c++: Implement __is_pointer built-in trait

This patch implements built-in trait for std::is_pointer.

gcc/cp/ChangeLog:

	* cp-trait.def: Define __is_pointer.
	* constraint.cc (diagnose_trait_expr): Handle CPTK_IS_POINTER.
	* semantics.cc (trait_expr_value): Likewise.
	(finish_trait_expr): Likewise.

gcc/testsuite/ChangeLog:

	* g++.dg/ext/has-builtin-1.C: Test existence of __is_pointer.
	Arrange the order lexically around __is_pointer.
	* g++.dg/ext/is_pointer.C: New test.

Signed-off-by: Ken Matsui <kmatsui@gcc.gnu.org>
Reviewed-by: Jason Merrill <jason@redhat.com>

5 files changed, 65 insertions, 3 deletions

diff --git a/gcc/cp/constraint.cc b/gcc/cp/constraint.cc
index d9caf54..5a8aaa7 100644
--- a/gcc/cp/constraint.cc
+++ b/gcc/cp/constraint.cc
@@ -3829,6 +3829,9 @@ diagnose_trait_expr (tree expr, tree args)
     case CPTK_IS_POD:
       inform (loc, "  %qT is not a POD type", t1);
       break;
+    case CPTK_IS_POINTER:
+      inform (loc, "  %qT is not a pointer", t1);
+      break;
     case CPTK_IS_POLYMORPHIC:
       inform (loc, "  %qT is not a polymorphic type", t1);
       break;
diff --git a/gcc/cp/cp-trait.def b/gcc/cp/cp-trait.def
index e934745..18e2d0f 100644
--- a/gcc/cp/cp-trait.def
+++ b/gcc/cp/cp-trait.def
@@ -82,6 +82,7 @@ DEFTRAIT_EXPR (IS_NOTHROW_CONVERTIBLE, "__is_nothrow_convertible", 2)
 DEFTRAIT_EXPR (IS_OBJECT, "__is_object", 1)
 DEFTRAIT_EXPR (IS_POINTER_INTERCONVERTIBLE_BASE_OF, "__is_pointer_interconvertible_base_of", 2)
 DEFTRAIT_EXPR (IS_POD, "__is_pod", 1)
+DEFTRAIT_EXPR (IS_POINTER, "__is_pointer", 1)
 DEFTRAIT_EXPR (IS_POLYMORPHIC, "__is_polymorphic", 1)
 DEFTRAIT_EXPR (IS_REFERENCE, "__is_reference", 1)
 DEFTRAIT_EXPR (IS_SAME, "__is_same", 2)
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 634a324..b8c2bf8 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -12588,6 +12588,9 @@ trait_expr_value (cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_POD:
       return pod_type_p (type1);
 
+    case CPTK_IS_POINTER:
+      return TYPE_PTR_P (type1);
+
     case CPTK_IS_POLYMORPHIC:
       return CLASS_TYPE_P (type1) && TYPE_POLYMORPHIC_P (type1);
 
@@ -12827,6 +12830,7 @@ finish_trait_expr (location_t loc, cp_trait_kind kind, tree type1, tree type2)
     case CPTK_IS_MEMBER_OBJECT_POINTER:
     case CPTK_IS_MEMBER_POINTER:
     case CPTK_IS_OBJECT:
+    case CPTK_IS_POINTER:
     case CPTK_IS_REFERENCE:
     case CPTK_IS_SAME:
     case CPTK_IS_SCOPED_ENUM:
diff --git a/gcc/testsuite/g++.dg/ext/has-builtin-1.C b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
index b2e2f2f..4cbe6fe 100644
--- a/gcc/testsuite/g++.dg/ext/has-builtin-1.C
+++ b/gcc/testsuite/g++.dg/ext/has-builtin-1.C
@@ -119,12 +119,15 @@
 #if !__has_builtin (__is_object)
 # error "__has_builtin (__is_object) failed"
 #endif
-#if !__has_builtin (__is_pointer_interconvertible_base_of)
-# error "__has_builtin (__is_pointer_interconvertible_base_of) failed"
-#endif
 #if !__has_builtin (__is_pod)
 # error "__has_builtin (__is_pod) failed"
 #endif
+#if !__has_builtin (__is_pointer)
+# error "__has_builtin (__is_pointer) failed"
+#endif
+#if !__has_builtin (__is_pointer_interconvertible_base_of)
+# error "__has_builtin (__is_pointer_interconvertible_base_of) failed"
+#endif
 #if !__has_builtin (__is_polymorphic)
 # error "__has_builtin (__is_polymorphic) failed"
 #endif
diff --git a/gcc/testsuite/g++.dg/ext/is_pointer.C b/gcc/testsuite/g++.dg/ext/is_pointer.C
new file mode 100644
index 0000000..d6e3956
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/is_pointer.C
@@ -0,0 +1,51 @@
+// { dg-do compile { target c++11 } }
+
+#define SA(X) static_assert((X),#X)
+
+SA(!__is_pointer(int));
+SA(__is_pointer(int*));
+SA(__is_pointer(int**));
+
+SA(__is_pointer(const int*));
+SA(__is_pointer(const int**));
+SA(__is_pointer(int* const));
+SA(__is_pointer(int** const));
+SA(__is_pointer(int* const* const));
+
+SA(__is_pointer(volatile int*));
+SA(__is_pointer(volatile int**));
+SA(__is_pointer(int* volatile));
+SA(__is_pointer(int** volatile));
+SA(__is_pointer(int* volatile* volatile));
+
+SA(__is_pointer(const volatile int*));
+SA(__is_pointer(const volatile int**));
+SA(__is_pointer(const int* volatile));
+SA(__is_pointer(volatile int* const));
+SA(__is_pointer(int* const volatile));
+SA(__is_pointer(const int** volatile));
+SA(__is_pointer(volatile int** const));
+SA(__is_pointer(int** const volatile));
+SA(__is_pointer(int* const* const volatile));
+SA(__is_pointer(int* volatile* const volatile));
+SA(__is_pointer(int* const volatile* const volatile));
+
+SA(!__is_pointer(int&));
+SA(!__is_pointer(const int&));
+SA(!__is_pointer(volatile int&));
+SA(!__is_pointer(const volatile int&));
+
+SA(!__is_pointer(int&&));
+SA(!__is_pointer(const int&&));
+SA(!__is_pointer(volatile int&&));
+SA(!__is_pointer(const volatile int&&));
+
+SA(!__is_pointer(int[3]));
+SA(!__is_pointer(const int[3]));
+SA(!__is_pointer(volatile int[3]));
+SA(!__is_pointer(const volatile int[3]));
+
+SA(!__is_pointer(int(int)));
+SA(__is_pointer(int(*const)(int)));
+SA(__is_pointer(int(*volatile)(int)));
+SA(__is_pointer(int(*const volatile)(int)));