raphlinus

@compute @workgroup_size(256)
fn main(@builtin(local_invocation_id) local_id: vec3<u32>) {
    if local_id.x < 5u {
        workgroupBarrier();
    }
}

raphlinus

struct Alloc {
  offset : u32,
}

struct BinInstanceRef {
  offset : u32,
}

struct BinInstance {

raphlinus

V: A post-truth language project

This is ordinarily something I'd write on my blog, and I might still, but I'm feeling cautious for reasons that will become clear.

It's often said that we live in a "post-truth" society. This is usually said in the context of politics, fake reviews, etc., and is adjacent to discussions of disinformation, also often connected to the threat of deepfakes and the potential of large language models to produce persuasive text. Even in science there is a replication crisis, and a disturbing amount of straight-up fraud, as documented by Dr. Elisabeth Bik and friends. But it's far more unusual for a programming language to be so characterized. Meet V.

The programming language space is known for passionate discussions which often come down to values, because the space is one of tradeoffs. Want safety (which I believe is related to religious-like concepts of purity and contamination)? Sure, but you have to decide whether you're willing to give up performance

raphlinus

The not-too-clever programmer

This is a translation of grugbrain.dev into clear English. All props to the original author.

Introduction

This is a collection of thoughts on software development, originally written by an pseudonymous author styling themselves the "grug brain developer," but then translated into clear English by Raph Levien.

I am not an extremely smart developer, but I have many years of experience and have learned some things, although still don't know everything.

raphlinus

// Copyright 2022 Google LLC.
// SPDX-License-Identifier: Apache-2.0

// Scrolling test case by Raph Levien

import SwiftUI
import CryptoKit

struct ContentView: View {
    var body: some View {

raphlinus

NEWWG
NEWSG
NEWTHREAD
st.atom.scopedev.sc0 x = 2
NEWWG
NEWSG
NEWTHREAD
st.atom.scopedev.sc0 x = 1
NEWWG
NEWSG

raphlinus

NEWWG
NEWSG
NEWTHREAD
st.atom.scopedev.sc0 x = 1
NEWWG
NEWSG
NEWTHREAD
ld.atom.scopedev.sc0 x = 1
ld.scopedev.sc0 x
NOSOLUTION consistent[X] && #X.dr=0

raphlinus

Path segment encoding

The new (November 2021) element processing pipeline has a particularly clever approach to path segment encoding, and this document explains that.

By way of motivation, in the old scene encoding, all elements take a fixed amount of space, currently 36 bytes, but that's at risk of expanding if a new element type requires even more space. The new design is based on stream compaction. The input is separated into multiple streams, so in particular path segment data gets its own stream. Further, that stream can be packed.

As explained in [#119], the path stream is separated into one stream for tag bytes, and another stream for the path segment data.

Prefix sum for unpacking

raphlinus

:1:0257:0257[20554002x_00000001x] mov.s32s32 r0.z, 1
:0:0258:0258[00000500x_00000000x] (rpt5)nop
:6:0259:0264[c0260202x_02618001x] ldib.untyped.1d.u32.1.imm r0.z, r0.z, 1
:2:0260:0265[52b400f8x_20000002x] (sy)cmps.s.eq p0.x, r0.z, 0
:1:0261:0266[20044906x_000000cfx] (rpt1)mov.f32f32 r1.z, (r)r51.w
:0:0262:0268[00000300x_00000000x] (rpt3)nop
:0:0263:0272[00900000x_0000057cx] br !p0.x, #1404
:1:0264:0273[20554002x_00000002x] mov.s32s32 r0.z, 2
:1:0265:0274[20554003x_00000000x] mov.s32s32 r0.w, 0
:0:0266:0275[00000200x_00000000x] (rpt2)nop

raphlinus

Pure lasagna:

trait AppLogic {
    fn run(&mut self, actions: Vec<(Id, Box<dyn Any>)>) -> Mutation;
}

A callback based approach to the actions: