Because maps are mostly a hidden type, they must be
implemented using reflection values and will not be as
efficient as arrays and slices.
R=rsc
CC=golang-dev
https://golang.org/cl/1127041
- renamed Len -> BitLen, simplified implementation
- renamed old Div, Mod, DivMod -> Que, Rem, QuoRem
- implemented Div, Mod, DivMod (Euclidian definition, more
useful in a mathematical context)
- fixed a bug in Exp (-0 was possible)
- added extra tests to check normalized results everywhere
- uniformly set Int.neg flag at the end of computations
- minor cosmetic cleanups
- ran all tests
R=rsc
CC=golang-dev
https://golang.org/cl/1091041
Import _mulv from Inferno again, change R9 to R2.
Not sure what the other differences were for, but
they weren't working.
TBR=kaib
CC=golang-dev
https://golang.org/cl/1079041
When trying to regenerate src/pkg/runtime/darwin/386/defs.h
on a 64 bit capable Snow Leopard (OS X 10.6.3) system I
needed to add -f -m32 to godefs, as this OS and hardware
combination defaults to 64 bit compilation.
For safety, make the same change to the 32 bit FreeBSD
instructions in .../freebsd/defs.c. (Tested OK and no
problems introduced.)
R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/1052042
- fixed a couple of bugs in the process
(shift right was incorrect for negative numbers)
- added more tests and made some tests more robust
- changed pidigits back to using shifts to multiply
by 2 instead of add
This improves pidigit -s -n 10000 by approx. 5%:
user 0m6.496s (old)
user 0m6.156s (new)
R=rsc
CC=golang-dev
https://golang.org/cl/963044
This results in an improvement of > 35% for the existing Mul benchmark
using the same karatsuba threshold, and an improvement of > 50% with
a slightly higher threshold (32 instead of 30):
big.BenchmarkMul 500 6731846 ns/op (old alg.)
big.BenchmarkMul 500 4351122 ns/op (new alg.)
big.BenchmarkMul 500 3133782 ns/op (new alg., new theshold)
Also:
- tweaked calibrate.go, use same benchmark as for Mul benchmark
R=rsc
CC=golang-dev
https://golang.org/cl/1037041
Plus:
- calibration "test" - include in tests with gotest -calibrate
- basic Mul benchmark
- extra multiplication tests
- various cleanups
This change improves multiplication speed of numbers >= 30 words
in length (current threshold; found empirically with calibrate):
The multiplication benchmark (multiplication of a variety of long numbers)
improves by ~35%, individual multiplies can be significantly faster.
gotest -benchmarks=Mul
big.BenchmarkMul 500 6829290 ns/op (w/ Karatsuba)
big.BenchmarkMul 100 10600760 ns/op
There's no impact on pidigits for -n=10000 or -n=20000
because the operands are are too small.
R=rsc
CC=golang-dev
https://golang.org/cl/1004042
Rather than confuse people by linking to a spec we
don't fully support, let them just use the package docs.
R=r, rsc
CC=golang-dev
https://golang.org/cl/1016041