[DWARF] Allow forward declarations of a class template instantiation

to have child entries describing the template parameters.  This will
be on by default for SCE tuning.

Differential Revision: https://reviews.llvm.org/D14358

llvm-svn: 314444

3 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 5581d76c20c..a73e4a98b3c 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -833,6 +833,10 @@ CGDebugInfo::getOrCreateRecordFwdDecl(const RecordType *Ty,
   llvm::DICompositeType *RetTy = DBuilder.createReplaceableCompositeType(
       getTagForRecord(RD), RDName, Ctx, DefUnit, Line, 0, Size, Align,
       llvm::DINode::FlagFwdDecl, FullName);
+  if (CGM.getCodeGenOpts().DebugFwdTemplateParams)
+    if (auto *TSpecial = dyn_cast<ClassTemplateSpecializationDecl>(RD))
+      DBuilder.replaceArrays(RetTy, llvm::DINodeArray(),
+                             CollectCXXTemplateParams(TSpecial, DefUnit));
   ReplaceMap.emplace_back(
       std::piecewise_construct, std::make_tuple(Ty),
       std::make_tuple(static_cast<llvm::Metadata *>(RetTy)));
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 8cb598ad0bd..90d912511e9 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -2969,6 +2969,11 @@ static void RenderDebugOptions(const ToolChain &TC, const Driver &D,
     CmdArgs.push_back("-generate-type-units");
   }
 
+  // Decide how to render forward declarations of template instantiations.
+  // SCE wants full descriptions, others just get them in the name.
+  if (DebuggerTuning == llvm::DebuggerKind::SCE)
+    CmdArgs.push_back("-debug-forward-template-params");
+
   RenderDebugInfoCompressionArgs(Args, CmdArgs, D);
 }
 
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index c4e8976cf3a..e1b14d0c156 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -528,6 +528,7 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.SplitDwarfInlining = !Args.hasArg(OPT_fno_split_dwarf_inlining);
   Opts.DebugTypeExtRefs = Args.hasArg(OPT_dwarf_ext_refs);
   Opts.DebugExplicitImport = Triple.isPS4CPU();
+  Opts.DebugFwdTemplateParams = Args.hasArg(OPT_debug_forward_template_params);
 
   for (const auto &Arg : Args.getAllArgValues(OPT_fdebug_prefix_map_EQ))
     Opts.DebugPrefixMap.insert(StringRef(Arg).split('='));