Re: Any libraries for vector mask and vector population count?

Dan wrote:
...
For those lucky enough not to have to program in CAL, S registers are
scalar, V are vector, T are transfer, A and B are data registers, This
code was originally written for a Cray-1, so it is simpler than X and
Y assembler. The code is uncommented deliberately. Sorry about that.

All it does is the same as the Fortran-90 PACK intrinsic. Just use
the intrinsic. If it isn't fast enough, complain to your compiler
vendor.

And it won't work on a Cray-1. It uses the compressed index and hardware
gather instructions. Which means mid-life X-MP, onwards.

The Cray compilers were eventually able to vectorize this idiom
automatically. The CAL routine was unnecessary, and probably slower
than letting the compiler generate inline code.

W.
.

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