noop.isa (2750:1cca27adb880) noop.isa (2754:e3d023bc752c)
1// -*- mode:c++ -*-
2
1// -*- mode:c++ -*-
2
3// Copyright (c) 2006 The Regents of The University of Michigan
4// All rights reserved.
5//
6// Redistribution and use in source and binary forms, with or without
7// modification, are permitted provided that the following conditions are
8// met: redistributions of source code must retain the above copyright
9// notice, this list of conditions and the following disclaimer;
10// redistributions in binary form must reproduce the above copyright
11// notice, this list of conditions and the following disclaimer in the
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13// neither the name of the copyright holders nor the names of its
14// contributors may be used to endorse or promote products derived from
15// this software without specific prior written permission.
16//
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28//
29// Authors: Korey Sewell
30
3////////////////////////////////////////////////////////////////////
4//
5// Nop
6//
7
8output header {{
9 /**
10 * Static instruction class for no-ops. This is a leaf class.
11 */
12 class Nop : public MipsStaticInst
13 {
14 /// Disassembly of original instruction.
15 const std::string originalDisassembly;
16
17 public:
18 /// Constructor
19 Nop(const std::string _originalDisassembly, MachInst _machInst)
20 : MipsStaticInst("nop", _machInst, No_OpClass),
21 originalDisassembly(_originalDisassembly)
22 {
23 flags[IsNop] = true;
24 }
25
26 ~Nop() { }
27
28 std::string
29 generateDisassembly(Addr pc, const SymbolTable *symtab) const;
30
31 %(BasicExecDeclare)s
32 };
33}};
34
35output decoder {{
36 std::string Nop::generateDisassembly(Addr pc,
37 const SymbolTable *symtab) const
38 {
39 return csprintf("%-10s %s", "nop", originalDisassembly);
40 }
41
42 /// Helper function for decoding nops. Substitute Nop object
43 /// for original inst passed in as arg (and delete latter).
44 inline
45 MipsStaticInst *
46 makeNop(MipsStaticInst *inst)
47 {
48 std::string nop_str = "(" + inst->disassemble(0) + ")";
49 MipsStaticInst *nop = new Nop(nop_str, inst->machInst);
50 delete inst;
51 return nop;
52 }
53}};
54
55output exec {{
56 Fault
57 Nop::execute(%(CPU_exec_context)s *, Trace::InstRecord *) const
58 {
59 return NoFault;
60 }
61}};
62
63// Int & FP operate instructions use RD as dest, so check for
64// RD == 0 to detect nops
65def template RegNopCheckDecode {{
66 {
67 MipsStaticInst *i = new %(class_name)s(machInst);
68 //if (RD == 0) {
69 //i = makeNop(i);
70 //}
71 return i;
72 }
73}};
74
75def template OperateNopCheckDecode {{
76 {
77 MipsStaticInst *i = new %(class_name)s(machInst);
78 //if (RD == 0) {
79 // i = makeNop(i);
80 //}
81 return i;
82 }
83}};
84
85// IntImm & Memory instructions use Rt as dest, so check for
86// Rt == 0 to detect nops
87def template ImmNopCheckDecode {{
88 {
89 MipsStaticInst *i = new %(class_name)s(machInst);
90 //if (RT == 0) {
91 // i = makeNop(i);
92 // }
93 return i;
94 }
95}};
96
97
98// Like BasicOperate format, but generates NOP if RC/FC == 31
99def format BasicOperateWithNopCheck(code, *opt_args) {{
100 iop = InstObjParams(name, Name, 'MipsStaticInst', CodeBlock(code),
101 opt_args)
102 header_output = BasicDeclare.subst(iop)
103 decoder_output = BasicConstructor.subst(iop)
104 decode_block = OperateNopCheckDecode.subst(iop)
105 exec_output = BasicExecute.subst(iop)
106}};
107
108def format Nop() {{
109 decode_block = 'return new Nop(\"\",machInst);\n'
110}};
111
31////////////////////////////////////////////////////////////////////
32//
33// Nop
34//
35
36output header {{
37 /**
38 * Static instruction class for no-ops. This is a leaf class.
39 */
40 class Nop : public MipsStaticInst
41 {
42 /// Disassembly of original instruction.
43 const std::string originalDisassembly;
44
45 public:
46 /// Constructor
47 Nop(const std::string _originalDisassembly, MachInst _machInst)
48 : MipsStaticInst("nop", _machInst, No_OpClass),
49 originalDisassembly(_originalDisassembly)
50 {
51 flags[IsNop] = true;
52 }
53
54 ~Nop() { }
55
56 std::string
57 generateDisassembly(Addr pc, const SymbolTable *symtab) const;
58
59 %(BasicExecDeclare)s
60 };
61}};
62
63output decoder {{
64 std::string Nop::generateDisassembly(Addr pc,
65 const SymbolTable *symtab) const
66 {
67 return csprintf("%-10s %s", "nop", originalDisassembly);
68 }
69
70 /// Helper function for decoding nops. Substitute Nop object
71 /// for original inst passed in as arg (and delete latter).
72 inline
73 MipsStaticInst *
74 makeNop(MipsStaticInst *inst)
75 {
76 std::string nop_str = "(" + inst->disassemble(0) + ")";
77 MipsStaticInst *nop = new Nop(nop_str, inst->machInst);
78 delete inst;
79 return nop;
80 }
81}};
82
83output exec {{
84 Fault
85 Nop::execute(%(CPU_exec_context)s *, Trace::InstRecord *) const
86 {
87 return NoFault;
88 }
89}};
90
91// Int & FP operate instructions use RD as dest, so check for
92// RD == 0 to detect nops
93def template RegNopCheckDecode {{
94 {
95 MipsStaticInst *i = new %(class_name)s(machInst);
96 //if (RD == 0) {
97 //i = makeNop(i);
98 //}
99 return i;
100 }
101}};
102
103def template OperateNopCheckDecode {{
104 {
105 MipsStaticInst *i = new %(class_name)s(machInst);
106 //if (RD == 0) {
107 // i = makeNop(i);
108 //}
109 return i;
110 }
111}};
112
113// IntImm & Memory instructions use Rt as dest, so check for
114// Rt == 0 to detect nops
115def template ImmNopCheckDecode {{
116 {
117 MipsStaticInst *i = new %(class_name)s(machInst);
118 //if (RT == 0) {
119 // i = makeNop(i);
120 // }
121 return i;
122 }
123}};
124
125
126// Like BasicOperate format, but generates NOP if RC/FC == 31
127def format BasicOperateWithNopCheck(code, *opt_args) {{
128 iop = InstObjParams(name, Name, 'MipsStaticInst', CodeBlock(code),
129 opt_args)
130 header_output = BasicDeclare.subst(iop)
131 decoder_output = BasicConstructor.subst(iop)
132 decode_block = OperateNopCheckDecode.subst(iop)
133 exec_output = BasicExecute.subst(iop)
134}};
135
136def format Nop() {{
137 decode_block = 'return new Nop(\"\",machInst);\n'
138}};
139