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Re: Packing booleans?
- From: Nix <nix at esperi dot org dot uk>
- To: "Sam Lauber" <sam124 at operamail dot com>
- Cc: gcc at gcc dot gnu dot org
- Date: Wed, 04 May 2005 13:19:54 +0100
- Subject: Re: Packing booleans?
- References: <20050504062627.3691C416118@ws5-2.us4.outblaze.com>
On 4 May 2005, Sam Lauber stipulated:
> Would it be possible to have a -fpack-bools option that packs booleans into
> the smallest form possible (8 booleans -> 1 8-bit reg, etc.) into a register
> (or memory, as the case may be)?
How could you do that without breaking the semantics of the program?
Among other things, you couldn't take the address of such a packed
boolean: if the idea is to quietly suppress boolean packing for booleans
whose address is taken, then this will suppress packing for any boolean
shared between translation units, or possibly even between procedures.
--
`End users are just test loads for verifying that the system works, kind of
like resistors in an electrical circuit.' - Kaz Kylheku in c.o.l.d.s