diff options
Diffstat (limited to 'include/llvm/Support/Casting.h')
| -rw-r--r-- | include/llvm/Support/Casting.h | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/include/llvm/Support/Casting.h b/include/llvm/Support/Casting.h index d35febbe6d..0c71882a77 100644 --- a/include/llvm/Support/Casting.h +++ b/include/llvm/Support/Casting.h @@ -15,6 +15,7 @@ #ifndef LLVM_SUPPORT_CASTING_H #define LLVM_SUPPORT_CASTING_H +#include "llvm/Support/type_traits.h" #include <cassert> namespace llvm { @@ -44,13 +45,23 @@ template<typename From> struct simplify_type<const From> { // The core of the implementation of isa<X> is here; To and From should be // the names of classes. This template can be specialized to customize the // implementation of isa<> without rewriting it from scratch. -template <typename To, typename From> +template <typename To, typename From, typename Enabler = void> struct isa_impl { static inline bool doit(const From &Val) { return To::classof(&Val); } }; +/// \brief Always allow upcasts, and perform no dynamic check for them. +template <typename To, typename From> +struct isa_impl<To, From, + typename llvm::enable_if_c< + llvm::is_base_of<To, From>::value + >::type + > { + static inline bool doit(const From &) { return true; } +}; + template <typename To, typename From> struct isa_impl_cl { static inline bool doit(const From &Val) { return isa_impl<To, From>::doit(Val); |