[pypy-commit] pypy default: add a small fastpath for comparisons of a box with itself

[cfbolz]

Author: Carl Friedrich Bolz <cfbolz at gmx.de>
Branch: 
Changeset: r74352:27a0edfa55b5
Date: 2014-11-06 12:47 +0100
http://bitbucket.org/pypy/pypy/changeset/27a0edfa55b5/

Log:	add a small fastpath for comparisons of a box with itself

	these either directly return true or false, depending on the
	comparison

diff --git a/rpython/jit/metainterp/pyjitpl.py b/rpython/jit/metainterp/pyjitpl.py
--- a/rpython/jit/metainterp/pyjitpl.py
+++ b/rpython/jit/metainterp/pyjitpl.py
@@ -33,6 +33,14 @@
 
 # ____________________________________________________________
 
+FASTPATHS_SAME_BOXES = {
+    "ne": "history.CONST_FALSE",
+    "eq": "history.CONST_TRUE",
+    "lt": "history.CONST_FALSE",
+    "le": "history.CONST_TRUE",
+    "gt": "history.CONST_FALSE",
+    "ge": "history.CONST_TRUE",
+}
 
 class MIFrame(object):
     debug = False
@@ -188,8 +196,6 @@
     # ------------------------------
 
     for _opimpl in ['int_add', 'int_sub', 'int_mul', 'int_floordiv', 'int_mod',
-                    'int_lt', 'int_le', 'int_eq',
-                    'int_ne', 'int_gt', 'int_ge',
                     'int_and', 'int_or', 'int_xor',
                     'int_rshift', 'int_lshift', 'uint_rshift',
                     'uint_lt', 'uint_le', 'uint_gt', 'uint_ge',
@@ -197,7 +203,6 @@
                     'float_add', 'float_sub', 'float_mul', 'float_truediv',
                     'float_lt', 'float_le', 'float_eq',
                     'float_ne', 'float_gt', 'float_ge',
-                    'ptr_eq', 'ptr_ne', 'instance_ptr_eq', 'instance_ptr_ne',
                     ]:
         exec py.code.Source('''
             @arguments("box", "box")
@@ -205,6 +210,18 @@
                 return self.execute(rop.%s, b1, b2)
         ''' % (_opimpl, _opimpl.upper())).compile()
 
+    for _opimpl in ['int_eq', 'int_ne', 'int_lt', 'int_le', 'int_gt', 'int_ge',
+                    'ptr_eq', 'ptr_ne',
+                    'instance_ptr_eq', 'instance_ptr_ne']:
+        exec py.code.Source('''
+            @arguments("box", "box")
+            def opimpl_%s(self, b1, b2):
+                if b1 is b2: # crude fast check
+                    return %s
+                return self.execute(rop.%s, b1, b2)
+        ''' % (_opimpl, FASTPATHS_SAME_BOXES[_opimpl.split("_")[-1]], _opimpl.upper())
+        ).compile()
+
     for _opimpl in ['int_add_ovf', 'int_sub_ovf', 'int_mul_ovf']:
         exec py.code.Source('''
             @arguments("box", "box")
@@ -340,10 +357,13 @@
         exec py.code.Source('''
             @arguments("box", "box", "label")
             def opimpl_goto_if_not_%s(self, b1, b2, target):
-                condbox = self.execute(rop.%s, b1, b2)
+                if b1 is b2:
+                    condbox = %s
+                else:
+                    condbox = self.execute(rop.%s, b1, b2)
                 self.opimpl_goto_if_not(condbox, target)
-        ''' % (_opimpl, _opimpl.upper())).compile()
-
+        ''' % (_opimpl, FASTPATHS_SAME_BOXES[_opimpl.split("_")[-1]], _opimpl.upper())
+        ).compile()
 
     def _establish_nullity(self, box, orgpc):
         value = box.nonnull()
diff --git a/rpython/jit/metainterp/test/test_ajit.py b/rpython/jit/metainterp/test/test_ajit.py
--- a/rpython/jit/metainterp/test/test_ajit.py
+++ b/rpython/jit/metainterp/test/test_ajit.py
@@ -4119,3 +4119,64 @@
         assert res == 42
         res = self.interp_operations(f, [-42])
         assert res == 0
+
+    def test_cmp_fastpaths(self):
+        class Z: pass
+        def make_int(cmp):
+            def f(x):
+                if cmp == 'eq':
+                    return x == x and x == x
+                if cmp == 'ne':
+                    return x != x or x != x
+                if cmp == 'lt':
+                    return x < x or x != x
+                if cmp == 'le':
+                    return x <= x and x <= x
+                if cmp == 'gt':
+                    return x > x or x > x
+                if cmp == 'ge':
+                    return x >= x and x >= x
+                assert 0
+            return f
+
+        def make_str(cmp):
+            def f(x):
+                x = str(x)
+                if cmp == 'eq':
+                    return x is x or x is x
+                if cmp == 'ne':
+                    return x is not x and x is not x
+                assert 0
+            return f
+
+        def make_object(cmp):
+            def f(x):
+                y = Z()
+                y.x = x
+                x = y
+                if cmp == 'eq':
+                    return x is x
+                if cmp == 'ne':
+                    return x is not x
+                assert 0
+            return f
+
+        for cmp in 'eq ne lt le gt ge'.split():
+            f = make_int(cmp)
+            res = self.interp_operations(f, [42])
+            assert res == f(42)
+            opname = "int_%s" % cmp
+            self.check_operations_history(**{opname: 0})
+
+        for cmp in 'eq ne'.split():
+            f = make_str(cmp)
+            res = self.interp_operations(f, [42])
+            assert res == f(42)
+            opname = "ptr_%s" % cmp
+            self.check_operations_history(**{opname: 0})
+
+            f = make_object(cmp)
+            res = self.interp_operations(f, [42])
+            assert res == f(42)
+            opname = "instance_ptr_%s" % cmp
+            self.check_operations_history(**{opname: 0})