Help with cross-endian bitfields?

[Josh Huber]

On Fri, May 05, 2000 at 04:05:52PM -0400, Dan Malek wrote:
> IMHO, bit fields are not normally a good thing to be using if this is
> describing a real device register.  The compiler is able to read/write
> in ways that may not be proper for hardware access.  For device registers
> and when this is a data structure in memory, the cross-platform method
> of using macros for reading writing 16- and 32-bit values and then 'C'
> operators for testing/setting bits has worked pretty well in the past.....
Yeah, I just looked in the PowerPC ABI for bitfield storage, and the
relevant text said:
* Bit-fields are allocated from right to left (least to most significant) on
Little-Endian implementations and from left to right (most to least
significant) on Big-Endian implementations.

Josh

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