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+// -*- verilog -*-
+//
+// USRP - Universal Software Radio Peripheral
+//
+// Copyright (C) 2008 Matt Ettus
+//
+// 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, Boston, MA 02110-1301 USA
+//
+
+// Clipping "macro", keeps the bottom bits
+
+module clip
+ #(parameter bits_in=0,
+ parameter bits_out=0)
+ (input [bits_in-1:0] in,
+ output [bits_out-1:0] out);
+
+ wire overflow = |in[bits_in-1:bits_out-1] & ~(&in[bits_in-1:bits_out-1]);
+ assign out = overflow ?
+ (in[bits_in-1] ? {1'b1,{(bits_out-1){1'b0}}} : {1'b0,{(bits_out-1){1'b1}}}) :
+ in[bits_out-1:0];
+
+endmodule // clip
+