Utility: match

Mike's Junk Drawer Random stuff. You might not find anything interesting, but this is where I keep stuff I want handy.

Articles

Utility: match
Sharing a little utility called match which I use in conjunction with uniq.

Open Source and Console Games
The free and open source software which we gladly take advantage of can be thought of as the proverbial "shoulder of giants". When we forget what brought us the advantages to get where we are, we do a disservice to ourselves and the health of our industry, and thus ultimately a disservice to our shareholders and customers.

Understanding Strict Aliasing
Strict aliasing has been part of C programming for the better part of the last decade but a thorough understanding of the details of this feature is still clouded in mystery for many programmers. Examine detailed examples and some perculiarities of GCC's implementation.

Demystifying The Restrict Keyword
Optimizing data access is a critical part of good performance. Read on to find out how to use the restrict keyword to open up a whole class of optimizations that were previously impossible for a C compiler.

A Practical GCC Trick To Use During Optimization
Splitting a basic block (by force) Warning: This is a trick to use during optimization. It is not documented nor gauranteed to work across multiple platforms or different revisions of the compiler. Many programmers will say that this non-portable code...

Performance and Good Data Design
What follows are some simple rules of thumb that programmers can follow to create a solid pipeline from the content creators to the screen and speakers.

Links

Legal

Content Copyright © 2006 by Mike Acton. All Rights Reserved.

This site uses the Movable Type 3.2 content engine.

This site uses the phpBB bulletin board engine Copyright © 2001, 2005 phpBB Group.

Cell Broadband Engine is a trademark of Sony Computer Entertainment, Inc

PowerPC is a trademark of International Business Machines Corporation.

Linux is a registered trademark of Linus Torvalds in the U.S. and other countries.

Macintosh, and Mac are registered trademarks of Apple Computer, Inc

All other trademarks are the property of their respective owners.

Utility: match

Mike Acton
April 07, 2007

Update! If fixed up all the greater-than and less-than symbols in this entry. I didn't make much sense before. I always forget to change those up in the HTML.

I'm just sharing a little utility I use all the time called match.

Usage: ./match [-h] <source_file> <uniq_file>

For each line in <source_file> print the index to the 
first matching line in <uniq_file>.

[-h] Print results in 32 bit hexidecimal (default is decimal)

Note: The max line width supported is 4095 characters.
Note: Maximum number of lines supported is (2^32)

If I have a source file of data represented as text (as I often do because it's often easier for me to read binary dumps in a text editor than a special "hex editor"), I use match to create a table of indices to unique lines (often these correspond to 128 bits since that's the size of an SPU register).

I commonly use it like so (given I have a file called "source_file")

sort source_file | uniq > uniq_file
match source_file uniq_file

Now I have a handy table of indices!

Download: match.c

ABOUT THE AUTHOR

Mike Acton is the director and adminstrator of CellPerformance, is dedicated to helping the Cell community as much as possible and plies his trade developing technology for PS3 games.

Mike has made regular appearances as a speaker at SCEA develpment conferences and other events. Mike Acton is not a framework-happy C++ programmer. He actually likes C. And assembly. In his spare time he develops hardware on FPGAs in VHDL.

He prefers vi.

Also check out the CellPerformance main site, which has additional articles written by Mike Acton.