LLVM-Examples

LLVM Examples and Code samples. LLVM Passes. Based on llvm-project

# llvm cmake
cmake -G "Ninja" build \
  -DLLVM_ENABLE_PROJECTS="llvm;compiler-rt;clang;clang-tools-extra" \
  -DCMAKE_BUILD_TYPE=Release \
  -DLLVM_ENABLE_ASSERTIONS=ON \
  -DLLVM_CCACHE_BUILD=OFF \
  -DLLVM_BUILD_TESTS=ON \
  -DLLVM_INSTALL_UTILS=ON \
  -B build -S llvm

Installing from Docker

Check build commands in the Dockerfile for more information on installing LLVM on local machine.

$ docker build -f DockerFile -t prodrelworks/llvm-examples:latest .
$ docker run --name llvm-examples --ulimit stack=10000000:10000000 \
  --cpus=4 --memory=20g -it prodrelworks/llvm-examples:latest

Examples & Implementations :

• llvm::LoopInfo in the runOnModule
• Analysing CFGs with LLVM
• A tutorial on how to write a compiler using LLVM

References & Links :

• LLVM Get Started

• Learning Compilers

• Learning Compilers/LLVM: How to start?

• LLVM-12 Book

• LLVM Passes

• LLVM GitHub Monorepo

• Clang AST LLVM

• Legacy Pass Example : See folder.

  • LLVM : What is a pass? Legacy Pass Example

• New LLVM Pass Manager :

  • LLVM : New Pass Manager
  • LLVM : Writing a new pass

• For function paraments as operands, you can get it get it via Function Argumentslist()

  • Function Parameters LLVM Function
  • Value Reference
  • User class : for getnumoperands, getoperands

• Some other differences are listed here. Even C++ one is quadratic probed.

  • https://llvm.org/docs/ProgrammersManual.html#llvm-adt-densemap-h

• Where is "emit-llvm"? ASMWritter AsmWritter.cpp.

  • https://github.com/llvm-mirror/llvm/blob/master/tools/gold/gold-plugin.cpp#L232
  • https://www.cs.cornell.edu/~asampson/blog/llvm.html

• LLVM Data Structures :

  • https://llvm.org/docs/ProgrammersManual.html#picking-the-right-data-structure-for-a-task

• LLVM RTTI :

  • https://llvm.org/docs/HowToSetUpLLVMStyleRTTI.html#id1

• Inspection & Traversal over CFG in IR :

  • Inspection & Traversal Routines over CFG
  • LLVM : Making simple manipulations