gem5/src/arch/alpha/isa/unimp.isa

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

// Copyright (c) 2003-2005 The Regents of The University of Michigan
// All rights reserved.
//
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//
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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//
// Authors: Steve Reinhardt

////////////////////////////////////////////////////////////////////
//
// Unimplemented instructions
//

output header {{
    /**
     * Static instruction class for unimplemented instructions that
     * cause simulator termination.  Note that these are recognized
     * (legal) instructions that the simulator does not support; the
     * 'Unknown' class is used for unrecognized/illegal instructions.
     * This is a leaf class.
     */
    class FailUnimplemented : public AlphaStaticInst
    {
      public:
        /// Constructor
        FailUnimplemented(const char *_mnemonic, ExtMachInst _machInst)
            : AlphaStaticInst(_mnemonic, _machInst, No_OpClass)
        {
            // don't call execute() (which panics) if we're on a
            // speculative path
            flags[IsNonSpeculative] = true;
        }

        %(BasicExecDeclare)s

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

    /**
     * Base class for unimplemented instructions that cause a warning
     * to be printed (but do not terminate simulation).  This
     * implementation is a little screwy in that it will print a
     * warning for each instance of a particular unimplemented machine
     * instruction, not just for each unimplemented opcode.  Should
     * probably make the 'warned' flag a static member of the derived
     * class.
     */
    class WarnUnimplemented : public AlphaStaticInst
    {
      private:
        /// Have we warned on this instruction yet?
        mutable bool warned;

      public:
        /// Constructor
        WarnUnimplemented(const char *_mnemonic, ExtMachInst _machInst)
            : AlphaStaticInst(_mnemonic, _machInst, No_OpClass), warned(false)
        {
            // don't call execute() (which panics) if we're on a
            // speculative path
            flags[IsNonSpeculative] = true;
        }

        %(BasicExecDeclare)s

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

output decoder {{
    std::string
    FailUnimplemented::generateDisassembly(Addr pc,
                                           const SymbolTable *symtab) const
    {
        return csprintf("%-10s (unimplemented)", mnemonic);
    }

    std::string
    WarnUnimplemented::generateDisassembly(Addr pc,
                                           const SymbolTable *symtab) const
    {
#ifdef SS_COMPATIBLE_DISASSEMBLY
        return csprintf("%-10s", mnemonic);
#else
        return csprintf("%-10s (unimplemented)", mnemonic);
#endif
    }
}};

output exec {{
    Fault
    FailUnimplemented::execute(CPU_EXEC_CONTEXT *xc,
                               Trace::InstRecord *traceData) const
    {
        panic("attempt to execute unimplemented instruction '%s' "
              "(inst 0x%08x, opcode 0x%x)", mnemonic, machInst, OPCODE);
        return std::make_shared<UnimplementedOpcodeFault>();
    }

    Fault
    WarnUnimplemented::execute(CPU_EXEC_CONTEXT *xc,
                               Trace::InstRecord *traceData) const
    {
        if (!warned) {
            warn("instruction '%s' unimplemented\n", mnemonic);
            warned = true;
        }

        return NoFault;
    }
}};


def format FailUnimpl() {{
    iop = InstObjParams(name, 'FailUnimplemented')
    decode_block = BasicDecodeWithMnemonic.subst(iop)
}};

def format WarnUnimpl() {{
    iop = InstObjParams(name, 'WarnUnimplemented')
    decode_block = BasicDecodeWithMnemonic.subst(iop)
}};

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 AlphaStaticInst
    {
      public:
        /// Constructor
        Unknown(ExtMachInst _machInst)
            : AlphaStaticInst("unknown", _machInst, No_OpClass)
        {
            // don't call execute() (which panics) if we're on a
            // speculative path
            flags[IsNonSpeculative] = true;
        }

        %(BasicExecDeclare)s

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