Optimize handling of BIF errors

8 files changed, 108 insertions, 103 deletions

diff --git a/erts/emulator/Makefile.in b/erts/emulator/Makefile.in
index eb27703d6a..18fd7f320b 100644
--- a/erts/emulator/Makefile.in
+++ b/erts/emulator/Makefile.in
@@ -589,7 +589,7 @@ $(TTF_DIR)/erl_bif_wrap.c \
 $(TTF_DIR)/erl_bif_list.h \
 $(TTF_DIR)/erl_atom_table.c \
 $(TTF_DIR)/erl_atom_table.h \
-$(TTF_DIR)/erl_gc_bifs.c \
+$(TTF_DIR)/erl_guard_bifs.c \
 $(TTF_DIR)/erl_dirty_bif_wrap.c \
 $(HIPE_NBIF_FILES) \
 	: $(TTF_DIR)/TABLES-GENERATED
@@ -775,7 +775,7 @@ RUN_OBJS = \
 	$(OBJDIR)/erl_bif_os.o		$(OBJDIR)/erl_bif_lists.o \
 	$(OBJDIR)/erl_bif_trace.o	$(OBJDIR)/erl_bif_unique.o \
 	$(OBJDIR)/erl_bif_wrap.o	$(OBJDIR)/erl_nfunc_sched.o \
-	$(OBJDIR)/erl_gc_bifs.o 	$(OBJDIR)/erl_dirty_bif_wrap.o \
+	$(OBJDIR)/erl_guard_bifs.o 	$(OBJDIR)/erl_dirty_bif_wrap.o \
 	$(OBJDIR)/erl_trace.o		$(OBJDIR)/copy.o \
 	$(OBJDIR)/utils.o		$(OBJDIR)/bif.o \
 	$(OBJDIR)/io.o 			$(OBJDIR)/erl_printf_term.o\
diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index befd2989f9..cfdf61eed0 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -1057,9 +1057,10 @@ do {                                            \
  * The following functions are called directly by process_main().
  * Don't inline them.
  */
-static BifFunction translate_gc_bif(void* gcf) NOINLINE;
+static ErtsCodeMFA *ubif2mfa(void* uf) NOINLINE;
+static ErtsCodeMFA *gcbif2mfa(void* gcf) NOINLINE;
 static BeamInstr* handle_error(Process* c_p, BeamInstr* pc,
-			       Eterm* reg, BifFunction bf) NOINLINE;
+			       Eterm* reg, ErtsCodeMFA* bif_mfa) NOINLINE;
 static BeamInstr* call_error_handler(Process* p, ErtsCodeMFA* mfa,
 				     Eterm* reg, Eterm func) NOINLINE;
 static BeamInstr* fixed_apply(Process* p, Eterm* reg, Uint arity,
@@ -1088,7 +1089,7 @@ static BeamInstr* next_catch(Process* c_p, Eterm *reg);
 static void terminate_proc(Process* c_p, Eterm Value);
 static Eterm add_stacktrace(Process* c_p, Eterm Value, Eterm exc);
 static void save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
-			     BifFunction bf, Eterm args);
+			    ErtsCodeMFA *bif_mfa, Eterm args);
 static struct StackTrace * get_trace_from_exc(Eterm exc);
 static Eterm make_arglist(Process* c_p, Eterm* reg, int a);
 
@@ -2640,7 +2641,7 @@ do {						\
 	}
 	reg[0] = tmp_reg[0];
 	SWAPOUT;
-	I = handle_error(c_p, I, reg, bf);
+	I = handle_error(c_p, I, reg, ubif2mfa((void *) bf));
 	goto post_error_handling;
     }
 
@@ -2676,7 +2677,7 @@ do {						\
 	    Goto(*I);
 	}
 	x(0) = x(live);
-	I = handle_error(c_p, I, reg, translate_gc_bif((void *) bf));
+	I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
 	goto post_error_handling;
     }
 
@@ -2721,7 +2722,7 @@ do {						\
 	live--;
 	x(0) = x(live);
 	x(1) = x(live+1);
-	I = handle_error(c_p, I, reg, translate_gc_bif((void *) bf));
+	I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
 	goto post_error_handling;
     }
 
@@ -2767,7 +2768,7 @@ do {						\
 	x(0) = x(live);
 	x(1) = x(live+1);
 	x(2) = x(live+2);
-	I = handle_error(c_p, I, reg, translate_gc_bif((void *) bf));
+	I = handle_error(c_p, I, reg, gcbif2mfa((void *) bf));
 	goto post_error_handling;
     }
 
@@ -2829,7 +2830,7 @@ do {						\
 	reg[0] = tmp_reg[0];
 	reg[1] = tmp_reg[1];
 	SWAPOUT;
-	I = handle_error(c_p, I, reg, bf);
+	I = handle_error(c_p, I, reg, ubif2mfa((void *) bf));
 	goto post_error_handling;
     }
 
@@ -2906,7 +2907,7 @@ do {						\
 	 * Error handling.  SWAPOUT is not needed because it was done above.
 	 */
 	ASSERT(c_p->stop == E);
-	I = handle_error(c_p, I, reg, bf);
+	I = handle_error(c_p, I, reg, &export->info.mfa);
 	goto post_error_handling;
     }
 
@@ -3210,7 +3211,7 @@ do {						\
 	 SET_I(next);
 	 Dispatch();
      }
-     I = handle_error(c_p, I, reg, apply_3);
+     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
      goto post_error_handling;
  }
 
@@ -3225,7 +3226,7 @@ do {						\
 	 SET_I(next);
 	 Dispatch();
      }
-     I = handle_error(c_p, I, reg, apply_3);
+     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
      goto post_error_handling;
  }
 
@@ -3238,7 +3239,7 @@ do {						\
 	 SET_I(next);
 	 Dispatch();
      }
-     I = handle_error(c_p, I, reg, apply_3);
+     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
      goto post_error_handling;
  }
 
@@ -3253,7 +3254,7 @@ do {						\
 	 SET_I(next);
 	 Dispatch();
      }
-     I = handle_error(c_p, I, reg, apply_3);
+     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
      goto post_error_handling;
  }
 
@@ -3269,7 +3270,7 @@ do {						\
 	 SET_I(next);
 	 Dispatch();
      }
-     I = handle_error(c_p, I, reg, apply_3);
+     I = handle_error(c_p, I, reg, &bif_export[BIF_apply_3]->info.mfa);
      goto post_error_handling;
  }
 
@@ -3690,7 +3691,7 @@ do {						\
 		}
 		Dispatch();
 	    }
-	    I = handle_error(c_p, c_p->cp, reg, vbf);
+	    I = handle_error(c_p, c_p->cp, reg, c_p->current);
 	    goto post_error_handling;
 	}
     }
@@ -5045,7 +5046,7 @@ do {						\
 	 goto do_schedule;
      } else {
 	 HEAVY_SWAPIN;
-	 I = handle_error(c_p, I, reg, hibernate_3);
+	 I = handle_error(c_p, I, reg, &bif_export[BIF_hibernate_3]->info.mfa);
 	 goto post_error_handling;
      }
  }
@@ -5437,17 +5438,28 @@ void erts_dirty_process_main(ErtsSchedulerData *esdp)
 #endif /* ERTS_DIRTY_SCHEDULERS */
 }
 
-static BifFunction
-translate_gc_bif(void* gcf)
+static ErtsCodeMFA *
+gcbif2mfa(void* gcf)
 {
-    const ErtsGcBif* p;
-
-    for (p = erts_gc_bifs; p->bif != 0; p++) {
-	if (p->gc_bif == gcf) {
-	    return p->bif;
-	}
+    int i;
+    for (i = 0; erts_gc_bifs[i].bif; i++) {
+	if (erts_gc_bifs[i].gc_bif == gcf)
+	    return &bif_export[erts_gc_bifs[i].exp_ix]->info.mfa;
     }
     erts_exit(ERTS_ERROR_EXIT, "bad gc bif");
+    return NULL;
+}
+
+static ErtsCodeMFA *
+ubif2mfa(void* uf)
+{
+    int i;
+    for (i = 0; erts_u_bifs[i].bif; i++) {
+	if (erts_u_bifs[i].bif == uf)
+	    return &bif_export[erts_u_bifs[i].exp_ix]->info.mfa;
+    }
+    erts_exit(ERTS_ERROR_EXIT, "bad u bif");
+    return NULL;
 }
 
 /*
@@ -5506,7 +5518,7 @@ Eterm error_atom[NUMBER_EXIT_CODES] = {
  */
 
 static BeamInstr*
-handle_error(Process* c_p, BeamInstr* pc, Eterm* reg, BifFunction bf)
+handle_error(Process* c_p, BeamInstr* pc, Eterm* reg, ErtsCodeMFA *bif_mfa)
 {
     Eterm* hp;
     Eterm Value = c_p->fvalue;
@@ -5514,9 +5526,16 @@ handle_error(Process* c_p, BeamInstr* pc, Eterm* reg, BifFunction bf)
 
     ASSERT(c_p->freason != TRAP); /* Should have been handled earlier. */
 
-    if (c_p->freason & EXF_RESTORE_NIF) {
-	erts_nif_export_restore_error(c_p, &pc, reg, &bf);
+    if (c_p->freason & EXF_RESTORE_NIF)
+	erts_nif_export_restore_error(c_p, &pc, reg, &bif_mfa);
+
+#ifdef DEBUG
+    if (bif_mfa) {
+	/* Verify that bif_mfa does not point into our nif export */
+	NifExport *nep = ERTS_PROC_GET_NIF_TRAP_EXPORT(c_p);
+	ASSERT(!nep || !ErtsInArea(bif_mfa, (char *)nep, sizeof(NifExport)));
     }
+#endif
 
     c_p->i = pc;    /* In case we call erts_exit(). */
 
@@ -5542,7 +5561,7 @@ handle_error(Process* c_p, BeamInstr* pc, Eterm* reg, BifFunction bf)
      * more modular.
      */
     if (c_p->freason & EXF_SAVETRACE) {
-        save_stacktrace(c_p, pc, reg, bf, Args);
+        save_stacktrace(c_p, pc, reg, bif_mfa, Args);
     }
 
     /*
@@ -5817,23 +5836,12 @@ expand_error_value(Process* c_p, Uint freason, Eterm Value) {
  */
 
 static void
-save_stacktrace_current(struct StackTrace *s, Process *c_p, ErtsCodeMFA *mfa)
-{
-    NifExport *nep = (NifExport *) ERTS_PROC_GET_NIF_TRAP_EXPORT(c_p);
-    if (!nep || &nep->exp.info.mfa != mfa)
-	s->current = mfa;
-    else {
-	s->mfa = *mfa;
-	s->current = &s->mfa;
-    }
-}
-
-static void
-save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg, BifFunction bf,
-		Eterm args) {
+save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg,
+		ErtsCodeMFA *bif_mfa, Eterm args) {
     struct StackTrace* s;
     int sz;
     int depth = erts_backtrace_depth;    /* max depth (never negative) */
+
     if (depth > 0) {
 	/* There will always be a current function */
 	depth --;
@@ -5850,33 +5858,29 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg, BifFunction bf,
 
     /*
      * If the failure was in a BIF other than 'error/1', 'error/2',
-     * 'exit/1' or 'throw/1', find the bif-table index and save the
-     * argument registers by consing up an arglist.
+     * 'exit/1' or 'throw/1', save BIF-MFA and save the argument
+     * registers by consing up an arglist.
      */
-    if (bf != NULL && bf != error_1 && bf != error_2 && bf != exit_1
-	&& bf != throw_1 && bf != wrap_error_1 && bf != wrap_error_2
-	&& bf != wrap_exit_1 && bf != wrap_throw_1) {
-        int i;
-	int a;
-	for (i = 0; i < BIF_SIZE; i++) {
-	    if (bf == bif_table[i].f || bf == bif_table[i].traced) {
-		save_stacktrace_current(s, c_p, &bif_export[i]->info.mfa);
+    if (bif_mfa) {
+	if (bif_mfa->module == am_erlang) {
+	    switch (bif_mfa->function) {
+	    case am_error:
+		if (bif_mfa->arity == 1 || bif_mfa->arity == 2)
+		    goto non_bif_stacktrace;
+		break;
+	    case am_exit:
+		if (bif_mfa->arity == 1)
+		    goto non_bif_stacktrace;
+		break;
+	    case am_throw:
+		if (bif_mfa->arity == 1)
+		    goto non_bif_stacktrace;
+		break;
+	    default:
 		break;
 	    }
 	}
-	if (i >= BIF_SIZE) {
-	    /* 
-	     * The Bif does not really exist (no BIF entry).  It is a
-	     * TRAP and traps are called through apply_bif, which also
-	     * sets c_p->current (luckily).
-	     * OR it is a NIF called by call_nif where current is also set.
-	     */
-	    ASSERT(c_p->current);
-	    save_stacktrace_current(s, c_p, c_p->current);
-	}
-
-	a = s->current->arity;
-
+	s->current = bif_mfa;
 	/* Save first stack entry */
 	ASSERT(pc);
 	if (depth > 0) {
@@ -5889,11 +5893,12 @@ save_stacktrace(Process* c_p, BeamInstr* pc, Eterm* reg, BifFunction bf,
 	    depth--;
 	}
 	s->pc = NULL;
-	args = make_arglist(c_p, reg, a); /* Overwrite CAR(c_p->ftrace) */
+	args = make_arglist(c_p, reg, bif_mfa->arity); /* Overwrite CAR(c_p->ftrace) */
     } else {
 
-	save_stacktrace_current(s, c_p, c_p->current);
+    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.
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index 7bcb7c196d..5f0564474f 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -5027,17 +5027,16 @@ void erts_init_bif(void)
 
 #define ERTS_SCHED_BIF_TRAP_MARKER ((void *) (UWord) 1)
 
-static void
+static ERTS_INLINE void
 schedule(Process *c_p, Process *dirty_shadow_proc,
-	 ErtsCodeMFA *mfa, BifFunction *nif, BeamInstr *pc,
+	 ErtsCodeMFA *mfa, BeamInstr *pc,
 	 ErtsBifFunc dfunc, void *ifunc,
 	 Eterm module, Eterm function,
 	 int argc, Eterm *argv)
 {
     ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
     (void) erts_nif_export_schedule(c_p, dirty_shadow_proc,
-				    mfa, nif, pc,
-				    (BeamInstr) em_apply_bif,
+				    mfa, pc, (BeamInstr) em_apply_bif,
 				    dfunc, ifunc,
 				    module, function,
 				    argc, argv);
@@ -5120,11 +5119,10 @@ erts_schedule_bif(Process *proc,
 
     if (!ERTS_PROC_IS_EXITING(c_p)) {
 	Export *exp;
-	BifFunction obif, dbif, ibif;
+	BifFunction dbif, ibif;
 	BeamInstr *pc;
 
 	/*
-	 * obif - original bif
 	 * dbif - direct bif
 	 * ibif - indirect bif
 	 */
@@ -5160,14 +5158,12 @@ erts_schedule_bif(Process *proc,
 
 	if (i == NULL) {
 	    ERTS_INTERNAL_ERROR("Missing instruction pointer");
-	    obif = NULL;
 	}
 #ifdef HIPE
 	else if (proc->flags & F_HIPE_MODE) {
 	    /* Pointer to bif export in i */
 	    exp = (Export *) i;
 	    pc = c_p->cp;
-	    obif = (BifFunction) exp->beam[1];
 	    mfa = &exp->info.mfa;
 	}
 #endif
@@ -5175,19 +5171,16 @@ erts_schedule_bif(Process *proc,
 	    /* Pointer to bif export in i+1 */
 	    exp = (Export *) i[1];
 	    pc = i;
-	    obif = (BifFunction) exp->beam[1];
 	    mfa = &exp->info.mfa;
 	}
 	else if (em_apply_bif == (BeamInstr *) *i) {
 	    /* Pointer to bif in i+1, and mfa in i-3 */	    
-	    obif = (BifFunction) i[1];
 	    pc = c_p->cp;
 	    mfa = erts_code_to_codemfa(i);
 	}
 	else {
 	    ERTS_INTERNAL_ERROR("erts_schedule_bif() called "
 				"from unexpected instruction");
-	    obif = NULL;
 	}
 	ASSERT(bif);
 
@@ -5197,8 +5190,8 @@ erts_schedule_bif(Process *proc,
 	    argc = (int) mfa->arity;
 	}
 
-	schedule(c_p, dirty_shadow_proc, mfa, obif,
-		 pc, dbif, ibif, mod, func, argc, argv);
+	schedule(c_p, dirty_shadow_proc, mfa, pc, dbif, ibif,
+		 mod, func, argc, argv);
     }
 
     if (dirty_shadow_proc)
@@ -5295,14 +5288,14 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
 
     if (!exiting) {
 	if (is_value(result))
-	    schedule(c_p, dirty_shadow_proc, NULL, NULL, NULL, dirty_bif_result,
+	    schedule(c_p, dirty_shadow_proc, NULL, NULL, dirty_bif_result,
 		     NULL, am_erts_internal, am_dirty_bif_result, 1, &result);
 	else if (dirty_shadow_proc->freason != TRAP) {
 	    Eterm argv[2];
 	    ASSERT(dirty_shadow_proc->freason <= MAX_SMALL);
 	    argv[0] = make_small(dirty_shadow_proc->freason);
 	    argv[1] = dirty_shadow_proc->fvalue;
-	    schedule(c_p, dirty_shadow_proc, NULL, NULL, NULL,
+	    schedule(c_p, dirty_shadow_proc, NULL, NULL,
 		     dirty_bif_exception, NULL, am_erts_internal,
 		     am_dirty_bif_exception, 2, argv);
 	}
@@ -5310,7 +5303,7 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
 	    /* Dirty BIF did an ordinary trap... */
 	    ASSERT(!(erts_smp_atomic32_read_nob(&c_p->state)
 		     & (ERTS_PSFLG_DIRTY_CPU_PROC|ERTS_PSFLG_DIRTY_IO_PROC)));
-	    schedule(c_p, dirty_shadow_proc, NULL, NULL, NULL,
+	    schedule(c_p, dirty_shadow_proc, NULL, NULL,
 		     dirty_bif_trap, (void *) dirty_shadow_proc->i,
 		     am_erts_internal, am_dirty_bif_trap,
 		     dirty_shadow_proc->arity, reg);
diff --git a/erts/emulator/beam/erl_nfunc_sched.c b/erts/emulator/beam/erl_nfunc_sched.c
index 0333545255..bc3fd83d7a 100644
--- a/erts/emulator/beam/erl_nfunc_sched.c
+++ b/erts/emulator/beam/erl_nfunc_sched.c
@@ -63,7 +63,7 @@ erts_destroy_nif_export(Process *p)
 
 NifExport *
 erts_nif_export_schedule(Process *c_p, Process *dirty_shadow_proc,
-			 ErtsCodeMFA *mfa, void *nif, BeamInstr *pc,
+			 ErtsCodeMFA *mfa, BeamInstr *pc,
 			 BeamInstr instr,
 			 void *dfunc, void *ifunc,
 			 Eterm mod, Eterm func,
@@ -111,8 +111,6 @@ erts_nif_export_schedule(Process *c_p, Process *dirty_shadow_proc,
 	    nep->argv[i] = reg[i];
 	nep->pc = pc;
 	nep->cp = c_p->cp;
-	ASSERT(nif);
-	nep->nif = nif;
 	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 72de7f0eb5..d7eccb28ba 100644
--- a/erts/emulator/beam/erl_nfunc_sched.h
+++ b/erts/emulator/beam/erl_nfunc_sched.h
@@ -52,7 +52,7 @@ typedef struct {
 NifExport *erts_new_proc_nif_export(Process *c_p, int argc);
 void erts_destroy_nif_export(Process *p);
 NifExport *erts_nif_export_schedule(Process *c_p, Process *dirty_shadow_proc,
-				    ErtsCodeMFA *mfa, void *nif, BeamInstr *pc,
+				    ErtsCodeMFA *mfa, BeamInstr *pc,
 				    BeamInstr instr,
 				    void *dfunc, void *ifunc,
 				    Eterm mod, Eterm func,
@@ -65,7 +65,7 @@ ERTS_GLB_INLINE int erts_check_nif_export_in_area(Process *p,
 						  char *start, Uint size);
 ERTS_GLB_INLINE void erts_nif_export_restore(Process *c_p, NifExport *ep);
 ERTS_GLB_INLINE void erts_nif_export_restore_error(Process* c_p, BeamInstr **pc,
-						   Eterm *reg, void **nif);
+						   Eterm *reg, ErtsCodeMFA **nif_mfa);
 ERTS_GLB_INLINE Process *erts_proc_shadow2real(Process *c_p);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
@@ -132,8 +132,8 @@ erts_nif_export_restore(Process *c_p, NifExport *ep)
 }
 
 ERTS_GLB_INLINE void
-erts_nif_export_restore_error(Process* c_p, BeamInstr **pc, Eterm *reg,
-			      void **nif)
+erts_nif_export_restore_error(Process* c_p, BeamInstr **pc,
+			      Eterm *reg, ErtsCodeMFA **nif_mfa)
 {
     NifExport *nep = (NifExport *) ERTS_PROC_GET_NIF_TRAP_EXPORT(c_p);
     int ix;
@@ -141,7 +141,7 @@ erts_nif_export_restore_error(Process* c_p, BeamInstr **pc, Eterm *reg,
     ASSERT(nep);
     *pc = nep->pc;
     c_p->cp = nep->cp;
-    *nif = nep->nif;
+    *nif_mfa = nep->mfa;
     for (ix = 0; ix < nep->argc; ix++)
 	reg[ix] = nep->argv[ix];
     erts_nif_export_restore(c_p, nep);
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index ee4b22f7ca..fd756692f9 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -266,7 +266,6 @@ static ERTS_INLINE ERL_NIF_TERM
 schedule(ErlNifEnv* env, NativeFunPtr direct_fp, NativeFunPtr indirect_fp,
 	 Eterm mod, Eterm func_name, int argc, const ERL_NIF_TERM argv[])
 {
-    Export *exp;
     NifExport *ep;
     Process *c_p, *dirty_shadow_proc;
 
@@ -278,11 +277,8 @@ schedule(ErlNifEnv* env, NativeFunPtr direct_fp, NativeFunPtr indirect_fp,
 
     ERTS_SMP_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(c_p));
 
-    exp = ErtsContainerStruct(c_p->current, Export, info.mfa);
-
     ep = erts_nif_export_schedule(c_p, dirty_shadow_proc,
 				  c_p->current,
-				  (BifFunction) exp->beam[1],
 				  c_p->cp,
 				  (BeamInstr) em_call_nif,
 				  direct_fp, indirect_fp,
diff --git a/erts/emulator/beam/error.h b/erts/emulator/beam/error.h
index 99a8ff6bad..64c08b1570 100644
--- a/erts/emulator/beam/error.h
+++ b/erts/emulator/beam/error.h
@@ -214,7 +214,6 @@ struct StackTrace {
     BeamInstr* pc;
     ErtsCodeMFA* current;
     int depth;	/* number of saved pointers in trace[] */
-    ErtsCodeMFA mfa; /* in case we need to make a copy of mfa */
     BeamInstr *trace[1];  /* varying size - must be last in struct */
 };
 
diff --git a/erts/emulator/utils/make_tables b/erts/emulator/utils/make_tables
index 1d3023ee9a..47e1528958 100755
--- a/erts/emulator/utils/make_tables
+++ b/erts/emulator/utils/make_tables
@@ -37,6 +37,7 @@ use File::Basename;
 #    <-src>/erl_bif_table.c
 #    <-src>/erl_bif_wrap.c
 #    <-src>/erl_dirty_bif_wrap.c
+#    <-src>/erl_guard_bifs.c
 #    <-src>/hipe_nbif_impl.c
 #    <-include>/hipe_nbif_impl.h
 #    <-include>/erl_atom_table.h
@@ -228,11 +229,18 @@ typedef struct bif_entry {
 typedef struct erts_gc_bif {
     BifFunction bif;
     BifFunction gc_bif;
+    int exp_ix;
 } ErtsGcBif;
 
+typedef struct erts_u_bif {
+    BifFunction bif;
+    int exp_ix;
+} ErtsUBif;
+
 extern BifEntry bif_table[];
 extern Export* bif_export[];
 extern const ErtsGcBif erts_gc_bifs[];
+extern const ErtsUBif erts_u_bifs[];
 
 #define BIF_SIZE $bif_size
 
@@ -304,18 +312,24 @@ for ($i = 0; $i < @bif; $i++) {
 # Generate erl_gc_bifs.c.
 #
 
-open_file("$src/erl_gc_bifs.c");
+open_file("$src/erl_guard_bifs.c");
 my $i;
 includes("export.h", "sys.h", "erl_vm.h", "global.h", "erl_process.h", "bif.h",
 	 "erl_bif_table.h");
 print "const ErtsGcBif erts_gc_bifs[] = {\n";
 for ($i = 0; $i < @bif; $i++) {
     next unless $bif_info[$i]->[0] eq 'gcbif';
-    my $arity = $bif[$i]->[2];
-    my $func = $bif[$i]->[3];
-    print "  {$func, erts_gc_$func},\n";
+    print "  {$bif[$i]->[3], erts_gc_$bif[$i]->[3], BIF_$bif[$i]->[5]},\n";
+}
+print "  {NULL, NULL, -1}\n";
+print "};\n";
+
+print "const ErtsUBif erts_u_bifs[] = {\n";
+for ($i = 0; $i < @bif; $i++) {
+    next unless $bif_info[$i]->[0] eq 'ubif';
+    print "  {$bif[$i]->[3], BIF_$bif[$i]->[5]},\n";
 }
-print "  {0, 0}\n";
+print "  {NULL, -1}\n";
 print "};\n";
 
 #