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From: "ebotcazou at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug rtl-optimization/104405] Inefficient register allocation on
 complex arithmetic
Date: Mon, 07 Feb 2022 09:02:56 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D104405

--- Comment #8 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> There is of course the option to switch to alternate heuristics if, by
> heuristic, the argument/return part of the function is a big part of it (=
aka
> for toy examples or small functions which do happen in real-life).

Indeed a solution to be considered, but then...

> Also toy examples can highlight issues that also exist in the real world.

...you break the connection between toy examples and real world even more.

In any case, I'm not a RA specialist so I'll stop there, but my understandi=
ng
is that you don't build a good RA for real world code by examining a list of
reduced cases and trying to make it optimal for each of them.=