c++filt: support COFF import thunks

The synthetic thunk for the import is prefixed with __imp_.  Attempt to
undecorate the names when they begin with the __imp_ prefix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298550 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/tools/llvm-cxxfilt/llvm-cxxfilt.cpp b/tools/llvm-cxxfilt/llvm-cxxfilt.cpp
index 8be2a6d3b45..13024fbeaea 100644
--- a/tools/llvm-cxxfilt/llvm-cxxfilt.cpp
+++ b/tools/llvm-cxxfilt/llvm-cxxfilt.cpp
@@ -68,6 +68,12 @@ static void demangle(llvm::raw_ostream &OS, const std::string &Mangled) {
                 (DecoratedLength >= 4 && strncmp(Decorated, "___Z", 4) == 0)))
     Undecorated = itaniumDemangle(Decorated, nullptr, nullptr, &Status);
 
+  if (!Undecorated &&
+      (DecoratedLength > 6 && strncmp(Decorated, "__imp_", 6) == 0)) {
+    OS << "import thunk for ";
+    Undecorated = itaniumDemangle(Decorated + 6, nullptr, nullptr, &Status);
+  }
+
   OS << (Undecorated ? Undecorated : Mangled) << '\n';
 
   free(Undecorated);