--- /dev/null
+
+read_verilog <<EOT
+module opt_expr_add_test(input [3:0] i, input [7:0] j, output [8:0] o);
+ assign o = (i << 4) + j;
+endmodule
+EOT
+
+hierarchy -auto-top
+proc
+design -save gold
+
+opt_expr -fine
+wreduce
+
+select -assert-count 1 t:$add r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+miter -equiv -flatten -make_assert -make_outputs gold gate miter
+sat -verify -prove-asserts -show-ports miter
+
+##########
+
+read_verilog <<EOT
+module opt_expr_add_signed_test(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
+ assign o = (i << 4) + j;
+endmodule
+EOT
+
+hierarchy -auto-top
+proc
+design -save gold
+
+opt_expr -fine
+wreduce
+
+select -assert-count 1 t:$add r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+miter -equiv -flatten -make_assert -make_outputs gold gate miter
+sat -verify -prove-asserts -show-ports miter
+
+##########
+
+read_verilog <<EOT
+module opt_expr_sub_test1(input [3:0] i, input [7:0] j, output [8:0] o);
+ assign o = j - (i << 4);
+endmodule
+EOT
+
+hierarchy -auto-top
+proc
+design -save gold
+
+opt_expr -fine
+wreduce
+
+select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+miter -equiv -flatten -make_assert -make_outputs gold gate miter
+sat -verify -prove-asserts -show-ports miter
+
+##########
+
+read_verilog <<EOT
+module opt_expr_sub_signed_test1(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
+ assign o = j - (i << 4);
+endmodule
+EOT
+
+hierarchy -auto-top
+proc
+design -save gold
+
+opt_expr -fine
+wreduce
+
+select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+miter -equiv -flatten -make_assert -make_outputs gold gate miter
+sat -verify -prove-asserts -show-ports miter
+
+##########
+
+read_verilog <<EOT
+module opt_expr_sub_test2(input [3:0] i, input [7:0] j, output [8:0] o);
+ assign o = (i << 4) - j;
+endmodule
+EOT
+
+hierarchy -auto-top
+proc
+design -save gold
+
+opt_expr -fine
+wreduce
+
+select -assert-count 1 t:$sub r:A_WIDTH=8 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+miter -equiv -flatten -make_assert -make_outputs gold gate miter
+sat -verify -prove-asserts -show-ports miter
+
+##########
+
+read_verilog <<EOT
+module opt_expr_sub_test4(input [3:0] i, output [8:0] o);
+ assign o = 5'b00010 - i;
+endmodule
+EOT
+
+hierarchy -auto-top
+proc
+design -save gold
+
+opt_expr -fine
+wreduce
+
+select -assert-count 1 t:$sub r:A_WIDTH=2 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+miter -equiv -flatten -make_assert -make_outputs gold gate miter
+sat -verify -prove-asserts -show-ports miter
+++ /dev/null
-module top (
- input clk,
- output reg [7:0] cnt
-);
- initial cnt = 0;
- always @(posedge clk) begin
- if (cnt < 20)
- cnt <= cnt + 1;
- else
- cnt <= 0;
- end
-endmodule
+++ /dev/null
-read_verilog opt_ff_sat.v
-prep -flatten
-opt_rmdff -sat
-synth
-select -assert-count 5 t:$_DFF_P_
--- /dev/null
+module opt_rmdff_test (input C, input D, input E, output [29:0] Q);
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove0 (.CLK(C), .D(D), .EN(1'b0), .Q(Q[0])); // EN is never active
+(* init = "1'b1" *) wire Q1; assign Q[1] = Q1;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove1 (.CLK(C), .D(D), .EN(1'b0), .Q(Q1)); // EN is never active
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove2 (.CLK(C), .D(D), .EN(1'bx), .Q(Q[2])); // EN is don't care
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) keep3 (.CLK(C), .D(D), .EN(1'b1), .Q(Q[3])); // EN is always active
+(* init = "1'b0" *) wire Q4; assign Q[4] = Q4;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(0), .EN_POLARITY(1)) keep4 (.CLK(C), .D(D), .EN(1'b1), .Q(Q4)); // EN is always active
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove5 (.CLK(C), .D(D), .EN(1'b1), .Q(Q[5])); // EN is never active
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove6 (.CLK(C), .D(D), .EN(1'bx), .Q(Q[6])); // EN is don't care
+(* init = "1'b0" *) wire Q7; assign Q[7] = Q7;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(0), .EN_POLARITY(0)) keep7 (.CLK(C), .D(D), .EN(E), .Q(Q7)); // EN is non constant
+
+\$_DFFE_PP_ remove8 (.C(C), .D(D), .E(1'b0), .Q(Q[8])); // EN is never active
+(* init = "1'b1" *) wire Q9; assign Q[9] = Q9;
+\$_DFFE_PP_ remove9 (.C(C), .D(D), .E(1'b0), .Q(Q9)); // EN is never active
+\$_DFFE_PP_ remove10 (.C(C), .D(D), .E(1'bx), .Q(Q[10])); // EN is don't care
+\$_DFFE_PP_ keep11 (.C(C), .D(D), .E(1'b1), .Q(Q[11])); // EN is always active
+(* init = "1'b0" *) wire Q12; assign Q[12] = Q12;
+\$_DFFE_PP_ keep12 (.C(C), .D(D), .E(1'b1), .Q(Q12)); // EN is always active
+
+\$_DFFE_NN_ remove13 (.C(C), .D(D), .E(1'b1), .Q(Q[13])); // EN is never active
+(* init = "1'b1" *) wire Q14; assign Q[14] = Q14;
+\$_DFFE_NN_ remove14 (.C(C), .D(D), .E(1'b1), .Q(Q14)); // EN is never active
+\$_DFFE_NN_ remove15 (.C(C), .D(D), .E(1'bx), .Q(Q[15])); // EN is don't care
+\$_DFFE_NN_ keep16 (.C(C), .D(D), .E(1'b0), .Q(Q[16])); // EN is always active
+(* init = "1'b0" *) wire Q17; assign Q[17] = Q17;
+\$_DFFE_NN_ keep17 (.C(C), .D(D), .E(1'b0), .Q(Q17)); // EN is always active
+
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove18 (.CLK(1'b0), .D(D), .EN(E), .Q(Q[18])); // CLK is constant
+(* init = "1'b1" *) wire Q19; assign Q[19] = Q19;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove19 (.CLK(1'b1), .D(D), .EN(E), .Q(Q19)); // CLK is constant
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove20 (.CLK(C), .D(1'bx), .EN(E), .Q(Q[20])); // D is undriven, Q has no initial value
+(* init = "1'b0" *) wire Q21; assign Q[21] = Q21;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) keep21 (.CLK(C), .D(1'bx), .EN(E), .Q(Q21)); // D is undriven, Q has initial value
+//\$dffe #(.WIDTH(1), .CLK_POLARITY(0), .EN_POLARITY(1)) remove22 (.CLK(C), .D(1'b0), .EN(1'b1), .Q(Q[22])); // D is constant, no initial Q value, EN is always active
+// // (TODO, Q starts with 1'bx and becomes 1'b0)
+(* init = "1'b0" *) wire Q23; assign Q[23] = Q23;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) noenable23 (.CLK(C), .D(1'b0), .EN(1'b1), .Q(Q23)); // D is constant, initial Q value same as D, EN is always active
+(* init = "1'b1" *) wire Q24; assign Q[24] = Q24;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) keep24 (.CLK(C), .D(1'b0), .EN(1'b0), .Q(Q24)); // D is constant, initial Q value NOT same as D, EN is always active
+(* init = "1'b1" *) wire Q25; assign Q[25] = Q25;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove25 (.CLK(C), .D(1'b0), .EN(1'b1), .Q(Q25)); // D is constant, EN is never active
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove26 (.CLK(C), .D(Q[26]), .EN(1'b1), .Q(Q[26])); // D is Q, EN is always active
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove27 (.CLK(C), .D(Q[27]), .EN(1'b1), .Q(Q[27])); // D is Q, EN is never active, but no initial value
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove28 (.CLK(C), .D(Q[28]), .EN(E), .Q(Q[28])); // EN is nonconst, but no initial value
+(* init = "1'b1" *) wire Q29; assign Q[29] = Q29;
+\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) keep29 (.CLK(C), .D(Q[29]), .EN(1'b1), .Q(Q29)); // EN is always active, but with initial value
+
+endmodule
--- /dev/null
+read_verilog -icells opt_rmdff.v
+prep
+design -stash gold
+read_verilog -icells opt_rmdff.v
+proc
+opt_rmdff
+
+select -assert-count 0 c:remove*
+select -assert-min 7 c:keep*
+select -assert-count 0 t:$dffe 7:$_DFFE_* %u c:noenable* %i
+
+design -stash gate
+
+design -import gold -as gold
+design -import gate -as gate
+
+equiv_make gold gate equiv
+hierarchy -top equiv
+equiv_simple -undef
+equiv_status -assert
+
+design -load gold
+stat
+
+design -load gate
+stat
--- /dev/null
+module top (
+ input clk,
+ output reg [7:0] cnt
+);
+ initial cnt = 0;
+ always @(posedge clk) begin
+ if (cnt < 20)
+ cnt <= cnt + 1;
+ else
+ cnt <= 0;
+ end
+endmodule
--- /dev/null
+read_verilog opt_rmdff_sat.v
+prep -flatten
+opt_rmdff -sat
+synth
+select -assert-count 5 t:$_DFF_P_
+++ /dev/null
-
-read_verilog <<EOT
-module opt_expr_add_test(input [3:0] i, input [7:0] j, output [8:0] o);
- assign o = (i << 4) + j;
-endmodule
-EOT
-
-hierarchy -auto-top
-proc
-design -save gold
-
-opt_expr -fine
-wreduce
-
-select -assert-count 1 t:$add r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-miter -equiv -flatten -make_assert -make_outputs gold gate miter
-sat -verify -prove-asserts -show-ports miter
-
-##########
-
-read_verilog <<EOT
-module opt_expr_add_signed_test(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
- assign o = (i << 4) + j;
-endmodule
-EOT
-
-hierarchy -auto-top
-proc
-design -save gold
-
-opt_expr -fine
-wreduce
-
-select -assert-count 1 t:$add r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-miter -equiv -flatten -make_assert -make_outputs gold gate miter
-sat -verify -prove-asserts -show-ports miter
-
-##########
-
-read_verilog <<EOT
-module opt_expr_sub_test1(input [3:0] i, input [7:0] j, output [8:0] o);
- assign o = j - (i << 4);
-endmodule
-EOT
-
-hierarchy -auto-top
-proc
-design -save gold
-
-opt_expr -fine
-wreduce
-
-select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-miter -equiv -flatten -make_assert -make_outputs gold gate miter
-sat -verify -prove-asserts -show-ports miter
-
-##########
-
-read_verilog <<EOT
-module opt_expr_sub_signed_test1(input signed [3:0] i, input signed [7:0] j, output signed [8:0] o);
- assign o = j - (i << 4);
-endmodule
-EOT
-
-hierarchy -auto-top
-proc
-design -save gold
-
-opt_expr -fine
-wreduce
-
-select -assert-count 1 t:$sub r:A_WIDTH=4 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-miter -equiv -flatten -make_assert -make_outputs gold gate miter
-sat -verify -prove-asserts -show-ports miter
-
-##########
-
-read_verilog <<EOT
-module opt_expr_sub_test2(input [3:0] i, input [7:0] j, output [8:0] o);
- assign o = (i << 4) - j;
-endmodule
-EOT
-
-hierarchy -auto-top
-proc
-design -save gold
-
-opt_expr -fine
-wreduce
-
-select -assert-count 1 t:$sub r:A_WIDTH=8 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-miter -equiv -flatten -make_assert -make_outputs gold gate miter
-sat -verify -prove-asserts -show-ports miter
-
-##########
-
-read_verilog <<EOT
-module opt_expr_sub_test4(input [3:0] i, output [8:0] o);
- assign o = 5'b00010 - i;
-endmodule
-EOT
-
-hierarchy -auto-top
-proc
-design -save gold
-
-opt_expr -fine
-wreduce
-
-select -assert-count 1 t:$sub r:A_WIDTH=2 r:B_WIDTH=4 r:Y_WIDTH=5 %i %i %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-miter -equiv -flatten -make_assert -make_outputs gold gate miter
-sat -verify -prove-asserts -show-ports miter
+++ /dev/null
-module opt_rmdff_test (input C, input D, input E, output [29:0] Q);
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove0 (.CLK(C), .D(D), .EN(1'b0), .Q(Q[0])); // EN is never active
-(* init = "1'b1" *) wire Q1; assign Q[1] = Q1;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove1 (.CLK(C), .D(D), .EN(1'b0), .Q(Q1)); // EN is never active
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove2 (.CLK(C), .D(D), .EN(1'bx), .Q(Q[2])); // EN is don't care
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) keep3 (.CLK(C), .D(D), .EN(1'b1), .Q(Q[3])); // EN is always active
-(* init = "1'b0" *) wire Q4; assign Q[4] = Q4;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(0), .EN_POLARITY(1)) keep4 (.CLK(C), .D(D), .EN(1'b1), .Q(Q4)); // EN is always active
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove5 (.CLK(C), .D(D), .EN(1'b1), .Q(Q[5])); // EN is never active
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove6 (.CLK(C), .D(D), .EN(1'bx), .Q(Q[6])); // EN is don't care
-(* init = "1'b0" *) wire Q7; assign Q[7] = Q7;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(0), .EN_POLARITY(0)) keep7 (.CLK(C), .D(D), .EN(E), .Q(Q7)); // EN is non constant
-
-\$_DFFE_PP_ remove8 (.C(C), .D(D), .E(1'b0), .Q(Q[8])); // EN is never active
-(* init = "1'b1" *) wire Q9; assign Q[9] = Q9;
-\$_DFFE_PP_ remove9 (.C(C), .D(D), .E(1'b0), .Q(Q9)); // EN is never active
-\$_DFFE_PP_ remove10 (.C(C), .D(D), .E(1'bx), .Q(Q[10])); // EN is don't care
-\$_DFFE_PP_ keep11 (.C(C), .D(D), .E(1'b1), .Q(Q[11])); // EN is always active
-(* init = "1'b0" *) wire Q12; assign Q[12] = Q12;
-\$_DFFE_PP_ keep12 (.C(C), .D(D), .E(1'b1), .Q(Q12)); // EN is always active
-
-\$_DFFE_NN_ remove13 (.C(C), .D(D), .E(1'b1), .Q(Q[13])); // EN is never active
-(* init = "1'b1" *) wire Q14; assign Q[14] = Q14;
-\$_DFFE_NN_ remove14 (.C(C), .D(D), .E(1'b1), .Q(Q14)); // EN is never active
-\$_DFFE_NN_ remove15 (.C(C), .D(D), .E(1'bx), .Q(Q[15])); // EN is don't care
-\$_DFFE_NN_ keep16 (.C(C), .D(D), .E(1'b0), .Q(Q[16])); // EN is always active
-(* init = "1'b0" *) wire Q17; assign Q[17] = Q17;
-\$_DFFE_NN_ keep17 (.C(C), .D(D), .E(1'b0), .Q(Q17)); // EN is always active
-
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove18 (.CLK(1'b0), .D(D), .EN(E), .Q(Q[18])); // CLK is constant
-(* init = "1'b1" *) wire Q19; assign Q[19] = Q19;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove19 (.CLK(1'b1), .D(D), .EN(E), .Q(Q19)); // CLK is constant
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove20 (.CLK(C), .D(1'bx), .EN(E), .Q(Q[20])); // D is undriven, Q has no initial value
-(* init = "1'b0" *) wire Q21; assign Q[21] = Q21;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) keep21 (.CLK(C), .D(1'bx), .EN(E), .Q(Q21)); // D is undriven, Q has initial value
-//\$dffe #(.WIDTH(1), .CLK_POLARITY(0), .EN_POLARITY(1)) remove22 (.CLK(C), .D(1'b0), .EN(1'b1), .Q(Q[22])); // D is constant, no initial Q value, EN is always active
-// // (TODO, Q starts with 1'bx and becomes 1'b0)
-(* init = "1'b0" *) wire Q23; assign Q[23] = Q23;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) noenable23 (.CLK(C), .D(1'b0), .EN(1'b1), .Q(Q23)); // D is constant, initial Q value same as D, EN is always active
-(* init = "1'b1" *) wire Q24; assign Q[24] = Q24;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) keep24 (.CLK(C), .D(1'b0), .EN(1'b0), .Q(Q24)); // D is constant, initial Q value NOT same as D, EN is always active
-(* init = "1'b1" *) wire Q25; assign Q[25] = Q25;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove25 (.CLK(C), .D(1'b0), .EN(1'b1), .Q(Q25)); // D is constant, EN is never active
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) remove26 (.CLK(C), .D(Q[26]), .EN(1'b1), .Q(Q[26])); // D is Q, EN is always active
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove27 (.CLK(C), .D(Q[27]), .EN(1'b1), .Q(Q[27])); // D is Q, EN is never active, but no initial value
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(0)) remove28 (.CLK(C), .D(Q[28]), .EN(E), .Q(Q[28])); // EN is nonconst, but no initial value
-(* init = "1'b1" *) wire Q29; assign Q[29] = Q29;
-\$dffe #(.WIDTH(1), .CLK_POLARITY(1), .EN_POLARITY(1)) keep29 (.CLK(C), .D(Q[29]), .EN(1'b1), .Q(Q29)); // EN is always active, but with initial value
-
-endmodule
+++ /dev/null
-read_verilog -icells opt_rmdff.v
-prep
-design -stash gold
-read_verilog -icells opt_rmdff.v
-proc
-opt_rmdff
-
-select -assert-count 0 c:remove*
-select -assert-min 7 c:keep*
-select -assert-count 0 t:$dffe 7:$_DFFE_* %u c:noenable* %i
-
-design -stash gate
-
-design -import gold -as gold
-design -import gate -as gate
-
-equiv_make gold gate equiv
-hierarchy -top equiv
-equiv_simple -undef
-equiv_status -assert
-
-design -load gold
-stat
-
-design -load gate
-stat