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8bitworkshop/test/cli/verilog/t_math_signed4.v

142 lines
4.3 KiB
Verilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain, for
// any use, without warranty, 2014 by Wilson Snyder.
// SPDX-License-Identifier: CC0-1.0
`define checkh(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d: got='h%x exp='h%x\n", `__FILE__,`__LINE__, (gotv), (expv)); fail='1; end while(0)
`define checkf(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d: got=%f exp=%f\n", `__FILE__,`__LINE__, (gotv), (expv)); fail='1; end while(0)
module t (/*AUTOARG*/);
bit fail;
localparam signed [3:0] bug737_p1 = 4'b1000;
wire [3:0] bug737_a = 4'b1010;
reg [5:0] bug737_y;
reg signed [3:0] w4_s;
reg signed [4:0] w5_s;
reg [3:0] w4_u;
reg [4:0] w5_u;
reg signed [8:0] w9_s;
real r;
initial begin
// verilator lint_off WIDTH
bug737_y = bug737_a + (bug737_p1 + 4'sb0);
`checkh(bug737_y, 6'b010010); //bug737
// 6u +[6u] 4s +[6s] 6s
bug737_y = 6'b001010 + (4'sb1000 + 6'sb0);
`checkh(bug737_y, 6'b010010); //bug737, getx 000010
// 6u +[6u] 4s +[6s] 6s
bug737_y = 6'b001010 + (4'b1000 + 6'sb0);
`checkh(bug737_y, 6'b010010); //ok
bug737_y = 6'b001010 + (6'sb111000 + 6'sb0);
`checkh(bug737_y, 6'b000010); //ok
// v--- sign extends to 6-bits
bug737_y = 6'sb001010 + (4'sb1000 + 6'sb0);
`checkh(bug737_y, 6'b000010); //ok
// From t_math_signed_3
w4_s = 4'sb1111 - 1'b1;
`checkh(w4_s,33'he);
w4_s = 4'sb1111 - 5'b00001;
`checkh(w4_s,33'he);
w4_s = 4'sb1111 - 1'sb1;
`checkh(w4_s,4'h0);
w5_s = 4'sb1111 - 1'sb1;
`checkh(w5_s,4'h0);
w4_s = 4'sb1111 - 4'sb1111;
`checkh(w4_s,4'h0);
w5_s = 4'sb1111 - 4'sb1111;
`checkh(w5_s,5'h0);
// The assign LHS being signed or unsigned does not matter per IEEE
// The upper add being signed DOES matter propagating to lower
w4_s = 4'sb1111 - (1'sb1 + 4'b0); //1'sb1 not extended as unsigned add
`checkh(w4_s,4'he);
w4_s = 4'sb1111 - (1'sb1 + 4'sb0); //1'sb1 does sign extend
`checkh(w4_s,4'h0);
w4_s = 4'b1111 - (1'sb1 + 4'sb0); //1'sb1 does *NOT* sign extend
`checkh(w4_s,4'he); // BUG, Verilator says 'h0
w5_u = 4'b1111 + 4'b0001; // Extends to 5 bits due to LHS
`checkh(w5_u, 5'b10000);
w4_u = 4'b1111 + 4'b0001; // Normal case
`checkh(w4_u, 4'b0000);
// Another example of promotion, the add is 4 bits wide
w4_u = 3'b111 + 3'b010;
`checkh(w4_u, 4'b1001);
//
w4_u = 3'sb111 * 3'sb001; // Signed output, LHS does not matter
`checkh(w4_u, 4'sb1111);
w4_s = 3'sb111 * 3'sb001; // Signed output
`checkh(w4_s, 4'sb1111);
w4_s = 3'b111 * 3'sb001; // Unsigned output
`checkh(w4_s, 4'b0111);
// Conditionals get width from parent; are assignment-like
w4_u = 1'b0 ? 4'b0 : (2'b01+2'b11);
`checkh(w4_u, 4'b0100);
w4_u = 1'b0 ? 4'b0 : (6'b001000+6'b001000);
`checkh(w4_u, 4'b0000);
// If RHS is larger, that larger size is used
w4_u = 5'b10000 / 5'b00100;
`checkh(w4_u, 4'b0100);
// bug754
w5_u = 4'sb0010 << -2'sd1; // << 3
`ifdef VCS
`checkh(w5_u, 5'b00000); // VCS E-2014.03 bug
`else
`checkh(w5_u, 5'b10000); // VCS E-2014.03 bug
`endif
w5_u = 4'sb1000 << 0; // Sign extends
`checkh(w5_u, 5'b11000);
// Reals do not propagate to children
r = 1.0 + ( 1 + (1 / 2));
`checkf(r, 2.0);
// Self determined sign extension
r = $itor(3'sb111);
`checkf(r, -1.0);
// If any part of case is real, all is real
case (22)
22.0: ;
22.1: $stop;
default: $stop;
endcase
// bug759
w5_u = { -4'sd7 };
`checkh(w5_u, 5'b01001);
w5_u = {2{ -2'sd1 }};
`checkh(w5_u, 5'b01111);
// Don't break concats....
w5_u = {{0{1'b1}}, -4'sd7 };
`checkh(w5_u, 5'b01001);
w9_s = { -4'sd7, -4'sd7 };
`checkh(w9_s, 9'b010011001);
{w5_u, {w4_u}} = 9'b10101_1100;
`checkh(w5_u, 5'b10101);
`checkh(w4_u, 4'b1100);
{w4_u} = 4'b1011;
`checkh(w4_u, 4'b1011);
if (fail) $stop;
$write("*-* All Finished *-*\n");
$finish;
end
endmodule