regop.isa revision 6430:4c5671ecceda
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42// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
43// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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45// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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52// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
53//
54// Authors: Gabe Black
55
56//////////////////////////////////////////////////////////////////////////
57//
58// RegOp Microop templates
59//
60//////////////////////////////////////////////////////////////////////////
61
62def template MicroRegOpExecute {{
63        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
64                Trace::InstRecord *traceData) const
65        {
66            Fault fault = NoFault;
67
68            DPRINTF(X86, "The data size is %d\n", dataSize);
69            %(op_decl)s;
70            %(op_rd)s;
71
72            if(%(cond_check)s)
73            {
74                %(code)s;
75                %(flag_code)s;
76            }
77            else
78            {
79                %(else_code)s;
80            }
81
82            //Write the resulting state to the execution context
83            if(fault == NoFault)
84            {
85                %(op_wb)s;
86            }
87            return fault;
88        }
89}};
90
91def template MicroRegOpImmExecute {{
92        Fault %(class_name)s::execute(%(CPU_exec_context)s *xc,
93                Trace::InstRecord *traceData) const
94        {
95            Fault fault = NoFault;
96
97            %(op_decl)s;
98            %(op_rd)s;
99
100            if(%(cond_check)s)
101            {
102                %(code)s;
103                %(flag_code)s;
104            }
105            else
106            {
107                %(else_code)s;
108            }
109
110            //Write the resulting state to the execution context
111            if(fault == NoFault)
112            {
113                %(op_wb)s;
114            }
115            return fault;
116        }
117}};
118
119def template MicroRegOpDeclare {{
120    class %(class_name)s : public %(base_class)s
121    {
122      protected:
123        void buildMe();
124
125      public:
126        %(class_name)s(ExtMachInst _machInst,
127                const char * instMnem,
128                bool isMicro, bool isDelayed, bool isFirst, bool isLast,
129                InstRegIndex _src1, InstRegIndex _src2, InstRegIndex _dest,
130                uint8_t _dataSize, uint16_t _ext);
131
132        %(class_name)s(ExtMachInst _machInst,
133                const char * instMnem,
134                InstRegIndex _src1, InstRegIndex _src2, InstRegIndex _dest,
135                uint8_t _dataSize, uint16_t _ext);
136
137        %(BasicExecDeclare)s
138    };
139}};
140
141def template MicroRegOpImmDeclare {{
142
143    class %(class_name)s : public %(base_class)s
144    {
145      protected:
146        void buildMe();
147
148      public:
149        %(class_name)s(ExtMachInst _machInst,
150                const char * instMnem,
151                bool isMicro, bool isDelayed, bool isFirst, bool isLast,
152                InstRegIndex _src1, uint16_t _imm8, InstRegIndex _dest,
153                uint8_t _dataSize, uint16_t _ext);
154
155        %(class_name)s(ExtMachInst _machInst,
156                const char * instMnem,
157                InstRegIndex _src1, uint16_t _imm8, InstRegIndex _dest,
158                uint8_t _dataSize, uint16_t _ext);
159
160        %(BasicExecDeclare)s
161    };
162}};
163
164def template MicroRegOpConstructor {{
165
166    inline void %(class_name)s::buildMe()
167    {
168        %(constructor)s;
169    }
170
171    inline %(class_name)s::%(class_name)s(
172            ExtMachInst machInst, const char * instMnem,
173            InstRegIndex _src1, InstRegIndex _src2, InstRegIndex _dest,
174            uint8_t _dataSize, uint16_t _ext) :
175        %(base_class)s(machInst, "%(mnemonic)s", instMnem,
176                false, false, false, false,
177                _src1, _src2, _dest, _dataSize, _ext,
178                %(op_class)s)
179    {
180        buildMe();
181    }
182
183    inline %(class_name)s::%(class_name)s(
184            ExtMachInst machInst, const char * instMnem,
185            bool isMicro, bool isDelayed, bool isFirst, bool isLast,
186            InstRegIndex _src1, InstRegIndex _src2, InstRegIndex _dest,
187            uint8_t _dataSize, uint16_t _ext) :
188        %(base_class)s(machInst, "%(mnemonic)s", instMnem,
189                isMicro, isDelayed, isFirst, isLast,
190                _src1, _src2, _dest, _dataSize, _ext,
191                %(op_class)s)
192    {
193        buildMe();
194    }
195}};
196
197def template MicroRegOpImmConstructor {{
198
199    inline void %(class_name)s::buildMe()
200    {
201        %(constructor)s;
202    }
203
204    inline %(class_name)s::%(class_name)s(
205            ExtMachInst machInst, const char * instMnem,
206            InstRegIndex _src1, uint16_t _imm8, InstRegIndex _dest,
207            uint8_t _dataSize, uint16_t _ext) :
208        %(base_class)s(machInst, "%(mnemonic)s", instMnem,
209                false, false, false, false,
210                _src1, _imm8, _dest, _dataSize, _ext,
211                %(op_class)s)
212    {
213        buildMe();
214    }
215
216    inline %(class_name)s::%(class_name)s(
217            ExtMachInst machInst, const char * instMnem,
218            bool isMicro, bool isDelayed, bool isFirst, bool isLast,
219            InstRegIndex _src1, uint16_t _imm8, InstRegIndex _dest,
220            uint8_t _dataSize, uint16_t _ext) :
221        %(base_class)s(machInst, "%(mnemonic)s", instMnem,
222                isMicro, isDelayed, isFirst, isLast,
223                _src1, _imm8, _dest, _dataSize, _ext,
224                %(op_class)s)
225    {
226        buildMe();
227    }
228}};
229
230output header {{
231    void
232    divide(uint64_t dividend, uint64_t divisor,
233            uint64_t &quotient, uint64_t &remainder);
234
235    enum SegmentSelectorCheck {
236      SegNoCheck, SegCSCheck, SegCallGateCheck, SegIntGateCheck,
237      SegSoftIntGateCheck, SegSSCheck, SegIretCheck, SegIntCSCheck,
238      SegTRCheck, SegTSSCheck, SegInGDTCheck, SegLDTCheck
239    };
240
241    enum LongModeDescriptorType {
242        LDT64 = 2,
243        AvailableTSS64 = 9,
244        BusyTSS64 = 0xb,
245        CallGate64 = 0xc,
246        IntGate64 = 0xe,
247        TrapGate64 = 0xf
248    };
249}};
250
251output decoder {{
252    void
253    divide(uint64_t dividend, uint64_t divisor,
254            uint64_t &quotient, uint64_t &remainder)
255    {
256        //Check for divide by zero.
257        if (divisor == 0)
258            panic("Divide by zero!\\n");
259        //If the divisor is bigger than the dividend, don't do anything.
260        if (divisor <= dividend) {
261            //Shift the divisor so it's msb lines up with the dividend.
262            int dividendMsb = findMsbSet(dividend);
263            int divisorMsb = findMsbSet(divisor);
264            int shift = dividendMsb - divisorMsb;
265            divisor <<= shift;
266            //Compute what we'll add to the quotient if the divisor isn't
267            //now larger than the dividend.
268            uint64_t quotientBit = 1;
269            quotientBit <<= shift;
270            //If we need to step back a bit (no pun intended) because the
271            //divisor got too to large, do that here. This is the "or two"
272            //part of one or two bit division.
273            if (divisor > dividend) {
274                quotientBit >>= 1;
275                divisor >>= 1;
276            }
277            //Decrement the remainder and increment the quotient.
278            quotient += quotientBit;
279            remainder -= divisor;
280        }
281    }
282}};
283
284let {{
285    # Make these empty strings so that concatenating onto
286    # them will always work.
287    header_output = ""
288    decoder_output = ""
289    exec_output = ""
290
291    immTemplates = (
292            MicroRegOpImmDeclare,
293            MicroRegOpImmConstructor,
294            MicroRegOpImmExecute)
295
296    regTemplates = (
297            MicroRegOpDeclare,
298            MicroRegOpConstructor,
299            MicroRegOpExecute)
300
301    class RegOpMeta(type):
302        def buildCppClasses(self, name, Name, suffix, \
303                code, flag_code, cond_check, else_code):
304
305            # Globals to stick the output in
306            global header_output
307            global decoder_output
308            global exec_output
309
310            # Stick all the code together so it can be searched at once
311            allCode = "|".join((code, flag_code, cond_check, else_code))
312
313            # If op2 is used anywhere, make register and immediate versions
314            # of this code.
315            matcher = re.compile("(?<!\\w)(?P<prefix>s?)op2(?P<typeQual>\\.\\w+)?")
316            match = matcher.search(allCode)
317            if match:
318                typeQual = ""
319                if match.group("typeQual"):
320                    typeQual = match.group("typeQual")
321                src2_name = "%spsrc2%s" % (match.group("prefix"), typeQual)
322                self.buildCppClasses(name, Name, suffix,
323                        matcher.sub(src2_name, code),
324                        matcher.sub(src2_name, flag_code),
325                        matcher.sub(src2_name, cond_check),
326                        matcher.sub(src2_name, else_code))
327                self.buildCppClasses(name + "i", Name, suffix + "Imm",
328                        matcher.sub("imm8", code),
329                        matcher.sub("imm8", flag_code),
330                        matcher.sub("imm8", cond_check),
331                        matcher.sub("imm8", else_code))
332                return
333
334            # If there's something optional to do with flags, generate
335            # a version without it and fix up this version to use it.
336            if flag_code != "" or cond_check != "true":
337                self.buildCppClasses(name, Name, suffix,
338                        code, "", "true", else_code)
339                suffix = "Flags" + suffix
340
341            # If psrc1 or psrc2 is used, we need to actually insert code to
342            # compute it.
343            matcher = re.compile("(?<!\w)psrc1(?!\w)")
344            if matcher.search(allCode):
345                code = "uint64_t psrc1 = pick(SrcReg1, 0, dataSize);" + code
346            matcher = re.compile("(?<!\w)psrc2(?!\w)")
347            if matcher.search(allCode):
348                code = "uint64_t psrc2 = pick(SrcReg2, 1, dataSize);" + code
349            # Also make available versions which do sign extension
350            matcher = re.compile("(?<!\w)spsrc1(?!\w)")
351            if matcher.search(allCode):
352                code = "int64_t spsrc1 = signedPick(SrcReg1, 0, dataSize);" + code
353            matcher = re.compile("(?<!\w)spsrc2(?!\w)")
354            if matcher.search(allCode):
355                code = "int64_t spsrc2 = signedPick(SrcReg2, 1, dataSize);" + code
356
357            base = "X86ISA::RegOp"
358
359            # If imm8 shows up in the code, use the immediate templates, if
360            # not, hopefully the register ones will be correct.
361            templates = regTemplates
362            matcher = re.compile("(?<!\w)imm8(?!\w)")
363            if matcher.search(allCode):
364                base += "Imm"
365                templates = immTemplates
366
367            # Get everything ready for the substitution
368            iop = InstObjParams(name, Name + suffix, base,
369                    {"code" : code,
370                     "flag_code" : flag_code,
371                     "cond_check" : cond_check,
372                     "else_code" : else_code})
373
374            # Generate the actual code (finally!)
375            header_output += templates[0].subst(iop)
376            decoder_output += templates[1].subst(iop)
377            exec_output += templates[2].subst(iop)
378
379
380        def __new__(mcls, Name, bases, dict):
381            abstract = False
382            name = Name.lower()
383            if "abstract" in dict:
384                abstract = dict['abstract']
385                del dict['abstract']
386
387            cls = super(RegOpMeta, mcls).__new__(mcls, Name, bases, dict)
388            if not abstract:
389                cls.className = Name
390                cls.base_mnemonic = name
391                code = cls.code
392                flag_code = cls.flag_code
393                cond_check = cls.cond_check
394                else_code = cls.else_code
395
396                # Set up the C++ classes
397                mcls.buildCppClasses(cls, name, Name, "",
398                        code, flag_code, cond_check, else_code)
399
400                # Hook into the microassembler dict
401                global microopClasses
402                microopClasses[name] = cls
403
404                allCode = "|".join((code, flag_code, cond_check, else_code))
405
406                # If op2 is used anywhere, make register and immediate versions
407                # of this code.
408                matcher = re.compile("op2(?P<typeQual>\\.\\w+)?")
409                if matcher.search(allCode):
410                    microopClasses[name + 'i'] = cls
411            return cls
412
413
414    class RegOp(X86Microop):
415        __metaclass__ = RegOpMeta
416        # This class itself doesn't act as a microop
417        abstract = True
418
419        # Default template parameter values
420        flag_code = ""
421        cond_check = "true"
422        else_code = ";"
423
424        def __init__(self, dest, src1, op2, flags = None, dataSize = "env.dataSize"):
425            self.dest = dest
426            self.src1 = src1
427            self.op2 = op2
428            self.flags = flags
429            self.dataSize = dataSize
430            if flags is None:
431                self.ext = 0
432            else:
433                if not isinstance(flags, (list, tuple)):
434                    raise Exception, "flags must be a list or tuple of flags"
435                self.ext = " | ".join(flags)
436                self.className += "Flags"
437
438        def getAllocator(self, *microFlags):
439            className = self.className
440            if self.mnemonic == self.base_mnemonic + 'i':
441                className += "Imm"
442            allocator = '''new %(class_name)s(machInst, macrocodeBlock
443                    %(flags)s, %(src1)s, %(op2)s, %(dest)s,
444                    %(dataSize)s, %(ext)s)''' % {
445                "class_name" : className,
446                "flags" : self.microFlagsText(microFlags),
447                "src1" : self.src1, "op2" : self.op2,
448                "dest" : self.dest,
449                "dataSize" : self.dataSize,
450                "ext" : self.ext}
451            return allocator
452
453    class LogicRegOp(RegOp):
454        abstract = True
455        flag_code = '''
456            //Don't have genFlags handle the OF or CF bits
457            uint64_t mask = CFBit | ECFBit | OFBit;
458            ccFlagBits = genFlags(ccFlagBits, ext & ~mask, DestReg, psrc1, op2);
459            //If a logic microop wants to set these, it wants to set them to 0.
460            ccFlagBits &= ~(CFBit & ext);
461            ccFlagBits &= ~(ECFBit & ext);
462            ccFlagBits &= ~(OFBit & ext);
463        '''
464
465    class FlagRegOp(RegOp):
466        abstract = True
467        flag_code = \
468            "ccFlagBits = genFlags(ccFlagBits, ext, DestReg, psrc1, op2);"
469
470    class SubRegOp(RegOp):
471        abstract = True
472        flag_code = \
473            "ccFlagBits = genFlags(ccFlagBits, ext, DestReg, psrc1, ~op2, true);"
474
475    class CondRegOp(RegOp):
476        abstract = True
477        cond_check = "checkCondition(ccFlagBits, ext)"
478
479    class RdRegOp(RegOp):
480        abstract = True
481        def __init__(self, dest, src1=None, dataSize="env.dataSize"):
482            if not src1:
483                src1 = dest
484            super(RdRegOp, self).__init__(dest, src1, \
485                    "InstRegIndex(NUM_INTREGS)", None, dataSize)
486
487    class WrRegOp(RegOp):
488        abstract = True
489        def __init__(self, src1, src2, flags=None, dataSize="env.dataSize"):
490            super(WrRegOp, self).__init__("InstRegIndex(NUM_INTREGS)", \
491                    src1, src2, flags, dataSize)
492
493    class Add(FlagRegOp):
494        code = 'DestReg = merge(DestReg, psrc1 + op2, dataSize);'
495
496    class Or(LogicRegOp):
497        code = 'DestReg = merge(DestReg, psrc1 | op2, dataSize);'
498
499    class Adc(FlagRegOp):
500        code = '''
501            CCFlagBits flags = ccFlagBits;
502            DestReg = merge(DestReg, psrc1 + op2 + flags.cf, dataSize);
503            '''
504
505    class Sbb(SubRegOp):
506        code = '''
507            CCFlagBits flags = ccFlagBits;
508            DestReg = merge(DestReg, psrc1 - op2 - flags.cf, dataSize);
509            '''
510
511    class And(LogicRegOp):
512        code = 'DestReg = merge(DestReg, psrc1 & op2, dataSize)'
513
514    class Sub(SubRegOp):
515        code = 'DestReg = merge(DestReg, psrc1 - op2, dataSize)'
516
517    class Xor(LogicRegOp):
518        code = 'DestReg = merge(DestReg, psrc1 ^ op2, dataSize)'
519
520    class Mul1s(WrRegOp):
521        code = '''
522            ProdLow = psrc1 * op2;
523            int halfSize = (dataSize * 8) / 2;
524            uint64_t shifter = (1ULL << halfSize);
525            uint64_t hiResult;
526            uint64_t psrc1_h = psrc1 / shifter;
527            uint64_t psrc1_l = psrc1 & mask(halfSize);
528            uint64_t psrc2_h = op2 / shifter;
529            uint64_t psrc2_l = op2 & mask(halfSize);
530            hiResult = ((psrc1_l * psrc2_h + psrc1_h * psrc2_l +
531                        ((psrc1_l * psrc2_l) / shifter)) /shifter) +
532                       psrc1_h * psrc2_h;
533            if (spsrc1 < 0)
534                hiResult -= op2;
535            int64_t bigSop2 = sop2;
536            if (bigSop2 < 0)
537                hiResult -= psrc1;
538            ProdHi = hiResult;
539            '''
540
541    class Mul1u(WrRegOp):
542        code = '''
543            ProdLow = psrc1 * op2;
544            int halfSize = (dataSize * 8) / 2;
545            uint64_t shifter = (1ULL << halfSize);
546            uint64_t psrc1_h = psrc1 / shifter;
547            uint64_t psrc1_l = psrc1 & mask(halfSize);
548            uint64_t psrc2_h = op2 / shifter;
549            uint64_t psrc2_l = op2 & mask(halfSize);
550            ProdHi = ((psrc1_l * psrc2_h + psrc1_h * psrc2_l +
551                      ((psrc1_l * psrc2_l) / shifter)) / shifter) +
552                     psrc1_h * psrc2_h;
553            '''
554
555    class Mulel(RdRegOp):
556        code = 'DestReg = merge(SrcReg1, ProdLow, dataSize);'
557
558    class Muleh(RdRegOp):
559        def __init__(self, dest, src1=None, flags=None, dataSize="env.dataSize"):
560            if not src1:
561                src1 = dest
562            super(RdRegOp, self).__init__(dest, src1, \
563                    "InstRegIndex(NUM_INTREGS)", flags, dataSize)
564        code = 'DestReg = merge(SrcReg1, ProdHi, dataSize);'
565        flag_code = '''
566            if (ProdHi)
567                ccFlagBits = ccFlagBits | (ext & (CFBit | OFBit | ECFBit));
568            else
569                ccFlagBits = ccFlagBits & ~(ext & (CFBit | OFBit | ECFBit));
570        '''
571
572    # One or two bit divide
573    class Div1(WrRegOp):
574        code = '''
575            //These are temporaries so that modifying them later won't make
576            //the ISA parser think they're also sources.
577            uint64_t quotient = 0;
578            uint64_t remainder = psrc1;
579            //Similarly, this is a temporary so changing it doesn't make it
580            //a source.
581            uint64_t divisor = op2;
582            //This is a temporary just for consistency and clarity.
583            uint64_t dividend = remainder;
584            //Do the division.
585            divide(dividend, divisor, quotient, remainder);
586            //Record the final results.
587            Remainder = remainder;
588            Quotient = quotient;
589            Divisor = divisor;
590            '''
591
592    # Step divide
593    class Div2(RegOp):
594        code = '''
595            uint64_t dividend = Remainder;
596            uint64_t divisor = Divisor;
597            uint64_t quotient = Quotient;
598            uint64_t remainder = dividend;
599            int remaining = op2;
600            //If we overshot, do nothing. This lets us unrool division loops a
601            //little.
602            if (remaining) {
603                //Shift in bits from the low order portion of the dividend
604                while(dividend < divisor && remaining) {
605                    dividend = (dividend << 1) | bits(SrcReg1, remaining - 1);
606                    quotient <<= 1;
607                    remaining--;
608                }
609                remainder = dividend;
610                //Do the division.
611                divide(dividend, divisor, quotient, remainder);
612            }
613            //Keep track of how many bits there are still to pull in.
614            DestReg = merge(DestReg, remaining, dataSize);
615            //Record the final results
616            Remainder = remainder;
617            Quotient = quotient;
618        '''
619        flag_code = '''
620            if (DestReg == 0)
621                ccFlagBits = ccFlagBits | (ext & EZFBit);
622            else
623                ccFlagBits = ccFlagBits & ~(ext & EZFBit);
624        '''
625
626    class Divq(RdRegOp):
627        code = 'DestReg = merge(SrcReg1, Quotient, dataSize);'
628
629    class Divr(RdRegOp):
630        code = 'DestReg = merge(SrcReg1, Remainder, dataSize);'
631
632    class Mov(CondRegOp):
633        code = 'DestReg = merge(SrcReg1, op2, dataSize)'
634        else_code = 'DestReg=DestReg;'
635
636    # Shift instructions
637
638    class Sll(RegOp):
639        code = '''
640            uint8_t shiftAmt = (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
641            DestReg = merge(DestReg, psrc1 << shiftAmt, dataSize);
642            '''
643        flag_code = '''
644            // If the shift amount is zero, no flags should be modified.
645            if (shiftAmt) {
646                //Zero out any flags we might modify. This way we only have to
647                //worry about setting them.
648                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
649                int CFBits = 0;
650                //Figure out if we -would- set the CF bits if requested.
651                if (bits(SrcReg1, dataSize * 8 - shiftAmt))
652                    CFBits = 1;
653                //If some combination of the CF bits need to be set, set them.
654                if ((ext & (CFBit | ECFBit)) && CFBits)
655                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
656                //Figure out what the OF bit should be.
657                if ((ext & OFBit) && (CFBits ^ bits(DestReg, dataSize * 8 - 1)))
658                    ccFlagBits = ccFlagBits | OFBit;
659                //Use the regular mechanisms to calculate the other flags.
660                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
661                        DestReg, psrc1, op2);
662            }
663        '''
664
665    class Srl(RegOp):
666        code = '''
667            uint8_t shiftAmt = (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
668            // Because what happens to the bits shift -in- on a right shift
669            // is not defined in the C/C++ standard, we have to mask them out
670            // to be sure they're zero.
671            uint64_t logicalMask = mask(dataSize * 8 - shiftAmt);
672            DestReg = merge(DestReg, (psrc1 >> shiftAmt) & logicalMask, dataSize);
673            '''
674        flag_code = '''
675            // If the shift amount is zero, no flags should be modified.
676            if (shiftAmt) {
677                //Zero out any flags we might modify. This way we only have to
678                //worry about setting them.
679                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
680                //If some combination of the CF bits need to be set, set them.
681                if ((ext & (CFBit | ECFBit)) && bits(SrcReg1, shiftAmt - 1))
682                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
683                //Figure out what the OF bit should be.
684                if ((ext & OFBit) && bits(SrcReg1, dataSize * 8 - 1))
685                    ccFlagBits = ccFlagBits | OFBit;
686                //Use the regular mechanisms to calculate the other flags.
687                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
688                        DestReg, psrc1, op2);
689            }
690        '''
691
692    class Sra(RegOp):
693        code = '''
694            uint8_t shiftAmt = (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
695            // Because what happens to the bits shift -in- on a right shift
696            // is not defined in the C/C++ standard, we have to sign extend
697            // them manually to be sure.
698            uint64_t arithMask =
699                -bits(psrc1, dataSize * 8 - 1) << (dataSize * 8 - shiftAmt);
700            DestReg = merge(DestReg, (psrc1 >> shiftAmt) | arithMask, dataSize);
701            '''
702        flag_code = '''
703            // If the shift amount is zero, no flags should be modified.
704            if (shiftAmt) {
705                //Zero out any flags we might modify. This way we only have to
706                //worry about setting them.
707                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
708                //If some combination of the CF bits need to be set, set them.
709                if ((ext & (CFBit | ECFBit)) && bits(SrcReg1, shiftAmt - 1))
710                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
711                //Use the regular mechanisms to calculate the other flags.
712                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
713                        DestReg, psrc1, op2);
714            }
715        '''
716
717    class Ror(RegOp):
718        code = '''
719            uint8_t shiftAmt =
720                (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
721            if(shiftAmt)
722            {
723                uint64_t top = psrc1 << (dataSize * 8 - shiftAmt);
724                uint64_t bottom = bits(psrc1, dataSize * 8, shiftAmt);
725                DestReg = merge(DestReg, top | bottom, dataSize);
726            }
727            else
728                DestReg = DestReg;
729            '''
730        flag_code = '''
731            // If the shift amount is zero, no flags should be modified.
732            if (shiftAmt) {
733                //Zero out any flags we might modify. This way we only have to
734                //worry about setting them.
735                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
736                //Find the most and second most significant bits of the result.
737                int msb = bits(DestReg, dataSize * 8 - 1);
738                int smsb = bits(DestReg, dataSize * 8 - 2);
739                //If some combination of the CF bits need to be set, set them.
740                if ((ext & (CFBit | ECFBit)) && msb)
741                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
742                //Figure out what the OF bit should be.
743                if ((ext & OFBit) && (msb ^ smsb))
744                    ccFlagBits = ccFlagBits | OFBit;
745                //Use the regular mechanisms to calculate the other flags.
746                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
747                        DestReg, psrc1, op2);
748            }
749        '''
750
751    class Rcr(RegOp):
752        code = '''
753            uint8_t shiftAmt =
754                (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
755            if(shiftAmt)
756            {
757                CCFlagBits flags = ccFlagBits;
758                uint64_t top = flags.cf << (dataSize * 8 - shiftAmt);
759                if(shiftAmt > 1)
760                    top |= psrc1 << (dataSize * 8 - shiftAmt - 1);
761                uint64_t bottom = bits(psrc1, dataSize * 8, shiftAmt);
762                DestReg = merge(DestReg, top | bottom, dataSize);
763            }
764            else
765                DestReg = DestReg;
766            '''
767        flag_code = '''
768            // If the shift amount is zero, no flags should be modified.
769            if (shiftAmt) {
770                //Zero out any flags we might modify. This way we only have to
771                //worry about setting them.
772                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
773                //Figure out what the OF bit should be.
774                if ((ext & OFBit) && ((ccFlagBits & CFBit) ^
775                                      bits(SrcReg1, dataSize * 8 - 1)))
776                    ccFlagBits = ccFlagBits | OFBit;
777                //If some combination of the CF bits need to be set, set them.
778                if ((ext & (CFBit | ECFBit)) && bits(SrcReg1, shiftAmt - 1))
779                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
780                //Use the regular mechanisms to calculate the other flags.
781                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
782                        DestReg, psrc1, op2);
783            }
784        '''
785
786    class Rol(RegOp):
787        code = '''
788            uint8_t shiftAmt =
789                (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
790            if(shiftAmt)
791            {
792                uint64_t top = psrc1 << shiftAmt;
793                uint64_t bottom =
794                    bits(psrc1, dataSize * 8 - 1, dataSize * 8 - shiftAmt);
795                DestReg = merge(DestReg, top | bottom, dataSize);
796            }
797            else
798                DestReg = DestReg;
799            '''
800        flag_code = '''
801            // If the shift amount is zero, no flags should be modified.
802            if (shiftAmt) {
803                //Zero out any flags we might modify. This way we only have to
804                //worry about setting them.
805                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
806                //The CF bits, if set, would be set to the lsb of the result.
807                int lsb = DestReg & 0x1;
808                int msb = bits(DestReg, dataSize * 8 - 1);
809                //If some combination of the CF bits need to be set, set them.
810                if ((ext & (CFBit | ECFBit)) && lsb)
811                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
812                //Figure out what the OF bit should be.
813                if ((ext & OFBit) && (msb ^ lsb))
814                    ccFlagBits = ccFlagBits | OFBit;
815                //Use the regular mechanisms to calculate the other flags.
816                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
817                        DestReg, psrc1, op2);
818            }
819        '''
820
821    class Rcl(RegOp):
822        code = '''
823            uint8_t shiftAmt =
824                (op2 & ((dataSize == 8) ? mask(6) : mask(5)));
825            if(shiftAmt)
826            {
827                CCFlagBits flags = ccFlagBits;
828                uint64_t top = psrc1 << shiftAmt;
829                uint64_t bottom = flags.cf << (shiftAmt - 1);
830                if(shiftAmt > 1)
831                    bottom |=
832                        bits(psrc1, dataSize * 8 - 1,
833                                   dataSize * 8 - shiftAmt + 1);
834                DestReg = merge(DestReg, top | bottom, dataSize);
835            }
836            else
837                DestReg = DestReg;
838            '''
839        flag_code = '''
840            // If the shift amount is zero, no flags should be modified.
841            if (shiftAmt) {
842                //Zero out any flags we might modify. This way we only have to
843                //worry about setting them.
844                ccFlagBits = ccFlagBits & ~(ext & (CFBit | ECFBit | OFBit));
845                int msb = bits(DestReg, dataSize * 8 - 1);
846                int CFBits = bits(SrcReg1, dataSize * 8 - shiftAmt);
847                //If some combination of the CF bits need to be set, set them.
848                if ((ext & (CFBit | ECFBit)) && CFBits)
849                    ccFlagBits = ccFlagBits | (ext & (CFBit | ECFBit));
850                //Figure out what the OF bit should be.
851                if ((ext & OFBit) && (msb ^ CFBits))
852                    ccFlagBits = ccFlagBits | OFBit;
853                //Use the regular mechanisms to calculate the other flags.
854                ccFlagBits = genFlags(ccFlagBits, ext & ~(CFBit | ECFBit | OFBit),
855                        DestReg, psrc1, op2);
856            }
857        '''
858
859    class Wrip(WrRegOp, CondRegOp):
860        code = 'RIP = psrc1 + sop2 + CSBase'
861        else_code="RIP = RIP;"
862
863    class Wruflags(WrRegOp):
864        code = 'ccFlagBits = psrc1 ^ op2'
865
866    class Wrflags(WrRegOp):
867        code = '''
868            MiscReg newFlags = psrc1 ^ op2;
869            MiscReg userFlagMask = 0xDD5;
870            // Get only the user flags
871            ccFlagBits = newFlags & userFlagMask;
872            // Get everything else
873            nccFlagBits = newFlags & ~userFlagMask;
874        '''
875
876    class Rdip(RdRegOp):
877        code = 'DestReg = RIP - CSBase'
878
879    class Ruflags(RdRegOp):
880        code = 'DestReg = ccFlagBits'
881
882    class Rflags(RdRegOp):
883        code = 'DestReg = ccFlagBits | nccFlagBits'
884
885    class Ruflag(RegOp):
886        code = '''
887            int flag = bits(ccFlagBits, imm8);
888            DestReg = merge(DestReg, flag, dataSize);
889            ccFlagBits = (flag == 0) ? (ccFlagBits | EZFBit) :
890                                       (ccFlagBits & ~EZFBit);
891            '''
892        def __init__(self, dest, imm, flags=None, \
893                dataSize="env.dataSize"):
894            super(Ruflag, self).__init__(dest, \
895                    "InstRegIndex(NUM_INTREGS)", imm, flags, dataSize)
896
897    class Rflag(RegOp):
898        code = '''
899            MiscReg flagMask = 0x3F7FDD5;
900            MiscReg flags = (nccFlagBits | ccFlagBits) & flagMask;
901            int flag = bits(flags, imm8);
902            DestReg = merge(DestReg, flag, dataSize);
903            ccFlagBits = (flag == 0) ? (ccFlagBits | EZFBit) :
904                                       (ccFlagBits & ~EZFBit);
905            '''
906        def __init__(self, dest, imm, flags=None, \
907                dataSize="env.dataSize"):
908            super(Rflag, self).__init__(dest, \
909                    "InstRegIndex(NUM_INTREGS)", imm, flags, dataSize)
910
911    class Sext(RegOp):
912        code = '''
913            IntReg val = psrc1;
914            // Mask the bit position so that it wraps.
915            int bitPos = op2 & (dataSize * 8 - 1);
916            int sign_bit = bits(val, bitPos, bitPos);
917            uint64_t maskVal = mask(bitPos+1);
918            val = sign_bit ? (val | ~maskVal) : (val & maskVal);
919            DestReg = merge(DestReg, val, dataSize);
920            '''
921        flag_code = '''
922            if (!sign_bit)
923                ccFlagBits = ccFlagBits &
924                    ~(ext & (CFBit | ECFBit | ZFBit | EZFBit));
925            else
926                ccFlagBits = ccFlagBits |
927                    (ext & (CFBit | ECFBit | ZFBit | EZFBit));
928            '''
929
930    class Zext(RegOp):
931        code = 'DestReg = merge(DestReg, bits(psrc1, op2, 0), dataSize);'
932
933    class Rddr(RegOp):
934        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
935            super(Rddr, self).__init__(dest, \
936                    src1, "InstRegIndex(NUM_INTREGS)", flags, dataSize)
937        code = '''
938            CR4 cr4 = CR4Op;
939            DR7 dr7 = DR7Op;
940            if ((cr4.de == 1 && (src1 == 4 || src1 == 5)) || src1 >= 8) {
941                fault = new InvalidOpcode();
942            } else if (dr7.gd) {
943                fault = new DebugException();
944            } else {
945                DestReg = merge(DestReg, DebugSrc1, dataSize);
946            }
947        '''
948
949    class Wrdr(RegOp):
950        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
951            super(Wrdr, self).__init__(dest, \
952                    src1, "InstRegIndex(NUM_INTREGS)", flags, dataSize)
953        code = '''
954            CR4 cr4 = CR4Op;
955            DR7 dr7 = DR7Op;
956            if ((cr4.de == 1 && (dest == 4 || dest == 5)) || dest >= 8) {
957                fault = new InvalidOpcode();
958            } else if ((dest == 6 || dest == 7) && bits(psrc1, 63, 32) &&
959                    machInst.mode.mode == LongMode) {
960                fault = new GeneralProtection(0);
961            } else if (dr7.gd) {
962                fault = new DebugException();
963            } else {
964                DebugDest = psrc1;
965            }
966        '''
967
968    class Rdcr(RegOp):
969        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
970            super(Rdcr, self).__init__(dest, \
971                    src1, "InstRegIndex(NUM_INTREGS)", flags, dataSize)
972        code = '''
973            if (src1 == 1 || (src1 > 4 && src1 < 8) || (src1 > 8)) {
974                fault = new InvalidOpcode();
975            } else {
976                DestReg = merge(DestReg, ControlSrc1, dataSize);
977            }
978        '''
979
980    class Wrcr(RegOp):
981        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
982            super(Wrcr, self).__init__(dest, \
983                    src1, "InstRegIndex(NUM_INTREGS)", flags, dataSize)
984        code = '''
985            if (dest == 1 || (dest > 4 && dest < 8) || (dest > 8)) {
986                fault = new InvalidOpcode();
987            } else {
988                // There are *s in the line below so it doesn't confuse the
989                // parser. They may be unnecessary.
990                //Mis*cReg old*Val = pick(Cont*rolDest, 0, dat*aSize);
991                MiscReg newVal = psrc1;
992
993                // Check for any modifications that would cause a fault.
994                switch(dest) {
995                  case 0:
996                    {
997                        Efer efer = EferOp;
998                        CR0 cr0 = newVal;
999                        CR4 oldCr4 = CR4Op;
1000                        if (bits(newVal, 63, 32) ||
1001                                (!cr0.pe && cr0.pg) ||
1002                                (!cr0.cd && cr0.nw) ||
1003                                (cr0.pg && efer.lme && !oldCr4.pae))
1004                            fault = new GeneralProtection(0);
1005                    }
1006                    break;
1007                  case 2:
1008                    break;
1009                  case 3:
1010                    break;
1011                  case 4:
1012                    {
1013                        CR4 cr4 = newVal;
1014                        // PAE can't be disabled in long mode.
1015                        if (bits(newVal, 63, 11) ||
1016                                (machInst.mode.mode == LongMode && !cr4.pae))
1017                            fault = new GeneralProtection(0);
1018                    }
1019                    break;
1020                  case 8:
1021                    {
1022                        if (bits(newVal, 63, 4))
1023                            fault = new GeneralProtection(0);
1024                    }
1025                  default:
1026                    panic("Unrecognized control register %d.\\n", dest);
1027                }
1028                ControlDest = newVal;
1029            }
1030            '''
1031
1032    # Microops for manipulating segmentation registers
1033    class SegOp(CondRegOp):
1034        abstract = True
1035        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
1036            super(SegOp, self).__init__(dest, \
1037                    src1, "InstRegIndex(NUM_INTREGS)", flags, dataSize)
1038
1039    class Wrbase(SegOp):
1040        code = '''
1041            SegBaseDest = psrc1;
1042        '''
1043
1044    class Wrlimit(SegOp):
1045        code = '''
1046            SegLimitDest = psrc1;
1047        '''
1048
1049    class Wrsel(SegOp):
1050        code = '''
1051            SegSelDest = psrc1;
1052        '''
1053
1054    class WrAttr(SegOp):
1055        code = '''
1056            SegAttrDest = psrc1;
1057        '''
1058
1059    class Rdbase(SegOp):
1060        code = '''
1061            DestReg = merge(DestReg, SegBaseSrc1, dataSize);
1062        '''
1063
1064    class Rdlimit(SegOp):
1065        code = '''
1066            DestReg = merge(DestReg, SegLimitSrc1, dataSize);
1067        '''
1068
1069    class RdAttr(SegOp):
1070        code = '''
1071            DestReg = merge(DestReg, SegAttrSrc1, dataSize);
1072        '''
1073
1074    class Rdsel(SegOp):
1075        code = '''
1076            DestReg = merge(DestReg, SegSelSrc1, dataSize);
1077        '''
1078
1079    class Rdval(RegOp):
1080        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
1081            super(Rdval, self).__init__(dest, src1, \
1082                    "InstRegIndex(NUM_INTREGS)", flags, dataSize)
1083        code = '''
1084            DestReg = MiscRegSrc1;
1085        '''
1086
1087    class Wrval(RegOp):
1088        def __init__(self, dest, src1, flags=None, dataSize="env.dataSize"):
1089            super(Wrval, self).__init__(dest, src1, \
1090                    "InstRegIndex(NUM_INTREGS)", flags, dataSize)
1091        code = '''
1092            MiscRegDest = SrcReg1;
1093        '''
1094
1095    class Chks(RegOp):
1096        def __init__(self, dest, src1, src2=0,
1097                flags=None, dataSize="env.dataSize"):
1098            super(Chks, self).__init__(dest,
1099                    src1, src2, flags, dataSize)
1100        code = '''
1101            // The selector is in source 1 and can be at most 16 bits.
1102            SegSelector selector = DestReg;
1103            SegDescriptor desc = SrcReg1;
1104            HandyM5Reg m5reg = M5Reg;
1105
1106            switch (imm8)
1107            {
1108              case SegNoCheck:
1109                break;
1110              case SegCSCheck:
1111                // Make sure it's the right type
1112                if (desc.s == 0 || desc.type.codeOrData != 1) {
1113                    fault = new GeneralProtection(0);
1114                } else if (m5reg.cpl != desc.dpl) {
1115                    fault = new GeneralProtection(0);
1116                }
1117                break;
1118              case SegCallGateCheck:
1119                panic("CS checks for far calls/jumps through call gates"
1120                        "not implemented.\\n");
1121                break;
1122              case SegSoftIntGateCheck:
1123                // Check permissions.
1124                if (desc.dpl < m5reg.cpl) {
1125                    fault = new GeneralProtection(selector);
1126                    break;
1127                }
1128                // Fall through on purpose
1129              case SegIntGateCheck:
1130                // Make sure the gate's the right type.
1131                if ((m5reg.mode == LongMode && (desc.type & 0xe) != 0xe) ||
1132                        ((desc.type & 0x6) != 0x6)) {
1133                    fault = new GeneralProtection(0);
1134                }
1135                break;
1136              case SegSSCheck:
1137                if (selector.si || selector.ti) {
1138                    if (!desc.p) {
1139                        fault = new StackFault(selector);
1140                    }
1141                } else {
1142                    if ((m5reg.submode != SixtyFourBitMode ||
1143                                m5reg.cpl == 3) ||
1144                            !(desc.s == 1 &&
1145                            desc.type.codeOrData == 0 && desc.type.w) ||
1146                            (desc.dpl != m5reg.cpl) ||
1147                            (selector.rpl != m5reg.cpl)) {
1148                        fault = new GeneralProtection(selector);
1149                    }
1150                }
1151                break;
1152              case SegIretCheck:
1153                {
1154                    if ((!selector.si && !selector.ti) ||
1155                            (selector.rpl < m5reg.cpl) ||
1156                            !(desc.s == 1 && desc.type.codeOrData == 1) ||
1157                            (!desc.type.c && desc.dpl != selector.rpl) ||
1158                            (desc.type.c && desc.dpl > selector.rpl)) {
1159                        fault = new GeneralProtection(selector);
1160                    } else if (!desc.p) {
1161                        fault = new SegmentNotPresent(selector);
1162                    }
1163                    break;
1164                }
1165              case SegIntCSCheck:
1166                if (m5reg.mode == LongMode) {
1167                    if (desc.l != 1 || desc.d != 0) {
1168                        fault = new GeneralProtection(selector);
1169                    }
1170                } else {
1171                    panic("Interrupt CS checks not implemented "
1172                            "in legacy mode.\\n");
1173                }
1174                break;
1175              case SegTRCheck:
1176                if (!selector.si || selector.ti) {
1177                    fault = new GeneralProtection(selector);
1178                }
1179                break;
1180              case SegTSSCheck:
1181                if (!desc.p) {
1182                    fault = new SegmentNotPresent(selector);
1183                } else if (!(desc.type == 0x9 ||
1184                        (desc.type == 1 &&
1185                         m5reg.mode != LongMode))) {
1186                    fault = new GeneralProtection(selector);
1187                }
1188                break;
1189              case SegInGDTCheck:
1190                if (selector.ti) {
1191                    fault = new GeneralProtection(selector);
1192                }
1193                break;
1194              case SegLDTCheck:
1195                if (!desc.p) {
1196                    fault = new SegmentNotPresent(selector);
1197                } else if (desc.type != 0x2) {
1198                    fault = new GeneralProtection(selector);
1199                }
1200                break;
1201              default:
1202                panic("Undefined segment check type.\\n");
1203            }
1204        '''
1205        flag_code = '''
1206            // Check for a NULL selector and set ZF,EZF appropriately.
1207            ccFlagBits = ccFlagBits & ~(ext & (ZFBit | EZFBit));
1208            if (!selector.si && !selector.ti)
1209                ccFlagBits = ccFlagBits | (ext & (ZFBit | EZFBit));
1210        '''
1211
1212    class Wrdh(RegOp):
1213        code = '''
1214            SegDescriptor desc = SrcReg1;
1215
1216            uint64_t target = bits(SrcReg2, 31, 0) << 32;
1217            switch(desc.type) {
1218              case LDT64:
1219              case AvailableTSS64:
1220              case BusyTSS64:
1221                replaceBits(target, 23, 0, desc.baseLow);
1222                replaceBits(target, 31, 24, desc.baseHigh);
1223                break;
1224              case CallGate64:
1225              case IntGate64:
1226              case TrapGate64:
1227                replaceBits(target, 15, 0, bits(desc, 15, 0));
1228                replaceBits(target, 31, 16, bits(desc, 63, 48));
1229                break;
1230              default:
1231                panic("Wrdh used with wrong descriptor type!\\n");
1232            }
1233            DestReg = target;
1234        '''
1235
1236    class Wrtsc(WrRegOp):
1237        code = '''
1238            TscOp = psrc1;
1239        '''
1240
1241    class Rdtsc(RdRegOp):
1242        code = '''
1243            DestReg = TscOp;
1244        '''
1245
1246    class Rdm5reg(RdRegOp):
1247        code = '''
1248            DestReg = M5Reg;
1249        '''
1250
1251    class Wrdl(RegOp):
1252        code = '''
1253            SegDescriptor desc = SrcReg1;
1254            SegSelector selector = SrcReg2;
1255            if (selector.si || selector.ti) {
1256                if (!desc.p)
1257                    panic("Segment not present.\\n");
1258                SegAttr attr = 0;
1259                attr.dpl = desc.dpl;
1260                attr.unusable = 0;
1261                attr.defaultSize = desc.d;
1262                attr.longMode = desc.l;
1263                attr.avl = desc.avl;
1264                attr.granularity = desc.g;
1265                attr.present = desc.p;
1266                attr.system = desc.s;
1267                attr.type = desc.type;
1268                if (!desc.s) {
1269                    // The expand down bit happens to be set for gates.
1270                    if (desc.type.e) {
1271                        panic("Gate descriptor encountered.\\n");
1272                    }
1273                    attr.readable = 1;
1274                    attr.writable = 1;
1275                    attr.expandDown = 0;
1276                } else {
1277                    if (desc.type.codeOrData) {
1278                        attr.expandDown = 0;
1279                        attr.readable = desc.type.r;
1280                        attr.writable = 0;
1281                    } else {
1282                        attr.expandDown = desc.type.e;
1283                        attr.readable = 1;
1284                        attr.writable = desc.type.w;
1285                    }
1286                }
1287                Addr base = desc.baseLow | (desc.baseHigh << 24);
1288                Addr limit = desc.limitLow | (desc.limitHigh << 16);
1289                if (desc.g)
1290                    limit = (limit << 12) | mask(12);
1291                SegBaseDest = base;
1292                SegLimitDest = limit;
1293                SegAttrDest = attr;
1294            } else {
1295                SegBaseDest = SegBaseDest;
1296                SegLimitDest = SegLimitDest;
1297                SegAttrDest = SegAttrDest;
1298            }
1299        '''
1300}};
1301