Texas Instruments TMS320C28x Reference Manual page 404

Example
; Negate the contents of the 64-bit Var64 and saturate:
MOVL
MOVL
SETC
NEG64 ACC:P
MOVL
MOVL
ACC,@Var64+2
P,@Var64+0
OVM
@Var64+2,ACC
@Var64+0,P
; Load ACC with high 32-bits of Var64
; Load P with low 32-bits of Var64
; Enable overflow mode (saturate)
; Negate ACC:P with saturation
; Store high 32-bit result into Var64
; Store low 32-bit result into Var64
NEG64 ACC:P
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