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// -*- mode:c++ -*-
// Copyright (c) 2018 ARM Limited
// All rights reserved
//
// The license below extends only to copyright in the software and shall
// not be construed as granting a license to any other intellectual
// property including but not limited to intellectual property relating
// to a hardware implementation of the functionality of the software
// licensed hereunder.  You may use the software subject to the license
// terms below provided that you ensure that this notice is replicated
// unmodified and in its entirety in all distributions of the software,
// modified or unmodified, in source code or in binary form.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Giacomo Travaglini

//
// A new class of Semihosting constructor templates has been added.
// Their main purpose is to check if the Exception Generation
// Instructions (HLT, SVC) are actually a semihosting command.
// If that is the case, the IsMemBarrier flag is raised, so that
// in the O3 model we perform a coherent memory access during
// the semihosting operation.
// Please note: since we don't have a thread context pointer in the
// constructor we cannot check if semihosting is enabled in the
// system. This is not affecting functional correctness, it just
// means O3 models will flush the LSQ even if semihosting is disabled
// when a semihosting immediate is recognized.

def template SemihostConstructor {{
    %(class_name)s::%(class_name)s(ExtMachInst machInst, uint64_t _imm)
        : %(base_class)s("%(mnemonic)s", machInst, %(op_class)s, _imm)
    {
        %(constructor)s;
        if (!(condCode == COND_AL || condCode == COND_UC)) {
            for (int x = 0; x < _numDestRegs; x++) {
                _srcRegIdx[_numSrcRegs++] = _destRegIdx[x];
            }
        }

        // In AArch32 semihosting commands can be issued by either
        // SVC and HLT instructions. Another degree of freedom
        // is added by the operating mode (Arm or Thumb)
        auto semihost_imm = machInst.thumb? %(thumb_semihost)s :
                                            %(arm_semihost)s;
        if (_imm == semihost_imm) {
            flags[IsMemBarrier] = true;
        }
    }
}};

def template SemihostConstructor64 {{
    %(class_name)s::%(class_name)s(ExtMachInst machInst, uint64_t _imm)
        : %(base_class)s("%(mnemonic)s", machInst, %(op_class)s, _imm)
    {
        %(constructor)s;

        // In AArch64 there is only one instruction for issuing
        // semhosting commands: HLT #0xF000
        if (_imm == 0xF000) {
            flags[IsMemBarrier] = true;
        }
    }
}};