The modifiable attribute specifies whether the associated transaction is modifiable.
The methods set_modifiable() and set_cacheable() must set this attribute to the value passed as argument. The methods is_modifiable() and is_cacheable() must return the value of this attribute.
For write transactions, a number of different writes can be merged together. For read transactions, a location can be pre-fetched or can be fetched only once for multiple reads. To determine if a transaction must be cached, use this attribute with the read allocate and write allocate attributes.
The default value of this attribute must be false.
This attribute is specific to the AXI and AHB buses. It is ignored for transactions modeling transfers on the APB bus.
The cacheable attribute used by the AXI3 and AHB buses has been renamed this attribute for AXI4 and ACE to better describe the required function of the attribute. The actual functionality is unchanged.