llvm-6502/include/llvm/CodeGen/MachineInstr.h
2003-12-14 13:30:19 +00:00

725 lines
26 KiB
C++

//===-- llvm/CodeGen/MachineInstr.h - MachineInstr class --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declaration of the MachineInstr class, which is the
// basic representation for all target dependent machine instructions used by
// the back end.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_MACHINEINSTR_H
#define LLVM_CODEGEN_MACHINEINSTR_H
#include "llvm/Target/MRegisterInfo.h"
#include "Support/Annotation.h"
#include "Support/iterator"
namespace llvm {
class Value;
class Function;
class MachineBasicBlock;
class TargetMachine;
class GlobalValue;
typedef int MachineOpCode;
//===----------------------------------------------------------------------===//
/// Special flags on instructions that modify the opcode.
/// These flags are unused for now, but having them enforces that some
/// changes will be needed if they are used.
///
enum MachineOpCodeFlags {
AnnulFlag, /// 1 if annul bit is set on a branch
PredTakenFlag, /// 1 if branch should be predicted taken
PredNotTakenFlag /// 1 if branch should be predicted not taken
};
//===----------------------------------------------------------------------===//
/// MOTy - MachineOperandType - This namespace contains an enum that describes
/// how the machine operand is used by the instruction: is it read, defined, or
/// both? Note that the MachineInstr/Operator class currently uses bool
/// arguments to represent this information instead of an enum. Eventually this
/// should change over to use this _easier to read_ representation instead.
///
namespace MOTy {
enum UseType {
Use, /// This machine operand is only read by the instruction
Def, /// This machine operand is only written by the instruction
UseAndDef /// This machine operand is read AND written
};
}
//===----------------------------------------------------------------------===//
// class MachineOperand
//
// Purpose:
// Representation of each machine instruction operand.
// This class is designed so that you can allocate a vector of operands
// first and initialize each one later.
//
// E.g, for this VM instruction:
// ptr = alloca type, numElements
// we generate 2 machine instructions on the SPARC:
//
// mul Constant, Numelements -> Reg
// add %sp, Reg -> Ptr
//
// Each instruction has 3 operands, listed above. Of those:
// - Reg, NumElements, and Ptr are of operand type MO_Register.
// - Constant is of operand type MO_SignExtendedImmed on the SPARC.
//
// For the register operands, the virtual register type is as follows:
//
// - Reg will be of virtual register type MO_MInstrVirtualReg. The field
// MachineInstr* minstr will point to the instruction that computes reg.
//
// - %sp will be of virtual register type MO_MachineReg.
// The field regNum identifies the machine register.
//
// - NumElements will be of virtual register type MO_VirtualReg.
// The field Value* value identifies the value.
//
// - Ptr will also be of virtual register type MO_VirtualReg.
// Again, the field Value* value identifies the value.
//
//===----------------------------------------------------------------------===//
struct MachineOperand {
enum MachineOperandType {
MO_VirtualRegister, // virtual register for *value
MO_MachineRegister, // pre-assigned machine register `regNum'
MO_CCRegister,
MO_SignExtendedImmed,
MO_UnextendedImmed,
MO_PCRelativeDisp,
MO_MachineBasicBlock, // MachineBasicBlock reference
MO_FrameIndex, // Abstract Stack Frame Index
MO_ConstantPoolIndex, // Address of indexed Constant in Constant Pool
MO_ExternalSymbol, // Name of external global symbol
MO_GlobalAddress, // Address of a global value
};
private:
// Bit fields of the flags variable used for different operand properties
enum {
DEFFLAG = 0x01, // this is a def of the operand
USEFLAG = 0x02, // this is a use of the operand
HIFLAG32 = 0x04, // operand is %hi32(value_or_immedVal)
LOFLAG32 = 0x08, // operand is %lo32(value_or_immedVal)
HIFLAG64 = 0x10, // operand is %hi64(value_or_immedVal)
LOFLAG64 = 0x20, // operand is %lo64(value_or_immedVal)
PCRELATIVE = 0x40, // Operand is relative to PC, not a global address
};
private:
union {
Value* value; // BasicBlockVal for a label operand.
// ConstantVal for a non-address immediate.
// Virtual register for an SSA operand,
// including hidden operands required for
// the generated machine code.
// LLVM global for MO_GlobalAddress.
int64_t immedVal; // Constant value for an explicit constant
MachineBasicBlock *MBB; // For MO_MachineBasicBlock type
std::string *SymbolName; // For MO_ExternalSymbol type
};
char flags; // see bit field definitions above
MachineOperandType opType:8; // Pack into 8 bits efficiently after flags.
int regNum; // register number for an explicit register
// will be set for a value after reg allocation
private:
MachineOperand()
: immedVal(0),
flags(0),
opType(MO_VirtualRegister),
regNum(-1) {}
MachineOperand(int64_t ImmVal, MachineOperandType OpTy)
: immedVal(ImmVal),
flags(0),
opType(OpTy),
regNum(-1) {}
MachineOperand(int Reg, MachineOperandType OpTy, MOTy::UseType UseTy)
: immedVal(0),
opType(OpTy),
regNum(Reg) {
switch (UseTy) {
case MOTy::Use: flags = USEFLAG; break;
case MOTy::Def: flags = DEFFLAG; break;
case MOTy::UseAndDef: flags = DEFFLAG | USEFLAG; break;
default: assert(0 && "Invalid value for UseTy!");
}
}
MachineOperand(Value *V, MachineOperandType OpTy, MOTy::UseType UseTy,
bool isPCRelative = false)
: value(V), opType(OpTy), regNum(-1) {
switch (UseTy) {
case MOTy::Use: flags = USEFLAG; break;
case MOTy::Def: flags = DEFFLAG; break;
case MOTy::UseAndDef: flags = DEFFLAG | USEFLAG; break;
default: assert(0 && "Invalid value for UseTy!");
}
if (isPCRelative) flags |= PCRELATIVE;
}
MachineOperand(MachineBasicBlock *mbb)
: MBB(mbb), flags(0), opType(MO_MachineBasicBlock), regNum(-1) {}
MachineOperand(const std::string &SymName, bool isPCRelative)
: SymbolName(new std::string(SymName)), flags(isPCRelative ? PCRELATIVE :0),
opType(MO_ExternalSymbol), regNum(-1) {}
public:
MachineOperand(const MachineOperand &M) : immedVal(M.immedVal),
flags(M.flags),
opType(M.opType),
regNum(M.regNum) {
if (isExternalSymbol())
SymbolName = new std::string(M.getSymbolName());
}
~MachineOperand() {
if (isExternalSymbol())
delete SymbolName;
}
const MachineOperand &operator=(const MachineOperand &MO) {
if (isExternalSymbol()) // if old operand had a symbol name,
delete SymbolName; // release old memory
immedVal = MO.immedVal;
flags = MO.flags;
opType = MO.opType;
regNum = MO.regNum;
if (isExternalSymbol())
SymbolName = new std::string(MO.getSymbolName());
return *this;
}
// Accessor methods. Caller is responsible for checking the
// operand type before invoking the corresponding accessor.
//
MachineOperandType getType() const { return opType; }
/// isPCRelative - This returns the value of the PCRELATIVE flag, which
/// indicates whether this operand should be emitted as a PC relative value
/// instead of a global address. This is used for operands of the forms:
/// MachineBasicBlock, GlobalAddress, ExternalSymbol
///
bool isPCRelative() const { return (flags & PCRELATIVE) != 0; }
// This is to finally stop caring whether we have a virtual or machine
// register -- an easier interface is to simply call both virtual and machine
// registers essentially the same, yet be able to distinguish when
// necessary. Thus the instruction selector can just add registers without
// abandon, and the register allocator won't be confused.
bool isVirtualRegister() const {
return (opType == MO_VirtualRegister || opType == MO_MachineRegister)
&& regNum >= MRegisterInfo::FirstVirtualRegister;
}
bool isPhysicalRegister() const {
return (opType == MO_VirtualRegister || opType == MO_MachineRegister)
&& (unsigned)regNum < MRegisterInfo::FirstVirtualRegister;
}
bool isRegister() const { return isVirtualRegister() || isPhysicalRegister();}
bool isMachineRegister() const { return !isVirtualRegister(); }
bool isMachineBasicBlock() const { return opType == MO_MachineBasicBlock; }
bool isPCRelativeDisp() const { return opType == MO_PCRelativeDisp; }
bool isImmediate() const {
return opType == MO_SignExtendedImmed || opType == MO_UnextendedImmed;
}
bool isFrameIndex() const { return opType == MO_FrameIndex; }
bool isConstantPoolIndex() const { return opType == MO_ConstantPoolIndex; }
bool isGlobalAddress() const { return opType == MO_GlobalAddress; }
bool isExternalSymbol() const { return opType == MO_ExternalSymbol; }
Value* getVRegValue() const {
assert(opType == MO_VirtualRegister || opType == MO_CCRegister ||
isPCRelativeDisp());
return value;
}
Value* getVRegValueOrNull() const {
return (opType == MO_VirtualRegister || opType == MO_CCRegister ||
isPCRelativeDisp()) ? value : NULL;
}
int getMachineRegNum() const {
assert(opType == MO_MachineRegister);
return regNum;
}
int64_t getImmedValue() const { assert(isImmediate()); return immedVal; }
void setImmedValue(int64_t ImmVal) { assert(isImmediate()); immedVal=ImmVal; }
MachineBasicBlock *getMachineBasicBlock() const {
assert(isMachineBasicBlock() && "Can't get MBB in non-MBB operand!");
return MBB;
}
int getFrameIndex() const { assert(isFrameIndex()); return immedVal; }
unsigned getConstantPoolIndex() const {
assert(isConstantPoolIndex());
return immedVal;
}
GlobalValue *getGlobal() const {
assert(isGlobalAddress());
return (GlobalValue*)value;
}
const std::string &getSymbolName() const {
assert(isExternalSymbol());
return *SymbolName;
}
bool isUse () const { return flags & USEFLAG; }
bool isDef () const { return flags & DEFFLAG; }
bool isHiBits32 () const { return flags & HIFLAG32; }
bool isLoBits32 () const { return flags & LOFLAG32; }
bool isHiBits64 () const { return flags & HIFLAG64; }
bool isLoBits64 () const { return flags & LOFLAG64; }
// used to check if a machine register has been allocated to this operand
bool hasAllocatedReg() const {
return (regNum >= 0 &&
(opType == MO_VirtualRegister || opType == MO_CCRegister ||
opType == MO_MachineRegister));
}
// used to get the reg number if when one is allocated
int getAllocatedRegNum() const {
assert(hasAllocatedReg());
return regNum;
}
// ********** TODO: get rid of this duplicate code! ***********
unsigned getReg() const {
return getAllocatedRegNum();
}
void setReg(unsigned Reg) {
assert(hasAllocatedReg() && "This operand cannot have a register number!");
regNum = Reg;
}
friend std::ostream& operator<<(std::ostream& os, const MachineOperand& mop);
private:
// Construction methods needed for fine-grain control.
// These must be accessed via coresponding methods in MachineInstr.
void markHi32() { flags |= HIFLAG32; }
void markLo32() { flags |= LOFLAG32; }
void markHi64() { flags |= HIFLAG64; }
void markLo64() { flags |= LOFLAG64; }
// Replaces the Value with its corresponding physical register after
// register allocation is complete
void setRegForValue(int reg) {
assert(opType == MO_VirtualRegister || opType == MO_CCRegister ||
opType == MO_MachineRegister);
regNum = reg;
}
friend class MachineInstr;
};
//===----------------------------------------------------------------------===//
// class MachineInstr
//
// Purpose:
// Representation of each machine instruction.
//
// MachineOpCode must be an enum, defined separately for each target.
// E.g., It is defined in SparcInstructionSelection.h for the SPARC.
//
// There are 2 kinds of operands:
//
// (1) Explicit operands of the machine instruction in vector operands[]
//
// (2) "Implicit operands" are values implicitly used or defined by the
// machine instruction, such as arguments to a CALL, return value of
// a CALL (if any), and return value of a RETURN.
//===----------------------------------------------------------------------===//
class MachineInstr {
int opCode; // the opcode
unsigned opCodeFlags; // flags modifying instrn behavior
std::vector<MachineOperand> operands; // the operands
unsigned numImplicitRefs; // number of implicit operands
// OperandComplete - Return true if it's illegal to add a new operand
bool OperandsComplete() const;
MachineInstr(const MachineInstr &); // DO NOT IMPLEMENT
void operator=(const MachineInstr&); // DO NOT IMPLEMENT
public:
MachineInstr(int Opcode, unsigned numOperands);
/// MachineInstr ctor - This constructor only does a _reserve_ of the
/// operands, not a resize for them. It is expected that if you use this that
/// you call add* methods below to fill up the operands, instead of the Set
/// methods. Eventually, the "resizing" ctors will be phased out.
///
MachineInstr(int Opcode, unsigned numOperands, bool XX, bool YY);
/// MachineInstr ctor - Work exactly the same as the ctor above, except that
/// the MachineInstr is created and added to the end of the specified basic
/// block.
///
MachineInstr(MachineBasicBlock *MBB, int Opcode, unsigned numOps);
// The opcode.
//
const int getOpcode() const { return opCode; }
const int getOpCode() const { return opCode; }
// Opcode flags.
//
unsigned getOpCodeFlags() const { return opCodeFlags; }
//
// Access to explicit operands of the instruction
//
unsigned getNumOperands() const { return operands.size() - numImplicitRefs; }
const MachineOperand& getOperand(unsigned i) const {
assert(i < getNumOperands() && "getOperand() out of range!");
return operands[i];
}
MachineOperand& getOperand(unsigned i) {
assert(i < getNumOperands() && "getOperand() out of range!");
return operands[i];
}
//
// Access to explicit or implicit operands of the instruction
// This returns the i'th entry in the operand vector.
// That represents the i'th explicit operand or the (i-N)'th implicit operand,
// depending on whether i < N or i >= N.
//
const MachineOperand& getExplOrImplOperand(unsigned i) const {
assert(i < operands.size() && "getExplOrImplOperand() out of range!");
return (i < getNumOperands()? getOperand(i)
: getImplicitOp(i - getNumOperands()));
}
//
// Access to implicit operands of the instruction
//
unsigned getNumImplicitRefs() const{ return numImplicitRefs; }
MachineOperand& getImplicitOp(unsigned i) {
assert(i < numImplicitRefs && "implicit ref# out of range!");
return operands[i + operands.size() - numImplicitRefs];
}
const MachineOperand& getImplicitOp(unsigned i) const {
assert(i < numImplicitRefs && "implicit ref# out of range!");
return operands[i + operands.size() - numImplicitRefs];
}
Value* getImplicitRef(unsigned i) {
return getImplicitOp(i).getVRegValue();
}
const Value* getImplicitRef(unsigned i) const {
return getImplicitOp(i).getVRegValue();
}
void addImplicitRef(Value* V, bool isDef = false, bool isDefAndUse = false) {
++numImplicitRefs;
addRegOperand(V, isDef, isDefAndUse);
}
void setImplicitRef(unsigned i, Value* V) {
assert(i < getNumImplicitRefs() && "setImplicitRef() out of range!");
SetMachineOperandVal(i + getNumOperands(),
MachineOperand::MO_VirtualRegister, V);
}
//
// Debugging support
//
void print(std::ostream &OS, const TargetMachine &TM) const;
void dump() const;
friend std::ostream& operator<<(std::ostream& os, const MachineInstr& minstr);
//
// Define iterators to access the Value operands of the Machine Instruction.
// Note that these iterators only enumerate the explicit operands.
// begin() and end() are defined to produce these iterators...
//
template<class _MI, class _V> class ValOpIterator;
typedef ValOpIterator<const MachineInstr*,const Value*> const_val_op_iterator;
typedef ValOpIterator< MachineInstr*, Value*> val_op_iterator;
//===--------------------------------------------------------------------===//
// Accessors to add operands when building up machine instructions
//
/// addRegOperand - Add a MO_VirtualRegister operand to the end of the
/// operands list...
///
void addRegOperand(Value *V, bool isDef, bool isDefAndUse=false) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(V, MachineOperand::MO_VirtualRegister,
!isDef ? MOTy::Use : (isDefAndUse ? MOTy::UseAndDef : MOTy::Def)));
}
void addRegOperand(Value *V, MOTy::UseType UTy = MOTy::Use,
bool isPCRelative = false) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(V, MachineOperand::MO_VirtualRegister,
UTy, isPCRelative));
}
void addCCRegOperand(Value *V, MOTy::UseType UTy = MOTy::Use) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(V, MachineOperand::MO_CCRegister, UTy,
false));
}
/// addRegOperand - Add a symbolic virtual register reference...
///
void addRegOperand(int reg, bool isDef) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(reg, MachineOperand::MO_VirtualRegister,
isDef ? MOTy::Def : MOTy::Use));
}
/// addRegOperand - Add a symbolic virtual register reference...
///
void addRegOperand(int reg, MOTy::UseType UTy = MOTy::Use) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(reg, MachineOperand::MO_VirtualRegister,
UTy));
}
/// addPCDispOperand - Add a PC relative displacement operand to the MI
///
void addPCDispOperand(Value *V) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(V, MachineOperand::MO_PCRelativeDisp,
MOTy::Use));
}
/// addMachineRegOperand - Add a virtual register operand to this MachineInstr
///
void addMachineRegOperand(int reg, bool isDef) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(reg, MachineOperand::MO_MachineRegister,
isDef ? MOTy::Def : MOTy::Use));
}
/// addMachineRegOperand - Add a virtual register operand to this MachineInstr
///
void addMachineRegOperand(int reg, MOTy::UseType UTy = MOTy::Use) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(reg, MachineOperand::MO_MachineRegister,
UTy));
}
/// addZeroExtImmOperand - Add a zero extended constant argument to the
/// machine instruction.
///
void addZeroExtImmOperand(int64_t intValue) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(intValue,
MachineOperand::MO_UnextendedImmed));
}
/// addSignExtImmOperand - Add a zero extended constant argument to the
/// machine instruction.
///
void addSignExtImmOperand(int64_t intValue) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(intValue,
MachineOperand::MO_SignExtendedImmed));
}
void addMachineBasicBlockOperand(MachineBasicBlock *MBB) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(MBB));
}
/// addFrameIndexOperand - Add an abstract frame index to the instruction
///
void addFrameIndexOperand(unsigned Idx) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(Idx, MachineOperand::MO_FrameIndex));
}
/// addConstantPoolndexOperand - Add a constant pool object index to the
/// instruction.
///
void addConstantPoolIndexOperand(unsigned I) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand(I, MachineOperand::MO_ConstantPoolIndex));
}
void addGlobalAddressOperand(GlobalValue *GV, bool isPCRelative) {
assert(!OperandsComplete() &&
"Trying to add an operand to a machine instr that is already done!");
operands.push_back(MachineOperand((Value*)GV,
MachineOperand::MO_GlobalAddress,
MOTy::Use, isPCRelative));
}
/// addExternalSymbolOperand - Add an external symbol operand to this instr
///
void addExternalSymbolOperand(const std::string &SymName, bool isPCRelative) {
operands.push_back(MachineOperand(SymName, isPCRelative));
}
//===--------------------------------------------------------------------===//
// Accessors used to modify instructions in place.
//
// FIXME: Move this stuff to MachineOperand itself!
/// replace - Support to rewrite a machine instruction in place: for now,
/// simply replace() and then set new operands with Set.*Operand methods
/// below.
///
void replace(int Opcode, unsigned numOperands);
/// setOpcode - Replace the opcode of the current instruction with a new one.
///
void setOpcode(unsigned Op) { opCode = Op; }
/// RemoveOperand - Erase an operand from an instruction, leaving it with one
/// fewer operand than it started with.
///
void RemoveOperand(unsigned i) {
operands.erase(operands.begin()+i);
}
// Access to set the operands when building the machine instruction
//
void SetMachineOperandVal (unsigned i,
MachineOperand::MachineOperandType operandType,
Value* V);
void SetMachineOperandConst (unsigned i,
MachineOperand::MachineOperandType operandType,
int64_t intValue);
void SetMachineOperandReg(unsigned i, int regNum);
unsigned substituteValue(const Value* oldVal, Value* newVal,
bool defsOnly, bool notDefsAndUses,
bool& someArgsWereIgnored);
void setOperandHi32(unsigned i) { operands[i].markHi32(); }
void setOperandLo32(unsigned i) { operands[i].markLo32(); }
void setOperandHi64(unsigned i) { operands[i].markHi64(); }
void setOperandLo64(unsigned i) { operands[i].markLo64(); }
// SetRegForOperand -
// SetRegForImplicitRef -
// Mark an explicit or implicit operand with its allocated physical register.
//
void SetRegForOperand(unsigned i, int regNum);
void SetRegForImplicitRef(unsigned i, int regNum);
//
// Iterator to enumerate machine operands.
//
template<class MITy, class VTy>
class ValOpIterator : public forward_iterator<VTy, ptrdiff_t> {
unsigned i;
MITy MI;
void skipToNextVal() {
while (i < MI->getNumOperands() &&
!( (MI->getOperand(i).getType() == MachineOperand::MO_VirtualRegister ||
MI->getOperand(i).getType() == MachineOperand::MO_CCRegister)
&& MI->getOperand(i).getVRegValue() != 0))
++i;
}
inline ValOpIterator(MITy mi, unsigned I) : i(I), MI(mi) {
skipToNextVal();
}
public:
typedef ValOpIterator<MITy, VTy> _Self;
inline VTy operator*() const {
return MI->getOperand(i).getVRegValue();
}
const MachineOperand &getMachineOperand() const { return MI->getOperand(i);}
MachineOperand &getMachineOperand() { return MI->getOperand(i);}
inline VTy operator->() const { return operator*(); }
inline bool isUse() const { return MI->getOperand(i).isUse(); }
inline bool isDef() const { return MI->getOperand(i).isDef(); }
inline _Self& operator++() { i++; skipToNextVal(); return *this; }
inline _Self operator++(int) { _Self tmp = *this; ++*this; return tmp; }
inline bool operator==(const _Self &y) const {
return i == y.i;
}
inline bool operator!=(const _Self &y) const {
return !operator==(y);
}
static _Self begin(MITy MI) {
return _Self(MI, 0);
}
static _Self end(MITy MI) {
return _Self(MI, MI->getNumOperands());
}
};
// define begin() and end()
val_op_iterator begin() { return val_op_iterator::begin(this); }
val_op_iterator end() { return val_op_iterator::end(this); }
const_val_op_iterator begin() const {
return const_val_op_iterator::begin(this);
}
const_val_op_iterator end() const {
return const_val_op_iterator::end(this);
}
};
//===----------------------------------------------------------------------===//
// Debugging Support
std::ostream& operator<<(std::ostream &OS, const MachineInstr &MI);
std::ostream& operator<<(std::ostream &OS, const MachineOperand &MO);
void PrintMachineInstructions(const Function *F);
} // End llvm namespace
#endif