Auxiliary tools

A walking tour of the smaller binaries under tools/. Each is a thin CLI over a corresponding library in lib/.

Demangling

| Tool | Library | Use | | ------------------------- | ----------------- | ----------------------------------------- | ------------------------------------------- | | swift-demangle | lib/Demangling/ | echo $sBaaa | swift-demangle -- decode a mangled symbol. | | swift-demangle-fuzzer | same | LibFuzzer harness for the demangler. | | swift-demangle-yamldump | same | Print the demangler's parse tree as YAML. |

The compiler's mangling spec is docs/ABI/Mangling.rst. Two copies of the demangler exist: lib/Demangling/ (compiler-side) and the runtime copy in stdlib/public/Demangling/.

IDE and refactoring

Tool	Library	Use
swift-ide-test	lib/IDE/	CLI for completion, cursor info, conforming-method-list, semantic tokens.
swift-refactor	lib/Refactoring/	Run a single refactoring transformation (extract function, rename, etc.).

swift-ide-test is the workhorse for test/IDE/. Most completion test files have a // RUN: %target-swift-ide-test ... invocation.

Reflection and runtime inspection

Tool	Library	Use
swift-reflection-dump	lib/SwiftRemoteMirror/	Dump reflection metadata (__swift5_* sections) from a binary or .swiftmodule.
swift-reflection-fuzzer	same	LibFuzzer harness for the reflection reader.
swift-inspect	same	Inspect a running Swift process: list classes, count instances, dump heap.
swift-remoteast-test	lib/RemoteAST/	Test the RemoteAST library used by LLDB.

SwiftRemoteMirror is the C library that walks a remote process's metadata. Xcode's "Debug Memory Graph" and equivalent tools use it.

Macros

Tool	Library	Use
swift-plugin-server	lib/Macros/	Out-of-process host for user-defined Swift macros.
libMockPlugin	lib/Macros/	Mock plugin used by the macros test infrastructure.

Macros are loaded as compiler plugins; for trust and isolation, they execute in a separate process.

Module / API tools

Tool	Library	Use
swift-stdlib-tool	-	Apple-platform helper to bundle stdlib dylibs.
swift-compatibility-symbols	-	Reports the back-compat symbols emitted by an stdlib build.
swift-def-to-strings-converter	lib/Localization/	Convert DiagnosticsXxx.def to .strings for translation.
swift-serialize-diagnostics	-	Encode diagnostics into the .dia format consumed by Xcode.
swift-function-caller-generator	-	Generate thunks for cross-language function calls.
swift-scan-test	lib/DependencyScan/	Drive the dependency-scan library.

Debug-info / LLDB integration

Tool	Library	Use
lldb-moduleimport-test	lib/Frontend/	Test the LLDB-private importer entry point.
libStaticMirror	lib/StaticMirror/	Static reflection reader used by symbolgraph and tools.

Where to find a tool's tests

Each tool has a corresponding directory under test/ (e.g., test/Demangle/, test/IDE/, test/refactoring/, test/SymbolGraph/, test/SwiftDemangle/). The test files use // RUN: %target-<tool> substitutions defined in test/lit.cfg.

Related pages

• Driver and frontend -- the main swift binary.
• SourceKit -- the IDE service.
• Runtime -- demangler and reflection metadata producers.