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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.

It takes input from a file, and generates output to stdout via printf.

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.

Two output formats are possible - switchable by the #define DISPLAY options in

the C source.

1) Human readable output, enabled by uncommenting the DISPLAY_STRING define

2) CSV output, enabled by uncommenting the DISPLAY_CSV define

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, in one of

the two formats described above.

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

* Provide an option to perform register analysis, also.

Julius Baxter

15 July, 2010