[pypy-commit] pypy default: Put @elidable on calls to identityhash() only.

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r46050:88f51d44dcd9
Date: 2011-07-28 11:58 +0200
http://bitbucket.org/pypy/pypy/changeset/88f51d44dcd9/

Log:	Put @elidable on calls to identityhash() only.

diff --git a/pypy/jit/codewriter/support.py b/pypy/jit/codewriter/support.py
--- a/pypy/jit/codewriter/support.py
+++ b/pypy/jit/codewriter/support.py
@@ -20,6 +20,7 @@
 from pypy.rpython.annlowlevel import MixLevelHelperAnnotator
 from pypy.jit.metainterp.typesystem import deref
 from pypy.rlib import rgc
+from pypy.rlib.jit import elidable
 from pypy.rlib.rarithmetic import r_longlong, r_ulonglong, r_uint, intmask
 
 def getargtypes(annotator, values):
@@ -167,9 +168,14 @@
 
 _ll_5_list_ll_arraycopy = rgc.ll_arraycopy
 
+ at elidable
 def _ll_1_gc_identityhash(x):
     return lltype.identityhash(x)
 
+# the following function should not be "@elidable": I can think of
+# a corner case in which id(const) is constant-folded, and then 'const'
+# disappears and is collected too early (possibly causing another object
+# with the same id() to appear).
 def _ll_1_gc_id(ptr):
     return llop.gc_id(lltype.Signed, ptr)