Member Avatar for nuliknol

Hi,
is there a way to do 128 bit comparison in one instruction with SSE 4.2a?
I need to compare if the XMM0 register is 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
If not, what would be the fastest way to compare with two steps of 64bit comparisions?

Thanks in advance.

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  • Latest Post Latest Post by untio
Member Avatar for Narue

is there a way to do 128 bit comparison in one instruction with SSE 4.2a?

No.

If not, what would be the fastest way to compare with two steps of 64bit comparisions?

Compare the high quadword, then the low quadword if the high quadwords are equal.

Member Avatar for untio

Hi,
You can use: CMPEQPS
And to test if the result is all ones or zeros: MOVMSKPS.
I hope that this can be useful.

Please, forgive me. I have not read the number version of sse in the post.

Edited by untio because: n/a
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