Revert "Allow both MSVC and Itanium mangling schemes."
Cause build break.

This reverts commit 6d986061393f2863fec739e04412281148acc1f3.

llvm-svn: 238496
diff --git a/lldb/source/Core/Mangled.cpp b/lldb/source/Core/Mangled.cpp
index d277db7..48d1182 100644
--- a/lldb/source/Core/Mangled.cpp
+++ b/lldb/source/Core/Mangled.cpp
@@ -13,7 +13,6 @@
 #if defined(_MSC_VER)
 #include "lldb/Host/windows/windows.h"
 #include <Dbghelp.h>
-#define LLDB_USE_BUILTIN_DEMANGLER
 #elif defined (__FreeBSD__)
 #define LLDB_USE_BUILTIN_DEMANGLER
 #else
@@ -45,23 +44,16 @@
 
 using namespace lldb_private;
 
-static inline Mangled::ManglingScheme
-cstring_mangling_scheme(const char *s)
+static inline bool
+cstring_is_mangled (const char *s)
 {
     if (s)
-    {
-        if (s[0] == '?')
-            return Mangled::eManglingSchemeMSVC;
-        if (s[0] == '_' && s[1] == 'Z')
-            return Mangled::eManglingSchemeItanium;
-    }
-    return Mangled::eManglingSchemeNone;
-}
-
-static inline bool
-cstring_is_mangled(const char *s)
-{
-    return cstring_mangling_scheme(s) != Mangled::eManglingSchemeNone;
+#if defined(_MSC_VER)
+        return (s[0] == '?');
+#else
+        return (s[0] == '_' && s[1] == 'Z');
+#endif
+    return false;
 }
 
 static const ConstString &
@@ -272,58 +264,45 @@
                             m_mangled.GetCString());
 
         // Don't bother running anything that isn't mangled
-        const char *mangled_name = m_mangled.GetCString();
-        ManglingScheme mangling_scheme{cstring_mangling_scheme(mangled_name)};
-        if (mangling_scheme != eManglingSchemeNone &&
-            !m_mangled.GetMangledCounterpart(m_demangled))
+        const char *mangled_cstr = m_mangled.GetCString();
+        if (cstring_is_mangled(mangled_cstr))
         {
-            // We didn't already mangle this name, demangle it and if all goes well
-            // add it to our map.
-            char *demangled_name = nullptr;
-            switch (mangling_scheme)
+            if (!m_mangled.GetMangledCounterpart(m_demangled))
             {
-                case eManglingSchemeMSVC:
-                {
-#if defined(_MSC_VER)
-                    const size_t demangled_length = 2048;
-                    demangled_name = static_cast<char *>(::malloc(demangled_length));
-                    ::ZeroMemory(demangled_name, demangled_length);
-                    DWORD result = ::UnDecorateSymbolName(mangled_name, demangled_name, demangled_length,
-                            UNDNAME_NO_ACCESS_SPECIFIERS   | // Strip public, private, protected keywords
-                            UNDNAME_NO_ALLOCATION_LANGUAGE | // Strip __thiscall, __stdcall, etc keywords
-                            UNDNAME_NO_THROW_SIGNATURES    | // Strip throw() specifications
-                            UNDNAME_NO_MEMBER_TYPE         | // Strip virtual, static, etc specifiers
-                            UNDNAME_NO_MS_KEYWORDS           // Strip all MS extension keywords
-                        );
-                    if (result == 0)
-                    {
-                        free(demangled_name);
-                        demangled_name = nullptr;
-                    }
-#endif
-                    break;
-                }
-                case eManglingSchemeItanium:
-                {
+                // We didn't already mangle this name, demangle it and if all goes well
+                // add it to our map.
 #ifdef LLDB_USE_BUILTIN_DEMANGLER
-                    // Try to use the fast-path demangler first for the
-                    // performance win, falling back to the full demangler only
-                    // when necessary
-                    demangled_name = FastDemangle(mangled_name, m_mangled.GetLength());
-                    if (!demangled_name)
-                        demangled_name = __cxa_demangle(mangled_name, NULL, NULL, NULL);
-#else
-                    demangled_name = abi::__cxa_demangle(mangled_name, NULL, NULL, NULL);
-#endif
-                    break;
+                // Try to use the fast-path demangler first for the
+                // performance win, falling back to the full demangler only
+                // when necessary
+                char *demangled_name = FastDemangle (mangled_cstr,
+                                                     m_mangled.GetLength());
+                if (!demangled_name)
+                    demangled_name = __cxa_demangle (mangled_cstr, NULL, NULL, NULL);
+#elif defined(_MSC_VER)
+                char *demangled_name = (char *)::malloc(1024);
+                ::ZeroMemory(demangled_name, 1024);
+                DWORD result = ::UnDecorateSymbolName(mangled_cstr, demangled_name, 1023,
+                                                      UNDNAME_NO_ACCESS_SPECIFIERS |       // Strip public, private, protected keywords
+                                                          UNDNAME_NO_ALLOCATION_LANGUAGE | // Strip __thiscall, __stdcall, etc keywords
+                                                          UNDNAME_NO_THROW_SIGNATURES |    // Strip throw() specifications
+                                                          UNDNAME_NO_MEMBER_TYPE |         // Strip virtual, static, etc specifiers
+                                                          UNDNAME_NO_MS_KEYWORDS           // Strip all MS extension keywords
+                                                      );
+                if (result == 0)
+                {
+                    free (demangled_name);
+                    demangled_name = nullptr;
                 }
-                case eManglingSchemeNone:
-                    break;
-            }
-            if (demangled_name)
-            {
-                m_demangled.SetCStringWithMangledCounterpart(demangled_name, m_mangled);
-                free(demangled_name);
+#else
+                char *demangled_name = abi::__cxa_demangle (mangled_cstr, NULL, NULL, NULL);
+#endif
+
+                if (demangled_name)
+                {
+                    m_demangled.SetCStringWithMangledCounterpart(demangled_name, m_mangled);
+                    free (demangled_name);
+                }
             }
         }
         if (!m_demangled)