[Bug middle-end/66588] combine should try transforming if_then_else of zero_extends into zero_extend of if_then_else

["ktkachov at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66588

--- Comment #3 from ktkachov at gcc dot gnu.org ---
(In reply to Uroš Bizjak from comment #2)
> (In reply to Uroš Bizjak from comment #1)
> > BTW: x86_64 is missing any form of zero-extended cmove.
> 
> ... please see [1] how x86_64 implements it (*movsicc_noc_zext).
> 
> [1] https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01306.html

Thanks. As I mentioned in the original post this approach does work.
I was just hoping to argue that combine should automatically try both the
(zero_extend (if_then_else a b c))
and
(if_then_else a (zero_extend b) (zero_extend c))

In fact, wouldn't transforming:
(if_then_else a (zero_extend b) (zero_extend c))
into
(zero_extend (if_then_else a b c))
be considered a simplification
suitable for simplify-rtx.c ?
>From gcc-bugs-return-489379-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Fri Jun 19 08:36:27 2015
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From: "mikael at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug fortran/66578] [F2008] Invalid free on allocate(...,source=a(:)) in block
Date: Fri, 19 Jun 2015 08:36:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idf578

--- Comment #10 from Mikael Morin <mikael at gcc dot gnu.org> ---
(In reply to Thomas Koenig from comment #9)
> Unfortunately, this does not appear to fix the bug (at least not completely).
> I still get an invalid free.

Indeed, unfortunately this:

(In reply to Mikael Morin from comment #7)
> Don't care about the scalarizer; generate a correct descriptor to begin
> with, and the scalarizer will follow (hopefully).

is not true.