Thanks for the useful benchmarking info vs Perl's vec(), and my apologies for lack of clarity in the OP. In answer to your queries:

>>If the real code is so complex, why are you asking us to make judgements based on such a trivial example that can never meet its stated goal of greater efficiency?<< I was trying to present a 'minimal case' to illustrate the particular aspects I'm unsure about.

>>The way you've asked the question suggests that you are unsure about the parameter handling rather than the actual internal logic. Where exactly do your doubts lie?<< What I'm unsure about is two things:

(a) Correct method for directly accessing the bytes of a Perl variable from Inline C? My example works but I'm not entirely sure it's the "right way". Is casting the return of SvPV to an unsigned char* a sensible thing to be doing?

(b) Whether directly changing the bytes of a Perl variable in C runs the risk of 'breaking' Perl internals in some scenarios?

In reply to Re^2: Bit vector fiddling with Inline C by oxone
in thread Bit vector fiddling with Inline C by oxone

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