Make InstantiatingTemplate depth checks clearer

The bool conversion operator on InstantiatingTemplate never added value and
only served to obfuscate the template instantiation routines.

This replaces the conversion and its callers with an explicit isInvalid()
function to make it clear what's going on at a glance.

llvm-svn: 192177

6 files changed, 24 insertions, 25 deletions

diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index ed0e9cc4764..a70e609aeda 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -6221,7 +6221,7 @@ public:
 
     /// \brief Determines whether we have exceeded the maximum
     /// recursive template instantiations.
-    LLVM_EXPLICIT operator bool() const { return Invalid; }
+    bool isInvalid() const { return Invalid; }
 
   private:
     Sema &SemaRef;
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 12e6a260ac9..db231e55d61 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -3852,7 +3852,7 @@ ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
 
     InstantiatingTemplate Inst(*this, CallLoc, Param,
                                MutiLevelArgList.getInnermost());
-    if (Inst)
+    if (Inst.isInvalid())
       return ExprError();
 
     ExprResult Result;
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 79f6fb8f34a..09c2cf4fe82 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -2001,7 +2001,7 @@ QualType Sema::CheckTemplateIdType(TemplateName Name,
 
     LocalInstantiationScope Scope(*this);
     InstantiatingTemplate Inst(*this, TemplateLoc, Template);
-    if (Inst)
+    if (Inst.isInvalid())
       return QualType();
 
     CanonType = SubstType(Pattern->getUnderlyingType(),
@@ -2380,7 +2380,7 @@ DeclResult Sema::ActOnVarTemplateSpecialization(
     TemplateArgumentList TemplateArgList(TemplateArgumentList::OnStack,
                                          Converted.data(), Converted.size());
     InstantiatingTemplate Inst(*this, TemplateKWLoc, VarTemplate);
-    if (Inst)
+    if (Inst.isInvalid())
       return true;
     VarDecl *Templated = VarTemplate->getTemplatedDecl();
     ExpectedDI =
@@ -3061,7 +3061,7 @@ SubstDefaultTemplateArgument(Sema &SemaRef,
     Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
                                      Template, Converted,
                                      SourceRange(TemplateLoc, RAngleLoc));
-    if (Inst)
+    if (Inst.isInvalid())
       return 0;
 
     TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
@@ -3114,7 +3114,7 @@ SubstDefaultTemplateArgument(Sema &SemaRef,
   Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc,
                                    Template, Converted,
                                    SourceRange(TemplateLoc, RAngleLoc));
-  if (Inst)
+  if (Inst.isInvalid())
     return ExprError();
 
   TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
@@ -3166,7 +3166,7 @@ SubstDefaultTemplateArgument(Sema &SemaRef,
                              NestedNameSpecifierLoc &QualifierLoc) {
   Sema::InstantiatingTemplate Inst(SemaRef, TemplateLoc, Template, Converted,
                                    SourceRange(TemplateLoc, RAngleLoc));
-  if (Inst)
+  if (Inst.isInvalid())
     return TemplateName();
 
   TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
@@ -3317,7 +3317,7 @@ bool Sema::CheckTemplateArgument(NamedDecl *Param,
       InstantiatingTemplate Inst(*this, TemplateLoc, Template,
                                  NTTP, Converted,
                                  SourceRange(TemplateLoc, RAngleLoc));
-      if (Inst)
+      if (Inst.isInvalid())
         return true;
 
       TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
@@ -3452,7 +3452,7 @@ bool Sema::CheckTemplateArgument(NamedDecl *Param,
     InstantiatingTemplate Inst(*this, TemplateLoc, Template,
                                TempParm, Converted,
                                SourceRange(TemplateLoc, RAngleLoc));
-    if (Inst)
+    if (Inst.isInvalid())
       return true;
 
     TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack,
@@ -3763,10 +3763,9 @@ bool Sema::CheckTemplateArgumentList(TemplateDecl *Template,
 
     // Introduce an instantiation record that describes where we are using
     // the default template argument.
-    InstantiatingTemplate Instantiating(*this, RAngleLoc, Template,
-                                        *Param, Converted,
-                                        SourceRange(TemplateLoc, RAngleLoc));
-    if (Instantiating)
+    InstantiatingTemplate Inst(*this, RAngleLoc, Template, *Param, Converted,
+                               SourceRange(TemplateLoc, RAngleLoc));
+    if (Inst.isInvalid())
       return true;
 
     // Check the default template argument.
diff --git a/clang/lib/Sema/SemaTemplateDeduction.cpp b/clang/lib/Sema/SemaTemplateDeduction.cpp
index 4a2f939e2a6..8c239afc03c 100644
--- a/clang/lib/Sema/SemaTemplateDeduction.cpp
+++ b/clang/lib/Sema/SemaTemplateDeduction.cpp
@@ -2276,7 +2276,7 @@ Sema::DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial,
   SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
   InstantiatingTemplate Inst(*this, Partial->getLocation(), Partial,
                              DeducedArgs, Info);
-  if (Inst)
+  if (Inst.isInvalid())
     return TDK_InstantiationDepth;
 
   if (Trap.hasErrorOccurred())
@@ -2440,7 +2440,7 @@ Sema::DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial,
   SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
   InstantiatingTemplate Inst(*this, Partial->getLocation(), Partial,
                              DeducedArgs, Info);
-  if (Inst)
+  if (Inst.isInvalid())
     return TDK_InstantiationDepth;
 
   if (Trap.hasErrorOccurred())
@@ -2528,7 +2528,7 @@ Sema::SubstituteExplicitTemplateArguments(
                              FunctionTemplate, DeducedArgs,
            ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution,
                              Info);
-  if (Inst)
+  if (Inst.isInvalid())
     return TDK_InstantiationDepth;
 
   if (CheckTemplateArgumentList(FunctionTemplate,
@@ -2779,7 +2779,7 @@ Sema::FinishTemplateArgumentDeduction(FunctionTemplateDecl *FunctionTemplate,
                              FunctionTemplate, DeducedArgs,
               ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution,
                              Info);
-  if (Inst)
+  if (Inst.isInvalid())
     return TDK_InstantiationDepth;
 
   ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl());
diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index 32111bac3a4..f13b14bd0f1 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -1979,7 +1979,7 @@ Sema::InstantiateClass(SourceLocation PointOfInstantiation,
   }
   
   InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
-  if (Inst)
+  if (Inst.isInvalid())
     return true;
 
   // Enter the scope of this instantiation. We don't use
@@ -2216,7 +2216,7 @@ bool Sema::InstantiateEnum(SourceLocation PointOfInstantiation,
   }
 
   InstantiatingTemplate Inst(*this, PointOfInstantiation, Instantiation);
-  if (Inst)
+  if (Inst.isInvalid())
     return true;
 
   // Enter the scope of this instantiation. We don't use
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 35f3616db6a..c6f98bb3c1c 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -1554,7 +1554,7 @@ TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D,
                "inheriting constructor template in dependent context?");
         Sema::InstantiatingTemplate Inst(SemaRef, Constructor->getLocation(),
                                          Inh);
-        if (Inst)
+        if (Inst.isInvalid())
           return 0;
         Sema::ContextRAII SavedContext(SemaRef, Inh->getDeclContext());
         LocalInstantiationScope LocalScope(SemaRef);
@@ -2964,7 +2964,7 @@ void Sema::InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
 
   InstantiatingTemplate Inst(*this, PointOfInstantiation, Decl,
                              InstantiatingTemplate::ExceptionSpecification());
-  if (Inst) {
+  if (Inst.isInvalid()) {
     // We hit the instantiation depth limit. Clear the exception specification
     // so that our callers don't have to cope with EST_Uninstantiated.
     FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
@@ -3188,7 +3188,7 @@ void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
     Function->setImplicitlyInline();
 
   InstantiatingTemplate Inst(*this, PointOfInstantiation, Function);
-  if (Inst)
+  if (Inst.isInvalid())
     return;
 
   // Copy the inner loc start from the pattern.
@@ -3299,7 +3299,7 @@ VarTemplateSpecializationDecl *Sema::BuildVarTemplateInstantiation(
     return 0;
 
   InstantiatingTemplate Inst(*this, PointOfInstantiation, FromVar);
-  if (Inst)
+  if (Inst.isInvalid())
     return 0;
 
   MultiLevelTemplateArgumentList TemplateArgLists;
@@ -3569,7 +3569,7 @@ void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
       // FIXME: Factor out the duplicated instantiation context setup/tear down
       // code here.
       InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
-      if (Inst)
+      if (Inst.isInvalid())
         return;
 
       // If we're performing recursive template instantiation, create our own
@@ -3693,7 +3693,7 @@ void Sema::InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
   }
 
   InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
-  if (Inst)
+  if (Inst.isInvalid())
     return;
 
   // If we're performing recursive template instantiation, create our own