Attempts to implement jalr, test not passing

bench/tests/op/jalr.s

@@ -0,0 +1,15 @@
+# expected: 000000BA, 0000018, 0000000A
+    .text
+_start:
+    jal x1, step1
+    add x31, x0, 0x00A
+    jal x0, finish
+step1:
+    jal x2, step2
+    add x31, x0, 0x0AB # This instruction should never be executed
+    add x31, x0, 0x0BA
+    jalr x31, 0(x1) # Check if return address is written to x31
+step2:
+    jalr x0, 1(x2) # return to step1, but 1 further
+finish:
+    nop