Programming with 64-Bit ARM Assembly Language: Single Board Computer Development for Raspberry Pi and Mobile Devices

© Stephen Smith 2020

S. SmithProgramming with 64-Bit ARM Assembly Languagehttps://doi.org/10.1007/978-1-4842-5881-1_11

11. Multiply, Divide, and Accumulate

Stephen Smith¹ 

(1)

Gibsons, BC, Canada

 

In this chapter, we return to using mathematics. We’ve already covered addition, subtraction, and a collection of bit operations on our 64-bit registers. Now, we will learn multiplication and division.

We will program multiply with accumulate instructions. But first of all, we will provide some background on why the ARM processor has so much circuitry dedicated to performing this operation. This will get us into the mechanics of vector and matrix multiplication.

Multiplication

The multiply instruction is

MUL Xd, Xn, Xm

This instruction computes Xd = Xn ∗ Xm. Looks ...