#ifndef LLVM_MC_MCREGISTERINFO_H
#define LLVM_MC_MCREGISTERINFO_H
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/Support/ErrorHandling.h"
#include <cassert>
namespace llvm {
-/// TargetRegisterDesc - This record contains all of the information known about
+/// An unsigned integer type large enough to represent all physical registers,
+/// but not necessarily virtual registers.
+typedef uint16_t MCPhysReg;
+
+/// MCRegisterClass - Base class of TargetRegisterClass.
+class MCRegisterClass {
+public:
+ typedef const MCPhysReg* iterator;
+ typedef const MCPhysReg* const_iterator;
+
+ const char *Name;
+ const iterator RegsBegin;
+ const uint8_t *const RegSet;
+ const uint16_t RegsSize;
+ const uint16_t RegSetSize;
+ const uint16_t ID;
+ const uint16_t RegSize, Alignment; // Size & Alignment of register in bytes
+ const int8_t CopyCost;
+ const bool Allocatable;
+
+ /// getID() - Return the register class ID number.
+ ///
+ unsigned getID() const { return ID; }
+
+ /// getName() - Return the register class name for debugging.
+ ///
+ const char *getName() const { return Name; }
+
+ /// begin/end - Return all of the registers in this class.
+ ///
+ iterator begin() const { return RegsBegin; }
+ iterator end() const { return RegsBegin + RegsSize; }
+
+ /// getNumRegs - Return the number of registers in this class.
+ ///
+ unsigned getNumRegs() const { return RegsSize; }
+
+ /// getRegister - Return the specified register in the class.
+ ///
+ unsigned getRegister(unsigned i) const {
+ assert(i < getNumRegs() && "Register number out of range!");
+ return RegsBegin[i];
+ }
+
+ /// contains - Return true if the specified register is included in this
+ /// register class. This does not include virtual registers.
+ bool contains(unsigned Reg) const {
+ unsigned InByte = Reg % 8;
+ unsigned Byte = Reg / 8;
+ if (Byte >= RegSetSize)
+ return false;
+ return (RegSet[Byte] & (1 << InByte)) != 0;
+ }
+
+ /// contains - Return true if both registers are in this class.
+ bool contains(unsigned Reg1, unsigned Reg2) const {
+ return contains(Reg1) && contains(Reg2);
+ }
+
+ /// getSize - Return the size of the register in bytes, which is also the size
+ /// of a stack slot allocated to hold a spilled copy of this register.
+ unsigned getSize() const { return RegSize; }
+
+ /// getAlignment - Return the minimum required alignment for a register of
+ /// this class.
+ unsigned getAlignment() const { return Alignment; }
+
+ /// getCopyCost - Return the cost of copying a value between two registers in
+ /// this class. A negative number means the register class is very expensive
+ /// to copy e.g. status flag register classes.
+ int getCopyCost() const { return CopyCost; }
+
+ /// isAllocatable - Return true if this register class may be used to create
+ /// virtual registers.
+ bool isAllocatable() const { return Allocatable; }
+};
+
+/// MCRegisterDesc - This record contains all of the information known about
/// a particular register. The Overlaps field contains a pointer to a zero
/// terminated array of registers that this register aliases, starting with
/// itself. This is needed for architectures like X86 which have AL alias AX
/// super-registers of the specific register, e.g. RAX, EAX, are super-registers
/// of AX.
///
-struct TargetRegisterDesc {
- const char *Name; // Printable name for the reg (for debugging)
- const unsigned *Overlaps; // Overlapping registers, described above
- const unsigned *SubRegs; // Sub-register set, described above
- const unsigned *SuperRegs; // Super-register set, described above
+struct MCRegisterDesc {
+ uint32_t Name; // Printable name for the reg (for debugging)
+ uint32_t Overlaps; // Overlapping registers, described above
+ uint32_t SubRegs; // Sub-register set, described above
+ uint32_t SuperRegs; // Super-register set, described above
+
+ // Offset into MCRI::SubRegIndices of a list of sub-register indices for each
+ // sub-register in SubRegs.
+ uint32_t SubRegIndices;
+
+ // 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
-/// array of TargetRegisterDesc objects that represent all of the machine
+/// array of MCRegisterDesc objects that represent all of the machine
/// registers that the target has. As such, we simply have to track a pointer
/// to this array so that we can turn register number into a register
/// descriptor.
///
+/// Note this class is designed to be a base class of TargetRegisterInfo, which
+/// is the interface used by codegen. However, specific targets *should never*
+/// specialize this class. MCRegisterInfo should only contain getters to access
+/// TableGen generated physical register data. It must not be extended with
+/// virtual methods.
+///
class MCRegisterInfo {
+public:
+ typedef const MCRegisterClass *regclass_iterator;
+
+ /// DwarfLLVMRegPair - Emitted by tablegen so Dwarf<->LLVM reg mappings can be
+ /// performed with a binary search.
+ struct DwarfLLVMRegPair {
+ unsigned FromReg;
+ unsigned ToReg;
+
+ bool operator<(DwarfLLVMRegPair RHS) const { return FromReg < RHS.FromReg; }
+ };
private:
- const TargetRegisterDesc *Desc; // Pointer to the descriptor array
+ const MCRegisterDesc *Desc; // Pointer to the descriptor array
unsigned NumRegs; // Number of entries in the array
+ 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 MCPhysReg *DiffLists; // Pointer to the difflists array
+ const char *RegStrings; // Pointer to the string table.
+ const uint16_t *SubRegIndices; // Pointer to the subreg lookup
+ // array.
+ unsigned NumSubRegIndices; // Number of subreg indices.
+ const uint16_t *RegEncodingTable; // Pointer to array of register
+ // encodings.
+
+ unsigned L2DwarfRegsSize;
+ unsigned EHL2DwarfRegsSize;
+ unsigned Dwarf2LRegsSize;
+ unsigned EHDwarf2LRegsSize;
+ const DwarfLLVMRegPair *L2DwarfRegs; // LLVM to Dwarf regs mapping
+ const DwarfLLVMRegPair *EHL2DwarfRegs; // LLVM to Dwarf regs mapping EH
+ const DwarfLLVMRegPair *Dwarf2LRegs; // Dwarf to LLVM regs mapping
+ const DwarfLLVMRegPair *EHDwarf2LRegs; // Dwarf to LLVM regs mapping EH
+ DenseMap<unsigned, int> L2SEHRegs; // LLVM to SEH regs mapping
public:
+ /// 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 MCPhysReg *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(MCPhysReg InitVal, const MCPhysReg *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.");
+ MCPhysReg 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 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 TargetRegisterDesc *D, unsigned NR) {
+ void InitMCRegisterInfo(const MCRegisterDesc *D, unsigned NR, unsigned RA,
+ const MCRegisterClass *C, unsigned NC,
+ const uint16_t (*RURoots)[2],
+ unsigned NRU,
+ const MCPhysReg *DL,
+ const char *Strings,
+ const uint16_t *SubIndices,
+ unsigned NumIndices,
+ const uint16_t *RET) {
Desc = D;
NumRegs = NR;
+ RAReg = RA;
+ Classes = C;
+ DiffLists = DL;
+ RegStrings = Strings;
+ NumClasses = NC;
+ RegUnitRoots = RURoots;
+ NumRegUnits = NRU;
+ SubRegIndices = SubIndices;
+ NumSubRegIndices = NumIndices;
+ RegEncodingTable = RET;
+ }
+
+ /// mapLLVMRegsToDwarfRegs - Used to initialize LLVM register to Dwarf
+ /// register number mapping. Called by TableGen auto-generated routines.
+ /// *DO NOT USE*.
+ void mapLLVMRegsToDwarfRegs(const DwarfLLVMRegPair *Map, unsigned Size,
+ bool isEH) {
+ if (isEH) {
+ EHL2DwarfRegs = Map;
+ EHL2DwarfRegsSize = Size;
+ } else {
+ L2DwarfRegs = Map;
+ L2DwarfRegsSize = Size;
+ }
+ }
+
+ /// mapDwarfRegsToLLVMRegs - Used to initialize Dwarf register to LLVM
+ /// register number mapping. Called by TableGen auto-generated routines.
+ /// *DO NOT USE*.
+ void mapDwarfRegsToLLVMRegs(const DwarfLLVMRegPair *Map, unsigned Size,
+ bool isEH) {
+ if (isEH) {
+ EHDwarf2LRegs = Map;
+ EHDwarf2LRegsSize = Size;
+ } else {
+ Dwarf2LRegs = Map;
+ Dwarf2LRegsSize = Size;
+ }
}
-
- const TargetRegisterDesc &operator[](unsigned RegNo) const {
+
+ /// mapLLVMRegToSEHReg - Used to initialize LLVM register to SEH register
+ /// number mapping. By default the SEH register number is just the same
+ /// as the LLVM register number.
+ /// FIXME: TableGen these numbers. Currently this requires target specific
+ /// initialization code.
+ void mapLLVMRegToSEHReg(unsigned LLVMReg, int SEHReg) {
+ L2SEHRegs[LLVMReg] = SEHReg;
+ }
+
+ /// getRARegister - This method should return the register where the return
+ /// address can be found.
+ unsigned getRARegister() const {
+ return RAReg;
+ }
+
+ const MCRegisterDesc &operator[](unsigned RegNo) const {
assert(RegNo < NumRegs &&
"Attempting to access record for invalid register number!");
return Desc[RegNo];
/// Provide a get method, equivalent to [], but more useful if we have a
/// pointer to this object.
///
- const TargetRegisterDesc &get(unsigned RegNo) const {
+ const MCRegisterDesc &get(unsigned RegNo) const {
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 unsigned *getAliasSet(unsigned RegNo) const {
- // The Overlaps set always begins with Reg itself.
- return 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 unsigned *getOverlaps(unsigned RegNo) const {
- return get(RegNo).Overlaps;
- }
+ /// getSubReg - Returns the physical register number of sub-register "Index"
+ /// for physical register RegNo. Return zero if the sub-register does not
+ /// exist.
+ unsigned getSubReg(unsigned Reg, unsigned Idx) const;
- /// 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 unsigned *getSubRegisters(unsigned RegNo) const {
- return get(RegNo).SubRegs;
- }
+ /// 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;
- /// 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 unsigned *getSuperRegisters(unsigned RegNo) const {
- return get(RegNo).SuperRegs;
- }
+ /// getSubRegIndex - For a given register pair, return the sub-register index
+ /// if the second register is a sub-register of the first. Return zero
+ /// otherwise.
+ unsigned getSubRegIndex(unsigned RegNo, unsigned SubRegNo) const;
/// getName - Return the human-readable symbolic target-specific name for the
/// specified physical register.
const char *getName(unsigned RegNo) const {
- return get(RegNo).Name;
+ return RegStrings + get(RegNo).Name;
}
/// getNumRegs - Return the number of registers this target has (useful for
unsigned getNumRegs() const {
return NumRegs;
}
+
+ /// getNumSubRegIndices - Return the number of sub-register indices
+ /// understood by the target. Index 0 is reserved for the no-op sub-register,
+ /// while 1 to getNumSubRegIndices() - 1 represent real sub-registers.
+ unsigned getNumSubRegIndices() const {
+ return NumSubRegIndices;
+ }
+
+ /// 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
+ /// debugging info.
+ int getDwarfRegNum(unsigned RegNum, bool isEH) const;
+
+ /// getLLVMRegNum - Map a dwarf register back to a target register.
+ ///
+ int getLLVMRegNum(unsigned RegNum, bool isEH) const;
+
+ /// getSEHRegNum - Map a target register to an equivalent SEH register
+ /// number. Returns LLVM register number if there is no equivalent value.
+ int getSEHRegNum(unsigned RegNum) const;
+
+ regclass_iterator regclass_begin() const { return Classes; }
+ regclass_iterator regclass_end() const { return Classes+NumClasses; }
+
+ unsigned getNumRegClasses() const {
+ return (unsigned)(regclass_end()-regclass_begin());
+ }
+
+ /// getRegClass - Returns the register class associated with the enumeration
+ /// value. See class MCOperandInfo.
+ const MCRegisterClass& getRegClass(unsigned i) const {
+ assert(i < getNumRegClasses() && "Register Class ID out of range");
+ return Classes[i];
+ }
+
+ /// getEncodingValue - Returns the encoding for RegNo
+ uint16_t getEncodingValue(unsigned RegNo) const {
+ assert(RegNo < NumRegs &&
+ "Attempting to get encoding for invalid register number!");
+ return RegEncodingTable[RegNo];
+ }
+
+};
+
+//===----------------------------------------------------------------------===//
+// 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::DiffListIterator {
+public:
+ MCSubRegIterator(unsigned Reg, const MCRegisterInfo *MCRI) {
+ init(Reg, MCRI->DiffLists + MCRI->get(Reg).SubRegs);
+ ++*this;
+ }
+};
+
+/// MCSuperRegIterator enumerates all super-registers of Reg.
+class MCSuperRegIterator : public MCRegisterInfo::DiffListIterator {
+public:
+ MCSuperRegIterator(unsigned Reg, const MCRegisterInfo *MCRI) {
+ init(Reg, MCRI->DiffLists + MCRI->get(Reg).SuperRegs);
+ ++*this;
+ }
};
-
+
+/// MCRegAliasIterator enumerates all registers aliasing Reg.
+/// If IncludeSelf is set, Reg itself is included in the list.
+class MCRegAliasIterator : public MCRegisterInfo::DiffListIterator {
+public:
+ MCRegAliasIterator(unsigned Reg, const MCRegisterInfo *MCRI,
+ bool IncludeSelf) {
+ init(Reg, MCRI->DiffLists + MCRI->get(Reg).Overlaps);
+ // Initially, the iterator points to Reg itself.
+ if (!IncludeSelf)
+ ++*this;
+ }
+};
+
+//===----------------------------------------------------------------------===//
+// 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