Cleanup and fixes

git-svn-id: http://llvm-py.googlecode.com/svn/trunk@68 8d1e9007-1d4e-0410-b67e-1979fd6579aa

llvm/__init__.py

@@ -32,7 +32,9 @@
 
 """
 
-VERSION = '0.3'
+VERSION = '0.6'
+
+from weakref import WeakValueDictionary
 
 
 #===----------------------------------------------------------------------===
@@ -78,3 +80,70 @@ class Ownable(object):
         if not self.owner:
             self.del_fn(self.ptr)
 
+
+#===----------------------------------------------------------------------===
+# Dummy owner, will not delete ownee. Be careful.
+#===----------------------------------------------------------------------===
+
+class DummyOwner(object):
+    pass
+
+
+#===----------------------------------------------------------------------===
+# A metaclass to prevent aliasing.  It stores a (weak) reference to objects
+# constructed based on a PyCObject.  If an object is constructed based on a
+# PyCObject with the same underlying pointer as a previous object, a reference
+# to the previous object is returned rather than a new one.
+#===----------------------------------------------------------------------===
+
+class _ObjectCache(type):
+    """A metaclass to prevent aliasing.
+
+    Classes using 'ObjectCache' as a metaclass must have constructors
+    that take a PyCObject as their first argument.  When the class is
+    called (to create a new instance of the class), the value of the
+    pointer wrapped by the PyCObj is checked:
+
+        If no previous object has been created based on the same
+        underlying pointer (note that different PyCObject objects can
+        wrap the same pointer), the object will be initialized as
+        usual and returned.
+
+        If a previous has been created based on the same pointer,
+        then a reference to that object will be returned, and no
+        object initialization is performed.
+    """
+
+    __instances = WeakValueDictionary()
+
+    def __call__(cls, ptr, *args, **kwargs):
+        objid = _core.PyCObjectVoidPtrToPyLong(ptr)
+        obj = _ObjectCache.__instances.get(objid)
+        if obj is None:
+            obj = super(_ObjectCache, cls).__call__(ptr, *args, **kwargs)
+            _ObjectCache.__instances[objid] = obj
+        return obj
+
+    @staticmethod
+    def forget(obj):
+        objid = _core.PyCObjectVoidPtrToPyLong(obj.ptr)
+        if objid in _ObjectCache.__instances:
+            del _ObjectCache.__instances[objid]
+
+
+#===----------------------------------------------------------------------===
+# Cacheables
+#===----------------------------------------------------------------------===
+
+class Cacheable(object):
+    """Objects that can be cached.
+
+    Objects that wrap a PyCObject are cached to avoid "aliasing", i.e.,
+    two Python objects each containing a PyCObject which internally points
+    to the same C pointer."""
+
+    __metaclass__ = _ObjectCache
+
+    def forget(self):
+        _ObjectCache.forget(self)
+

llvm/_util.py

@@ -34,7 +34,6 @@ Used only in other modules, not for public use."""
 
 import llvm
 import llvm._core as _core  # for PyCObjectVoidPtrToPyLong
-from weakref import WeakValueDictionary
 
 
 #===----------------------------------------------------------------------===
@@ -42,10 +41,10 @@ from weakref import WeakValueDictionary
 # failures.
 #===----------------------------------------------------------------------===
 
-def check_gen(obj, type):
+def check_gen(obj, typ):
-    if not isinstance(obj, type):
+    if not isinstance(obj, typ):
-        type_str = type.__name__
+        typ_str = typ.__name__
-        msg = "argument not an instance of llvm.core.%s" % type_str
+        msg = "argument not an instance of llvm.core.%s" % typ_str
         raise TypeError, msg
 
 def check_is_unowned(ownable):
@@ -70,51 +69,11 @@ def unpack_gen(objlist, check_fn):
 # we now return a list.
 #===----------------------------------------------------------------------===
 
-def wrapiter(first, next, container, wrapper, extra=[]):
+def wrapiter(first, next, container, wrapper):
-#    ptr = first(container)
-#    while ptr:
-#        yield wrapper(ptr)
-#        ptr = next(ptr)
     ret = []
     ptr = first(container)
     while ptr:
-        ret.append(wrapper(ptr, *extra))
+        ret.append(wrapper(ptr))
         ptr = next(ptr)
     return ret
 
-
-#===----------------------------------------------------------------------===
-# A metaclass to prevent aliasing.  It stores a (weak) reference to objects
-# constructed based on a PyCObject.  If an object is constructed based on a
-# PyCObject with the same underlying pointer as a previous object, a reference
-# to the previous object is returned rather than a new one.
-#===----------------------------------------------------------------------===
-
-class ObjectCache(type):
-    """A metaclass to prevent aliasing.
-
-    Classes using 'ObjectCache' as a metaclass must have constructors
-    that take a PyCObject as their first argument.  When the class is
-    called (to create a new instance of the class), the value of the
-    pointer wrapped by the PyCObj is checked:
-
-        If no previous object has been created based on the same
-        underlying pointer (note that different PyCObject objects can
-        wrap the same pointer), the object will be initialized as
-        usual and returned.
-
-        If a previous has been created based on the same pointer,
-        then a reference to that object will be returned, and no
-        object initialization is performed.
-    """
-
-    __instances = WeakValueDictionary()
-
-    def __call__(cls, ptr, *args, **kwargs):
-        id = _core.PyCObjectVoidPtrToPyLong(ptr)
-        obj = ObjectCache.__instances.get(id)
-        if obj is None:
-            obj = super(ObjectCache, cls).__call__(ptr, *args, **kwargs)
-            ObjectCache.__instances[id] = obj
-        return obj
-

llvm/core.py

@@ -37,7 +37,6 @@ in-memory intermediate representation (IR) data structures."""
 import llvm                 # top-level, for common stuff
 import llvm._core as _core  # C wrappers
 import llvm._util as _util  # utility functions
-import weakref              # global list of modules
 
 
 #===----------------------------------------------------------------------===
@@ -272,7 +271,7 @@ def _to_int(v):
 # Module
 #===----------------------------------------------------------------------===
 
-class Module(llvm.Ownable):
+class Module(llvm.Ownable, llvm.Cacheable):
     """A Module instance stores all the information related to an LLVM module.
 
     Modules are the top level container of all other LLVM Intermediate
@@ -287,8 +286,6 @@ class Module(llvm.Ownable):
     module_obj = Module.new('my_module')
     """
 
-    __metaclass__ = _util.ObjectCache
-
     @staticmethod
     def new(id):
         """Create a new Module instance.
@@ -392,12 +389,18 @@ class Module(llvm.Ownable):
         global variables, function, etc. are matched and resolved.
 
         The `other' module is no longer valid after this method is
-        invoked, and will behave in undefined ways.
+        invoked, all refs to it should be dropped.
+
+        In future, this API might be replaced with a full-fledged
+        Linker class.
         """
         check_is_module(other)
+        other.forget() # remove it from object cache
         ret = _core.LLVMLinkModules(self.ptr, other.ptr)
         if isinstance(ret, str):
             raise llvm.LLVMException, ret
+        # Do not try to destroy the other module's llvm::Module*.
+        other._own(llvm.DummyOwner())
 
     def add_type_name(self, name, ty):
         """Map a string to a type.
@@ -848,9 +851,7 @@ class TypeHandle(object):
 # Values
 #===----------------------------------------------------------------------===
 
-class Value(object):
+class Value(llvm.Cacheable):
-
-    __metaclass__ = _util.ObjectCache
 
     def __init__(self, ptr):
         self.ptr = ptr
@@ -1233,6 +1234,7 @@ class GlobalVariable(GlobalValue):
     def delete(self):
         self._delete()
         _core.LLVMDeleteGlobal(self.ptr)
+        self.forget()
         self.ptr = None
 
     def _get_initializer(self):
@@ -1310,6 +1312,7 @@ class Function(GlobalValue):
     def delete(self):
         self._delete()
         _core.LLVMDeleteFunction(self.ptr)
+        self.forget()
         self.ptr = None
 
     @property
@@ -1498,6 +1501,7 @@ class BasicBlock(Value):
 
     def delete(self):
         _core.LLVMDeleteBasicBlock(self.ptr)
+        self.forget()
         self.ptr = None
 
     @property

test/objcache.py

@@ -8,6 +8,12 @@ def check(a, b):
     else:
         print "FAIL"
 
+def check_isnot(a, b):
+    if not (a is b):
+        print "OK"
+    else:
+        print "FAIL"
+
 print "Testing module aliasing ..",
 m1 = Module.new('a')
 t = Type.int()
@@ -19,11 +25,18 @@ check(m1, m2)
 print "Testing global vairable aliasing 1 .. ",
 gv1 = GlobalVariable.new(m1, t, "gv")
 gv2 = GlobalVariable.get(m1, "gv")
-check(gv2, gv2)
+check(gv1, gv2)
 
 print "Testing global vairable aliasing 2 .. ",
 gv3 = m1.global_variables[0]
-check(gv3, gv1)
+check(gv1, gv3)
+
+print "Testing global vairable aliasing 3 .. ",
+gv2 = None
+gv3 = None
+gv1.delete()
+gv4 = GlobalVariable.new(m1, t, "gv")
+check_isnot(gv1, gv4)
 
 print "Testing function aliasing 1 ..",
 b1 = f1.append_basic_block('entry')