Implement a new type trait __is_trivially_constructible(T, Args...)

that provides the behavior of the C++11 library trait
std::is_trivially_constructible<T, Args...>, which can't be
implemented purely as a library.

Since __is_trivially_constructible can have zero or more arguments, I
needed to add Yet Another Type Trait Expression Class, this one
handling arbitrary arguments. The next step will be to migrate
UnaryTypeTrait and BinaryTypeTrait over to this new, more general
TypeTrait class.

Fixes the Clang side of <rdar://problem/10895483> / PR12038.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151352 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 47 insertions, 1 deletions

diff --git a/lib/AST/ExprCXX.cpp b/lib/AST/ExprCXX.cpp
index 7ef3417e6d..da89bf2798 100644
--- a/lib/AST/ExprCXX.cpp
+++ b/lib/AST/ExprCXX.cpp
@@ -199,7 +199,6 @@ SourceRange CXXPseudoDestructorExpr::getSourceRange() const {
   return SourceRange(Base->getLocStart(), End);
 }
 
-
 // UnresolvedLookupExpr
 UnresolvedLookupExpr *
 UnresolvedLookupExpr::Create(ASTContext &C, 
@@ -1262,4 +1261,51 @@ TemplateArgument SubstNonTypeTemplateParmPackExpr::getArgumentPack() const {
   return TemplateArgument(Arguments, NumArguments);
 }
 
+TypeTraitExpr::TypeTraitExpr(QualType T, SourceLocation Loc, TypeTrait Kind,
+                             ArrayRef<TypeSourceInfo *> Args,
+                             SourceLocation RParenLoc,
+                             bool Value)
+  : Expr(TypeTraitExprClass, T, VK_RValue, OK_Ordinary,
+         /*TypeDependent=*/false,
+         /*ValueDependent=*/false,
+         /*InstantiationDependent=*/false,
+         /*ContainsUnexpandedParameterPack=*/false),
+    Loc(Loc), RParenLoc(RParenLoc)
+{
+  TypeTraitExprBits.Kind = Kind;
+  TypeTraitExprBits.Value = Value;
+  TypeTraitExprBits.NumArgs = Args.size();
+
+  TypeSourceInfo **ToArgs = getTypeSourceInfos();
+  
+  for (unsigned I = 0, N = Args.size(); I != N; ++I) {
+    if (Args[I]->getType()->isDependentType())
+      setValueDependent(true);
+    if (Args[I]->getType()->isInstantiationDependentType())
+      setInstantiationDependent(true);
+    if (Args[I]->getType()->containsUnexpandedParameterPack())
+      setContainsUnexpandedParameterPack(true);
+    
+    ToArgs[I] = Args[I];
+  }
+}
+
+TypeTraitExpr *TypeTraitExpr::Create(ASTContext &C, QualType T, 
+                                     SourceLocation Loc, 
+                                     TypeTrait Kind,
+                                     ArrayRef<TypeSourceInfo *> Args,
+                                     SourceLocation RParenLoc,
+                                     bool Value) {
+  unsigned Size = sizeof(TypeTraitExpr) + sizeof(TypeSourceInfo*) * Args.size();
+  void *Mem = C.Allocate(Size);
+  return new (Mem) TypeTraitExpr(T, Loc, Kind, Args, RParenLoc, Value);
+}
+
+TypeTraitExpr *TypeTraitExpr::CreateDeserialized(ASTContext &C,
+                                                 unsigned NumArgs) {
+  unsigned Size = sizeof(TypeTraitExpr) + sizeof(TypeSourceInfo*) * NumArgs;
+  void *Mem = C.Allocate(Size);
+  return new (Mem) TypeTraitExpr(EmptyShell());
+}
+
 void ArrayTypeTraitExpr::anchor() { }