verilator/test_regress/t/t_opt_constpool_recache.v

76 lines
2.1 KiB
Systemverilog

// DESCRIPTION: Verilator: Verilog Test module
//
// This file ONLY is placed under the Creative Commons Public Domain.
// SPDX-FileCopyrightText: 2026 Wilson Snyder
// SPDX-License-Identifier: CC0-1.0
// verilog_format: off
`define stop $stop
`define checkh(gotv,expv) do if ((gotv) !== (expv)) begin $write("%%Error: %s:%0d: got=%0x exp=%0x (%s !== %s)\n", `__FILE__,`__LINE__, (gotv), (expv), `"gotv`", `"expv`"); `stop; end while(0);
// verilog_format: on
module t;
logic clk = 1'b0;
always #5 clk = ~clk;
logic [31:0] cyc = 0;
logic [3:0] idx;
assign idx = cyc[3:0];
// V3Case lowers this to a 512-bit constant-pool lookup table before V3Dead
// calls AstConstPool::rebuildVarScopesAndCache().
logic [31:0] case_word;
always_comb
case (idx)
4'h0: case_word = 32'h00000000;
4'h1: case_word = 32'h00000001;
4'h2: case_word = 32'h00000002;
4'h3: case_word = 32'h00000003;
4'h4: case_word = 32'h00000004;
4'h5: case_word = 32'h00000005;
4'h6: case_word = 32'h00000006;
4'h7: case_word = 32'h00000007;
4'h8: case_word = 32'h00000008;
4'h9: case_word = 32'h00000009;
4'ha: case_word = 32'h0000000a;
4'hb: case_word = 32'h0000000b;
4'hc: case_word = 32'h0000000c;
4'hd: case_word = 32'h0000000d;
4'he: case_word = 32'h0000000e;
default: case_word = 32'h0000000f;
endcase
localparam logic [511:0] TABLE = {
32'h0000000f,
32'h0000000e,
32'h0000000d,
32'h0000000c,
32'h0000000b,
32'h0000000a,
32'h00000009,
32'h00000008,
32'h00000007,
32'h00000006,
32'h00000005,
32'h00000004,
32'h00000003,
32'h00000002,
32'h00000001,
32'h00000000
};
// V3Premit extracts this matching wide constant after V3Dead recached the
// const-pool contents created by V3Case.
logic [31:0] static_word;
assign static_word = TABLE[{idx, 5'b0} +: 32];
always @(posedge clk) begin
`checkh(case_word, static_word);
cyc <= cyc + 32'd1;
if (cyc == 32'd32) begin
$write("*-* All Finished *-*\n");
$finish;
end
end
endmodule