llvm-cat

Concatenate Bitcode files

$ llvm-cat [path/to/file1.bc] [path/to/file2.bc] -o [path/to/out.bc]

llvm-cat [options]

-help
    Display available options and exit.

-version
    Display the LLVM version and exit.

llvm-cat is a command-line utility that concatenates LLVM bitcode files. It is part of the LLVM (Low Level Virtual Machine) toolchain, a collection of modular and reusable compiler and toolchain technologies. llvm-cat takes one or more LLVM bitcode files (.bc files) as input and outputs a single, combined bitcode file to standard output. This can be useful for creating larger modules from smaller parts or assembling a program from different compilation units into a single bitcode representation for further optimization or analysis.

The primary use case involves working with LLVM's intermediate representation (IR). By combining bitcode files, you can perform whole-program analysis or optimization passes. It is important to note that llvm-cat performs simple concatenation and doesn't handle symbol resolution or conflict resolution between input files. Care must be taken to ensure that the resulting combined bitcode file is semantically correct and doesn't contain conflicts.

llvm-cat performs a simple concatenation of bitcode files. It does not resolve symbol conflicts or perform any semantic analysis. The user is responsible for ensuring that the input files are compatible and that the resulting bitcode file is valid.

To combine two bitcode files (file1.bc and file2.bc) into a single bitcode file named combined.bc:

llvm-cat file1.bc file2.bc > combined.bc

llvm-cat has been part of the LLVM toolchain for a long time. It evolved alongside LLVM, primarily as a utility for developers working with bitcode manipulation. Its development and usage are closely linked to the evolution of the LLVM IR format and related tools. It serves as a building block in complex LLVM based workflows.

llvm-dis(1), opt(1)