yosys/tests/csa_tree/csa_tree_negative.ys

read_verilog <<EOT
module add2(
	input [7:0] a, b,
	output [7:0] y
);
	assign y = a + b;
endmodule
EOT
hierarchy -auto-top
proc
csa_tree
select -assert-none t:$fa
select -assert-count 1 t:$add
design -reset

read_verilog <<EOT
module add_fanout(
	input [7:0] a, b, c,
	output [7:0] mid, y
);
	wire [7:0] ab = a + b;
	assign mid = ab;
	assign y = ab + c;
endmodule
EOT
hierarchy -auto-top
proc
csa_tree
select -assert-none t:$fa
design -reset

read_verilog <<EOT
module sub2(
	input [7:0] a, b,
	output [7:0] y
);
	assign y = a - b;
endmodule
EOT
hierarchy -auto-top
proc
csa_tree
select -assert-none t:$fa
select -assert-count 1 t:$sub
design -reset

read_verilog <<EOT
module add_multi_const(
	input [7:0] x,
	output [7:0] y
);
	assign y = 8'd1 + 8'd2 + 8'd3 + x;
endmodule
EOT
hierarchy -auto-top
proc
csa_tree
select -assert-none t:$fa
select -assert-max 1 t:$add
design -reset

read_verilog <<EOT
module add_partial(
	input [7:0] a, b, c, d, e,
	output [7:0] mid, y
);
	wire [7:0] ab = a + b;
	assign mid = ab;
	assign y = ab + c + d + e;
endmodule
EOT
hierarchy -auto-top
proc
csa_tree
select -assert-count 2 t:$fa
select -assert-count 2 t:$add
design -reset