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How to implement saturation instructions in ARMv8 architecture?

Natesh Raina

Is there a way to write an equivalent of 32-bit saturation instruction such  as QADD or QSUB without using neon saturation instructions for Armv8 architecture?  

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    It should be do-able in C. QADD saturates to the signed integer range -2^31 to (2^31) - 1.

    You can do a regular add and then check that the result. If the result is less than -2^31 or more than (2^31) - 1 you know saturation has occurred (and you can force the result to that value.)

    Stackoverflow has a few posts on the various flavours of singed/unsigned saturating maths you can do, usually with portable C examples.
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    It should be do-able in C. QADD saturates to the signed integer range -2^31 to (2^31) - 1.

    You can do a regular add and then check that the result. If the result is less than -2^31 or more than (2^31) - 1 you know saturation has occurred (and you can force the result to that value.)

    Stackoverflow has a few posts on the various flavours of singed/unsigned saturating maths you can do, usually with portable C examples.
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