Draft for PseudoInstructions

[AFOliveira]

I have this format being automatically generated for all pseudo-instructions. Does this reflect the discussion we had on last week's meeting?

The corner case of conditional pseudo-instructions is not automatable.

[dhower-qc]

Thanks for doing this!

A few comments/questions:

• origin_instruction(s?) should be an array so we can support the multi-inst sequences
• Let's make the instruction reference a $ref (I think we are moving that direction universally in the db).
• Instead of capturing encoding/match, could we specify variable values of the parent instruction? I think it captures the same information but might be more informative to a reader. (not sold on this, just thinking out loud). For example:

origin_instructions:
- parent: { $ref: inst/I/add.yaml# }
  encoding:
    variables:
      rs1:
        const: 0
      rs2:
        const: 5
      rd:
        const: 0

[AFOliveira]

Thanks for the review.

• origin_instruction(s?) should be an array so we can support the multi-inst sequences

Idk about how the backend would be easier, so just asking, but if we define them as you did couldn't we just add another entry? e.g.

origin_instructions:
- parent: { $ref: inst/I/add.yaml# }
  encoding:
    variables:
      rs1:
        const: 0
      rs2:
        const: 5
      rd:
        const: 0
- parent: { $ref: inst/I/other.yaml# }
  encoding:
    variables:
      rs1:
        const: 0
      rs2:
        const: 5
      rd:
        const: 0

Let's make the instruction reference a $ref (I think we are moving that direction universally in the db).

Ok.

Instead of capturing encoding/match, could we specify variable values of the parent instruction? I think it captures the same information but might be more informative to a reader. (not sold on this, just thinking out loud).

I can do this, since it was already being done but in a different way for previous pseudoinstructions definition.

[dhower-qc]

Idk about how the backend would be easier, so just asking, but if we define them as you did couldn't we just add another entry? e.g.

Yep!