Refactor/cleanup binary_to_term impl (dec_term)

erts/emulator/beam/atom.h

@@ -63,6 +63,7 @@ extern IndexTable erts_atom_table;
 ERTS_GLB_INLINE Atom* atom_tab(Uint i);
 ERTS_GLB_INLINE int erts_is_atom_utf8_bytes(byte *text, size_t len, Eterm term);
 ERTS_GLB_INLINE int erts_is_atom_str(const char *str, Eterm term, int is_latin1);
+ERTS_GLB_INLINE int erts_is_atom_index_ok(Uint ix);
 
 const byte *erts_atom_get_name(const Atom *atom);
 
@@ -119,6 +120,21 @@ ERTS_GLB_INLINE int erts_is_atom_str(const char *str, Eterm term, int is_latin1)
     return *s == '\0';
 }
 
+ERTS_GLB_INLINE int erts_is_atom_index_ok(Uint ix)
+{
+    /*
+     * This is technincally a thread-unsafe read, but we assume
+     * + the hardware will get us a constistent integer value even during
+     *   concurrent writes.
+     * + the tested 'ix' (if ok) comes from an earlier read of 'entries'
+     *   and 'entries' is never decremented.
+     *
+     * So we don't care if we race and miss some unrelated increments.
+     */
+    return ix < (Uint)erts_atom_table.entries;
+}
+
+
 #endif
 
 typedef enum {

erts/emulator/beam/bif.c

@@ -480,7 +480,6 @@ demonitor(Process *c_p, Eterm ref, Eterm *multip)
    }
    case ERTS_ML_STATE_ALIAS_ONCE:
    case ERTS_ML_STATE_ALIAS_DEMONITOR:
-       /* fall through... */
    default:
        erts_monitor_tree_delete(&ERTS_P_MONITORS(c_p), mon);
        if (mon->flags & ERTS_ML_FLG_PRIO_ML)
@@ -641,8 +640,7 @@ BIF_RETTYPE demonitor_2(BIF_ALIST_2)
 	    BIF_TRAP3(flush_monitor_messages_trap, BIF_P,
 		      BIF_ARG_1, multi, res);
 	}
-        /* Fall through... */
-
+        ERTS_FALLTHROUGH();
     case am_true:
 	if (multi == am_true && flush)
 	    goto flush_messages;
@@ -1136,12 +1134,13 @@ BIF_RETTYPE erts_internal_spawn_request_4(BIF_ALIST_4)
 
 badarg:
     BIF_RET(am_badarg);
+
 system_limit:
     error = am_system_limit;
     goto send_error;
+
 badopt:
     error = am_badopt;
-    /* fall through... */
 send_error: {
         Eterm ref = erts_make_ref(BIF_P);
         if (!(so.flags & SPO_NO_EMSG))
@@ -2208,7 +2207,7 @@ BIF_RETTYPE process_flag_2(BIF_ALIST_2)
 	       BIF_RET(old_value);
            }
        }
-       /* Fall through and try process_flag_aux() ... */
+       /* Continue and try process_flag_aux() ... */
    }
 
    old_value = process_flag_aux(BIF_P, NULL, BIF_ARG_1, BIF_ARG_2);
@@ -2397,7 +2396,7 @@ static Sint remote_send(Process *p, DistEntry *dep,
             res = 0;
             break;
         }
-        /* Fall through... */
+        ERTS_FALLTHROUGH();
     case ERTS_DSIG_PREP_PENDING: {
 
         code = erts_dsig_send_msg(&ctx, to, full_to, msg, prio);
@@ -2571,7 +2570,7 @@ do_send(Process *p, Eterm to, Eterm msg, Eterm return_term, Eterm *refp,
 		    ret_val = SEND_YIELD_RETURN;
 		    break;
 		}
-		/* Fall through */
+		ERTS_FALLTHROUGH();
 	    case ERTS_PORT_OP_SCHEDULED:
 		if (is_not_nil(*refp)) {
 		    ASSERT(is_internal_ordinary_ref(*refp));

erts/emulator/beam/copy.c

@@ -705,7 +705,6 @@ Eterm copy_struct_x(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap,
 		break;
 	    }
 	    argp = hp++;
-	    /* Fall through */
 
 	L_copy_list:
 	    tailp = argp;
@@ -916,7 +915,7 @@ Eterm copy_struct_x(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap,
 		    erts_refc_inc(&mreft->mb->intern.refc, 2);
 		    goto L_off_heap_node_container_common;
 		}
-		/* Fall through... */
+                ERTS_FALLTHROUGH();
 	    default:
 		i = thing_arityval(hdr)+1;
 		hbot -= i;
@@ -1723,7 +1722,7 @@ Uint copy_shared_perform_x(Eterm obj, Uint size, erts_shcopy_t *info,
 		    erts_refc_inc(&mreft->mb->intern.refc, 2);
 		    goto off_heap_node_container_common;
 		}
-		/* Fall through... */
+                ERTS_FALLTHROUGH();
 	    default:
 		sz = thing_arityval(hdr);
 		*resp = make_boxed(hp);

erts/emulator/beam/dist.c

@@ -2131,7 +2131,7 @@ int erts_net_message(Port *prt,
             }
         }
 
-        /* fall through, the first fragment in the sequence was the last fragment */
+        /* The first fragment in the sequence was also the last fragment */
         ERTS_FALLTHROUGH();
     case ERTS_PREP_DIST_EXT_FRAG_CONT: {
         DistSeqNode *seq;
@@ -2461,8 +2461,7 @@ int erts_net_message(Port *prt,
 	if (tuple_arity != 5) {
 	    goto invalid_message;
 	}
-
-	/* Fall through ... */
+	ERTS_FALLTHROUGH();
     case DOP_REG_SEND:
 	/* {DOP_REG_SEND, From, Cookie, ToName} -- Message */
 	/* {DOP_REG_SEND_TT, From, Cookie, ToName, TraceToken} -- Message */
@@ -6091,7 +6090,7 @@ BIF_RETTYPE erts_internal_dist_spawn_request_4(BIF_ALIST_4)
             erts_de_runlock(dep);
             goto notsup;
         }
-        /* Fall through... */
+        ERTS_FALLTHROUGH();
     case ERTS_DSIG_PREP_PENDING: {
         int inserted;
         ErtsMonitorData *mdp;
@@ -6200,9 +6199,9 @@ BIF_RETTYPE erts_internal_dist_spawn_request_4(BIF_ALIST_4)
 notsup:
     error = am_notsup;
     goto send_error;
+
 badopt:
     error = am_badopt;
-    /* fall through... */
 send_error:
     ASSERT(is_value(ok_result));
     if (!(monitor_oflags & ERTS_ML_FLG_SPAWN_NO_EMSG))
@@ -6578,7 +6577,7 @@ monitor_node(Process* p, Eterm Node, Eterm Bool, Eterm Options)
 		erts_de_runlock(dep);
 		goto do_trap;
 	    }
-	    /*fall through*/
+	    ERTS_FALLTHROUGH();
         case ERTS_DSIG_PREP_CONNECTED: {
             ErtsMonitor *mon;
             ErtsMonitorDataExtended *mdep;

erts/emulator/beam/emu/emu_load.c

@@ -948,7 +948,7 @@ int beam_load_emit_op(LoaderState *stp, BeamOp *tmp_op) {
                 break;
             case TAG_n:
                 ASSERT(tmp_op->a[arg].val == NIL);
-                /* ! Fall through ! */
+                ERTS_FALLTHROUGH();
             case TAG_a:
                 code[ci++] = tmp_op->a[arg].val;
                 break;

erts/emulator/beam/erl_arith.c

@@ -260,7 +260,6 @@ erts_shift(Process* p, Eterm arg1, Eterm arg2, int right)
                 }
 		BIF_ERROR(p, SYSTEM_LIMIT);
 	    }
-	     /* Fall through if the left argument is not an integer. */
 	}
     }
     BIF_ERROR(p, BADARITH);
@@ -888,7 +887,7 @@ erts_mul_add(Process* p, Eterm arg1, Eterm arg2, Eterm arg3, Eterm* pp)
             break;
         }
         big_arg1 = small_to_big(signed_val(big_arg1), tmp_big1);
-        /* Fall through */
+        ERTS_FALLTHROUGH();
     case TAG_PRIMARY_BOXED:
         hdr = *boxed_val(big_arg1);
         switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
@@ -900,7 +899,7 @@ erts_mul_add(Process* p, Eterm arg1, Eterm arg2, Eterm arg3, Eterm* pp)
                     break;
                 }
                 big_arg2 = small_to_big(signed_val(big_arg2), tmp_big2);
-                /* Fall through */
+                ERTS_FALLTHROUGH();
             case TAG_PRIMARY_BOXED:
                 hdr = *boxed_val(big_arg2);
                 switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
@@ -912,7 +911,7 @@ erts_mul_add(Process* p, Eterm arg1, Eterm arg2, Eterm arg3, Eterm* pp)
                             break;
                         }
                         big_arg3 = small_to_big(signed_val(big_arg3), tmp_big3);
-                        /* Fall through */
+                        ERTS_FALLTHROUGH();
                     case TAG_PRIMARY_BOXED:
                         hdr = *boxed_val(big_arg3);
                         switch ((hdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
@@ -1131,7 +1130,7 @@ int erts_int_div_rem(Process* p, Eterm arg1, Eterm arg2, Eterm *q, Eterm *r)
         ASSERT(rhs == make_small(-1));
         lhs = small_to_big(signed_val(lhs), tmp_big1);
 
-        /* ! Fall through ! */
+        ERTS_FALLTHROUGH();
     case BIG_SMALL:
         rhs = small_to_big(signed_val(rhs), tmp_big2);
         break;

erts/emulator/beam/erl_bif_lists.c

@@ -519,7 +519,7 @@ static void subtract_ctx_move(ErtsSubtractContext *from,
             break;
         case SUBTRACT_STAGE_SET_FINISH:
             uses_result_cdr = 1;
-            /* FALL THROUGH */
+            ERTS_FALLTHROUGH();
         case SUBTRACT_STAGE_SET_BUILD:
             to->u.rhs_set.alloc_start = from->u.rhs_set.alloc_start;
             to->u.rhs_set.alloc = from->u.rhs_set.alloc;

erts/emulator/beam/erl_bif_port.c

@@ -220,7 +220,7 @@ BIF_RETTYPE erts_internal_port_command_3(BIF_ALIST_3)
 	    break;
 	case ERTS_PORT_OP_BUSY_SCHEDULED:
 	    ASSERT(!(flags & ERTS_PORT_SIG_FLG_FORCE));
-	    /* Fall through... */
+            ERTS_FALLTHROUGH();
 	case ERTS_PORT_OP_SCHEDULED:
 	    ASSERT(is_internal_ordinary_ref(ref));
 	    /* Signal order preserved by reply... */

erts/emulator/beam/erl_bif_re.c

@@ -1767,7 +1767,6 @@ re_run(Process *p, Eterm arg1, Eterm arg2, Eterm arg3, bool first)
         case PCRE2_ERROR_UTF8_ERR20:
         case PCRE2_ERROR_UTF8_ERR21:
             BUMP_ALL_REDS(p); /* Unknown amount of work done... */
-            /* Fall through for badarg... */
             ERTS_FALLTHROUGH();
 
         case PCRE2_ERROR_BADOFFSET:
@@ -1886,7 +1885,6 @@ static BIF_RETTYPE re_match_trap(BIF_ALIST_3)
         case PCRE2_ERROR_UTF8_ERR20:
         case PCRE2_ERROR_UTF8_ERR21:
             BUMP_ALL_REDS(BIF_P); /* Unknown amount of work done... */
-            /* Fall through for badarg... */
             ERTS_FALLTHROUGH();
 
         case PCRE2_ERROR_BADOFFSET:

erts/emulator/beam/erl_bif_trace.c

@@ -2666,7 +2666,7 @@ erts_finish_breakpointing(void)
 	    }
             /* Neither local or global set for event tracing */
 	}
-        /* Nothing to do here. Fall through to next stage. */
+        /* Nothing to do here. Continue to next stage. */
         finish_bp.current++;
         ERTS_FALLTHROUGH();
     case 1:
@@ -2703,7 +2703,7 @@ erts_finish_breakpointing(void)
         if (finish_bp.local || finish_bp.global) {
             return 1;
         }
-        /* Nothing done here. Fall through to next stage. */
+        /* Nothing done here. Continue to next stage. */
         finish_bp.current++;
         ERTS_FALLTHROUGH();
     case 3:

erts/emulator/beam/erl_db.c

@@ -1493,7 +1493,7 @@ do_update_counter(Process *p, DbTable* tb,
 	    else if (is_not_small(warp)) {
 		goto finalize;
 	    }
-	    /* Fall through */
+            ERTS_FALLTHROUGH();
 	case 2:
 	    if (!is_small(tpl[1])) {
 		goto finalize;

erts/emulator/beam/erl_db_util.c

@@ -2050,7 +2050,7 @@ Binary *db_match_compile(Eterm *matchexpr,
 #endif
 
     /* 
-     * Fall through to cleanup code, but context.save should not be free'd
+     * Continue to cleanup code, but context.save should not be free'd
      */  
     context.save = NULL;
 error: /* Here is were we land when compilation failed. */
@@ -5606,8 +5606,8 @@ static DMCRet dmc_expr(DMCContext *context,
 		!= retOk)
 		return ret;
 	    break;
-	}	    
-	/* Fall through */
+	}
+        ERTS_FALLTHROUGH();
     default:
     simple_term:
 	*constant = true;
@@ -5861,7 +5861,7 @@ static Uint my_size_object(Eterm t, bool is_hashmap_node)
             }
             break;
         }
-        /* fall through */
+        ERTS_FALLTHROUGH();
     default:
 	sum += size_object(t);
 	break;