1/* This file contains code shared by the compiler and the peephole 2 optimizer. 3 */ 4 5#ifdef WORDS_BIGENDIAN 6# define PACKOPARG(opcode, oparg) ((_Py_CODEUNIT)(((opcode) << 8) | (oparg))) 7#else 8# define PACKOPARG(opcode, oparg) ((_Py_CODEUNIT)(((oparg) << 8) | (opcode))) 9#endif 10 11/* Minimum number of code units necessary to encode instruction with 12 EXTENDED_ARGs */ 13static int 14instrsize(unsigned int oparg) 15{ 16 return oparg <= 0xff ? 1 : 17 oparg <= 0xffff ? 2 : 18 oparg <= 0xffffff ? 3 : 19 4; 20} 21 22/* Spits out op/oparg pair using ilen bytes. codestr should be pointed at the 23 desired location of the first EXTENDED_ARG */ 24static void 25write_op_arg(_Py_CODEUNIT *codestr, unsigned char opcode, 26 unsigned int oparg, int ilen) 27{ 28 switch (ilen) { 29 case 4: 30 *codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 24) & 0xff); 31 case 3: 32 *codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 16) & 0xff); 33 case 2: 34 *codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 8) & 0xff); 35 case 1: 36 *codestr++ = PACKOPARG(opcode, oparg & 0xff); 37 break; 38 default: 39 assert(0); 40 } 41} 42