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Re: SUBREGs and modes
> > weird usage of SUBREGs. According to my uderstanding the docs, when
> > WORDNUM is nonzero, the innermode must be greater than word and
> > the outer mode must be word.
>
> Where does it say that the outer mode must be word?
The other use of @code{subreg} is to extract the individual registers of
a multi-register value. Machine modes such as @code{DImode} and
@code{TImode} can indicate values longer than a word, values which
usually require two or more consecutive registers. To access one of the
registers, use a @code{subreg} with mode @code{SImode} and a
@var{wordnum} that says which register.
Actually speaks about SImode, but is interpreted in the code as
word.
Honza