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MCRegisterInfo.h
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1 //===- MC/MCRegisterInfo.h - Target Register Description --------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file describes an abstract interface used to get information about a
11 // target machines register file. This information is used for a variety of
12 // purposed, especially register allocation.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_MC_MCREGISTERINFO_H
17 #define LLVM_MC_MCREGISTERINFO_H
18 
19 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/MC/LaneBitmask.h"
22 #include <cassert>
23 #include <cstdint>
24 #include <utility>
25 
26 namespace llvm {
27 
28 /// An unsigned integer type large enough to represent all physical registers,
29 /// but not necessarily virtual registers.
30 using MCPhysReg = uint16_t;
31 
32 /// MCRegisterClass - Base class of TargetRegisterClass.
34 public:
35  using iterator = const MCPhysReg*;
36  using const_iterator = const MCPhysReg*;
37 
39  const uint8_t *const RegSet;
41  const uint16_t RegsSize;
42  const uint16_t RegSetSize;
43  const uint16_t ID;
44  const uint16_t PhysRegSize;
45  const int8_t CopyCost;
46  const bool Allocatable;
47 
48  /// getID() - Return the register class ID number.
49  ///
50  unsigned getID() const { return ID; }
51 
52  /// begin/end - Return all of the registers in this class.
53  ///
54  iterator begin() const { return RegsBegin; }
55  iterator end() const { return RegsBegin + RegsSize; }
56 
57  /// getNumRegs - Return the number of registers in this class.
58  ///
59  unsigned getNumRegs() const { return RegsSize; }
60 
61  /// getRegister - Return the specified register in the class.
62  ///
63  unsigned getRegister(unsigned i) const {
64  assert(i < getNumRegs() && "Register number out of range!");
65  return RegsBegin[i];
66  }
67 
68  /// contains - Return true if the specified register is included in this
69  /// register class. This does not include virtual registers.
70  bool contains(unsigned Reg) const {
71  unsigned InByte = Reg % 8;
72  unsigned Byte = Reg / 8;
73  if (Byte >= RegSetSize)
74  return false;
75  return (RegSet[Byte] & (1 << InByte)) != 0;
76  }
77 
78  /// contains - Return true if both registers are in this class.
79  bool contains(unsigned Reg1, unsigned Reg2) const {
80  return contains(Reg1) && contains(Reg2);
81  }
82 
83  /// Return the size of the physical register in bytes.
84  unsigned getPhysRegSize() const { return PhysRegSize; }
85  /// Temporary function to allow out-of-tree targets to switch.
86  unsigned getSize() const { return getPhysRegSize(); }
87 
88  /// getCopyCost - Return the cost of copying a value between two registers in
89  /// this class. A negative number means the register class is very expensive
90  /// to copy e.g. status flag register classes.
91  int getCopyCost() const { return CopyCost; }
92 
93  /// isAllocatable - Return true if this register class may be used to create
94  /// virtual registers.
95  bool isAllocatable() const { return Allocatable; }
96 };
97 
98 /// MCRegisterDesc - This record contains information about a particular
99 /// register. The SubRegs field is a zero terminated array of registers that
100 /// are sub-registers of the specific register, e.g. AL, AH are sub-registers
101 /// of AX. The SuperRegs field is a zero terminated array of registers that are
102 /// super-registers of the specific register, e.g. RAX, EAX, are
103 /// super-registers of AX.
104 ///
106  uint32_t Name; // Printable name for the reg (for debugging)
107  uint32_t SubRegs; // Sub-register set, described above
108  uint32_t SuperRegs; // Super-register set, described above
109 
110  // Offset into MCRI::SubRegIndices of a list of sub-register indices for each
111  // sub-register in SubRegs.
113 
114  // RegUnits - Points to the list of register units. The low 4 bits holds the
115  // Scale, the high bits hold an offset into DiffLists. See MCRegUnitIterator.
117 
118  /// Index into list with lane mask sequences. The sequence contains a lanemask
119  /// for every register unit.
121 };
122 
123 /// MCRegisterInfo base class - We assume that the target defines a static
124 /// array of MCRegisterDesc objects that represent all of the machine
125 /// registers that the target has. As such, we simply have to track a pointer
126 /// to this array so that we can turn register number into a register
127 /// descriptor.
128 ///
129 /// Note this class is designed to be a base class of TargetRegisterInfo, which
130 /// is the interface used by codegen. However, specific targets *should never*
131 /// specialize this class. MCRegisterInfo should only contain getters to access
132 /// TableGen generated physical register data. It must not be extended with
133 /// virtual methods.
134 ///
136 public:
138 
139  /// DwarfLLVMRegPair - Emitted by tablegen so Dwarf<->LLVM reg mappings can be
140  /// performed with a binary search.
142  unsigned FromReg;
143  unsigned ToReg;
144 
145  bool operator<(DwarfLLVMRegPair RHS) const { return FromReg < RHS.FromReg; }
146  };
147 
148  /// SubRegCoveredBits - Emitted by tablegen: bit range covered by a subreg
149  /// index, -1 in any being invalid.
151  uint16_t Offset;
152  uint16_t Size;
153  };
154 
155 private:
156  const MCRegisterDesc *Desc; // Pointer to the descriptor array
157  unsigned NumRegs; // Number of entries in the array
158  unsigned RAReg; // Return address register
159  unsigned PCReg; // Program counter register
160  const MCRegisterClass *Classes; // Pointer to the regclass array
161  unsigned NumClasses; // Number of entries in the array
162  unsigned NumRegUnits; // Number of regunits.
163  const MCPhysReg (*RegUnitRoots)[2]; // Pointer to regunit root table.
164  const MCPhysReg *DiffLists; // Pointer to the difflists array
165  const LaneBitmask *RegUnitMaskSequences; // Pointer to lane mask sequences
166  // for register units.
167  const char *RegStrings; // Pointer to the string table.
168  const char *RegClassStrings; // Pointer to the class strings.
169  const uint16_t *SubRegIndices; // Pointer to the subreg lookup
170  // array.
171  const SubRegCoveredBits *SubRegIdxRanges; // Pointer to the subreg covered
172  // bit ranges array.
173  unsigned NumSubRegIndices; // Number of subreg indices.
174  const uint16_t *RegEncodingTable; // Pointer to array of register
175  // encodings.
176 
177  unsigned L2DwarfRegsSize;
178  unsigned EHL2DwarfRegsSize;
179  unsigned Dwarf2LRegsSize;
180  unsigned EHDwarf2LRegsSize;
181  const DwarfLLVMRegPair *L2DwarfRegs; // LLVM to Dwarf regs mapping
182  const DwarfLLVMRegPair *EHL2DwarfRegs; // LLVM to Dwarf regs mapping EH
183  const DwarfLLVMRegPair *Dwarf2LRegs; // Dwarf to LLVM regs mapping
184  const DwarfLLVMRegPair *EHDwarf2LRegs; // Dwarf to LLVM regs mapping EH
185  DenseMap<unsigned, int> L2SEHRegs; // LLVM to SEH regs mapping
186  DenseMap<unsigned, int> L2CVRegs; // LLVM to CV regs mapping
187 
188 public:
189  /// DiffListIterator - Base iterator class that can traverse the
190  /// differentially encoded register and regunit lists in DiffLists.
191  /// Don't use this class directly, use one of the specialized sub-classes
192  /// defined below.
194  uint16_t Val = 0;
195  const MCPhysReg *List = nullptr;
196 
197  protected:
198  /// Create an invalid iterator. Call init() to point to something useful.
199  DiffListIterator() = default;
200 
201  /// init - Point the iterator to InitVal, decoding subsequent values from
202  /// DiffList. The iterator will initially point to InitVal, sub-classes are
203  /// responsible for skipping the seed value if it is not part of the list.
204  void init(MCPhysReg InitVal, const MCPhysReg *DiffList) {
205  Val = InitVal;
206  List = DiffList;
207  }
208 
209  /// advance - Move to the next list position, return the applied
210  /// differential. This function does not detect the end of the list, that
211  /// is the caller's responsibility (by checking for a 0 return value).
212  unsigned advance() {
213  assert(isValid() && "Cannot move off the end of the list.");
214  MCPhysReg D = *List++;
215  Val += D;
216  return D;
217  }
218 
219  public:
220  /// isValid - returns true if this iterator is not yet at the end.
221  bool isValid() const { return List; }
222 
223  /// Dereference the iterator to get the value at the current position.
224  unsigned operator*() const { return Val; }
225 
226  /// Pre-increment to move to the next position.
227  void operator++() {
228  // The end of the list is encoded as a 0 differential.
229  if (!advance())
230  List = nullptr;
231  }
232  };
233 
234  // These iterators are allowed to sub-class DiffListIterator and access
235  // internal list pointers.
236  friend class MCSubRegIterator;
237  friend class MCSubRegIndexIterator;
238  friend class MCSuperRegIterator;
239  friend class MCRegUnitIterator;
240  friend class MCRegUnitMaskIterator;
241  friend class MCRegUnitRootIterator;
242 
243  /// \brief Initialize MCRegisterInfo, called by TableGen
244  /// auto-generated routines. *DO NOT USE*.
245  void InitMCRegisterInfo(const MCRegisterDesc *D, unsigned NR, unsigned RA,
246  unsigned PC,
247  const MCRegisterClass *C, unsigned NC,
248  const MCPhysReg (*RURoots)[2],
249  unsigned NRU,
250  const MCPhysReg *DL,
251  const LaneBitmask *RUMS,
252  const char *Strings,
253  const char *ClassStrings,
254  const uint16_t *SubIndices,
255  unsigned NumIndices,
256  const SubRegCoveredBits *SubIdxRanges,
257  const uint16_t *RET) {
258  Desc = D;
259  NumRegs = NR;
260  RAReg = RA;
261  PCReg = PC;
262  Classes = C;
263  DiffLists = DL;
264  RegUnitMaskSequences = RUMS;
265  RegStrings = Strings;
266  RegClassStrings = ClassStrings;
267  NumClasses = NC;
268  RegUnitRoots = RURoots;
269  NumRegUnits = NRU;
270  SubRegIndices = SubIndices;
271  NumSubRegIndices = NumIndices;
272  SubRegIdxRanges = SubIdxRanges;
273  RegEncodingTable = RET;
274 
275  // Initialize DWARF register mapping variables
276  EHL2DwarfRegs = nullptr;
277  EHL2DwarfRegsSize = 0;
278  L2DwarfRegs = nullptr;
279  L2DwarfRegsSize = 0;
280  EHDwarf2LRegs = nullptr;
281  EHDwarf2LRegsSize = 0;
282  Dwarf2LRegs = nullptr;
283  Dwarf2LRegsSize = 0;
284  }
285 
286  /// \brief Used to initialize LLVM register to Dwarf
287  /// register number mapping. Called by TableGen auto-generated routines.
288  /// *DO NOT USE*.
289  void mapLLVMRegsToDwarfRegs(const DwarfLLVMRegPair *Map, unsigned Size,
290  bool isEH) {
291  if (isEH) {
292  EHL2DwarfRegs = Map;
293  EHL2DwarfRegsSize = Size;
294  } else {
295  L2DwarfRegs = Map;
296  L2DwarfRegsSize = Size;
297  }
298  }
299 
300  /// \brief Used to initialize Dwarf register to LLVM
301  /// register number mapping. Called by TableGen auto-generated routines.
302  /// *DO NOT USE*.
303  void mapDwarfRegsToLLVMRegs(const DwarfLLVMRegPair *Map, unsigned Size,
304  bool isEH) {
305  if (isEH) {
306  EHDwarf2LRegs = Map;
307  EHDwarf2LRegsSize = Size;
308  } else {
309  Dwarf2LRegs = Map;
310  Dwarf2LRegsSize = Size;
311  }
312  }
313 
314  /// mapLLVMRegToSEHReg - Used to initialize LLVM register to SEH register
315  /// number mapping. By default the SEH register number is just the same
316  /// as the LLVM register number.
317  /// FIXME: TableGen these numbers. Currently this requires target specific
318  /// initialization code.
319  void mapLLVMRegToSEHReg(unsigned LLVMReg, int SEHReg) {
320  L2SEHRegs[LLVMReg] = SEHReg;
321  }
322 
323  void mapLLVMRegToCVReg(unsigned LLVMReg, int CVReg) {
324  L2CVRegs[LLVMReg] = CVReg;
325  }
326 
327  /// \brief This method should return the register where the return
328  /// address can be found.
329  unsigned getRARegister() const {
330  return RAReg;
331  }
332 
333  /// Return the register which is the program counter.
334  unsigned getProgramCounter() const {
335  return PCReg;
336  }
337 
338  const MCRegisterDesc &operator[](unsigned RegNo) const {
339  assert(RegNo < NumRegs &&
340  "Attempting to access record for invalid register number!");
341  return Desc[RegNo];
342  }
343 
344  /// \brief Provide a get method, equivalent to [], but more useful with a
345  /// pointer to this object.
346  const MCRegisterDesc &get(unsigned RegNo) const {
347  return operator[](RegNo);
348  }
349 
350  /// \brief Returns the physical register number of sub-register "Index"
351  /// for physical register RegNo. Return zero if the sub-register does not
352  /// exist.
353  unsigned getSubReg(unsigned Reg, unsigned Idx) const;
354 
355  /// \brief Return a super-register of the specified register
356  /// Reg so its sub-register of index SubIdx is Reg.
357  unsigned getMatchingSuperReg(unsigned Reg, unsigned SubIdx,
358  const MCRegisterClass *RC) const;
359 
360  /// \brief For a given register pair, return the sub-register index
361  /// if the second register is a sub-register of the first. Return zero
362  /// otherwise.
363  unsigned getSubRegIndex(unsigned RegNo, unsigned SubRegNo) const;
364 
365  /// \brief Get the size of the bit range covered by a sub-register index.
366  /// If the index isn't continuous, return the sum of the sizes of its parts.
367  /// If the index is used to access subregisters of different sizes, return -1.
368  unsigned getSubRegIdxSize(unsigned Idx) const;
369 
370  /// \brief Get the offset of the bit range covered by a sub-register index.
371  /// If an Offset doesn't make sense (the index isn't continuous, or is used to
372  /// access sub-registers at different offsets), return -1.
373  unsigned getSubRegIdxOffset(unsigned Idx) const;
374 
375  /// \brief Return the human-readable symbolic target-specific name for the
376  /// specified physical register.
377  const char *getName(unsigned RegNo) const {
378  return RegStrings + get(RegNo).Name;
379  }
380 
381  /// \brief Return the number of registers this target has (useful for
382  /// sizing arrays holding per register information)
383  unsigned getNumRegs() const {
384  return NumRegs;
385  }
386 
387  /// \brief Return the number of sub-register indices
388  /// understood by the target. Index 0 is reserved for the no-op sub-register,
389  /// while 1 to getNumSubRegIndices() - 1 represent real sub-registers.
390  unsigned getNumSubRegIndices() const {
391  return NumSubRegIndices;
392  }
393 
394  /// \brief Return the number of (native) register units in the
395  /// target. Register units are numbered from 0 to getNumRegUnits() - 1. They
396  /// can be accessed through MCRegUnitIterator defined below.
397  unsigned getNumRegUnits() const {
398  return NumRegUnits;
399  }
400 
401  /// \brief Map a target register to an equivalent dwarf register
402  /// number. Returns -1 if there is no equivalent value. The second
403  /// parameter allows targets to use different numberings for EH info and
404  /// debugging info.
405  int getDwarfRegNum(unsigned RegNum, bool isEH) const;
406 
407  /// \brief Map a dwarf register back to a target register.
408  int getLLVMRegNum(unsigned RegNum, bool isEH) const;
409 
410  /// \brief Map a target register to an equivalent SEH register
411  /// number. Returns LLVM register number if there is no equivalent value.
412  int getSEHRegNum(unsigned RegNum) const;
413 
414  /// \brief Map a target register to an equivalent CodeView register
415  /// number.
416  int getCodeViewRegNum(unsigned RegNum) const;
417 
418  regclass_iterator regclass_begin() const { return Classes; }
419  regclass_iterator regclass_end() const { return Classes+NumClasses; }
421  return make_range(regclass_begin(), regclass_end());
422  }
423 
424  unsigned getNumRegClasses() const {
425  return (unsigned)(regclass_end()-regclass_begin());
426  }
427 
428  /// \brief Returns the register class associated with the enumeration
429  /// value. See class MCOperandInfo.
430  const MCRegisterClass& getRegClass(unsigned i) const {
431  assert(i < getNumRegClasses() && "Register Class ID out of range");
432  return Classes[i];
433  }
434 
435  const char *getRegClassName(const MCRegisterClass *Class) const {
436  return RegClassStrings + Class->NameIdx;
437  }
438 
439  /// \brief Returns the encoding for RegNo
440  uint16_t getEncodingValue(unsigned RegNo) const {
441  assert(RegNo < NumRegs &&
442  "Attempting to get encoding for invalid register number!");
443  return RegEncodingTable[RegNo];
444  }
445 
446  /// \brief Returns true if RegB is a sub-register of RegA.
447  bool isSubRegister(unsigned RegA, unsigned RegB) const {
448  return isSuperRegister(RegB, RegA);
449  }
450 
451  /// \brief Returns true if RegB is a super-register of RegA.
452  bool isSuperRegister(unsigned RegA, unsigned RegB) const;
453 
454  /// \brief Returns true if RegB is a sub-register of RegA or if RegB == RegA.
455  bool isSubRegisterEq(unsigned RegA, unsigned RegB) const {
456  return isSuperRegisterEq(RegB, RegA);
457  }
458 
459  /// \brief Returns true if RegB is a super-register of RegA or if
460  /// RegB == RegA.
461  bool isSuperRegisterEq(unsigned RegA, unsigned RegB) const {
462  return RegA == RegB || isSuperRegister(RegA, RegB);
463  }
464 
465  /// \brief Returns true if RegB is a super-register or sub-register of RegA
466  /// or if RegB == RegA.
467  bool isSuperOrSubRegisterEq(unsigned RegA, unsigned RegB) const {
468  return isSubRegisterEq(RegA, RegB) || isSuperRegister(RegA, RegB);
469  }
470 };
471 
472 //===----------------------------------------------------------------------===//
473 // Register List Iterators
474 //===----------------------------------------------------------------------===//
475 
476 // MCRegisterInfo provides lists of super-registers, sub-registers, and
477 // aliasing registers. Use these iterator classes to traverse the lists.
478 
479 /// MCSubRegIterator enumerates all sub-registers of Reg.
480 /// If IncludeSelf is set, Reg itself is included in the list.
482 public:
483  MCSubRegIterator(unsigned Reg, const MCRegisterInfo *MCRI,
484  bool IncludeSelf = false) {
485  init(Reg, MCRI->DiffLists + MCRI->get(Reg).SubRegs);
486  // Initially, the iterator points to Reg itself.
487  if (!IncludeSelf)
488  ++*this;
489  }
490 };
491 
492 /// Iterator that enumerates the sub-registers of a Reg and the associated
493 /// sub-register indices.
495  MCSubRegIterator SRIter;
496  const uint16_t *SRIndex;
497 
498 public:
499  /// Constructs an iterator that traverses subregisters and their
500  /// associated subregister indices.
501  MCSubRegIndexIterator(unsigned Reg, const MCRegisterInfo *MCRI)
502  : SRIter(Reg, MCRI) {
503  SRIndex = MCRI->SubRegIndices + MCRI->get(Reg).SubRegIndices;
504  }
505 
506  /// Returns current sub-register.
507  unsigned getSubReg() const {
508  return *SRIter;
509  }
510 
511  /// Returns sub-register index of the current sub-register.
512  unsigned getSubRegIndex() const {
513  return *SRIndex;
514  }
515 
516  /// Returns true if this iterator is not yet at the end.
517  bool isValid() const { return SRIter.isValid(); }
518 
519  /// Moves to the next position.
520  void operator++() {
521  ++SRIter;
522  ++SRIndex;
523  }
524 };
525 
526 /// MCSuperRegIterator enumerates all super-registers of Reg.
527 /// If IncludeSelf is set, Reg itself is included in the list.
529 public:
530  MCSuperRegIterator() = default;
531 
532  MCSuperRegIterator(unsigned Reg, const MCRegisterInfo *MCRI,
533  bool IncludeSelf = false) {
534  init(Reg, MCRI->DiffLists + MCRI->get(Reg).SuperRegs);
535  // Initially, the iterator points to Reg itself.
536  if (!IncludeSelf)
537  ++*this;
538  }
539 };
540 
541 // Definition for isSuperRegister. Put it down here since it needs the
542 // iterator defined above in addition to the MCRegisterInfo class itself.
543 inline bool MCRegisterInfo::isSuperRegister(unsigned RegA, unsigned RegB) const{
544  for (MCSuperRegIterator I(RegA, this); I.isValid(); ++I)
545  if (*I == RegB)
546  return true;
547  return false;
548 }
549 
550 //===----------------------------------------------------------------------===//
551 // Register Units
552 //===----------------------------------------------------------------------===//
553 
554 // Register units are used to compute register aliasing. Every register has at
555 // least one register unit, but it can have more. Two registers overlap if and
556 // only if they have a common register unit.
557 //
558 // A target with a complicated sub-register structure will typically have many
559 // fewer register units than actual registers. MCRI::getNumRegUnits() returns
560 // the number of register units in the target.
561 
562 // MCRegUnitIterator enumerates a list of register units for Reg. The list is
563 // in ascending numerical order.
565 public:
566  /// MCRegUnitIterator - Create an iterator that traverses the register units
567  /// in Reg.
568  MCRegUnitIterator() = default;
569 
570  MCRegUnitIterator(unsigned Reg, const MCRegisterInfo *MCRI) {
571  assert(Reg && "Null register has no regunits");
572  // Decode the RegUnits MCRegisterDesc field.
573  unsigned RU = MCRI->get(Reg).RegUnits;
574  unsigned Scale = RU & 15;
575  unsigned Offset = RU >> 4;
576 
577  // Initialize the iterator to Reg * Scale, and the List pointer to
578  // DiffLists + Offset.
579  init(Reg * Scale, MCRI->DiffLists + Offset);
580 
581  // That may not be a valid unit, we need to advance by one to get the real
582  // unit number. The first differential can be 0 which would normally
583  // terminate the list, but since we know every register has at least one
584  // unit, we can allow a 0 differential here.
585  advance();
586  }
587 };
588 
589 /// MCRegUnitMaskIterator enumerates a list of register units and their
590 /// associated lane masks for Reg. The register units are in ascending
591 /// numerical order.
593  MCRegUnitIterator RUIter;
594  const LaneBitmask *MaskListIter;
595 
596 public:
597  MCRegUnitMaskIterator() = default;
598 
599  /// Constructs an iterator that traverses the register units and their
600  /// associated LaneMasks in Reg.
601  MCRegUnitMaskIterator(unsigned Reg, const MCRegisterInfo *MCRI)
602  : RUIter(Reg, MCRI) {
603  uint16_t Idx = MCRI->get(Reg).RegUnitLaneMasks;
604  MaskListIter = &MCRI->RegUnitMaskSequences[Idx];
605  }
606 
607  /// Returns a (RegUnit, LaneMask) pair.
608  std::pair<unsigned,LaneBitmask> operator*() const {
609  return std::make_pair(*RUIter, *MaskListIter);
610  }
611 
612  /// Returns true if this iterator is not yet at the end.
613  bool isValid() const { return RUIter.isValid(); }
614 
615  /// Moves to the next position.
616  void operator++() {
617  ++MaskListIter;
618  ++RUIter;
619  }
620 };
621 
622 // Each register unit has one or two root registers. The complete set of
623 // registers containing a register unit is the union of the roots and their
624 // super-registers. All registers aliasing Unit can be visited like this:
625 //
626 // for (MCRegUnitRootIterator RI(Unit, MCRI); RI.isValid(); ++RI) {
627 // for (MCSuperRegIterator SI(*RI, MCRI, true); SI.isValid(); ++SI)
628 // visit(*SI);
629 // }
630 
631 /// MCRegUnitRootIterator enumerates the root registers of a register unit.
633  uint16_t Reg0 = 0;
634  uint16_t Reg1 = 0;
635 
636 public:
637  MCRegUnitRootIterator() = default;
638 
639  MCRegUnitRootIterator(unsigned RegUnit, const MCRegisterInfo *MCRI) {
640  assert(RegUnit < MCRI->getNumRegUnits() && "Invalid register unit");
641  Reg0 = MCRI->RegUnitRoots[RegUnit][0];
642  Reg1 = MCRI->RegUnitRoots[RegUnit][1];
643  }
644 
645  /// \brief Dereference to get the current root register.
646  unsigned operator*() const {
647  return Reg0;
648  }
649 
650  /// \brief Check if the iterator is at the end of the list.
651  bool isValid() const {
652  return Reg0;
653  }
654 
655  /// \brief Preincrement to move to the next root register.
656  void operator++() {
657  assert(isValid() && "Cannot move off the end of the list.");
658  Reg0 = Reg1;
659  Reg1 = 0;
660  }
661 };
662 
663 /// MCRegAliasIterator enumerates all registers aliasing Reg. If IncludeSelf is
664 /// set, Reg itself is included in the list. This iterator does not guarantee
665 /// any ordering or that entries are unique.
667 private:
668  unsigned Reg;
669  const MCRegisterInfo *MCRI;
670  bool IncludeSelf;
671 
675 
676 public:
677  MCRegAliasIterator(unsigned Reg, const MCRegisterInfo *MCRI,
678  bool IncludeSelf)
679  : Reg(Reg), MCRI(MCRI), IncludeSelf(IncludeSelf) {
680  // Initialize the iterators.
681  for (RI = MCRegUnitIterator(Reg, MCRI); RI.isValid(); ++RI) {
682  for (RRI = MCRegUnitRootIterator(*RI, MCRI); RRI.isValid(); ++RRI) {
683  for (SI = MCSuperRegIterator(*RRI, MCRI, true); SI.isValid(); ++SI) {
684  if (!(!IncludeSelf && Reg == *SI))
685  return;
686  }
687  }
688  }
689  }
690 
691  bool isValid() const { return RI.isValid(); }
692 
693  unsigned operator*() const {
694  assert(SI.isValid() && "Cannot dereference an invalid iterator.");
695  return *SI;
696  }
697 
698  void advance() {
699  // Assuming SI is valid.
700  ++SI;
701  if (SI.isValid()) return;
702 
703  ++RRI;
704  if (RRI.isValid()) {
705  SI = MCSuperRegIterator(*RRI, MCRI, true);
706  return;
707  }
708 
709  ++RI;
710  if (RI.isValid()) {
711  RRI = MCRegUnitRootIterator(*RI, MCRI);
712  SI = MCSuperRegIterator(*RRI, MCRI, true);
713  }
714  }
715 
716  void operator++() {
717  assert(isValid() && "Cannot move off the end of the list.");
718  do advance();
719  while (!IncludeSelf && isValid() && *SI == Reg);
720  }
721 };
722 
723 } // end namespace llvm
724 
725 #endif // LLVM_MC_MCREGISTERINFO_H
bool isSuperRegisterEq(unsigned RegA, unsigned RegB) const
Returns true if RegB is a super-register of RegA or if RegB == RegA.
uint64_t CallInst * C
A common definition of LaneBitmask for use in TableGen and CodeGen.
const uint8_t *const RegSet
void operator++()
Pre-increment to move to the next position.
iterator begin() const
begin/end - Return all of the registers in this class.
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
const uint32_t NameIdx
This provides a very simple, boring adaptor for a begin and end iterator into a range type...
bool contains(unsigned Reg1, unsigned Reg2) const
contains - Return true if both registers are in this class.
const MCRegisterDesc & operator[](unsigned RegNo) const
unsigned getNumRegUnits() const
Return the number of (native) register units in the target.
unsigned getID() const
getID() - Return the register class ID number.
SI optimize exec mask operations pre RA
MCSubRegIterator(unsigned Reg, const MCRegisterInfo *MCRI, bool IncludeSelf=false)
bool isValid() const
Returns true if this iterator is not yet at the end.
MCRegUnitMaskIterator enumerates a list of register units and their associated lane masks for Reg...
MCSuperRegIterator enumerates all super-registers of Reg.
bool contains(unsigned Reg) const
contains - Return true if the specified register is included in this register class.
regclass_iterator regclass_begin() const
const iterator RegsBegin
bool isSubRegister(unsigned RegA, unsigned RegB) const
Returns true if RegB is a sub-register of RegA.
MCRegUnitIterator(unsigned Reg, const MCRegisterInfo *MCRI)
Reg
All possible values of the reg field in the ModR/M byte.
void InitMCRegisterInfo(const MCRegisterDesc *D, unsigned NR, unsigned RA, unsigned PC, const MCRegisterClass *C, unsigned NC, const MCPhysReg(*RURoots)[2], unsigned NRU, const MCPhysReg *DL, const LaneBitmask *RUMS, const char *Strings, const char *ClassStrings, const uint16_t *SubIndices, unsigned NumIndices, const SubRegCoveredBits *SubIdxRanges, const uint16_t *RET)
Initialize MCRegisterInfo, called by TableGen auto-generated routines.
unsigned getSize() const
Temporary function to allow out-of-tree targets to switch.
MCRegUnitRootIterator enumerates the root registers of a register unit.
unsigned getSubRegIndex() const
Returns sub-register index of the current sub-register.
unsigned getRegister(unsigned i) const
getRegister - Return the specified register in the class.
DiffListIterator - Base iterator class that can traverse the differentially encoded register and regu...
MCRegUnitMaskIterator(unsigned Reg, const MCRegisterInfo *MCRI)
Constructs an iterator that traverses the register units and their associated LaneMasks in Reg...
MCRegisterClass - Base class of TargetRegisterClass.
unsigned getNumRegs() const
getNumRegs - Return the number of registers in this class.
uint16_t MCPhysReg
An unsigned integer type large enough to represent all physical registers, but not necessarily virtua...
const char * getName(unsigned RegNo) const
Return the human-readable symbolic target-specific name for the specified physical register...
MCRegisterInfo base class - We assume that the target defines a static array of MCRegisterDesc object...
bool isSuperRegister(unsigned RegA, unsigned RegB) const
Returns true if RegB is a super-register of RegA.
const uint16_t PhysRegSize
unsigned getNumRegs() const
Return the number of registers this target has (useful for sizing arrays holding per register informa...
void operator++()
Moves to the next position.
initializer< Ty > init(const Ty &Val)
Definition: CommandLine.h:406
unsigned operator*() const
Dereference to get the current root register.
SubRegCoveredBits - Emitted by tablegen: bit range covered by a subreg index, -1 in any being invalid...
unsigned getSubReg() const
Returns current sub-register.
Iterator that enumerates the sub-registers of a Reg and the associated sub-register indices...
void mapLLVMRegsToDwarfRegs(const DwarfLLVMRegPair *Map, unsigned Size, bool isEH)
Used to initialize LLVM register to Dwarf register number mapping.
unsigned getPhysRegSize() const
Return the size of the physical register in bytes.
void mapDwarfRegsToLLVMRegs(const DwarfLLVMRegPair *Map, unsigned Size, bool isEH)
Used to initialize Dwarf register to LLVM register number mapping.
const MCPhysReg * const_iterator
MCRegAliasIterator enumerates all registers aliasing Reg.
int getCopyCost() const
getCopyCost - Return the cost of copying a value between two registers in this class.
MCRegAliasIterator(unsigned Reg, const MCRegisterInfo *MCRI, bool IncludeSelf)
iterator end() const
iterator_range< regclass_iterator > regclasses() const
std::pair< unsigned, LaneBitmask > operator*() const
Returns a (RegUnit, LaneMask) pair.
MCSubRegIterator enumerates all sub-registers of Reg.
unsigned getNumRegClasses() const
iterator_range< T > make_range(T x, T y)
Convenience function for iterating over sub-ranges.
MCRegisterDesc - This record contains information about a particular register.
DwarfLLVMRegPair - Emitted by tablegen so Dwarf<->LLVM reg mappings can be performed with a binary se...
const char * getRegClassName(const MCRegisterClass *Class) const
MCSubRegIndexIterator(unsigned Reg, const MCRegisterInfo *MCRI)
Constructs an iterator that traverses subregisters and their associated subregister indices...
bool isSubRegisterEq(unsigned RegA, unsigned RegB) const
Returns true if RegB is a sub-register of RegA or if RegB == RegA.
const MCRegisterDesc & get(unsigned RegNo) const
Provide a get method, equivalent to [], but more useful with a pointer to this object.
bool isValid() const
Returns true if this iterator is not yet at the end.
MCSuperRegIterator(unsigned Reg, const MCRegisterInfo *MCRI, bool IncludeSelf=false)
bool isSuperOrSubRegisterEq(unsigned RegA, unsigned RegB) const
Returns true if RegB is a super-register or sub-register of RegA or if RegB == RegA.
static GCRegistry::Add< StatepointGC > D("statepoint-example", "an example strategy for statepoint")
#define NC
Definition: regutils.h:42
unsigned operator*() const
MCRegUnitRootIterator(unsigned RegUnit, const MCRegisterInfo *MCRI)
A range adaptor for a pair of iterators.
bool isValid() const
isValid - returns true if this iterator is not yet at the end.
bool operator<(DwarfLLVMRegPair RHS) const
uint16_t RegUnitLaneMasks
Index into list with lane mask sequences.
regclass_iterator regclass_end() const
uint16_t getEncodingValue(unsigned RegNo) const
Returns the encoding for RegNo.
void mapLLVMRegToCVReg(unsigned LLVMReg, int CVReg)
const uint16_t RegSetSize
const NodeList & List
Definition: RDFGraph.cpp:210
#define I(x, y, z)
Definition: MD5.cpp:58
unsigned getNumSubRegIndices() const
Return the number of sub-register indices understood by the target.
unsigned advance()
advance - Move to the next list position, return the applied differential.
void operator++()
Moves to the next position.
unsigned getRARegister() const
This method should return the register where the return address can be found.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
constexpr char Size[]
Key for Kernel::Arg::Metadata::mSize.
unsigned getProgramCounter() const
Return the register which is the program counter.
void operator++()
Preincrement to move to the next root register.
static unsigned getDwarfRegNum(unsigned Reg, const TargetRegisterInfo *TRI)
Go up the super-register chain until we hit a valid dwarf register number.
Definition: StackMaps.cpp:93
unsigned operator*() const
Dereference the iterator to get the value at the current position.
bool isValid() const
Check if the iterator is at the end of the list.
const MCPhysReg * iterator
const uint16_t RegsSize
void mapLLVMRegToSEHReg(unsigned LLVMReg, int SEHReg)
mapLLVMRegToSEHReg - Used to initialize LLVM register to SEH register number mapping.
bool isAllocatable() const
isAllocatable - Return true if this register class may be used to create virtual registers.
void init(MCPhysReg InitVal, const MCPhysReg *DiffList)
init - Point the iterator to InitVal, decoding subsequent values from DiffList.
const MCRegisterClass & getRegClass(unsigned i) const
Returns the register class associated with the enumeration value.