PR9992: Serialize and deserialize the token sequence for a function template in

-fdelayed-template-parsing mode. Patch by Will Wilson!

llvm-svn: 187916

4 files changed, 35 insertions, 4 deletions

diff --git a/clang/lib/Sema/MultiplexExternalSemaSource.cpp b/clang/lib/Sema/MultiplexExternalSemaSource.cpp
index d85624ba6f6..de790e9a2d1 100644
--- a/clang/lib/Sema/MultiplexExternalSemaSource.cpp
+++ b/clang/lib/Sema/MultiplexExternalSemaSource.cpp
@@ -267,3 +267,9 @@ void MultiplexExternalSemaSource::ReadPendingInstantiations(
   for(size_t i = 0; i < Sources.size(); ++i)
     Sources[i]->ReadPendingInstantiations(Pending);
 }
+
+void MultiplexExternalSemaSource::ReadLateParsedTemplates(
+    llvm::DenseMap<const FunctionDecl *, LateParsedTemplate *> &LPTMap) {
+  for (size_t i = 0; i < Sources.size(); ++i)
+    Sources[i]->ReadLateParsedTemplates(LPTMap);
+}
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index b75ef9a5f88..873bfcd3f83 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -173,6 +173,10 @@ void Sema::Initialize() {
 }
 
 Sema::~Sema() {
+  for (LateParsedTemplateMapT::iterator I = LateParsedTemplateMap.begin(),
+                                        E = LateParsedTemplateMap.end();
+       I != E; ++I)
+    delete I->second;
   if (PackContext) FreePackedContext();
   if (VisContext) FreeVisContext();
   delete TheTargetAttributesSema;
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index be43495982a..50cca0d94ac 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -7902,11 +7902,26 @@ Sema::getTemplateArgumentBindingsText(const TemplateParameterList *Params,
   return Out.str();
 }
 
-void Sema::MarkAsLateParsedTemplate(FunctionDecl *FD, bool Flag) {
+void Sema::MarkAsLateParsedTemplate(FunctionDecl *FD, Decl *FnD,
+                                    CachedTokens &Toks) {
   if (!FD)
     return;
-  FD->setLateTemplateParsed(Flag);
-} 
+
+  LateParsedTemplate *LPT = new LateParsedTemplate;
+
+  // Take tokens to avoid allocations
+  LPT->Toks.swap(Toks);
+  LPT->D = FnD;
+  LateParsedTemplateMap[FD] = LPT;
+
+  FD->setLateTemplateParsed(true);
+}
+
+void Sema::UnmarkAsLateParsedTemplate(FunctionDecl *FD) {
+  if (!FD)
+    return;
+  FD->setLateTemplateParsed(false);
+}
 
 bool Sema::IsInsideALocalClassWithinATemplateFunction() {
   DeclContext *DC = CurContext;
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 0ca6611c358..5ba6be3929f 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -3112,7 +3112,13 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
   // a templated function definition.
   if (!Pattern && PatternDecl->isLateTemplateParsed() &&
       LateTemplateParser) {
-    LateTemplateParser(OpaqueParser, PatternDecl);
+    // FIXME: Optimize to allow individual templates to be deserialized.
+    if (PatternDecl->isFromASTFile())
+      ExternalSource->ReadLateParsedTemplates(LateParsedTemplateMap);
+
+    LateParsedTemplate *LPT = LateParsedTemplateMap.lookup(PatternDecl);
+    assert(LPT && "missing LateParsedTemplate");
+    LateTemplateParser(OpaqueParser, *LPT);
     Pattern = PatternDecl->getBody(PatternDecl);
   }