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Re: actually sign-extending CONST_INTs in expand_binop


On Apr 24, 2001, Joern Rennecke <amylaar@cambridge.redhat.com> wrote:

> ! 	 When we have an extending integer operation, e.g. umulhisi,
> ! 	 we have to pass MODE (which is wider) as the previous mode.

Why?  Aren't the operands supposed to be valid HImode values already?

> ! 	 However, we must not do this if MODE is not a MODE_INT mode,
> ! 	 since then the operation becomes nonsentical - fall back to the
> ! 	 MODE0 / MODE1 no-op then.  */
  
Is there any case in which we get to that point with mode0 != mode
such that they aren't integer modes?

-- 
Alexandre Oliva   Enjoy Guarana', see http://www.ic.unicamp.br/~oliva/
Red Hat GCC Developer                  aoliva@{cygnus.com, redhat.com}
CS PhD student at IC-Unicamp        oliva@{lsd.ic.unicamp.br, gnu.org}
Free Software Evangelist    *Please* write to mailing lists, not to me


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