diff --git a/techlibs/common/Makefile.inc b/techlibs/common/Makefile.inc
index 6b377855e..fa5c2a825 100644
--- a/techlibs/common/Makefile.inc
+++ b/techlibs/common/Makefile.inc
@@ -35,3 +35,4 @@ $(eval $(call add_share_file,share,techlibs/common/abc9_map.v))
 $(eval $(call add_share_file,share,techlibs/common/abc9_unmap.v))
 $(eval $(call add_share_file,share,techlibs/common/cmp2lcu.v))
 $(eval $(call add_share_file,share,techlibs/common/cmp2softlogic.v))
+$(eval $(call add_share_file,share/choices,techlibs/common/choices/kogge-stone.v))
diff --git a/techlibs/common/choices/kogge-stone.v b/techlibs/common/choices/kogge-stone.v
new file mode 100644
index 000000000..eb97a75d8
--- /dev/null
+++ b/techlibs/common/choices/kogge-stone.v
@@ -0,0 +1,53 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2024  Martin Povišer <povik@cutebit.org>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+(* techmap_celltype = "$lcu" *)
+module _80_lcu_kogge_stone (P, G, CI, CO);
+	parameter WIDTH = 2;
+
+	(* force_downto *)
+	input [WIDTH-1:0] P, G;
+	input CI;
+
+	(* force_downto *)
+	output [WIDTH-1:0] CO;
+
+	integer i, j;
+	(* force_downto *)
+	reg [WIDTH-1:0] p, g;
+
+	wire [1023:0] _TECHMAP_DO_ = "proc; opt -fast";
+
+	always @* begin
+		p = P;
+		g = G;
+
+		// in almost all cases CI will be constant zero
+		g[0] = g[0] | (p[0] & CI);
+
+		for (i = 0; i < $clog2(WIDTH); i = i + 1) begin
+			for (j = 2**i; j < WIDTH; j = j + 1) begin
+				g[j] = g[j] | p[j] & g[j - 2**i];
+				p[j] = p[j] & p[j - 2**i];
+			end
+		end
+	end
+
+	assign CO = g;
+endmodule
diff --git a/techlibs/common/techmap.v b/techlibs/common/techmap.v
index 38ca33cb9..68b276588 100644
--- a/techlibs/common/techmap.v
+++ b/techlibs/common/techmap.v
@@ -207,7 +207,7 @@ module _90_fa (A, B, C, X, Y);
 endmodule
 
 (* techmap_celltype = "$lcu" *)
-module _90_lcu (P, G, CI, CO);
+module _90_lcu_brent_kung (P, G, CI, CO);
 	parameter WIDTH = 2;
 
 	(* force_downto *)
@@ -230,7 +230,6 @@ module _90_lcu (P, G, CI, CO);
 		// in almost all cases CI will be constant zero
 		g[0] = g[0] | (p[0] & CI);
 
-`ifndef KOGGE_STONE
 		// [[CITE]] Brent Kung Adder
 		// R. P. Brent and H. T. Kung, "A Regular Layout for Parallel Adders",
 		// IEEE Transaction on Computers, Vol. C-31, No. 3, p. 260-264, March, 1982
@@ -250,14 +249,6 @@ module _90_lcu (P, G, CI, CO);
 				p[j] = p[j] & p[j - 2**(i-1)];
 			end
 		end
-`else
-		for (i = 0; i < $clog2(WIDTH); i = i + 1) begin
-			for (j = 2**i; j < WIDTH; j = j + 1) begin
-				g[j] = g[j] | p[j] & g[j - 2**i];
-				p[j] = p[j] & p[j - 2**i];
-			end
-		end
-`endif
 	end
 
 	assign CO = g;