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https://github.com/python/cpython
synced 2024-11-02 14:48:31 +00:00
b2e5794870
* Add Py_UNREACHABLE() as an alias to abort(). * Use Py_UNREACHABLE() instead of assert(0) * Convert more unreachable code to use Py_UNREACHABLE() * Document Py_UNREACHABLE() and a few other macros.
44 lines
1.2 KiB
C
44 lines
1.2 KiB
C
/* This file contains code shared by the compiler and the peephole
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optimizer.
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*/
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#ifdef WORDS_BIGENDIAN
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# define PACKOPARG(opcode, oparg) ((_Py_CODEUNIT)(((opcode) << 8) | (oparg)))
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#else
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# define PACKOPARG(opcode, oparg) ((_Py_CODEUNIT)(((oparg) << 8) | (opcode)))
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#endif
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/* Minimum number of code units necessary to encode instruction with
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EXTENDED_ARGs */
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static int
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instrsize(unsigned int oparg)
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{
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return oparg <= 0xff ? 1 :
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oparg <= 0xffff ? 2 :
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oparg <= 0xffffff ? 3 :
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4;
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}
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/* Spits out op/oparg pair using ilen bytes. codestr should be pointed at the
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desired location of the first EXTENDED_ARG */
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static void
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write_op_arg(_Py_CODEUNIT *codestr, unsigned char opcode,
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unsigned int oparg, int ilen)
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{
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switch (ilen) {
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case 4:
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*codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 24) & 0xff);
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/* fall through */
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case 3:
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*codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 16) & 0xff);
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/* fall through */
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case 2:
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*codestr++ = PACKOPARG(EXTENDED_ARG, (oparg >> 8) & 0xff);
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/* fall through */
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case 1:
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*codestr++ = PACKOPARG(opcode, oparg & 0xff);
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break;
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default:
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Py_UNREACHABLE();
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}
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}
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