diff --git a/tests/csa_tree/csa_tree_add_chains.ys b/tests/csa_tree/csa_tree_add_chains.ys
index 46e5868a9..98067ce16 100644
--- a/tests/csa_tree/csa_tree_add_chains.ys
+++ b/tests/csa_tree/csa_tree_add_chains.ys
@@ -59,3 +59,176 @@ csa_tree
 select -assert-count 14 t:$fa
 select -assert-count 1 t:$add
 design -reset
+
+read_verilog <<EOT
+module alu_add3(
+	input [7:0] a, b, c,
+	output [7:0] y
+);
+	assign y = a + b + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 1 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+design -reset
+
+read_verilog <<EOT
+module alu_add4(
+	input [7:0] a, b, c, d,
+	output [7:0] y
+);
+	assign y = a + b + c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+design -reset
+
+read_verilog <<EOT
+module alu_add5(
+	input [11:0] a, b, c, d, e,
+	output [11:0] y
+);
+	assign y = a + b + c + d + e;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 3 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+design -reset
+
+read_verilog <<EOT
+module alu_add8(
+	input [15:0] a, b, c, d, e, f, g, h,
+	output [15:0] y
+);
+	assign y = a + b + c + d + e + f + g + h;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 6 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+design -reset
+
+read_verilog <<EOT
+module alu_add16(
+	input [15:0] a0, a1, a2, a3, a4, a5, a6, a7,
+	input [15:0] a8, a9, a10, a11, a12, a13, a14, a15,
+	output [15:0] y
+);
+	assign y = a0 + a1 + a2 + a3 + a4 + a5 + a6 + a7
+	+ a8 + a9 + a10 + a11 + a12 + a13 + a14 + a15;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 14 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+design -reset
+
+read_verilog <<EOT
+module macc_add3(
+	input [7:0] a, b, c,
+	output [7:0] y
+);
+	assign y = a + b + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-count 1 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$macc t:$macc_v2 %u
+design -reset
+
+read_verilog <<EOT
+module macc_add4(
+	input [7:0] a, b, c, d,
+	output [7:0] y
+);
+	assign y = a + b + c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$macc t:$macc_v2 %u
+design -reset
+
+read_verilog <<EOT
+module macc_add5(
+	input [11:0] a, b, c, d, e,
+	output [11:0] y
+);
+	assign y = a + b + c + d + e;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-count 3 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$macc t:$macc_v2 %u
+design -reset
+
+read_verilog <<EOT
+module macc_add8(
+	input [15:0] a, b, c, d, e, f, g, h,
+	output [15:0] y
+);
+	assign y = a + b + c + d + e + f + g + h;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-count 6 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$macc t:$macc_v2 %u
+design -reset
diff --git a/tests/csa_tree/csa_tree_alu_chains.ys b/tests/csa_tree/csa_tree_alu_chains.ys
deleted file mode 100644
index ada1368dc..000000000
--- a/tests/csa_tree/csa_tree_alu_chains.ys
+++ /dev/null
@@ -1,96 +0,0 @@
-read_verilog <<EOT
-module alu_add3(
-	input [7:0] a, b, c,
-	output [7:0] y
-);
-	assign y = a + b + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 1 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_add4(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 2 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_add5(
-	input [11:0] a, b, c, d, e,
-	output [11:0] y
-);
-	assign y = a + b + c + d + e;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 3 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_add8(
-	input [15:0] a, b, c, d, e, f, g, h,
-	output [15:0] y
-);
-	assign y = a + b + c + d + e + f + g + h;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 6 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_add16(
-	input [15:0] a0, a1, a2, a3, a4, a5, a6, a7,
-	input [15:0] a8, a9, a10, a11, a12, a13, a14, a15,
-	output [15:0] y
-);
-	assign y = a0 + a1 + a2 + a3 + a4 + a5 + a6 + a7
-	+ a8 + a9 + a10 + a11 + a12 + a13 + a14 + a15;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 14 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-design -reset
diff --git a/tests/csa_tree/csa_tree_alu_macc_edge_cases.ys b/tests/csa_tree/csa_tree_alu_macc_edge_cases.ys
deleted file mode 100644
index 6751a58ed..000000000
--- a/tests/csa_tree/csa_tree_alu_macc_edge_cases.ys
+++ /dev/null
@@ -1,285 +0,0 @@
-read_verilog <<EOT
-module alu_add2(
-	input [7:0] a, b,
-	output [7:0] y
-);
-	assign y = a + b;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-select -assert-none t:$fa
-select -assert-none t:$add
-select -assert-none t:$sub
-select -assert-count 1 t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_sub2(
-	input [7:0] a, b,
-	output [7:0] y
-);
-	assign y = a - b;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-select -assert-none t:$fa
-select -assert-none t:$add
-select -assert-none t:$sub
-select -assert-count 1 t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_compare(
-	input [7:0] a, b,
-	output y
-);
-	assign y = (a < b);
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-select -assert-none t:$fa
-select -assert-none t:$add
-select -assert-none t:$sub
-select -assert-count 1 t:$alu
-design -reset
-
-read_verilog <<EOT
-module macc_mul(
-	input [7:0] a, b, c,
-	output [15:0] y
-);
-	assign y = a * b + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-none t:$fa
-select -assert-min 1 t:$macc t:$macc_v2 %u
-design -reset
-
-read_verilog <<EOT
-module alu_fanout(
-	input [7:0] a, b, c,
-	output [7:0] mid, y
-);
-	wire [7:0] ab = a + b;
-	assign mid = ab;
-	assign y = ab + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-none t:$fa
-select -assert-count 2 t:$alu
-design -reset
-
-read_verilog <<EOT
-module macc_2port(
-	input [7:0] a, b,
-	output [7:0] y
-);
-	assign y = a + b;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-none t:$fa
-design -reset
-
-read_verilog <<EOT
-module alu_idempotent(
-	input [15:0] a, b, c, d, e, f, g, h,
-	output [15:0] y
-);
-	assign y = a + b + c + d + e + f + g + h;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-
-csa_tree
-select -assert-count 6 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$sub
-select -assert-none t:$alu
-
-csa_tree
-select -assert-count 6 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$sub
-select -assert-none t:$alu
-design -reset
-
-read_verilog <<EOT
-module alu_mixed_width(
-	input [7:0] a,
-	input [3:0] b,
-	input [15:0] c,
-	input [7:0] d,
-	output [15:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 2 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module alu_signed(
-	input signed [7:0] a, b, c, d,
-	output signed [9:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 2 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module fir_4tap_alu(
-	input clk,
-	input [15:0] x, c0, c1, c2, c3,
-	output reg [31:0] y
-);
-	reg [15:0] x1, x2, x3;
-	always @(posedge clk) begin
-		x1 <= x;
-		x2 <= x1;
-		x3 <= x2;
-	end
-
-	wire [31:0] sum = x*c0 + x1*c1 + x2*c2 + x3*c3;
-	always @(posedge clk) y <= sum;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-min 1 t:$dff
-design -reset
-
-read_verilog <<EOT
-module alu_mixed_sign(
-	input signed [7:0] a,
-	input [7:0] b,
-	input signed [7:0] c,
-	output signed [9:0] y
-);
-	assign y = a + b + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 1 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module alu_wide32(
-	input [31:0] a, b, c, d,
-	output [31:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 2 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module alu_single(
-	input [7:0] a,
-	output [7:0] y
-);
-	assign y = a;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-select -assert-none t:$fa
-select -assert-none t:$add
-select -assert-none t:$sub
-select -assert-none t:$alu
-design -reset
-
-read_verilog <<EOT
-module macc_mul_survives(
-	input [7:0] a, b, c, d,
-	output [15:0] y
-);
-	assign y = a * b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-none t:$fa
-select -assert-min 1 t:$macc t:$macc_v2 %u
-design -reset
diff --git a/tests/csa_tree/csa_tree_alu_macc_equiv.ys b/tests/csa_tree/csa_tree_alu_macc_equiv.ys
index a8c60ac1a..b698aa43d 100644
--- a/tests/csa_tree/csa_tree_alu_macc_equiv.ys
+++ b/tests/csa_tree/csa_tree_alu_macc_equiv.ys
@@ -177,3 +177,21 @@ design -load postopt
 select -assert-count 2 t:$fa
 select -assert-count 1 t:$add
 design -reset
+
+read_verilog <<EOT
+module equiv_macc_sub_mixed(
+	input [3:0] a, b, c, d,
+	output [3:0] y
+);
+	assign y = a + b - c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+equiv_opt csa_tree
+design -load postopt
+select -assert-min 1 t:$fa
+select -assert-count 1 t:$add
+design -reset
diff --git a/tests/csa_tree/csa_tree_alu_macc_sim.ys b/tests/csa_tree/csa_tree_alu_macc_sim.ys
deleted file mode 100644
index 7f76ac476..000000000
--- a/tests/csa_tree/csa_tree_alu_macc_sim.ys
+++ /dev/null
@@ -1,116 +0,0 @@
-read_verilog <<EOT
-module sim_alu_add4(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-
-sat -set a 1 -set b 2 -set c 3 -set d 4 -prove y 10
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 255 -set b 1 -set c 0 -set d 0 -prove y 0
-sat -set a 100 -set b 50 -set c 25 -set d 25 -prove y 200
-sat -set a 255 -set b 255 -set c 255 -set d 255 -prove y 252
-design -reset
-
-read_verilog <<EOT
-module sim_alu_sub_mixed(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b - c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-
-sat -set a 10 -set b 20 -set c 5 -set d 3 -prove y 28
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 100 -set b 50 -set c 30 -set d 10 -prove y 130
-design -reset
-
-read_verilog <<EOT
-module sim_alu_sub_all(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a - b - c - d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-
-sat -set a 100 -set b 10 -set c 20 -set d 30 -prove y 40
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 255 -set b 1 -set c 1 -set d 1 -prove y 252
-design -reset
-
-read_verilog <<EOT
-module sim_macc_add4(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-
-sat -set a 1 -set b 2 -set c 3 -set d 4 -prove y 10
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 255 -set b 1 -set c 0 -set d 0 -prove y 0
-sat -set a 100 -set b 50 -set c 25 -set d 25 -prove y 200
-design -reset
-
-read_verilog <<EOT
-module sim_macc_add8(
-	input [7:0] a, b, c, d, e, f, g, h,
-	output [7:0] y
-);
-	assign y = a + b + c + d + e + f + g + h;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-
-sat -set a 1 -set b 2 -set c 3 -set d 4 -set e 5 -set f 6 -set g 7 -set h 8 -prove y 36
-sat -set a 0 -set b 0 -set c 0 -set d 0 -set e 0 -set f 0 -set g 0 -set h 0 -prove y 0
-sat -set a 32 -set b 32 -set c 32 -set d 32 -set e 32 -set f 32 -set g 32 -set h 32 -prove y 0
-design -reset
-
-read_verilog <<EOT
-module sim_macc_sub_mixed(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b - c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-
-sat -set a 10 -set b 20 -set c 5 -set d 3 -prove y 28
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 100 -set b 50 -set c 30 -set d 10 -prove y 130
-design -reset
diff --git a/tests/csa_tree/csa_tree_alu_sub_chains.ys b/tests/csa_tree/csa_tree_alu_sub_chains.ys
deleted file mode 100644
index c7ff5663a..000000000
--- a/tests/csa_tree/csa_tree_alu_sub_chains.ys
+++ /dev/null
@@ -1,79 +0,0 @@
-read_verilog <<EOT
-module alu_sub_3op(
-	input [7:0] a, b, c,
-	output [7:0] y
-);
-	assign y = a - b + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 2 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module alu_sub_mixed(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b - c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 3 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module alu_sub_all(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a - b - c - d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 3 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
-
-read_verilog <<EOT
-module alu_sub_signed(
-	input signed [7:0] a, b, c, d,
-	output signed [9:0] y
-);
-	assign y = a + b - c - d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt_clean
-csa_tree
-opt_clean
-select -assert-count 3 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$alu
-select -assert-none t:$sub
-design -reset
diff --git a/tests/csa_tree/csa_tree_edge_cases.ys b/tests/csa_tree/csa_tree_edge_cases.ys
index 1031f6c2c..e77f10bf2 100644
--- a/tests/csa_tree/csa_tree_edge_cases.ys
+++ b/tests/csa_tree/csa_tree_edge_cases.ys
@@ -145,3 +145,263 @@ csa_tree
 select -assert-count 2 t:$fa
 select -assert-count 1 t:$add
 design -reset
+
+read_verilog <<EOT
+module alu_add2(
+	input [7:0] a, b,
+	output [7:0] y
+);
+	assign y = a + b;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+select -assert-none t:$fa
+select -assert-none t:$add
+select -assert-none t:$sub
+select -assert-count 1 t:$alu
+design -reset
+
+read_verilog <<EOT
+module alu_sub2(
+	input [7:0] a, b,
+	output [7:0] y
+);
+	assign y = a - b;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+select -assert-none t:$fa
+select -assert-none t:$add
+select -assert-none t:$sub
+select -assert-count 1 t:$alu
+design -reset
+
+read_verilog <<EOT
+module alu_compare(
+	input [7:0] a, b,
+	output y
+);
+	assign y = (a < b);
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+select -assert-none t:$fa
+select -assert-none t:$add
+select -assert-none t:$sub
+select -assert-count 1 t:$alu
+design -reset
+
+read_verilog <<EOT
+module macc_mul(
+	input [7:0] a, b, c,
+	output [15:0] y
+);
+	assign y = a * b + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-none t:$fa
+select -assert-min 1 t:$macc t:$macc_v2 %u
+design -reset
+
+read_verilog <<EOT
+module alu_fanout(
+	input [7:0] a, b, c,
+	output [7:0] mid, y
+);
+	wire [7:0] ab = a + b;
+	assign mid = ab;
+	assign y = ab + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-none t:$fa
+select -assert-count 2 t:$alu
+design -reset
+
+read_verilog <<EOT
+module macc_2port(
+	input [7:0] a, b,
+	output [7:0] y
+);
+	assign y = a + b;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-none t:$fa
+design -reset
+
+read_verilog <<EOT
+module alu_mixed_width(
+	input [7:0] a,
+	input [3:0] b,
+	input [15:0] c,
+	input [7:0] d,
+	output [15:0] y
+);
+	assign y = a + b + c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_signed(
+	input signed [7:0] a, b, c, d,
+	output signed [9:0] y
+);
+	assign y = a + b + c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module fir_4tap_alu(
+	input clk,
+	input [15:0] x, c0, c1, c2, c3,
+	output reg [31:0] y
+);
+	reg [15:0] x1, x2, x3;
+	always @(posedge clk) begin
+		x1 <= x;
+		x2 <= x1;
+		x3 <= x2;
+	end
+
+	wire [31:0] sum = x*c0 + x1*c1 + x2*c2 + x3*c3;
+	always @(posedge clk) y <= sum;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-min 1 t:$dff
+design -reset
+
+read_verilog <<EOT
+module alu_mixed_sign(
+	input signed [7:0] a,
+	input [7:0] b,
+	input signed [7:0] c,
+	output signed [9:0] y
+);
+	assign y = a + b + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 1 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_wide32(
+	input [31:0] a, b, c, d,
+	output [31:0] y
+);
+	assign y = a + b + c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_single(
+	input [7:0] a,
+	output [7:0] y
+);
+	assign y = a;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+select -assert-none t:$fa
+select -assert-none t:$add
+select -assert-none t:$sub
+select -assert-none t:$alu
+design -reset
+
+read_verilog <<EOT
+module macc_mul_survives(
+	input [7:0] a, b, c, d,
+	output [15:0] y
+);
+	assign y = a * b + c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-none t:$fa
+select -assert-min 1 t:$macc t:$macc_v2 %u
+design -reset
diff --git a/tests/csa_tree/csa_tree_equiv.ys b/tests/csa_tree/csa_tree_equiv.ys
index e208af6c8..966f8ccff 100644
--- a/tests/csa_tree/csa_tree_equiv.ys
+++ b/tests/csa_tree/csa_tree_equiv.ys
@@ -96,6 +96,22 @@ select -assert-count 1 t:$fa
 select -assert-count 1 t:$add
 design -reset
 
+read_verilog <<EOT
+module equiv_sub_3op(
+	input [3:0] a, b, c,
+	output [3:0] y
+);
+	assign y = a - b + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+equiv_opt csa_tree
+design -load postopt
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+design -reset
+
 read_verilog <<EOT
 module equiv_sub_mixed(
 	input [3:0] a, b, c, d,
@@ -108,7 +124,7 @@ hierarchy -auto-top
 proc
 equiv_opt csa_tree
 design -load postopt
-select -assert-count 3 t:$fa
+select -assert-min 1 t:$fa
 select -assert-count 1 t:$add
 design -reset
 
@@ -124,23 +140,7 @@ hierarchy -auto-top
 proc
 equiv_opt csa_tree
 design -load postopt
-select -assert-count 3 t:$fa
-select -assert-count 1 t:$add
-design -reset
-
-read_verilog <<EOT
-module equiv_sub_3op(
-	input [3:0] a, b, c,
-	output [3:0] y
-);
-	assign y = a - b + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-equiv_opt csa_tree
-design -load postopt
-select -assert-count 2 t:$fa
+select -assert-min 1 t:$fa
 select -assert-count 1 t:$add
 design -reset
 
diff --git a/tests/csa_tree/csa_tree_idempotent.ys b/tests/csa_tree/csa_tree_idempotent.ys
index dfe098597..1e2fe888a 100644
--- a/tests/csa_tree/csa_tree_idempotent.ys
+++ b/tests/csa_tree/csa_tree_idempotent.ys
@@ -17,3 +17,30 @@ csa_tree
 select -assert-count 6 t:$fa
 select -assert-count 1 t:$add
 select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_idempotent(
+	input [15:0] a, b, c, d, e, f, g, h,
+	output [15:0] y
+);
+	assign y = a + b + c + d + e + f + g + h;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+
+csa_tree
+select -assert-count 6 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$sub
+select -assert-none t:$alu
+
+csa_tree
+select -assert-count 6 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$sub
+select -assert-none t:$alu
+design -reset
diff --git a/tests/csa_tree/csa_tree_macc.ys b/tests/csa_tree/csa_tree_macc.ys
deleted file mode 100644
index 4c2490e34..000000000
--- a/tests/csa_tree/csa_tree_macc.ys
+++ /dev/null
@@ -1,133 +0,0 @@
-read_verilog <<EOT
-module macc_add3(
-	input [7:0] a, b, c,
-	output [7:0] y
-);
-	assign y = a + b + c;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-count 1 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$macc t:$macc_v2 %u
-design -reset
-
-read_verilog <<EOT
-module macc_add4(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-count 2 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$macc t:$macc_v2 %u
-design -reset
-
-read_verilog <<EOT
-module macc_add5(
-	input [11:0] a, b, c, d, e,
-	output [11:0] y
-);
-	assign y = a + b + c + d + e;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-count 3 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$macc t:$macc_v2 %u
-design -reset
-
-read_verilog <<EOT
-module macc_add8(
-	input [15:0] a, b, c, d, e, f, g, h,
-	output [15:0] y
-);
-	assign y = a + b + c + d + e + f + g + h;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-count 6 t:$fa
-select -assert-count 1 t:$add
-select -assert-none t:$macc t:$macc_v2 %u
-design -reset
-
-read_verilog <<EOT
-module macc_sub_mixed(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b - c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-none t:$macc t:$macc_v2 %u
-select -assert-min 1 t:$fa
-select -assert-count 1 t:$add
-design -reset
-
-read_verilog <<EOT
-module macc_const(
-	input [7:0] a, b, c,
-	output [7:0] y
-);
-	assign y = a + b + c + 8'd42;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-none t:$macc t:$macc_v2 %u
-select -assert-min 1 t:$fa
-select -assert-count 1 t:$add
-design -reset
-
-read_verilog <<EOT
-module macc_two(
-	input [7:0] a, b, c, d, e, f, g, h,
-	output [7:0] y1, y2
-);
-	assign y1 = a + b + c + d;
-	assign y2 = e + f + g + h;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-alumacc
-opt
-csa_tree
-opt_clean
-select -assert-none t:$macc t:$macc_v2 %u
-select -assert-count 4 t:$fa
-select -assert-count 2 t:$add
-design -reset
diff --git a/tests/csa_tree/csa_tree_sim.ys b/tests/csa_tree/csa_tree_sim.ys
deleted file mode 100644
index 7f6cbd1c8..000000000
--- a/tests/csa_tree/csa_tree_sim.ys
+++ /dev/null
@@ -1,72 +0,0 @@
-read_verilog <<EOT
-module sim_add4(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b + c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-csa_tree
-
-sat -set a 1 -set b 2 -set c 3 -set d 4 -prove y 10
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 255 -set b 1 -set c 0 -set d 0 -prove y 0
-sat -set a 100 -set b 50 -set c 25 -set d 25 -prove y 200
-sat -set a 255 -set b 255 -set c 255 -set d 255 -prove y 252
-design -reset
-
-read_verilog <<EOT
-module sim_sub_mixed(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a + b - c + d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-csa_tree
-
-sat -set a 10 -set b 20 -set c 5 -set d 3 -prove y 28
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 100 -set b 50 -set c 30 -set d 10 -prove y 130
-sat -set a 1 -set b 1 -set c 255 -set d 1 -prove y 4
-design -reset
-
-read_verilog <<EOT
-module sim_sub_all(
-	input [7:0] a, b, c, d,
-	output [7:0] y
-);
-	assign y = a - b - c - d;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-csa_tree
-
-sat -set a 100 -set b 10 -set c 20 -set d 30 -prove y 40
-sat -set a 0 -set b 0 -set c 0 -set d 0 -prove y 0
-sat -set a 255 -set b 1 -set c 1 -set d 1 -prove y 252
-design -reset
-
-read_verilog <<EOT
-module sim_double_neg(
-	input [7:0] a, b, c,
-	output [7:0] y
-);
-	wire [7:0] ab = a - b;
-	assign y = c - ab;
-endmodule
-EOT
-hierarchy -auto-top
-proc
-csa_tree
-
-sat -set a 30 -set b 20 -set c 10 -prove y 0
-sat -set a 50 -set b 25 -set c 100 -prove y 75
-sat -set a 0 -set b 0 -set c 0 -prove y 0
-sat -set a 255 -set b 1 -set c 1 -prove y 3
-design -reset
diff --git a/tests/csa_tree/csa_tree_sub_chains.ys b/tests/csa_tree/csa_tree_sub_chains.ys
index 7f7ac1c34..b63eb16ac 100644
--- a/tests/csa_tree/csa_tree_sub_chains.ys
+++ b/tests/csa_tree/csa_tree_sub_chains.ys
@@ -100,3 +100,141 @@ select -assert-count 1 t:$add
 select -assert-count 1 t:$not
 select -assert-none t:$sub
 design -reset
+
+read_verilog <<EOT
+module alu_sub_3op(
+	input [7:0] a, b, c,
+	output [7:0] y
+);
+	assign y = a - b + c;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 2 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_sub_mixed(
+	input [7:0] a, b, c, d,
+	output [7:0] y
+);
+	assign y = a + b - c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 3 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_sub_all(
+	input [7:0] a, b, c, d,
+	output [7:0] y
+);
+	assign y = a - b - c - d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 3 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module alu_sub_signed(
+	input signed [7:0] a, b, c, d,
+	output signed [9:0] y
+);
+	assign y = a + b - c - d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt_clean
+csa_tree
+opt_clean
+select -assert-count 3 t:$fa
+select -assert-count 1 t:$add
+select -assert-none t:$alu
+select -assert-none t:$sub
+design -reset
+
+read_verilog <<EOT
+module macc_sub_mixed(
+	input [7:0] a, b, c, d,
+	output [7:0] y
+);
+	assign y = a + b - c + d;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-none t:$macc t:$macc_v2 %u
+select -assert-min 1 t:$fa
+select -assert-count 1 t:$add
+design -reset
+
+read_verilog <<EOT
+module macc_const(
+	input [7:0] a, b, c,
+	output [7:0] y
+);
+	assign y = a + b + c + 8'd42;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-none t:$macc t:$macc_v2 %u
+select -assert-min 1 t:$fa
+select -assert-count 1 t:$add
+design -reset
+
+read_verilog <<EOT
+module macc_two(
+	input [7:0] a, b, c, d, e, f, g, h,
+	output [7:0] y1, y2
+);
+	assign y1 = a + b + c + d;
+	assign y2 = e + f + g + h;
+endmodule
+EOT
+hierarchy -auto-top
+proc
+alumacc
+opt
+csa_tree
+opt_clean
+select -assert-none t:$macc t:$macc_v2 %u
+select -assert-count 4 t:$fa
+select -assert-count 2 t:$add
+design -reset
diff --git a/tests/csa_tree/csa_tree_synth.ys b/tests/csa_tree/csa_tree_synth.ys
index 2ed1fe32c..c3be44f17 100644
--- a/tests/csa_tree/csa_tree_synth.ys
+++ b/tests/csa_tree/csa_tree_synth.ys
@@ -1,5 +1,3 @@
-# Assert against abc synth with and without csa, hopefully prevent regressions
-# Baseline
 read_verilog <<EOT
 module bench(
 	input [7:0] a, b, c, d, e, f, g, h,
@@ -16,7 +14,6 @@ abc -g AND,OR,XOR
 select -assert-min 236 t:$_AND_ t:$_OR_ t:$_XOR_ %u
 design -reset
 
-# With csa_tree
 read_verilog <<EOT
 module bench(
 	input [7:0] a, b, c, d, e, f, g, h,
@@ -34,7 +31,6 @@ abc -g AND,OR,XOR
 select -assert-max 235 t:$_AND_ t:$_OR_ t:$_XOR_ %u
 design -reset
 
-# Depth-otimal baseline
 read_verilog <<EOT
 module bench(
 	input [7:0] a, b, c, d, e, f, g, h,
@@ -51,7 +47,6 @@ abc -D 1
 select -assert-min 240 t:$_AND_ t:$_NAND_ t:$_OR_ t:$_NOR_ t:$_XOR_ t:$_XNOR_ t:$_NOT_ %u
 design -reset
 
-# Depth-optimal with csa_tree
 read_verilog <<EOT
 module bench(
 	input [7:0] a, b, c, d, e, f, g, h,
diff --git a/tests/csa_tree/run-test.sh b/tests/csa_tree/run-test.sh
index 0ef575c48..2e3f5235c 100755
--- a/tests/csa_tree/run-test.sh
+++ b/tests/csa_tree/run-test.sh
@@ -2,6 +2,6 @@
 source ../common-env.sh
 set -e
 for x in *.ys; do
-	echo "Running $x.."
-	../../yosys -ql ${x%.ys}.log $x
+  echo "Running $x.."
+  ../../yosys -ql ${x%.ys}.log $x
 done