The original implementation used 16 int "words" but only 29 bits per word
for a total of 16*29 = 464 bits, with a space consumption of 16*64 = 1024
bits on a 64 bit machine. Switching to 512 bits increases precision while
still using (in the worst case) half the amount of memory per mp value on
a 64 bit machine.
Also: Decreased permitted number of least-significant mantissa bits which
may be incorrect when considering if a precise floating-point constant is
an integer from 29 to 16 bits.
Change-Id: Iee9287056f0e9aa4f06ceac0724ff4674f710c53
Reviewed-on: https://go-review.googlesource.com/8429
Reviewed-by: Russ Cox <rsc@golang.org>
All multi-precision arithmetic is now based on math/big.
- passes all.bash
- added test cases for fixed bugs
Fixes#7740.
Fixes#6866.
Change-Id: I67268b91766970ced3b928260053ccdce8753d58
Reviewed-on: https://go-review.googlesource.com/7912
Reviewed-by: Russ Cox <rsc@golang.org>
