Commit graph

3292 commits

Author SHA1 Message Date
nicoo
3d6fdffe14 factor::miller_rabin: Generalise tests to 32 and 64b Montgomery 2020-07-05 00:04:29 +02:00
nicoo
9b149a759b factor::miller_rabin: Hoist edge-cases (even, <2) out of test()
test() takes a modulus that is known to not be even or <2 (otherwise the
Montgomery value could not be constructed), so those checks can be hoisted
into is_prime() and out of the critical path.
2020-07-05 00:04:26 +02:00
nicoo
4f08e28167 factor::miller_rabin: Add property-based test 2020-07-05 00:04:08 +02:00
nicoo
d2fa0fe63c factor::miller_rabin::tests: small_composites → small_semiprimes
This is more descriptive, as semiprime are the products of 2 primes;
all semiprimes are composite, but not all composite numbers are semiprime.
2020-07-05 00:01:48 +02:00
nicoo
1e4d824829 factor::miller_rabin: Add negative test over all small composites 2020-07-05 00:01:44 +02:00
nicoo
600268c6e4 factor::miller_rabin::tests: Refactor 2020-07-05 00:01:40 +02:00
nicoo
0a1200bdb8 factor::miller_rabin: Add test for the largest 64b composite numbers 2020-07-05 00:01:37 +02:00
nicoo
308290325a factor::miller_rabin::is_prime: Fix bug
Montgomery<_> only works for odd n, so attempting to construct an instance
for an even number results in a panic!

The most obvious solution is to special-case even numbers.
2020-07-05 00:01:33 +02:00
nicoo
d2b43f49f9 factor::numeric::OverflowingAdd: Generate impls with a macro 2020-07-05 00:01:21 +02:00
nicoo
b25c77c5f9 factor::numeric: Generate implementations of DoubleInt with a macro 2020-07-05 00:01:21 +02:00
nicoo
f95f977f98 factor::numeric: Generate implementations of Int with a macro 2020-07-05 00:01:21 +02:00
nicoo
53954badd7 factor::numeric: Refactor away the use of {To,From}Primitives 2020-07-05 00:01:21 +02:00
nicoo
19a8231fb2 factor::numeric::Arithmetic: Rename associated type I to ModInt 2020-07-05 00:01:21 +02:00
nicoo
caa79a1261 factor::numeric: Split Int and DoubleInt traits 2020-07-05 00:01:21 +02:00
nicoo
28244413d1 factor::numeric: Document when to remove OverflowingAdd trait 2020-07-05 00:01:21 +02:00
nicoo
3f79be0219 factor::numeric: Use debug_assert! for runtime assertions. 2020-07-05 00:01:21 +02:00
nicoo
774feb0a40 factor::numeric: Generalise tests for Arithmetic trait 2020-07-05 00:01:21 +02:00
Alex Lyon
4d28f48ad9 factor: combine Montgomery and Montgomery32 2020-07-05 00:01:21 +02:00
nicoo
a440807e6c factor::miller_rabin: Use a specialized basis for 32b integers
~3% faster
2020-07-05 00:01:21 +02:00
nicoo
e68bb192f2 factor::numeric: Add a 32b Montgomery variant [WiP]
~32% faster
2020-07-05 00:01:21 +02:00
nicoo
43ee92c40f factor::numeric: Generalise modular inverse computation 2020-07-05 00:01:21 +02:00
Alex Lyon
bb01e67521
Merge pull request #1560 from shlomif/fix-grammar
[README] Correct some broken grammar & spelling.
2020-07-01 10:57:15 -07:00
Shlomi Fish
3f928a7612 [README] Revise some suboptimal phrasing.
Also incorporated the change commentary by @Arcterus. ( Thanks! ).
2020-06-29 22:45:30 +03:00
Alex Lyon
9de82d92b0
Merge pull request #1557 from nbraud/factor/issue_1556
factor::miller_rabin: Fix bug #1556
2020-06-24 04:53:32 -07:00
Alex Lyon
700d51a92b
Merge pull request #1528 from sylvestre/cp-no-deref
feature(cp) implement -P/--no-deference
2020-06-23 23:05:26 -07:00
nicoo
abf579975c factor::miller_rabin: Fix bug in primality test
Introduced in 6b9585b1 (#1525: Performance improvements for `factor`).
Closes #1556
2020-06-23 16:19:16 +02:00
nicoo
c5c86b00e9 factor::miller_rabin: Add tests reproducing #1556 2020-06-23 16:14:52 +02:00
Sylvestre Ledru
c7c2ae54b8
Merge pull request #1553 from rivy/fix.tests-factor
tests/factor ~ re-enable factor tests
2020-06-21 20:39:56 +02:00
Roy Ivy III
f3ee45171f tests/factor ~ re-enable factor tests (with additional detail for failures)
- probably fixes #1531 (via #1529) per @nbraud
2020-06-21 12:17:46 -05:00
Alex Lyon
ddd38403e6
Merge pull request #1552 from nbraud/factor/faster/table
Speed up factor::table
2020-06-20 13:55:14 -07:00
nicoo
8e040bbf1a factor::table: Optimise the size of the precomputed table
A too-large precomputed table actually slows down the program: we spend
time fetching it from disk and from memory (into the CPU's cache), and
larger prime factors are more unlikely to occur in random integers (prime p
occurs with probability ~1/p when sampling 64b numbers uniformly-at-random)

The new value was chosen after measuring the execution time (for all
integers between 2 and 10⁷) for a broad set of values:

| n    | time (s) |
|------|----------|
| 16   | 40.84    |
| 32   | 34.491   |
| 64   | 29.044   |
| 128  | 25.121   |
| 192  | 23.98    |
| 256  | 23.102   |
| 256  | 24.93    |
| 272  | 23.57    |
| 288  | 23.85    |
| 304  | 23.91    |
| 320  | 23.24    |
| 329  | 23.45    |
| 336  | 23.55    |
| 352  | 23.09    |
| 368  | 23.65    |
| 384  | 23.32    |
| 384  | 23.36    |
| 400  | 23.30    |
| 416  | 23.38    |
| 432  | 23.42    |
| 448  | 23.95    |
| 448  | 24.00    |
| 464  | 23.81    |
| 480  | 23.55    |
| 496  | 24.10    |
| 512  | 24.101   |
| 512  | 24.23    |
| 1027 | 29.864   |
2020-06-20 22:22:55 +02:00
nicoo
9d992b77b2 factor: Keep the primes table size in a single place 2020-06-20 22:22:55 +02:00
nicoo
b956e632e1 factor::table: Coalesce accesses to the factors table
~5.6% faster
2020-06-20 22:22:55 +02:00
Alex Lyon
c97c98bd2b
Merge pull request #1550 from nbraud/factor/rhofactor
factor::rho: Refactor for readability and fewer allocations
2020-06-20 06:17:33 -07:00
Sylvestre Ledru
2d62097843 feature(cp): Manage -P & -R 2020-06-20 10:49:15 +02:00
nicoo
0518e06053 factor::rho: Minor refactor for readability 2020-06-20 10:39:56 +02:00
nicoo
dacee413db factor::rho: Refactor to avoid unnecessary allocations 2020-06-20 10:39:56 +02:00
nicoo
71e1c52920 factor::Factors: Rename new() to one() 2020-06-20 10:39:56 +02:00
Sylvestre Ledru
280fafed8a feature(cp) implement -P/--no-deference 2020-06-20 09:38:39 +02:00
Alex Lyon
f33ffc73eb
Merge pull request #1549 from nbraud/factor/strong-pseudoprime-bug
factor: Fix very-rare bug in ρ
2020-06-19 16:46:59 -07:00
nicoo
45a1408fb0 fixup! factor: Add test exhibiting a bug in ρ 2020-06-19 15:28:01 +02:00
nicoo
9fe3de72f2 factor::rho: Fix very-unlikely bug (resulting in assertion failure)
This bug can only be triggered when:
- the Miller-Rabin test produces a divisor `d` (rare) ;
- n / d is prime.
2020-06-19 13:51:29 +02:00
nicoo
9eb944b6b9 factor: Add test exhibiting a bug in ρ
The test is repeated 20 times to make it overwhelmingly-likely to fail
(the bug itself is only triggered rarely)
2020-06-19 13:48:00 +02:00
nicoo
3a90e31307 factor::numeric::inv_mod_u64: Provide a more-helpful error message 2020-06-19 13:39:42 +02:00
Alex Lyon
02b419db5f
Merge pull request #1545 from sylvestre/vscode
vscode: install rust support & rla
2020-06-18 23:50:41 -07:00
Alex Lyon
486022307c
Merge pull request #1547 from nbraud/factor/faster/display
factors: Speed up displaying the results
2020-06-18 23:36:04 -07:00
nicoo
ef12991ee7 factors: Avoid repeatedly locking and flushing stdout
By default, stdout's LineWriter results one syscall per line, i.e. a billion
syscalls when factoring a billion numbers...

Buffering the output yields a ~28% speedup.
2020-06-18 16:45:40 -07:00
nicoo
2869248318 factor::Factors: Use a tree-based map internally
This eliminate the need for sorting the prime factors for display.
25% performance improvement after the changes from factor/montgomery.
2020-06-18 16:44:08 -07:00
nicoo
4b4d11b61a
factor: Add/update copyright notices as necessary (#1546) 2020-06-18 21:38:28 +02:00
Alex Lyon
6105cce69a
Merge pull request #1529 from nbraud/factor/montgomery
factor: Faster modular arithmetic with the Montgomery transform
2020-06-18 09:19:12 -07:00