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                        Opcode analysis program

This program is designed to help look at the frequency of opcodes, and the

occurance of groups of opcodes together.

This can also be done on the command line, but it was felt, at the time a C

program might be a quicker way. 3 hours later, it's not the author's intention

to now try doing this with sed, awk and sort.

The list of instructions/opcodes should be one per line, with a newline at the

end. There is no capability to look at register numbers. An example of

generating suitable input to the program is given below.

At the moment this program only analyses up to quadruples, and is not codeded

in such a way that makes an arbitrary number of instruction groups easily

testable. Fix this if you like.

There are no options when running the program. It will simply spit out a list

of individual opcodes, then list of pairs, triples and quadruples.

Compile the program with

$ make all

Generate a list of opcodes from a large set of code, with the following:

Disassemble an application with:

$ or32-elf-objdump -d app.elf > app.dis

The generate a list of opcodes with

$ grep "l\." app.dis | cut -d '.' -f 2 | cut -d ' ' -f 1 > opcodes

Call the program and pass the file with the list of opcodes as the first

argument. It's best to pipe the output it generates to a file:

$ opcodeanalysis opcodes > opcodes.analsys

Things that might be good:

* Actually verifying the pair/triple/quadruple results are correct/true

* Limiting the output of set results to the first 5/10/20

* Provide an option to perform register analysis, also.

* Generate CSV formatted output

Julius Baxter

14 July, 2010