Mapping High Level Constructs to LLVM IR

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This is a gitbook dedicated to providing a description on how LLVM based compilers map high-level language constructs into the LLVM intermediate representation (IR).

This document targets people interested in how modern compilers work and want to learn how high-level language constructs can be implemented. Currently the books focuses on C and C++, but contributions about other languages targeting LLVM are highly welcome. This document should help to make the learning curve less steep for aspiring LLVM users.

For the sake of simplicity, we’ll be working with a 32-bit target machine so that pointers and word-sized operands are 32-bits. Also, for the sake of readability we do not mangle (encode) names. Rather, they are given simple, easy-to-read names that reflect their purpose. A production compiler for any language that supports overloading would generally need to mangle the names so as to avoid conflicts between symbols.


The repository for this document is hosted on github. All contributions are welcome. If you find an error file an Issue or fork the repository and create a pull-request.