From: Robert Bradshaw <robertwb@math.washington.edu>
Date: Tue, 16 Mar 2010 19:23:55 +0000 (-0700)
Subject: Another object -> bint optimization.
X-Git-Tag: 0.13.beta0~277
X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=0bc3d7b7b1d544ddad5c5cc73d270d6dfe41a93b;p=cython.git

Another object -> bint optimization.

__Pyx_PyObject_IsTrue now has only a single branch, even at -O0.
(The bitwise | is intentional.) This is only a 2.5% or so speedup
in my microbenchmarks, but it's something.
---

diff --git a/Cython/Compiler/PyrexTypes.py b/Cython/Compiler/PyrexTypes.py
index 3ef2eef9..19dd80dc 100755
--- a/Cython/Compiler/PyrexTypes.py
+++ b/Cython/Compiler/PyrexTypes.py
@@ -2485,12 +2485,13 @@ static CYTHON_INLINE size_t __Pyx_PyInt_AsSize_t(PyObject*);
 
 """ + type_conversion_predeclarations
 
+# Note: __Pyx_PyObject_IsTrue is written to minimize branching.
 type_conversion_functions = """
 /* Type Conversion Functions */
 
 static CYTHON_INLINE int __Pyx_PyObject_IsTrue(PyObject* x) {
-   if (x == Py_True) return 1;
-   else if ((x == Py_False) || (x == Py_None)) return 0;
+   int is_true = x == Py_True;
+   if (is_true | (x == Py_False) | (x == Py_None)) return is_true;
    else return PyObject_IsTrue(x);
 }