//===-- llvm/Target/TargetRegInfo.h - Target Register Info -------*- C++ -*-==//
//
// This file is used to describe the register system of a target to the
// register allocator.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_TARGETREGINFO_H
#define LLVM_TARGET_TARGETREGINFO_H
#include "Support/NonCopyable.h"
#include "Support/hash_map"
#include <string>
class TargetMachine;
class IGNode;
class Type;
class Value;
class LiveRangeInfo;
class Function;
class LiveRange;
class AddedInstrns;
class MachineInstr;
class PhyRegAlloc;
class BasicBlock;
///----------------------------------------------------------------------------
/// Interface to description of machine register class (e.g., int reg class
/// float reg class etc)
///
class TargetRegClassInfo {
protected:
const unsigned RegClassID; // integer ID of a reg class
const unsigned NumOfAvailRegs; // # of avail for coloring -without SP etc.
const unsigned NumOfAllRegs; // # of all registers -including SP,g0 etc.
public:
inline unsigned getRegClassID() const { return RegClassID; }
inline unsigned getNumOfAvailRegs() const { return NumOfAvailRegs; }
inline unsigned getNumOfAllRegs() const { return NumOfAllRegs; }
// This method should find a color which is not used by neighbors
// (i.e., a false position in IsColorUsedArr) and
virtual void colorIGNode(IGNode *Node,
std::vector<bool> &IsColorUsedArr) const = 0;
virtual bool isRegVolatile(int Reg) const = 0;
TargetRegClassInfo(unsigned ID, unsigned NVR, unsigned NAR)
: RegClassID(ID), NumOfAvailRegs(NVR), NumOfAllRegs(NAR) {}
};
//---------------------------------------------------------------------------
/// TargetRegInfo - Interface to register info of target machine
///
class TargetRegInfo : public NonCopyableV {
protected:
// A vector of all machine register classes
//
std::vector<const TargetRegClassInfo *> MachineRegClassArr;
public:
const TargetMachine ⌖
TargetRegInfo(const TargetMachine& tgt) : target(tgt) { }
~TargetRegInfo() {
for (unsigned i = 0, e = MachineRegClassArr.size(); i != e; ++i)
delete MachineRegClassArr[i];
}
// According the definition of a MachineOperand class, a Value in a
// machine instruction can go into either a normal register or a
// condition code register. If isCCReg is true below, the ID of the condition
// code register class will be returned. Otherwise, the normal register
// class (eg. int, float) must be returned.
virtual unsigned getRegClassIDOfType (const Type *type,
bool isCCReg = false) const =0;
virtual unsigned getRegClassIDOfValue (const Value *Val,
bool isCCReg = false) const =0;
virtual unsigned getRegClassIDOfReg (int unifiedRegNum) const =0;
virtual unsigned getRegClassIDOfRegType(int regType) const =0;
inline unsigned int getNumOfRegClasses() const {
return MachineRegClassArr.size();
}
const TargetRegClassInfo *getMachineRegClass(unsigned i) const {
return MachineRegClassArr[i];
}
// returns the register that is hardwired to zero if any (-1 if none)
//
virtual int getZeroRegNum() const = 0;
// Number of registers used for passing int args (usually 6: %o0 - %o5)
// and float args (usually 32: %f0 - %f31)
//
virtual unsigned const GetNumOfIntArgRegs() const = 0;
virtual unsigned const GetNumOfFloatArgRegs() const = 0;
// The following methods are used to color special live ranges (e.g.
// method args and return values etc.) with specific hardware registers
// as required. See SparcRegInfo.cpp for the implementation for Sparc.
//
virtual void suggestRegs4MethodArgs(const Function *Func,
LiveRangeInfo &LRI) const = 0;
virtual void suggestRegs4CallArgs(MachineInstr *CallI,
LiveRangeInfo &LRI) const = 0;
virtual void suggestReg4RetValue(MachineInstr *RetI,
LiveRangeInfo &LRI) const = 0;
virtual void colorMethodArgs(const Function *Func, LiveRangeInfo &LRI,
AddedInstrns *FirstAI) const = 0;
virtual void colorCallArgs(MachineInstr *CalI,
LiveRangeInfo& LRI, AddedInstrns *CallAI,
PhyRegAlloc &PRA, const BasicBlock *BB) const = 0;
virtual void colorRetValue(MachineInstr *RetI, LiveRangeInfo &LRI,
AddedInstrns *RetAI) const = 0;
// The following methods are used to generate "copy" machine instructions
// for an architecture. Currently they are used in TargetRegClass
// interface. However, they can be moved to TargetInstrInfo interface if
// necessary.
//
// The function regTypeNeedsScratchReg() can be used to check whether a
// scratch register is needed to copy a register of type `regType' to
// or from memory. If so, such a scratch register can be provided by
// the caller (e.g., if it knows which regsiters are free); otherwise
// an arbitrary one will be chosen and spilled by the copy instructions.
// If a scratch reg is needed, the reg. type that must be used
// for scratch registers is returned in scratchRegType.
//
virtual bool regTypeNeedsScratchReg(int RegType,
int& scratchRegType) const = 0;
virtual void cpReg2RegMI(std::vector<MachineInstr*>& mvec,
unsigned SrcReg, unsigned DestReg,
int RegType) const = 0;
virtual void cpReg2MemMI(std::vector<MachineInstr*>& mvec,
unsigned SrcReg, unsigned DestPtrReg, int Offset,
int RegType, int scratchReg = -1) const=0;
virtual void cpMem2RegMI(std::vector<MachineInstr*>& mvec,
unsigned SrcPtrReg, int Offset, unsigned DestReg,
int RegType, int scratchReg = -1) const=0;
virtual void cpValue2Value(Value *Src, Value *Dest,
std::vector<MachineInstr*>& mvec) const = 0;
virtual bool isRegVolatile(int RegClassID, int Reg) const = 0;
// Returns the reg used for pushing the address when a method is called.
// This can be used for other purposes between calls
//
virtual unsigned getCallAddressReg() const = 0;
// Returns the register containing the return address.
//It should be made sure that this
// register contains the return value when a return instruction is reached.
//
virtual unsigned getReturnAddressReg() const = 0;
// Each register class has a seperate space for register IDs. To convert
// a regId in a register class to a common Id, or vice versa,
// we use the folloing methods.
//
virtual int getUnifiedRegNum(unsigned regClassID, int reg) const = 0;
virtual int getClassRegNum(int unifiedRegNum, unsigned& regClassID) const =0;
// Returns the assembly-language name of the specified machine register.
virtual const char * const getUnifiedRegName(int UnifiedRegNum) const = 0;
// The following 4 methods are used to find the RegType (a target-specific
// enum) for a reg class and a given primitive type, a LiveRange, a Value,
// or a particular machine register.
// The fifth function gives the reg class of the given RegType.
//
virtual int getRegType(unsigned regClassID, const Type* type) const = 0;
virtual int getRegType(const LiveRange *LR) const = 0;
virtual int getRegType(const Value *Val) const = 0;
virtual int getRegType(int unifiedRegNum) const = 0;
// The following methods are used to get the frame/stack pointers
//
virtual unsigned getFramePointer() const = 0;
virtual unsigned getStackPointer() const = 0;
// A register can be initialized to an invalid number. That number can
// be obtained using this method.
//
virtual int getInvalidRegNum() const = 0;
// Method for inserting caller saving code. The caller must save all the
// volatile registers across a call based on the calling conventions of
// an architecture. This must insert code for saving and restoring
// such registers on
//
virtual void insertCallerSavingCode(std::vector<MachineInstr*>& instrnsBefore,
std::vector<MachineInstr*>& instrnsAfter,
MachineInstr *MInst,
const BasicBlock *BB,
PhyRegAlloc &PRA) const = 0;
// This method gives the the number of bytes of stack spaceallocated
// to a register when it is spilled to the stack.
//
virtual int getSpilledRegSize(int RegType) const = 0;
};
#endif