Logger compiler

Description

This project implements simple logger compiler based on clang-13.

For now, compiler just instruments every instruction that returns integer value and prints to the log file the values these instructions returned in next format:

llvm_function_ptr_1 value
llvm_function_ptr_2 value
...

Also, compiler dumped a def-use chain graph of every function in dot format.

Moreover, project contains patcher to insert collected runtime information to the def-use chain of the function.

How to build

To build this project, you need installed next requirements: llvm-13 headers, clang-13, clang++-13, llvm-config-13.

Follow next steps from project's root:

1. mkdir build && cd build
2. cmake -DLLVM_DIR="/usr/lib/llvm-13/lib/cmake/llvm" -DCMAKE_C_COMPILER=clang-13 -DCMAKE_CXX_COMPILER=clang++-13. But replace -DLLVM_DIR value with path to your llvm's directory.
3. make

How to run

Running consists of three main steps:

1. Static code instrumentation:

   There's logger_cc to instrument code. You can run ./logger_cc binary as usual clang compiler. For example, to compile given tests, you should execute (from projects build directory):

   ./logger_cc ../tests/test.cpp ../tests/test-modules.cpp -o test

   This will produce both: result binary file and *.dot files with def-use chain for each translation module.

2. Collecting runtime values information

   To collect the data just run ./test (or any other binary produced by compiler on step #1). Then, ./build/instruction_values.log file with collected info will appear.

3. Combining all together

   Now, we need to unite runtime values information from step #2 with def-use chain graph from step #1. To do this, just run (from projects build directory):

   ./pathcher [path_to_produced_dot_file] [path_to_log_file_with_rt_info]

   This script will insert rt values info to dot file.

   Note: that script doesn't create new *.dot files, it replaces existing one.

   Then, you can compile dot file like usual:

   dot -Tpng [path_to_produced_dot_file] -o [path_to_create_output_file]

   Note: if instruction was called several times (for ex. in recursive function), then instruction values will be listed in comma-separated list in graph.