llvm-6502/include/llvm/CodeGen/MachineInstr.h
2001-10-13 07:18:40 +00:00

510 lines
15 KiB
C++

// $Id$ -*-c++-*-
//***************************************************************************
// File:
// MachineInstr.h
//
// Purpose:
//
//
// Strategy:
//
// History:
// 7/2/01 - Vikram Adve - Created
//**************************************************************************/
#ifndef LLVM_CODEGEN_MACHINEINSTR_H
#define LLVM_CODEGEN_MACHINEINSTR_H
#include <iterator>
#include "llvm/CodeGen/InstrForest.h"
#include "llvm/Support/DataTypes.h"
#include "llvm/Support/NonCopyable.h"
#include "llvm/Target/MachineInstrInfo.h"
template<class _MI, class _V> class ValOpIterator;
//---------------------------------------------------------------------------
// 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.
//
//---------------------------------------------------------------------------
class MachineOperand {
public:
enum MachineOperandType {
MO_VirtualRegister, // virtual register for *value
MO_MachineRegister, // pre-assigned machine register `regNum'
MO_CCRegister,
MO_SignExtendedImmed,
MO_UnextendedImmed,
MO_PCRelativeDisp,
};
private:
MachineOperandType opType;
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.
int64_t immedVal; // constant value for an explicit constant
};
unsigned regNum; // register number for an explicit register
// will be set for a value after reg allocation
bool isDef; // is this a defition for the value
public:
/*ctor*/ MachineOperand ();
/*ctor*/ MachineOperand (MachineOperandType operandType,
Value* _val);
/*copy ctor*/ MachineOperand (const MachineOperand&);
/*dtor*/ ~MachineOperand () {}
// Accessor methods. Caller is responsible for checking the
// operand type before invoking the corresponding accessor.
//
inline MachineOperandType getOperandType () const {
return opType;
}
inline Value* getVRegValue () const {
assert(opType == MO_VirtualRegister || opType == MO_CCRegister ||
opType == MO_PCRelativeDisp);
return value;
}
inline unsigned int getMachineRegNum() const {
assert(opType == MO_MachineRegister);
return regNum;
}
inline int64_t getImmedValue () const {
assert(opType >= MO_SignExtendedImmed || opType <= MO_PCRelativeDisp);
return immedVal;
}
inline bool opIsDef () const {
return isDef;
}
public:
friend ostream& operator<<(ostream& os, const MachineOperand& mop);
private:
// These functions are provided so that a vector of operands can be
// statically allocated and individual ones can be initialized later.
// Give class MachineInstr gets access to these functions.
//
void Initialize (MachineOperandType operandType,
Value* _val);
void InitializeConst (MachineOperandType operandType,
int64_t intValue);
void InitializeReg (unsigned int regNum);
friend class MachineInstr;
friend class ValOpIterator<const MachineInstr, const Value>;
friend class ValOpIterator< MachineInstr, Value>;
public:
// replaces the Value with its corresponding physical register afeter
// register allocation is complete
void setRegForValue(int reg) {
assert(opType == MO_VirtualRegister || opType == MO_CCRegister);
regNum = reg;
}
// used to get the reg number if when one is allocted (must be
// called only after reg alloc)
inline unsigned getAllocatedRegNum() const {
assert(opType == MO_VirtualRegister || opType == MO_CCRegister ||
opType == MO_MachineRegister);
return regNum;
}
};
inline
MachineOperand::MachineOperand()
: opType(MO_VirtualRegister),
immedVal(0),
regNum(0),
isDef(false)
{}
inline
MachineOperand::MachineOperand(MachineOperandType operandType,
Value* _val)
: opType(operandType),
immedVal(0),
value(_val),
isDef(false)
{}
inline
MachineOperand::MachineOperand(const MachineOperand& mo)
: opType(mo.opType),
isDef(false)
{
switch(opType) {
case MO_VirtualRegister:
case MO_CCRegister: value = mo.value; break;
case MO_MachineRegister: regNum = mo.regNum; break;
case MO_SignExtendedImmed:
case MO_UnextendedImmed:
case MO_PCRelativeDisp: immedVal = mo.immedVal; break;
default: assert(0);
}
}
inline void
MachineOperand::Initialize(MachineOperandType operandType,
Value* _val)
{
opType = operandType;
value = _val;
}
inline void
MachineOperand::InitializeConst(MachineOperandType operandType,
int64_t intValue)
{
opType = operandType;
value = NULL;
immedVal = intValue;
}
inline void
MachineOperand::InitializeReg(unsigned int _regNum)
{
opType = MO_MachineRegister;
value = NULL;
regNum = _regNum;
}
//---------------------------------------------------------------------------
// 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.
//
// opCodeMask is used to record variants of an instruction.
// E.g., each branch instruction on SPARC has 2 flags (i.e., 4 variants):
// ANNUL: if 1: Annul delay slot instruction.
// PREDICT-NOT-TAKEN: if 1: predict branch not taken.
// Instead of creating 4 different opcodes for BNZ, we create a single
// opcode and set bits in opCodeMask for each of these flags.
//
// 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 : public NonCopyable {
private:
MachineOpCode opCode;
OpCodeMask opCodeMask; // extra bits for variants of an opcode
vector<MachineOperand> operands;
vector<Value*> implicitRefs; // values implicitly referenced by this
vector<bool> implicitIsDef; // machine instruction (eg, call args)
public:
typedef ValOpIterator<const MachineInstr, const Value> val_op_const_iterator;
typedef ValOpIterator<const MachineInstr, Value> val_op_iterator;
public:
/*ctor*/ MachineInstr (MachineOpCode _opCode,
OpCodeMask _opCodeMask = 0x0);
/*ctor*/ MachineInstr (MachineOpCode _opCode,
unsigned numOperands,
OpCodeMask _opCodeMask = 0x0);
inline ~MachineInstr () {}
const MachineOpCode getOpCode () const { return opCode; }
//
// Information about explicit operands of the instruction
//
unsigned int getNumOperands () const { return operands.size(); }
bool operandIsDefined(unsigned int i) const;
const MachineOperand& getOperand (unsigned int i) const;
MachineOperand& getOperand (unsigned int i);
//
// Information about implicit operands of the instruction
//
unsigned int getNumImplicitRefs() const{return implicitRefs.size();}
bool implicitRefIsDefined(unsigned int i) const;
const Value* getImplicitRef (unsigned int i) const;
Value* getImplicitRef (unsigned int i);
//
// Debugging support
//
void dump (unsigned int indent = 0) const;
public:
friend ostream& operator<<(ostream& os, const MachineInstr& minstr);
friend val_op_const_iterator;
friend val_op_iterator;
public:
// Access to set the operands when building the machine instruction
void SetMachineOperand(unsigned int i,
MachineOperand::MachineOperandType operandType,
Value* _val, bool isDef=false);
void SetMachineOperand(unsigned int i,
MachineOperand::MachineOperandType operandType,
int64_t intValue, bool isDef=false);
void SetMachineOperand(unsigned int i,
unsigned int regNum,
bool isDef=false);
void addImplicitRef (Value* val,
bool isDef=false);
void setImplicitRef (unsigned int i,
Value* val,
bool isDef=false);
};
inline MachineOperand&
MachineInstr::getOperand(unsigned int i)
{
assert(i < operands.size() && "getOperand() out of range!");
return operands[i];
}
inline const MachineOperand&
MachineInstr::getOperand(unsigned int i) const
{
assert(i < operands.size() && "getOperand() out of range!");
return operands[i];
}
inline bool
MachineInstr::operandIsDefined(unsigned int i) const
{
return getOperand(i).opIsDef();
}
inline bool
MachineInstr::implicitRefIsDefined(unsigned int i) const
{
assert(i < implicitIsDef.size() && "operand out of range!");
return implicitIsDef[i];
}
inline const Value*
MachineInstr::getImplicitRef(unsigned int i) const
{
assert(i < implicitRefs.size() && "getImplicitRef() out of range!");
return implicitRefs[i];
}
inline Value*
MachineInstr::getImplicitRef(unsigned int i)
{
assert(i < implicitRefs.size() && "getImplicitRef() out of range!");
return implicitRefs[i];
}
inline void
MachineInstr::addImplicitRef(Value* val,
bool isDef)
{
implicitRefs.push_back(val);
implicitIsDef.push_back(isDef);
}
inline void
MachineInstr::setImplicitRef(unsigned int i,
Value* val,
bool isDef)
{
assert(i < implicitRefs.size() && "setImplicitRef() out of range!");
implicitRefs[i] = val;
implicitIsDef[i] = isDef;
}
template<class _MI, class _V>
class ValOpIterator : public std::forward_iterator<_V, ptrdiff_t> {
private:
unsigned int i;
int resultPos;
_MI* minstr;
inline void skipToNextVal() {
while (i < minstr->getNumOperands() &&
! ((minstr->operands[i].opType == MachineOperand::MO_VirtualRegister
|| minstr->operands[i].opType == MachineOperand::MO_CCRegister)
&& minstr->operands[i].value != NULL))
++i;
}
public:
typedef ValOpIterator<_MI, _V> _Self;
inline ValOpIterator(_MI* _minstr) : i(0), minstr(_minstr) {
resultPos = TargetInstrDescriptors[minstr->opCode].resultPos;
skipToNextVal();
};
inline _V* operator*() const { return minstr->getOperand(i).getVRegValue();}
const MachineOperand & getMachineOperand() const { return minstr->getOperand(i); }
inline _V* operator->() const { return operator*(); }
// inline bool isDef () const { return (((int) i) == resultPos); }
inline bool isDef () const { return minstr->getOperand(i).isDef; }
inline bool done () const { return (i == minstr->getNumOperands()); }
inline _Self& operator++() { i++; skipToNextVal(); return *this; }
inline _Self operator++(int) { _Self tmp = *this; ++*this; return tmp; }
};
//---------------------------------------------------------------------------
// class MachineCodeForVMInstr
//
// Purpose:
// Representation of the sequence of machine instructions created
// for a single VM instruction. Additionally records information
// about hidden and implicit values used by the machine instructions:
// about hidden values used by the machine instructions:
//
// "Temporary values" are intermediate values used in the machine
// instruction sequence, but not in the VM instruction
// Note that such values should be treated as pure SSA values with
// no interpretation of their operands (i.e., as a TmpInstruction
// object which actually represents such a value).
//
// (2) "Implicit uses" are values used in the VM instruction but not in
// the machine instruction sequence
//
//---------------------------------------------------------------------------
class MachineCodeForVMInstr: public vector<MachineInstr*>
{
private:
vector<Value*> tempVec; // used by m/c instr but not VM instr
public:
/*ctor*/ MachineCodeForVMInstr () {}
/*ctor*/ ~MachineCodeForVMInstr ();
const vector<Value*>& getTempValues () const { return tempVec; }
vector<Value*>& getTempValues () { return tempVec; }
void addTempValue (Value* val) { tempVec.push_back(val); }
// dropAllReferences() - This function drops all references within
// temporary (hidden) instructions created in implementing the original
// VM intruction. This ensures there are no remaining "uses" within
// these hidden instructions, before the values of a method are freed.
//
// Make this inline because it has to be called from class Instruction
// and inlining it avoids a serious circurality in link order.
inline void dropAllReferences() {
for (unsigned i=0, N=tempVec.size(); i < N; i++)
if (Instruction *I = dyn_cast<Instruction>(tempVec[i]))
I->dropAllReferences();
}
};
inline
MachineCodeForVMInstr::~MachineCodeForVMInstr()
{
// Free the Value objects created to hold intermediate values
for (unsigned i=0, N=tempVec.size(); i < N; i++)
delete tempVec[i];
// Free the MachineInstr objects allocated, if any.
for (unsigned i=0, N=this->size(); i < N; i++)
delete (*this)[i];
}
//---------------------------------------------------------------------------
// class MachineCodeForBasicBlock
//
// Purpose:
// Representation of the sequence of machine instructions created
// for a basic block.
//---------------------------------------------------------------------------
class MachineCodeForBasicBlock: public vector<MachineInstr*> {
public:
typedef vector<MachineInstr*>::iterator iterator;
typedef vector<const MachineInstr*>::const_iterator const_iterator;
};
//---------------------------------------------------------------------------
// Debugging Support
//---------------------------------------------------------------------------
ostream& operator<< (ostream& os, const MachineInstr& minstr);
ostream& operator<< (ostream& os, const MachineOperand& mop);
void PrintMachineInstructions(const Method *method);
//**************************************************************************/
#endif