verilator/test_regress/t/t_const_opt_shortcut.v
2021-11-13 10:46:25 -05:00

94 lines
2.6 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2021 Yutetsu TAKATSUKASA.
// SPDX-License-Identifier: CC0-1.0
import "DPI-C" context function int import_func0();
import "DPI-C" context function int import_func1();
import "DPI-C" context function int import_func2();
import "DPI-C" context function int import_func3();
import "DPI-C" context function int import_func4();
module t(/*AUTOARG*/
// Inputs
clk
);
input clk;
integer cyc = 0;
reg [63:0] crc;
reg [63:0] sum;
// Take CRC data and apply to testblock inputs
wire [31:0] in = crc[31:0];
wire [31:0] i = crc[31:0];
wire out;
Test test(
// Outputs
.out (out),
// Inputs
.clk (clk),
.i (i[31:0]));
wire [63:0] result = {63'b0, out};
// Test loop
always @ (posedge clk) begin
`ifdef TEST_VERBOSE
$write("[%0t] cyc==%0d crc=%x result=%x\n", $time, cyc, crc, result);
`endif
cyc <= cyc + 1;
crc <= {crc[62:0], crc[63] ^ crc[2] ^ crc[0]};
sum <= result ^ {sum[62:0], sum[63] ^ sum[2] ^ sum[0]};
if (cyc == 0) begin
// Setup
crc <= 64'h5aef0c8d_d70a4497;
sum <= '0;
end
else if (cyc < 10) begin
sum <= '0;
end
else if (cyc == 99) begin
$write("[%0t] cyc==%0d crc=%x sum=%x\n", $time, cyc, crc, sum);
if (crc !== 64'hc77bb9b3784ea091) $stop;
if (import_func1() != 1) $stop; // this must be the first call
if (import_func3() != 1) $stop; // this must be the first call
if (import_func4() < 95) $stop; // expected to return around 100
// What checksum will we end up with (above print should match)
`define EXPECTED_SUM 64'h162c58b1635b8d6e
if (sum !== `EXPECTED_SUM) $stop;
$write("*-* All Finished *-*\n");
$finish;
end
end
endmodule
module Test(/*AUTOARG*/
// Outputs
out,
// Inputs
clk, i
);
input clk;
input [31:0] i;
output wire out;
logic [2:0] tmp;
assign out = ^tmp;
always_ff @(posedge clk) begin
// Note that import_func?() always returns positive integer,
// so '|(import_func?())' is always 1'b1
tmp[0] <= |(import_func0()) || |(import_func1()); // import_fnc1 must not be called
tmp[1] <= !(|(import_func2())) && |(import_func3()); // import_fnc3 must not be called
tmp[2] <= ^(0 * import_func4()); // import_func1 has side effect, so must be executed anyway.
end
endmodule