1/*
2 * Copyright (c) 2003-2005 The Regents of The University of Michigan
3 * Copyright (c) 2013 Advanced Micro Devices, Inc.
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
12 * documentation and/or other materials provided with the distribution;
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: Steve Reinhardt
30 */
31
32#ifndef __CPU_STATIC_INST_HH__
33#define __CPU_STATIC_INST_HH__
34
35#include <bitset>
36#include <memory>
37#include <string>
38
39#include "arch/registers.hh"
40#include "arch/types.hh"
41#include "base/logging.hh"
42#include "base/refcnt.hh"
43#include "base/types.hh"
44#include "config/the_isa.hh"
45#include "cpu/op_class.hh"
46#include "cpu/reg_class.hh"
47#include "cpu/reg_class_impl.hh"
48#include "cpu/static_inst_fwd.hh"
49#include "cpu/thread_context.hh"
50#include "enums/StaticInstFlags.hh"
51#include "sim/byteswap.hh"
52
53// forward declarations
54class Packet;
55
56class ExecContext;
57
58class SymbolTable;
59
60namespace Trace {
61 class InstRecord;
62}
63
64/**
65 * Base, ISA-independent static instruction class.
66 *
67 * The main component of this class is the vector of flags and the
68 * associated methods for reading them. Any object that can rely
69 * solely on these flags can process instructions without being
70 * recompiled for multiple ISAs.
71 */
72class StaticInst : public RefCounted, public StaticInstFlags
73{
74 public:
75 /// Binary extended machine instruction type.
76 typedef TheISA::ExtMachInst ExtMachInst;
77
78 enum {
79 MaxInstSrcRegs = TheISA::MaxInstSrcRegs, //< Max source regs
80 MaxInstDestRegs = TheISA::MaxInstDestRegs //< Max dest regs
81 };
82
83 protected:
84
85 /// Flag values for this instruction.
86 std::bitset<Num_Flags> flags;
87
88 /// See opClass().
89 OpClass _opClass;
90
91 /// See numSrcRegs().
92 int8_t _numSrcRegs;
93
94 /// See numDestRegs().
95 int8_t _numDestRegs;
96
97 /// The following are used to track physical register usage
98 /// for machines with separate int & FP reg files.
99 //@{
100 int8_t _numFPDestRegs;
101 int8_t _numIntDestRegs;
102 int8_t _numCCDestRegs;
103 //@}
104
105 /** To use in architectures with vector register file. */
106 /** @{ */
107 int8_t _numVecDestRegs;
108 int8_t _numVecElemDestRegs;
109 /** @} */
110
111 public:
112
113 /// @name Register information.
114 /// The sum of numFPDestRegs(), numIntDestRegs(), numVecDestRegs() and
115 /// numVecelemDestRegs() equals numDestRegs(). The former two functions
116 /// are used to track physical register usage for machines with separate
117 /// int & FP reg files, the next two is for machines with vector register
118 /// file.
119 //@{
120 /// Number of source registers.
121 int8_t numSrcRegs() const { return _numSrcRegs; }
122 /// Number of destination registers.
123 int8_t numDestRegs() const { return _numDestRegs; }
124 /// Number of floating-point destination regs.
125 int8_t numFPDestRegs() const { return _numFPDestRegs; }
126 /// Number of integer destination regs.
127 int8_t numIntDestRegs() const { return _numIntDestRegs; }
128 /// Number of vector destination regs.
129 int8_t numVecDestRegs() const { return _numVecDestRegs; }
130 /// Number of vector element destination regs.
131 int8_t numVecElemDestRegs() const { return _numVecElemDestRegs; }
132 /// Number of coprocesor destination regs.
133 int8_t numCCDestRegs() const { return _numCCDestRegs; }
134 //@}
135
136 /// @name Flag accessors.
137 /// These functions are used to access the values of the various
138 /// instruction property flags. See StaticInst::Flags for descriptions
139 /// of the individual flags.
140 //@{
141
142 bool isNop() const { return flags[IsNop]; }
143
144 bool isMemRef() const { return flags[IsMemRef]; }
145 bool isLoad() const { return flags[IsLoad]; }
146 bool isStore() const { return flags[IsStore]; }
147 bool isStoreConditional() const { return flags[IsStoreConditional]; }
148 bool isInstPrefetch() const { return flags[IsInstPrefetch]; }
149 bool isDataPrefetch() const { return flags[IsDataPrefetch]; }
150 bool isPrefetch() const { return isInstPrefetch() ||
151 isDataPrefetch(); }
152
153 bool isInteger() const { return flags[IsInteger]; }
154 bool isFloating() const { return flags[IsFloating]; }
155 bool isVector() const { return flags[IsVector]; }
156 bool isCC() const { return flags[IsCC]; }
157
158 bool isControl() const { return flags[IsControl]; }
159 bool isCall() const { return flags[IsCall]; }
160 bool isReturn() const { return flags[IsReturn]; }
161 bool isDirectCtrl() const { return flags[IsDirectControl]; }
162 bool isIndirectCtrl() const { return flags[IsIndirectControl]; }
163 bool isCondCtrl() const { return flags[IsCondControl]; }
164 bool isUncondCtrl() const { return flags[IsUncondControl]; }
165 bool isCondDelaySlot() const { return flags[IsCondDelaySlot]; }
166
167 bool isThreadSync() const { return flags[IsThreadSync]; }
168 bool isSerializing() const { return flags[IsSerializing] ||
169 flags[IsSerializeBefore] ||
170 flags[IsSerializeAfter]; }
171 bool isSerializeBefore() const { return flags[IsSerializeBefore]; }
172 bool isSerializeAfter() const { return flags[IsSerializeAfter]; }
173 bool isSquashAfter() const { return flags[IsSquashAfter]; }
174 bool isMemBarrier() const { return flags[IsMemBarrier]; }
175 bool isWriteBarrier() const { return flags[IsWriteBarrier]; }
176 bool isNonSpeculative() const { return flags[IsNonSpeculative]; }
177 bool isQuiesce() const { return flags[IsQuiesce]; }
178 bool isIprAccess() const { return flags[IsIprAccess]; }
179 bool isUnverifiable() const { return flags[IsUnverifiable]; }
180 bool isSyscall() const { return flags[IsSyscall]; }
181 bool isMacroop() const { return flags[IsMacroop]; }
182 bool isMicroop() const { return flags[IsMicroop]; }
183 bool isDelayedCommit() const { return flags[IsDelayedCommit]; }
184 bool isLastMicroop() const { return flags[IsLastMicroop]; }
185 bool isFirstMicroop() const { return flags[IsFirstMicroop]; }
186 //This flag doesn't do anything yet
187 bool isMicroBranch() const { return flags[IsMicroBranch]; }
188 //@}
189
190 void setFirstMicroop() { flags[IsFirstMicroop] = true; }
191 void setLastMicroop() { flags[IsLastMicroop] = true; }
192 void setDelayedCommit() { flags[IsDelayedCommit] = true; }
193 void setFlag(Flags f) { flags[f] = true; }
194
195 /// Operation class. Used to select appropriate function unit in issue.
196 OpClass opClass() const { return _opClass; }
197
198
199 /// Return logical index (architectural reg num) of i'th destination reg.
200 /// Only the entries from 0 through numDestRegs()-1 are valid.
201 const RegId& destRegIdx(int i) const { return _destRegIdx[i]; }
202
203 /// Return logical index (architectural reg num) of i'th source reg.
204 /// Only the entries from 0 through numSrcRegs()-1 are valid.
205 const RegId& srcRegIdx(int i) const { return _srcRegIdx[i]; }
206
207 /// Pointer to a statically allocated "null" instruction object.
208 static StaticInstPtr nullStaticInstPtr;
209
210 /// Pointer to a statically allocated generic "nop" instruction object.
211 static StaticInstPtr nopStaticInstPtr;
212
213 /// The binary machine instruction.
214 const ExtMachInst machInst;
215
216 protected:
217
218 /// See destRegIdx().
219 RegId _destRegIdx[MaxInstDestRegs];
220 /// See srcRegIdx().
221 RegId _srcRegIdx[MaxInstSrcRegs];
222
223 /**
224 * Base mnemonic (e.g., "add"). Used by generateDisassembly()
225 * methods. Also useful to readily identify instructions from
226 * within the debugger when #cachedDisassembly has not been
227 * initialized.
228 */
229 const char *mnemonic;
230
231 /**
232 * String representation of disassembly (lazily evaluated via
233 * disassemble()).
234 */
235 mutable std::string *cachedDisassembly;
236
237 /**
238 * Internal function to generate disassembly string.
239 */
240 virtual std::string
241 generateDisassembly(Addr pc, const SymbolTable *symtab) const = 0;
242
243 /// Constructor.
244 /// It's important to initialize everything here to a sane
245 /// default, since the decoder generally only overrides
246 /// the fields that are meaningful for the particular
247 /// instruction.
248 StaticInst(const char *_mnemonic, ExtMachInst _machInst, OpClass __opClass)
249 : _opClass(__opClass), _numSrcRegs(0), _numDestRegs(0),
250 _numFPDestRegs(0), _numIntDestRegs(0), _numCCDestRegs(0),
251 _numVecDestRegs(0), _numVecElemDestRegs(0), machInst(_machInst),
252 mnemonic(_mnemonic), cachedDisassembly(0)
253 { }
254
255 public:
256 virtual ~StaticInst();
257
258 virtual Fault execute(ExecContext *xc,
259 Trace::InstRecord *traceData) const = 0;
260
261 virtual Fault initiateAcc(ExecContext *xc,
262 Trace::InstRecord *traceData) const
263 {
264 panic("initiateAcc not defined!");
265 }
266
267 virtual Fault completeAcc(Packet *pkt, ExecContext *xc,
268 Trace::InstRecord *traceData) const
269 {
270 panic("completeAcc not defined!");
271 }
272
273 virtual void advancePC(TheISA::PCState &pcState) const = 0;
274
275 /**
276 * Return the microop that goes with a particular micropc. This should
277 * only be defined/used in macroops which will contain microops
278 */
279 virtual StaticInstPtr fetchMicroop(MicroPC upc) const;
280
281 /**
282 * Return the target address for a PC-relative branch.
283 * Invalid if not a PC-relative branch (i.e. isDirectCtrl()
284 * should be true).
285 */
286 virtual TheISA::PCState branchTarget(const TheISA::PCState &pc) const;
287
288 /**
289 * Return the target address for an indirect branch (jump). The
290 * register value is read from the supplied thread context, so
291 * the result is valid only if the thread context is about to
292 * execute the branch in question. Invalid if not an indirect
293 * branch (i.e. isIndirectCtrl() should be true).
294 */
295 virtual TheISA::PCState branchTarget(ThreadContext *tc) const;
296
297 /**
298 * Return true if the instruction is a control transfer, and if so,
299 * return the target address as well.
300 */
301 bool hasBranchTarget(const TheISA::PCState &pc, ThreadContext *tc,
302 TheISA::PCState &tgt) const;
303
304 /**
305 * Return string representation of disassembled instruction.
306 * The default version of this function will call the internal
307 * virtual generateDisassembly() function to get the string,
308 * then cache it in #cachedDisassembly. If the disassembly
309 * should not be cached, this function should be overridden directly.
310 */
311 virtual const std::string &disassemble(Addr pc,
312 const SymbolTable *symtab = 0) const;
313
314 /**
315 * Print a separator separated list of this instruction's set flag
316 * names on the given stream.
317 */
318 void printFlags(std::ostream &outs, const std::string &separator) const;
319
320 /// Return name of machine instruction
321 std::string getName() { return mnemonic; }
322
323 protected:
324 template<typename T>
325 size_t
326 simpleAsBytes(void *buf, size_t max_size, const T &t)
327 {
328 size_t size = sizeof(T);
329 if (size <= max_size)
330 *reinterpret_cast<T *>(buf) = htole<T>(t);
331 return size;
332 }
333
334 public:
335 /**
336 * Instruction classes can override this function to return a
337 * a representation of themselves as a blob of bytes, generally assumed to
338 * be that instructions ExtMachInst.
339 *
340 * buf is a buffer to hold the bytes.
341 * max_size is the size allocated for that buffer by the caller.
342 * The return value is how much data was actually put into the buffer,
343 * zero if no data was put in the buffer, or the necessary size of the
344 * buffer if there wasn't enough space.
345 */
346 virtual size_t asBytes(void *buf, size_t max_size) { return 0; }
347};
348
349#endif // __CPU_STATIC_INST_HH__