1 files changed, 54 insertions, 0 deletions
diff --git a/tests/simple/dff_init.v b/tests/simple/dff_init.v
new file mode 100644
index 000000000..375ea5c4d
--- /dev/null
+++ b/tests/simple/dff_init.v
@@ -0,0 +1,54 @@
+module dff0_test(n1, n1_inv, clk);
+  input clk;
+  output n1;
+  reg n1 = 32'd0;
+  output n1_inv;
+  always @(posedge clk)
+      n1 <= n1_inv;
+  assign n1_inv = ~n1;
+endmodule
+
+module dff1_test(n1, n1_inv, clk);
+  input clk;
+  (* init = 32'd1 *)
+  output n1;
+  reg n1 = 32'd1;
+  output n1_inv;
+  always @(posedge clk)
+      n1 <= n1_inv;
+  assign n1_inv = ~n1;
+endmodule
+
+module dff0a_test(n1, n1_inv, clk);
+  input clk;
+  (* init = 32'd0 *) // Must be consistent with reg initialiser below
+  output n1;
+  reg n1 = 32'd0;
+  output n1_inv;
+  always @(posedge clk)
+      n1 <= n1_inv;
+  assign n1_inv = ~n1;
+endmodule
+
+module dff1a_test(n1, n1_inv, clk);
+  input clk;
+  (* init = 32'd1 *) // Must be consistent with reg initialiser below
+  output n1;
+  reg n1 = 32'd1;
+  output n1_inv;
+  always @(posedge clk)
+      n1 <= n1_inv;
+  assign n1_inv = ~n1;
+endmodule
+
+module dff_test_997 (y, clk, wire4);
+// https://github.com/YosysHQ/yosys/issues/997
+   output wire [1:0] y;
+   input             clk;
+   input signed      wire4;
+   reg [1:0]  reg10 = 0;
+   always @(posedge clk) begin
+      reg10 <= wire4;
+   end
+   assign y = reg10;
+endmodule