Re: __LITTLE_ENDIAN vs. __LITTLE_ENDIAN_BITFIELD

From: Andreas Schwab
Date: Fri Oct 05 2007 - 17:17:34 EST


Timur Tabi <timur@xxxxxxxxxxxxx> writes:

> Then I don't understand that point of defining __LITTLE_ENDIAN_BITFIELD.
> What does it mean for a C-level bitfield ordering to be little-endian if
> the processor is BIG_ENDIAN?

Byte endianess and bit endianness are orthogonal concecpts. A cpu can
have insns using both little and big endian bit addressing (btst
vs. bftst on m68k). The bitfield ordering is a property of the ABI and
may even be different from how the cpu numbers the bits in its ISA.

Andreas.

--
Andreas Schwab, SuSE Labs, schwab@xxxxxxx
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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