MTCannon: Increase differential test coverage across opcodes

[mbaxter]

Description

Increase differential test coverage across MIPS opcodes. We have some basic coverage with the existing open mips tests, but we should try to get more coverage around edge cases. Look into adding more tests and porting existing tests from MIPS.t.sol.

New tests should follow the single-step unit test pattern as in this example, rather than adding more assembly tests. The list of supported instructions is available in the README. Documentation on MIPS instructions can be found here.

[GrapeBaBa]

@mbaxter I see a series of issues related to cannon testing. Are these issues already in development, and are they suitable for external contributors like us to contribute?

[mbaxter]

@GrapeBaBa - no one is assigned to this yet, so happy to have external contributors take a look! Let me know if you have any questions.

[Inphi]

@GrapeBaBa would you be able to take on this issue?

[GrapeBaBa]

@GrapeBaBa would you be able to take on this issue?

Yes

[GrapeBaBa]

• add/addi/addu/addiu test
• sub/subu/and/andi/or/ori/xor/xori/nor/slt/sltu tests
• lb/lh/lw/lbu/lhu/lwl/lwr/sb/sh/swl/sw/swr tests
• movz/movn tests
• movf/movt tests
• mul/div opcodes tests

[Inphi]

Looks like this is done. Thanks!

[GrapeBaBa]

Looks like this is done. Thanks!

@Inphi I think it is still a lot of tests need to port, I plan to use this task tracking all the sub tasks, can you reopen it?

[Inphi]

Ah right. Sorry about that.

[mbaxter]

@GrapeBaBa - just noticed that the new LoadStore tests fell through the cracks wrt the 64-bit refactor. Would you mind updating these to use the new Word architecture-specific variables?

[GrapeBaBa]

@GrapeBaBa - just noticed that the new LoadStore tests fell through the cracks wrt the 64-bit refactor. Would you mind updating these to use the new Word architecture-specific variables?

Ok, will do it.

[Inphi]

@GrapeBaBa Are we good to close out this ticket?

[GrapeBaBa]

There are still a few tests that need to be migrated. If it's not necessary, I suggest not closing it for now.

[Inphi]

Gotcha. Let's keep this issue open then. The remaining instruction tests to be migrated are:

• - jalr
• - lui
• - srav
• - sll
• - srl
• - clz
• - clo
• - srlv
• - bgtz
• - bne
• - beq
• - jump

Feel free to create sub-issues for these as needed.

[BlocksOnAChain]

@GrapeBaBa - hey, wanted to check about your plans to continue work on this issue, since it would be great to close the remaining work?

[GrapeBaBa]

should be finished this weekend