Inline SSE intrinsic _mm_setones_si128 ?

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C++

SSE

intrinsics

The SSE intrinsic _mm_setzero_si128 is very handy to initialize a register with all zeroes and it translates to the single PXOR opcode taking twice the same register. It is the only SSE intrinsic taking no argument.

The similar _mm_setones_si128 intrinsic would be equivalently handy to initialize a register to all ones and it could translate to the single PCMPEQB opcode.

Unfortunately, this intrinsic does not exist and it is problematic to emulate it with _mm_cmpeq_epi8: code like

__m128i AllOnes= _mm_cmpeq_epi8(AllOnes, AllOnes);

raises an unintialized variable warning at compile-time, and worse, raises a condition at run-time in a debug build.

Alternatives are to first initialize the variable with _mm_setzero_si128, use one of the _mm_set_epi... intrinsics or apply _mm_cmpeq_epi8 to another variable. None of these options please me as they will not translate to a single opcode.

Can I work around this by clever tricks ?
Can I hack some compiler files to achieve this effect ?
Can I contact the right person in the MSVC Developers Team to let them add this trivial but useful feature ?