testsuite/synth: add testcase for #951

1 files changed, 48 insertions, 0 deletions

diff --git a/testsuite/synth/issue951/tb_ent.vhdl b/testsuite/synth/issue951/tb_ent.vhdl
new file mode 100644
index 000000000..a6a752054
--- /dev/null
+++ b/testsuite/synth/issue951/tb_ent.vhdl
@@ -0,0 +1,48 @@
+entity tb_ent is
+end tb_ent;
+
+library ieee;
+use ieee.std_logic_1164.all;
+
+architecture behav of tb_ent is
+  signal clk : std_logic;
+  signal en : std_logic;
+  signal din : std_logic;
+  signal dout : std_logic;
+begin
+  dut: entity work.ent
+    port map (clk => clk, enable => en, i => din, o => dout);
+
+  process
+    procedure pulse is
+    begin
+      clk <= '0';
+      wait for 1 ns;
+      clk <= '1';
+      wait for 1 ns;
+    end pulse;
+  begin
+    din <= '0';
+    en <= '1';
+    pulse;
+    assert dout = '0' severity failure;
+
+    din <= '1';
+    en <= '1';
+    pulse;
+    assert dout = '1' severity failure;
+
+    din <= '0';
+    en <= '0';
+    pulse;
+    assert dout = '1' severity failure;
+    wait;
+
+    din <= '0';
+    en <= '1';
+    pulse;
+    assert dout = '0' severity failure;
+    wait;
+
+  end process;
+end behav;