From 72f86cfb4e28f2e64c0208f42a67cefaabf5a913 Mon Sep 17 00:00:00 2001
From: Camille GILLOT <gillot.camille@gmail.com>
Date: Tue, 7 Jun 2016 20:27:05 +0200
Subject: [PATCH] Memorize the C string representation.

For some cases, the computation of the C
string for inline using _getRepresentation
takes a substantial amount of time.

Here, we memorize the computed C code and argument dictionary.
The argDict used to store the values of the required variables.
Now it stores the variables themselves,
and the values are retrieved by _execInline.
---
 fipy/variables/variable.py | 52 ++++++++++++++++++++++++--------------
 1 file changed, 33 insertions(+), 19 deletions(-)

diff --git a/fipy/variables/variable.py b/fipy/variables/variable.py
index 1398b54e73..a63c109a4d 100644
--- a/fipy/variables/variable.py
+++ b/fipy/variables/variable.py
@@ -386,6 +386,26 @@ def _getCIndexString(self, shape):
             else:
                 return '[i + j * ni + k * ni * nj]'
 
+    def _getCvalue(self):
+         """
+         Generate the value to be used in inline.
+         """
+         v = self.value
+
+         if type(v) not in (type(numerix.array(1)),):
+             varray = numerix.array(v)
+         else:
+             varray = v
+
+         if len(varray.shape) == 0:
+             if varray.dtype in (numerix.array(1).dtype,):
+                 return int(varray)
+             elif varray.dtype in (numerix.array(1.).dtype,):
+                 return float(varray)
+             else:
+                 return varray
+         else:
+             return varray
 
     def _getCstring(self, argDict={}, id="", freshen=None):
          """
@@ -423,23 +443,7 @@ def _getCstring(self, argDict={}, id="", freshen=None):
          """
 
          identifier = 'var%s' % (id)
-
-         v = self.value
-
-         if type(v) not in (type(numerix.array(1)),):
-             varray = numerix.array(v)
-         else:
-             varray = v
-
-         if len(varray.shape) == 0:
-             if varray.dtype in (numerix.array(1).dtype,):
-                 argDict[identifier] = int(varray)
-             elif varray.dtype in (numerix.array(1.).dtype,):
-                 argDict[identifier] = float(varray)
-             else:
-                 argDict[identifier] = varray
-         else:
-             argDict[identifier] = varray
+         argDict[identifier] = self
 
          try:
              shape = self.opShape
@@ -892,8 +896,18 @@ def _execInline(self, comment=None):
         """
 
         from fipy.tools import inline
-        argDict = {}
-        string = self._getCstring(argDict=argDict, freshen=True) + ';'
+        try:
+            argDict = self._c_argDict
+            string  = self._c_string
+        except AttributeError:
+            argDict = {}
+            string = self._getCstring(argDict=argDict, freshen=True) + ';'
+            self._c_argDict = dict(argDict)
+            self._c_string  = string
+
+        # _getCstring only returns variables,
+        # we need the values for the C code
+        argDict = {k: v._getCvalue() for k,v in argDict.iteritems()}
 
         try:
             shape = self.opShape