Procedural blocks and expressions

[GlebChili]

No description provided.

[buzden]

(==) = isYes .: decEq

[buzden]

Should be done in Test.Verilog.ProceduralBlock.Derived

[buzden]

@L3odr0id, I' d like to hear your optinion on:

• how proposed expressions are modelled;
• whether or not proposed expressions are usable in your part of the model;
• this proposition contains some notion of type compatibility; is it correct and how does it correspond to the notion of port assignability in your part of the model; whether they should be harmonised?

[L3odr0id]

I think that the result of each specific operation isn't that important. Do we really need to declare a new constructor for each operation? Maybe we could, for example, define a single constructor for all binary bitwise, modulus, shift operations, then a single constructor for all arithmetic and logical operations etc. Of course, to create such group constructors, it is necessary to check which operand data types each operation supports.

Then we could implement a non-deterministic printer. For example, for the binary operation with integral operands we can choose and print any symbol like & | >> <<

There is a full list of operators from IEEE:

||| Table 11-1—Operators and data types
||| | Operator Token      | Name                                  | Operand Data Types                  |
||| |---------------------|---------------------------------------|-------------------------------------|
||| | =                   | Binary assignment operator            | Any                                 |
||| | += -= /= *=         | Binary arithmetic assignment operators| Integral, real, shortreal           |
||| | %=                  | Binary arithmetic modulus assignment  | Integral                            |
||| | &= |= ^=            | Binary bitwise assignment operators   | Integral                            |
||| | >>= <<=             | Binary logical shift assignment       | Integral                            |
||| | >>>= <<<=           | Binary arithmetic shift assignment    | Integral                            |
||| | ?:                  | Conditional operator                  | Any                                 |
||| | + -                 | Unary arithmetic operators            | Integral, real, shortreal           |
||| | ~                   | Unary bitwise negation operator       | Integral                            |
||| | !                   | Unary logical negation operator       | Integral, real, shortreal           |
||| | & ~& | ~| ^ ~^ ^~   | Unary reduction operators             | Integral                            |
||| | + - * / **          | Binary arithmetic operators           | Integral, real, shortreal           |
||| | %                   | Binary arithmetic modulus operator    | Integral                            |
||| | & | ^ ^~ ~^         | Binary bitwise operators              | Integral                            |
||| | >> <<               | Binary logical shift operators        | Integral                            |
||| | >>> <<<             | Binary arithmetic shift operators     | Integral                            |
||| | && || –> <–>        | Binary logical operators              | Integral, real, shortreal           |
||| | < <= > >=           | Binary relational operators           | Integral, real, shortreal           |
||| | === !==             | Binary case equality operators        | Any except real and shortreal       |
||| | == !=               | Binary logical equality operators     | Any                                 |
||| | ==? !=?             | Binary wildcard equality operators    | Integral                            |
||| | ++ --               | Unary increment, decrement operators  | Integral, real, shortreal           |
||| | inside              | Binary set membership operator        | Singular for the left operand       |
||| | dist                | Binary distribution operator          | Integral                            |
||| | {} {{}}             | Concatenation, replication operators  | Integral                            |
||| | {<<{}} {>>{}}       | Stream operators                      | Integral                            |

[L3odr0id]

Also if we don't need to get the exact SVType as a result of an expression, we can define the type of the expression (and operand) like this:

public export
data DataType = Any' | Integral' | Real' -- Real' = Real + ShortReal

[L3odr0id]

I'm not sure that an unpacked array can be an integral type. IEEE says

||| 6.11.1 Integral types
|||
||| The term integral is used throughout this standard to refer to the data types that can represent a single basic
||| integer data type, packed array, packed structure, packed union, or enum.

I would use VarOrPacked to filter values of packed types

[L3odr0id]

Does this ports list represent connections outside the context of the expression?

[L3odr0id]

@buzden

@L3odr0id, I' d like to hear your optinion on:

• how proposed expressions are modelled;

Actually I think they are too explicit. I suggest making the expressions declarations more abstract. But this should be discussed further to find the most useful implementation

• whether or not proposed expressions are usable in your part of the model;
• this proposition contains some notion of type compatibility; is it correct and how does it correspond to the notion of port assignability in your part of the model; whether they should be harmonised?

It seems that expressions take a PortsList as input. We can easily pass the connection types from the context into these expressions. This means these expressions are fully compatible with my part of the model. Although It's not clear to me how to resolve names of these ports in the printer.

Also, I like that this PR adds decEq. I’ve been avoiding it for months 😅

[GlebChili]

Consider using Fin lists instead of ListOfPortsIndices for better support of pretty printers.