MFC r265477: Merge -fstandalone-debug from Clang r198655:

  Implement a new -fstandalone-debug option. rdar://problem/15685848
  It controls everything that -flimit-debug-info used to, plus the
  vtable type optimization. The old -fno-limit-debug-info option is now an
  alias to -fstandalone-debug and vice versa.

  Standalone is the default on Darwin until dtrace is updated to work with
  non-standalone debug info (rdar://problem/15758808).

  Note: I kept the LimitedDebugInfo name in CodeGenOptions::DebugInfoKind
  because NoStandaloneDebugInfo sounded even more confusing.

2 files changed, 20 insertions, 10 deletions

diff --git a/contrib/llvm/tools/clang/include/clang/Driver/Options.td b/contrib/llvm/tools/clang/include/clang/Driver/Options.td
index ccfdf74..5e7c76d 100644
--- a/contrib/llvm/tools/clang/include/clang/Driver/Options.td
+++ b/contrib/llvm/tools/clang/include/clang/Driver/Options.td
@@ -549,8 +549,6 @@ def finstrument_functions : Flag<["-"], "finstrument-functions">, Group<f_Group>
 def fkeep_inline_functions : Flag<["-"], "fkeep-inline-functions">, Group<clang_ignored_f_Group>;
 def flat__namespace : Flag<["-"], "flat_namespace">;
 def flax_vector_conversions : Flag<["-"], "flax-vector-conversions">, Group<f_Group>;
-def flimit_debug_info : Flag<["-"], "flimit-debug-info">, Group<f_Group>, Flags<[CC1Option]>,
-  HelpText<"Limit debug information produced to reduce size of debug binary">;
 def flimited_precision_EQ : Joined<["-"], "flimited-precision=">, Group<f_Group>;
 def flto : Flag<["-"], "flto">, Group<f_Group>;
 def fno_lto : Flag<["-"], "fno-lto">, Group<f_Group>;
@@ -645,8 +643,6 @@ def fno_inline : Flag<["-"], "fno-inline">, Group<f_clang_Group>, Flags<[CC1Opti
 def fno_keep_inline_functions : Flag<["-"], "fno-keep-inline-functions">, Group<clang_ignored_f_Group>;
 def fno_lax_vector_conversions : Flag<["-"], "fno-lax-vector-conversions">, Group<f_Group>,
   HelpText<"Disallow implicit conversions between vectors with a different number of elements or different element types">, Flags<[CC1Option]>;
-def fno_limit_debug_info : Flag<["-"], "fno-limit-debug-info">, Group<f_Group>, Flags<[CC1Option]>,
-  HelpText<"Do not limit debug information produced to reduce size of debug binary">;
 def fno_merge_all_constants : Flag<["-"], "fno-merge-all-constants">, Group<f_Group>,
     Flags<[CC1Option]>, HelpText<"Disallow merging of constants">;
 def fno_modules : Flag <["-"], "fno-modules">, Group<f_Group>,
@@ -774,6 +770,12 @@ def fno_signed_char : Flag<["-"], "fno-signed-char">, Flags<[CC1Option]>,
 def fsplit_stack : Flag<["-"], "fsplit-stack">, Group<f_Group>;
 def fstack_protector_all : Flag<["-"], "fstack-protector-all">, Group<f_Group>;
 def fstack_protector : Flag<["-"], "fstack-protector">, Group<f_Group>;
+def fstandalone_debug : Flag<["-"], "fstandalone-debug">, Group<f_Group>, Flags<[CC1Option]>,
+  HelpText<"Emit full debug info for all types used by the program">;
+def fno_standalone_debug : Flag<["-"], "fno-standalone-debug">, Group<f_Group>, Flags<[CC1Option]>,
+  HelpText<"Limit debug information produced to reduce size of debug binary">;
+def flimit_debug_info : Flag<["-"], "flimit-debug-info">, Alias<fno_standalone_debug>;
+def fno_limit_debug_info : Flag<["-"], "fno-limit-debug-info">, Alias<fstandalone_debug>;
 def fstrict_aliasing : Flag<["-"], "fstrict-aliasing">, Group<f_Group>;
 def fstrict_enums : Flag<["-"], "fstrict-enums">, Group<f_Group>, Flags<[CC1Option]>,
   HelpText<"Enable optimizations based on the strict definition of an enum's "
diff --git a/contrib/llvm/tools/clang/include/clang/Frontend/CodeGenOptions.h b/contrib/llvm/tools/clang/include/clang/Frontend/CodeGenOptions.h
index 86aabf7..0d24697 100644
--- a/contrib/llvm/tools/clang/include/clang/Frontend/CodeGenOptions.h
+++ b/contrib/llvm/tools/clang/include/clang/Frontend/CodeGenOptions.h
@@ -50,12 +50,20 @@ public:
   };
 
   enum DebugInfoKind {
-    NoDebugInfo,          // Don't generate debug info.
-    DebugLineTablesOnly,  // Emit only debug info necessary for generating
-                          // line number tables (-gline-tables-only).
-    LimitedDebugInfo,     // Limit generated debug info to reduce size
-                          // (-flimit-debug-info).
-    FullDebugInfo         // Generate complete debug info.
+    NoDebugInfo,          /// Don't generate debug info.
+
+    DebugLineTablesOnly,  /// Emit only debug info necessary for generating
+                          /// line number tables (-gline-tables-only).
+
+    LimitedDebugInfo,     /// Limit generated debug info to reduce size
+                          /// (-fno-standalone-debug). This emits
+                          /// forward decls for types that could be
+                          /// replaced with forward decls in the source
+                          /// code. For dynamic C++ classes type info
+                          /// is only emitted int the module that
+                          /// contains the classe's vtable.
+
+    FullDebugInfo         /// Generate complete debug info.
   };
 
   enum TLSModel {