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// test case generated from IWLS 2005 usb_phy core
// (triggered a bug in opt_muxtree pass)
module usb_tx_phy(clk, rst, DataOut_i, TxValid_i, hold_reg);
input clk;
input rst;
input DataOut_i;
input TxValid_i;
output reg hold_reg;
reg state, next_state;
reg ld_sop_d;
reg ld_data_d;
always @(posedge clk)
if(ld_sop_d)
hold_reg <= 0;
else
hold_reg <= DataOut_i;
always @(posedge clk)
if(!rst) state <= 0;
else state <= next_state;
always @(state or TxValid_i)
begin
next_state = state;
ld_sop_d = 1'b0;
ld_data_d = 1'b0;
case(state) // synopsys full_case parallel_case
0:
if(TxValid_i)
begin
ld_sop_d = 1'b1;
next_state = 1;
end
1:
if(TxValid_i)
begin
ld_data_d = 1'b1;
next_state = 0;
end
endcase
end
endmodule
// test case inspired by softusb_navre code:
// default not as last case
module default_cases(a, y);
input [2:0] a;
output reg [3:0] y;
always @* begin
case (a)
3'b000, 3'b111: y <= 0;
default: y <= 4;
3'b001: y <= 1;
3'b010: y <= 2;
3'b100: y <= 3;
endcase
end
endmodule
// test case for muxtree with select on leaves
module select_leaves(input R, C, D, output reg Q);
always @(posedge C)
if (!R)
Q <= R;
else
Q <= Q ? Q : D ? D : Q;
endmodule
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