Fix bug in handling of registers with option type

Also add test cases and Isabelle lemmas

2 files changed, 23 insertions, 0 deletions

diff --git a/test/typecheck/pass/reg_list.sail b/test/typecheck/pass/reg_list.sail
new file mode 100644
index 00000000..bf776942
--- /dev/null
+++ b/test/typecheck/pass/reg_list.sail
@@ -0,0 +1,7 @@
+register X : list(bool)
+
+val init_X : unit -> unit effect {wreg}
+function init_X () = {
+  X = [||];
+}
+
diff --git a/test/typecheck/pass/reg_option.sail b/test/typecheck/pass/reg_option.sail
new file mode 100644
index 00000000..55317d1f
--- /dev/null
+++ b/test/typecheck/pass/reg_option.sail
@@ -0,0 +1,16 @@
+$include <arith.sail>
+$include <flow.sail>
+$include <option.sail>
+
+register X : option(int)
+
+val inc_X : unit -> int effect {rreg, wreg}
+function inc_X () = {
+  let x : int = match X {
+    Some(x) => x + 1,
+    None() => 0
+  };
+  X = Some(x);
+  return x;
+}
+