llvm-for-llvmta/docs/CommandGuide/llvm-extract.rst

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llvm-extract - extract a function from an LLVM module
=====================================================
.. program:: llvm-extract
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
-------
**--alias** *alias-name*
Extract the alias named *function-name* from the LLVM bitcode. May be
specified multiple times to extract multiple alias at once.
**--ralias** *alias-regular-expr*
Extract the alias matching *alias-regular-expr* from the LLVM bitcode.
All alias matching the regular expression will be extracted. May be
specified multiple times.
**--bb** *basic-block-specifier*
Extract basic blocks(s) specified in *basic-block-specifier*. May be
specified multiple times. Each <function:bb[;bb]> specifier pair will create
a function. If multiple basic blocks are specified in one pair, the first
block in the sequence should dominate the rest.
**--delete**
Delete specified Globals from Module.
**-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.
**--keep-const-init**
Preserve the values of constant globals.
**--recursive**
Recursively extract all called functions
**-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
--------
:manpage:`bugpoint(1)`