[clang] [RFC] Initial implementation of P2719 (PR #113510)

[Oliver Hunt via cfe-commits]

================
@@ -3096,6 +3096,29 @@ bool Type::isStdByteType() const {
   return false;
 }
 
+TemplateDecl *Type::getSpecializedTemplateDecl() const {
+  const auto *DesugaredType = getUnqualifiedDesugaredType();
+  if (auto *Specialization = DesugaredType->getAs<TemplateSpecializationType>())
+    return Specialization->getTemplateName().getAsTemplateDecl();
+  if (const auto *Record = DesugaredType->getAsCXXRecordDecl()) {
+    if (auto *CTS = dyn_cast<ClassTemplateSpecializationDecl>(Record))
----------------
ojhunt wrote:

This helper is gone :D

https://github.com/llvm/llvm-project/pull/113510