Add a preliminary pass on mixed precision files

modules/precision_generator/codegen.py

@@ -181,7 +181,46 @@ class SourceFile( object ):
 
     # --------------------
     def _substitute( self, text, precision ):
-        '''Apply substitutions to text for given precision.'''
+        '''Apply substitutions to text for given precision.
+        If we use mixed precision algrotihm as input and output, we
+        apply a first pass from single precision, and then the mixed
+        one.
+        '''
+        if self._src[0] == 'x' and precision[0] == 'x':
+            precfrom = self._src[1]
+            precto   = precision[1]
+
+            try:
+                # Get substitution table based on self._table
+                subs_o = self._subs.subs[         self._table ]  # original
+                subs_s = self._subs.subs_search[  self._table ]  # compiled as search regexp
+                subs_r = self._subs.subs_replace[ self._table ]  # with regexp removed for replacement
+
+                # Get which column is from and to.
+                header = subs_o[0]
+                jfrom = header.index( precfrom )
+                jto   = header.index( precto )
+            except Exception as err:
+                print( "Error: bad table or precision in '%s', @precisions %s %s -> %s:" %
+                       (self._filename, self._table, precfrom, self._dsts), file=sys.stderr )
+                traceback.print_exc()
+                exit(1)
+
+            # Apply substitutions
+            try:
+                line = 0
+                for (orig, search, replace) in zip( subs_o[1:], subs_s[1:], subs_r[1:] ):
+                    line += 1
+                    if search[jfrom] is None:
+                        search[jfrom] = re.compile( orig[jfrom] )
+                    text = re.sub( search[jfrom], replace[jto], text )
+                # end
+            except Exception as err:
+                print( "Error: in row %d of substitution table '%s': %s" %
+                       (line, self._table, subs_o[line]), file=sys.stderr )
+                traceback.print_exc()
+                exit(1)
+
         try:
             # Get substitution table based on self._table
             subs_o = self._subs.subs[         self._table ]  # original