m68k/fpsp040/slog2.S

5 |	logarithm of an input argument X.
13 |       OUTPUT: log_10(X) or log_2(X) returned in floating-point
32 |       Step 0.   If X < 0, create a NaN and raise the invalid operation
37 |       Step 1.   Call slognd to obtain Y = log(X), the natural log of X.
38 |       Notes:    Even if X is denormalized, log(X) is always normalized.
40 |       Step 2.   Compute log_10(X) = log(X) * (1/log(10)).
47 |       Step 0.   If X < 0, create a NaN and raise the invalid operation
52 |       Step 1.   Call sLogN to obtain Y = log(X), the natural log of X.
54 |       Step 2.   Compute log_10(X) = log(X) * (1/log(10)).
61 |       Step 0.   If X < 0, create a NaN and raise the invalid operation
66 |       Step 1.   Call slognd to obtain Y = log(X), the natural log of X.
67 |       Notes:    Even if X is denormalized, log(X) is always normalized.
69 |       Step 2.   Compute log_10(X) = log(X) * (1/log(2)).
76 |       Step 0.   If X < 0, create a NaN and raise the invalid operation
81 |       Step 1.   If X is not an integer power of two, i.e., X != 2^k,
85 |            2.1  Get integer k, X = 2^k.
89 |       Step 3.   Call sLogN to obtain Y = log(X), the natural log of X.
91 |       Step 4.   Compute log_2(X) = log(X) * (1/log(2)).
117 |--entry point for Log10(X), X is denormalized
122 	bsr		slognd			| ...log(X), X denorm.
129 |--entry point for Log10(X), X is normalized
135 	bsr		slogn			| ...log(X), X normal.
143 |--entry point for Log2(X), X is denormalized
149 	bsr		slognd			| ...log(X), X denorm.
156 |--entry point for Log2(X), X is normalized
161 	bnes		continue		| ...X is not 2^k
168 |--X = 2^k.
179 	bsr		slogn			| ...log(X), X normal.