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NEON vs Intel SSE - equivalence of certain operations

Marius Cetateanu
Note: This was originally posted on 26th August 2011 at http://forums.arm.com

Hi,

I'm having some trouble figuring out the NEON equivalence of a couple of Intel SSE operations.
It seems that NEON is not capable to handle an entire Q register at once(128 bit value data type; haven't found anything in
the arm_neon header or in the reference http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0348c/Badcdfad.html).

What I want to do is the following:

// Intel SSE
// shift the entire 128 bit value with 2 bytes to the right; this is done without sign extension
// by shifting in zeros
__m128i val = _mm_srli_si128(d, 2);
// insert the least significant 16 bits of "some_16_bit_val"(the whole thing in this case)
// into the selected 16 bit integer of vector "val"(the 16 bit element with index 7 in this case)
val = _mm_insert_epi16(val, some_16_bit_val, 7);

I've looked at the shifting operations provided by NEON but could not find an equivalent way of
doing the above(I don't have much experience with NEON). Is it possible to do the above(I guess it is I just don't know how)?
Any pointers greatly appreciated.

Thanks