1 files changed, 8 insertions, 0 deletions
diff --git a/techlibs/gowin/arith_map.v b/techlibs/gowin/arith_map.v
index b6f9e8c38..42aaba870 100644
--- a/techlibs/gowin/arith_map.v
+++ b/techlibs/gowin/arith_map.v
@@ -26,21 +26,29 @@ module _80_gw1n_alu(A, B, CI, BI, X, Y, CO);
    parameter B_WIDTH = 1;
    parameter Y_WIDTH = 1;
 
+   (* force_downto *)
    input [A_WIDTH-1:0] A;
+   (* force_downto *)
    input [B_WIDTH-1:0] B;
+   (* force_downto *)
    output [Y_WIDTH-1:0] X, Y;
 
    input 		CI, BI;
+   (* force_downto *)
    output [Y_WIDTH-1:0] CO;
 
    wire 		_TECHMAP_FAIL_ = Y_WIDTH <= 2;
 
+   (* force_downto *)
    wire [Y_WIDTH-1:0] 	A_buf, B_buf;
    \$pos #(.A_SIGNED(A_SIGNED), .A_WIDTH(A_WIDTH), .Y_WIDTH(Y_WIDTH)) A_conv (.A(A), .Y(A_buf));
    \$pos #(.A_SIGNED(B_SIGNED), .A_WIDTH(B_WIDTH), .Y_WIDTH(Y_WIDTH)) B_conv (.A(B), .Y(B_buf));
 
+   (* force_downto *)
    wire [Y_WIDTH-1:0] 	AA = A_buf;
+   (* force_downto *)
    wire [Y_WIDTH-1:0] 	BB = B_buf;
+   (* force_downto *)
    wire [Y_WIDTH-1:0] 	C = {CO, CI};
 
    genvar 		i;