Add hardware-accurate QEXP and QLOG #490
Merged
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Current QLOG and QEXP constant evaluation is based on libm floating-point functions, so may cause inconsistency between host systems. I think there was a problem with
QLOG 0
, but other values are usually only off by a few LSBs, which speaks to the quality of both the glibc math library and the P2 hardware. The implementation is derived from PNut source, though that isn't accurate either (rounding bug in QEXP).Bonus: add a missing header definition for
log2
.