[pypy-svn] pypy default: have the llbackend raise on ValueError on bad shift counts

[hakanardo]

Author: Hakan Ardo <hakan at debian.org>
Branch: 
Changeset: r43567:4c695a1b8a86
Date: 2011-04-25 12:21 +0200
http://bitbucket.org/pypy/pypy/changeset/4c695a1b8a86/

Log:	have the llbackend raise on ValueError on bad shift counts

diff --git a/pypy/jit/metainterp/blackhole.py b/pypy/jit/metainterp/blackhole.py
--- a/pypy/jit/metainterp/blackhole.py
+++ b/pypy/jit/metainterp/blackhole.py
@@ -238,6 +238,10 @@
         interp.cleanup_registers()
         self.blackholeinterps.append(interp)
 
+def check_shift_count(b):
+    if not we_are_translated():
+        if b < 0 or b >= LONG_BIT:
+            raise ValueError("Shift count, %d,  not in valid range, 0 .. %d." % (b, LONG_BIT-1))
 
 class BlackholeInterpreter(object):
 
@@ -420,14 +424,17 @@
 
     @arguments("i", "i", returns="i")
     def bhimpl_int_rshift(a, b):
+        check_shift_count(b)
         return a >> b
 
     @arguments("i", "i", returns="i")
     def bhimpl_int_lshift(a, b):
+        check_shift_count(b)
         return intmask(a << b)
 
     @arguments("i", "i", returns="i")
     def bhimpl_uint_rshift(a, b):
+        check_shift_count(b)
         c = r_uint(a) >> r_uint(b)
         return intmask(c)
 

diff --git a/pypy/jit/metainterp/test/test_blackhole.py b/pypy/jit/metainterp/test/test_blackhole.py
--- a/pypy/jit/metainterp/test/test_blackhole.py
+++ b/pypy/jit/metainterp/test/test_blackhole.py
@@ -217,3 +217,16 @@
                            for x in range(1, 8)])
         builder = pyjitpl._warmrunnerdesc.metainterp_sd.blackholeinterpbuilder
         assert builder.num_interpreters == 2
+
+def test_bad_shift():
+    py.test.raises(ValueError, BlackholeInterpreter.bhimpl_int_lshift.im_func, 7, 100)
+    py.test.raises(ValueError, BlackholeInterpreter.bhimpl_int_rshift.im_func, 7, 100)
+    py.test.raises(ValueError, BlackholeInterpreter.bhimpl_uint_rshift.im_func, 7, 100)
+    py.test.raises(ValueError, BlackholeInterpreter.bhimpl_int_lshift.im_func, 7, -1)
+    py.test.raises(ValueError, BlackholeInterpreter.bhimpl_int_rshift.im_func, 7, -1)
+    py.test.raises(ValueError, BlackholeInterpreter.bhimpl_uint_rshift.im_func, 7, -1)
+
+    assert BlackholeInterpreter.bhimpl_int_lshift.im_func(100, 3) == 100<<3
+    assert BlackholeInterpreter.bhimpl_int_rshift.im_func(100, 3) == 100>>3
+    assert BlackholeInterpreter.bhimpl_uint_rshift.im_func(100, 3) == 100>>3        
+