Raph Levien raphlinus

## gist:5aca9de53f9d6b24933cb24d8a60df63
1	s_version 0x4004                                                                               	4	0.01	2
2	s_inst_prefetch 0x3                                                                            	4	0.01	1
3	s_getpc_b64 s[0:1]                                                                             	4	0.03	5
4	s_mov_b32 s0, s2                                                                               	4	0.05	9
5	s_load_dwordx4 s[4:7], s[0:1], null                                                            	4	0.01	1
6	s_load_dwordx4 s[12:15], s[0:1], 0x20                                                          	4	0.01	1
7	s_load_dwordx4 s[16:19], s[0:1], 0x40                                                          	4	0.01	1
8	v_lshl_add_u32 v3, s8, 8, v0                                                                   	4	0.03	5
9	v_lshrrev_b32_e32 v0, 2, v3                                                                    	4	0.01	1
10	s_waitcnt lgkmcnt(0)

## relaxed.rs
use std::sync::atomic::Ordering;

use loom::{
    sync::{atomic::AtomicU32, Arc},
    thread,
};

#[test]
fn relaxed() {
    loom::model(|| {

## main.rs
// SPDX-License-Identifier: MIT
use proptest::test_runner::TestRunner;
use proptest::strategy::{Strategy, ValueTree};

fn main() {
    let email_re = "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\
    (?:\\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$";
    let re = regex::Regex::new(email_re).unwrap();
    let mut runner = TestRunner::default();
    for _ in 0..100_000_000 {

## max.hlsl
ByteAddressBuffer input;
RWByteAddressBuffer output;

groupshared uint max_value;

[numthreads(256, 1, 1)]
void main(uint index: SV_GroupIndex) {
    if (index == 0) {
        max_value = 0;
    }

## simplify_svg.rs
// Adapted from code provided by @rachael-wang

use std::{env, fs};

fn main() {
    let args: Vec<String> = env::args().collect();

    let svg_contents = fs::read_to_string(&args[1]).unwrap();
    let curve = kurbo::BezPath::from_svg(&svg_contents).expect("SVG parse error");

## subgroup.md

      
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                raphlinus
                / subgroup.md
            
            
              Last active
              March 10, 2023 23:00
            
              
                Draft subgroup issue for gpuweb
              
          
    Considerations for subgroups

One feature that is clearly out of scope for WebGPU 1.0 but is desired for the near future is subgroups. It is a way to move data between threads within a workgroup with less overhead and latency than workgroup shared memory, but poses more challenges for portability. While almost all modern GPU hardware supports subgroup operations, the feature poses significant compatibility challenges. In particular, while workgroup size is determined by the programmer within generous ranges (WebGPU requires a minimum maximum of 256), subgroup sizes vary by hardware and also compiler heuristics. Shaders need be written in a way that adapts to a wide range of subgroup sizes, which is quite challenging.
This issue will be written largely from the perspective of accelerating prefix sum operations (an important primitive within Vello), but there are many potential applications. One relatively recent development is cooperative matrix operations, which are supported in most newer GPU hardware a

  
## xcode_crash_log.txt
-------------------------------------
Translated Report (Full Report Below)
-------------------------------------

Process:               Xcode [50519]
Path:                  /Applications/Xcode.app/Contents/MacOS/Xcode
Identifier:            com.apple.dt.Xcode
Version:               14.2 (21534)
Build Info:            IDEFrameworks-21534000000000000~49 (14C18)
App Item ID:           497799835

## barrier_test.swift
import Foundation
import Metal

// This is translated by naga from tile_alloc.wgsl
// naga --buffer-bounds-check-policy ReadZeroSkipWrite tile_alloc.wgsl tile_alloc.metal
let metalProgram = """
// language: metal2.0
#include <metal_stdlib>
#include <simd/simd.h>

## barrier_test.wgsl

@group(0) @binding(0)
var<storage, read_write> bump: atomic<u32>;

@group(0) @binding(1)
var<storage, read_write> paths: array<u32>;

let WG_SIZE = 256u;

var<workgroup> sh_tile_offset: u32;

## webgpu-test.html
<html>
    <body>
        <p>WebGPU test:</p>

    </body><div id="out"></div>
    <div>Expected: [1, 1, 1]</div>
    <script>
function display(text) {
    document.getElementById("out").textContent = text;
}
	1 s_version 0x4004 4 0.01 2
	2 s_inst_prefetch 0x3 4 0.01 1
	3 s_getpc_b64 s[0:1] 4 0.03 5
	4 s_mov_b32 s0, s2 4 0.05 9
	5 s_load_dwordx4 s[4:7], s[0:1], null 4 0.01 1
	6 s_load_dwordx4 s[12:15], s[0:1], 0x20 4 0.01 1
	7 s_load_dwordx4 s[16:19], s[0:1], 0x40 4 0.01 1
	8 v_lshl_add_u32 v3, s8, 8, v0 4 0.03 5
	9 v_lshrrev_b32_e32 v0, 2, v3 4 0.01 1
	10 s_waitcnt lgkmcnt(0)
	use std::sync::atomic::Ordering;

	use loom::{
	sync::{atomic::AtomicU32, Arc},
	thread,
	};

	#[test]
	fn relaxed() {
	loom::model(\|\| {
	// SPDX-License-Identifier: MIT
	use proptest::test_runner::TestRunner;
	use proptest::strategy::{Strategy, ValueTree};

	fn main() {
	let email_re = "^[a-zA-Z0-9.!#$%&'*+/=?^_`{\|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?\
	(?:\\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$";
	let re = regex::Regex::new(email_re).unwrap();
	let mut runner = TestRunner::default();
	for _ in 0..100_000_000 {
	ByteAddressBuffer input;
	RWByteAddressBuffer output;

	groupshared uint max_value;

	[numthreads(256, 1, 1)]
	void main(uint index: SV_GroupIndex) {
	if (index == 0) {
	max_value = 0;
	}
	// Adapted from code provided by @rachael-wang

	use std::{env, fs};

	fn main() {
	let args: Vec<String> = env::args().collect();

	let svg_contents = fs::read_to_string(&args[1]).unwrap();
	let curve = kurbo::BezPath::from_svg(&svg_contents).expect("SVG parse error");
	-------------------------------------
	Translated Report (Full Report Below)
	-------------------------------------

	Process: Xcode [50519]
	Path: /Applications/Xcode.app/Contents/MacOS/Xcode
	Identifier: com.apple.dt.Xcode
	Version: 14.2 (21534)
	Build Info: IDEFrameworks-21534000000000000~49 (14C18)
	App Item ID: 497799835
	import Foundation
	import Metal

	// This is translated by naga from tile_alloc.wgsl
	// naga --buffer-bounds-check-policy ReadZeroSkipWrite tile_alloc.wgsl tile_alloc.metal
	let metalProgram = """
	// language: metal2.0
	#include <metal_stdlib>
	#include <simd/simd.h>

	@group(0) @binding(0)
	var<storage, read_write> bump: atomic<u32>;

	@group(0) @binding(1)
	var<storage, read_write> paths: array<u32>;

	let WG_SIZE = 256u;

	var<workgroup> sh_tile_offset: u32;
	<html>
	<body>
	<p>WebGPU test:</p>

	</body><div id="out"></div>
	<div>Expected: [1, 1, 1]</div>
	<script>
	function display(text) {
	document.getElementById("out").textContent = text;
	}