* h8300/compile.c (decode): Initialize op3.type to -1.
	(step_once): Adjust test of op3.type.

diff --git a/sim/h8300/compile.c b/sim/h8300/compile.c
index c1c61d8211..af9137d6d6 100644
--- a/sim/h8300/compile.c
+++ b/sim/h8300/compile.c
@@ -568,6 +568,7 @@ decode (SIM_DESC sd, int addr, unsigned char *data, decoded_inst *dst)
 
   dst->dst.type = -1;
   dst->src.type = -1;
+  dst->op3.type = -1;
 
   /* Find the exact opcode/arg combo.  */
   for (q = h8_opcodes; q->name; q++)
@@ -1940,7 +1941,7 @@ step_once (SIM_DESC sd, SIM_CPU *cpu)
 		of the same register.
 	  */
 
-	  if (code->op3.type == 0)
+	  if (code->op3.type == -1)
 	    {
 	      /* Short form: src == INDEXB/INDEXW, dst == op3 == 0.
 		 We get to compose dst and op3 as follows: