xref: /gem5/src/arch/mips/isa/formats/unknown.isa

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

// 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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//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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//
// Authors: Korey Sewell

////////////////////////////////////////////////////////////////////
//
// Unknown instructions
//

output header {{
    /**
     * Static instruction class for unknown (illegal) instructions.
     * These cause simulator termination if they are executed in a
     * non-speculative mode.  This is a leaf class.
     */
    class Unknown : public MipsStaticInst
    {
      public:
        /// Constructor
        Unknown(MachInst _machInst)
            : MipsStaticInst("unknown", _machInst, No_OpClass)
        {
            // don't call execute() (which panics) if we're on a
            // speculative path
            flags[IsNonSpeculative] = true;
        }

        Fault execute(ExecContext *, Trace::InstRecord *) const override;

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

output decoder {{
    std::string
    Unknown::generateDisassembly(Addr pc, const SymbolTable *symtab) const
    {
        return csprintf("%-10s (inst 0x%x, opcode 0x%x, binary:%s)",
                        "unknown", machInst, OPCODE, inst2string(machInst));
    }
}};

output exec {{
    Fault
    Unknown::execute(ExecContext *xc, Trace::InstRecord *traceData) const
    {
        return std::make_shared<ReservedInstructionFault>();
    }
}};

def format Unknown() {{
    decode_block = 'return new Unknown(machInst);\n'
}};