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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug tree-optimization/103855] Missed optimization: 64bit division
 used instead of 32bit division
Date: Wed, 29 Dec 2021 09:41:12 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103855

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
vect_get_range_info is meant for the vectorizer only, what you want is I th=
ink
get_min_precision which would need to be exported out of internal-fn.c.
In any case, it needs to be called still on the trees (SSA_NAMEs or
INTEGER_CSTs etc.) during expansion.
expand_expr_divmod already performs a different optimization - if both oper=
ands
are known to have the most significant bit clear (checked with
get_range_pos_neg), then it expands it as both signed and unsigned division=
 or
modulo and checks if one of them isn't cheaper.=