src/share/vm/opto/divnode.cpp

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   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "memory/allocation.inline.hpp"
  27 #include "opto/addnode.hpp"
  28 #include "opto/connode.hpp"

  29 #include "opto/divnode.hpp"
  30 #include "opto/machnode.hpp"

  31 #include "opto/matcher.hpp"
  32 #include "opto/mulnode.hpp"
  33 #include "opto/phaseX.hpp"
  34 #include "opto/subnode.hpp"
  35 
  36 // Portions of code courtesy of Clifford Click
  37 
  38 // Optimization - Graph Style
  39 
  40 #include <math.h>
  41 
  42 //----------------------magic_int_divide_constants-----------------------------
  43 // Compute magic multiplier and shift constant for converting a 32 bit divide
  44 // by constant into a multiply/shift/add series. Return false if calculations
  45 // fail.
  46 //
  47 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
  48 // minor type name and parameter changes.
  49 static bool magic_int_divide_constants(jint d, jint &M, jint &s) {
  50   int32_t p;




   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "memory/allocation.inline.hpp"
  27 #include "opto/addnode.hpp"
  28 #include "opto/constnode.hpp"
  29 #include "opto/convertnode.hpp"
  30 #include "opto/divnode.hpp"
  31 #include "opto/machnode.hpp"
  32 #include "opto/movenode.hpp"
  33 #include "opto/matcher.hpp"
  34 #include "opto/mulnode.hpp"
  35 #include "opto/phaseX.hpp"
  36 #include "opto/subnode.hpp"
  37 
  38 // Portions of code courtesy of Clifford Click
  39 
  40 // Optimization - Graph Style
  41 
  42 #include <math.h>
  43 
  44 //----------------------magic_int_divide_constants-----------------------------
  45 // Compute magic multiplier and shift constant for converting a 32 bit divide
  46 // by constant into a multiply/shift/add series. Return false if calculations
  47 // fail.
  48 //
  49 // Borrowed almost verbatim from Hacker's Delight by Henry S. Warren, Jr. with
  50 // minor type name and parameter changes.
  51 static bool magic_int_divide_constants(jint d, jint &M, jint &s) {
  52   int32_t p;