In order to decouple the compiler into several tools, the LLVM design typically enforces component interaction to happen at a high level of abstraction. It segregates different components into separate libraries; it is written in C++ using object-oriented paradigms and a pluggable pass interface is available, allowing easy integration of transformations and optimizations throughout the compilation pipeline.
The LLVM and Clang logic is carefully organized into the following libraries:
libLLVMCore: This contains all the logic related to the LLVM IR: IR construction (data layout, instructions, basic blocks, and functions) and the IR verifier. It also provides the pass manager.libLLVMAnalysis: This groups several IR analysis passes, such as alias analysis, dependence analysis, constant folding, loop info, memory dependence analysis, and instruction simplify.libLLVMCodeGen: This implements target-independent code generation...