llvm-6502/include/llvm/Target/TargetRegInfo.h
Vikram S. Adve ceb7d2f4f8 Moved insertCallerSavingCode() to PhyRegAlloc and
moved isRegVolatile and modifiedByCall here: they are all
machine independent.  Remove all uses of PhyRegAlloc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7387 91177308-0d34-0410-b5e6-96231b3b80d8
2003-07-29 19:41:23 +00:00

286 lines
11 KiB
C++

//===-- 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/hash_map"
#include <string>
#include <cassert>
class TargetMachine;
class IGNode;
class Type;
class Value;
class LiveRangeInfo;
class Function;
class LiveRange;
class AddedInstrns;
class MachineInstr;
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 marks the registers used for a given register number.
// This defaults to marking a single register but may mark multiple
// registers when a single number denotes paired registers.
//
virtual void markColorsUsed(unsigned RegInClass,
int UserRegType,
int RegTypeWanted,
std::vector<bool> &IsColorUsedArr) const {
assert(RegInClass < NumOfAllRegs && RegInClass < IsColorUsedArr.size());
assert(UserRegType == RegTypeWanted &&
"Default method is probably incorrect for class with multiple types.");
IsColorUsedArr[RegInClass] = true;
}
// This method finds unused registers of the specified register type,
// using the given "used" flag array IsColorUsedArr. It defaults to
// checking a single entry in the array directly, but that can be overridden
// for paired registers and other such silliness.
// It returns -1 if no unused color is found.
//
virtual int findUnusedColor(int RegTypeWanted,
const std::vector<bool> &IsColorUsedArr) const {
// find first unused color in the IsColorUsedArr directly
unsigned NC = this->getNumOfAvailRegs();
assert(IsColorUsedArr.size() >= NC && "Invalid colors-used array");
for (unsigned c = 0; c < NC; c++)
if (!IsColorUsedArr[c])
return c;
return -1;
}
// 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,
const std::vector<bool> &IsColorUsedArr) const = 0;
// Check whether a specific register is volatile, i.e., whether it is not
// preserved across calls
virtual bool isRegVolatile(int Reg) const = 0;
// Check whether a specific register is modified as a side-effect of the
// call instruction itself,
virtual bool modifiedByCall(int Reg) const {return false; }
virtual const char* const getRegName(unsigned 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 {
TargetRegInfo(const TargetRegInfo &); // DO NOT IMPLEMENT
void operator=(const TargetRegInfo &); // DO NOT IMPLEMENT
protected:
// A vector of all machine register classes
//
std::vector<const TargetRegClassInfo *> MachineRegClassArr;
public:
const TargetMachine &target;
// A register can be initialized to an invalid number. That number can
// be obtained using this method.
//
static int getInvalidRegNum() { return -1; }
TargetRegInfo(const TargetMachine& tgt) : target(tgt) { }
virtual ~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 getRegClassIDOfRegType(int regType) const = 0;
unsigned getRegClassIDOfReg(int unifiedRegNum) const {
unsigned classId = 0;
(void) getClassRegNum(unifiedRegNum, classId);
return classId;
}
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,
std::vector<MachineInstr*>& InstrnsBefore,
std::vector<MachineInstr*>& InstrnsAfter) 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;
// Check whether a specific register is volatile, i.e., whether it is not
// preserved across calls
inline virtual bool isRegVolatile(int RegClassID, int Reg) const {
return MachineRegClassArr[RegClassID]->isRegVolatile(Reg);
}
// Check whether a specific register is modified as a side-effect of the
// call instruction itself,
inline virtual bool modifiedByCall(int RegClassID, int Reg) const {
return MachineRegClassArr[RegClassID]->modifiedByCall(Reg);
}
// 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 separate space for register IDs. To convert
// a regId in a register class to a common Id, or vice versa,
// we use the folloing two methods.
//
// This method converts from class reg. number to unified register number.
int getUnifiedRegNum(unsigned regClassID, int reg) const {
if (reg == getInvalidRegNum()) { return getInvalidRegNum(); }
assert(regClassID < getNumOfRegClasses() && "Invalid register class");
int totalRegs = 0;
for (unsigned rcid = 0; rcid < regClassID; ++rcid)
totalRegs += MachineRegClassArr[rcid]->getNumOfAllRegs();
return reg + totalRegs;
}
// This method converts the unified number to the number in its class,
// and returns the class ID in regClassID.
int getClassRegNum(int uRegNum, unsigned& regClassID) const {
if (uRegNum == getInvalidRegNum()) { return getInvalidRegNum(); }
int totalRegs = 0, rcid = 0, NC = getNumOfRegClasses();
while (rcid < NC &&
uRegNum>= totalRegs+(int)MachineRegClassArr[rcid]->getNumOfAllRegs())
{
totalRegs += MachineRegClassArr[rcid]->getNumOfAllRegs();
rcid++;
}
if (rcid == NC) {
assert(0 && "getClassRegNum(): Invalid register number");
return getInvalidRegNum();
}
regClassID = rcid;
return uRegNum - totalRegs;
}
// Returns the assembly-language name of the specified machine register.
//
const char * const getUnifiedRegName(int UnifiedRegNum) const {
unsigned regClassID = getNumOfRegClasses(); // initialize to invalid value
int regNumInClass = getClassRegNum(UnifiedRegNum, regClassID);
return MachineRegClassArr[regClassID]->getRegName(regNumInClass);
}
// Get the register type for a register identified different ways.
// Note that getRegTypeForLR(LR) != getRegTypeForDataType(LR->getType())!
// The reg class of a LR depends both on the Value types in it and whether
// they are CC registers or not (for example).
virtual int getRegTypeForDataType(const Type* type) const = 0;
virtual int getRegTypeForLR(const LiveRange *LR) 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;
// 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