LLVM-CXXMAP(1)

💅 NAME 💅

Okay bestie, welcome to LLVM-CXXMAP(1) — the manual page for llvm-cxxmap, hanging out under the big LLVM manual umbrella 💖. This is the mangled name remapping tool, and it’s here to help you match C++ mangled names with fuzzy energy, based on a file that says which name components should count as equivalent. No cap.

✨ SYNOPSIS ✨

llvm-cxxmap [options] symbol-file-1 symbol-file-2

🌸 DESCRIPTION 🌸

llvm-cxxmap does fuzzy matching of C++ mangled names, using a file that describes which name components should be considered equivalent. It’s giving matchmaker, but for symbols 💅.

Your symbol files should contain a list of C++ mangled names, one per line. Blank lines and lines starting with # are ignored — yes, you can leave little comments, we love that for you.

The output is a list of pairs of equivalent symbols, one per line, of the form:

<symbol-1> <symbol-2>

where <symbol-1> is a symbol from symbol-file-1 and <symbol-2> is a symbol from symbol-file-2. Mappings where the two symbols are identical are omitted — no duplicate-symbol clutter, periodt.

🎀 OPTIONS 🎀

• -remapping-file=file, -r=file — Specify a file containing a list of equivalence rules that should be used to determine whether two symbols are equivalent. Required. See REMAPPING FILE below. Like, you genuinely cannot skip this one.
• -output=file, -o=file — Specify a file to write the list of matched names to. If unspecified, the list will be written to stdout.
• -Wambiguous — Produce a warning if there are multiple equivalent (but distinct) symbols in symbol-file-2.
• -Wincomplete — Produce a warning if symbol-file-1 contains a symbol for which there is no equivalent symbol in symbol-file-2.

🦋 REMAPPING FILE 🦋

The remapping file is a text file containing lines of the form:

fragmentkind fragment1 fragment2

where fragmentkind is one of name, type, or encoding, indicating whether the following mangled name fragments are <name>s, <type>s, or <encoding>s, respectively. Blank lines and lines starting with # are ignored.

Unmangled C names can be expressed as an encoding that is a (length-prefixed) <source-name>:

# C function "void foo_bar()" is remapped to C++ function "void foo::bar()".
encoding 7foo_bar _Z3foo3barv

For convenience, built-in <substitution>s such as St and Ss are accepted as <name>s (even though they technically are not <name>s).

For example, to specify that absl::string_view and std::string_view should be treated as equivalent, the following remapping file could be used:

# absl::string_view is considered equivalent to std::string_view
type N4absl11string_viewE St17basic_string_viewIcSt11char_traitsIcEE

# std:: might be std::__1:: in libc++ or std::__cxx11:: in libstdc++
name St St3__1
name St St7__cxx11

NOTE: Symbol remapping is currently only supported for C++ mangled names following the Itanium C++ ABI mangling scheme. This covers all C++ targets supported by Clang other than Windows targets. That’s the vibe check for now 💀.

💖 AUTHOR 💖

Maintained by the LLVM Team (https://llvm.org/).

🌈 COPYRIGHT 🌈

2003-2023, LLVM Project

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Cute footer sign-off, because we’re not copying the footer line directly: source/version 17, date 2023-12-01, manual LLVM-CXXMAP(1) — mwah 💋✨