When substituting previously-checked template arguments into a template
template parameter that is an expanded parameter pack, only substitute into the
current slice, not the entire pack.
This reduces the checking of N template template arguments for an expanded
parameter pack containing N parameters from quadratic time to linear time in
the length of the pack. This is important because one (and possibly the only?)
general technique for splitting a template parameter pack in linear time
depends on doing this.
llvm-svn: 326973
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 800956d..6720435 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -3118,6 +3118,13 @@
return InstL;
}
+TemplateParameterList *
+Sema::SubstTemplateParams(TemplateParameterList *Params, DeclContext *Owner,
+ const MultiLevelTemplateArgumentList &TemplateArgs) {
+ TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
+ return Instantiator.SubstTemplateParams(Params);
+}
+
/// \brief Instantiate the declaration of a class template partial
/// specialization.
///