19 files changed, 484 insertions, 336 deletions

diff --git a/erts/emulator/beam/atom.names b/erts/emulator/beam/atom.names
index a14f22b19e..291bc95604 100644
--- a/erts/emulator/beam/atom.names
+++ b/erts/emulator/beam/atom.names
@@ -546,6 +546,7 @@ atom reload
 atom rem
 atom report_errors
 atom reset
+atom reset_seq_trace
 atom restart
 atom return_from
 atom return_to
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index 015c051cc1..000397e790 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -2810,38 +2810,110 @@ BIF_RETTYPE list_to_existing_atom_1(BIF_ALIST_1)
 
 /* convert an integer to a list of ascii integers */
 
-BIF_RETTYPE integer_to_list_1(BIF_ALIST_1)
+static Eterm integer_to_list(Process *c_p, Eterm num, int base)
 {
-    Eterm* hp;
+    Eterm *hp;
+    Eterm res;
     Uint need;
 
+    if (is_small(num)) {
+        char s[128];
+        char *c = s;
+        Uint digits;
+
+        digits = Sint_to_buf(signed_val(num), base, &c, sizeof(s));
+        need = 2 * digits;
+
+        hp = HAlloc(c_p, need);
+        res = buf_to_intlist(&hp, c, digits, NIL);
+    } else {
+        const int DIGITS_PER_RED = 16;
+        Eterm *hp_end;
+        Uint digits;
+
+        digits = big_integer_estimate(num, base);
+
+        if ((digits / DIGITS_PER_RED) > ERTS_BIF_REDS_LEFT(c_p)) {
+            ErtsSchedulerData *esdp = erts_get_scheduler_data();
+
+            /* This could take a very long time, tell the caller to reschedule
+             * us to a dirty CPU scheduler if we aren't already on one. */
+            if (esdp->type == ERTS_SCHED_NORMAL) {
+                return THE_NON_VALUE;
+            }
+        } else {
+            BUMP_REDS(c_p, digits / DIGITS_PER_RED);
+        }
+
+        need = 2 * digits;
+
+        hp = HAlloc(c_p, need);
+        hp_end = hp + need;
+
+        res = erts_big_to_list(num, base, &hp);
+        HRelease(c_p, hp_end, hp);
+    }
+
+    return res;
+}
+
+BIF_RETTYPE integer_to_list_1(BIF_ALIST_1)
+{
+    Eterm res;
+
     if (is_not_integer(BIF_ARG_1)) {
-	BIF_ERROR(BIF_P, BADARG);
+        BIF_ERROR(BIF_P, BADARG);
     }
 
-    if (is_small(BIF_ARG_1)) {
-	char *c;
-	int n;
-	struct Sint_buf ibuf;
+    res = integer_to_list(BIF_P, BIF_ARG_1, 10);
 
-	c = Sint_to_buf(signed_val(BIF_ARG_1), &ibuf);
-	n = sys_strlen(c);
-	need = 2*n;
-	hp = HAlloc(BIF_P, need);
-	BIF_RET(buf_to_intlist(&hp, c, n, NIL));
+    if (is_non_value(res)) {
+        Eterm args[1];
+        args[0] = BIF_ARG_1;
+        return erts_schedule_bif(BIF_P,
+                                 args,
+                                 BIF_I,
+                                 integer_to_list_1,
+                                 ERTS_SCHED_DIRTY_CPU,
+                                 am_erlang,
+                                 am_integer_to_list,
+                                 1);
     }
-    else {
-	int n = big_decimal_estimate(BIF_ARG_1);
-	Eterm res;
-        Eterm* hp_end;
 
-	need = 2*n;
-	hp = HAlloc(BIF_P, need);
-        hp_end = hp + need;
-	res = erts_big_to_list(BIF_ARG_1, &hp);
-        HRelease(BIF_P,hp_end,hp);
-	BIF_RET(res);
+    return res;
+}
+
+BIF_RETTYPE integer_to_list_2(BIF_ALIST_2)
+{
+    Eterm res;
+    SWord base;
+
+    if (is_not_integer(BIF_ARG_1) || is_not_small(BIF_ARG_2)) {
+        BIF_ERROR(BIF_P, BADARG);
     }
+
+    base = signed_val(BIF_ARG_2);
+    if (base < 2 || base > 36) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+
+    res = integer_to_list(BIF_P, BIF_ARG_1, base);
+
+    if (is_non_value(res)) {
+        Eterm args[2];
+        args[0] = BIF_ARG_1;
+        args[1] = BIF_ARG_2;
+        return erts_schedule_bif(BIF_P,
+                                 args,
+                                 BIF_I,
+                                 integer_to_list_2,
+                                 ERTS_SCHED_DIRTY_CPU,
+                                 am_erlang,
+                                 am_integer_to_list,
+                                 2);
+    }
+
+    return res;
 }
 
 /**********************************************************************/
@@ -4490,11 +4562,12 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
         ERTS_TRACER_CLEAR(&old_seq_tracer);
 
         BIF_RET(ret);
-    } else if (BIF_ARG_1 == make_small(1)) {
+    } else if (BIF_ARG_1 == am_reset_seq_trace) {
 	int i, max;
-	erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
-	erts_thr_progress_block();
 
+        erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
+        erts_thr_progress_block();
+        
 	max = erts_ptab_max(&erts_proc);
 	for (i = 0; i < max; i++) {
 	    Process *p = erts_pix2proc(i);
@@ -4506,13 +4579,14 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 #endif
 		p->seq_trace_clock = 0;
 		p->seq_trace_lastcnt = 0;
-
+                erts_proc_lock(p, ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_MSGQ);
                 erts_proc_sig_clear_seq_trace_tokens(p);
+                erts_proc_unlock(p, ERTS_PROC_LOCK_MAIN|ERTS_PROC_LOCK_MSGQ);
 	    }
 	}
 
-	erts_thr_progress_unblock();
-	erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
+        erts_thr_progress_unblock();
+        erts_proc_lock(BIF_P, ERTS_PROC_LOCK_MAIN);
 
 	BIF_RET(am_true);
     } else if (BIF_ARG_1 == am_scheduler_wall_time) {
@@ -4627,6 +4701,9 @@ BIF_RETTYPE system_flag_2(BIF_ALIST_2)
 	return erts_bind_schedulers(BIF_P, BIF_ARG_2);
     } else if (ERTS_IS_ATOM_STR("erts_alloc", BIF_ARG_1)) {
         return erts_alloc_set_dyn_param(BIF_P, BIF_ARG_2);
+    } else if (ERTS_IS_ATOM_STR("system_logger", BIF_ARG_1)) {
+        Eterm res = erts_set_system_logger(BIF_ARG_2);
+        if (is_value(res)) BIF_RET(res);
     }
     error:
     BIF_ERROR(BIF_P, BADARG);
@@ -5129,61 +5206,6 @@ erts_call_dirty_bif(ErtsSchedulerData *esdp, Process *c_p, BeamInstr *I, Eterm *
     return exiting;
 }
 
-
-
-#ifdef HARDDEBUG
-/*
-You'll need this line in bif.tab to be able to use this debug bif
-
-bif erlang:send_to_logger/2
-
-*/
-BIF_RETTYPE send_to_logger_2(BIF_ALIST_2)
-{
-    byte *buf;
-    ErlDrvSizeT len;
-    if (!is_atom(BIF_ARG_1) || !(is_list(BIF_ARG_2) ||
-				 is_nil(BIF_ARG_1))) {
-	BIF_ERROR(BIF_P,BADARG);
-    }
-    if (erts_iolist_size(BIF_ARG_2, &len) != 0)
-	BIF_ERROR(BIF_P,BADARG);
-    else if (len == 0)
-	buf = "";
-    else {
-#ifdef DEBUG
-	ErlDrvSizeT len2;
-#endif
-	buf = (byte *) erts_alloc(ERTS_ALC_T_TMP, len+1);
-#ifdef DEBUG
-	len2 =
-#else
-	(void)
-#endif
-	    erts_iolist_to_buf(BIF_ARG_2, buf, len);
-	ASSERT(len2 == len);
-	buf[len] = '\0';
-	switch (BIF_ARG_1) {
-	case am_info:
-	    erts_send_info_to_logger(BIF_P->group_leader, buf, len);
-	    break;
-	case am_warning:
-	    erts_send_warning_to_logger(BIF_P->group_leader, buf, len);
-	    break;
-	case am_error:
-	    erts_send_error_to_logger(BIF_P->group_leader, buf, len);
-	    break;
-	default:
-	{
-	    BIF_ERROR(BIF_P,BADARG);
-	}
-	}
-	erts_free(ERTS_ALC_T_TMP, (void *) buf);
-    }
-    BIF_RET(am_true);
-}
-#endif /* HARDDEBUG */
-
 BIF_RETTYPE get_module_info_1(BIF_ALIST_1)
 {
     Eterm ret = erts_module_info_0(BIF_P, BIF_ARG_1);
diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab
index d4ba90a61a..c96278b10c 100644
--- a/erts/emulator/beam/bif.tab
+++ b/erts/emulator/beam/bif.tab
@@ -725,3 +725,16 @@ bif erts_internal:counters_get/2
 bif erts_internal:counters_add/3
 bif erts_internal:counters_put/3
 bif erts_internal:counters_info/1
+
+#
+# New in 21.2.3
+#
+
+bif erts_internal:spawn_system_process/3
+
+#
+# New in 21.3
+#
+
+bif erlang:integer_to_list/2
+bif erlang:integer_to_binary/2
diff --git a/erts/emulator/beam/big.c b/erts/emulator/beam/big.c
index b373d3a577..522f50287a 100644
--- a/erts/emulator/beam/big.c
+++ b/erts/emulator/beam/big.c
@@ -429,6 +429,7 @@
 static const byte digits_per_sint_lookup[36-1];
 static const byte digits_per_small_lookup[36-1];
 static const Sint largest_power_of_base_lookup[36-1];
+static const double lg2_lookup[36-1];
 
 static ERTS_INLINE byte get_digits_per_signed_int(Uint base) {
     return digits_per_sint_lookup[base-2];
@@ -442,6 +443,10 @@ static ERTS_INLINE Sint get_largest_power_of_base(Uint base) {
     return largest_power_of_base_lookup[base-2];
 }
 
+static ERTS_INLINE double lookup_log2(Uint base) {
+    return lg2_lookup[base - 2];
+}
+
 /*
 ** compare two number vectors
 */
@@ -668,27 +673,25 @@ static dsize_t I_mul(ErtsDigit* x, dsize_t xl, ErtsDigit* y, dsize_t yl, ErtsDig
 
 static dsize_t I_sqr(ErtsDigit* x, dsize_t xl, ErtsDigit* r)
 {
-    ErtsDigit d_next = *x;
     ErtsDigit d;
     ErtsDigit* r0 = r;
     ErtsDigit* s = r;
 
     if ((r + xl) == x)	/* "Inline" operation */
 	*x = 0;
-    x++;
 	
     while(xl--) {
-	ErtsDigit* y = x;
+	ErtsDigit* y;
 	ErtsDigit y_0 = 0, y_1 = 0, y_2 = 0, y_3 = 0;
 	ErtsDigit b0, b1;
 	ErtsDigit z0, z1, z2;
 	ErtsDigit t;
 	dsize_t y_l = xl;
-		
+
+        d = *x;
+        x++;
+        y = x;
 	s = r;
-	d = d_next;
-	d_next = *x; 
-	x++;
 
 	DMUL(d, d, b1, b0);
 	DSUMc(*s, b0, y_3, t);
@@ -1722,23 +1725,23 @@ double_to_big(double x, Eterm *heap, Uint hsz)
 
 
 /*
- ** Estimate the number of decimal digits (include sign)
+ ** Estimate the number of digits in given base (include sign)
  */
-int big_decimal_estimate(Wterm x)
+int big_integer_estimate(Wterm x, Uint base)
 {
     Eterm* xp = big_val(x);
     int lg = I_lg(BIG_V(xp), BIG_SIZE(xp));
-    int lg10 = ((lg+1)*28/93)+1;
+    int lgBase = ((lg + 1) / lookup_log2(base)) + 1;
 
-    if (BIG_SIGN(xp)) lg10++;	/* add sign */
-    return lg10+1;		/* add null */
+    if (BIG_SIGN(xp)) lgBase++;	/* add sign */
+    return lgBase + 1;		/* add null */
 }
 
 /*
-** Convert a bignum into a string of decimal numbers
+** Convert a bignum into a string of numbers in given base
 */
-
-static Uint write_big(Wterm x, void (*write_func)(void *, char), void *arg)
+static Uint write_big(Wterm x, int base, void (*write_func)(void *, char),
+                      void *arg)
 {
     Eterm* xp = big_val(x);
     ErtsDigit* dx = BIG_V(xp);
@@ -1746,48 +1749,72 @@ static Uint write_big(Wterm x, void (*write_func)(void *, char), void *arg)
     short sign = BIG_SIGN(xp);
     ErtsDigit rem;
     Uint n = 0;
-    const Uint digits_per_Sint = get_digits_per_signed_int(10);
-    const Sint largest_pow_of_base = get_largest_power_of_base(10);
+    const Uint digits_per_Sint = get_digits_per_signed_int(base);
+    const Sint largest_pow_of_base = get_largest_power_of_base(base);
 
     if (xl == 1 && *dx < largest_pow_of_base) {
-	rem = *dx;
-	if (rem == 0) {
-	    (*write_func)(arg, '0'); n++;
-	} else {
-	    while(rem) {
-		(*write_func)(arg, (rem % 10) + '0'); n++;
-		rem /= 10;
-	    }
-	}
+        rem = *dx;
+        if (rem == 0) {
+            (*write_func)(arg, '0'); n++;
+        } else {
+            while(rem) {
+                int digit = rem % base;
+
+                if (digit < 10) {
+                    (*write_func)(arg, digit + '0'); n++;
+                } else {
+                    (*write_func)(arg, 'A' + (digit - 10)); n++;
+                }
+
+                rem /= base;
+            }
+        }
     } else {
-	ErtsDigit* tmp  = (ErtsDigit*) erts_alloc(ERTS_ALC_T_TMP,
-					      sizeof(ErtsDigit)*xl);
-	dsize_t tmpl = xl;
+        ErtsDigit* tmp = (ErtsDigit*) erts_alloc(ERTS_ALC_T_TMP,
+                                                 sizeof(ErtsDigit) * xl);
+        dsize_t tmpl = xl;
 
-	MOVE_DIGITS(tmp, dx, xl);
+        MOVE_DIGITS(tmp, dx, xl);
 
-	while(1) {
+        while(1) {
             tmpl = D_div(tmp, tmpl, largest_pow_of_base, tmp, &rem);
-	    if (tmpl == 1 && *tmp == 0) {
-		while(rem) {
-		    (*write_func)(arg, (rem % 10)+'0'); n++;
-		    rem /= 10;
-		}
-		break;
-	    } else {
+
+            if (tmpl == 1 && *tmp == 0) {
+                while(rem) {
+                    int digit = rem % base;
+
+                    if (digit < 10) {
+                        (*write_func)(arg, digit + '0'); n++;
+                    } else {
+                        (*write_func)(arg, 'A' + (digit - 10)); n++;
+                    }
+
+                    rem /= base;
+                }
+                break;
+            } else {
                 Uint i = digits_per_Sint;
-		while(i--) {
-		    (*write_func)(arg, (rem % 10)+'0'); n++;
-		    rem /= 10;
-		}
-	    }
-	}
-	erts_free(ERTS_ALC_T_TMP, (void *) tmp);
+
+                while(i--) {
+                    int digit = rem % base;
+
+                    if (digit < 10) {
+                        (*write_func)(arg, digit + '0'); n++;
+                    } else {
+                        (*write_func)(arg, 'A' + (digit - 10)); n++;
+                    }
+
+                    rem /= base;
+                }
+            }
+        }
+        erts_free(ERTS_ALC_T_TMP, (void *) tmp);
     }
 
     if (sign) {
-	(*write_func)(arg, '-'); n++;
+        (*write_func)(arg, '-'); n++;
     }
+
     return n;
 }
 
@@ -1804,12 +1831,12 @@ write_list(void *arg, char c)
     blp->hp += 2;
 }
 
-Eterm erts_big_to_list(Eterm x, Eterm **hpp)
+Eterm erts_big_to_list(Eterm x, int base, Eterm **hpp)
 {
     struct big_list__ bl;
     bl.hp = *hpp;
     bl.res = NIL;
-    write_big(x, write_list, (void *) &bl);
+    write_big(x, base, write_list, (void *) &bl);
     *hpp = bl.hp;
     return bl.res;
 }
@@ -1820,11 +1847,11 @@ write_string(void *arg, char c)
     *(--(*((char **) arg))) = c;
 }
 
-char *erts_big_to_string(Wterm x, char *buf, Uint buf_sz)
+char *erts_big_to_string(Wterm x, int base, char *buf, Uint buf_sz)
 {
     char *big_str = buf + buf_sz - 1;
     *big_str = '\0';
-    write_big(x, write_string, (void *) &big_str);
+    write_big(x, base, write_string, (void*)&big_str);
     ASSERT(buf <= big_str && big_str <= buf + buf_sz - 1);
     return big_str;
 }
@@ -1833,11 +1860,11 @@ char *erts_big_to_string(Wterm x, char *buf, Uint buf_sz)
  * e.g. 1 bsl 64 -> "18446744073709551616"
  */
 
-Uint erts_big_to_binary_bytes(Eterm x, char *buf, Uint buf_sz)
+Uint erts_big_to_binary_bytes(Eterm x, int base, char *buf, Uint buf_sz)
 {
     char *big_str = buf + buf_sz;
     Uint n;
-    n = write_big(x, write_string, (void *) &big_str);
+    n = write_big(x, base, write_string, (void *) &big_str);
     ASSERT(buf <= big_str && big_str <= buf + buf_sz);
     return n;
 }
@@ -2580,9 +2607,6 @@ static const double lg2_lookup[36-1] = {
     4.32193, 4.39232, 4.45943, 4.52356, 4.58496, 4.64386, 4.70044, 4.75489,
     4.80735, 4.85798, 4.90689, 4.9542, 5.0, 5.04439, 5.08746, 5.12928, 5.16993
 };
-static ERTS_INLINE double lookup_log2(Uint base) {
-    return lg2_lookup[base - 2];
-}
 
 /*
  * How many digits can fit into a signed int (Sint) for given base, we take
diff --git a/erts/emulator/beam/big.h b/erts/emulator/beam/big.h
index 7556205063..6e6d7b5a4b 100644
--- a/erts/emulator/beam/big.h
+++ b/erts/emulator/beam/big.h
@@ -119,10 +119,10 @@ typedef Uint  dsize_t;	 /* Vector size type */
 
 #endif
 
-int big_decimal_estimate(Wterm);
-Eterm erts_big_to_list(Eterm, Eterm**);
-char *erts_big_to_string(Wterm x, char *buf, Uint buf_sz);
-Uint erts_big_to_binary_bytes(Eterm x, char *buf, Uint buf_sz);
+int big_integer_estimate(Wterm, Uint base);
+Eterm erts_big_to_list(Eterm, int base, Eterm**);
+char *erts_big_to_string(Wterm x, int base, char *buf, Uint buf_sz);
+Uint erts_big_to_binary_bytes(Eterm x, int base, char *buf, Uint buf_sz);
 
 Eterm small_times(Sint, Sint, Eterm*);
 
diff --git a/erts/emulator/beam/binary.c b/erts/emulator/beam/binary.c
index 6a349764b2..a18228b84a 100644
--- a/erts/emulator/beam/binary.c
+++ b/erts/emulator/beam/binary.c
@@ -322,40 +322,102 @@ BIF_RETTYPE binary_to_integer_2(BIF_ALIST_2)
 
 }
 
+static Eterm integer_to_binary(Process *c_p, Eterm num, int base)
+{
+    Eterm res;
+
+    if (is_small(num)) {
+        char s[128];
+        char *c = s;
+        Uint digits;
+
+        digits = Sint_to_buf(signed_val(num), base, &c, sizeof(s));
+        res = new_binary(c_p, (byte*)c, digits);
+    } else {
+        const int DIGITS_PER_RED = 16;
+        Uint digits, n;
+        byte *bytes;
+
+        digits = big_integer_estimate(num, base);
+
+        if ((digits / DIGITS_PER_RED) > ERTS_BIF_REDS_LEFT(c_p)) {
+            ErtsSchedulerData *esdp = erts_get_scheduler_data();
+
+            /* This could take a very long time, tell the caller to reschedule
+             * us to a dirty CPU scheduler if we aren't already on one. */
+            if (esdp->type == ERTS_SCHED_NORMAL) {
+                return THE_NON_VALUE;
+            }
+        } else {
+            BUMP_REDS(c_p, digits / DIGITS_PER_RED);
+        }
+
+        bytes = (byte*)erts_alloc(ERTS_ALC_T_TMP, sizeof(byte) * digits);
+        n = erts_big_to_binary_bytes(num, base, (char*)bytes, digits);
+        res = new_binary(c_p, bytes + digits - n, n);
+        erts_free(ERTS_ALC_T_TMP, (void*)bytes);
+    }
+
+    return res;
+}
+
 BIF_RETTYPE integer_to_binary_1(BIF_ALIST_1)
-{   
-    Uint size;
+{
     Eterm res;
 
     if (is_not_integer(BIF_ARG_1)) {
-	BIF_ERROR(BIF_P, BADARG);
+        BIF_ERROR(BIF_P, BADARG);
     }
 
-    if (is_small(BIF_ARG_1)) {
-	char *c;
-	struct Sint_buf ibuf;
+    res = integer_to_binary(BIF_P, BIF_ARG_1, 10);
+
+    if (is_non_value(res)) {
+        Eterm args[1];
+        args[0] = BIF_ARG_1;
+        return erts_schedule_bif(BIF_P,
+                                 args,
+                                 BIF_I,
+                                 integer_to_binary_1,
+                                 ERTS_SCHED_DIRTY_CPU,
+                                 am_erlang,
+                                 am_integer_to_binary,
+                                 1);
+    }
 
-	/* Enhancement: If we can calculate the buffer size exactly
-	 * we could avoid an unnecessary copy of buffers.
-	 * Useful if size determination is faster than a copy.
-	 */
-	c = Sint_to_buf(signed_val(BIF_ARG_1), &ibuf);
-	size = sys_strlen(c);
-	res = new_binary(BIF_P, (byte *)c, size);
-    } else {
-	byte* bytes;
-	Uint n = 0;
+    return res;
+}
 
-	/* Here we also have multiple copies of buffers
-	 * due to new_binary interface
-	 */
-	size = big_decimal_estimate(BIF_ARG_1) - 1; /* remove null */
-	bytes = (byte*) erts_alloc(ERTS_ALC_T_TMP, sizeof(byte)*size);
-	n = erts_big_to_binary_bytes(BIF_ARG_1, (char *)bytes, size);
-	res = new_binary(BIF_P, bytes + size - n, n);
-	erts_free(ERTS_ALC_T_TMP, (void *) bytes);
+BIF_RETTYPE integer_to_binary_2(BIF_ALIST_2)
+{
+    Eterm res;
+    SWord base;
+
+    if (is_not_integer(BIF_ARG_1) || is_not_small(BIF_ARG_2)) {
+        BIF_ERROR(BIF_P, BADARG);
+    }
+
+    base = signed_val(BIF_ARG_2);
+    if (base < 2 || base > 36) {
+        BIF_ERROR(BIF_P, BADARG);
     }
-    BIF_RET(res);
+
+    res = integer_to_binary(BIF_P, BIF_ARG_1, base);
+
+    if (is_non_value(res)) {
+        Eterm args[2];
+        args[0] = BIF_ARG_1;
+        args[1] = BIF_ARG_2;
+        return erts_schedule_bif(BIF_P,
+                                 args,
+                                 BIF_I,
+                                 integer_to_binary_2,
+                                 ERTS_SCHED_DIRTY_CPU,
+                                 am_erlang,
+                                 am_integer_to_binary,
+                                 2);
+    }
+
+    return res;
 }
 
 #define ERTS_B2L_BYTES_PER_REDUCTION 256
diff --git a/erts/emulator/beam/break.c b/erts/emulator/beam/break.c
index 9ff52c92b8..92009c2345 100644
--- a/erts/emulator/beam/break.c
+++ b/erts/emulator/beam/break.c
@@ -82,7 +82,7 @@ process_info(fmtfn_t to, void *to_arg)
 	     * they are most likely just created and has invalid data
 	     */
 	    if (!ERTS_PROC_IS_EXITING(p) && p->heap != NULL)
-		print_process_info(to, to_arg, p);
+		print_process_info(to, to_arg, p, 0);
 	}
     }
 
@@ -101,7 +101,7 @@ process_killer(void)
 	rp = erts_pix2proc(i);
 	if (rp && rp->i != ENULL) {
 	    int br;
-	    print_process_info(ERTS_PRINT_STDOUT, NULL, rp);
+	    print_process_info(ERTS_PRINT_STDOUT, NULL, rp, 0);
 	    erts_printf("(k)ill (n)ext (r)eturn:\n");
 	    while(1) {
 		if ((j = sys_get_key(0)) <= 0)
@@ -199,13 +199,14 @@ static void doit_print_monitor(ErtsMonitor *mon, void *vpcontext)
 			       
 /* Display info about an individual Erlang process */
 void
-print_process_info(fmtfn_t to, void *to_arg, Process *p)
+print_process_info(fmtfn_t to, void *to_arg, Process *p, ErtsProcLocks orig_locks)
 {
     int garbing = 0;
     int running = 0;
     Sint len;
     struct saved_calls *scb;
     erts_aint32_t state;
+    ErtsProcLocks locks = orig_locks;
 
     /* display the PID */
     erts_print(to, to_arg, "=proc:%T\n", p->common.id);
@@ -222,6 +223,22 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
 			| ERTS_PSFLG_DIRTY_RUNNING))
         running = 1;
 
+    if (!(locks & ERTS_PROC_LOCK_MAIN)) {
+        locks |= ERTS_PROC_LOCK_MAIN;
+        if (ERTS_IS_CRASH_DUMPING && running) {
+            if (erts_proc_trylock(p, locks)) {
+                /* crash dumping and main lock taken, this probably means that
+                   the process is doing a GC on a dirty-scheduler... so we cannot
+                   do erts_proc_sig_fetch as that would potentially cause a segfault */
+                locks = 0;
+            }
+        } else {
+            erts_proc_lock(p, locks);
+        }
+    } else {
+        ERTS_ASSERT(locks == ERTS_PROC_LOCK_MAIN && "Only main lock should be held");
+    }
+
     /*
      * If the process is registered as a global process, display the
      * registered name
@@ -251,13 +268,19 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
 
     erts_print(to, to_arg, "Spawned by: %T\n", p->parent);
 
-    erts_proc_lock(p, ERTS_PROC_LOCK_MSGQ);
-    len = erts_proc_sig_fetch(p);
-    erts_proc_unlock(p, ERTS_PROC_LOCK_MSGQ);
+    if (locks & ERTS_PROC_LOCK_MAIN) {
+        erts_proc_lock(p, ERTS_PROC_LOCK_MSGQ);
+        len = erts_proc_sig_fetch(p);
+        erts_proc_unlock(p, ERTS_PROC_LOCK_MSGQ);
+    } else {
+        len = p->sig_qs.len;
+    }
     erts_print(to, to_arg, "Message queue length: %d\n", len);
 
-    /* display the message queue only if there is anything in it */
-    if (!ERTS_IS_CRASH_DUMPING && p->sig_qs.first != NULL && !garbing) {
+    /* display the message queue only if there is anything in it
+       and we can do it safely */
+    if (!ERTS_IS_CRASH_DUMPING && p->sig_qs.first != NULL && !garbing
+        && (locks & ERTS_PROC_LOCK_MAIN)) {
 	erts_print(to, to_arg, "Message queue: [");
         ERTS_FOREACH_SIG_PRIVQS(
             p, mp,
@@ -357,6 +380,8 @@ print_process_info(fmtfn_t to, void *to_arg, Process *p)
     /* Display all states */
     erts_print(to, to_arg, "Internal State: ");
     erts_dump_extended_process_state(to, to_arg, state);
+
+    erts_proc_unlock(p, locks & ~orig_locks);
 }
 
 static void
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index 7fada0d548..6137edef1b 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -3139,6 +3139,8 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
 	DECL_AM(tag);
 	BIF_RET(AM_tag);
 #endif
+    } else if (ERTS_IS_ATOM_STR("system_logger", BIF_ARG_1)) {
+        BIF_RET(erts_get_system_logger());
     }
 
     BIF_ERROR(BIF_P, BADARG);
@@ -4608,6 +4610,7 @@ BIF_RETTYPE erts_debug_set_internal_state_2(BIF_ALIST_2)
 	    }
 	}
         else if (ERTS_IS_ATOM_STR("broken_halt", BIF_ARG_1)) {
+            erts_proc_unlock(BIF_P, ERTS_PROC_LOCK_MAIN);
             broken_halt_test(BIF_ARG_2);
         }
 	else if (ERTS_IS_ATOM_STR("unique_monotonic_integer_state", BIF_ARG_1)) {
diff --git a/erts/emulator/beam/erl_bif_port.c b/erts/emulator/beam/erl_bif_port.c
index 7fe4e02782..ed825d3dda 100644
--- a/erts/emulator/beam/erl_bif_port.c
+++ b/erts/emulator/beam/erl_bif_port.c
@@ -891,10 +891,6 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump)
 
 	    driver = &spawn_driver;
 	} else if (*tp == am_fd) { /* An fd port */
-	    int n;
-	    struct Sint_buf sbuf;
-	    char* p;
-
 	    if (arity != make_arityval(3)) {
 		goto badarg;
 	    }
@@ -904,15 +900,9 @@ open_port(Process* p, Eterm name, Eterm settings, int *err_typep, int *err_nump)
 	    opts.ifd = unsigned_val(tp[1]);
 	    opts.ofd = unsigned_val(tp[2]);
 
-	    /* Syntesize name from input and output descriptor. */
-	    name_buf = erts_alloc(ERTS_ALC_T_TMP,
-				  2*sizeof(struct Sint_buf) + 2); 
-	    p = Sint_to_buf(opts.ifd, &sbuf);
-	    n = sys_strlen(p);
-	    sys_strncpy(name_buf, p, n);
-	    name_buf[n] = '/';
-	    p = Sint_to_buf(opts.ofd, &sbuf);
-	    sys_strcpy(name_buf+n+1, p);
+            /* Syntesize name from input and output descriptor. */
+            name_buf = erts_alloc(ERTS_ALC_T_TMP, 256);
+            erts_snprintf(name_buf, 256, "%i/%i", opts.ifd, opts.ofd);
 
 	    driver = &fd_driver;
 	} else {
diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index f1d47326b4..e2c029c244 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -2470,7 +2470,7 @@ restart:
 	case matchProcessDump: {
 	    erts_dsprintf_buf_t *dsbufp = erts_create_tmp_dsbuf(0);
             ASSERT(c_p == self);
-	    print_process_info(ERTS_PRINT_DSBUF, (void *) dsbufp, c_p);
+	    print_process_info(ERTS_PRINT_DSBUF, (void *) dsbufp, c_p, ERTS_PROC_LOCK_MAIN);
 	    *esp++ = new_binary(build_proc, (byte *)dsbufp->str,
 				dsbufp->str_len);
 	    erts_destroy_tmp_dsbuf(dsbufp);
diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index d5dfb096b1..3a50b294d1 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -2438,27 +2438,9 @@ erts_copy_one_frag(Eterm** hpp, ErlOffHeap* off_heap,
 	    cpy_words:
 		ASSERT(sz >= cpy_sz);
 		sz -= cpy_sz;
-		while (cpy_sz >= 8) {
-		    cpy_sz -= 8;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		    *hp++ = *fhp++;
-		}
-		switch (cpy_sz) {
-		case 7: *hp++ = *fhp++;
-		case 6: *hp++ = *fhp++;
-		case 5: *hp++ = *fhp++;
-		case 4: *hp++ = *fhp++;
-		case 3: *hp++ = *fhp++;
-		case 2: *hp++ = *fhp++;
-		case 1: *hp++ = *fhp++;
-		default: break;
-		}
+                sys_memcpy(hp, fhp, cpy_sz * sizeof(Eterm));
+                hp += cpy_sz;
+                fhp += cpy_sz;
 		if (oh) {
 		    /* Add to offheap list */
 		    oh->next = off_heap->first;
@@ -2477,7 +2459,7 @@ erts_copy_one_frag(Eterm** hpp, ErlOffHeap* off_heap,
     *hpp = hp;
 
     for (i = 0; i < nrefs; i++) {
-	if (is_not_immed(refs[i]) && !erts_is_literal(refs[i],boxed_val(refs[i])))
+	if (is_not_immed(refs[i]) && !erts_is_literal(refs[i],ptr_val(refs[i])))
 	    refs[i] = offset_ptr(refs[i], offs);
     }
     bp->off_heap.first = NULL;
diff --git a/erts/emulator/beam/erl_init.c b/erts/emulator/beam/erl_init.c
index 99e788c718..41bec17dfa 100644
--- a/erts/emulator/beam/erl_init.c
+++ b/erts/emulator/beam/erl_init.c
@@ -376,6 +376,27 @@ erl_init(int ncpu,
 }
 
 static Eterm
+erl_spawn_system_process(Process* parent, Eterm mod, Eterm func, Eterm args,
+                         ErlSpawnOpts *so)
+{
+    Eterm res;
+    int arity;
+
+    ERTS_LC_ASSERT(ERTS_PROC_LOCK_MAIN & erts_proc_lc_my_proc_locks(parent));
+    arity = erts_list_length(args);
+
+    if (erts_find_function(mod, func, arity, erts_active_code_ix()) == NULL) {
+	erts_exit(ERTS_ERROR_EXIT, "No function %T:%T/%i\n", mod, func, arity);
+    }
+
+    so->flags |= SPO_SYSTEM_PROC;
+
+    res = erl_create_process(parent, mod, func, args, so);
+
+    return res;
+}
+
+static Eterm
 erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char** argv)
 {
     int i;
@@ -386,12 +407,6 @@ erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char**
     Process parent;
     ErlSpawnOpts so;
     Eterm env;
-    
-    start_mod = erts_atom_put((byte *) modname, sys_strlen(modname), ERTS_ATOM_ENC_LATIN1, 1);
-    if (erts_find_function(start_mod, am_start, 2,
-			   erts_active_code_ix()) == NULL) {
-	erts_exit(ERTS_ERROR_EXIT, "No function %s:start/2\n", modname);
-    }
 
     /*
      * We need a dummy parent process to be able to call erl_create_process().
@@ -399,6 +414,7 @@ erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char**
 
     erts_init_empty_process(&parent);
     erts_proc_lock(&parent, ERTS_PROC_LOCK_MAIN);
+
     hp = HAlloc(&parent, argc*2 + 4);
     args = NIL;
     for (i = argc-1; i >= 0; i--) {
@@ -411,44 +427,73 @@ erl_first_process_otp(char* modname, void* code, unsigned size, int argc, char**
     hp += 2;
     args = CONS(hp, env, args);
 
-    so.flags = erts_default_spo_flags|SPO_SYSTEM_PROC;
-    res = erl_create_process(&parent, start_mod, am_start, args, &so);
+    start_mod = erts_atom_put((byte *) modname, sys_strlen(modname),
+                              ERTS_ATOM_ENC_LATIN1, 1);
+
+    so.flags = erts_default_spo_flags;
+    res = erl_spawn_system_process(&parent, start_mod, am_start, args, &so);
+    ASSERT(is_internal_pid(res));
+
     erts_proc_unlock(&parent, ERTS_PROC_LOCK_MAIN);
     erts_cleanup_empty_process(&parent);
+
     return res;
 }
 
 static Eterm
 erl_system_process_otp(Eterm parent_pid, char* modname, int off_heap_msgq, int prio)
-{
-    Eterm start_mod;
-    Process* parent;
+{ 
+    Process *parent;
     ErlSpawnOpts so;
-    Eterm res;
-
-    start_mod = erts_atom_put((byte *) modname, sys_strlen(modname), ERTS_ATOM_ENC_LATIN1, 1);
-    if (erts_find_function(start_mod, am_start, 0,
-			   erts_active_code_ix()) == NULL) {
-	erts_exit(ERTS_ERROR_EXIT, "No function %s:start/0\n", modname);
-    }
+    Eterm mod, res;
 
     parent = erts_pid2proc(NULL, 0, parent_pid, ERTS_PROC_LOCK_MAIN);
+    mod = erts_atom_put((byte *) modname, sys_strlen(modname),
+                        ERTS_ATOM_ENC_LATIN1, 1);
+
+    so.flags = erts_default_spo_flags|SPO_USE_ARGS;
 
-    so.flags = erts_default_spo_flags|SPO_SYSTEM_PROC|SPO_USE_ARGS;
-    if (off_heap_msgq)
+    if (off_heap_msgq) {
         so.flags |= SPO_OFF_HEAP_MSGQ;
-    so.min_heap_size    = H_MIN_SIZE;
-    so.min_vheap_size   = BIN_VH_MIN_SIZE;
-    so.max_heap_size    = H_MAX_SIZE;
-    so.max_heap_flags   = H_MAX_FLAGS;
-    so.priority         = prio;
-    so.max_gen_gcs      = (Uint16) erts_atomic32_read_nob(&erts_max_gen_gcs);
-    so.scheduler        = 0;
-    res = erl_create_process(parent, start_mod, am_start, NIL, &so);
+    }
+
+    so.min_heap_size  = H_MIN_SIZE;
+    so.min_vheap_size = BIN_VH_MIN_SIZE;
+    so.max_heap_size  = H_MAX_SIZE;
+    so.max_heap_flags = H_MAX_FLAGS;
+    so.priority       = prio;
+    so.max_gen_gcs    = (Uint16) erts_atomic32_read_nob(&erts_max_gen_gcs);
+    so.scheduler      = 0;
+
+    res = erl_spawn_system_process(parent, mod, am_start, NIL, &so);
+    ASSERT(is_internal_pid(res));
+
     erts_proc_unlock(parent, ERTS_PROC_LOCK_MAIN);
+
     return res;
 }
 
+Eterm erts_internal_spawn_system_process_3(BIF_ALIST_3) {
+    Eterm mod, func, args, res;
+    ErlSpawnOpts so;
+
+    mod = BIF_ARG_1;
+    func = BIF_ARG_2;
+    args = BIF_ARG_3;
+
+    ASSERT(is_atom(mod));
+    ASSERT(is_atom(func));
+    ASSERT(erts_list_length(args) >= 0);
+
+    so.flags = erts_default_spo_flags;
+    res = erl_spawn_system_process(BIF_P, mod, func, args, &so);
+
+    if (is_non_value(res)) {
+        BIF_ERROR(BIF_P, so.error_code);
+    }
+
+    BIF_RET(res);
+}
 
 Eterm
 erts_preloaded(Process* p)
diff --git a/erts/emulator/beam/erl_printf_term.c b/erts/emulator/beam/erl_printf_term.c
index 990a01b96f..9cfb7fc681 100644
--- a/erts/emulator/beam/erl_printf_term.c
+++ b/erts/emulator/beam/erl_printf_term.c
@@ -364,13 +364,13 @@ print_term(fmtfn_t fn, void* arg, Eterm obj, long *dcount) {
 	    int print_res;
 	    char def_buf[64];
 	    char *buf, *big_str;
-	    Uint sz = (Uint) big_decimal_estimate(wobj);
+	    Uint sz = (Uint) big_integer_estimate(wobj, 10);
 	    sz++;
 	    if (sz <= 64)
 		buf = &def_buf[0];
 	    else
 		buf = erts_alloc(ERTS_ALC_T_TMP, sz);
-	    big_str = erts_big_to_string(wobj, buf, sz);
+	    big_str = erts_big_to_string(wobj, 10, buf, sz);
 	    print_res = erts_printf_string(fn, arg, big_str);
 	    if (buf != &def_buf[0])
 		erts_free(ERTS_ALC_T_TMP, (void *) buf);
diff --git a/erts/emulator/beam/erl_proc_sig_queue.c b/erts/emulator/beam/erl_proc_sig_queue.c
index f343e984f7..18418a76e1 100644
--- a/erts/emulator/beam/erl_proc_sig_queue.c
+++ b/erts/emulator/beam/erl_proc_sig_queue.c
@@ -3812,7 +3812,6 @@ clear_seq_trace_token(ErtsMessage *sig)
 void
 erts_proc_sig_clear_seq_trace_tokens(Process *c_p)
 {
-    ASSERT(erts_thr_progress_is_blocking());
     erts_proc_sig_fetch(c_p);
     ERTS_FOREACH_SIG_PRIVQS(c_p, sig, clear_seq_trace_token(sig));
 }
diff --git a/erts/emulator/beam/erl_proc_sig_queue.h b/erts/emulator/beam/erl_proc_sig_queue.h
index 3fc2d06b2d..6b065a7add 100644
--- a/erts/emulator/beam/erl_proc_sig_queue.h
+++ b/erts/emulator/beam/erl_proc_sig_queue.h
@@ -989,8 +989,7 @@ erts_proc_sig_fetch(Process *proc)
     Sint res = 0;
     ErtsSignal *sig;
 
-    ERTS_LC_ASSERT(erts_thr_progress_is_blocking()
-                   || ERTS_PROC_IS_EXITING(proc)
+    ERTS_LC_ASSERT(ERTS_PROC_IS_EXITING(proc)
                    || ((erts_proc_lc_my_proc_locks(proc)
                         & (ERTS_PROC_LOCK_MAIN
                            | ERTS_PROC_LOCK_MSGQ))
diff --git a/erts/emulator/beam/erl_trace.c b/erts/emulator/beam/erl_trace.c
index 2350d4c02f..701fb38147 100644
--- a/erts/emulator/beam/erl_trace.c
+++ b/erts/emulator/beam/erl_trace.c
@@ -72,6 +72,7 @@ static ErtsTracer default_port_tracer;
 
 static Eterm system_monitor;
 static Eterm system_profile;
+static erts_aint_t system_logger;
 
 #ifdef HAVE_ERTS_NOW_CPU
 int erts_cpu_timestamp;
@@ -340,6 +341,7 @@ void erts_init_trace(void) {
     default_port_trace_flags = F_INITIAL_TRACE_FLAGS;
     default_port_tracer = erts_tracer_nil;
     system_seq_tracer = erts_tracer_nil;
+    erts_atomic_init_nob(&system_logger, am_logger);
     init_sys_msg_dispatcher();
     init_tracer_nif();
 }
@@ -2027,10 +2029,24 @@ enqueue_sys_msg(enum ErtsSysMsgType type,
     erts_mtx_unlock(&smq_mtx);
 }
 
+Eterm
+erts_get_system_logger(void)
+{
+    return (Eterm)erts_atomic_read_nob(&system_logger);
+}
+
+Eterm
+erts_set_system_logger(Eterm logger)
+{
+    if (logger != am_logger && logger != am_undefined && !is_internal_pid(logger))
+        return THE_NON_VALUE;
+    return (Eterm)erts_atomic_xchg_nob(&system_logger, logger);
+}
+
 void
 erts_queue_error_logger_message(Eterm from, Eterm msg, ErlHeapFragment *bp)
 {
-    enqueue_sys_msg(SYS_MSG_TYPE_ERRLGR, from, am_logger, msg, bp);
+    enqueue_sys_msg(SYS_MSG_TYPE_ERRLGR, from, erts_get_system_logger(), msg, bp);
 }
 
 void
@@ -2271,7 +2287,7 @@ sys_msg_dispatcher_func(void *unused)
 		}
 		break;
 	    case SYS_MSG_TYPE_ERRLGR:
-		receiver = am_logger;
+		receiver = smqp->to;
 		break;
 	    default:
 		receiver = NIL;
@@ -2285,8 +2301,15 @@ sys_msg_dispatcher_func(void *unused)
 	    if (is_internal_pid(receiver)) {
 		proc = erts_pid2proc(NULL, 0, receiver, proc_locks);
 		if (!proc) {
-		    /* Bad tracer */
-		    goto failure;
+                    if (smqp->type == SYS_MSG_TYPE_ERRLGR) {
+                        /* Bad logger process, send to kernel 'logger' process */
+                        erts_set_system_logger(am_logger);
+                        receiver = erts_get_system_logger();
+                        goto logger;
+                    } else {
+                        /* Bad tracer */
+                        goto failure;
+                    }
 		}
 		else {
 		    ErtsMessage *mp;
@@ -2299,9 +2322,9 @@ sys_msg_dispatcher_func(void *unused)
 #endif
 		    erts_proc_unlock(proc, proc_locks);
 		}
-	    }
-	    else if (receiver == am_logger) {
-		proc = erts_whereis_process(NULL,0,receiver,proc_locks,0);
+	    } else if (receiver == am_logger) {
+            logger:
+		proc = erts_whereis_process(NULL,0,am_logger,proc_locks,0);
 		if (!proc)
 		    goto failure;
 		else if (smqp->from == proc->common.id)
@@ -2309,7 +2332,10 @@ sys_msg_dispatcher_func(void *unused)
 		else
 		    goto queue_proc_msg;
 	    }
-	    else if (is_internal_port(receiver)) {
+            else if (receiver == am_undefined) {
+                goto drop_sys_msg;
+	    }
+            else if (is_internal_port(receiver)) {
 		port = erts_thr_id2port_sflgs(receiver,
 					      ERTS_PORT_SFLGS_INVALID_TRACER_LOOKUP);
 		if (!port)
@@ -2366,7 +2392,7 @@ erts_foreach_sys_msg_in_q(void (*func)(Eterm,
 	    to = erts_get_system_profile();
 	    break;
 	case SYS_MSG_TYPE_ERRLGR:
-	    to = am_logger;
+	    to = erts_get_system_logger();
 	    break;
 	default:
 	    to = NIL;
diff --git a/erts/emulator/beam/erl_trace.h b/erts/emulator/beam/erl_trace.h
index bccf31606e..b7844d1cb0 100644
--- a/erts/emulator/beam/erl_trace.h
+++ b/erts/emulator/beam/erl_trace.h
@@ -94,6 +94,8 @@ void erts_foreach_sys_msg_in_q(void (*func)(Eterm,
 					    Eterm,
 					    Eterm,
 					    ErlHeapFragment *));
+Eterm erts_set_system_logger(Eterm);
+Eterm erts_get_system_logger(void);
 void erts_queue_error_logger_message(Eterm, Eterm, ErlHeapFragment *);
 void erts_send_sys_msg_proc(Eterm, Eterm, Eterm, ErlHeapFragment *);
 
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index 0631404599..36b753ca9c 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -962,7 +962,7 @@ void init_break_handler(void);
 void erts_set_ignore_break(void);
 void erts_replace_intr(void);
 void process_info(fmtfn_t, void *);
-void print_process_info(fmtfn_t, void *, Process*);
+void print_process_info(fmtfn_t, void *, Process*, ErtsProcLocks);
 void info(fmtfn_t, void *);
 void loaded(fmtfn_t, void *);
 void erts_print_base64(fmtfn_t to, void *to_arg, byte* src, Uint size);
@@ -1303,14 +1303,7 @@ Sint intlist_to_buf(Eterm, char*, Sint); /* most callers pass plain char*'s */
 int erts_unicode_list_to_buf(Eterm list, byte *buf, Sint len, Sint* written);
 Sint erts_unicode_list_to_buf_len(Eterm list);
 
-struct Sint_buf {
-#if defined(ARCH_64)
-    char s[22];
-#else
-    char s[12];
-#endif
-};	
-char* Sint_to_buf(Sint, struct Sint_buf*);
+int Sint_to_buf(Sint num, int base, char **buf_p, size_t buf_size);
 
 #define ERTS_IOLIST_STATE_INITER(C_P, OBJ)	\
     {(C_P), 0, 0, (OBJ), {NULL, NULL, NULL, ERTS_ALC_T_INVALID}, 0, 0}
diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index d81bd89a48..a231638b50 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -3681,30 +3681,47 @@ erts_unicode_list_to_buf_len(Eterm list)
     }
 }
 
-/*
-** Convert an integer to a byte list
-** return pointer to converted stuff (need not to be at start of buf!)
-*/
-char* Sint_to_buf(Sint n, struct Sint_buf *buf)
+/* Prints an integer in the given base, returning the number of digits printed.
+ *
+ * (*buf) is a pointer to the buffer, and is set to the start of the string
+ * when returning. */
+int Sint_to_buf(Sint n, int base, char **buf, size_t buf_size)
 {
-    char* p = &buf->s[sizeof(buf->s)-1];
-    int sign = 0;
-
-    *p-- = '\0'; /* null terminate */
-    if (n == 0)
-	*p-- = '0';
-    else if (n < 0) {
-	sign = 1;
-	n = -n;
+    char *p = &(*buf)[buf_size - 1];
+    int sign = 0, size = 0;
+
+    ASSERT(base >= 2 && base <= 36);
+
+    if (n == 0) {
+        *p-- = '0';
+        size++;
+    } else if (n < 0) {
+        sign = 1;
+        n = -n;
     }
 
     while (n != 0) {
-	*p-- = (n % 10) + '0';
-	n /= 10;
+        int digit = n % base;
+
+        if (digit < 10) {
+            *p-- = '0' + digit;
+        } else {
+            *p-- = 'A' + (digit - 10);
+        }
+
+        size++;
+
+        n /= base;
     }
-    if (sign)
-	*p-- = '-';
-    return p+1;
+
+    if (sign) {
+        *p-- = '-';
+        size++;
+    }
+
+    *buf = p + 1;
+
+    return size;
 }
 
 /* Build a list of integers in some safe memory area
@@ -4771,58 +4788,3 @@ erts_ptr_id(void *ptr)
     return ptr;
 }
 
-#ifdef DEBUG
-/*
- * Handy functions when using a debugger - don't use in the code!
- */
-
-void upp(byte *buf, size_t sz)
-{
-    bin_write(ERTS_PRINT_STDERR, NULL, buf, sz);
-}
-
-void pat(Eterm atom)
-{
-    upp(atom_tab(atom_val(atom))->name,
-	atom_tab(atom_val(atom))->len);
-}
-
-
-void pinfo()
-{
-    process_info(ERTS_PRINT_STDOUT, NULL);
-}
-
-
-void pp(p)
-Process *p;
-{
-    if(p)
-	print_process_info(ERTS_PRINT_STDERR, NULL, p);
-}
-
-void ppi(Eterm pid)
-{
-    pp(erts_proc_lookup(pid));
-}
-
-void td(Eterm x)
-{
-    erts_fprintf(stderr, "%T\n", x);
-}
-
-void
-ps(Process* p, Eterm* stop)
-{
-    Eterm* sp = STACK_START(p) - 1;
-
-    if (stop <= STACK_END(p)) {
-        stop = STACK_END(p) + 1;
-    }
-
-    while(sp >= stop) {
-	erts_printf("%p: %.75T\n", sp, *sp);
-	sp--;
-    }
-}
-#endif