Chapter 4: TableGen Development
TableGen is a domain-specific language (DSL) that was originally developed in Low-Level Virtual Machine (LLVM) to express processors' instruction set architecture (ISA) and other hardware-specific details, similar to the GNU Compiler Collection's (GCC's) Machine Description (MD). Thus, many people learn TableGen when they're dealing with LLVM's backend development. However, TableGen is not just for describing hardware specifications: it is a general DSL useful for any tasks that involve non-trivial static and structural data. LLVM has also been using TableGen on parts outside the backend. For example, Clang has been using TableGen for its command-line options management. People in the community are also exploring the possibility to implement InstCombine rules (LLVM's peephole optimizations) in TableGen syntax.
Despite TableGen's universality, the language's core syntax has never been widely understood by many...
