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Further MD5 optimizations

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performance-simd-rust
Inga 🏳‍🌈 8 years ago
parent d9c2cad4b6
commit e5c1e743bc
2 changed files with 67 additions and 55 deletions
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  1. 17
      README.md
  2. 103
      WhiteRabbit/MD5Digest.cs

17
README.md
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@ -41,19 +41,28 @@ Anagrams generation is not parallelized, as even single-threaded performance for
Multi-threaded performance with RyuJIT (.NET 4.6, 64-bit system) on quad-core Sandy Bridge @2.8GHz is as follows:
* If only phrases of at most 4 words are allowed, then it takes **around 2 seconds** to find and check all 7433016 anagrams; all hashes are solved in first 0.4 seconds.
* If only phrases of at most 4 words are allowed, then it takes **less than 2 seconds** to find and check all 7433016 anagrams; all hashes are solved in first 0.3 seconds.
* If phrases of 5 words are allowed as well, then it takes around 5.5 minutes to find and check all 1348876896 anagrams; all hashes are solved in first 8.5 seconds.
* If phrases of 5 words are allowed as well, then it takes around 5 minutes to find and check all 1348876896 anagrams; all hashes are solved in first 7.5 seconds.
Most of time is spent on MD5 computations for correct anagrams, so there is not a lot to optimize further.
* If phrases of 6 words are allowed as well, then "more difficult" hash is solved in 9 seconds, "easiest" in 50 seconds, and "hard" in 2 minutes.
* If phrases of 6 words are allowed as well, then "more difficult" hash is solved in 8 seconds, "easiest" in 48 seconds, and "hard" in less than 2 minutes.
* If phrases of 7 words are allowed as well, then "more difficult" hash is solved in 56 seconds, "easiest" in 7 minutes, and "hard" in 18 minutes.
* If phrases of 7 words are allowed as well, then "more difficult" hash is solved in 46 seconds, "easiest" in less than 6 minutes, and "hard" in around 15 minutes.
Note that all measurements were done on a Release build; Debug build is significantly slower.
For comparison, certain other solutions available on GitHub seem to require 3 hours to find all 3-word anagrams. This solution is faster by 5-7 orders of magnitude (it finds and checks all 4-word anagrams in 1/2000th fraction of time required for other solution just to find all 3-word anagrams, with no MD5 calculations).
Conditional compilation symbols
===============================
* Define `BIG_ENDIAN` if you plan to run this on big-endian PC; this will disable certain MD5 optimizations that only produce correct result on little-endian PCs.
* Define `SINGLE_THREADED` to use standard enumerables instead of ParallelEnumerable.
* Define `DEBUG`, or build in debug mode, to get the total number of anagrams (not optimized, memory-hogging).
Implementation notes
====================

103
WhiteRabbit/MD5Digest.cs
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@ -4,6 +4,7 @@
/**
* Code taken from BouncyCastle and optimized for specific constraints (e.g. input is always larger than 4 bytes and smaller than 52 bytes).
* Further optimization: input could be assumed to be smaller than 27 bytes (original phrase contains 18 letters, so that allows anagrams of 9 words)
* base implementation of MD4 family style digest as outlined in
* "Handbook of Applied Cryptography", pages 344 - 347.
* implementation of MD5 as outlined in "Handbook of Applied Cryptography", pages 346 - 347.
@ -14,26 +15,28 @@
{
var length = input.Length;
var xBytes = new byte[4 * 14];
Buffer.BlockCopy(input, 0, xBytes, 0, length);
xBytes[length] = 128;
var xUints = new uint[8]; // it seems that alignment helps
#if BIG_ENDIAN
xUints[0] = LE_To_UInt32(xBytes, 4 * 0);
xUints[1] = LE_To_UInt32(xBytes, 4 * 1);
xUints[2] = LE_To_UInt32(xBytes, 4 * 2);
xUints[3] = LE_To_UInt32(xBytes, 4 * 3);
xUints[4] = LE_To_UInt32(xBytes, 4 * 4);
xUints[5] = LE_To_UInt32(xBytes, 4 * 5);
xUints[6] = LE_To_UInt32(xBytes, 4 * 6);
#else
Buffer.BlockCopy(input, 0, xUints, 0, length);
#endif
xUints[length >> 2] |= (uint)128 << (8 * (length & 3));
var x0 = LE_To_UInt32(xBytes, 4 * 0);
var x1 = LE_To_UInt32(xBytes, 4 * 1);
var x2 = LE_To_UInt32(xBytes, 4 * 2);
var x3 = LE_To_UInt32(xBytes, 4 * 3);
var x4 = LE_To_UInt32(xBytes, 4 * 4);
var x5 = LE_To_UInt32(xBytes, 4 * 5);
var x6 = LE_To_UInt32(xBytes, 4 * 6);
var x7 = LE_To_UInt32(xBytes, 4 * 7);
var x8 = LE_To_UInt32(xBytes, 4 * 8);
var x9 = LE_To_UInt32(xBytes, 4 * 9);
var x10 = LE_To_UInt32(xBytes, 4 * 10);
var x11 = LE_To_UInt32(xBytes, 4 * 11);
var x12 = LE_To_UInt32(xBytes, 4 * 12);
var x13 = LE_To_UInt32(xBytes, 4 * 13);
var x0 = xUints[0];
var x1 = xUints[1];
var x2 = xUints[2];
var x3 = xUints[3];
var x4 = xUints[4];
var x5 = xUints[5];
var x6 = xUints[6];
var x14 = (uint)(length << 3);
uint x15 = 0;
uint a = 0x67452301;
uint b = 0xefcdab89;
@ -47,66 +50,66 @@
a = LeftRotate(x4 + 0xf57c0faf + a + ((b & c) | (~b & d)), 7, 32 - 7) + b;
d = LeftRotate(x5 + 0x4787c62a + d + ((a & b) | (~a & c)), 12, 32 - 12) + a;
c = LeftRotate(x6 + 0xa8304613 + c + ((d & a) | (~d & b)), 17, 32 - 17) + d;
b = LeftRotate(x7 + 0xfd469501 + b + ((c & d) | (~c & a)), 22, 32 - 22) + c;
a = LeftRotate(x8 + 0x698098d8 + a + ((b & c) | (~b & d)), 7, 32 - 7) + b;
d = LeftRotate(x9 + 0x8b44f7af + d + ((a & b) | (~a & c)), 12, 32 - 12) + a;
c = LeftRotate(x10 + 0xffff5bb1 + c + ((d & a) | (~d & b)), 17, 32 - 17) + d;
b = LeftRotate(x11 + 0x895cd7be + b + ((c & d) | (~c & a)), 22, 32 - 22) + c;
a = LeftRotate(x12 + 0x6b901122 + a + ((b & c) | (~b & d)), 7, 32 - 7) + b;
d = LeftRotate(x13 + 0xfd987193 + d + ((a & b) | (~a & c)), 12, 32 - 12) + a;
b = LeftRotate(0xfd469501 + b + ((c & d) | (~c & a)), 22, 32 - 22) + c;
a = LeftRotate(0x698098d8 + a + ((b & c) | (~b & d)), 7, 32 - 7) + b;
d = LeftRotate(0x8b44f7af + d + ((a & b) | (~a & c)), 12, 32 - 12) + a;
c = LeftRotate(0xffff5bb1 + c + ((d & a) | (~d & b)), 17, 32 - 17) + d;
b = LeftRotate(0x895cd7be + b + ((c & d) | (~c & a)), 22, 32 - 22) + c;
a = LeftRotate(0x6b901122 + a + ((b & c) | (~b & d)), 7, 32 - 7) + b;
d = LeftRotate(0xfd987193 + d + ((a & b) | (~a & c)), 12, 32 - 12) + a;
c = LeftRotate(x14 + 0xa679438e + c + ((d & a) | (~d & b)), 17, 32 - 17) + d;
b = LeftRotate(x15 + 0x49b40821 + b + ((c & d) | (~c & a)), 22, 32 - 22) + c;
b = LeftRotate(0x49b40821 + b + ((c & d) | (~c & a)), 22, 32 - 22) + c;
a = LeftRotate(x1 + 0xf61e2562 + a + ((b & d) | (c & ~d)), 5, 32 - 5) + b;
d = LeftRotate(x6 + 0xc040b340 + d + ((a & c) | (b & ~c)), 9, 32 - 9) + a;
c = LeftRotate(x11 + 0x265e5a51 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
c = LeftRotate(0x265e5a51 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
b = LeftRotate(x0 + 0xe9b6c7aa + b + ((c & a) | (d & ~a)), 20, 32 - 20) + c;
a = LeftRotate(x5 + 0xd62f105d + a + ((b & d) | (c & ~d)), 5, 32 - 5) + b;
d = LeftRotate(x10 + 0x2441453 + d + ((a & c) | (b & ~c)), 9, 32 - 9) + a;
c = LeftRotate(x15 + 0xd8a1e681 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
d = LeftRotate(0x2441453 + d + ((a & c) | (b & ~c)), 9, 32 - 9) + a;
c = LeftRotate(0xd8a1e681 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
b = LeftRotate(x4 + 0xe7d3fbc8 + b + ((c & a) | (d & ~a)), 20, 32 - 20) + c;
a = LeftRotate(x9 + 0x21e1cde6 + a + ((b & d) | (c & ~d)), 5, 32 - 5) + b;
a = LeftRotate(0x21e1cde6 + a + ((b & d) | (c & ~d)), 5, 32 - 5) + b;
d = LeftRotate(x14 + 0xc33707d6 + d + ((a & c) | (b & ~c)), 9, 32 - 9) + a;
c = LeftRotate(x3 + 0xf4d50d87 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
b = LeftRotate(x8 + 0x455a14ed + b + ((c & a) | (d & ~a)), 20, 32 - 20) + c;
a = LeftRotate(x13 + 0xa9e3e905 + a + ((b & d) | (c & ~d)), 5, 32 - 5) + b;
b = LeftRotate(0x455a14ed + b + ((c & a) | (d & ~a)), 20, 32 - 20) + c;
a = LeftRotate(0xa9e3e905 + a + ((b & d) | (c & ~d)), 5, 32 - 5) + b;
d = LeftRotate(x2 + 0xfcefa3f8 + d + ((a & c) | (b & ~c)), 9, 32 - 9) + a;
c = LeftRotate(x7 + 0x676f02d9 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
b = LeftRotate(x12 + 0x8d2a4c8a + b + ((c & a) | (d & ~a)), 20, 32 - 20) + c;
c = LeftRotate(0x676f02d9 + c + ((d & b) | (a & ~b)), 14, 32 - 14) + d;
b = LeftRotate(0x8d2a4c8a + b + ((c & a) | (d & ~a)), 20, 32 - 20) + c;
a = LeftRotate(x5 + 0xfffa3942 + a + (b ^ c ^ d), 4, 32 - 4) + b;
d = LeftRotate(x8 + 0x8771f681 + d + (a ^ b ^ c), 11, 32 - 11) + a;
c = LeftRotate(x11 + 0x6d9d6122 + c + (d ^ a ^ b), 16, 32 - 16) + d;
d = LeftRotate(0x8771f681 + d + (a ^ b ^ c), 11, 32 - 11) + a;
c = LeftRotate(0x6d9d6122 + c + (d ^ a ^ b), 16, 32 - 16) + d;
b = LeftRotate(x14 + 0xfde5380c + b + (c ^ d ^ a), 23, 32 - 23) + c;
a = LeftRotate(x1 + 0xa4beea44 + a + (b ^ c ^ d), 4, 32 - 4) + b;
d = LeftRotate(x4 + 0x4bdecfa9 + d + (a ^ b ^ c), 11, 32 - 11) + a;
c = LeftRotate(x7 + 0xf6bb4b60 + c + (d ^ a ^ b), 16, 32 - 16) + d;
b = LeftRotate(x10 + 0xbebfbc70 + b + (c ^ d ^ a), 23, 32 - 23) + c;
a = LeftRotate(x13 + 0x289b7ec6 + a + (b ^ c ^ d), 4, 32 - 4) + b;
c = LeftRotate(0xf6bb4b60 + c + (d ^ a ^ b), 16, 32 - 16) + d;
b = LeftRotate(0xbebfbc70 + b + (c ^ d ^ a), 23, 32 - 23) + c;
a = LeftRotate(0x289b7ec6 + a + (b ^ c ^ d), 4, 32 - 4) + b;
d = LeftRotate(x0 + 0xeaa127fa + d + (a ^ b ^ c), 11, 32 - 11) + a;
c = LeftRotate(x3 + 0xd4ef3085 + c + (d ^ a ^ b), 16, 32 - 16) + d;
b = LeftRotate(x6 + 0x4881d05 + b + (c ^ d ^ a), 23, 32 - 23) + c;
a = LeftRotate(x9 + 0xd9d4d039 + a + (b ^ c ^ d), 4, 32 - 4) + b;
d = LeftRotate(x12 + 0xe6db99e5 + d + (a ^ b ^ c), 11, 32 - 11) + a;
c = LeftRotate(x15 + 0x1fa27cf8 + c + (d ^ a ^ b), 16, 32 - 16) + d;
a = LeftRotate(0xd9d4d039 + a + (b ^ c ^ d), 4, 32 - 4) + b;
d = LeftRotate(0xe6db99e5 + d + (a ^ b ^ c), 11, 32 - 11) + a;
c = LeftRotate(0x1fa27cf8 + c + (d ^ a ^ b), 16, 32 - 16) + d;
b = LeftRotate(x2 + 0xc4ac5665 + b + (c ^ d ^ a), 23, 32 - 23) + c;
a = LeftRotate(x0 + 0xf4292244 + a + (c ^ (b | ~d)), 6, 32 - 6) + b;
d = LeftRotate(x7 + 0x432aff97 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
d = LeftRotate(0x432aff97 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
c = LeftRotate(x14 + 0xab9423a7 + c + (a ^ (d | ~b)), 15, 32 - 15) + d;
b = LeftRotate(x5 + 0xfc93a039 + b + (d ^ (c | ~a)), 21, 32 - 21) + c;
a = LeftRotate(x12 + 0x655b59c3 + a + (c ^ (b | ~d)), 6, 32 - 6) + b;
a = LeftRotate(0x655b59c3 + a + (c ^ (b | ~d)), 6, 32 - 6) + b;
d = LeftRotate(x3 + 0x8f0ccc92 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
c = LeftRotate(x10 + 0xffeff47d + c + (a ^ (d | ~b)), 15, 32 - 15) + d;
c = LeftRotate(0xffeff47d + c + (a ^ (d | ~b)), 15, 32 - 15) + d;
b = LeftRotate(x1 + 0x85845dd1 + b + (d ^ (c | ~a)), 21, 32 - 21) + c;
a = LeftRotate(x8 + 0x6fa87e4f + a + (c ^ (b | ~d)), 6, 32 - 6) + b;
d = LeftRotate(x15 + 0xfe2ce6e0 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
a = LeftRotate(0x6fa87e4f + a + (c ^ (b | ~d)), 6, 32 - 6) + b;
d = LeftRotate(0xfe2ce6e0 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
c = LeftRotate(x6 + 0xa3014314 + c + (a ^ (d | ~b)), 15, 32 - 15) + d;
b = LeftRotate(x13 + 0x4e0811a1 + b + (d ^ (c | ~a)), 21, 32 - 21) + c;
b = LeftRotate(0x4e0811a1 + b + (d ^ (c | ~a)), 21, 32 - 21) + c;
a = LeftRotate(x4 + 0xf7537e82 + a + (c ^ (b | ~d)), 6, 32 - 6) + b;
d = LeftRotate(x11 + 0xbd3af235 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
d = LeftRotate(0xbd3af235 + d + (b ^ (a | ~c)), 10, 32 - 10) + a;
c = LeftRotate(x2 + 0x2ad7d2bb + c + (a ^ (d | ~b)), 15, 32 - 15) + d;
b = LeftRotate(x9 + 0xeb86d391 + b + (d ^ (c | ~a)), 21, 32 - 21) + c;
b = LeftRotate(0xeb86d391 + b + (d ^ (c | ~a)), 21, 32 - 21) + c;
return new[]
{

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