yosys/tests/various/peepopt.ys

read_verilog <<EOT
module peepopt_shiftmul_0 #(parameter N=3, parameter W=3) (input [N*W-1:0] i, input [$clog2(N)-1:0] s, output [W-1:0] o);
assign o = i[s*W+:W];
endmodule
EOT

prep -nokeepdc
equiv_opt -assert peepopt
design -load postopt
clean
select -assert-count 1 t:$shiftx
select -assert-count 0 t:$shiftx t:* %D

####################

design -reset
read_verilog <<EOT
module peepopt_shiftmul_1 (output [7:0] y, input [2:0] w);
assign y = 1'b1 >> (w * (3'b110));
endmodule
EOT

prep -nokeepdc
equiv_opt -assert peepopt
design -load postopt
clean
select -assert-count 1 t:$shr
select -assert-count 1 t:$mul
select -assert-count 0 t:$shr t:$mul %% t:* %D

####################

design -reset
read_verilog <<EOT
module peepopt_shiftmul_2 (input [11:0] D, input [1:0] S, output [11:0] Y);
	assign Y = D >> (S*3);
endmodule
EOT

prep
design -save gold
peepopt
design -stash gate

design -import gold -as gold peepopt_shiftmul_2
design -import gate -as gate peepopt_shiftmul_2

miter -equiv -make_assert -make_outputs -ignore_gold_x -flatten gold gate miter
sat -show-public -enable_undef -prove-asserts miter
cd gate
select -assert-count 1 t:$shr
select -assert-count 1 t:$mul
select -assert-count 0 t:$shr t:$mul %% t:* %D

####################

design -reset
read_verilog <<EOT
module peepopt_muldiv_0(input [1:0] i, output [1:0] o);
wire [3:0] t;
assign t = i * 3;
assign o = t / 3;
endmodule
EOT

prep -nokeepdc
equiv_opt -assert peepopt
design -load postopt
clean
select -assert-count 0 t:*