10 dci – ARM VERSION 1.2 User Manual

Page 305

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Directives Reference

ARM DUI 0068B

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

7-23

7.3.10

DCI

In ARM code, the

DCI

directive allocates one or more words of memory, aligned on

4-byte boundaries, and defines the initial runtime contents of the memory.

In Thumb code, the

DCI

directive allocates one or more halfwords of memory, aligned

on 2-byte boundaries, and defines the initial runtime contents of the memory.

Syntax

{label} DCI expr{,expr}

where:

expr

is a numeric expression (see Numeric expressions on page 3-20).

Usage

The

DCI

directive is very like the

DCD

or

DCW

directives, but the location is marked as code

instead of data. Use

DCI

when writing macros for new instructions not supported by the

version of the assembler you are using.

In ARM code,

DCI

inserts up to three bytes of padding before the first defined word, if

necessary, to achieve 4-byte alignment. In Thumb code,

DCI

inserts an initial byte of

padding, if necessary, to achieve 2-byte alignment.

See also DCD and DCDU on page 7-19 and DCW and DCWU on page 7-25.

Example

MACRO ; this macro translates newinstr Rd,Rm
; to the appropriate machine code
newinst $Rd,$Rm
DCI 0xe16f0f10 :OR: ($Rd:SHL:12) :OR: $Rm
MEND

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