ARM Architecture Reference Manual ARMv7-A and ARMv7-R edition

Chapter A6
Thumb Instruction Set Encoding
This chapter introduces the Thumb instruction set and describes how it uses the ARM programmers’ model.
It contains the following sections:
Thumb instruction set encoding on page A6-2
16-bit Thumb instruction encoding on page A6-6
32-bit Thumb instruction encoding on page A6-14.
For details of the differences between the Thumb and ThumbEE instruction sets see Chapter A9 ThumbEE.
Note
Architecture variant information in this chapter describes the architecture variant or extension in
which the instruction encoding was introduced into the Thumb instruction set.
In the decode tables in this chapter, an entry of - for a field value means the value of the field does
not affect the decoding.
ARM DDI 0406B Copyright © 1996-1998, 2000, 2004-2008 ARM Limited. All rights reserved. A6-1