp_save;
ASSERT(!ERTS_PROC_IS_EXITING(c_p));
if ((flags & MATCH_SET_RETURN_TO_TRACE) && !return_to_trace) {
@@ -1023,28 +1022,23 @@ do_call_trace(Process* c_p, ErtsCodeInfo* info, Eterm* reg,
if (flags & MATCH_SET_RETURN_TO_TRACE && !return_to_trace) {
E -= 1;
ASSERT(c_p->htop <= E && E <= c_p->hend);
- E[0] = make_cp(c_p->cp);
- c_p->cp = beam_return_to_trace;
+ E[0] = (Eterm) beam_return_to_trace;
+ c_p->stop = E;
}
- if (flags & MATCH_SET_RX_TRACE)
- {
+ if (flags & MATCH_SET_RX_TRACE) {
E -= 3;
c_p->stop = E;
ASSERT(c_p->htop <= E && E <= c_p->hend);
ASSERT(is_CP((Eterm) (UWord) (&info->mfa.module)));
ASSERT(IS_TRACER_VALID(tracer));
- E[2] = make_cp(c_p->cp);
- E[1] = copy_object(tracer, c_p);
- E[0] = make_cp(&info->mfa.module);
- /* We ARE at the beginning of an instruction,
- the funcinfo is above i. */
- c_p->cp = (flags & MATCH_SET_EXCEPTION_TRACE) ?
- beam_exception_trace : beam_return_trace;
+ E[2] = copy_object(tracer, c_p);
+ E[1] = make_cp(&info->mfa.module);
+ E[0] = (Eterm) ((flags & MATCH_SET_EXCEPTION_TRACE) ?
+ beam_exception_trace : beam_return_trace);
erts_proc_lock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
ERTS_TRACE_FLAGS(c_p) |= F_EXCEPTION_TRACE;
erts_proc_unlock(c_p, ERTS_PROC_LOCKS_ALL_MINOR);
- } else
- c_p->stop = E;
+ }
return tracer;
}
diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index 07c16e3415..9f8b56a5d5 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -141,10 +141,6 @@ do { \
BeamCodeAddr(IP) < (BeamInstr)LabelAddr(end_emulator_loop))
#endif /* NO_JUMP_TABLE */
-#define SET_CP(p, ip) \
- ASSERT(VALID_INSTR(*(ip))); \
- (p)->cp = (ip)
-
#define SET_I(ip) \
ASSERT(VALID_INSTR(* (Eterm *)(ip))); \
I = (ip)
@@ -524,7 +520,7 @@ init_emulator(void)
#define DTRACE_RETURN_FROM_PC(p) \
do { \
ErtsCodeMFA* cmfa; \
- if (DTRACE_ENABLED(function_return) && (cmfa = find_function_from_pc((p)->cp))) { \
+ if (DTRACE_ENABLED(function_return) && (cmfa = find_function_from_pc(cp_val((p)->stop[0])))) { \
DTRACE_RETURN((p), cmfa); \
} \
} while(0)
@@ -1443,7 +1439,7 @@ handle_error(Process* c_p, BeamInstr* pc, Eterm* reg, ErtsCodeMFA *bif_mfa)
reg[2] = Value;
reg[3] = c_p->ftrace;
if ((new_pc = next_catch(c_p, reg))) {
- c_p->cp = 0; /* To avoid keeping stale references. */
+ c_p->stop[0] = NIL; /* To avoid keeping stale references. */
ERTS_RECV_MARK_CLEAR(c_p); /* No longer safe to use this position */
return new_pc;
}
@@ -1481,35 +1477,6 @@ next_catch(Process* c_p, Eterm *reg) {
return NULL;
}
- /*
- * Better safe than sorry here. In debug builds, produce a core
- * dump if the top of the stack doesn't point to a continuation
- * pointer. In other builds, ignore a non-CP at the top of stack.
- */
- ASSERT(is_CP(*ptr));
- if ((is_not_CP(*ptr) || (*cp_val(*ptr) != i_return_trace &&
- *cp_val(*ptr) != i_return_to_trace &&
- *cp_val(*ptr) != i_return_time_trace ))
- && c_p->cp) {
- /* Can not follow cp here - code may be unloaded */
- BeamInstr *cpp = c_p->cp;
- if (cpp == beam_exception_trace) {
- ErtsCodeMFA *mfa = (ErtsCodeMFA*)cp_val(ptr[0]);
- erts_trace_exception(c_p, mfa,
- reg[1], reg[2],
- ERTS_TRACER_FROM_ETERM(ptr+1));
- /* Skip return_trace parameters */
- ptr += 2;
- } else if (cpp == beam_return_trace) {
- /* Skip return_trace parameters */
- ptr += 2;
- } else if (cpp == beam_return_time_trace) {
- /* Skip return_trace parameters */
- ptr += 1;
- } else if (cpp == beam_return_to_trace) {
- have_return_to_trace = !0; /* Record next cp */
- }
- }
while (ptr < STACK_START(c_p)) {
if (is_catch(*ptr)) {
if (active_catches) goto found_catch;
@@ -1664,6 +1631,57 @@ expand_error_value(Process* c_p, Uint freason, Eterm Value) {
return Value;
}
+
+static void
+gather_stacktrace(Process* p, Eterm *ptr, struct StackTrace* s, int depth)
+{
+ BeamInstr *prev;
+ BeamInstr i_return_trace;
+ BeamInstr i_return_to_trace;
+
+ if (depth == 0) {
+ return;
+ }
+
+ prev = s->depth ? s->trace[s->depth-1] : s->pc;
+ i_return_trace = beam_return_trace[0];
+ i_return_to_trace = beam_return_to_trace[0];
+
+ /*
+ * Traverse the stack backwards and add all unique continuation
+ * pointers to the buffer, up to the maximum stack trace size.
+ *
+ * Skip trace stack frames.
+ */
+
+ ASSERT(ptr >= STACK_TOP(p) && ptr <= STACK_START(p));
+
+ while (ptr < STACK_START(p) && depth > 0) {
+ if (is_CP(*ptr)) {
+ if (*cp_val(*ptr) == i_return_trace) {
+ /* Skip stack frame variables */
+ do ++ptr; while (is_not_CP(*ptr));
+ /* Skip return_trace parameters */
+ ptr += 2;
+ } else if (*cp_val(*ptr) == i_return_to_trace) {
+ /* Skip stack frame variables */
+ do ++ptr; while (is_not_CP(*ptr));
+ } else {
+ BeamInstr *cp = cp_val(*ptr);
+ if (cp != prev) {
+ /* Record non-duplicates only */
+ prev = cp;
+ s->trace[s->depth++] = cp - 1;
+ depth--;
+ }
+ ptr++;
+ }
+ } else {
+ ptr++;
+ }
+ }
+}
+
/*
* Quick-saving the stack trace in an internal form on the heap. Note
* that c_p->ftrace will point to a cons cell which holds the given args
@@ -1702,6 +1720,7 @@ static void
save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
ErtsCodeMFA *bif_mfa, Eterm args) {
struct StackTrace* s;
+ Eterm *stack_start;
int sz;
int depth = erts_backtrace_depth; /* max depth (never negative) */
@@ -1720,6 +1739,33 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
s->depth = 0;
/*
+ * If we crash on an instruction that returns to a return/exception trace
+ * instruction, we must set the stacktrace 'pc' to the actual return
+ * address or we'll lose the top stackframe when gathering the stack
+ * trace.
+ */
+ stack_start = STACK_TOP(c_p);
+ if (stack_start < STACK_START(c_p) && is_CP(*stack_start)) {
+ BeamInstr *cp = cp_val(*stack_start);
+
+ if (cp == pc) {
+ if (pc == beam_exception_trace || pc == beam_return_trace) {
+ ASSERT(&stack_start[3] <= STACK_START(c_p));
+ /* Fake having failed on the first instruction in the function
+ * pointed to by the tag. */
+ pc = cp_val(stack_start[1]);
+ stack_start += 3;
+ } else if (pc == beam_return_to_trace) {
+ ASSERT(&stack_start[2] <= STACK_START(c_p));
+ pc = cp_val(stack_start[1]);
+ /* Skip both the trace tag and the new 'pc' to avoid
+ * duplicated entries. */
+ stack_start += 2;
+ }
+ }
+ }
+
+ /*
* If the failure was in a BIF other than 'error/1', 'error/2',
* 'exit/1' or 'throw/1', save BIF-MFA and save the argument
* registers by consing up an arglist.
@@ -1750,11 +1796,6 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
s->trace[s->depth++] = pc;
depth--;
}
- /* Save second stack entry if CP is valid and different from pc */
- if (depth > 0 && c_p->cp != 0 && c_p->cp != pc) {
- s->trace[s->depth++] = c_p->cp - 1;
- depth--;
- }
s->pc = NULL;
args = make_arglist(c_p, reg, bif_mfa->arity); /* Overwrite CAR(c_p->ftrace) */
} else {
@@ -1762,9 +1803,9 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
non_bif_stacktrace:
s->current = c_p->current;
- /*
+ /*
* For a function_clause error, the arguments are in the beam
- * registers, c_p->cp is valid, and c_p->current is set.
+ * registers and c_p->current is set.
*/
if ( (GET_EXC_INDEX(s->freason)) ==
(GET_EXC_INDEX(EXC_FUNCTION_CLAUSE)) ) {
@@ -1772,18 +1813,8 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
ASSERT(s->current);
a = s->current->arity;
args = make_arglist(c_p, reg, a); /* Overwrite CAR(c_p->ftrace) */
- /* Save first stack entry */
- ASSERT(c_p->cp);
- if (depth > 0) {
- s->trace[s->depth++] = c_p->cp - 1;
- depth--;
- }
s->pc = NULL; /* Ignore pc */
} else {
- if (depth > 0 && c_p->cp != 0 && c_p->cp != pc) {
- s->trace[s->depth++] = c_p->cp - 1;
- depth--;
- }
s->pc = pc;
}
}
@@ -1796,80 +1827,13 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
}
/* Save the actual stack trace */
- erts_save_stacktrace(c_p, s, depth);
+ gather_stacktrace(c_p, stack_start, s, depth);
}
void
erts_save_stacktrace(Process* p, struct StackTrace* s, int depth)
{
- if (depth > 0) {
- Eterm *ptr;
- BeamInstr *prev = s->depth ? s->trace[s->depth-1] : NULL;
- BeamInstr i_return_trace = beam_return_trace[0];
- BeamInstr i_return_to_trace = beam_return_to_trace[0];
-
- /*
- * Traverse the stack backwards and add all unique continuation
- * pointers to the buffer, up to the maximum stack trace size.
- *
- * Skip trace stack frames.
- */
- ptr = p->stop;
- if (ptr < STACK_START(p) &&
- (is_not_CP(*ptr)|| (*cp_val(*ptr) != i_return_trace &&
- *cp_val(*ptr) != i_return_to_trace)) &&
- p->cp) {
- /* Cannot follow cp here - code may be unloaded */
- BeamInstr *cpp = p->cp;
- int trace_cp;
- if (cpp == beam_exception_trace || cpp == beam_return_trace) {
- /* Skip return_trace parameters */
- ptr += 2;
- trace_cp = 1;
- } else if (cpp == beam_return_to_trace) {
- /* Skip return_to_trace parameters */
- ptr += 1;
- trace_cp = 1;
- }
- else {
- trace_cp = 0;
- }
- if (trace_cp && s->pc == cpp) {
- /*
- * If process 'cp' points to a return/exception trace
- * instruction and 'cp' has been saved as 'pc' in
- * stacktrace, we need to update 'pc' in stacktrace
- * with the actual 'cp' located on the top of the
- * stack; otherwise, we will lose the top stackframe
- * when building the stack trace.
- */
- ASSERT(is_CP(p->stop[0]));
- s->pc = cp_val(p->stop[0]);
- }
- }
- while (ptr < STACK_START(p) && depth > 0) {
- if (is_CP(*ptr)) {
- if (*cp_val(*ptr) == i_return_trace) {
- /* Skip stack frame variables */
- do ++ptr; while (is_not_CP(*ptr));
- /* Skip return_trace parameters */
- ptr += 2;
- } else if (*cp_val(*ptr) == i_return_to_trace) {
- /* Skip stack frame variables */
- do ++ptr; while (is_not_CP(*ptr));
- } else {
- BeamInstr *cp = cp_val(*ptr);
- if (cp != prev) {
- /* Record non-duplicates only */
- prev = cp;
- s->trace[s->depth++] = cp - 1;
- depth--;
- }
- ptr++;
- }
- } else ptr++;
- }
- }
+ gather_stacktrace(p, STACK_TOP(p), s, depth);
}
/*
@@ -2144,36 +2108,33 @@ apply_bif_error_adjustment(Process *p, Export *ep,
* erlang:error/1, erlang:error/2, erlang:exit/1,
* or erlang:throw/1. Error handling of these BIFs is
* special!
+ *
+ * We need the topmost continuation pointer to point into the
+ * calling function when handling the error after the BIF has
+ * been applied. This in order to get the topmost stackframe
+ * correct.
*
- * We need 'p->cp' to point into the calling
- * function when handling the error after the BIF has
- * been applied. This in order to get the topmost
- * stackframe correct. Without the following adjustment,
- * 'p->cp' will point into the function that called
- * current function when handling the error. We add a
- * dummy stackframe in order to achieve this.
- *
- * Note that these BIFs unconditionally will cause
- * an exception to be raised. That is, our modifications
- * of 'p->cp' as well as the stack will be corrected by
- * the error handling code.
- *
- * If we find an exception/return-to trace continuation
- * pointer as the topmost continuation pointer, we do not
- * need to do anything since the information already will
- * be available for generation of the stacktrace.
+ * Note that these BIFs will unconditionally cause an
+ * exception to be raised. That is, our modifications of the
+ * stack will be corrected by the error handling code.
*/
int apply_only = stack_offset == 0;
BeamInstr *cpp;
+ Eterm *E;
- if (apply_only) {
- ASSERT(p->cp != NULL);
- cpp = p->cp;
- }
- else {
- ASSERT(is_CP(p->stop[0]));
- cpp = cp_val(p->stop[0]);
- }
+ E = p->stop;
+
+ while (is_not_CP(*E)) {
+ E++;
+ }
+ cpp = cp_val(E[0]);
+
+ /*
+ * If we find an exception/return-to trace continuation
+ * pointer as the topmost continuation pointer, we do not
+ * need to do anything since the information will already
+ * be available for generation of the stacktrace.
+ */
if (cpp != beam_exception_trace
&& cpp != beam_return_trace
@@ -2183,38 +2144,29 @@ apply_bif_error_adjustment(Process *p, Export *ep,
need = 1; /* i_apply_only */
if (p->stop - p->htop < need)
erts_garbage_collect(p, (int) need, reg, arity+1);
- p->stop -= need;
-
if (apply_only) {
/*
* Called from the i_apply_only instruction.
*
- * 'p->cp' contains continuation pointer pointing
- * into the function that called current function.
- * We push that continuation pointer onto the stack,
- * and set 'p->cp' to point into current function.
+ * Push the continuation pointer for the current
+ * function to the stack.
*/
-
- p->stop[0] = make_cp(p->cp);
- p->cp = I;
- }
- else {
+ p->stop -= need;
+ p->stop[0] = make_cp(I);
+ } else {
/*
- * Called from an i_apply_last_p, or apply_last_IP,
- * instruction.
- *
- * Calling instruction will after we return read
- * a continuation pointer from the stack and write
- * it to 'p->cp', and then remove the topmost
- * stackframe of size 'stack_offset'.
+ * Called from an i_apply_last_* instruction.
*
- * We have sized the dummy-stackframe so that it
- * will be removed by the instruction we currently
- * are executing, and leave the stackframe that
- * normally would have been removed intact.
+ * The calling instruction will deallocate a stack
+ * frame of size 'stack_offset'.
*
+ * Push the continuation pointer for the current
+ * function to the stack, and then add a dummy
+ * stackframe for the i_apply_last* instruction
+ * to discard.
*/
- p->stop[0] = make_cp(I);
+ p->stop[0] = make_cp(I);
+ p->stop -= need;
}
}
}
@@ -2437,10 +2389,10 @@ erts_hibernate(Process* c_p, Eterm* reg)
c_p->arg_reg[0] = module;
c_p->arg_reg[1] = function;
c_p->arg_reg[2] = args;
- c_p->stop = STACK_START(c_p);
+ c_p->stop = c_p->hend - 1; /* Keep first continuation pointer */
+ ASSERT(c_p->stop[0] == make_cp(beam_apply+1));
c_p->catches = 0;
c_p->i = beam_apply;
- c_p->cp = (BeamInstr *) beam_apply+1;
/*
* If there are no waiting messages, garbage collect and
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index 9f67f46b31..7afbbfd894 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -5164,7 +5164,7 @@ erts_schedule_bif(Process *proc,
else if (proc->flags & F_HIPE_MODE) {
/* Pointer to bif export in i */
exp = (Export *) i;
- pc = c_p->cp;
+ pc = cp_val(c_p->stop[0]);
mfa = &exp->info.mfa;
}
#endif
@@ -5181,8 +5181,7 @@ erts_schedule_bif(Process *proc,
mfa = &exp->info.mfa;
}
else if (BeamIsOpCode(*i, op_apply_bif)) {
- /* Pointer to bif in i+1, and mfa in i-3 */
- pc = c_p->cp;
+ pc = cp_val(c_p->stop[0]);
mfa = erts_code_to_codemfa(i);
}
else {
@@ -5273,7 +5272,6 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
dirty_shadow_proc->freason = c_p->freason;
dirty_shadow_proc->fvalue = c_p->fvalue;
dirty_shadow_proc->ftrace = c_p->ftrace;
- dirty_shadow_proc->cp = c_p->cp;
dirty_shadow_proc->i = c_p->i;
#ifdef DEBUG
@@ -5320,7 +5318,6 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
c_p->freason = dirty_shadow_proc->freason;
c_p->fvalue = dirty_shadow_proc->fvalue;
c_p->ftrace = dirty_shadow_proc->ftrace;
- c_p->cp = dirty_shadow_proc->cp;
c_p->i = dirty_shadow_proc->i;
c_p->arity = dirty_shadow_proc->arity;
}
diff --git a/erts/emulator/beam/bif_instrs.tab b/erts/emulator/beam/bif_instrs.tab
index 8e0caa38a3..f1877882a1 100644
--- a/erts/emulator/beam/bif_instrs.tab
+++ b/erts/emulator/beam/bif_instrs.tab
@@ -280,7 +280,7 @@ call_bif(Exp) {
* erlang code or by nif_bif.epilogue() when the BIF
* is done).
*/
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
SET_I(c_p->i);
SWAPIN;
Dispatch();
@@ -297,7 +297,7 @@ call_bif(Exp) {
//
// Call a BIF tail-recursively, storing the result in x(0) and doing
-// a return to the continuation poiner (c_p->cp).
+// a return to the continuation poiner.
//
call_bif_only(Exp) {
@@ -367,7 +367,7 @@ call_bif_only(Exp) {
} else if (c_p->freason == TRAP) {
/*
* Dispatch to a trap. When the trap is done, a jump
- * to the continuation pointer (c_p->cp) will be done.
+ * to the continuation pointer on the stack will be done.
*/
SET_I(c_p->i);
SWAPIN;
@@ -413,7 +413,7 @@ send() {
r(0) = result;
CHECK_TERM(r(0));
} else if (c_p->freason == TRAP) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
SET_I(c_p->i);
SWAPIN;
Dispatch();
@@ -570,8 +570,7 @@ nif_bif.epilogue() {
if (ERTS_LIKELY(is_value(nif_bif_result))) {
r(0) = nif_bif_result;
CHECK_TERM(r(0));
- SET_I(c_p->cp);
- c_p->cp = 0;
+ $RETURN();
Goto(*I);
} else if (c_p->freason == TRAP) {
SET_I(c_p->i);
@@ -581,6 +580,10 @@ nif_bif.epilogue() {
}
Dispatch();
}
- I = handle_error(c_p, c_p->cp, reg, c_p->current);
+ {
+ BeamInstr *cp = cp_val(*E);
+ ASSERT(VALID_INSTR(*cp));
+ I = handle_error(c_p, cp, reg, c_p->current);
+ }
goto post_error_handling;
}
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index aa55bdab6a..dd616645dc 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -2008,14 +2008,16 @@ current_function(Process *c_p, ErtsHeapFactory *hfact, Process* rp,
if (c_p == rp && !(flags & ERTS_PI_FLAG_REQUEST_FOR_OTHER)) {
FunctionInfo fi2;
+ BeamInstr* continuation_ptr;
/*
* The current function is erlang:process_info/{1,2},
* which is not the answer that the application want.
- * We will use the function pointed into by rp->cp
- * instead if it can be looked up.
+ * We will use the continuation pointer stored at the
+ * top of the stack instead.
*/
- erts_lookup_function_info(&fi2, rp->cp, full_info);
+ continuation_ptr = (BeamInstr *) rp->stop[0];
+ erts_lookup_function_info(&fi2, continuation_ptr, full_info);
if (fi2.mfa) {
fi = fi2;
rp->current = fi2.mfa;
@@ -2062,10 +2064,6 @@ current_stacktrace(ErtsHeapFactory *hfact, Process* rp,
s->trace[s->depth++] = rp->i;
depth--;
}
- if (depth > 0 && rp->cp != 0) {
- s->trace[s->depth++] = rp->cp - 1;
- depth--;
- }
erts_save_stacktrace(rp, s, depth);
depth = s->depth;
diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index 1ea7074d21..6a48f5c74e 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -2612,7 +2612,10 @@ restart:
break;
case matchCaller:
ASSERT(c_p == self);
- if (!(c_p->cp) || !(cp = find_function_from_pc(c_p->cp))) {
+ t = c_p->stop[0];
+ if (is_not_CP(t)) {
+ *esp++ = am_undefined;
+ } else if (!(cp = find_function_from_pc(cp_val(t)))) {
*esp++ = am_undefined;
} else {
ehp = HAllocX(build_proc, 4, HEAP_XTRA);
@@ -5226,7 +5229,7 @@ static Eterm match_spec_test(Process *p, Eterm against, Eterm spec, int trace)
Eterm l;
Uint32 ret_flags;
Uint sz;
- BeamInstr *save_cp;
+ Eterm save_cp;
if (trace && !(is_list(against) || against == NIL)) {
return THE_NON_VALUE;
@@ -5270,13 +5273,13 @@ static Eterm match_spec_test(Process *p, Eterm against, Eterm spec, int trace)
++n;
l = CDR(list_val(l));
}
- save_cp = p->cp;
- p->cp = NULL;
+ save_cp = p->stop[0];
+ p->stop[0] = NIL;
res = erts_match_set_run_trace(p, p,
mps, arr, n,
ERTS_PAM_COPY_RESULT|ERTS_PAM_IGNORE_TRACE_SILENT,
&ret_flags);
- p->cp = save_cp;
+ p->stop[0] = save_cp;
} else {
n = 0;
arr = NULL;
diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index 13b1f8ab4d..f387960b08 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -65,6 +65,8 @@
# define HARDDEBUG 1
#endif
+extern BeamInstr beam_apply[2];
+
/*
* Returns number of elements in an array.
*/
@@ -934,13 +936,15 @@ garbage_collect_hibernate(Process* p, int check_long_gc)
*/
erts_atomic32_read_bor_nob(&p->state, ERTS_PSFLG_GC);
ErtsGcQuickSanityCheck(p);
- ASSERT(p->stop == p->hend); /* Stack must be empty. */
+ ASSERT(p->stop == p->hend - 1); /* Only allow one continuation pointer. */
+ ASSERT(p->stop[0] == make_cp(beam_apply+1));
/*
* Do it.
*/
heap_size = p->heap_sz + (p->old_htop - p->old_heap) + p->mbuf_sz;
+ heap_size += 1; /* Reserve place for continuation pointer */
heap = (Eterm*) ERTS_HEAP_ALLOC(ERTS_ALC_T_TMP_HEAP,
sizeof(Eterm)*heap_size);
@@ -966,13 +970,11 @@ garbage_collect_hibernate(Process* p, int check_long_gc)
p->high_water = htop;
p->htop = htop;
p->hend = p->heap + heap_size;
- p->stop = p->hend;
+ p->stop = p->hend - 1;
p->heap_sz = heap_size;
heap_size = actual_size = p->htop - p->heap;
- if (heap_size == 0) {
- heap_size = 1; /* We want a heap... */
- }
+ heap_size += 1; /* Reserve place for continuation pointer */
FLAGS(p) &= ~F_FORCE_GC;
p->live_hf_end = ERTS_INVALID_HFRAG_PTR;
@@ -988,14 +990,15 @@ garbage_collect_hibernate(Process* p, int check_long_gc)
* hibernated.
*/
- ASSERT(p->hend - p->stop == 0); /* Empty stack */
ASSERT(actual_size < p->heap_sz);
heap = ERTS_HEAP_ALLOC(ERTS_ALC_T_HEAP, sizeof(Eterm)*heap_size);
sys_memcpy((void *) heap, (void *) p->heap, actual_size*sizeof(Eterm));
ERTS_HEAP_FREE(ERTS_ALC_T_TMP_HEAP, p->heap, p->heap_sz*sizeof(Eterm));
- p->stop = p->hend = heap + heap_size;
+ p->hend = heap + heap_size;
+ p->stop = p->hend - 1;
+ p->stop[0] = make_cp(beam_apply+1);
offs = heap - p->heap;
area = (char *) p->heap;
diff --git a/erts/emulator/beam/erl_nfunc_sched.c b/erts/emulator/beam/erl_nfunc_sched.c
index b8cf2bee0e..b2658ef180 100644
--- a/erts/emulator/beam/erl_nfunc_sched.c
+++ b/erts/emulator/beam/erl_nfunc_sched.c
@@ -67,7 +67,7 @@ erts_destroy_nif_export(Process *p)
void
erts_nif_export_save_trace(Process *c_p, NifExport *nep, int applying,
- Export* ep, BeamInstr *cp, Uint32 flags,
+ Export* ep, Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer)
{
@@ -78,7 +78,6 @@ erts_nif_export_save_trace(Process *c_p, NifExport *nep, int applying,
sizeof(NifExportTrace));
netp->applying = applying;
netp->ep = ep;
- netp->cp = cp;
netp->flags = flags;
netp->flags_meta = flags_meta;
netp->I = I;
@@ -93,7 +92,7 @@ erts_nif_export_restore_trace(Process *c_p, Eterm result, NifExport *nep)
NifExportTrace *netp = nep->trace;
nep->trace = NULL;
erts_bif_trace_epilogue(c_p, result, netp->applying, netp->ep,
- netp->cp, netp->flags, netp->flags_meta,
+ netp->flags, netp->flags_meta,
netp->I, netp->meta_tracer);
erts_tracer_update(&netp->meta_tracer, NIL);
erts_free(ERTS_ALC_T_NIF_EXP_TRACE, netp);
@@ -148,7 +147,6 @@ erts_nif_export_schedule(Process *c_p, Process *dirty_shadow_proc,
for (i = 0; i < (int) mfa->arity; i++)
nep->argv[i] = reg[i];
nep->pc = pc;
- nep->cp = c_p->cp;
nep->mfa = mfa;
nep->current = c_p->current;
ASSERT(argc >= 0);
diff --git a/erts/emulator/beam/erl_nfunc_sched.h b/erts/emulator/beam/erl_nfunc_sched.h
index 1cb252eba5..5c6486cbb8 100644
--- a/erts/emulator/beam/erl_nfunc_sched.h
+++ b/erts/emulator/beam/erl_nfunc_sched.h
@@ -28,7 +28,6 @@
typedef struct {
int applying;
Export* ep;
- BeamInstr *cp;
Uint32 flags;
Uint32 flags_meta;
BeamInstr* I;
@@ -53,7 +52,6 @@ typedef struct {
NifExportTrace *trace;
/* --- The following is only used on error --- */
BeamInstr *pc; /* Program counter */
- BeamInstr *cp; /* Continuation pointer */
ErtsCodeMFA *mfa; /* MFA of original call */
int argc; /* Number of arguments in original call */
int argv_size; /* Allocated size of argv */
@@ -62,7 +60,7 @@ typedef struct {
NifExport *erts_new_proc_nif_export(Process *c_p, int argc);
void erts_nif_export_save_trace(Process *c_p, NifExport *nep, int applying,
- Export* ep, BeamInstr *cp, Uint32 flags,
+ Export* ep, Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer);
void erts_nif_export_restore_trace(Process *c_p, Eterm result, NifExport *nep);
@@ -85,7 +83,7 @@ ERTS_GLB_INLINE void erts_nif_export_restore_error(Process* c_p, BeamInstr **pc,
Eterm *reg, ErtsCodeMFA **nif_mfa);
ERTS_GLB_INLINE int erts_nif_export_check_save_trace(Process *c_p, Eterm result,
int applying, Export* ep,
- BeamInstr *cp, Uint32 flags,
+ Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer);
ERTS_GLB_INLINE Process *erts_proc_shadow2real(Process *c_p);
@@ -131,8 +129,6 @@ erts_check_nif_export_in_area(Process *p, char *start, Uint size)
return 0;
if (ErtsInArea(nep->pc, start, size))
return 1;
- if (ErtsInArea(nep->cp, start, size))
- return 1;
if (ErtsInArea(nep->mfa, start, size))
return 1;
if (ErtsInArea(nep->current, start, size))
@@ -164,7 +160,6 @@ erts_nif_export_restore_error(Process* c_p, BeamInstr **pc,
ASSERT(nep);
*pc = nep->pc;
- c_p->cp = nep->cp;
*nif_mfa = nep->mfa;
for (ix = 0; ix < nep->argc; ix++)
reg[ix] = nep->argv[ix];
@@ -174,7 +169,7 @@ erts_nif_export_restore_error(Process* c_p, BeamInstr **pc,
ERTS_GLB_INLINE int
erts_nif_export_check_save_trace(Process *c_p, Eterm result,
int applying, Export* ep,
- BeamInstr *cp, Uint32 flags,
+ Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer)
{
@@ -182,7 +177,7 @@ erts_nif_export_check_save_trace(Process *c_p, Eterm result,
NifExport *nep = ERTS_PROC_GET_NIF_TRAP_EXPORT(c_p);
if (nep && nep->argc >= 0) {
erts_nif_export_save_trace(c_p, nep, applying, ep,
- cp, flags, flags_meta,
+ flags, flags_meta,
I, meta_tracer);
return 1;
}
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index ce43cb9e71..46f7e864fd 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -334,7 +334,7 @@ schedule(ErlNifEnv* env, NativeFunPtr direct_fp, NativeFunPtr indirect_fp,
ep = erts_nif_export_schedule(c_p, dirty_shadow_proc,
c_p->current,
- c_p->cp,
+ cp_val(c_p->stop[0]),
BeamOpCodeAddr(op_call_nif),
direct_fp, indirect_fp,
mod, func_name,
@@ -4117,7 +4117,6 @@ static struct erl_module_nif* create_lib(const ErlNifEntry* src)
return lib;
};
-
BIF_RETTYPE load_nif_2(BIF_ALIST_2)
{
static const char bad_lib[] = "bad_lib";
@@ -4140,6 +4139,7 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
struct erl_module_nif* lib = NULL;
struct erl_module_instance* this_mi;
struct erl_module_instance* prev_mi;
+ BeamInstr* caller_cp;
if (BIF_P->flags & F_HIPE_MODE) {
ret = load_nif_error(BIF_P, "notsup", "Calling load_nif from HiPE compiled "
@@ -4175,7 +4175,8 @@ BIF_RETTYPE load_nif_2(BIF_ALIST_2)
ASSERT(BIF_P->current->module == am_erlang
&& BIF_P->current->function == am_load_nif
&& BIF_P->current->arity == 2);
- caller = find_function_from_pc(BIF_P->cp);
+ caller_cp = cp_val(BIF_P->stop[0]);
+ caller = find_function_from_pc(caller_cp);
ASSERT(caller != NULL);
mod_atom = caller->module;
ASSERT(is_atom(mod_atom));
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index e8c83276f5..4b4337ce17 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -11458,7 +11458,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
#else
arg_size = size_object_litopt(args, &litarea);
#endif
- heap_need = arg_size;
+ heap_need = arg_size + 1; /* Reserve place for continuation pointer */
p->flags = flags;
@@ -11507,7 +11507,8 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
p->old_hend = p->old_htop = p->old_heap = NULL;
p->high_water = p->heap;
p->gen_gcs = 0;
- p->stop = p->hend = p->heap + sz;
+ p->hend = p->heap + sz;
+ p->stop = p->hend - 1; /* Reserve place for continuation pointer */
p->htop = p->heap;
p->heap_sz = sz;
p->abandoned_heap = NULL;
@@ -11525,7 +11526,7 @@ erl_create_process(Process* parent, /* Parent of process (default group leader).
p->current = &p->u.initial;
p->i = (BeamInstr *) beam_apply;
- p->cp = (BeamInstr *) beam_apply+1;
+ p->stop[0] = make_cp(beam_apply + 1);
p->arg_reg = p->def_arg_reg;
p->max_arg_reg = sizeof(p->def_arg_reg)/sizeof(p->def_arg_reg[0]);
@@ -11839,7 +11840,6 @@ void erts_init_empty_process(Process *p)
p->u.initial.function = 0;
p->u.initial.arity = 0;
p->catches = 0;
- p->cp = NULL;
p->i = NULL;
p->current = NULL;
@@ -11917,7 +11917,6 @@ erts_debug_verify_clean_empty_process(Process* p)
ASSERT(p->bif_timers == NULL);
ASSERT(p->dictionary == NULL);
ASSERT(p->catches == 0);
- ASSERT(p->cp == NULL);
ASSERT(p->i == NULL);
ASSERT(p->current == NULL);
@@ -13146,9 +13145,6 @@ erts_program_counter_info(fmtfn_t to, void *to_arg, Process *p)
erts_print(to, to_arg, "Program counter: %p (", p->i);
print_function_from_pc(to, to_arg, p->i);
erts_print(to, to_arg, ")\n");
- erts_print(to, to_arg, "CP: %p (", p->cp);
- print_function_from_pc(to, to_arg, p->cp);
- erts_print(to, to_arg, ")\n");
state = erts_atomic32_read_acqb(&p->state);
if (!(state & (ERTS_PSFLG_RUNNING
| ERTS_PSFLG_RUNNING_SYS
@@ -13425,9 +13421,6 @@ static void print_current_process_info(fmtfn_t to, void *to_arg,
erts_print(to, to_arg, "Current Process Program counter: %p (", p->i);
print_function_from_pc(to, to_arg, p->i);
erts_print(to, to_arg, ")\n");
- erts_print(to, to_arg, "Current Process CP: %p (", p->cp);
- print_function_from_pc(to, to_arg, p->cp);
- erts_print(to, to_arg, ")\n");
/* Getting this stacktrace can segfault if we are very very
unlucky if called while a process is being garbage collected.
diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 405611c584..a7a6528f92 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -975,7 +975,6 @@ struct process {
unsigned max_arg_reg; /* Maximum number of argument registers available. */
Eterm def_arg_reg[6]; /* Default array for argument registers. */
- BeamInstr* cp; /* (untagged) Continuation pointer (for threaded code). */
BeamInstr* i; /* Program counter for threaded code. */
Sint catches; /* Number of catches on stack */
Sint fcalls; /*
diff --git a/erts/emulator/beam/erl_trace.h b/erts/emulator/beam/erl_trace.h
index d25f97c656..f564549ab9 100644
--- a/erts/emulator/beam/erl_trace.h
+++ b/erts/emulator/beam/erl_trace.h
@@ -145,7 +145,7 @@ int erts_trace_flags(Eterm List,
Eterm erts_bif_trace(int bif_index, Process* p, Eterm* args, BeamInstr *I);
Eterm
erts_bif_trace_epilogue(Process *p, Eterm result, int applying,
- Export* ep, BeamInstr *cp, Uint32 flags,
+ Export* ep, Uint32 flags,
Uint32 flags_meta, BeamInstr* I,
ErtsTracer meta_tracer);
diff --git a/erts/emulator/beam/instrs.tab b/erts/emulator/beam/instrs.tab
index bc8c1189a8..efdba73057 100644
--- a/erts/emulator/beam/instrs.tab
+++ b/erts/emulator/beam/instrs.tab
@@ -19,7 +19,12 @@
// %CopyrightEnd%
//
-// Stack manipulation instructions
+//
+// Stack manipulation instructions follow.
+//
+// See the comment for AH() in macros.tab for information about
+// the layout of stack frames.
+//
allocate(NeedStack, Live) {
$AH($NeedStack, 0, $Live);
@@ -58,15 +63,14 @@ allocate_heap_zero(NeedStack, NeedHeap, Live) {
deallocate(Deallocate) {
//| -no_prefetch
- SET_CP(c_p, (BeamInstr *) cp_val(*E));
E = ADD_BYTE_OFFSET(E, $Deallocate);
}
deallocate_return(Deallocate) {
//| -no_next
int words_to_pop = $Deallocate;
- SET_I((BeamInstr *) cp_val(*E));
E = ADD_BYTE_OFFSET(E, words_to_pop);
+ $RETURN();
CHECK_TERM(x(0));
DispatchReturn;
}
@@ -93,13 +97,13 @@ DISPATCH_ABS(CallDest) {
}
i_call(CallDest) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCH_REL($CallDest);
}
move_call(Src, CallDest) {
x(0) = $Src;
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCH_REL($CallDest);
}
@@ -131,7 +135,7 @@ DISPATCHX(Dest) {
}
i_call_ext(Dest) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCHX($Dest);
}
@@ -175,7 +179,7 @@ i_apply() {
BeamInstr *next;
$APPLY(NULL, 0, next);
if (ERTS_LIKELY(next != NULL)) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCH_ABS(next);
}
$HANDLE_APPLY_ERROR();
@@ -211,7 +215,7 @@ apply(Arity) {
BeamInstr *next;
$FIXED_APPLY($Arity, NULL, 0, next);
if (ERTS_LIKELY(next != NULL)) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCH_ABS(next);
}
$HANDLE_APPLY_ERROR();
@@ -247,7 +251,7 @@ i_apply_fun() {
BeamInstr *next;
$APPLY_FUN(next);
if (ERTS_LIKELY(next != NULL)) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCH_FUN(next);
}
$HANDLE_APPLY_FUN_ERROR();
@@ -283,7 +287,7 @@ i_call_fun(Fun) {
BeamInstr *next;
$CALL_FUN($Fun, next);
if (ERTS_LIKELY(next != NULL)) {
- SET_CP(c_p, $NEXT_INSTRUCTION);
+ $SAVE_CONTINUATION_POINTER($NEXT_INSTRUCTION);
$DISPATCH_FUN(next);
}
$HANDLE_APPLY_FUN_ERROR();
@@ -301,15 +305,8 @@ i_call_fun_last(Fun, Deallocate) {
return() {
//| -no_next
- SET_I(c_p->cp);
+ $RETURN();
DTRACE_RETURN_FROM_PC(c_p);
-
- /*
- * We must clear the CP to make sure that a stale value do not
- * create a false module dependcy preventing code upgrading.
- * It also means that we can use the CP in stack backtraces.
- */
- c_p->cp = 0;
CHECK_TERM(r(0));
HEAP_SPACE_VERIFIED(0);
DispatchReturn;
@@ -478,16 +475,21 @@ i_make_fun(FunP, NumFree) {
}
move_trim(Src, Dst, Words) {
- Uint cp = E[0];
$Dst = $Src;
- E += $Words;
- E[0] = cp;
+ $i_trim($Words);
}
i_trim(Words) {
- Uint cp = E[0];
E += $Words;
- E[0] = cp;
+
+ /*
+ * Clear the reserved location for the continuation pointer at
+ * E[0]. This is not strictly necessary for correctness, but if a
+ * GC is triggered before E[0] is overwritten by another
+ * continuation pointer the now dead term at E[0] would be
+ * retained by the GC.
+ */
+ E[0] = NIL;
}
move(Src, Dst) {
@@ -599,8 +601,7 @@ move_window5(S1, S2, S3, S4, S5, D) {
move_return(Src) {
//| -no_next
x(0) = $Src;
- SET_I(c_p->cp);
- c_p->cp = 0;
+ $RETURN();
DispatchReturn;
}
diff --git a/erts/emulator/beam/macros.tab b/erts/emulator/beam/macros.tab
index 1b5e5f66b0..9d183e1f41 100644
--- a/erts/emulator/beam/macros.tab
+++ b/erts/emulator/beam/macros.tab
@@ -104,14 +104,52 @@ GC_TEST_PRESERVE(NeedHeap, Live, PreserveTerm) {
// Make sure that there are NeedStack + NeedHeap + 1 words available
-// on the combined heap/stack segment, then allocates NeedHeap + 1
-// words on the stack and saves CP.
+// on the combined heap/stack segment, then decrement the stack
+// pointer by (NeedStack + 1) words. Finally clear the word reserved
+// for the continuation pointer at the top of the stack.
+//
+// Stack frame layout:
+//
+// +-----------+
+// y(N) | Term |
+// +-----------+
+// .
+// .
+// .
+// +-----------+
+// y(0) | Term |
+// +-----------+
+// E ==> | NIL or CP |
+// +-----------+
+//
+// When the function owning the stack frame is the currently executing
+// function, the word at the top of the stack is NIL. When calling
+// another function, the continuation pointer will be stored in the
+// word at the top of the stack. When returning to the function
+// owning the stack frame, the word at the stack top will again be set
+// to NIL.
+
AH(NeedStack, NeedHeap, Live) {
unsigned needed = $NeedStack + 1;
$GC_TEST(needed, $NeedHeap, $Live);
E -= needed;
- *E = make_cp(c_p->cp);
- c_p->cp = 0;
+ *E = NIL;
+}
+
+// Save the continuation pointer in the reserved slot at the
+// top of the stack as preparation for doing a function call.
+
+SAVE_CONTINUATION_POINTER(IP) {
+ ASSERT(VALID_INSTR(*($IP)));
+ *E = (BeamInstr) ($IP);
+}
+
+// Return to the function whose continuation pointer is stored
+// at the top of the stack and set that word to NIL.
+
+RETURN() {
+ SET_I(cp_val(*E));
+ *E = NIL;
}
NEXT0() {
diff --git a/erts/emulator/beam/trace_instrs.tab b/erts/emulator/beam/trace_instrs.tab
index 3eee81c053..9f22587f96 100644
--- a/erts/emulator/beam/trace_instrs.tab
+++ b/erts/emulator/beam/trace_instrs.tab
@@ -20,16 +20,15 @@
//
return_trace() {
- ErtsCodeMFA* mfa = (ErtsCodeMFA *)(E[0]);
+ ErtsCodeMFA* mfa = (ErtsCodeMFA *)(E[1]);
SWAPOUT; /* Needed for shared heap */
ERTS_UNREQ_PROC_MAIN_LOCK(c_p);
- erts_trace_return(c_p, mfa, r(0), ERTS_TRACER_FROM_ETERM(E+1)/* tracer */);
+ erts_trace_return(c_p, mfa, r(0), ERTS_TRACER_FROM_ETERM(E+2)/* tracer */);
ERTS_REQ_PROC_MAIN_LOCK(c_p);
SWAPIN;
- c_p->cp = NULL;
- SET_I((BeamInstr *) cp_val(E[2]));
E += 3;
+ $RETURN();
Goto(*I);
//| -no_next
}
@@ -45,13 +44,12 @@ i_generic_breakpoint() {
}
i_return_time_trace() {
- BeamInstr *pc = (BeamInstr *) (UWord) E[0];
+ BeamInstr *pc = (BeamInstr *) (UWord) E[1];
SWAPOUT;
erts_trace_time_return(c_p, erts_code_to_codeinfo(pc));
SWAPIN;
- c_p->cp = NULL;
- SET_I((BeamInstr *) cp_val(E[1]));
E += 2;
+ $RETURN();
Goto(*I);
//| -no_next
}
@@ -59,8 +57,10 @@ i_return_time_trace() {
i_return_to_trace() {
if (IS_TRACED_FL(c_p, F_TRACE_RETURN_TO)) {
Uint *cpp = (Uint*) E;
+ while (is_not_CP(*cpp)) {
+ cpp++;
+ }
for(;;) {
- ASSERT(is_CP(*cpp));
if (IsOpCode(*cp_val(*cpp), return_trace)) {
do
++cpp;
@@ -80,9 +80,8 @@ i_return_to_trace() {
ERTS_REQ_PROC_MAIN_LOCK(c_p);
SWAPIN;
}
- c_p->cp = NULL;
- SET_I((BeamInstr *) cp_val(E[0]));
E += 1;
+ $RETURN();
Goto(*I);
//| -no_next
}
diff --git a/erts/emulator/hipe/hipe_debug.c b/erts/emulator/hipe/hipe_debug.c
index 138e4f7da3..2e34cfac59 100644
--- a/erts/emulator/hipe/hipe_debug.c
+++ b/erts/emulator/hipe/hipe_debug.c
@@ -232,7 +232,6 @@ void hipe_print_pcb(Process *p)
U("intial.fun ", u.initial.function);
U("intial.ari ", u.initial.arity);
U("current ", current);
- P("cp ", cp);
P("i ", i);
U("catches ", catches);
U("arity ", arity);
diff --git a/erts/emulator/hipe/hipe_instrs.tab b/erts/emulator/hipe/hipe_instrs.tab
index a01baebddf..62162fcb9c 100644
--- a/erts/emulator/hipe/hipe_instrs.tab
+++ b/erts/emulator/hipe/hipe_instrs.tab
@@ -86,8 +86,7 @@ hipe_trap.post() {
switch( c_p->def_arg_reg[3] ) {
case HIPE_MODE_SWITCH_RES_RETURN:
ASSERT(is_value(reg[0]));
- SET_I(c_p->cp);
- c_p->cp = 0;
+ $RETURN();
Goto(*I);
case HIPE_MODE_SWITCH_RES_CALL_EXPORTED:
c_p->i = c_p->hipe.u.callee_exp->addressv[erts_active_code_ix()];
@@ -111,7 +110,6 @@ hipe_trap.post() {
goto find_func_info;
}
case HIPE_MODE_SWITCH_RES_THROW:
- c_p->cp = NULL;
I = handle_error(c_p, I, reg, NULL);
goto post_error_handling;
default:
diff --git a/erts/emulator/hipe/hipe_mode_switch.c b/erts/emulator/hipe/hipe_mode_switch.c
index 052cf9c263..863c5e6d44 100644
--- a/erts/emulator/hipe/hipe_mode_switch.c
+++ b/erts/emulator/hipe/hipe_mode_switch.c
@@ -202,15 +202,13 @@ hipe_push_beam_trap_frame(Process *p, Eterm reg[], unsigned arity)
p->stop -= 2;
p->stop[1] = hipe_beam_catch_throw;
}
- p->stop[0] = make_cp(p->cp);
+ p->stop[0] = (BeamInstr) hipe_beam_pc_return;
++p->catches;
- p->cp = hipe_beam_pc_return;
}
static __inline__ void hipe_pop_beam_trap_frame(Process *p)
{
ASSERT(p->stop[1] == hipe_beam_catch_throw);
- p->cp = cp_val(p->stop[0]);
--p->catches;
p->stop += 2;
}
@@ -263,7 +261,7 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
unsigned arity = cmd >> 8;
/* p->hipe.u.ncallee set in beam_emu */
- if (p->cp == hipe_beam_pc_return) {
+ if (cp_val(p->stop[0]) == hipe_beam_pc_return) {
/* Native called BEAM, which now tailcalls native. */
hipe_pop_beam_trap_frame(p);
result = hipe_tailcall_to_native(p, arity, reg);
@@ -292,7 +290,7 @@ Process *hipe_mode_switch(Process *p, unsigned cmd, Eterm reg[])
/* just like a normal call from now on */
/* p->hipe.u.ncallee set in beam_emu */
- if (p->cp == hipe_beam_pc_return) {
+ if (cp_val(p->stop[0]) == hipe_beam_pc_return) {
/* Native called BEAM, which now tailcalls native. */
hipe_pop_beam_trap_frame(p);
result = hipe_tailcall_to_native(p, arity, reg);
diff --git a/erts/emulator/test/bif_SUITE.erl b/erts/emulator/test/bif_SUITE.erl
index c5abd04e07..2a965d2095 100644
--- a/erts/emulator/test/bif_SUITE.erl
+++ b/erts/emulator/test/bif_SUITE.erl
@@ -860,6 +860,7 @@ error_stacktrace_test() ->
Types = [apply_const_last, apply_const, apply_last,
apply, double_apply_const_last, double_apply_const,
double_apply_last, double_apply, multi_apply_const_last,
+ apply_const_only, apply_only,
multi_apply_const, multi_apply_last, multi_apply,
call_const_last, call_last, call_const, call],
lists:foreach(fun (Type) ->
@@ -897,6 +898,8 @@ error_stacktrace_test() ->
ok.
stk([], Type, Func) ->
+ put(erlang, erlang),
+ put(tail, []),
tail(Type, Func, jump),
ok;
stk([_|L], Type, Func) ->
@@ -910,6 +913,12 @@ tail(Type, error_1, do) ->
tail(Type, error_2, do) ->
do_error_2(Type).
+do_error_2(apply_const_only) ->
+ apply(erlang, error, [oops, [apply_const_only]]);
+do_error_2(apply_only) ->
+ Erlang = get(erlang),
+ Tail = get(tail),
+ apply(Erlang, error, [oops, [apply_only|Tail]]);
do_error_2(apply_const_last) ->
erlang:apply(erlang, error, [oops, [apply_const_last]]);
do_error_2(apply_const) ->
@@ -951,6 +960,12 @@ do_error_2(call) ->
erlang:error(id(oops), id([call])).
+do_error_1(apply_const_only) ->
+ apply(erlang, error, [oops]);
+do_error_1(apply_only) ->
+ Erlang = get(erlang),
+ Tail = get(tail),
+ apply(Erlang, error, [oops|Tail]);
do_error_1(apply_const_last) ->
erlang:apply(erlang, error, [oops]);
do_error_1(apply_const) ->
diff --git a/erts/emulator/test/hibernate_SUITE.erl b/erts/emulator/test/hibernate_SUITE.erl
index a20f306e04..d65d0ff2fd 100644
--- a/erts/emulator/test/hibernate_SUITE.erl
+++ b/erts/emulator/test/hibernate_SUITE.erl
@@ -46,12 +46,17 @@ all() ->
basic(Config) when is_list(Config) ->
Ref = make_ref(),
Info = {self(),Ref},
- ExpectedHeapSz = erts_debug:size([Info]),
+ ExpectedHeapSz = expected_heap_size([Info]),
Child = spawn_link(fun() -> basic_hibernator(Info) end),
hibernate_wake_up(100, ExpectedHeapSz, Child),
Child ! please_quit_now,
ok.
+expected_heap_size(Term) ->
+ %% When hibernating, an extra word will be allocated on the stack
+ %% for a continuation pointer.
+ erts_debug:size(Term) + 1.
+
hibernate_wake_up(0, _, _) -> ok;
hibernate_wake_up(N, ExpectedHeapSz, Child) ->
{heap_size,Before} = process_info(Child, heap_size),
@@ -142,7 +147,7 @@ whats_up_calc(A1, A2, A3, A4, A5, A6, A7, A8, A9, Acc) ->
dynamic_call(Config) when is_list(Config) ->
Ref = make_ref(),
Info = {self(),Ref},
- ExpectedHeapSz = erts_debug:size([Info]),
+ ExpectedHeapSz = expected_heap_size([Info]),
Child = spawn_link(fun() -> ?MODULE:dynamic_call_hibernator(Info, hibernate) end),
hibernate_wake_up(100, ExpectedHeapSz, Child),
Child ! please_quit_now,
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-24 18:05:39 +0000