target-openrisc/int_helper.c

   1 /*
   2  * OpenRISC int helper routines
   3  *
   4  * Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com>
   5  *                         Feng Gao <gf91597@gmail.com>
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "cpu.h"
  22 #include "helper.h"
  23 #include "exception.h"
  24 #include "qemu/host-utils.h"
  25
  26 target_ulong HELPER(ff1)(target_ulong x)
  27 {
  28 /*#ifdef TARGET_OPENRISC64
  29     return x ? ctz64(x) + 1 : 0;
  30 #else*/
  31     return x ? ctz32(x) + 1 : 0;
  32 /*#endif*/
  33 }
  34
  35 target_ulong HELPER(fl1)(target_ulong x)
  36 {
  37 /* not used yet, open it when we need or64.  */
  38 /*#ifdef TARGET_OPENRISC64
  39     return 64 - clz64(x);
  40 #else*/
  41     return 32 - clz32(x);
  42 /*#endif*/
  43 }
  44
  45 uint32_t HELPER(mul32)(CPUOpenRISCState *env,
  46                        uint32_t ra, uint32_t rb)
  47 {
  48     uint64_t result;
  49     uint32_t high, cy;
  50
  51     OpenRISCCPU *cpu = OPENRISC_CPU(ENV_GET_CPU(env));
  52
  53     result = (uint64_t)ra * rb;
  54     /* regisiers in or32 is 32bit, so 32 is NOT a magic number.
  55        or64 is not handled in this function, and not implement yet,
  56        TARGET_LONG_BITS for or64 is 64, it will break this function,
  57        so, we didn't use TARGET_LONG_BITS here.  */
  58     high = result >> 32;
  59     cy = result >> (32 - 1);
  60
  61     if ((cy & 0x1) == 0x0) {
  62         if (high == 0x0) {
  63             return result;
  64         }
  65     }
  66
  67     if ((cy & 0x1) == 0x1) {
  68         if (high == 0xffffffff) {
  69             return result;
  70         }
  71     }
  72
  73     cpu->env.sr |= (SR_OV | SR_CY);
  74     if (cpu->env.sr & SR_OVE) {
  75         raise_exception(cpu, EXCP_RANGE);
  76     }
  77
  78     return result;
  79 }