xref: /gem5/src/arch/sparc/isa/formats/nop.isa

// Copyright (c) 2006 The Regents of The University of Michigan
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are
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// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
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// 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
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// 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
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//
// Authors: Gabe Black
//          Steve Reinhardt

////////////////////////////////////////////////////////////////////
//
// Nop instruction
//

output header {{
        /**
         * Nop class.
         */
        class Nop : public SparcStaticInst
        {
          public:
            // Constructor
            Nop(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
                SparcStaticInst(mnem, _machInst, __opClass)
            {
            }

            // All Nop instructions do the same thing, so this can be
            // defined here. Nops can be defined directly, so there needs
            // to be a default implementation
            Fault execute(%(CPU_exec_context)s *xc,
                Trace::InstRecord *traceData) const
            {
                //Nothing to see here, move along
                return NoFault;
            }

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

output decoder {{
        std::string Nop::generateDisassembly(Addr pc,
                const SymbolTable *symtab) const
        {
            std::stringstream response;
            printMnemonic(response, mnemonic);
            return response.str();
        }
}};

def template NopExecute {{
        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
                Trace::InstRecord *traceData) const
        {
            //Nothing to see here, move along
            return NoFault;
        }
}};

// Primary format for integer operate instructions:
def format Nop(code, *opt_flags) {{
        orig_code = code
        cblk = CodeBlock(code)
        iop = InstObjParams(name, Name, 'Nop', cblk, opt_flags)
        header_output = BasicDeclare.subst(iop)
        decoder_output = BasicConstructor.subst(iop)
        decode_block = BasicDecode.subst(iop)
        exec_output = NopExecute.subst(iop)
}};