* Update the comments to agree with commit r226595.
* While here, fix a nearby typo in a comment.
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@ -19,20 +19,20 @@ __FBSDID("$FreeBSD$");
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* 1. Compute and return log2(x) in two pieces:
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* log2(x) = w1 + w2,
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* where w1 has 53-24 = 29 bit trailing zeros.
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* 2. Perform y*log2(x) = n+y' by simulating muti-precision
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* 2. Perform y*log2(x) = n+y' by simulating multi-precision
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* arithmetic, where |y'|<=0.5.
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* 3. Return x**y = 2**n*exp(y'*log2)
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*
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* Special cases:
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* 1. (anything) ** 0 is 1
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* 2. (anything) ** 1 is itself
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* 3. (anything) ** NAN is NAN
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* 3. (anything) ** NAN is NAN except 1 ** NAN = 1
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* 4. NAN ** (anything except 0) is NAN
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* 5. +-(|x| > 1) ** +INF is +INF
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* 6. +-(|x| > 1) ** -INF is +0
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* 7. +-(|x| < 1) ** +INF is +0
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* 8. +-(|x| < 1) ** -INF is +INF
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* 9. +-1 ** +-INF is NAN
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* 9. +-1 ** +-INF is 1
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* 10. +0 ** (+anything except 0, NAN) is +0
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* 11. -0 ** (+anything except 0, NAN, odd integer) is +0
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* 12. +0 ** (-anything except 0, NAN) is +INF
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@ -141,7 +141,7 @@ __ieee754_pow(double x, double y)
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if(ly==0) {
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if (iy==0x7ff00000) { /* y is +-inf */
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if(((ix-0x3ff00000)|lx)==0)
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return one; /* (-1)**+-inf is NaN */
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return one; /* (-1)**+-inf is 1 */
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else if (ix >= 0x3ff00000)/* (|x|>1)**+-inf = inf,0 */
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return (hy>=0)? y: zero;
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else /* (|x|<1)**-,+inf = inf,0 */
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