tdf#89665: i18npool: speed up TextSearch::searchForward()

There does not appear to be a good reason why searchForward() needs to
call transliterate() on the entire passed string.

Restricting it to the passed range speeds it up from 104 billion to 0.19
billion callgrind cycles when built with GCC 4.9.2 -m32 -Os.

Change-Id: I440f16c34f38659b64f1eb60c50f0e414e3dfee8

i18npool/source/search/textsearch.cxx

@@ -232,25 +232,22 @@ SearchResult TextSearch::searchForward( const OUString& searchStr, sal_Int32 sta
     SearchResult sres;
 
     OUString in_str(searchStr);
-    sal_Int32 newStartPos = startPos;
-    sal_Int32 newEndPos = endPos;
 
     bUsePrimarySrchStr = true;
 
     if ( xTranslit.is() )
     {
         // apply normal transliteration (1<->1, 1<->0)
-        com::sun::star::uno::Sequence <sal_Int32> offset( in_str.getLength());
-        in_str = xTranslit->transliterate( searchStr, 0, in_str.getLength(), offset );
+        com::sun::star::uno::Sequence<sal_Int32> offset(endPos - startPos);
+        in_str = xTranslit->transliterate( searchStr, startPos, endPos - startPos, offset );
 
         // JP 20.6.2001: also the start and end positions must be corrected!
-        if( startPos )
-            newStartPos = FindPosInSeq_Impl( offset, startPos );
+        sal_Int32 const newStartPos =
+            (startPos == 0) ? 0 : FindPosInSeq_Impl( offset, startPos );
 
-        if( endPos < searchStr.getLength() )
-            newEndPos = FindPosInSeq_Impl( offset, endPos );
-        else
-            newEndPos = in_str.getLength();
+        sal_Int32 const newEndPos = (endPos < searchStr.getLength())
+            ? FindPosInSeq_Impl( offset, endPos )
+            : in_str.getLength();
 
         sres = (this->*fnForward)( in_str, newStartPos, newEndPos );
 
@@ -264,14 +261,14 @@ SearchResult TextSearch::searchForward( const OUString& searchStr, sal_Int32 sta
             for ( sal_Int32 k = 0; k < nGroups; k++ )
             {
                 const sal_Int32 nStart = sres.startOffset[k];
-                if (nStart > 0)
+                if (startPos > 0 || nStart > 0)
                     sres.startOffset[k] = (nStart < nOffsets ? offset[nStart] : (offset[nOffsets - 1] + 1));
                 // JP 20.6.2001: end is ever exclusive and then don't return
                 //               the position of the next character - return the
                 //               next position behind the last found character!
                 //               "a b c" find "b" must return 2,3 and not 2,4!!!
                 const sal_Int32 nStop = sres.endOffset[k];
-                if (nStop > 0)
+                if (startPos > 0 || nStop > 0)
                     sres.endOffset[k] = offset[(nStop <= nOffsets ? nStop : nOffsets) - 1] + 1;
             }
         }