LLVM-Clang-Examples

A collection of code based on LLVM/Clang compilation libraries and tools.

There are also some useful tutorials about LLVM/clang in directory tutorials/.

To install llvm, you can use the installer script install-llvm-5.0.1.sh that can be found in directory utils/.

E.g. use $ ./install-llvm-5.0.1.sh 4 ~/ to build llvm-5.0.1 using 4 cores in your home directory.

Contents

• Tutorials
• Custom class supporting LLVM RTTI
• C AST Interpreter
• Comments Extractor
• Dataflow Points-to Analysis
• Use CalledValuePropagationPass in your tool
• Break ConstantExpr
• Unify Function Exits
• Run an LLVM Pass with Clang
• JIT for brainfuck
• Taint Propagation

Tutorials

• LLVM IR Tutorial - Phis, GEPs and other things, oh my!
• How to Write a Clang Static Analyzer Checker in 24 Hours
• Scalar Evolution Demystified

Custom class supporting LLVM RTTI

Sample code used to demonstrate how to set up LLVM-Style RTTI for your custom class hierarchy.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/custom-class-support-llvm-rtti

C AST Interpreter

A basic tiny C language interpreter based on Clang.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/c-ast-interpreter

Comments Extractor

A simple tool based on clang's libtooling to grab all the comments from C source code.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/comments-extractor

Dataflow Points-to Analysis

An LLVM pass that implements a flow-sensitive, field- and context-insensitive points-to analysis via dataflow, computing the points-to set for each variable at each distinct program point.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/dataflow-points-to-analysis

Use CalledValuePropagationPass in your tool

Sample code used to demonstrate how to call CalledValuePropagationPass in your own tool based LLVM.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/use-calledvaluepropagation-in-your-tool

Break ConstantExpr

This BreakConstantExpr is a module pass that converts all constant expressions into instructions.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/break-constantexpr

Unify Function Exits

This UnifyFunctionExits module pass is just a wrapper for UnifyFunctionExitNodes function pass, used to ensure that functions have at most one return instruction in them.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/unify-functionexits

Run an LLVM Pass with Clang

Sample code used to demonstrate how to run your LLVM Pass with Clang.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/clang-pass

JIT for brainfuck

A JIT using LLVM for brainfuck language.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/building-a-JIT-for-BF

Taint Propagation

An LLVM transform pass implements a flow-sensitive, field- and context-insensitive taint propagation based on classic dataflow analysis.

For detail, see https://github.com/Enna1/LLVM-Clang-Examples/tree/master/taint-propagation