diff options
Diffstat (limited to 'Python/wordcode_helpers.h')
| -rw-r--r-- | Python/wordcode_helpers.h | 41 | 
1 files changed, 41 insertions, 0 deletions
| diff --git a/Python/wordcode_helpers.h b/Python/wordcode_helpers.h new file mode 100644 index 0000000..b0e3a91 --- /dev/null +++ b/Python/wordcode_helpers.h @@ -0,0 +1,41 @@ +/* This file contains code shared by the compiler and the peephole +   optimizer. + */ + +#ifdef WORDS_BIGENDIAN +#  define PACKOPARG(opcode, oparg) ((_Py_CODEUNIT)(((opcode) << 8) | (oparg))) +#else +#  define PACKOPARG(opcode, oparg) ((_Py_CODEUNIT)(((oparg) << 8) | (opcode))) +#endif + +/* Minimum number of code units necessary to encode instruction with +   EXTENDED_ARGs */ +static int +instrsize(unsigned int oparg) +{ +    return oparg <= 0xff ? 1 : +        oparg <= 0xffff ? 2 : +        oparg <= 0xffffff ? 3 : +        4; +} + +/* Spits out op/oparg pair using ilen bytes. codestr should be pointed at the +   desired location of the first EXTENDED_ARG */ +static void +write_op_arg(_Py_CODEUNIT *codestr, unsigned char opcode, +    unsigned int oparg, int ilen) +{ +    switch (ilen) { +        case 4: +            *codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 24) & 0xff); +        case 3: +            *codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 16) & 0xff); +        case 2: +            *codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 8) & 0xff); +        case 1: +            *codestr++ = PACKOPARG(opcode, oparg & 0xff); +            break; +        default: +            assert(0); +    } +} | 
