gem5/src/arch/riscv/isa/formats/mem.isa

// -*- mode:c++ -*-

// Copyright (c) 2015 RISC-V Foundation
// Copyright (c) 2016 The University of Virginia
// All rights reserved.
//
// 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: Alec Roelke

////////////////////////////////////////////////////////////////////
//
// Memory operation instructions
//
output header {{
    class Load : public RiscvStaticInst
    {
      public:
        /// Displacement for EA calculation (signed).
        int64_t ldisp;

      protected:
        /// Memory request flags.  See mem_req_base.hh.
        Request::Flags memAccessFlags;

        /// Constructor
        Load(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
            : RiscvStaticInst(mnem, _machInst, __opClass), ldisp(IMM12)
        {
            if (IMMSIGN > 0)
                ldisp |= ~((uint64_t)0xFFF);
        }

        std::string
        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
    };

    class Store : public RiscvStaticInst
    {
      public:
        /// Displacement for EA calculation (signed).
        int64_t sdisp;

      protected:
        /// Memory request flags.  See mem_req_base.hh.
        Request::Flags memAccessFlags;

        /// Constructor
        Store(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
            : RiscvStaticInst(mnem, _machInst, __opClass), sdisp(IMM5)
        {
            sdisp |= IMM7 << 5;
            if (IMMSIGN > 0)
                sdisp |= ~((uint64_t)0xFFF);
        }

        std::string
        generateDisassembly(Addr pc, const SymbolTable *symtab) const;
    };

}};


output decoder {{
    std::string
    Load::generateDisassembly(Addr pc, const SymbolTable *symtab) const
    {
        std::stringstream ss;
        ss << mnemonic << ' ' << regName(_destRegIdx[0]) << ", " << ldisp <<
            '(' << regName(_srcRegIdx[0]) << ')';
        return ss.str();
    }

    std::string
    Store::generateDisassembly(Addr pc, const SymbolTable *symtab) const
    {
        std::stringstream ss;
        ss << mnemonic << ' ' << regName(_srcRegIdx[1]) << ", " << sdisp <<
            '(' << regName(_srcRegIdx[0]) << ')';
        return ss.str();
    }
}};

def template LoadStoreDeclare {{
    /**
     * Static instruction class for "%(mnemonic)s".
     */
    class %(class_name)s : public %(base_class)s
    {
      public:
        /// Constructor.
        %(class_name)s(ExtMachInst machInst);

        %(BasicExecDeclare)s

        %(EACompDeclare)s

        %(InitiateAccDeclare)s

        %(CompleteAccDeclare)s
    };
}};

def template EACompDeclare {{
    Fault
    eaComp(%(CPU_exec_context)s *, Trace::InstRecord *) const;
}};

def template InitiateAccDeclare {{
    Fault
    initiateAcc(%(CPU_exec_context)s *, Trace::InstRecord *) const;
}};


def template CompleteAccDeclare {{
    Fault
    completeAcc(PacketPtr, %(CPU_exec_context)s *, Trace::InstRecord *) const;
}};

def template LoadStoreConstructor {{
    %(class_name)s::%(class_name)s(ExtMachInst machInst):
        %(base_class)s("%(mnemonic)s", machInst, %(op_class)s)
    {
        %(constructor)s;
    }
}};

def template EACompExecute {{
    Fault
    %(class_name)s::eaComp(CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Addr EA;
        Fault fault = NoFault;

        %(op_decl)s;
        %(op_rd)s;
        %(ea_code)s;

        if (fault == NoFault) {
            %(op_wb)s;
            xc->setEA(EA);
        }

        return fault;
    }
}};

let {{
def LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
        base_class, postacc_code='', decode_template=BasicDecode,
        exec_template_base=''):
    # Make sure flags are in lists (convert to lists if not).
    mem_flags = makeList(mem_flags)
    inst_flags = makeList(inst_flags) # + ['IsNonSpeculative']

    iop = InstObjParams(name, Name, base_class,
        { 'ea_code':ea_code, 'memacc_code':memacc_code,
        'postacc_code':postacc_code }, inst_flags)

    if mem_flags:
        mem_flags = [ 'Request::%s' % flag for flag in mem_flags ]
        s = '\n\tmemAccessFlags = ' + string.join(mem_flags, '|') + ';'
        iop.constructor += s

    # select templates

    # The InitiateAcc template is the same for StoreCond templates as the
    # corresponding Store template..
    StoreCondInitiateAcc = StoreInitiateAcc

    fullExecTemplate = eval(exec_template_base + 'Execute')
    initiateAccTemplate = eval(exec_template_base + 'InitiateAcc')
    completeAccTemplate = eval(exec_template_base + 'CompleteAcc')

    # (header_output, decoder_output, decode_block, exec_output)
    return (LoadStoreDeclare.subst(iop),
        LoadStoreConstructor.subst(iop),
        decode_template.subst(iop),
        fullExecTemplate.subst(iop) +
        EACompExecute.subst(iop) +
        initiateAccTemplate.subst(iop) +
        completeAccTemplate.subst(iop))
}};

def template LoadExecute {{
    Fault
    %(class_name)s::execute(CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Addr EA;
        Fault fault = NoFault;

        %(op_decl)s;
        %(op_rd)s;
        %(ea_code)s;

        if (fault == NoFault) {
            fault = readMemAtomic(xc, traceData, EA, Mem, memAccessFlags);
            %(memacc_code)s;
        }

        if (fault == NoFault) {
            %(op_wb)s;
        }

        return fault;
    }
}};

def template LoadInitiateAcc {{
    Fault
    %(class_name)s::initiateAcc(CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Addr EA;
        Fault fault = NoFault;

        %(op_src_decl)s;
        %(op_rd)s;
        %(ea_code)s;

        if (fault == NoFault) {
            fault = initiateMemRead(xc, traceData, EA, Mem, memAccessFlags);
        }

        return fault;
    }
}};

def template LoadCompleteAcc {{
    Fault
    %(class_name)s::completeAcc(PacketPtr pkt, CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Fault fault = NoFault;

        %(op_decl)s;
        %(op_rd)s;

        getMem(pkt, Mem, traceData);

        if (fault == NoFault) {
            %(memacc_code)s;
        }

        if (fault == NoFault) {
            %(op_wb)s;
        }

        return fault;
    }
}};

def template StoreExecute {{
    Fault
    %(class_name)s::execute(CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Addr EA;
        Fault fault = NoFault;

        %(op_decl)s;
        %(op_rd)s;
        %(ea_code)s;

        if (fault == NoFault) {
            %(memacc_code)s;
        }

        if (fault == NoFault) {
            fault = writeMemAtomic(xc, traceData, Mem, EA, memAccessFlags,
                nullptr);
        }

        if (fault == NoFault) {
            %(postacc_code)s;
        }

        if (fault == NoFault) {
            %(op_wb)s;
        }

        return fault;
    }
}};

def template StoreInitiateAcc {{
    Fault
    %(class_name)s::initiateAcc(CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Addr EA;
        Fault fault = NoFault;

        %(op_decl)s;
        %(op_rd)s;
        %(ea_code)s;

        if (fault == NoFault) {
            %(memacc_code)s;
        }

        if (fault == NoFault) {
            fault = writeMemTiming(xc, traceData, Mem, EA,
                memAccessFlags, nullptr);
        }

        if (fault == NoFault) {
            %(op_wb)s;
        }

        return fault;
    }
}};

def template StoreCompleteAcc {{
    Fault
    %(class_name)s::completeAcc(PacketPtr pkt, CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        return NoFault;
    }
}};

def template StoreCondExecute {{
    Fault %(class_name)s::execute(CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Addr EA;
        Fault fault = NoFault;
        uint64_t result;

        %(op_decl)s;
        %(op_rd)s;
        %(ea_code)s;

        if (fault == NoFault) {
            %(memacc_code)s;
        }

        if (fault == NoFault) {
            fault = writeMemAtomic(xc, traceData, Mem, EA, memAccessFlags,
                &result);
            // RISC-V has the opposite convention gem5 has for success flags,
            // so we invert the result here.
            result = !result;
        }

        if (fault == NoFault) {
            %(postacc_code)s;
        }

        if (fault == NoFault) {
            %(op_wb)s;
        }

        return fault;
    }
}};

def template StoreCondCompleteAcc {{
    Fault %(class_name)s::completeAcc(Packet *pkt, CPU_EXEC_CONTEXT *xc,
        Trace::InstRecord *traceData) const
    {
        Fault fault = NoFault;

        %(op_dest_decl)s;

        // RISC-V has the opposite convention gem5 has for success flags,
        // so we invert the result here.
        uint64_t result = !pkt->req->getExtraData();

        if (fault == NoFault) {
            %(postacc_code)s;
        }

        if (fault == NoFault) {
            %(op_wb)s;
        }

        return fault;
    }
}};

def format Load(memacc_code, ea_code = {{EA = Rs1 + ldisp;}}, mem_flags=[],
        inst_flags=[]) {{
    (header_output, decoder_output, decode_block, exec_output) = \
        LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
        'Load', exec_template_base='Load')
}};

def format Store(memacc_code, ea_code={{EA = Rs1 + sdisp;}}, mem_flags=[],
        inst_flags=[]) {{
    (header_output, decoder_output, decode_block, exec_output) = \
        LoadStoreBase(name, Name, ea_code, memacc_code, mem_flags, inst_flags,
        'Store', exec_template_base='Store')
}};

def format StoreCond(memacc_code, postacc_code, ea_code={{EA = Rs1;}},
        mem_flags=[], inst_flags=[], aq=0, rl=0) {{
    if aq:
        mem_flags = makeList(mem_flags) + ["ACQUIRE"]
    if rl:
        mem_flags = makeList(mem_flags) + ["RELEASE"]
    (header_output, decoder_output, decode_block, exec_output) = LoadStoreBase(
            name, Name, ea_code, memacc_code, mem_flags, inst_flags, 'Store',
            postacc_code, exec_template_base='StoreCond')
}};

def format LoadReserved(memacc_code, ea_code={{EA = Rs1;}}, mem_flags=[],
        inst_flags=[], aq=0, rl=0) {{
    if aq:
        mem_flags = makeList(mem_flags) + ["ACQUIRE"]
    if rl:
        mem_flags = makeList(mem_flags) + ["RELEASE"]
    (header_output, decoder_output, decode_block, exec_output) = LoadStoreBase(
            name, Name, ea_code, memacc_code, mem_flags, inst_flags, 'Load',
            exec_template_base='Load')
}};