But you had previously stated that _BitInt(384) doesn't satisfy the alignment requirements to do that.
Which is it? Does it align to 8bytes or 64bytes?
And those that says that somehow on some compilers that's what it does, despite the fact that the alignment is _BitInt is not defined, it means that it may work anyhow in practice but only because the compiler took an optimization path that was never guaranteed to be there in the first place.

-----Original Message-----
From: Jan Schultke <janschultke_at_googlemail.com>
Sent: Thursday, September 4, 2025 08:53
To: Tiago Freire <tmiguelf_at_[hidden]>
Cc: std-proposals_at_lists.isocpp.org
Subject: Re: [std-proposals] D3666R0 Bit-precise integers

> A CPU may not be able to perform unaligned loads and stores.

Sure. That's why _BitInt(384) should have sufficient alignment requirements so it can be loaded into such a SHA acceleration register in a single load operation of some kind.

I'm still not seeing where the "Vodoo" is. This is basic and commonly understood stuff.