Fujitsu MB91191 Home Theater Server User Manual


 
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The RP to be referred by the RET:D command will not be effected even if the command within the delay
slot updates the RP.
[example]
RET:D ; Branch to address defined beforehand in RP
MOV R8, RP ; No effect on the return operation
...
The flag referred by the Bcc: Drel command is not effected by the delay slot command either.
[example]
ADD #1, R0 ; Flag change
BC:D Overflow ; Branch to execution result of above instruction
ANDCCR #0 ; Do not refer to this flag update in the above-mentioned branch instruction.
...
When RP is referred to for the command within the delay slot under the CALL:D command, the updated
contents will be read by the CALL:D command.
[example]
CALL:D Label ; Update RP and branch
MOV RP and R0 ; RP of an execution above-mentioned CALL:D result is forwarded.
..
Limitations for Branch Command with Delay
Instruction that can be placed in the delay slot
Only commands that satisfy the following conditions can be executed within the delay slot.
1 cycle instruction.
No branch instruction.
Instruction which does not influence operation even when order changes
The "1-cycle command" is a command in which "1", "a", "b", "c", or "d" is described in the cycle number
column within the commands list.
Step trace trap
Step trace trap will not be generated between execution of the branch command with delay slot and the
delay slot.
Interrupt/NMI
No interrupt/NUM is received between execution of the branch command with delay slot and the delay slot.
Undefined instruction exception
If an undefined command exists with the delay slot, undefined command exception will not be generated.
At this time, undefined instruction operates as NOP instruction.