From 776479d7aa6448cc06c9105b11acdeb24b6e85fe Mon Sep 17 00:00:00 2001
From: williamzhu17 <williammzhu@gmail.com>
Date: Tue, 1 Apr 2025 17:17:39 -0700
Subject: [PATCH] wip tests

---
 tests/silimate/extract_reduce_gates.ys | 862 +++++++++++++++++++++++++
 tests/silimate/extract_reduce_muxes.ys | 440 +++++++++++++
 2 files changed, 1302 insertions(+)
 create mode 100644 tests/silimate/extract_reduce_gates.ys
 create mode 100644 tests/silimate/extract_reduce_muxes.ys

diff --git a/tests/silimate/extract_reduce_gates.ys b/tests/silimate/extract_reduce_gates.ys
new file mode 100644
index 000000000..c3a505651
--- /dev/null
+++ b/tests/silimate/extract_reduce_gates.ys
@@ -0,0 +1,862 @@
+###################################################################
+# Extract Reduce AND Gates Tests
+###################################################################
+
+log -header "Simple AND chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] a,
+  output wire x
+);
+  assign x = a[0] & a[1] & a[2] & a[3];
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$and
+select -assert-count 1 t:$reduce_and
+select -assert-count 1 t:$reduce_and r:A_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "AND chain with constants"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [2:0] a,
+  output wire x
+);
+  assign x = a[0] & a[1] & a[2] & 1'b1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$and
+select -assert-count 1 t:$reduce_and
+select -assert-count 1 t:$reduce_and r:A_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "AND chain with multiple branches"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [5:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3;
+
+  assign w0 = a[0] & a[1];
+  assign w1 = a[2] & a[3];
+  assign w2 = a[4] & a[5];
+  assign w3 = w0 & w1;
+  assign x = w2 & w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$and
+select -assert-count 1 t:$reduce_and
+select -assert-count 1 t:$reduce_and r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain for AND"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = a[0] & a[1];
+  assign w1 = w0 & a[2];
+  assign w2 = w1 & a[3];
+  assign x = w2 & a[4];
+
+  // Off-chain use of w1
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_and
+select -assert-count 2 t:$reduce_and
+
+# Check that both gates are 3 bits wide
+select -assert-none t:$reduce_and r:A_WIDTH!=3 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Allow off-chain for AND"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = a[0] & a[1];
+  assign w1 = w0 & a[2];
+  assign w2 = w1 & a[3];
+  assign x = w2 & a[4];
+
+  // Off-chain use of w1
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_and
+
+# Check that only one gate has a width of 5 and one gate has a width of 3
+select -assert-count 1 t:$reduce_and r:A_WIDTH=5 %i
+select -assert-count 1 t:$reduce_and r:A_WIDTH=3 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain with branches for AND"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [10:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0;
+
+  assign w0 = a[0] & a[1] & a[2] & (a[3] & a[4]) & a[5];
+  assign x  = w0 & a[6] & a[7] & (a[8] & a[9]) & a[10];
+
+  // Off-chain use of w0
+  assign y = w0;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_and
+
+# Check that both gates are 6 bits wide
+select -assert-none t:$reduce_and r:A_WIDTH!=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Allow off-chain with branches for AND"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [10:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0;
+
+  assign w0 = a[0] & a[1] & a[2] & (a[3] & a[4]) & a[5];
+  assign x  = w0 & a[6] & a[7] & (a[8] & a[9]) & a[10];
+
+  // Off-chain use of w0
+  assign y = w0;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_and
+
+# Check that only one gate has a width of 11 and one gate has a width of 6
+select -assert-count 1 t:$reduce_and r:A_WIDTH=11 %i
+select -assert-count 1 t:$reduce_and r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+###################################################################
+# Extract Reduce OR Gates Tests
+###################################################################
+
+log -header "Simple OR chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] a,
+  output wire x
+);
+  assign x = a[0] | a[1] | a[2] | a[3];
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$or
+select -assert-count 1 t:$reduce_or
+select -assert-count 1 t:$reduce_or r:A_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "OR chain with constants"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] a,
+  output wire x
+);
+  assign x = a[0] | a[1] | a[2] | 1'b1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$or
+select -assert-count 1 t:$reduce_or
+select -assert-count 1 t:$reduce_or r:A_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "OR chain with multiple branches"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [5:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3;
+
+  assign w0 = a[0] | a[1];
+  assign w1 = a[2] | a[3];
+  assign w2 = a[4] | a[5];
+  assign w3 = w0 | w1;
+  assign x = w2 | w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$or
+select -assert-count 1 t:$reduce_or
+select -assert-count 1 t:$reduce_or r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain OR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = a[0] | a[1];
+  assign w1 = w0 | a[2];
+  assign w2 = w1 | a[3];
+  assign x = w2 | a[4];
+
+  // Off-chain use of w1
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$or
+select -assert-count 2 t:$reduce_or
+
+# Check that both gates are 3 bits wide
+select -assert-none t:$reduce_or r:A_WIDTH!=3 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Allow off-chain for OR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = a[0] | a[1];
+  assign w1 = w0 | a[2];
+  assign w2 = w1 | a[3];
+  assign x = w2 | a[4];
+
+  // Off-chain use of w1
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$or
+select -assert-count 2 t:$reduce_or
+
+# Check that only one gate has a width of 5 and one gate has a width of 3
+select -assert-count 1 t:$reduce_or r:A_WIDTH=5 %i
+select -assert-count 1 t:$reduce_or r:A_WIDTH=3 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain with branches for OR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [10:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0;
+
+  assign w0 = a[0] | a[1] | a[2] | (a[3] | a[4]) | a[5];
+  assign x  = w0 | a[6] | a[7] | (a[8] | a[9]) | a[10];
+
+  // Off-chain use of w0
+  assign y = w0;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_or
+
+# Check that both gates are 6 bits wide
+select -assert-none t:$reduce_or r:A_WIDTH!=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Allow off-chain with branches for OR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [10:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0;
+
+  assign w0 = a[0] | a[1] | a[2] | (a[3] | a[4]) | a[5];
+  assign x  = w0 | a[6] | a[7] | (a[8] | a[9]) | a[10];
+
+  // Off-chain use of w0
+  assign y = w0;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$or
+select -assert-count 2 t:$reduce_or
+
+# Check that only one gate has a width of 11 and one gate has a width of 6
+select -assert-count 1 t:$reduce_or r:A_WIDTH=11 %i
+select -assert-count 1 t:$reduce_or r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+###################################################################
+# Extract Reduce XOR Gates Tests
+###################################################################
+
+log -header "Simple XOR chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] a,
+  output wire x
+);
+  assign x = a[0] ^ a[1] ^ a[2] ^ a[3];
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$xor
+select -assert-count 1 t:$reduce_xor
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "XOR chain with constants"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] a,
+  output wire x
+);
+  assign x = a[0] ^ a[1] ^ a[2] ^ 1'b1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$xor
+select -assert-count 1 t:$reduce_xor
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "XOR chain with multiple branches"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [5:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3;
+
+  assign w0 = a[0] ^ a[1];
+  assign w1 = a[2] ^ a[3];
+  assign w2 = a[4] ^ a[5];
+  assign w3 = w0 ^ w1;
+  assign x = w2 ^ w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$xor
+select -assert-count 1 t:$reduce_xor
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain XOR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = a[0] ^ a[1];
+  assign w1 = w0 ^ a[2];
+  assign w2 = w1 ^ a[3];
+  assign x = w2 ^ a[4];
+
+  // Off-chain use of w1
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$xor
+select -assert-count 2 t:$reduce_xor
+
+# Check that both gates are 3 bits wide
+select -assert-none t:$reduce_xor r:A_WIDTH!=3 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Allow off-chain for XOR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = a[0] ^ a[1];
+  assign w1 = w0 ^ a[2];
+  assign w2 = w1 ^ a[3];
+  assign x = w2 ^ a[4];
+
+  // Off-chain use of w1
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$xor
+select -assert-count 2 t:$reduce_xor
+
+# Check that only one gate has a width of 5 and one gate has a width of 3
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=5 %i
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=3 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain with branches for XOR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [10:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0;
+
+  assign w0 = a[0] ^ a[1] ^ a[2] ^ (a[3] ^ a[4]) ^ a[5];
+  assign x  = w0 ^ a[6] ^ a[7] ^ (a[8] ^ a[9]) ^ a[10];
+
+  // Off-chain use of w0
+  assign y = w0;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$xor
+select -assert-count 2 t:$reduce_xor
+
+# Check that both gates are 6 bits wide
+select -assert-none t:$reduce_xor r:A_WIDTH!=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Allow off-chain with branches for XOR"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [10:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0;
+
+  assign w0 = a[0] ^ a[1] ^ a[2] ^ (a[3] ^ a[4]) ^ a[5];
+  assign x  = w0 ^ a[6] ^ a[7] ^ (a[8] ^ a[9]) ^ a[10];
+
+  // Off-chain use of w0
+  assign y = w0;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates
+select -assert-count 0 t:$xor
+select -assert-count 2 t:$reduce_xor
+
+# Check that only one gate has a width of 11 and one gate has a width of 6
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=11 %i
+select -assert-count 1 t:$reduce_xor r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+###################################################################
+# Edge Cases
+###################################################################
+
+log -header "Reconvergence"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input  wire [7:0] a,
+  output wire y
+);
+  wire w0, w1, w2, w3, w4, w5, w6;
+
+  assign w0 = a[0] & a[1];
+  assign w1 = a[2] & a[3];
+  assign w2 = w0 & w1;
+  assign w3 = w2 & a[4];
+  assign w4 = w2 & a[5];
+  assign w5 = w3 & a[6];
+  assign w6 = w4 & a[7];
+  assign y = w5 & w6;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_and
+select -assert-count 1 t:$reduce_and r:A_WIDTH=4 %i
+select -assert-count 1 t:$reduce_and r:A_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+# TODO
+log -header "Combinational feedback loop"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input  wire a,
+  output wire y
+);
+  wire w0, w1;
+
+  // Two AND gates feeding each other
+  assign w0 = a & w1;
+  assign w1 = a & w0;
+
+  assign y = w1;
+endmodule
+EOF
+# check -assert
+
+# Check equivalence after extract_reduce
+# equiv_opt -assert extract_reduce
+extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check final design has correct number of gates and inputs
+select -assert-count 0 t:$and
+select -assert-count 2 t:$reduce_and
+select -assert-count 1 t:$reduce_and r:A_WIDTH=4 %i
+select -assert-count 1 t:$reduce_and r:A_WIDTH=6 %i
+
+design -reset
+log -pop
\ No newline at end of file
diff --git a/tests/silimate/extract_reduce_muxes.ys b/tests/silimate/extract_reduce_muxes.ys
new file mode 100644
index 000000000..b5cd3b2a1
--- /dev/null
+++ b/tests/silimate/extract_reduce_muxes.ys
@@ -0,0 +1,440 @@
+log -header "Simple MUX chain to PMUX"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [2:0] sel,
+  input wire [3:0] a,
+  output wire x
+);
+  wire w0, w1;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign x  = sel[2] ? a[3] : w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check we got a single pmux with the correct input number
+select -assert-count 0 t:$mux
+select -assert-count 1 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "MUX chain with constants"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [2:0] sel,
+  input wire [2:0] a,
+  output wire x
+);
+  wire w0, w1;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign x  = sel[2] ? 1'b1 : w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check we got a single pmux with the correct input number
+select -assert-count 0 t:$mux
+select -assert-count 1 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "MUX chain with multiple branches"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [2:0] sel,
+  input wire [3:0] a,
+  output wire x
+);
+  wire w0, w1;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : a[3];
+  assign x  = sel[2] ? w0 : w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check we got a single pmux with the correct input number
+select -assert-count 0 t:$mux
+select -assert-count 1 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=4 %i
+
+design -reset
+log -pop
+
+
+
+log -header "MUX chain with multiple uneven branches"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [5:0] sel,
+  input wire [6:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3, w4;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? a[3] : w1;
+  assign w3 = sel[3] ? w2 : w4;
+  assign w4 = sel[5] ? a[4] : a[5];
+  assign x  = sel[4] ? w3 : a[6];
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check we got a single pmux with the correct input number
+select -assert-count 0 t:$mux
+select -assert-count 1 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=7 %i
+
+design -reset
+log -pop
+
+
+
+log -header "No off-chain MUX chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] sel,
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? a[3] : w1;
+  assign x  = sel[3] ? a[4] : w2;
+
+  // Off-chain use of intermediate wire
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check we got two pmuxes
+select -assert-count 0 t:$mux
+select -assert-count 2 t:$pmux
+
+# Check that both pmuxes have input width of 3
+select -assert-none t:$pmux r:S_WIDTH!=3 %i
+
+design -reset
+log -pop
+
+
+
+
+log -header "Allow off-chain MUX chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [3:0] sel,
+  input wire [4:0] a,
+  output wire x,
+  output wire y
+);
+  wire w0, w1, w2;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? a[3] : w1;
+  assign x  = sel[3] ? a[4] : w2;
+
+  assign y = w1;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean to remove unnecessary wires
+design -load postopt
+opt_clean
+
+# Check we got two pmux
+select -assert-count 0 t:$mux
+select -assert-count 2 t:$pmux
+
+# Check that one pmux has an input width of 3 
+# and the other has an input width of 5
+select -assert-count 1 t:$pmux r:S_WIDTH=3 %i
+select -assert-count 1 t:$pmux r:S_WIDTH=5 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Reconverging tree; no off-chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [7:0] sel,
+  input wire [7:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3, w4, w5, w6;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? w4 : w1;
+  assign w3 = sel[3] ? w2 : w5;
+  assign w4 = sel[6] ? a[3] : w6;
+  assign w5 = sel[5] ? a[5] : w4;
+  assign w6 = sel[7] ? a[7] : a[4];
+  assign x  = sel[4] ? a[6] : w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean and opt_reduce to remove unnecessary cells
+design -load postopt
+opt_clean
+opt_reduce
+
+# Check we got one pmux with correct number of inputs
+select -assert-count 0 t:$mux
+select -assert-count 2 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=3 %i
+select -assert-count 1 t:$pmux r:S_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Reconverging tree; yes off-chain"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [7:0] sel,
+  input wire [7:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3, w4, w5, w6;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? w4 : w1;
+  assign w3 = sel[3] ? w2 : w5;
+  assign w4 = sel[6] ? a[3] : w6;
+  assign w5 = sel[5] ? a[5] : w4;
+  assign w6 = sel[7] ? a[7] : a[4];
+  assign x  = sel[4] ? a[6] : w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce -allow-off-chain
+
+# Load design and run opt_clean and opt_reduce to remove unnecessary cells
+design -load postopt
+opt_clean
+opt_reduce
+
+# Check we got one pmux with correct number of inputs
+select -assert-count 0 t:$mux
+select -assert-count 1 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=8 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Reusing select inputs"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [5:0] sel,
+  input wire [7:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3, w4, w5, w6;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? w4 : w1;
+  assign w3 = sel[3] ? w2 : w5;
+  assign w4 = sel[2] ? a[3] : w6;
+  assign w5 = sel[5] ? a[5] : w4;
+  assign w6 = sel[4] & sel[1] ? a[7] : a[4];
+  assign x  = sel[4] ? a[6] : w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean and opt_reduce to remove unnecessary cells
+design -load postopt
+opt_clean
+opt_reduce
+
+# Check we got one pmux with correct number of inputs
+select -assert-count 0 t:$mux
+select -assert-count 2 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=3 %i
+select -assert-count 1 t:$pmux r:S_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+log -header "Using outputs as select inputs"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [5:0] sel,
+  input wire [7:0] a,
+  output wire x
+);
+  wire w0, w1, w2, w3, w4, w5, w6;
+
+  assign w0 = sel[0] ? a[1] : a[0];
+  assign w1 = sel[1] ? a[2] : w0;
+  assign w2 = sel[2] ? w4 : w1;
+  assign w3 = sel[3] ? w2 : w5;
+  assign w4 = sel[2] ? a[3] : w6;
+  assign w5 = sel[5] ? a[5] : w4;
+  assign w6 = w[2] ? a[7] : a[4];
+  assign x  = sel[4] ? a[6] : w3;
+endmodule
+EOF
+check -assert
+
+# Check equivalence after extract_reduce
+equiv_opt -assert extract_reduce
+
+# Load design and run opt_clean and opt_reduce to remove unnecessary cells
+design -load postopt
+opt_clean
+opt_reduce
+
+# Check we got one pmux with correct number of inputs
+select -assert-count 0 t:$mux
+select -assert-count 2 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=3 %i
+select -assert-count 1 t:$pmux r:S_WIDTH=6 %i
+
+design -reset
+log -pop
+
+
+
+# TODO check about infinite loop
+log -header "Mux with feedback that causes infinite loop"
+log -push
+design -reset
+read_verilog <<EOF
+module top (
+  input wire [2:0] sel,
+  input wire [3:0] a,
+  output wire x
+);
+  wire w0, w1;
+
+  assign w0 = sel[0] ? a[0] : w0;
+  assign w1 = sel[1] ? a[1] : w0;
+  assign x  = sel[2] ? a[2] : w1;
+endmodule
+EOF
+# check -assert
+
+autoname
+write_json dump_pre.json
+exec -- netlistsvg dump_pre.json -o dump_pre.svg
+
+# Check equivalence after extract_reduce
+# equiv_opt -assert extract_reduce
+extract_reduce -allow-off-chain
+
+# Load design and run opt_clean and opt_reduce to remove unnecessary cells
+# design -load postopt
+opt_clean
+opt_reduce
+
+autoname
+write_json dump_post.json
+exec -- netlistsvg dump_post.json -o dump_post.svg
+
+# Check we got one pmux with correct number of inputs
+select -assert-count 0 t:$mux
+select -assert-count 2 t:$pmux
+select -assert-count 1 t:$pmux r:S_WIDTH=3 %i
+select -assert-count 1 t:$pmux r:S_WIDTH=6 %i
+
+design -reset
+log -pop
\ No newline at end of file