Analog Devices ADSP-BF53x Blackfin Reference page 318

Instruction Overview
For Loop1
LOOP loop_name LC1 ;
LOOP loop_name LC1 = Preg ;
LOOP loop_name LC1 = Preg >> 1 ; /* autoinitialize LC1 (b) */
LOOP_BEGIN loop_name ;
loop (b) */
LOOP_END loop_name ;
(b) */
/* Use any one of the LOOP syntax versions with a LOOP_BEGIN and
a LOOP_END instruction. The name of the loop ("loop_name" in the
syntax) relates the three instructions together. */
LSETUP ( pcrel5m2 , lppcrel11m2 ) LC1 ;
LSETUP ( pcrel5m2 , lppcrel11m2 ) LC1 = Preg ;
ize LC1 (b) */
LSETUP ( pcrel5m2 , lppcrel11m2 ) LC1 = Preg >> 1 ;
tialize LC1 (b) */
Syntax Terminology
: (
Preg P5–0 SP
instruction.)
: 5-bit unsigned, even,
pcrel5m2
symbolic label. The range is 4 to 30, or 2
: 11-bit unsigned, even,
lppcrel11m2
replaced by a symbolic label. The range is 4 to 2046 (0x0004 to 0x07FE),
11
or 2 –2.
: a symbolic identifier
loop_name
Instruction Length
In the syntax, comment (b) identifies 32-bit instruction length.
7-14 ADSP-BF53x/BF56x Blackfin Processor Programming Reference
/* (b) */
/* define the first instruction of the
/* define the last instruction of the loop
and are not allowed as the source register for this
FP
PC
/* autoinitialize LC1 (b) */
/* (b) */
-relative offset; can be replaced by a
5
–2.
-relative offset for a loop; can be
PC
/* autoinitial-
/* autoini-