Re: [tip:x86/mm] x86, mm: Use a bitfield to mask nuisance get_user()warnings

[H. Peter Anvin]

Just to be sure, I re-ran the comparison using gcc 4.6.3 instead of gcc
4.7.2.  With gcc 4.6.3 I consistently get a few hundred bytes longer
with the bitfield variant than with the pre-get_user() baseline.

I looked at some of the diffed disassembly, and the differences seem to
be in the code generated downstream of __get_user_1 and __get_user_2,
which I guess is to be expected, mostly in the form of padding.

Annoyingly enough in *both* cases I found unnecessary instructions like:

+c12f6fbb:      0f b7 d2                movzwl %dx,%edx

	-hpa

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