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llvm-extract - extract a function from an LLVM module

SYNOPSIS

:program:`llvm-extract` [options] --func function-name [filename]

DESCRIPTION

The :program:`llvm-extract` command takes the name of a function and extracts it from the specified LLVM bitcode file. It is primarily used as a debugging tool to reduce test cases from larger programs that are triggering a bug.

In addition to extracting the bitcode of the specified function, :program:`llvm-extract` will also remove unreachable global variables, prototypes, and unused types.

The :program:`llvm-extract` command reads its input from standard input if filename is omitted or if filename is -. The output is always written to standard output, unless the -o option is specified (see below).

OPTIONS

-f

Enable binary output on terminals. Normally, :program:`llvm-extract` will refuse to write raw bitcode output if the output stream is a terminal. With this option, :program:`llvm-extract` will write raw bitcode regardless of the output device.

--func function-name

Extract the function named function-name from the LLVM bitcode. May be specified multiple times to extract multiple functions at once.

--rfunc function-regular-expr

Extract the function(s) matching function-regular-expr from the LLVM bitcode. All functions matching the regular expression will be extracted. May be specified multiple times.

--glob global-name

Extract the global variable named global-name from the LLVM bitcode. May be specified multiple times to extract multiple global variables at once.

--rglob glob-regular-expr

Extract the global variable(s) matching global-regular-expr from the LLVM bitcode. All global variables matching the regular expression will be extracted. May be specified multiple times.

-help

Print a summary of command line options.

-o filename

Specify the output filename. If filename is "-" (the default), then :program:`llvm-extract` sends its output to standard output.

-S

Write output in LLVM intermediate language (instead of bitcode).

EXIT STATUS

If :program:`llvm-extract` succeeds, it will exit with 0. Otherwise, if an error occurs, it will exit with a non-zero value.

SEE ALSO

bugpoint