src/arch/sparc/syscallreturn.hh

   1 /*
   2  * Copyright (c) 2003-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Gabe Black
  29  */
  30
  31 #ifndef __ARCH_SPARC_SYSCALLRETURN_HH__
  32 #define __ARCH_SPARC_SYSCALLRETURN_HH__
  33
  34 #include <inttypes.h>
  35
  36 #include "arch/sparc/regfile.hh"
  37
  38 class SyscallReturn
  39 {
  40   public:
  41     template <class T>
  42     SyscallReturn(T v, bool s)
  43     {
  44         retval = (uint64_t)v;
  45         success = s;
  46     }
  47
  48     template <class T>
  49     SyscallReturn(T v)
  50     {
  51         success = (v >= 0);
  52         retval = (uint64_t)v;
  53     }
  54
  55     ~SyscallReturn() {}
  56
  57     SyscallReturn& operator=(const SyscallReturn& s)
  58     {
  59         retval = s.retval;
  60         success = s.success;
  61         return *this;
  62     }
  63
  64     bool successful() { return success; }
  65     uint64_t value() { return retval; }
  66
  67     private:
  68     uint64_t retval;
  69     bool success;
  70 };
  71
  72 namespace SparcISA
  73 {
  74     static inline void setSyscallReturn(SyscallReturn return_value,
  75             RegFile *regs)
  76     {
  77         // check for error condition.  SPARC syscall convention is to
  78         // indicate success/failure in reg the carry bit of the ccr
  79         // and put the return value itself in the standard return value reg ().
  80         if (return_value.successful()) {
  81             // no error, clear XCC.C
  82             regs->setMiscReg(MISCREG_CCR, regs->readMiscReg(MISCREG_CCR) & 0xEE);
  83             regs->setIntReg(ReturnValueReg, return_value.value());
  84         } else {
  85             // got an error, set XCC.C
  86             regs->setMiscReg(MISCREG_CCR, regs->readMiscReg(MISCREG_CCR) | 0x11);
  87             regs->setIntReg(ReturnValueReg, return_value.value());
  88         }
  89     }
  90 };
  91
  92 #endif