7 logical expressions, 8 logical literals, Logical expressions – ARM VERSION 1.2 User Manual

Page 101

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Assembler Reference

ARM DUI 0068B

Copyright © 2000, 2001 ARM Limited. All rights reserved.

3-23

3.6.6

Register-relative and program-relative expressions

A register-relative expression evaluates to a named register plus or minus a numeric
constant (see MAP on page 7-15).

A program-relative expression evaluates to the program counter (pc), plus or minus a
numeric constant. It is normally a label combined with a numeric expression.

Example

LDR r4,=data+4*n ; n is an assembly-time variable
; code
MOV pc,lr
data DCD value0
; n-1 DCD directives
DCD valuen ; data+4*n points here
; more DCD directives

3.6.7

Logical expressions

Logical expressions consist of combinations of logical literals (

{TRUE}

or

{FALSE}

),

logical variables, Boolean operators, relations, and parentheses (see Boolean operators
on page 3-31
).

Relations consist of combinations of variables, literals, constants, or expressions with
appropriate relational operators (see Relational operators on page 3-30).

3.6.8

Logical literals

There are only two logical literals:

{TRUE}

{FALSE}

.

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