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Old 23 August 2018, 19:36   #188
ross
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Join Date: Mar 2017
Location: Crossing the Rubicon
Age: 49
Posts: 2,187
Quote:
Originally Posted by meynaf View Post
- a scrambler for bytes position
Move to/from register parts ?
Yes, this suffice. Possibly extended to [ea]

Quote:
- a bits.x 'flipper', for fast mirror effect
Like coldfire's bitrev instruction, but extended to all 3 sizes ?
Yes!

Quote:
- some simple form of bitfield instruction
Reverse mode added to bitfields, for counting like btst ?
This or some simple nibble operation..

Quote:
- ALU instructions with saturation
Like convert longword to signed/unsigned byte or word ?
https://en.wikipedia.org/wiki/Saturation_arithmetic
ADDS can suffice

Quote:
- cmove
Hmm... The only one i don't see the point.
After all, it's just a branch around a move...
The point is that there is no branch! (a really slow operation..).
Often you want to insert a value into a variable only to a specific condition.
With CMOVE you can without branch
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