1 files changed, 4 insertions, 1 deletions

diff --git a/lopcodes.h b/lopcodes.h
index fd578c68..c5e9cf81 100644
--- a/lopcodes.h
+++ b/lopcodes.h
@@ -359,6 +359,7 @@ OP_EXTRAARG/*	Ax	extra (larger) argument for previous opcode	*/
 ** bit 4: operator is a test (next instruction must be a jump)
 ** bit 5: instruction uses 'L->top' set by previous instruction (when B == 0)
 ** bit 6: instruction sets 'L->top' for next instruction (when C == 0)
+** bit 7: instruction is an MM instruction (call a metamethod)
 */
 
 LUAI_DDEC(const lu_byte luaP_opmodes[NUM_OPCODES];)
@@ -368,6 +369,7 @@ LUAI_DDEC(const lu_byte luaP_opmodes[NUM_OPCODES];)
 #define testTMode(m)    (luaP_opmodes[m] & (1 << 4))
 #define testITMode(m)   (luaP_opmodes[m] & (1 << 5))
 #define testOTMode(m)   (luaP_opmodes[m] & (1 << 6))
+#define testMMMode(m)   (luaP_opmodes[m] & (1 << 7))
 
 /* "out top" (set top for next instruction) */
 #define isOT(i)  \
@@ -377,7 +379,8 @@ LUAI_DDEC(const lu_byte luaP_opmodes[NUM_OPCODES];)
 /* "in top" (uses top from previous instruction) */
 #define isIT(i)         (testITMode(GET_OPCODE(i)) && GETARG_B(i) == 0)
 
-#define opmode(ot,it,t,a,m) (((ot)<<6) | ((it)<<5) | ((t)<<4) | ((a)<<3) | (m))
+#define opmode(mm,ot,it,t,a,m)  \
+    (((mm) << 7) | ((ot) << 6) | ((it) << 5) | ((t) << 4) | ((a) << 3) | (m))
 
 
 /* number of list items to accumulate before a SETLIST instruction */