Instruction Overview
8-12
ADSP-BF53x/BF56x Blackfin Processor Programming Reference
Options
The Load Data Register instruction supports the following options.
• Post-increment the source pointer by 4 bytes to maintain word
alignment.
• Post-decrement the source pointer by 4 bytes to maintain word
alignment.
• Offset the source pointer with a small (6-bit), word-aligned (multi-
ple of 4), unsigned constant.
• Offset the source pointer with a large (18-bit), word-aligned (mul-
tiple of 4), signed constant.
• Frame Pointer (
FP
) relative and offset with a 7-bit, word-aligned
(multiple of 4), negative constant.
The indexed
FP
-relative form is typically used to access local variables in a
subroutine or function. Positive offsets relative to
FP
(useful to access
arguments from a called function) can be accomplished using one of the
other versions of this instruction.
Preg
includes the Frame Pointer and
Stack Pointer.
Indirect and Post-Increment Index Addressing
The syntax of the form:
Dest
= [
Src_1
++
Src_2
]
is indirect, post-increment index addressing. The form is shorthand for
the following sequence.
Dest
= [
Src_1
] ;
/* load the 32-bit destination, indirect*/
Src_1
+=
Src_2
;
/* post-increment Src_1 by a quantity indexed
by Src_2 */
Summary of Contents for ADSP-BF53x Blackfin
Page 38: ...Conventions xxxviii ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 134: ...System Reset and Powerup 3 18 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 324: ...Instruction Overview 7 20 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 486: ...Instruction Overview 13 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 512: ...Instruction Overview 14 26 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 604: ...Instruction Overview 15 92 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 688: ...Instruction Overview 18 48 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 742: ...Instruction Overview 19 54 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 752: ...Examples 20 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 790: ...ADSP BF535 Flags A 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 800: ...Performance Monitor Registers B 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Page 1042: ...Index I 40 ADSP BF53x BF56x Blackfin Processor Programming Reference...