Storm m-rots

RISC-V Vector Extension for Integer Workloads: An Informal Gap Analysis

Note: To verify my RVI membership and idenity on this otherwise semi anonymous account: I'm Olaf Bernstein, you should be able to view my sig-vector profile, if you are a member of the vector SIG.

The goal of this document is to explore gaps in the current RISC-V Vector extensions (standard V, Zvbb, Zvbc, Zvkg, Zvkn, Zvks), and suggest instructions to fill these gaps. My focus lies on application class processors, with the expectation that suggested instructions would be suitable to become mandatory or optional instructions in future profiles.

I'll assume you are already familiar with RVV, if not, here is a great introduction and here the latest RISC-V ISA manual.

Reliable mouseEnter/Exit for SwiftUI

On Mac, SwiftUI's .onHover closure is not always called on mouse exit, particularly with high cursor velocity. A grid of targets or with finer target shapes will often have multiple targets falsely active after the mouse has moved on.

It is easy to run back to AppKit's safety. Below is a SwiftUI-like modifier for reliable mouse-tracking. You can easily adapt it for other mouse tracking needs.

import SwiftUI

NDJSON is a convenient format for storing or streaming structured data that may be processed one record at a time.

Each line is a valid JSON value
Line separator is ‘\n’

1. Convert JSON to NDJSON?

cat test.json | jq -c '.[]' > testNDJSON.json

How to Generate & Use Private Keys using OpenSSL's Command Line Tool

These commands generate and use private keys in unencrypted binary (not Base64 “PEM”) PKCS#8 format. The PKCS#8 format is used here because it is the most interoperable format when dealing with software that isn't based on OpenSSL.

OpenSSL has a variety of commands that can be used to operate on private key files, some of which are specific to RSA (e.g. openssl rsa and openssl genrsa) or which have other limitations. Here we always use

	import SwiftUI
	import UIKit

	public final class HostingView: UIView {
	public init(@ViewBuilder content: () -> some View) {
	super.init(frame: .zero)

	let contentView = UIHostingConfiguration(content: content)
	.margins(.all, 0)
	.makeContentView()

	uint64_t neonmovemask_bulk(uint8x16_t p0, uint8x16_t p1, uint8x16_t p2, uint8x16_t p3) {
	const uint8x16_t bitmask1 = { 0x01, 0x10, 0x01, 0x10, 0x01, 0x10, 0x01, 0x10,
	0x01, 0x10, 0x01, 0x10, 0x01, 0x10, 0x01, 0x10};
	const uint8x16_t bitmask2 = { 0x02, 0x20, 0x02, 0x20, 0x02, 0x20, 0x02, 0x20,
	0x02, 0x20, 0x02, 0x20, 0x02, 0x20, 0x02, 0x20};
	const uint8x16_t bitmask3 = { 0x04, 0x40, 0x04, 0x40, 0x04, 0x40, 0x04, 0x40,
	0x04, 0x40, 0x04, 0x40, 0x04, 0x40, 0x04, 0x40};
	const uint8x16_t bitmask4 = { 0x08, 0x80, 0x08, 0x80, 0x08, 0x80, 0x08, 0x80,
	0x08, 0x80, 0x08, 0x80, 0x08, 0x80, 0x08, 0x80};

	uint64_t neonmovemask_bulk(uint8x16_t p0, uint8x16_t p1, uint8x16_t p2, uint8x16_t p3) {
	const uint8x16_t bitmask = { 0x01, 0x02, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80,
	0x01, 0x02, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80};
	uint8x16_t t0 = vandq_u8(p0, bitmask);
	uint8x16_t t1 = vandq_u8(p1, bitmask);
	uint8x16_t t2 = vandq_u8(p2, bitmask);
	uint8x16_t t3 = vandq_u8(p3, bitmask);
	uint8x16_t sum0 = vpaddq_u8(t0, t1);
	uint8x16_t sum1 = vpaddq_u8(t2, t3);
	sum0 = vpaddq_u8(sum0, sum1);