1 files changed, 148 insertions, 0 deletions
diff --git a/llvm/tools/llvm-cxxfilt/llvm-cxxfilt.cpp b/llvm/tools/llvm-cxxfilt/llvm-cxxfilt.cpp
new file mode 100644
index 000000000000..9ac8bcf0ff01
--- /dev/null
+++ b/llvm/tools/llvm-cxxfilt/llvm-cxxfilt.cpp
@@ -0,0 +1,148 @@
+//===-- llvm-c++filt.cpp --------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Demangle/Demangle.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cstdlib>
+#include <iostream>
+
+using namespace llvm;
+
+enum Style {
+  Auto,  ///< auto-detect mangling
+  GNU,   ///< GNU
+  Lucid, ///< Lucid compiler (lcc)
+  ARM,
+  HP,    ///< HP compiler (xCC)
+  EDG,   ///< EDG compiler
+  GNUv3, ///< GNU C++ v3 ABI
+  Java,  ///< Java (gcj)
+  GNAT   ///< ADA compiler (gnat)
+};
+static cl::opt<Style>
+    Format("format", cl::desc("decoration style"),
+           cl::values(clEnumValN(Auto, "auto", "auto-detect style"),
+                      clEnumValN(GNU, "gnu", "GNU (itanium) style")),
+           cl::init(Auto));
+static cl::alias FormatShort("s", cl::desc("alias for --format"),
+                             cl::aliasopt(Format));
+
+static cl::opt<bool> StripUnderscore("strip-underscore",
+                                     cl::desc("strip the leading underscore"),
+                                     cl::init(false));
+static cl::alias StripUnderscoreShort("_",
+                                      cl::desc("alias for --strip-underscore"),
+                                      cl::aliasopt(StripUnderscore));
+
+static cl::opt<bool>
+    Types("types",
+          cl::desc("attempt to demangle types as well as function names"),
+          cl::init(false));
+static cl::alias TypesShort("t", cl::desc("alias for --types"),
+                            cl::aliasopt(Types));
+
+static cl::list<std::string>
+Decorated(cl::Positional, cl::desc("<mangled>"), cl::ZeroOrMore);
+
+static cl::extrahelp
+    HelpResponse("\nPass @FILE as argument to read options from FILE.\n");
+
+static std::string demangle(llvm::raw_ostream &OS, const std::string &Mangled) {
+  int Status;
+
+  const char *DecoratedStr = Mangled.c_str();
+  if (StripUnderscore)
+    if (DecoratedStr[0] == '_')
+      ++DecoratedStr;
+  size_t DecoratedLength = strlen(DecoratedStr);
+
+  char *Undecorated = nullptr;
+
+  if (Types ||
+      ((DecoratedLength >= 2 && strncmp(DecoratedStr, "_Z", 2) == 0) ||
+       (DecoratedLength >= 4 && strncmp(DecoratedStr, "___Z", 4) == 0)))
+    Undecorated = itaniumDemangle(DecoratedStr, nullptr, nullptr, &Status);
+
+  if (!Undecorated &&
+      (DecoratedLength > 6 && strncmp(DecoratedStr, "__imp_", 6) == 0)) {
+    OS << "import thunk for ";
+    Undecorated = itaniumDemangle(DecoratedStr + 6, nullptr, nullptr, &Status);
+  }
+
+  std::string Result(Undecorated ? Undecorated : Mangled);
+  free(Undecorated);
+  return Result;
+}
+
+// Split 'Source' on any character that fails to pass 'IsLegalChar'.  The
+// returned vector consists of pairs where 'first' is the delimited word, and
+// 'second' are the delimiters following that word.
+static void SplitStringDelims(
+    StringRef Source,
+    SmallVectorImpl<std::pair<StringRef, StringRef>> &OutFragments,
+    function_ref<bool(char)> IsLegalChar) {
+  // The beginning of the input string.
+  const auto Head = Source.begin();
+
+  // Obtain any leading delimiters.
+  auto Start = std::find_if(Head, Source.end(), IsLegalChar);
+  if (Start != Head)
+    OutFragments.push_back({"", Source.slice(0, Start - Head)});
+
+  // Capture each word and the delimiters following that word.
+  while (Start != Source.end()) {
+    Start = std::find_if(Start, Source.end(), IsLegalChar);
+    auto End = std::find_if_not(Start, Source.end(), IsLegalChar);
+    auto DEnd = std::find_if(End, Source.end(), IsLegalChar);
+    OutFragments.push_back({Source.slice(Start - Head, End - Head),
+                            Source.slice(End - Head, DEnd - Head)});
+    Start = DEnd;
+  }
+}
+
+// This returns true if 'C' is a character that can show up in an
+// Itanium-mangled string.
+static bool IsLegalItaniumChar(char C) {
+  // Itanium CXX ABI [External Names]p5.1.1:
+  // '$' and '.' in mangled names are reserved for private implementations.
+  return isalnum(C) || C == '.' || C == '$' || C == '_';
+}
+
+// If 'Split' is true, then 'Mangled' is broken into individual words and each
+// word is demangled.  Otherwise, the entire string is treated as a single
+// mangled item.  The result is output to 'OS'.
+static void demangleLine(llvm::raw_ostream &OS, StringRef Mangled, bool Split) {
+  std::string Result;
+  if (Split) {
+    SmallVector<std::pair<StringRef, StringRef>, 16> Words;
+    SplitStringDelims(Mangled, Words, IsLegalItaniumChar);
+    for (const auto &Word : Words)
+      Result += demangle(OS, Word.first) + Word.second.str();
+  } else
+    Result = demangle(OS, Mangled);
+  OS << Result << '\n';
+  OS.flush();
+}
+
+int main(int argc, char **argv) {
+  InitLLVM X(argc, argv);
+
+  cl::ParseCommandLineOptions(argc, argv, "llvm symbol undecoration tool\n");
+
+  if (Decorated.empty())
+    for (std::string Mangled; std::getline(std::cin, Mangled);)
+      demangleLine(llvm::outs(), Mangled, true);
+  else
+    for (const auto &Symbol : Decorated)
+      demangleLine(llvm::outs(), Symbol, false);
+
+  return EXIT_SUCCESS;
+}