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20 lines
389 B
C
20 lines
389 B
C
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#include <limits.h>
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#include "ruby.h"
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int
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signbit(double x)
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{
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enum {double_per_long = sizeof(double) / sizeof(long)};
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enum {long_msb = sizeof(long) * CHAR_BIT - 1};
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union {double d; unsigned long i[double_per_long];} u;
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unsigned long l;
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u.d = x;
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#ifdef WORDS_BIGENDIAN
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l = u.i[0];
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#else
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l = u.i[double_per_long - 1];
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#endif
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return (int)(l >> long_msb);
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}
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