nop.isa revision 2632:1bb2f91485ea 
1// Copyright (c) 2006 The Regents of The University of Michigan
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met: redistributions of source code must retain the above copyright
7// notice, this list of conditions and the following disclaimer;
8// redistributions in binary form must reproduce the above copyright
9// notice, this list of conditions and the following disclaimer in the
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13// this software without specific prior written permission.
14//
15// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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20// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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25// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26//
27// Authors: Gabe Black
28//          Steve Reinhardt
29
30////////////////////////////////////////////////////////////////////
31//
32// Nop instruction
33//
34
35output header {{
36        /**
37         * Nop class.
38         */
39        class Nop : public SparcStaticInst
40        {
41          public:
42            // Constructor
43            Nop(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
44                SparcStaticInst(mnem, _machInst, __opClass)
45            {
46            }
47
48            // All Nop instructions do the same thing, so this can be
49            // defined here. Nops can be defined directly, so there needs
50            // to be a default implementation
51            Fault execute(%(CPU_exec_context)s *xc,
52                Trace::InstRecord *traceData) const
53            {
54                //Nothing to see here, move along
55                return NoFault;
56            }
57
58            std::string generateDisassembly(Addr pc,
59                    const SymbolTable *symtab) const;
60        };
61}};
62
63output decoder {{
64        std::string Nop::generateDisassembly(Addr pc,
65                const SymbolTable *symtab) const
66        {
67            std::stringstream response;
68            printMnemonic(response, mnemonic);
69            return response.str();
70        }
71}};
72
73def template NopExecute {{
74        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
75                Trace::InstRecord *traceData) const
76        {
77            //Nothing to see here, move along
78            return NoFault;
79        }
80}};
81
82// Primary format for integer operate instructions:
83def format Nop(code, *opt_flags) {{
84        orig_code = code
85        cblk = CodeBlock(code)
86        iop = InstObjParams(name, Name, 'Nop', cblk, opt_flags)
87        header_output = BasicDeclare.subst(iop)
88        decoder_output = BasicConstructor.subst(iop)
89        decode_block = BasicDecode.subst(iop)
90        exec_output = NopExecute.subst(iop)
91}};
92