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Dreg: R7–0

sat_flag:
nonoptional saturation flag, (S) or (NS)

In the syntax, comment (a) identifies 16-bit
instruction length. Comment (b) identifies 32-bit instruction length.

The Negate (Two’s-Complement) instruction
returns the same magnitude with the opposite arithmetic sign. The Accumulator
versions saturate the result at 40 bits. The instruction calculates by
subtracting from zero.

The Dreg version of the Negate
(Two’s-Complement) instruction is offered with or without saturation. The only
case where the nonsaturating Negate would overflow is when the input value is
0x8000 0000. The saturating version returns 0x7FFF FFFF; the nonsaturating
version returns 0x8000 0000.

In the syntax, where sat_flag appears, substitute one of the following values.

• (S) saturate
  the result
  
• (NS) no saturation
  

See "Saturation" for a
description of saturation behavior.