testsuite/synth: add a test for #1838

2 files changed, 48 insertions, 0 deletions

diff --git a/testsuite/synth/issue1838/regfile.vhdl b/testsuite/synth/issue1838/regfile.vhdl
new file mode 100644
index 000000000..4b1110d8c
--- /dev/null
+++ b/testsuite/synth/issue1838/regfile.vhdl
@@ -0,0 +1,38 @@
+library ieee;
+use ieee.std_logic_1164.all;
+use ieee.numeric_std.all;
+
+entity register_file is
+    port(
+        clk        : in std_logic;
+
+        write_en   : in std_ulogic;
+        write_addr : in std_ulogic_vector(6 downto 0);
+        write_data : in std_ulogic_vector(63 downto 0);
+
+        read_addr  : in std_ulogic_vector(6 downto 0);
+        read_data  : out std_ulogic_vector(63 downto 0)
+    );
+end entity register_file;
+
+architecture behaviour of register_file is
+    type regfile is array(0 to 127) of std_ulogic_vector(63 downto 0);
+    signal registers : regfile;
+begin
+    -- synchronous writes
+    register_write_0: process(clk)
+    begin
+        if rising_edge(clk) then
+            if write_en = '1' then
+                registers(to_integer(unsigned(write_addr))) <= write_data;
+            end if;
+        end if;
+    end process register_write_0;
+
+    -- asynchronous reads
+    register_read_0: process(all)
+    begin
+        read_data <= registers(to_integer(unsigned(read_addr)));
+    end process register_read_0;
+
+end architecture behaviour;
diff --git a/testsuite/synth/issue1838/testsuite.sh b/testsuite/synth/issue1838/testsuite.sh
new file mode 100755
index 000000000..2f5c80312
--- /dev/null
+++ b/testsuite/synth/issue1838/testsuite.sh
@@ -0,0 +1,10 @@
+#! /bin/sh
+
+. ../../testenv.sh
+
+GHDL_STD_FLAGS=--std=08
+synth_analyze regfile
+grep -q "variable registers :" syn_regfile.vhdl
+clean
+
+echo "Test successful"