[pypy-svn] pypy default: Add some decorators about some constructor functions

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: 
Changeset: r43379:bfa61b4d5577
Date: 2011-04-15 10:34 +0200
http://bitbucket.org/pypy/pypy/changeset/bfa61b4d5577/

Log:	Add some decorators about some constructor functions being pure. It
	should avoid seeing in the jit traces lines like
	call(ConstClass(fromint), 1).

diff --git a/pypy/rlib/rbigint.py b/pypy/rlib/rbigint.py
--- a/pypy/rlib/rbigint.py
+++ b/pypy/rlib/rbigint.py
@@ -3,7 +3,8 @@
 from pypy.rlib.rarithmetic import most_neg_value_of_same_type
 from pypy.rlib.rfloat import isinf, isnan
 from pypy.rlib.debug import make_sure_not_resized, check_regular_int
-from pypy.rlib.objectmodel import we_are_translated
+from pypy.rlib.objectmodel import we_are_translated, specialize
+from pypy.rlib import jit
 from pypy.rpython.lltypesystem import lltype, rffi
 from pypy.rpython import extregistry
 
@@ -122,7 +123,11 @@
     def numdigits(self):
         return len(self._digits)
 
+    @staticmethod
+    @jit.purefunction
     def fromint(intval):
+        # This function is marked as pure, so you must not call it and
+        # then modify the result.
         check_regular_int(intval)
         if intval < 0:
             sign = -1
@@ -149,20 +154,25 @@
             t >>= SHIFT
             p += 1
         return v
-    fromint = staticmethod(fromint)
 
+    @staticmethod
+    @jit.purefunction
     def frombool(b):
+        # This function is marked as pure, so you must not call it and
+        # then modify the result.
         if b:
             return rbigint([ONEDIGIT], 1)
         return rbigint()
-    frombool = staticmethod(frombool)
 
+    @staticmethod
     def fromlong(l):
+        "NOT_RPYTHON"
         return rbigint(*args_from_long(l))
-    fromlong = staticmethod(fromlong)
 
+    @staticmethod
     def fromfloat(dval):
         """ Create a new bigint object from a float """
+        # This function is not marked as pure because it can raise
         sign = 1
         if isinf(dval) or isnan(dval):
             raise OverflowError
@@ -183,16 +193,21 @@
             frac -= float(bits)
             frac = math.ldexp(frac, SHIFT)
         return v
-    fromfloat = staticmethod(fromfloat)
 
+    @staticmethod
+    @jit.purefunction
+    @specialize.argtype(0)
     def fromrarith_int(i):
+        # This function is marked as pure, so you must not call it and
+        # then modify the result.
         return rbigint(*args_from_rarith_int(i))
-    fromrarith_int._annspecialcase_ = "specialize:argtype(0)"
-    fromrarith_int = staticmethod(fromrarith_int)
 
+    @staticmethod
+    @jit.purefunction
     def fromdecimalstr(s):
+        # This function is marked as pure, so you must not call it and
+        # then modify the result.
         return _decimalstr_to_bigint(s)
-    fromdecimalstr = staticmethod(fromdecimalstr)
 
     def toint(self):
         """
@@ -1841,7 +1856,7 @@
     elif s[p] == '+':
         p += 1
 
-    a = rbigint.fromint(0)
+    a = rbigint()
     tens = 1
     dig = 0
     ord0 = ord('0')
@@ -1859,7 +1874,7 @@
 
 def parse_digit_string(parser):
     # helper for objspace.std.strutil
-    a = rbigint.fromint(0)
+    a = rbigint()
     base = parser.base
     digitmax = BASE_MAX[base]
     tens, dig = 1, 0