ARM VERSION 1.2 - Manual (Page 104)

Assembler Reference
3-26 Copyright © 2000, 2001 ARM Limited. All rights reserved. ARM DUI 0068B
3.6.10 Unary operators
Unary operators have the highest precedence and are evaluated first. A unary operator
precedes its operand. Adjacent operators are evaluated from right to left.
Table 3-4 lists the unary operators.
Table 3-4 Unary operators
Operator Usage Description
? ?A Number of bytes of executable code generated by line defining symbol A.
BASE :BASE:A If A is a pc-relative or register-relative expression, BASE returns the number
of its register component
BASE is most useful in macros.
INDEX :INDEX:A If A is a register-relative expression, INDEX returns the offset from that base
register.
INDEX is most useful in macros.
+ and - +A
-A
Unary plus. Unary minus. + and – can act on numeric and program-relative
expressions.
LEN :LEN:A Length of string A.
CHR :CHR:A One-character string, ASCII code A.
STR :STR:A Hexadecimal string of A.
STR returns an eight-digit hexadecimal string corresponding to a numeric
expression, or the string "T" or "F" if used on a logical expression.
NOT :NOT:A Bitwise complement of A.
LNOT :LNOT:A Logical complement of A.
DEF :DEF:A { TRUE } if A is defined, otherwise { FALSE }.
SB_OFFSET_19_12 : SB_OFFSET_19_12: label Bits[19:12] of ( label – sb). See Example of use of :SB_OFFSET_19_12:
and :SB_OFFSET_11_ 0 on page 3-27
SB_OFFSET_11_0 : SB_OFFSET_11_0 : label Least-significant 12 bytes of ( label – sb).