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// ========== Copyright Header Begin ==========================================
//
// OpenSPARC T1 Processor File: sparc_exu_alulogic.v
// Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
// DO NOT ALTER OR REMOVE COPYRIGHT NOTICES.
//
// The above named program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public
// License version 2 as published by the Free Software Foundation.
//
// The above named 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 work; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
//
// ========== Copyright Header End ============================================
////////////////////////////////////////////////////////////////////////
/*
//
// Module Name: sparc_exu_alulogic
// Description: This block implements and, or, xor, xnor, nand, nor
// and pass_rs2_data. And, or, Xor and pass are muxed together
// and then xored with an inversion signal to create
// xnor, nand and nor. Both inputs are buffered before being
// used and the rs2_data signal is buffered again before going
// to the mux.
*/
module sparc_exu_alulogic (/*AUTOARG*/
// Outputs
logic_out,
// Inputs
rs1_data, rs2_data, isand, isor, isxor, pass_rs2_data, inv_logic,
ifu_exu_sethi_inst_e
);
input [63:0] rs1_data; // 1st input operand
input [63:0] rs2_data; // 2nd input operand
input isand;
input isor;
input isxor;
input pass_rs2_data;
input inv_logic;
input ifu_exu_sethi_inst_e; // zero out top half of rs2 on mov
output [63:0] logic_out; // output of logic block
wire [63:0] rs1_data_bf1; // buffered rs1_data
wire [63:0] rs2_data_bf1; // buffered rs2_data
wire [63:0] mov_data;
wire [63:0] result_and; // rs1_data & rs2_data
wire [63:0] result_or; // rs1_data | rs2_data
wire [63:0] result_xor; // rs1_data ^ rs2_data
wire [63:0] rs2_xor_invert; // output of mux between various results
// mux between various results
mux4ds #(64) logic_mux(.dout(logic_out[63:0]),
.in0(result_and[63:0]),
.in1(result_or[63:0]),
.in2(result_xor[63:0]),
.in3(mov_data[63:0]),
.sel0(isand),
.sel1(isor),
.sel2(isxor),
.sel3(pass_rs2_data));
// buffer inputs
dp_buffer #(64) rs1_data_buf(.dout(rs1_data_bf1[63:0]), .in(rs1_data[63:0]));
dp_buffer #(64) rs2_data_buf(.dout(rs2_data_bf1[63:0]), .in(rs2_data[63:0]));
// zero out top of rs2 for sethi_inst
assign mov_data[63:32] = rs2_data_bf1[63:32] & {32{~ifu_exu_sethi_inst_e}};
dp_buffer #(32) rs2_data_buf2(.dout(mov_data[31:0]), .in(rs2_data_bf1[31:0]));
// invert input2 for andn, orn, xnor
assign rs2_xor_invert[63:0] = rs2_data_bf1[63:0] ^ {64{inv_logic}};
// do boolean ops
assign result_and = rs1_data_bf1 & rs2_xor_invert;
assign result_or = rs1_data_bf1 | rs2_xor_invert;
assign result_xor = rs1_data_bf1 ^ rs2_xor_invert;
endmodule