Messages in this thread | | | Date | Wed, 09 Dec 2009 21:03:43 +0100 | From | Jiri Slaby <> | Subject | Re: [PATCH 1/1] X86: use explicit register name for get/put_user |
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On 12/07/2009 07:35 PM, H. Peter Anvin wrote: > On 12/07/2009 04:37 AM, Jiri Slaby wrote: >> In the document they write only about the "same location" occupied by in >> and out, nothing is said about size (and hence I think we cannot >> mismatch size of operands). And I couldn't find any other >> restrictions/documentation about inline assembly, hence the patch, >> because nothing assured me this cannot change in the future. > > There is almost no documentation at all; some of the little > documentation there is is in comments in the source code. To a first > order of approximation, asm() is defined by behavior, not by a written > spec. Trying to play language lawyer with the little bit that is > written down is pointless -- the gcc people have been more than happy to > break asm() between releases regardless of what is and is not written down.
Ok, thanks for the explanation.
-- js
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