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ADSP-BF53x/BF56x Blackfin Processor Programming Reference
JUMP mylabel ;
/* skip any code placed here */
mylabel:
/* continue to fetch and execute instruction here */
Direct Call
The
CALL
instruction is a branch instruction that copies the address of the
instruction which would have executed next (had the
CALL
instruction not
executed) into the
RETS
register. The direct
CALL
instruction has a 25-bit,
PC-relative offset that must be a multiple of two (bit 0 must be a 0). The
25-bit value gives an effective dynamic range of –16,777,216 to
+16,777,214 bytes. A direct
CALL
instruction is always a 4-byte
instruction.
Indirect Branch and Call
The indirect
JUMP
and
CALL
instructions get their destination address from
a data address generator (DAG) P-register. For the
CALL
instruction, the
RETS
register is loaded with the address of the instruction which would
have executed next in the absence of the
CALL
instruction.
For example:
JUMP (P3) ;
CALL (P0) ;
To load a P-register with a symbolic target label you may use one of the
following syntax styles. The syntax may differ in various assembly tools
sets.
Modern style:
P4.H = HI(mytarget);
P4.L = LO(mytarget);
JUMP (P4);
Содержание ADSP-BF53x Blackfin
Страница 38: ...Conventions xxxviii ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 134: ...System Reset and Powerup 3 18 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 324: ...Instruction Overview 7 20 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 486: ...Instruction Overview 13 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 512: ...Instruction Overview 14 26 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 604: ...Instruction Overview 15 92 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 688: ...Instruction Overview 18 48 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 742: ...Instruction Overview 19 54 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 752: ...Examples 20 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 780: ...Product Identification Register 21 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 790: ...ADSP BF535 Flags A 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 800: ...Performance Monitor Registers B 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 994: ...Instructions Listed By Operation Code C 194 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 1042: ...Index I 40 ADSP BF53x BF56x Blackfin Processor Programming Reference...