Fixed:
* SetString calls in bitwise tests
* Aliasing problem with self bitwise test
* One test case that was just flat out wrong
* Slice panics in nat.or and nat.xor
* Aliasing problems in Int.And, Int.AndNot, Int.Or, Int.Xor
Fixes#1007.
R=gri
CC=golang-dev
https://golang.org/cl/1895049
- sign to determine if a value is < 0, == 0, > 0
- abs to compute absolute value
- Rat.IsInt to test if a rational number is representable as an integer
R=rsc
CC=golang-dev
https://golang.org/cl/1761042
* Allow an exponent part. This is necessary for exp/eval.
* Fix a bug for input that had no numbers after the decimal.
* In Int.SetString, allow a leading + sign.
* In Int.SetString, error if the input is "-" with no number.
* In nat.scan, normalize the resulting nat.
R=gri
CC=golang-dev
https://golang.org/cl/1733045
ModInverse is just a small wrapper around GcdInt, but it's nice to
have in order to be clear about what one is doing in other code.
R=gri, agl1
CC=golang-dev
https://golang.org/cl/1244045
- implemented setWord, use it where setUint64 is wrong
- divLarge: use fast mulWW, divWW; implemented mulWW, divWW
- better assembly code for addMulVVW
R=rsc
CC=golang-dev
https://golang.org/cl/1258042
- support for binary prefix 0b (to match fmt.Format)
- renamed nat.new -> nat.setUint64 for consistency
- more tests
R=r
CC=golang-dev
https://golang.org/cl/1233041
- removed last argument (n) from all core arithmetic routines;
instead, use the length of the result
- simplified nat.make implementation and chose a better capacity
for new values, removed a TODO in the process
Changing the constant e from 1 (old) to 4 (new) improved
pidigits -s -n 10000 by ~9% (on a 3.06GHz Intel Core 2 Duo):
user 0m3.882s (old)
user 0m3.549s (new)
R=rsc
CC=golang-dev
https://golang.org/cl/1133043
- no need to make copies in cases of aliases
- removed deprecated internal shift functions
- minor unrelated simplifications
This change improves pidigits -s -n10000 by almost 20%:
user 0m6.156s (old)
user 0m4.999s (new)
(pidigits -s -n20000 goes from ~25s to ~19s)
R=rsc
CC=golang-dev
https://golang.org/cl/1149041
- 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
- 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
There was a bug in makeN that caused lots of unnecessary
allocations. Fixing this exposed a few bugs in other
functions which worked when makeN allocated a new slice, but
failed when it simply resized an existing slice. The result
is a pretty big performance improvement. When running
pidigits, here were the numbers I got on amd64:
Before this change:
pidigits 10000
gcc -O2 pidigits.c -lgmp 2.09u 0.02s 2.11r
gc pidigits 12.68u 0.04s 12.72r
gc_B pidigits 12.71u 0.03s 12.75r
After:
pidigits 10000
gcc -O2 pidigits.c -lgmp 2.09u 0.00s 2.10r
gc pidigits 6.82u 0.00s 6.85r
gc_B pidigits 6.55u 0.01s 6.59r
R=rsc, gri
CC=golang-dev
https://golang.org/cl/953042
probablyPrime would return false negatives in some cases.
This code has now been tested against GMP for several million iterations without issues.
Fixes#638.
R=rsc
CC=golang-dev
https://golang.org/cl/252041
parsing and printing to new syntax.
Use -oldparser to parse the old syntax,
use -oldprinter to print the old syntax.
2) Change default gofmt formatting settings
to use tabs for indentation only and to use
spaces for alignment. This will make the code
alignment insensitive to an editor's tabwidth.
Use -spaces=false to use tabs for alignment.
3) Manually changed src/exp/parser/parser_test.go
so that it doesn't try to parse the parser's
source files using the old syntax (they have
new syntax now).
4) gofmt -w src misc test/bench
1st set of files.
R=rsc
CC=agl, golang-dev, iant, ken2, r
https://golang.org/cl/180047
