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From: "xry111 at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/111252] LoongArch: Suboptimal code for (a & ~mask) | (b
 & mask) where mask is a constant with value ((1 << n) - 1) << m
Date: Thu, 31 Aug 2023 04:54:41 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111252

--- Comment #5 from Xi Ruoyao <xry111 at gcc dot gnu.org> ---
(In reply to Xi Ruoyao from comment #4)

> Hmm, this seems a separate issue.  The compiler knows to optimize (a & ma=
sk)
> if mask is ((1 << a) - 1) << b iff a + b =3D 32 or b =3D 0, but not for a=
ny

I mean "32 or 64".

> other masks even if it's "expensive" to materialize the mask:=