--- /dev/null
+.include "macros.inc"
+
+start
+
+test_name SEXTH_1
+mvi r1, 0
+sexth r3, r1
+check_r3 0
+
+test_name SEXTH_2
+load r1 0x7fff
+sexth r3, r1
+check_r3 0x00007fff
+
+test_name SEXTH_3
+load r1 0x8000
+sexth r3, r1
+check_r3 0xffff8000
+
+end