[pypy-commit] pypy jit-short_from_state: make optimize_STRGETITEM reusing original result box when emitted

[hakanardo]

Author: Hakan Ardo <hakan at debian.org>
Branch: jit-short_from_state
Changeset: r45762:298d0583fc21
Date: 2011-07-17 17:05 +0200
http://bitbucket.org/pypy/pypy/changeset/298d0583fc21/

Log:	make optimize_STRGETITEM reusing original result box when emitted

diff --git a/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py b/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py
--- a/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py
+++ b/pypy/jit/metainterp/optimizeopt/test/test_optimizeopt.py
@@ -6467,6 +6467,62 @@
         """
         self.optimize_loop(ops, expected)
 
+    def test_loopinvariant_strgetitem(self):
+        ops = """
+        [p9, i1]
+        i843 = strgetitem(p9, i1)
+        call(i843, descr=nonwritedescr)
+        jump(p9, i1)
+        """
+        expected = """
+        [p9, i1, i2]
+        call(i2, descr=nonwritedescr)
+        jump(p9, i1, i2)
+        """
+        self.optimize_loop(ops, expected)
+
+    def test_loopinvariant_unicodelen(self):
+        ops = """
+        [p9]
+        i843 = unicodelen(p9)
+        call(i843, descr=nonwritedescr)
+        jump(p9)
+        """
+        expected = """
+        [p9, i2]
+        call(i2, descr=nonwritedescr)
+        jump(p9, i2)
+        """
+        self.optimize_loop(ops, expected)
+
+    def test_loopinvariant_unicodegetitem(self):
+        ops = """
+        [p9, i1]
+        i843 = unicodegetitem(p9, i1)
+        call(i843, descr=nonwritedescr)
+        jump(p9, i1)
+        """
+        expected = """
+        [p9, i1, i2]
+        call(i2, descr=nonwritedescr)
+        jump(p9, i1, i2)
+        """
+        self.optimize_loop(ops, expected)
+
+    def test_loopinvariant_arraylen(self):
+        ops = """
+        [p9]
+        i843 = arraylen_gc(p9)
+        call(i843, descr=nonwritedescr)
+        jump(p9)
+        """
+        expected = """
+        [p9, i2]
+        call(i2, descr=nonwritedescr)
+        jump(p9, i2)
+        """
+        self.optimize_loop(ops, expected)
+
     def test_duplicated_virtual(self):
         ops = """
         [p1, p2]
diff --git a/pypy/jit/metainterp/optimizeopt/vstring.py b/pypy/jit/metainterp/optimizeopt/vstring.py
--- a/pypy/jit/metainterp/optimizeopt/vstring.py
+++ b/pypy/jit/metainterp/optimizeopt/vstring.py
@@ -349,7 +349,7 @@
     optimizer.emit_operation(ResOperation(rop.INT_SUB, [box1, box2], resbox))
     return resbox
 
-def _strgetitem(optimization, strbox, indexbox, mode):
+def _strgetitem(optimization, strbox, indexbox, mode, resbox=None):
     if isinstance(strbox, ConstPtr) and isinstance(indexbox, ConstInt):
         if mode is mode_string:
             s = strbox.getref(lltype.Ptr(rstr.STR))
@@ -357,6 +357,7 @@
         else:
             s = strbox.getref(lltype.Ptr(rstr.UNICODE))
             return ConstInt(ord(s.chars[indexbox.getint()]))
+    if not resbox:
     resbox = BoxInt()
     optimization.emit_operation(ResOperation(mode.STRGETITEM, [strbox, indexbox],
                                       resbox))
@@ -427,10 +428,11 @@
     def _optimize_STRGETITEM(self, op, mode):
         value = self.getvalue(op.getarg(0))
         vindex = self.getvalue(op.getarg(1))
-        vresult = self.strgetitem(value, vindex, mode)
+        vresult = self.strgetitem(value, vindex, mode, op.result)
+        if op.result not in self.optimizer.values:
         self.make_equal_to(op.result, vresult)
 
-    def strgetitem(self, value, vindex, mode):
+    def strgetitem(self, value, vindex, mode, result=None):
         value.ensure_nonnull()
         #
         if value.is_virtual() and isinstance(value, VStringSliceValue):
@@ -444,7 +446,7 @@
             if vindex.is_constant():
                 return value.getitem(vindex.box.getint())
         #
-        resbox = _strgetitem(self, value.force_box(), vindex.force_box(), mode)
+        resbox = _strgetitem(self, value.force_box(), vindex.force_box(), mode, result)
         return self.getvalue(resbox)
 
     def optimize_STRLEN(self, op):