Better scheme to lookup alternate mangled name when looking up function address.

Summary:
This change is relevant for inferiors compiled with GCC. GCC does not
emit complete debug info for std::basic_string<...>, and consequently, Clang
(the LLDB compiler) does not generate correct mangled names for certain
functions.

This change removes the hard-coded alternate names in
ItaniumABILanguageRuntime.cpp.

Before the hard-coded names were put in ItaniumABILanguageRuntime.cpp, one could
not evaluate std::string methods (ex. std::string::length). After putting in
the hard-coded names, one could evaluate them. However, it did not still
enable one to call methods on, say for example, std::vector<string>.
This change makes that possible.

There is some amount of incompleteness in this change. Consider the
following example:

std::string hello("hello"), world("world");
std::map<std::string, std::string> m;
m[hello] = world;

One can still not evaluate the expression "m[hello]" in LLDB. Will
address this issue in another pass.

Reviewers: jingham, vharron, evgeny777, spyffe, dawn

Subscribers: clayborg, dawn, lldb-commits

Differential Revision: http://reviews.llvm.org/D12809

llvm-svn: 257113

3 files changed, 27 insertions, 0 deletions

diff --git a/lldb/source/Symbol/ClangASTContext.cpp b/lldb/source/Symbol/ClangASTContext.cpp
index 8b11c239aab..a0834757443 100644
--- a/lldb/source/Symbol/ClangASTContext.cpp
+++ b/lldb/source/Symbol/ClangASTContext.cpp
@@ -9969,6 +9969,18 @@ ClangASTContext::DeclContextGetName (void *opaque_decl_ctx)
     return ConstString();
 }
 
+ConstString
+ClangASTContext::DeclContextGetScopeQualifiedName (void *opaque_decl_ctx)
+{
+    if (opaque_decl_ctx)
+    {
+        clang::NamedDecl *named_decl = llvm::dyn_cast<clang::NamedDecl>((clang::DeclContext *)opaque_decl_ctx);
+        if (named_decl)
+            return ConstString(llvm::StringRef(named_decl->getQualifiedNameAsString()));
+    }
+    return ConstString();
+}
+
 bool
 ClangASTContext::DeclContextIsClassMethod (void *opaque_decl_ctx,
                                            lldb::LanguageType *language_ptr,
diff --git a/lldb/source/Symbol/CompilerDeclContext.cpp b/lldb/source/Symbol/CompilerDeclContext.cpp
index e44cee67284..8bee1b48753 100644
--- a/lldb/source/Symbol/CompilerDeclContext.cpp
+++ b/lldb/source/Symbol/CompilerDeclContext.cpp
@@ -38,6 +38,15 @@ CompilerDeclContext::GetName () const
         return ConstString();
 }
 
+ConstString
+CompilerDeclContext::GetScopeQualifiedName () const
+{
+    if (IsValid())
+        return m_type_system->DeclContextGetScopeQualifiedName(m_opaque_decl_ctx);
+    else
+        return ConstString();
+}
+
 bool
 CompilerDeclContext::IsStructUnionOrClass () const
 {
diff --git a/lldb/source/Symbol/SymbolFile.cpp b/lldb/source/Symbol/SymbolFile.cpp
index 51e35048d5c..82bbceb9610 100644
--- a/lldb/source/Symbol/SymbolFile.cpp
+++ b/lldb/source/Symbol/SymbolFile.cpp
@@ -134,6 +134,12 @@ SymbolFile::FindFunctions (const RegularExpression& regex, bool include_inlines,
     return 0;
 }
 
+void
+SymbolFile::GetMangledNamesForFunction(const std::string &scope_qualified_name, std::vector<ConstString> &mangled_names)
+{
+    return;
+}
+
 uint32_t
 SymbolFile::FindTypes (const SymbolContext& sc, const ConstString &name, const CompilerDeclContext *parent_decl_ctx, bool append, uint32_t max_matches, TypeMap& types)
 {