Re: Fix asm constraint in put_user

Andreas Schwab
2005-11-21T16:48:31Z

David Mosberger-Tang <David.Mosberger@acm.org> writes:

> If memory services, you should use the "o" constraint instead.

That doesn't work.

> Note that there is no "memory" clobber, so if you change from "m" to "r"
> constraint, GCC won't know that the location at "addr" is being stored
> to.

There is nothing worth clobbering here. The memory written to is
completely separate to anything GCC knows about. The old version didn't
clobber either.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@suse.de
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