ProtectedTypeUpdates < P1076

P1076 Web>Vhdl2019CollectedRequirements>ProtectedTypeUpdates (2020-06-12, JimLewis) (raw view)EditAttach
---+ Depricated: Protected Type Update - Now separate proposals

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---++ Proposal Information
   * State of this Proposal: Raw / Stream of Conscious
   * Current Owner: JimLewis, ...
   * Contributors: JimLewis, ...
   * Date Proposed: 2012-Jan-05
   * Date Last Updated: 2012-Aug-10
   * Priority:
   * Complexity:
   * Focus: Testbench
   * Related Issues: None
   * Competing Issues: None
---++ Requirement Summary

Collection of potential updates to protected types

---++ What is the nature of a protected type?

A protected type is a container. It has members in the form of private variables and subprogram methods (aka: procedures and functions). Variables inside a protected type are local and cannot be modified directly. Instead they are modified by calls to the protected type methods.

As a container, protected types are useful for creating data structures, such as scoreboards, FIFOs, memories, and functional coverage models.

A protected type is used with a shared variable (when declared in a 
concurrent declaration region - such as an architecture) or a 
regular variable (when declared in a sequential declaration region - such as a process). 

However, calling it a variable in some ways is troubling. 
Assignment operations are not supported for protected type. 
So instead, a variable of a protected type is simply a handle 
that is used to call methods within the protected type.

With modification, it has potential to be an abstract interface or 
channel between objects (such as entities).

---++ Proposed 202X:  Mechanism to Suspend and Wake on Event

See proposal: [[ProtectedTypeWaitSignal][Protected Types: Wait and Private Signals]]

Motivation: Handshaking between different models connected by a shared variable.

---++ Proposed 202X:  Private Signal Members

See proposal: [[ProtectedTypeWaitSignal][Protected Types: Wait and Private Signals]]

Motivation: Event triggers

---++ Proposed 202X:  Public Signal Members

See proposal: [[ProtectedTypesPublicSignal][Protected Types with Public Signals]]

Motivation: Abstract interface/Communication Channel. Connection similar to a record.

---++ Clarified LRM in 2019:  Attributes to Determine Declaration Context

See proposal: [[PathnameSharedVarSubprograms][Paths to Protected Type Instances and Subprogram Calls]]

Motivation: get 'instance_name and 'path_name of corresponding variable / shared variable declaration

---++ Done 2019:  Usage on Entity Interfaces

See proposal: [[ProtectedTypeEntity][Shared Variables on Entity Interface]]

Motivation: Abstract interface/Communication Channel

---++ Done 2019:  File Parameters on Protected Type Methods

See proposal [[MethodParametersAccessTypes][Allow Protected Type Method Parameters to be ...]]

---++ Done 2019:  Alias to Methods

See proposal: [[ProtectedTypesAliases][Protected Types and Aliases]]

Motivation: allow subprograms to have alternate names. Helps with long term maintence of subprograms where a name change may be necessary to align with another group's methodology.

---++ Done 2019:  Composites of PTs

See proposal: [[P1076.CompositesProtectedTypes][composites of protected types]]

Arrays and records with PTs as elements.

Uses: Arrays of scoreboards, Arrays of Coverage Models, Arrays of Interfaces, ...

---++ Done 2019:  Function with protected type inputs

See Proposal: [[FunctionInterface][Allow access and protected type parameters on function interfaces]]

---++ Done 2019:  Generics on Protected Types

See proposal: [[GenericTypes][Generics on Protected Types]]
Topic revision: r13 - 2020-06-12 - 05:58:30 - JimLewis
P1076