Analog Devices ADSP-BF53x Blackfin, Reference

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ADSP-BF53x/BF56x Blackfin Processor Programming Reference 1-9
Introduction
This manual shows register names and instruction keywords in examples
using lower case. Otherwise, in explanations and descriptions, this manual
uses upper case to help the register names and keywords stand out among
text.
Free Format
Assembler input is free format, and may appear anywhere on the line. One
instruction may extend across multiple lines, or more than one instruction
may appear on the same line. White space (space, tab, comments, or new-
line) may appear anywhere between tokens. A token must not have
embedded spaces. Tokens include numbers, register names, keywords,
user identifiers, and also some multicharacter special symbols like “
+=
”,
“
/*
”, or “
||
”.
Instruction Delimiting
A semicolon must terminate every instruction. Several instructions can be
placed together on a single line at the programmer’s discretion, provided
each instruction ends with a semicolon.
Each complete instruction must end with a semicolon. Sometimes, a com-
plete instruction will consist of more than one operation. There are two
cases where this occurs.
• Two general operations are combined. Normally a comma sepa-
rates the different parts, as in
a0 = r3.h * r2.l , a1 = r3.l * r2.h ;
• A general instruction is combined with one or two memory refer-
ences for joint issue. The latter portions are set off by a “
||
” token.
For example,
a0 = r3.h * r2.l || r1 = [p3++] || r4 = [i2++] ;