LLVM-EXTRACT(1)

✨ NAME ✨

llvm-extract — extract a function from an LLVM module 🎀 (yes bestie, that's the whole vibe: one function, plucked out, iconic)

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🌸 SYNOPSIS 🌸

llvm-extract [options] --func function-name [filename]

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💅 DESCRIPTION 💅

okay so llvm-extract is that girl. you hand her the name of a function, and she extracts it from the LLVM bitcode file you point her at. she's mostly a debugging tool — her whole main character job is shrinking big messy test cases down from giant programs that are out here triggering a bug 🐛🔪

and it's not just the function, bestie. alongside pulling out the bitcode of the function you asked for, llvm-extract also clears out the unreachable global variables, the prototypes, and the unused types. decluttering queen ✨

where does she read from? standard input if you skip filename, or if filename is literally -. and where does she write? always standard output — always, no discussion — unless you pass the -o option (more on her below 👇).

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🦋 OPTIONS 🦋

• --alias alias-name — extract the alias named function-name from the LLVM bitcode. (ngl the man page really does say function-name right there in the alias section — iykyk, we're keeping it fr fr 💀) you can pass this more than once to extract multiple alias at once.
• --ralias alias-regular-expr — extract the alias matching alias-regular-expr from the LLVM bitcode. every alias matching that regular expression gets extracted. may be specified multiple times.
• --bb basic-block-specifier — extract basic blocks(s) specicified 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. periodt.
• -f — enable binary output on terminals. normally llvm-extract will refuse to write raw bitcode output if the output stream is a terminal (she has boundaries 🫶). with this option she'll 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. stack 'em up 🌈
• --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. don't touch them, they're fine 🙈
• --recursive — recursively extract all called functions. it's giving "and her friends, and their friends, and their friends…" 🧚
• -help — print a summary of command line options. a little menu, a little moment.
• -o filename — specify the output filename. if filename is - (which is the default), then llvm-extract sends its output to standard output.
• -S — write output in LLVM intermediate language (instead of bitcode). the readable version, slay 💅

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⭐ EXIT STATUS ⭐

if llvm-extract succeeds, she exits with 0 💖. otherwise, if an error occurs, she exits with a non-zero value. no in-between, no drama, just numbers.

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🔥 SEE ALSO 🔥

• bugpoint(1)

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👑 AUTHOR 👑

maintained by the LLVM Team (https://llvm.org/). they're the ones keeping this whole thing alive, fr fr.

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🌈 COPYRIGHT 🌈

2003-2024, LLVM Project

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and that's the whole page bestie 🫶 this was the LLVM man page for LLVM-EXTRACT(1), page 11, dated 2024-07-18 — go extract something iconic, ily, bye 💜✨