[pypy-commit] pypy stmgc-c4: Fix?

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: stmgc-c4
Changeset: r66844:6db8370436ba
Date: 2013-09-07 20:06 +0200
http://bitbucket.org/pypy/pypy/changeset/6db8370436ba/

Log:	Fix?

diff --git a/rpython/translator/stm/writebarrier.py b/rpython/translator/stm/writebarrier.py
--- a/rpython/translator/stm/writebarrier.py
+++ b/rpython/translator/stm/writebarrier.py
@@ -134,7 +134,7 @@
         def get_category_or_null(v):
             # 'v' is an original variable here, or a constant
             if isinstance(v, Constant) and not v.value:    # a NULL constant
-                return None
+                return 'Z'
             if v in renamings:
                 return renamings[v].category
             if isinstance(v, Constant):
@@ -205,7 +205,7 @@
             if op in self.expand_comparison:
                 cats = (get_category_or_null(op.args[0]),
                         get_category_or_null(op.args[1]))
-                if None not in cats and (cats[0] < 'V' or cats[1] < 'V'):
+                if 'Z' not in cats and (cats[0] < 'V' or cats[1] < 'V'):
                     if newop.opname == 'ptr_ne':
                         v = varoftype(lltype.Bool)
                         negop = SpaceOperation('bool_not', [v],
@@ -346,6 +346,7 @@
            * 'R': the read barrier was applied
            * 'V': same as W, except needs a repeat_write_barrier
            * 'W': the write barrier was applied
+           * 'Z': the null constant
 
        The letters are chosen so that a barrier is needed to change a
        pointer from category x to category y if and only if y > x.