[pypy-svn] r11989 - in pypy/dist/pypy: objspace/flow translator

[arigo at codespeak.net]

Author: arigo
Date: Thu May  5 23:52:09 2005
New Revision: 11989

Modified:
   pypy/dist/pypy/objspace/flow/framestate.py
   pypy/dist/pypy/objspace/flow/model.py
   pypy/dist/pypy/translator/annrpython.py
   pypy/dist/pypy/translator/gencl.py
   pypy/dist/pypy/translator/genpyrex.py
Log:
Make sure that undefined local variables can never propagate in flow graphs.


Modified: pypy/dist/pypy/objspace/flow/framestate.py
==============================================================================
--- pypy/dist/pypy/objspace/flow/framestate.py	(original)
+++ pypy/dist/pypy/objspace/flow/framestate.py	Thu May  5 23:52:09 2005
@@ -8,13 +8,8 @@
 
     def __init__(self, state):
         if isinstance(state, PyFrame):
-            data = []
-            for w in state.getfastscope():
-                if w is None:
-                    data.append(Constant(undefined_value))
-                else:
-                    data.append(w)
-            data.extend(state.valuestack.items)
+            # getfastscope() can return real None, for undefined locals
+            data = state.getfastscope() + state.valuestack.items
             if state.last_exception is None:
                 data.append(Constant(None))
                 data.append(Constant(None))
@@ -35,7 +30,7 @@
                             state.__class__.__name__)
         self.next_instr = self.nonmergeable[1]
         for w1 in self.mergeable:
-            assert isinstance(w1, (Variable, Constant)), (
+            assert isinstance(w1, (Variable, Constant)) or w1 is None, (
                 '%r found in frame state' % w1)
 
     def restoreframe(self, frame):
@@ -43,13 +38,7 @@
             fastlocals = len(frame.fastlocals_w)
             data = self.mergeable[:]
             recursively_unflatten(frame.space, data)
-            fastscope = []
-            for w in data[:fastlocals]:
-                if isinstance(w, Constant) and w.value is undefined_value:
-                    fastscope.append(None)
-                else:
-                    fastscope.append(w)
-            frame.setfastscope(fastscope)
+            frame.setfastscope(data[:fastlocals])  # Nones == undefined locals
             frame.valuestack.items[:] = data[fastlocals:-2]
             if data[-2] == Constant(None):
                 assert data[-1] == Constant(None)
@@ -121,6 +110,9 @@
 
 def union(w1, w2):
     "Union of two variables or constants."
+    if w1 is None or w2 is None:
+        return None  # if w1 or w2 is an undefined local, we "kill" the value
+                     # coming from the other path and return an undefined local
     if isinstance(w1, Variable) or isinstance(w2, Variable):
         return Variable()  # new fresh Variable
     if isinstance(w1, Constant) and isinstance(w2, Constant):

Modified: pypy/dist/pypy/objspace/flow/model.py
==============================================================================
--- pypy/dist/pypy/objspace/flow/model.py	(original)
+++ pypy/dist/pypy/objspace/flow/model.py	Thu May  5 23:52:09 2005
@@ -218,7 +218,6 @@
         return self.name
 last_exception = Atom('last_exception')
 last_exc_value = Atom('last_exc_value')
-undefined_value= Atom('*undefined*')
 # if Block().exitswitch == Constant(last_exception), it means that we are
 # interested in catching the exception that the *last operation* of the
 # block could raise.  The exitcases of the links are None for no exception

Modified: pypy/dist/pypy/translator/annrpython.py
==============================================================================
--- pypy/dist/pypy/translator/annrpython.py	(original)
+++ pypy/dist/pypy/translator/annrpython.py	Thu May  5 23:52:09 2005
@@ -5,7 +5,7 @@
 from pypy.annotation import model as annmodel
 from pypy.annotation.model import pair
 from pypy.annotation.bookkeeper import Bookkeeper
-from pypy.objspace.flow.model import Variable, Constant, undefined_value
+from pypy.objspace.flow.model import Variable, Constant
 from pypy.objspace.flow.model import SpaceOperation, FunctionGraph
 from pypy.objspace.flow.model import last_exception, last_exc_value
 
@@ -172,8 +172,8 @@
                 else:
                     raise
         elif isinstance(arg, Constant):
-            if arg.value is undefined_value:   # undefined local variables
-                return annmodel.SomeImpossibleValue()
+            #if arg.value is undefined_value:   # undefined local variables
+            #    return annmodel.SomeImpossibleValue()
             assert not arg.value is last_exception and not arg.value is last_exc_value
             return self.bookkeeper.immutablevalue(arg.value)
         else:

Modified: pypy/dist/pypy/translator/gencl.py
==============================================================================
--- pypy/dist/pypy/translator/gencl.py	(original)
+++ pypy/dist/pypy/translator/gencl.py	Thu May  5 23:52:09 2005
@@ -306,7 +306,7 @@
         target = link.target.inputargs
         print "(psetq", # parallel assignment
         for s, t in zip(source, target):
-            if s != t and s != Constant(undefined_value):
+            if s != t:  # and s != Constant(undefined_value):
                 print self.str(t), self.str(s),
         print ")"
         self.emit_jump(link.target)

Modified: pypy/dist/pypy/translator/genpyrex.py
==============================================================================
--- pypy/dist/pypy/translator/genpyrex.py	(original)
+++ pypy/dist/pypy/translator/genpyrex.py	Thu May  5 23:52:09 2005
@@ -4,7 +4,7 @@
 """
 from pypy.interpreter.baseobjspace import ObjSpace
 from pypy.interpreter.argument import Arguments
-from pypy.objspace.flow.model import Variable, Constant, undefined_value
+from pypy.objspace.flow.model import Variable, Constant
 from pypy.objspace.flow.model import mkentrymap, last_exception
 from pypy.translator.annrpython import RPythonAnnotator
 from pypy.annotation.model import SomePBC
@@ -407,7 +407,7 @@
         # get rid of identity-assignments and assignments of undefined_value
         sargs, targs = [], []
         for s,t in zip(sourceargs, targetargs):
-            if s != t and s != Constant(undefined_value):
+            if s != t:   # and s != Constant(undefined_value):
                 sargs.append(s)
                 targs.append(t)
         if sargs: