Freescale Semiconductor SC140 Rule G.P.3, Rule G.P.4, Rule G.P.5, Example 7-19. RTE Uses Both AAU

Models: SC140

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Static Programming Rules

Rule G.P.3

The following instructions in each line are mutually exclusive, and cannot be grouped in a VLES. For mutually exclusive IFc subgroups in a VLES, this rule applies independently to each subgroup.

MARK

DEBUG and DEBUGEV

DI and EI

BREAK, CONT, CONTD, DOENn, DOENSHn, and SKIPLS

STOP, WAIT, and any COF instruction cannot be grouped in a VLES. This applies also to a VLES having two mutually exclusive IFc subgroups.

Example 7-18. VLES Has Mutually Exclusive Instructions

stop

wait

;not allowed

mark

mark

;not allowed

stop

mark

;allowed

ift doen1 #5 iff doen2 #4

;allowed

ift debug

iff debugev

;allowed

ift stop

iff wait

;not allowed

ift wait

iff bra _label

;not allowed

Rule G.P.4

An RTE/D instruction cannot be:

Grouped in a VLES with another AGU instruction.

In a VLES having two IFc subgroups.

Example 7-19. RTE Uses Both AAU

rted

inca r3

;not allowed

ift clr d0

ifa rte

;not allowed - two IFc subgroups

ift rte

impy d0,d1,d2

;allowed - one IFc group

Rule G.P.5

The same Nn or Mn register can be used as a data source operand of a MOVE-like instruction only once in a VLES. For mutually exclusive IFc subgroups in a VLES, this rule applies independently to each subgroup.

SC140 DSP Core Reference Manual

7-13

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Freescale Semiconductor SC140 Rule G.P.3, Rule G.P.4, Rule G.P.5, Example 7-18. Vles Has Mutually Exclusive Instructions