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Re: [PR23664] Fold (a & C1) + (b & C2) to (a & C1) | (b & C2) iff (C1 & C2) == 0
- From: Marc Glisse <marc dot glisse at inria dot fr>
- To: "Hurugalawadi, Naveen" <Naveen dot Hurugalawadi at caviumnetworks dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Tue, 7 Jul 2015 07:56:51 +0200 (CEST)
- Subject: Re: [PR23664] Fold (a & C1) + (b & C2) to (a & C1) | (b & C2) iff (C1 & C2) == 0
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On Tue, 7 Jul 2015, Hurugalawadi, Naveen wrote:
Please find attached the patch "PR23664.patch" that converts the pattern:-
(a & C1) + (b & C2) into (a & C1) | (b & C2) iff (C1 & C2) == 0.
We already have the following. I believe it would be better to merge them
(use a 'for').
(simplify
(bit_xor (convert1? (bit_and@4 @0 INTEGER_CST@1))
(convert2? (bit_and@5 @2 INTEGER_CST@3)))
(if (tree_nop_conversion_p (type, TREE_TYPE (@0))
&& tree_nop_conversion_p (type, TREE_TYPE (@2))
&& wi::bit_and (@1, @3) == 0)
(bit_ior (convert @4) (convert @5))))
--
Marc Glisse