nop.isa revision 12234:78ece221f9f5 
1// Copyright (c) 2006-2007 The Regents of The University of Michigan
2// All rights reserved.
3//
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14//
15// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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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
35// Per-cpu-model nop execute method.
36def template NopExec {{
37
38    Fault execute(ExecContext *xc, Trace::InstRecord *traceData) const
39    {
40        // Nothing to see here, move along
41        return NoFault;
42    }
43}};
44
45output header {{
46        /**
47         * Nop class.
48         */
49        class Nop : public SparcStaticInst
50        {
51          public:
52            // Constructor
53            Nop(const char *mnem, ExtMachInst _machInst, OpClass __opClass) :
54                SparcStaticInst(mnem, _machInst, __opClass)
55            {
56                flags[IsNop] = true;
57            }
58
59            // All Nop instructions do the same thing, so this can be
60            // defined here. Nops can be defined directly, so there
61            // needs to be a default implementation.  Interpolate via
62            // template so i gets expanded to a set of
63            // cpu-model-specific functions.
64            %(NopExec)s
65
66            std::string generateDisassembly(Addr pc,
67                    const SymbolTable *symtab) const;
68        };
69}};
70
71output decoder {{
72        std::string Nop::generateDisassembly(Addr pc,
73                const SymbolTable *symtab) const
74        {
75            std::stringstream response;
76            printMnemonic(response, mnemonic);
77            return response.str();
78        }
79}};
80
81def template NopExecute {{
82        Fault %(class_name)s::execute(ExecContext *xc,
83                Trace::InstRecord *traceData) const
84        {
85            // Nothing to see here, move along
86            return NoFault;
87        }
88}};
89
90// Primary format for integer operate instructions:
91def format Nop(code, *opt_flags) {{
92        iop = InstObjParams(name, Name, 'Nop', code, opt_flags)
93        header_output = BasicDeclare.subst(iop)
94        decoder_output = BasicConstructor.subst(iop)
95        decode_block = BasicDecode.subst(iop)
96        exec_output = NopExecute.subst(iop)
97}};
98