Static Programming Rules

Rule T.2.a

At least one VLES is required between an ISAP instruction that affects the T status bit in SR and a conditional COF instruction.

Example 7-40. T Bit Update by ISAP and COF

{tsteq k0}

; tsteq is an ISAP instruction that

jt r0

updates the T bit

; not allowed

{tsteq k0}

 

nop

; allowed

jf _destination

 

 

Rule T.2.b

At least two VLES are required between an ISAP instruction that affects the T status bit in SR and a MOVET/MOVEF instruction.

Example 7-41. T Bit Update by ISAP and MOVET/MOVEF

{tsteq k0}

; tsteq is an ISAP instruction that

movet r0,r1

updates the T bit

; not allowed

{tsteq k0}

 

nop

 

nop

; allowed

movet r1,r2

 

 

Rule T.2.c

At least two VLES are required between an ISAP instruction that affects the T status bit in SR and an AGU instruction in an IFT/IFF group or subgroup. This rule does not apply to AGU instructions in an IFA subgroup.

Example 7-42. T Bit Update by ISAP and IFT/IFF

{tsteq k0}

; tsteq is an ISAP instruction that

ift move.l d0,d1

updates the T bit

; not allowed

{tsteq k0}

 

nop

 

nop

; allowed

ift move.l d1,d2

 

 

Rule SR.2

At least two VLES are required between a MOVE-like instruction that writes the SR register and an instruction affected by a status bit in SR.

SC140 DSP Core Reference Manual

7-23

Page 273
Image 273
Freescale Semiconductor SC140 specifications Rule T.2.a, Rule T.2.b, Rule T.2.c, Rule SR.2