llvm/lib/Target/X86/X86InstrInfo.h
Dan Gohman 57c3dac0df Move the GlobalBaseReg field out of X86ISelDAGToDAG.cpp
and X86FastISel.cpp into X86MachineFunction.h, so that it
can be shared, instead of having each selector keep track
of its own.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56825 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-30 00:58:23 +00:00

433 lines
18 KiB
C++

//===- X86InstrInfo.h - X86 Instruction Information ------------*- C++ -*- ===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the X86 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#ifndef X86INSTRUCTIONINFO_H
#define X86INSTRUCTIONINFO_H
#include "llvm/Target/TargetInstrInfo.h"
#include "X86.h"
#include "X86RegisterInfo.h"
#include "llvm/ADT/IndexedMap.h"
#include "llvm/Target/TargetRegisterInfo.h"
namespace llvm {
class X86RegisterInfo;
class X86TargetMachine;
namespace X86 {
// X86 specific condition code. These correspond to X86_*_COND in
// X86InstrInfo.td. They must be kept in synch.
enum CondCode {
COND_A = 0,
COND_AE = 1,
COND_B = 2,
COND_BE = 3,
COND_E = 4,
COND_G = 5,
COND_GE = 6,
COND_L = 7,
COND_LE = 8,
COND_NE = 9,
COND_NO = 10,
COND_NP = 11,
COND_NS = 12,
COND_O = 13,
COND_P = 14,
COND_S = 15,
COND_INVALID
};
// Turn condition code into conditional branch opcode.
unsigned GetCondBranchFromCond(CondCode CC);
/// GetOppositeBranchCondition - Return the inverse of the specified cond,
/// e.g. turning COND_E to COND_NE.
CondCode GetOppositeBranchCondition(X86::CondCode CC);
}
/// X86II - This namespace holds all of the target specific flags that
/// instruction info tracks.
///
namespace X86II {
enum {
//===------------------------------------------------------------------===//
// Instruction types. These are the standard/most common forms for X86
// instructions.
//
// PseudoFrm - This represents an instruction that is a pseudo instruction
// or one that has not been implemented yet. It is illegal to code generate
// it, but tolerated for intermediate implementation stages.
Pseudo = 0,
/// Raw - This form is for instructions that don't have any operands, so
/// they are just a fixed opcode value, like 'leave'.
RawFrm = 1,
/// AddRegFrm - This form is used for instructions like 'push r32' that have
/// their one register operand added to their opcode.
AddRegFrm = 2,
/// MRMDestReg - This form is used for instructions that use the Mod/RM byte
/// to specify a destination, which in this case is a register.
///
MRMDestReg = 3,
/// MRMDestMem - This form is used for instructions that use the Mod/RM byte
/// to specify a destination, which in this case is memory.
///
MRMDestMem = 4,
/// MRMSrcReg - This form is used for instructions that use the Mod/RM byte
/// to specify a source, which in this case is a register.
///
MRMSrcReg = 5,
/// MRMSrcMem - This form is used for instructions that use the Mod/RM byte
/// to specify a source, which in this case is memory.
///
MRMSrcMem = 6,
/// MRM[0-7][rm] - These forms are used to represent instructions that use
/// a Mod/RM byte, and use the middle field to hold extended opcode
/// information. In the intel manual these are represented as /0, /1, ...
///
// First, instructions that operate on a register r/m operand...
MRM0r = 16, MRM1r = 17, MRM2r = 18, MRM3r = 19, // Format /0 /1 /2 /3
MRM4r = 20, MRM5r = 21, MRM6r = 22, MRM7r = 23, // Format /4 /5 /6 /7
// Next, instructions that operate on a memory r/m operand...
MRM0m = 24, MRM1m = 25, MRM2m = 26, MRM3m = 27, // Format /0 /1 /2 /3
MRM4m = 28, MRM5m = 29, MRM6m = 30, MRM7m = 31, // Format /4 /5 /6 /7
// MRMInitReg - This form is used for instructions whose source and
// destinations are the same register.
MRMInitReg = 32,
FormMask = 63,
//===------------------------------------------------------------------===//
// Actual flags...
// OpSize - Set if this instruction requires an operand size prefix (0x66),
// which most often indicates that the instruction operates on 16 bit data
// instead of 32 bit data.
OpSize = 1 << 6,
// AsSize - Set if this instruction requires an operand size prefix (0x67),
// which most often indicates that the instruction address 16 bit address
// instead of 32 bit address (or 32 bit address in 64 bit mode).
AdSize = 1 << 7,
//===------------------------------------------------------------------===//
// Op0Mask - There are several prefix bytes that are used to form two byte
// opcodes. These are currently 0x0F, 0xF3, and 0xD8-0xDF. This mask is
// used to obtain the setting of this field. If no bits in this field is
// set, there is no prefix byte for obtaining a multibyte opcode.
//
Op0Shift = 8,
Op0Mask = 0xF << Op0Shift,
// TB - TwoByte - Set if this instruction has a two byte opcode, which
// starts with a 0x0F byte before the real opcode.
TB = 1 << Op0Shift,
// REP - The 0xF3 prefix byte indicating repetition of the following
// instruction.
REP = 2 << Op0Shift,
// D8-DF - These escape opcodes are used by the floating point unit. These
// values must remain sequential.
D8 = 3 << Op0Shift, D9 = 4 << Op0Shift,
DA = 5 << Op0Shift, DB = 6 << Op0Shift,
DC = 7 << Op0Shift, DD = 8 << Op0Shift,
DE = 9 << Op0Shift, DF = 10 << Op0Shift,
// XS, XD - These prefix codes are for single and double precision scalar
// floating point operations performed in the SSE registers.
XD = 11 << Op0Shift, XS = 12 << Op0Shift,
// T8, TA - Prefix after the 0x0F prefix.
T8 = 13 << Op0Shift, TA = 14 << Op0Shift,
//===------------------------------------------------------------------===//
// REX_W - REX prefixes are instruction prefixes used in 64-bit mode.
// They are used to specify GPRs and SSE registers, 64-bit operand size,
// etc. We only cares about REX.W and REX.R bits and only the former is
// statically determined.
//
REXShift = 12,
REX_W = 1 << REXShift,
//===------------------------------------------------------------------===//
// This three-bit field describes the size of an immediate operand. Zero is
// unused so that we can tell if we forgot to set a value.
ImmShift = 13,
ImmMask = 7 << ImmShift,
Imm8 = 1 << ImmShift,
Imm16 = 2 << ImmShift,
Imm32 = 3 << ImmShift,
Imm64 = 4 << ImmShift,
//===------------------------------------------------------------------===//
// FP Instruction Classification... Zero is non-fp instruction.
// FPTypeMask - Mask for all of the FP types...
FPTypeShift = 16,
FPTypeMask = 7 << FPTypeShift,
// NotFP - The default, set for instructions that do not use FP registers.
NotFP = 0 << FPTypeShift,
// ZeroArgFP - 0 arg FP instruction which implicitly pushes ST(0), f.e. fld0
ZeroArgFP = 1 << FPTypeShift,
// OneArgFP - 1 arg FP instructions which implicitly read ST(0), such as fst
OneArgFP = 2 << FPTypeShift,
// OneArgFPRW - 1 arg FP instruction which implicitly read ST(0) and write a
// result back to ST(0). For example, fcos, fsqrt, etc.
//
OneArgFPRW = 3 << FPTypeShift,
// TwoArgFP - 2 arg FP instructions which implicitly read ST(0), and an
// explicit argument, storing the result to either ST(0) or the implicit
// argument. For example: fadd, fsub, fmul, etc...
TwoArgFP = 4 << FPTypeShift,
// CompareFP - 2 arg FP instructions which implicitly read ST(0) and an
// explicit argument, but have no destination. Example: fucom, fucomi, ...
CompareFP = 5 << FPTypeShift,
// CondMovFP - "2 operand" floating point conditional move instructions.
CondMovFP = 6 << FPTypeShift,
// SpecialFP - Special instruction forms. Dispatch by opcode explicitly.
SpecialFP = 7 << FPTypeShift,
// Lock prefix
LOCKShift = 19,
LOCK = 1 << LOCKShift,
// Bits 20 -> 23 are unused
OpcodeShift = 24,
OpcodeMask = 0xFF << OpcodeShift
};
}
inline static bool isScale(const MachineOperand &MO) {
return MO.isImmediate() &&
(MO.getImm() == 1 || MO.getImm() == 2 ||
MO.getImm() == 4 || MO.getImm() == 8);
}
inline static bool isMem(const MachineInstr *MI, unsigned Op) {
if (MI->getOperand(Op).isFrameIndex()) return true;
return Op+4 <= MI->getNumOperands() &&
MI->getOperand(Op ).isRegister() && isScale(MI->getOperand(Op+1)) &&
MI->getOperand(Op+2).isRegister() &&
(MI->getOperand(Op+3).isImmediate() ||
MI->getOperand(Op+3).isGlobalAddress() ||
MI->getOperand(Op+3).isConstantPoolIndex() ||
MI->getOperand(Op+3).isJumpTableIndex());
}
class X86InstrInfo : public TargetInstrInfoImpl {
X86TargetMachine &TM;
const X86RegisterInfo RI;
/// RegOp2MemOpTable2Addr, RegOp2MemOpTable0, RegOp2MemOpTable1,
/// RegOp2MemOpTable2 - Load / store folding opcode maps.
///
DenseMap<unsigned*, unsigned> RegOp2MemOpTable2Addr;
DenseMap<unsigned*, unsigned> RegOp2MemOpTable0;
DenseMap<unsigned*, unsigned> RegOp2MemOpTable1;
DenseMap<unsigned*, unsigned> RegOp2MemOpTable2;
/// MemOp2RegOpTable - Load / store unfolding opcode map.
///
DenseMap<unsigned*, std::pair<unsigned, unsigned> > MemOp2RegOpTable;
public:
explicit X86InstrInfo(X86TargetMachine &tm);
/// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As
/// such, whenever a client has an instance of instruction info, it should
/// always be able to get register info as well (through this method).
///
virtual const X86RegisterInfo &getRegisterInfo() const { return RI; }
// Return true if the instruction is a register to register move and
// leave the source and dest operands in the passed parameters.
//
bool isMoveInstr(const MachineInstr& MI, unsigned& sourceReg,
unsigned& destReg) const;
unsigned isLoadFromStackSlot(MachineInstr *MI, int &FrameIndex) const;
unsigned isStoreToStackSlot(MachineInstr *MI, int &FrameIndex) const;
bool isReallyTriviallyReMaterializable(const MachineInstr *MI) const;
void reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
unsigned DestReg, const MachineInstr *Orig) const;
bool isInvariantLoad(MachineInstr *MI) const;
/// convertToThreeAddress - This method must be implemented by targets that
/// set the M_CONVERTIBLE_TO_3_ADDR flag. When this flag is set, the target
/// may be able to convert a two-address instruction into a true
/// three-address instruction on demand. This allows the X86 target (for
/// example) to convert ADD and SHL instructions into LEA instructions if they
/// would require register copies due to two-addressness.
///
/// This method returns a null pointer if the transformation cannot be
/// performed, otherwise it returns the new instruction.
///
virtual MachineInstr *convertToThreeAddress(MachineFunction::iterator &MFI,
MachineBasicBlock::iterator &MBBI,
LiveVariables *LV) const;
/// commuteInstruction - We have a few instructions that must be hacked on to
/// commute them.
///
virtual MachineInstr *commuteInstruction(MachineInstr *MI, bool NewMI) const;
// Branch analysis.
virtual bool isUnpredicatedTerminator(const MachineInstr* MI) const;
virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond) const;
virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const;
virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond) const;
virtual bool copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC) const;
virtual void storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, bool isKill, int FrameIndex,
const TargetRegisterClass *RC) const;
virtual void storeRegToAddr(MachineFunction &MF, unsigned SrcReg, bool isKill,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const;
virtual void loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIndex,
const TargetRegisterClass *RC) const;
virtual void loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const;
virtual bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI) const;
virtual bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI) const;
/// foldMemoryOperand - If this target supports it, fold a load or store of
/// the specified stack slot into the specified machine instruction for the
/// specified operand(s). If this is possible, the target should perform the
/// folding and return true, otherwise it should return false. If it folds
/// the instruction, it is likely that the MachineInstruction the iterator
/// references has been changed.
virtual MachineInstr* foldMemoryOperand(MachineFunction &MF,
MachineInstr* MI,
SmallVectorImpl<unsigned> &Ops,
int FrameIndex) const;
/// foldMemoryOperand - Same as the previous version except it allows folding
/// of any load and store from / to any address, not just from a specific
/// stack slot.
virtual MachineInstr* foldMemoryOperand(MachineFunction &MF,
MachineInstr* MI,
SmallVectorImpl<unsigned> &Ops,
MachineInstr* LoadMI) const;
/// canFoldMemoryOperand - Returns true if the specified load / store is
/// folding is possible.
virtual bool canFoldMemoryOperand(MachineInstr*, SmallVectorImpl<unsigned> &) const;
/// unfoldMemoryOperand - Separate a single instruction which folded a load or
/// a store or a load and a store into two or more instruction. If this is
/// possible, returns true as well as the new instructions by reference.
virtual bool unfoldMemoryOperand(MachineFunction &MF, MachineInstr *MI,
unsigned Reg, bool UnfoldLoad, bool UnfoldStore,
SmallVectorImpl<MachineInstr*> &NewMIs) const;
virtual bool unfoldMemoryOperand(SelectionDAG &DAG, SDNode *N,
SmallVectorImpl<SDNode*> &NewNodes) const;
/// getOpcodeAfterMemoryUnfold - Returns the opcode of the would be new
/// instruction after load / store are unfolded from an instruction of the
/// specified opcode. It returns zero if the specified unfolding is not
/// possible.
virtual unsigned getOpcodeAfterMemoryUnfold(unsigned Opc,
bool UnfoldLoad, bool UnfoldStore) const;
virtual bool BlockHasNoFallThrough(MachineBasicBlock &MBB) const;
virtual
bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const;
const TargetRegisterClass *getPointerRegClass() const;
// getBaseOpcodeFor - This function returns the "base" X86 opcode for the
// specified machine instruction.
//
unsigned char getBaseOpcodeFor(const TargetInstrDesc *TID) const {
return TID->TSFlags >> X86II::OpcodeShift;
}
unsigned char getBaseOpcodeFor(unsigned Opcode) const {
return getBaseOpcodeFor(&get(Opcode));
}
static bool isX86_64NonExtLowByteReg(unsigned reg) {
return (reg == X86::SPL || reg == X86::BPL ||
reg == X86::SIL || reg == X86::DIL);
}
static unsigned sizeOfImm(const TargetInstrDesc *Desc);
static unsigned getX86RegNum(unsigned RegNo);
static bool isX86_64ExtendedReg(const MachineOperand &MO);
static unsigned determineREX(const MachineInstr &MI);
/// GetInstSize - Returns the size of the specified MachineInstr.
///
virtual unsigned GetInstSizeInBytes(const MachineInstr *MI) const;
/// getGlobalBaseReg - Return a virtual register initialized with the
/// the global base register value. Output instructions required to
/// initialize the register in the function entry block, if necessary.
///
unsigned getGlobalBaseReg(MachineFunction *MF) const;
private:
MachineInstr* foldMemoryOperand(MachineFunction &MF,
MachineInstr* MI,
unsigned OpNum,
SmallVector<MachineOperand,4> &MOs) const;
};
} // End llvm namespace
#endif