refactor intrinsic_op

[thewilsonator]

rebase of #8002

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[thewilsonator]

WTF is with circle? The code explicitly checks to disable 64bit bswap.

[thewilsonator]

std.math:3789 fails assert(ilogb(nextUp(-double.min_normal)) == -1023);
std.bitmanip fails in

static foreach (T; AliasSeq!(byte, short, int, long))
    assert(bitsSet(T.min).equal([8 * T.sizeof - 1]));

[thewilsonator]

Hmm, ilogb uses bsr, bitsSet uses bsf, maybe fd.parameters && (*fd.parameters)[0].type == Type.tuns64 doesn't work the way I think it should?

[thewilsonator]

Aaaaand back to the fail on 32bit.

[thewilsonator]

deleting this so the druntime PR on branch with same name works, will come back to this soon.

[rainers]

deleting this so the druntime PR on branch with same name works, will come back to this soon.

IIRC this only happens if the branch is from the dlang repository, not your fork. Unfortunately, when starting a patch from the web interface it defaults to use dlang.

[thewilsonator]

And its mode more complicated by the fact that my druntime fork is from LDC.

[PetarKirov]

@thewilsonator if you click on the "Fork" button on the upstream repo, you get to choose where you want to make a new fork: to your personal account, or to any organization you have the rights to do so.