diff --git a/tools/virtualmips/mips-dis.c b/tools/virtualmips/mips-dis.c
index 27506d6..1431a7a 100644
--- a/tools/virtualmips/mips-dis.c
+++ b/tools/virtualmips/mips-dis.c
@@ -162,12 +162,6 @@ print_address (unsigned address, FILE *stream)
         fprintf (stream, "0x%x", address);
 }
 
-static void
-memory_error (int status, unsigned memaddr, FILE *stream)
-{
-    fprintf (stream, "Error reading memory at 0x%08x: %s", memaddr, strerror (status));
-}
-
 static const struct mips_cp0sel_name *
 lookup_mips_cp0sel_name (const struct
     mips_cp0sel_name *names, unsigned int len, unsigned int cp0reg,
@@ -777,42 +771,6 @@ print_insn_mips (unsigned memaddr,
     fprintf (stream, "0x%lx", word);
 }
 
-static unsigned
-getb16 (const unsigned char *buf)
-{
-    return (buf[0] << 8) | buf[1];
-}
-
-static unsigned
-getl16 (const unsigned char *buf)
-{
-    return (buf[1] << 8) | buf[0];
-}
-
-static unsigned
-getb32 (const unsigned char *buf)
-{
-    unsigned long v;
-
-    v = (unsigned long) buf[0] << 24;
-    v |= (unsigned long) buf[1] << 16;
-    v |= (unsigned long) buf[2] << 8;
-    v |= (unsigned long) buf[3];
-    return v;
-}
-
-static unsigned
-getl32 (const unsigned char *buf)
-{
-    unsigned long v;
-
-    v = (unsigned long) buf[0];
-    v |= (unsigned long) buf[1] << 8;
-    v |= (unsigned long) buf[2] << 16;
-    v |= (unsigned long) buf[3] << 24;
-    return v;
-}
-
 /*
  * Disassemble an operand for a mips16 instruction.
  */
@@ -1239,14 +1197,13 @@ print_mips16_insn_arg (char type,
 static void print_insn_mips16 (unsigned memaddr,
     unsigned int opcode, int nbytes, FILE *stream)
 {
-    int status;
-    unsigned char buffer[2];
     int insn, use_extend, extend;
     const struct mips_opcode *op, *opend;
 
     insn = opcode;
     if (nbytes == 2) {
         use_extend = 0;
+        extend = 0;
         insn = opcode;
     } else {
         if ((opcode & 0xf8000000) == 0xf0000000) {
diff --git a/tools/virtualmips/mips_codetable.c b/tools/virtualmips/mips_codetable.c
index aaf38d2..8539655 100644
--- a/tools/virtualmips/mips_codetable.c
+++ b/tools/virtualmips/mips_codetable.c
@@ -1454,6 +1454,32 @@ static int teqi_op (cpu_mips_t * cpu, mips_insn_t insn)
     return (0);
 }
 
+/*
+ * DI and EI instructions
+ */
+static int mfmc0_op (cpu_mips_t * cpu, mips_insn_t insn)
+{
+    int rt = bits (insn, 16, 20);
+    int rd = bits (insn, 11, 15);
+    int func = bits (insn, 0, 10);
+
+    if (rd == 12) {
+        switch (func) {
+        case 0x020:
+            /* ei - enable interrupts */
+            cpu->reg_set (cpu, rt, cpu->cp0.reg [MIPS_CP0_STATUS]);
+            cpu->cp0.reg [MIPS_CP0_STATUS] |= MIPS_CP0_STATUS_IE;
+            return 0;
+        case 0x000:
+            /* di - disable interrupts */
+            cpu->reg_set (cpu, rt, cpu->cp0.reg [MIPS_CP0_STATUS]);
+            cpu->cp0.reg [MIPS_CP0_STATUS] &= ~MIPS_CP0_STATUS_IE;
+            return 0;
+        }
+    }
+    return unknown_op (cpu, insn);
+}
+
 static int tlb_op (cpu_mips_t * cpu, mips_insn_t insn)
 {
     uint16_t func = bits (insn, 0, 5);
@@ -1902,7 +1928,7 @@ static const struct mips_op_desc mips_cop0_opcodes[] = {
     {"?cop0",   undef_cop0,	0x8},
     {"?cop0",   undef_cop0,	0x9},
     {"?cop0",   rdpgpr_op,	0xa},
-    {"?cop0",   undef_cop0,	0xb},
+    {"?cop0",   mfmc0_op,   0xb},
     {"?cop0",   undef_cop0,	0xc},
     {"?cop0",   undef_cop0,	0xd},
     {"wrpgpr",  wrpgpr_op,	0xe},