diff --git a/cpu/ppc/ppcdisasm.cpp b/cpu/ppc/ppcdisasm.cpp
index e5e0e17..e7ea020 100644
--- a/cpu/ppc/ppcdisasm.cpp
+++ b/cpu/ppc/ppcdisasm.cpp
@@ -1025,14 +1025,14 @@ void opc_group31(PPCDisasmContext* ctx)
         /* dcba, dcbf, dcbi, dcbst, dcbt, dcbz, icbi */
         else if ((index == 1) | (index == 2) | (index == 7) \
             | (index == 8) | (index == 14) | (index == 23) \
-             | (index == 30) | (index == 31)) {
+            | (index == 30) | (index == 31)) {
             if (rc_set | (rs != 0)) {
                 opc_illegal(ctx);
                 return;
             }
             else {
                 if (ra == 0)
-                    ctx->instr_str = my_sprintf("%-8sr%d, 0, r%d", opcode, rb);
+                    ctx->instr_str = my_sprintf("%-8s0, r%d", opcode, rb);
                 else
                     fmt_twoop(ctx->instr_str, opcode, ra, rb);
                 return;
@@ -1040,6 +1040,7 @@ void opc_group31(PPCDisasmContext* ctx)
         }
         else if (index == 17) { /* tlbsync */
             ctx->instr_str = my_sprintf("%-8s", opcode);
+            return;
         }
         else {
             opc_illegal(ctx);
diff --git a/cpu/ppc/test/ppcdisasmtest.csv b/cpu/ppc/test/ppcdisasmtest.csv
index 5633bbd..208ce13 100644
--- a/cpu/ppc/test/ppcdisasmtest.csv
+++ b/cpu/ppc/test/ppcdisasmtest.csv
@@ -366,7 +366,7 @@
 # misc instructions
 0xFFF00100,0x7D290034,cntlzw,r9,r9
 0xFFF00100,0x7FFF0035,cntlzw.,r31,r31
-0xFFF00100,0x7C00D7AC,icbi,r0,r26
+0xFFF00100,0x7C00D7AC,icbi,0,r26
 0xFFF00100,0x7D604828,lwarx,r11,0,r9
 0xFFF00100,0x7CBC04AA,lswi,r5,r28,0x20
 0xFFF00100,0x7FEF2C2A,lswx,r31,r15,r5