Use LLVM's new ItaniumPartialDemangler in LLDB
Summary:
Replace the existing combination of FastDemangle and the fallback to llvm::itaniumDemangle() with LLVM's new ItaniumPartialDemangler. It slightly reduces complexity and slightly improves performance, but doesn't introduce conceptual changes. This patch is preparing for more fundamental improvements on LLDB's demangling approach.
Reviewers: friss, jingham, erik.pilkington, labath, clayborg, mgorny, davide, JDevlieghere
Reviewed By: JDevlieghere
Subscribers: teemperor, JDevlieghere, labath, clayborg, davide, lldb-commits, mgorny, erik.pilkington
Differential Revision: https://reviews.llvm.org/D49612
llvm-svn: 337931
diff --git a/lldb/source/Core/Mangled.cpp b/lldb/source/Core/Mangled.cpp
index 3f64a3d..545ac51 100644
--- a/lldb/source/Core/Mangled.cpp
+++ b/lldb/source/Core/Mangled.cpp
@@ -16,34 +16,24 @@
#pragma comment(lib, "dbghelp.lib")
#endif
-#ifdef LLDB_USE_BUILTIN_DEMANGLER
-// Provide a fast-path demangler implemented in FastDemangle.cpp until it can
-// replace the existing C++ demangler with a complete implementation
-#include "lldb/Utility/FastDemangle.h"
-#include "llvm/Demangle/Demangle.h"
-#else
-// FreeBSD9-STABLE requires this to know about size_t in cxxabi.
-#include <cstddef>
-#include <cxxabi.h>
-#endif
-
#include "lldb/Utility/ConstString.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/Logging.h"
#include "lldb/Utility/RegularExpression.h"
#include "lldb/Utility/Stream.h"
#include "lldb/Utility/Timer.h"
-#include "lldb/lldb-enumerations.h" // for LanguageType
+#include "lldb/lldb-enumerations.h"
#include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
#include "Plugins/Language/ObjC/ObjCLanguage.h"
-#include "llvm/ADT/StringRef.h" // for StringRef
-#include "llvm/Support/Compiler.h" // for LLVM_PRETT...
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Demangle/Demangle.h"
+#include "llvm/Support/Compiler.h"
-#include <mutex> // for mutex, loc...
-#include <string> // for string
-#include <utility> // for pair
+#include <mutex>
+#include <string>
+#include <utility>
#include <stdlib.h>
#include <string.h>
@@ -295,18 +285,15 @@
break;
}
case eManglingSchemeItanium: {
-#ifdef LLDB_USE_BUILTIN_DEMANGLER
- if (log)
- log->Printf("demangle itanium: %s", mangled_name);
- // 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 =
- llvm::itaniumDemangle(mangled_name, NULL, NULL, NULL);
-#else
- demangled_name = abi::__cxa_demangle(mangled_name, NULL, NULL, NULL);
-#endif
+ llvm::ItaniumPartialDemangler IPD;
+ bool demangle_err = IPD.partialDemangle(mangled_name);
+ if (!demangle_err) {
+ // Default buffer and size (realloc is used in case it's too small).
+ size_t demangled_size = 80;
+ demangled_name = static_cast<char *>(::malloc(demangled_size));
+ demangled_name = IPD.finishDemangle(demangled_name, &demangled_size);
+ }
+
if (log) {
if (demangled_name)
log->Printf("demangled itanium: %s -> \"%s\"", mangled_name,