verilator/test_regress/t/t_lint_latch_3.v

52 lines
1.5 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module for Issue#1609
//
// This file ONLY is placed into the Public Domain, for any use,
// without warranty, 2020 by Julien Margetts.
// SPDX-License-Identifier: Unlicense
module t (/*AUTOARG*/ out, out2, in );
input [9:0] in;
output reg [3:0] out;
output reg [3:0] out2;
// Should be no latch here since the input space is fully covered
always @* begin
casez (in)
10'b0000000000 : out = 4'h0;
10'b?????????1 : out = 4'h0;
10'b????????10 : out = 4'h1;
10'b???????100 : out = 4'h2;
10'b??????1000 : out = 4'h3;
10'b?????10000 : out = 4'h4;
10'b????100000 : out = 4'h5;
10'b???1000000 : out = 4'h6;
10'b??10000000 : out = 4'h7;
10'b?100000000 : out = 4'h8;
10'b1000000000 : out = 4'h9;
endcase
end
// Should detect a latch here since not all paths assign
// BUT we don't because warnOff(LATCH) is set for any always containing a
// complex case statement
always @* begin
casez (in)
10'b0000000000 : out2 = 4'h0;
10'b?????????1 : out2 = 4'h0;
10'b????????10 : out2 = 4'h1;
10'b???????100 : out2 = 4'h2;
10'b??????1000 : out2 = 4'h3;
10'b?????10000 : /* No assignement */ ;
10'b????100000 : out2 = 4'h5;
10'b???1000000 : out2 = 4'h6;
10'b??10000000 : out2 = 4'h7;
10'b?100000000 : out2 = 4'h8;
10'b1000000000 : out2 = 4'h9;
endcase
end
endmodule