47 lines
570 B
C
47 lines
570 B
C
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/*
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* $Source$
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* $State$
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* $Revision$
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*/
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/* no headers allowed! */
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/* Given a double, calculates the mantissa and exponent.
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*
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* This function is intended to be called internally by the code generator,
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* so the calling convention is odd.
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*/
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int __fef8(double* fp)
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{
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double f = *fp;
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int exponent, sign;
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if (f == 0.0)
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return 0;
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if (f < 0.0)
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{
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sign = -1;
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f = -f;
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}
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else
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sign = 0;
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exponent = 0;
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while (f >= 1.0)
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{
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f /= 2.0;
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exponent++;
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}
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while (f < 0.5)
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{
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f *= 2.0;
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exponent--;
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}
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*fp = (sign) ? -f : f;
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return exponent;
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}
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