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-- Build utilities
-- Copyright (C) 2019 Tristan Gingold
--
-- This file is part of GHDL.
--
-- This program is free software; you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation; either version 2 of the License, or
-- (at your option) any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-- GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program; if not, write to the Free Software
-- Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
-- MA 02110-1301, USA.
with Ada.Unchecked_Deallocation;
with Netlists.Builders; use Netlists.Builders;
with Synth.Source; use Synth.Source;
package Netlists.Butils is
type Case_Element is record
Sel : Uns64;
Val : Net;
end record;
type Case_Element_Array is array (Natural range <>) of Case_Element;
type Case_Element_Array_Acc is access Case_Element_Array;
procedure Free_Case_Element_Array is new Ada.Unchecked_Deallocation
(Case_Element_Array, Case_Element_Array_Acc);
-- Generate a netlist for a 'big' mux selected by SEL. The inputs are
-- described by ELS: E.Val must be selected when SEL = E.Sel; if there
-- is no E in Els for a value, DEFAULT is selected.
-- The result of the netlist is stored in RES.
--
-- A tree of MUX4 is built.
--
-- ELS must be sorted by SEL values.
-- ELS is overwritten/modified so after the call it contains garbage. The
-- reason is that ELS might be large, so temporary arrays are not allocated
-- on the stack, and ELS is expected to be built only for this subprogram.
procedure Synth_Case (Ctxt : Context_Acc;
Sel : Net;
Els : in out Case_Element_Array;
Default : Net;
Res : out Net;
Sel_Loc : Syn_Src);
end Netlists.Butils;
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