Matt Chaput mchaput

Foreward

This document was originally written several years ago. At the time I was working as an execution core verification engineer at Arm. The following points are coloured heavily by working in and around the execution cores of various processors. Apply a pinch of salt; points contain varying degrees of opinion.

It is still my opinion that RISC-V could be much better designed; though I will also say that if I was building a 32 or 64-bit CPU today I'd likely implement the architecture to benefit from the existing tooling.

Mostly based upon the RISC-V ISA spec v2.0. Some updates have been made for v2.2

Original Foreword: Some Opinion

The RISC-V ISA has pursued minimalism to a fault. There is a large emphasis on minimizing instruction count, normalizing encoding, etc. This pursuit of minimalism has resulted in false orthogonalities (such as reusing the same instruction for branches, calls and returns) and a requirement for superfluous instructions which impacts code density both in terms of size and

	import QtQuick
	import QtQuick.Controls
	import Qt.labs.platform as Labs

	ApplicationWindow {
	id: root
	width: 640
	height: 64
	visible: true
	Rectangle {

	import os.path
	import sqlite3 as sqlite
	from sqlite3 import Binary

	from whoosh.kv.db import Database, DBReader, DBWriter, Cursor
	from whoosh.kv.db import OverrunError, ReadOnlyError


	class Sqlite(Database):
	default_table = "kv"

	from whoosh import index, fields
	from whoosh import qparser


	# Fake data from external files
	files = [
	(u"t1.txt", u"Earth is a beautiful planet.Earth is the third planet from the Sun. It is the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets. It is sometimes referred to as the world or the Blue Planet."),
	(u"t2.txt", u"jupiter is the biggest planet."),
	(u"t3.txt", u"earth is known as blue planet."),
	(u"t4.txt", u"earth is the 3rd most planet in the universe."),