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dpgeorgedpgeorge
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py: Try to autodetect machine endianness when not defined by port.
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Lines changed: 20 additions & 7 deletions

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‎py/mpconfig.h‎

Lines changed: 20 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -434,13 +434,26 @@ typedef double mp_float_t;
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// mp_int_t value with most significant bit set
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#define WORD_MSBIT_HIGH (((mp_uint_t)1) << (BYTES_PER_WORD * 8 - 1))
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#if !defined(MP_ENDIANNESS_LITTLE) && !defined(MP_ENDIANNESS_BIG)
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// Just because most archs are such?
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#define MP_ENDIANNESS_LITTLE (1)
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#endif
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// Ensure we don't accidentally set both endiannesses
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#if MP_ENDIANNESS_BIG
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#define MP_ENDIANNESS_LITTLE (0)
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// Make sure both MP_ENDIANNESS_LITTLE and MP_ENDIANNESS_BIG are
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// defined and that they are the opposite of each other.
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#if defined(MP_ENDIANNESS_LITTLE)
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#define MP_ENDIANNESS_BIG (!MP_ENDIANNESS_LITTLE)
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#elif defined(MP_ENDIANNESS_BIG)
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#define MP_ENDIANNESS_LITTLE (!MP_ENDIANNESS_BIG)
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#else
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// Endiannes not defined by port so try to autodetect it.
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#if defined(__BYTE_ORDER__)
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#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
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#define MP_ENDIANNESS_LITTLE (1)
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#else
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#define MP_ENDIANNESS_LITTLE (0)
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#endif
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#elif defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || defined (_BIG_ENDIAN)
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#define MP_ENDIANNESS_LITTLE (0)
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#else
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#error endianness not defined and cannot detect it
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#endif
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#define MP_ENDIANNESS_BIG (!MP_ENDIANNESS_LITTLE)
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#endif
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// Make a pointer to RAM callable (eg set lower bit for Thumb code)

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