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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/114270] Integer multiplication on floating point
 constant with conversion back to integer is not optimized
Date: Thu, 07 Mar 2024 15:50:34 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114270

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |enhancement

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The rules for this to be done are a bit more complex than what is described
here.

1) Significand precision of the floating point type needs to be >=3D precis=
ion of
the integer type
2) the 1/(multiplier) needs to be representable in the integer type
3) (I think this is required) no trapping math is enabled as inexact floati=
ng
point exception could happen
4) (maybe?) Significand only has the implicit 1 set.

Note there might be more rules on needed for this to be done and I have not
thought about all of them currently.=