remerge fixes from rpython-never-allocate

5 files changed, 18 insertions, 12 deletions

diff --git a/pypy/doc/whatsnew-head.rst b/pypy/doc/whatsnew-head.rst
index 436630784e..b47b83778a 100644
--- a/pypy/doc/whatsnew-head.rst
+++ b/pypy/doc/whatsnew-head.rst
@@ -54,3 +54,9 @@ Backport fixes to winreg adding reflection and fix for passing None (bpo
 
 Change parameter type of ``PyModule_New`` to ``const char*``, add
 ``PyModule_Check`` and ``PyModule_CheckExact``
+
+.. branch: rpython-never-allocate
+
+Introduce a ``@never_allocate`` class decorator, which ensure that a certain
+RPython class is never actually instantiated at runtime. Useful to ensure that
+e.g. it's always constant-folded away
diff --git a/rpython/rtyper/lltypesystem/ll2ctypes.py b/rpython/rtyper/lltypesystem/ll2ctypes.py
index d9fdd322d7..efa6f11a2f 100644
--- a/rpython/rtyper/lltypesystem/ll2ctypes.py
+++ b/rpython/rtyper/lltypesystem/ll2ctypes.py
@@ -374,9 +374,9 @@ def build_new_ctypes_type(T, delayed_builders):
     elif isinstance(T, lltype.OpaqueType):
         if T is lltype.RuntimeTypeInfo:
             return ctypes.c_char * 2
-        if T.hints.get('external', None) != 'C':
+        if T._hints.get('external', None) != 'C':
             raise TypeError("%s is not external" % T)
-        return ctypes.c_char * T.hints['getsize']()
+        return ctypes.c_char * T._hints['getsize']()
     else:
         _setup_ctypes_cache()
         if T in _ctypes_cache:
@@ -934,7 +934,7 @@ def lltype2ctypes(llobj, normalize=True):
                     convert_array(container)
                 elif isinstance(T.TO, lltype.OpaqueType):
                     if T.TO != lltype.RuntimeTypeInfo:
-                        cbuf = ctypes.create_string_buffer(T.TO.hints['getsize']())
+                        cbuf = ctypes.create_string_buffer(T.TO._hints['getsize']())
                     else:
                         cbuf = ctypes.create_string_buffer("\x00")
                     cbuf = ctypes.cast(cbuf, ctypes.c_void_p)
diff --git a/rpython/rtyper/lltypesystem/lltype.py b/rpython/rtyper/lltypesystem/lltype.py
index eaa51f1edc..c75fd90e7a 100644
--- a/rpython/rtyper/lltypesystem/lltype.py
+++ b/rpython/rtyper/lltypesystem/lltype.py
@@ -584,7 +584,7 @@ class OpaqueType(ContainerType):
         """
         self.tag = tag
         self.__name__ = tag
-        self.hints = frozendict(hints)
+        self._hints = frozendict(hints)
 
     def __str__(self):
         return "%s (opaque)" % self.tag
diff --git a/rpython/translator/c/database.py b/rpython/translator/c/database.py
index f21f661ba3..bf0ced6418 100644
--- a/rpython/translator/c/database.py
+++ b/rpython/translator/c/database.py
@@ -84,7 +84,7 @@ class LowLevelDatabase(object):
                     node = BareBoneArrayDefNode(self, T, varlength)
                 else:
                     node = ArrayDefNode(self, T, varlength)
-            elif isinstance(T, OpaqueType) and T.hints.get("render_structure", False):
+            elif isinstance(T, OpaqueType) and T._hints.get("render_structure", False):
                 node = ExtTypeOpaqueDefNode(self, T)
             elif T == WeakRef:
                 REALT = self.gcpolicy.get_real_weakref_type()
@@ -102,8 +102,8 @@ class LowLevelDatabase(object):
             return '%s @' % T.c_name
         elif isinstance(T, Ptr):
             if (isinstance(T.TO, OpaqueType) and
-                T.TO.hints.get('c_pointer_typedef') is not None):
-                return '%s @' % T.TO.hints['c_pointer_typedef']
+                T.TO._hints.get('c_pointer_typedef') is not None):
+                return '%s @' % T.TO._hints['c_pointer_typedef']
             try:
                 node = self.gettypedefnode(T.TO)
             except NoCorrespondingNode:
@@ -134,13 +134,13 @@ class LowLevelDatabase(object):
         elif isinstance(T, OpaqueType):
             if T == RuntimeTypeInfo:
                 return  self.gcpolicy.rtti_type()
-            elif T.hints.get("render_structure", False):
+            elif T._hints.get("render_structure", False):
                 node = self.gettypedefnode(T, varlength=varlength)
                 if who_asks is not None:
                     who_asks.dependencies.add(node)
                 return 'struct %s @' % node.name
-            elif T.hints.get('external', None) == 'C':
-                return '%s @' % T.hints['c_name']
+            elif T._hints.get('external', None) == 'C':
+                return '%s @' % T._hints['c_name']
             else:
                 #raise Exception("don't know about opaque type %r" % (T,))
                 return 'struct %s @' % (
@@ -182,7 +182,7 @@ class LowLevelDatabase(object):
             return PrimitiveName[T](obj, self)
         elif isinstance(T, Ptr):
             if (isinstance(T.TO, OpaqueType) and
-                T.TO.hints.get('c_pointer_typedef') is not None):
+                T.TO._hints.get('c_pointer_typedef') is not None):
                 if obj._obj is not None:
                     value = rffi.cast(rffi.SSIZE_T, obj)
                     return '((%s) %s)' % (cdecl(self.gettype(T), ''),
diff --git a/rpython/translator/c/node.py b/rpython/translator/c/node.py
index 91458b643c..7898be2bdb 100644
--- a/rpython/translator/c/node.py
+++ b/rpython/translator/c/node.py
@@ -947,7 +947,7 @@ class ExtType_OpaqueNode(ContainerNode):
 def opaquenode_factory(db, T, obj):
     if T == RuntimeTypeInfo:
         return db.gcpolicy.rtti_node_factory()(db, T, obj)
-    if T.hints.get("render_structure", False):
+    if T._hints.get("render_structure", False):
         return ExtType_OpaqueNode(db, T, obj)
     raise Exception("don't know about %r" % (T,))