[DWARF] Force a linkage_name on an inlined subprogram's abstract origin.

When we suppress linkage names, for a non-inlined subprogram the name
can still be found in the object-file symbol table, because we have
the code address of the subprogram.  This is not necessarily the case
for an inlined subprogram, so we still want to emit the linkage name
in the DWARF.  Put this on the abstract-origin DIE because it's common
to all inlined instances.

Differential Revision: http://reviews.llvm.org/D18706

llvm-svn: 266692

1 files changed, 19 insertions, 11 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 36b87657ae7..373b7e7daa3 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -105,13 +105,21 @@ DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
                             clEnumVal(Disable, "Disabled"), clEnumValEnd),
                  cl::init(Default));
 
-static cl::opt<DefaultOnOff>
-DwarfLinkageNames("dwarf-linkage-names", cl::Hidden,
-                  cl::desc("Emit DWARF linkage-name attributes."),
-                  cl::values(clEnumVal(Default, "Default for platform"),
-                             clEnumVal(Enable, "Enabled"),
-                             clEnumVal(Disable, "Disabled"), clEnumValEnd),
-                  cl::init(Default));
+enum LinkageNameOption {
+  DefaultLinkageNames,
+  AllLinkageNames,
+  AbstractLinkageNames
+};
+static cl::opt<LinkageNameOption>
+    DwarfLinkageNames("dwarf-linkage-names", cl::Hidden,
+                      cl::desc("Which DWARF linkage-name attributes to emit."),
+                      cl::values(clEnumValN(DefaultLinkageNames, "Default",
+                                            "Default for platform"),
+                                 clEnumValN(AllLinkageNames, "All", "All"),
+                                 clEnumValN(AbstractLinkageNames, "Abstract",
+                                            "Abstract subprograms"),
+                                 clEnumValEnd),
+                      cl::init(DefaultLinkageNames));
 
 static const char *const DWARFGroupName = "DWARF Emission";
 static const char *const DbgTimerName = "DWARF Debug Writer";
@@ -245,11 +253,11 @@ DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
   else
     HasDwarfPubSections = DwarfPubSections == Enable;
 
-  // SCE does not use linkage names.
-  if (DwarfLinkageNames == Default)
-    UseLinkageNames = !tuneForSCE();
+  // SCE defaults to linkage names only for abstract subprograms.
+  if (DwarfLinkageNames == DefaultLinkageNames)
+    UseAllLinkageNames = !tuneForSCE();
   else
-    UseLinkageNames = DwarfLinkageNames == Enable;
+    UseAllLinkageNames = DwarfLinkageNames == AllLinkageNames;
 
   unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion;
   DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber