Texas Instruments TMS320C3x - Manual (Page 194)

Delayed Branches
7-10
Example 7–6. Incorrectly Placed Delayed Branches
B1: BD L1
NOP
NOP
B2: B L2 ; This branch is incorrectly placed.
NOP
NOP
NOP
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For faster execution, it might still be advantageous to use a delayed branch
followed by NOP instructions by trading increased program size for faster
speed. This is shown in Example 7–7 where a NOP takes the place of the third
unused instruction after the delayed branch.
Example 7–7. Delayed Branch Execution
* TITLE DELAYED BRANCH EXECUTION
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LDF* +AR1(5),R2
; Load contents of memory to R2
BGED SKIP ; If loaded number >=0, branch
; (delayed)
LDFN R2,R1 ; If loaded number <0, load it to R1
SUBF 3.0,R1 ; Subtract 3 from R1
NOP ; Dummy operation to complete delayed
; branch
MPYF 1.5,R1 ; Continue here if loaded number <0
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SKIP LDF R1,R3 ; Continue here if loaded number >=0