https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68097

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2015-10-26
                 CC|                            |rguenth at gcc dot gnu.org
            Version|unknown                     |6.0
     Ever confirmed|0                           |1

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.

Note the main part will be to make the FP "range info" available on SSA names.

Other useful queries would include "cannot be Inf/NaN/signed zero".

Note that transforms based on this (and also nonnegative!) need to be careful
as there are no data dependences on conditions.  Thus with

  if (x > 0.)
   foo (x);

we may not optimize foo based on 'nonnegative' as code motion has no barrier
that prevents it from hoisting it before the if.

Yes, vectors could also be handled (and yes, please one "value range" per
SSA name only).  Likewise complex (integer) types.

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