diff --git a/Python/ceval.c b/Python/ceval.c
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -892,7 +892,7 @@
     TARGET_##op: \
         opcode = op; \
         if (HAS_ARG(op)) \
-            oparg = NEXTARG(); \
+            {oparg = GETARG(); EATARG();} \
     case op: \
         goto impl; \
 
@@ -900,7 +900,7 @@
     TARGET_##op: \
         opcode = op; \
         if (HAS_ARG(op)) \
-            oparg = NEXTARG(); \
+            {oparg = GETARG(); EATARG();} \
     case op:
 
 
@@ -996,8 +996,14 @@
 
 #define INSTR_OFFSET()  ((int)(next_instr - first_instr))
 #define NEXTOP()        (*next_instr++)
-#define NEXTARG()       (next_instr += 2, (next_instr[-1]<<8) + next_instr[-2])
+#define EATARG()        (next_instr += 2)
+#if PY_LITTLE_ENDIAN
+#define GETARG()        ((int)(*((unsigned short *)next_instr)))
+#define PEEKARG()       ((int)(*((unsigned short *)(next_instr + 1))))
+#else
+#define GETARG()        (next_instr[1]<<8) + next_instr[0])
 #define PEEKARG()       ((next_instr[2]<<8) + next_instr[1])
+#endif
 #define JUMPTO(x)       (next_instr = first_instr + (x))
 #define JUMPBY(x)       (next_instr += (x))
 
@@ -1326,7 +1332,7 @@
         oparg = 0;   /* allows oparg to be stored in a register because
             it doesn't have to be remembered across a full loop */
         if (HAS_ARG(opcode))
-            oparg = NEXTARG();
+            {oparg = GETARG(); EATARG();};
     dispatch_opcode:
 #ifdef DYNAMIC_EXECUTION_PROFILE
 #ifdef DXPAIRS
@@ -3433,7 +3439,8 @@
 
         TARGET(EXTENDED_ARG) {
             opcode = NEXTOP();
-            oparg = oparg<<16 | NEXTARG();
+            oparg = oparg<<16 | GETARG();
+            EATARG();
             goto dispatch_opcode;
         }