Can one construct a "good" hash function using CRC32C as a base.

Posted by DavidD on Stack Overflow See other posts from Stack Overflow or by DavidD
Published on 2010-04-22T21:43:17Z Indexed on 2010/04/22 21:53 UTC
Read the original article Hit count: 287

Filed under:

crc32

|

hash

|

intel

|

sse

Given that SSE 4.2 (Intel Core i7 & i5 parts) includes a CRC32 instruction, it seems reasonable to investigate whether one could build a faster general-purpose hash function. According to this only 16 bits of a CRC32 are evenly distributed. So what other transformation would one apply to overcome that?

David

© Stack Overflow or respective owner

Related posts about crc32

Javascript crc32 function and PHP crc32 not matching

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello everyone, I'm working on a webapp where I want to match some crc32 values that have been generated server side in PHP with some crc32 values that I am generating in Javascript. Both are using the same input string but returning different values. I found a crc32 javascript library on webtoolkit… >>> More
openssl CRC32 calculation

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi all, I have seen some of the other questions here about the CRC 32 calculation. But none were satisfactory for me, hence this. Does openssl libraries have any api support for calculating the CRC32? I am already using openssl for SHA1, so would prefer to use it than link in one more library for… >>> More
crc32 decrypt short string

as seen on Stack Overflow - Search for 'Stack Overflow'
I am retrieving lists of crc32 hashes that contain names of files, not there contents. I need to be able to decrypt the strings which are hashed names like "vacationplans_2010.txt" which are less then 25 characters long. is this possible? >>> More
PHP CRC32 length output

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi! Is there anything that can make the returned length of the PHP CRC32 function to vary? Thanks! >>> More
PHP crc32() only numbers

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a MD5 hash: 10f86782177490f2ac970b8dc4c51014 http://www.fileformat.info/tool/hash.htm?text=10f86782177490f2ac970b8dc4c51014 Result: c74e16d9 but PHP: crc32('10f86782177490f2ac970b8dc4c51014'); Result: -951183655 I don't understand! >>> More

Related posts about hash

Problem with hash function: hash(1) == hash(1.0)

as seen on Stack Overflow - Search for 'Stack Overflow'
I have an instance of dict with ints, floats, strings as keys, but the problem is when there are a as int and b as float, and float(a) == b, then their hash values are the same, and thats what I do NOT want to get because I need unique hash vales for this cases in order to get corresponding values… >>> More
Hash table vs Hash list vs Hash tree?

as seen on Stack Overflow - Search for 'Stack Overflow'
What property makes Hash table, Hash list and Hash tree different from each other? Which one is used when? When is table superior than tree. >>> More
Constructing a hash table/hash function.

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I would like to construct a hash table that looks up keys in sequences (strings) of bytes ranging from 1 to 15 bytes. I would like to store an integer value, so I imagine an array for hashing would suffice. I'm having difficulty conceptualizing how to construct a hash function such that given… >>> More
Hash of unique value = unique hash?

as seen on Stack Overflow - Search for 'Stack Overflow'
Theoretically does hashing a unique value yield a unique value? Let's say I have a DB table with 2 columns: id and code. id is an auto-incrementing int and code is a varchar. If I do ... $code = sha1($id); ... and then store $code into the same row as $id. Will my code column be unique as well… >>> More
EMERGENCY - Major Problems After Perl Module Installed via WHM

as seen on Stack Overflow - Search for 'Stack Overflow'
I attempted to install the perl module Net::Twitter::Role::API::Lists using WHM and after doing so my whole site came down. It seems that something that was updated with the install isn't functioning correctly and since our website it written in Perl none of our site scripts will run. In almost 8… >>> More