LLVMääIR

LLVM IR stands for Low Level Virtual Machine Intermediate Representation. It is a well-defined, low-level representation of program code used by the LLVM compiler infrastructure. LLVM IR acts as a common language that different front-end compilers (for languages like C, C++, Swift, Rust, etc.) can translate their source code into. This intermediate representation is then processed by LLVM's back-end optimizers and code generators, which can target various architectures like x86, ARM, and others.

The design of LLVM IR prioritizes clarity, simplicity, and ease of optimization. It is a static single assignment (SSA) form, meaning each variable is assigned a value exactly once. This property greatly simplifies many compiler optimization passes. LLVM IR is typically represented in a human-readable assembly-like text format, but it can also be serialized into a compact binary format for faster loading and saving.

Key features of LLVM IR include its instruction set, which is relatively simple and orthogonal, and its type system, which is rich enough to represent complex data structures. The IR is designed to be language-agnostic, allowing for powerful cross-language optimizations and enabling LLVM to serve as a foundational technology for a wide range of programming languages and tools. Compilers that target LLVM typically generate IR, which is then passed to LLVM's optimization passes before being compiled into native machine code or other target formats.