Displacement of the python2.7.13 opcode encountered some pits

There are two main pits

1.XXXSLICE related opcode

#define SLICE      #define slice_1    #define slice_2    #define slice_3    #define Store_slice#define store_slice_1  #define store_slice_2  #define store_ Slice_3  #define delete_slice   #define#define#define Delete_ Slice_3  

Because these macro definitions are continuous at compile and run time, the Python source code is operated in Slice+1,opcode-slice & 1.

If the permutation is discontinuous, there will be a problem.

2.call_functionxxx related opcode

/* The next 3 opcodes must be contiguous and satisfy   (call_function_var-call_function) & 3 = = 1  */#define CA Ll_function_var            /* #args + (#kwargs <<8) */#define CALL_FUNCTION_KW/           * #args + (#kwargs <<8) */# Define CALL_FUNCTION_VAR_KW        /* #args + (#kwargs <<8) */

Similar to the 1 issue, CEVAL.C (opcode-call_function) & 3, so it must also be guaranteed (call_function_var-call_function) & 3 = = 1, and these three macros are continuously

Other reference https://zhuanlan.zhihu.com/p/25850970 can be

Displacement of the python2.7.13 opcode encountered some pits