Section 6.1

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Changes:

With Verilog-2001, users can add named attributes (properties) to Verilog objects, such as modules, instances, wires, etc. Attributes can also be specified on SystemVerilog interfaces. Attributes can also be specified on the extended SystemVerilog constructs and are included as part of the BNF (See Annex A). SystemVerilog also defines a default data type for attributes.

Remove editor’s note:

Editor’s Note: What other new SV objects can have attributes? (program blocks, assertions, ...)? I will update the BNF syntax excerpt once that has been determined. Will additional text for these other objects need to be added in this section? I suggest this entire section is not needed. The BNF for each new SV object shows where attributes are legal, and does not need to be covered in a special section. The only change to the attribute construct itself in SystemVerilog 3.0 is the default data type of bit. Verilog-2001 says the default value is 1 (true). Is it necessary for SystemVerilog to specify the data type of that value in order for attributes to work with SystemVerilog constructs? If not, then let the IEEE determine the appropriate default data type, the IEEE sees a need for one.

Section 6.2

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Changes (delete Syntax 6-1 plus the other items as indicated below):

6.2 Attribute syntax for interfaces Default attribute type

interface_declaration ::= // from Annex A.1.3

{ attribute_instance } interface interface_identifier [ parameter_port_list ]

[ list_of_ports ] ; [unit] [precision] { interface_item }

endinterface [: interface_identifier]

| { attribute_instance } interface interface_identifier [ parameter_port_list ]

[ list_of_port_declarations ] ; [unit] [precision] { non_port_interface_item }

endinterface [: interface_identifier]

interface_item ::= // from Annex A.1.6

port_declaration

| non_port_interface_item

attribute_instance ::= (* attr_spec { , attr_spec } *) // from Annex A.9.1

attr_spec ::=

attr_name = constant_expression

| attr_name

attr_name ::= identifier

Syntax 6-1—Interface attribute syntax (excerpt from Annex A)

An example of defining an attribute for an interface declaration is:

(* interface_att = 10 *) interface bus1.... endinterface

The default type of an attribute with no value is bit, with a value of 1. Otherwise, the attribute takes the type of the expression.

The modport declaration can be preceded by an attribute instance, like any other interface item.

Remove editor’s note:

Editor’s Note: Update preceding BNF excerpt with new BNF, once available.