uint32_t Overlaps; // Overlapping registers, described above
uint32_t SubRegs; // Sub-register set, described above
uint32_t SuperRegs; // Super-register set, described above
+
+ // RegUnits - Points to the list of register units. The low 4 bits holds the
+ // Scale, the high bits hold an offset into DiffLists. See MCRegUnitIterator.
+ uint32_t RegUnits;
};
/// MCRegisterInfo base class - We assume that the target defines a static
unsigned RAReg; // Return address register
const MCRegisterClass *Classes; // Pointer to the regclass array
unsigned NumClasses; // Number of entries in the array
+ unsigned NumRegUnits; // Number of regunits.
+ const uint16_t (*RegUnitRoots)[2]; // Pointer to regunit root table.
const uint16_t *RegLists; // Pointer to the reglists array
+ const uint16_t *DiffLists; // Pointer to the difflists array
const char *RegStrings; // Pointer to the string table.
const uint16_t *SubRegIndices; // Pointer to the subreg lookup
// array.
DenseMap<unsigned, int> L2SEHRegs; // LLVM to SEH regs mapping
public:
+ /// RegListIterator. This iterator class is used to traverse lists of
+ /// super-registers, sub-registers, and overlapping registers. Don't use it
+ /// directly, use one of the sub-classes defined below.
+ class RegListIterator {
+ const uint16_t *Pos;
+ public:
+ explicit RegListIterator(const uint16_t *Table)
+ : Pos(Table) {}
+
+ /// isValid - Return false when the end of the list is reached.
+ bool isValid() const { return *Pos; }
+
+ /// Dereference the iterator to get the current register.
+ unsigned operator*() const { return *Pos; }
+
+ /// Pre-increment. Move to the next register.
+ void operator++() { ++Pos; }
+ };
+
+ /// DiffListIterator - Base iterator class that can traverse the
+ /// differentially encoded register and regunit lists in DiffLists.
+ /// Don't use this class directly, use one of the specialized sub-classes
+ /// defined below.
+ class DiffListIterator {
+ uint16_t Val;
+ const uint16_t *List;
+
+ protected:
+ /// Create an invalid iterator. Call init() to point to something useful.
+ DiffListIterator() : Val(0), List(0) {}
+
+ /// init - Point the iterator to InitVal, decoding subsequent values from
+ /// DiffList. The iterator will initially point to InitVal, sub-classes are
+ /// responsible for skipping the seed value if it is not part of the list.
+ void init(uint16_t InitVal, const uint16_t *DiffList) {
+ Val = InitVal;
+ List = DiffList;
+ }
+
+ /// advance - Move to the next list position, return the applied
+ /// differential. This function does not detect the end of the list, that
+ /// is the caller's responsibility (by checking for a 0 return value).
+ unsigned advance() {
+ assert(isValid() && "Cannot move off the end of the list.");
+ uint16_t D = *List++;
+ Val += D;
+ return D;
+ }
+
+ public:
+
+ /// isValid - returns true if this iterator is not yet at the end.
+ bool isValid() const { return List; }
+
+ /// Dereference the iterator to get the value at the current position.
+ unsigned operator*() const { return Val; }
+
+ /// Pre-increment to move to the next position.
+ void operator++() {
+ // The end of the list is encoded as a 0 differential.
+ if (!advance())
+ List = 0;
+ }
+ };
+
+ // These iterators are allowed to sub-class RegListIterator and
+ // DiffListIterator and access internal list pointers.
+ friend class MCSubRegIterator;
+ friend class MCSuperRegIterator;
+ friend class MCRegAliasIterator;
+ friend class MCRegUnitIterator;
+ friend class MCRegUnitRootIterator;
+
/// InitMCRegisterInfo - Initialize MCRegisterInfo, called by TableGen
/// auto-generated routines. *DO NOT USE*.
void InitMCRegisterInfo(const MCRegisterDesc *D, unsigned NR, unsigned RA,
const MCRegisterClass *C, unsigned NC,
+ const uint16_t (*RURoots)[2],
+ unsigned NRU,
const uint16_t *RL,
+ const uint16_t *DL,
const char *Strings,
const uint16_t *SubIndices,
unsigned NumIndices,
RAReg = RA;
Classes = C;
RegLists = RL;
+ DiffLists = DL;
RegStrings = Strings;
NumClasses = NC;
+ RegUnitRoots = RURoots;
+ NumRegUnits = NRU;
SubRegIndices = SubIndices;
NumSubRegIndices = NumIndices;
RegEncodingTable = RET;
return operator[](RegNo);
}
- /// getAliasSet - Return the set of registers aliased by the specified
- /// register, or a null list of there are none. The list returned is zero
- /// terminated.
- ///
- const uint16_t *getAliasSet(unsigned RegNo) const {
- // The Overlaps set always begins with Reg itself.
- return RegLists + get(RegNo).Overlaps + 1;
- }
-
- /// getOverlaps - Return a list of registers that overlap Reg, including
- /// itself. This is the same as the alias set except Reg is included in the
- /// list.
- /// These are exactly the registers in { x | regsOverlap(x, Reg) }.
- ///
- const uint16_t *getOverlaps(unsigned RegNo) const {
- return RegLists + get(RegNo).Overlaps;
- }
-
- /// getSubRegisters - Return the list of registers that are sub-registers of
- /// the specified register, or a null list of there are none. The list
- /// returned is zero terminated and sorted according to super-sub register
- /// relations. e.g. X86::RAX's sub-register list is EAX, AX, AL, AH.
- ///
- const uint16_t *getSubRegisters(unsigned RegNo) const {
- return RegLists + get(RegNo).SubRegs;
- }
-
/// getSubReg - Returns the physical register number of sub-register "Index"
/// for physical register RegNo. Return zero if the sub-register does not
/// exist.
/// getMatchingSuperReg - Return a super-register of the specified register
/// Reg so its sub-register of index SubIdx is Reg.
unsigned getMatchingSuperReg(unsigned Reg, unsigned SubIdx,
- const MCRegisterClass *RC) const {
- for (const uint16_t *SRs = getSuperRegisters(Reg); unsigned SR = *SRs;++SRs)
- if (Reg == getSubReg(SR, SubIdx) && RC->contains(SR))
- return SR;
- return 0;
- }
+ const MCRegisterClass *RC) const;
/// getSubRegIndex - For a given register pair, return the sub-register index
/// if the second register is a sub-register of the first. Return zero
return 0;
}
- /// getSuperRegisters - Return the list of registers that are super-registers
- /// of the specified register, or a null list of there are none. The list
- /// returned is zero terminated and sorted according to super-sub register
- /// relations. e.g. X86::AL's super-register list is AX, EAX, RAX.
- ///
- const uint16_t *getSuperRegisters(unsigned RegNo) const {
- return RegLists + get(RegNo).SuperRegs;
- }
-
/// getName - Return the human-readable symbolic target-specific name for the
/// specified physical register.
const char *getName(unsigned RegNo) const {
return NumRegs;
}
+ /// getNumRegUnits - Return the number of (native) register units in the
+ /// target. Register units are numbered from 0 to getNumRegUnits() - 1. They
+ /// can be accessed through MCRegUnitIterator defined below.
+ unsigned getNumRegUnits() const {
+ return NumRegUnits;
+ }
+
/// getDwarfRegNum - Map a target register to an equivalent dwarf register
/// number. Returns -1 if there is no equivalent value. The second
/// parameter allows targets to use different numberings for EH info and
};
+//===----------------------------------------------------------------------===//
+// Register List Iterators
+//===----------------------------------------------------------------------===//
+
+// MCRegisterInfo provides lists of super-registers, sub-registers, and
+// aliasing registers. Use these iterator classes to traverse the lists.
+
+/// MCSubRegIterator enumerates all sub-registers of Reg.
+class MCSubRegIterator : public MCRegisterInfo::RegListIterator {
+public:
+ MCSubRegIterator(unsigned Reg, const MCRegisterInfo *MCRI)
+ : RegListIterator(MCRI->RegLists + MCRI->get(Reg).SubRegs) {}
+};
+
+/// MCSuperRegIterator enumerates all super-registers of Reg.
+class MCSuperRegIterator : public MCRegisterInfo::RegListIterator {
+public:
+ MCSuperRegIterator(unsigned Reg, const MCRegisterInfo *MCRI)
+ : RegListIterator(MCRI->RegLists + MCRI->get(Reg).SuperRegs) {}
+};
+
+/// MCRegAliasIterator enumerates all registers aliasing Reg.
+/// If IncludeSelf is set, Reg itself is included in the list.
+class MCRegAliasIterator : public MCRegisterInfo::RegListIterator {
+public:
+ MCRegAliasIterator(unsigned Reg, const MCRegisterInfo *MCRI, bool IncludeSelf)
+ : RegListIterator(MCRI->RegLists + MCRI->get(Reg).Overlaps + !IncludeSelf)
+ {}
+};
+
+inline
+unsigned MCRegisterInfo::getMatchingSuperReg(unsigned Reg, unsigned SubIdx,
+ const MCRegisterClass *RC) const {
+ for (MCSuperRegIterator Supers(Reg, this); Supers.isValid(); ++Supers)
+ if (Reg == getSubReg(*Supers, SubIdx) && RC->contains(*Supers))
+ return *Supers;
+ return 0;
+}
+
+//===----------------------------------------------------------------------===//
+// Register Units
+//===----------------------------------------------------------------------===//
+
+// Register units are used to compute register aliasing. Every register has at
+// least one register unit, but it can have more. Two registers overlap if and
+// only if they have a common register unit.
+//
+// A target with a complicated sub-register structure will typically have many
+// fewer register units than actual registers. MCRI::getNumRegUnits() returns
+// the number of register units in the target.
+
+// MCRegUnitIterator enumerates a list of register units for Reg. The list is
+// in ascending numerical order.
+class MCRegUnitIterator : public MCRegisterInfo::DiffListIterator {
+public:
+ /// MCRegUnitIterator - Create an iterator that traverses the register units
+ /// in Reg.
+ MCRegUnitIterator(unsigned Reg, const MCRegisterInfo *MCRI) {
+ // Decode the RegUnits MCRegisterDesc field.
+ unsigned RU = MCRI->get(Reg).RegUnits;
+ unsigned Scale = RU & 15;
+ unsigned Offset = RU >> 4;
+
+ // Initialize the iterator to Reg * Scale, and the List pointer to
+ // DiffLists + Offset.
+ init(Reg * Scale, MCRI->DiffLists + Offset);
+
+ // That may not be a valid unit, we need to advance by one to get the real
+ // unit number. The first differential can be 0 which would normally
+ // terminate the list, but since we know every register has at least one
+ // unit, we can allow a 0 differential here.
+ advance();
+ }
+};
+
+// Each register unit has one or two root registers. The complete set of
+// registers containing a register unit is the union of the roots and their
+// super-registers. All registers aliasing Unit can be visited like this:
+//
+// for (MCRegUnitRootIterator RI(Unit, MCRI); RI.isValid(); ++RI) {
+// unsigned Root = *RI;
+// visit(Root);
+// for (MCSuperRegIterator SI(Root, MCRI); SI.isValid(); ++SI)
+// visit(*SI);
+// }
+
+/// MCRegUnitRootIterator enumerates the root registers of a register unit.
+class MCRegUnitRootIterator {
+ uint16_t Reg0;
+ uint16_t Reg1;
+public:
+ MCRegUnitRootIterator(unsigned RegUnit, const MCRegisterInfo *MCRI) {
+ assert(RegUnit < MCRI->getNumRegUnits() && "Invalid register unit");
+ Reg0 = MCRI->RegUnitRoots[RegUnit][0];
+ Reg1 = MCRI->RegUnitRoots[RegUnit][1];
+ }
+
+ /// Dereference to get the current root register.
+ unsigned operator*() const {
+ return Reg0;
+ }
+
+ /// isValid - Check if the iterator is at the end of the list.
+ bool isValid() const {
+ return Reg0;
+ }
+
+ /// Preincrement to move to the next root register.
+ void operator++() {
+ assert(isValid() && "Cannot move off the end of the list.");
+ Reg0 = Reg1;
+ Reg1 = 0;
+ }
+};
+
} // End llvm namespace
#endif
projects / oota-llvm.git / blobdiff