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// DESCRIPTION: Verilator: Dedupe optimization test.
//
// This file ONLY is placed into the Public Domain, for any use,
// without warranty.
// SPDX-License-Identifier: CC0-1.0
// Contributed 2012 by Varun Koyyalagunta, Centaur Technology.
//
// Test consists of the follow logic tree, which has many obvious
// places for dedupe:
/*
output
+
--------------/ \--------------
/ \
+ +
----/ \----- ----/ \----
/ + / +
+ / \ + / \
-/ \- a b -/ \- a b
/ \ / \
+ + + +
/ \ / \ / \ / \
a b c d a b c d
*/
module t(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
wire left,right;
add add(sum,left,right,clk);
l l(left,a,b,c,d,clk);
r r(right,a,b,c,d,clk);
endmodule
module l(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
wire left, right;
add add(sum,left,right,clk);
ll ll(left,a,b,c,d,clk);
lr lr(right,a,b,c,d,clk);
endmodule
module ll(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
wire left, right;
add add(sum,left,right,clk);
lll lll(left,a,b,c,d,clk);
llr llr(right,a,b,c,d,clk);
endmodule
module lll(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
add add(sum,a,b,clk);
endmodule
module llr(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
add add(sum,c,d,clk);
endmodule
module lr(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
add add(sum,a,b,clk);
endmodule
module r(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
wire left, right;
add add(sum,left,right,clk);
rl rl(left,a,b,c,d,clk);
rr rr(right,a,b,c,d,clk);
endmodule
module rr(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
add add(sum,a,b,clk);
endmodule
module rl(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
wire left, right;
add add(sum,left,right,clk);
rll rll(left,a,b,c,d,clk);
rlr rlr(right,a,b,c,d,clk);
endmodule
module rll(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
add2 add(sum,a,b,clk);
endmodule
module rlr(sum,a,b,c,d,clk);
output sum;
input a,b,c,d,clk;
add2 add(sum,c,d,clk);
endmodule
module add(sum,x,y,clk);
output reg sum;
input x,y,clk;
reg t1,t2;
always @(posedge clk) begin
sum <= x + y;
end
endmodule
module add2(sum,x,y,clk);
output reg sum;
input x,y,clk;
reg t1,t2;
always @(posedge clk) begin
sum <= x + y;
end
endmodule
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