jmky Posts - Answer Overflow

jmky

•Created by jmky on 10/7/2024 in #questions

Is there a disdain for Rust from the Mojo team?

I read Chris' proposal on naming of provenance. I don't understand why can't we just adopt Rust's convention of using &'a T and &'a mut T instead of going one round of inventing new keywords ref[lifetime] and refmut[lifetime]. Mojo is unique on its own: 1) It does ASAP destructors. 2) It provides APIs to low level MLIR artefacts. There is really, in my humble opinion, NO NEED to be 'different' in areas where it won't make a huge difference. And also, why is there a subtle leaning on implementing features that are more closely associated to C++ (i.e. __copyinit__, a.k.a. copy ctor, etc), whereas there is an aversion to associate itself with Rust? Rust has done many things right, in terms of provenance tracking, quality of life enhancements, ergonomics and beautiful syntaxes. Even a 'safe' version of C++ has no-shame 'copying' Rust features, why should Mojo be ascribed to this aversion?

23 replies

MModular

•Created by jmky on 3/29/2024 in #questions

Using custom bitwidth MLIR integers.

Hi If we were to create custom types that wrap around custom bitwidth integers using MLIR types and operations, does it improve performance? Theoretically, it should not right? Because if the register is 64 bits wide, it would be a waste to use only 4 bits to store a ui4 wasting the entire 60 bits. Unless, the compiler is smart enough to look at the function signature and then group many e.g UInt[4] together.

1 replies

MModular

•Created by jmky on 2/16/2024 in #questions

Conditional typing of fields.

Suppose I have the following struct: (in pseudo Mojo)

struct IntWrapper[N: Int]:
    @parameter
    if N <= 255:
        var inner: UInt8
    else:
        var inner: Int

struct IntWrapper[N: Int]:
    @parameter
    if N <= 255:
        var inner: UInt8
    else:
        var inner: Int

For usecases where I know that it is definite that the field inner cannot hold values larger than N, then is it possible to type the fields conditionally? You can do this easily in C++, impossible to do in Rust. What about Mojo?

6 replies

MModular

•Created by jmky on 11/13/2023 in #questions

A Guide on the Translation from MLIR Syntax to Mojo Syntax

The Mojo documentation states that all MLIR operations and types can be interfaced through Mojo. However, is there a guide to translate the syntaxes of MLIR dialects into Mojo syntaxes so that engineers can take more direct control on how to use MLIR operations within Mojo?

7 replies

MModular

•Created by jmky on 10/17/2023 in #questions

How to trigger `cf.assert` MLIR operations?

Suppose I have

let _ = __mlir_op.`cf.assert`[msg=__mlir_attr.`"ERROR"`](false)

let _ = __mlir_op.`cf.assert`[msg=__mlir_attr.`"ERROR"`](false)

The error is that it cannot infer the return type of the MLIR operation. How do I resolve it? Thank you.

3 replies

MModular

•Created by jmky on 10/7/2023 in #questions

Const generics, a runtime or compile time construct?

https://docs.modular.com/mojo/changelog.html#v0.4.0-2023-10-05 Really happy to see this development in Mojo, where StringLiteral is a const generic of type 'string', which is something not even C++ or Rust manages to do. However, I am curious if the 'instantiation' or 'specialization' of the template parameter is actually resolved during runtime or compile time. I am asking because I am waiting to be able to check the length of an input ListLiteral at compile time and do comparison with it. https://github.com/jymchng/funjo/blob/master/src/array/array.mojo#L27 #mojo

2 replies

Gaming

Programming