2 vles-based cof rules, Vles-based cof rules -45 – Freescale Semiconductor StarCore SC140 User Manual

Page 295

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Dynamic Programming Rules

SC140 DSP Core Reference Manual

7-45

7.6.5.2 VLES-Based COF Rules

VLES-based COF rules are detected like static rules, except the rule is detected from the simulation trace,
not the source code order. A VLES having a COF instruction is counted like any other VLES. Exceptions
to the above are JSR/D and BSR/D instructions, guaranteeing an inherent one VLES distance between the
instructions in the source execution flow (including the delay slot), and the instructions in the destination
flow.

The relevant VLES-based rules that the simulator detects across COF boundaries are:

Non-loop COF rules

— T.1

— SR.2

— SR.4

Loop COF rules

— L.L.5

— L.L.6

— L.D.1

— L.D.2

— L.D.3

— L.D.5

— L.D.6

— L.D.7

— L.D.8

— L.D.9

— L.C.10

— L.G.3

— L.G.4

Example 7-84. Set condition during a COF, and use it at the destination (T.1)

bt _des1cmpeq d0,d1
...

_des1 ift tfra r0,r1

;Not allowed

btd _des2cmpeq d0,d1
nop
...

_des2 ift tfra r0,r1

; Allowed

bt _des3
cmpeq d0,d1
...

_des3 ift tfra r0,r1

; Not allowed

jsrd _des4
cmpeq d0,d1
...

_des4 ift tfra r0,r1

; Allowed (1 extra VLES calculated between cmpeq and

ift)

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