added population count in generic modules

pipelined/src/generic/popcnt.sv

@@ -0,0 +1,40 @@
+
+///////////////////////////////////////////
+//
+// Written: Kevin Kim <kekim@hmc.edu>
+// Modified: 2/4/2023
+//
+// Purpose: Population Count
+// 
+// A component of the CORE-V-WALLY configurable RISC-V project.
+// 
+// Copyright (C) 2021-23 Harvey Mudd College & Oklahoma State University
+//
+// SPDX-License-Identifier: Apache-2.0 WITH SHL-2.1
+//
+// Licensed under the Solderpad Hardware License v 2.1 (the “License”); you may not use this file 
+// except in compliance with the License, or, at your option, the Apache License version 2.0. You 
+// may obtain a copy of the License at
+//
+// https://solderpad.org/licenses/SHL-2.1/
+//
+// Unless required by applicable law or agreed to in writing, any work distributed under the 
+// License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, 
+// either express or implied. See the License for the specific language governing permissions 
+// and limitations under the License.
+////////////////////////////////////////////////////////////////////////////////////////////////
+
+module popcnt #(parameter WIDTH = 32) (
+  input logic  [WIDTH-1:0]            num,    // number to count total ones
+  output logic [$clog2(WIDTH):0]  PopCnt  // the total number of ones
+);
+
+  logic [$clog2(WIDTH):0] sum; 
+  genvar i;
+  for (i=0;i<WIDTH;i++) begin:loop
+    assign sum = sum + num[i];
+  end
+  assign PopCnt = sum;
+
+  
+endmodule