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// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2003-2008 by Wilson Snyder.
// SPDX-License-Identifier: CC0-1.0
module t (clk);
input clk;
integer cyc; initial cyc=1;
integer sum;
integer cpre;
always @ (posedge clk) begin
if (cyc!=0) begin
cpre = cyc;
cyc <= cyc + 1;
if (cyc==1) begin
if (mlog2(32'd0) != 32'd0) $stop;
if (mlog2(32'd1) != 32'd0) $stop;
if (mlog2(32'd3) != 32'd2) $stop;
sum <= 32'd0;
end
else if (cyc<90) begin
// (cyc) so if we trash the variable things will get upset.
sum <= mlog2(cyc) + sum * 32'd42;
if (cpre != cyc) $stop;
end
else if (cyc==90) begin
if (sum !== 32'h0f12bb51) $stop;
$write("*-* All Finished *-*\n");
$finish;
end
end
end
function integer mlog2;
input [31:0] value;
integer i;
begin
if(value < 32'd1) begin
mlog2 = 0;
end
else begin
value = value - 32'd1;
mlog2 = 0;
for(i=0;i<32;i=i+1) begin
if(value > 32'd0) begin
mlog2 = mlog2 + 1;
end
value = value >> 1;
end
end
end
endfunction
endmodule
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