lib/Target/X86/X86InstrInfo.h - platform/external/llvm - Gitiles

 //===- 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 "X86RegisterInfo.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,

     // Bits 19 -> 23 are unused
     OpcodeShift   = 24,
     OpcodeMask    = 0xFF << OpcodeShift
   };
 }

 class X86InstrInfo : public TargetInstrInfo {
   X86TargetMachine &TM;
   const X86RegisterInfo RI;
 public:
   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 MRegisterInfo &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(MachineInstr *MI) const;
   bool isReallySideEffectFree(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) const;

   // Branch analysis.
   virtual bool isUnpredicatedTerminator(const MachineInstr* MI) const;
   virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
                              MachineBasicBlock *&FBB,
                              std::vector<MachineOperand> &Cond) const;
   virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const;
   virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
                                 MachineBasicBlock *FBB,
                                 const std::vector<MachineOperand> &Cond) const;
   virtual bool BlockHasNoFallThrough(MachineBasicBlock &MBB) const;
   virtual bool ReverseBranchCondition(std::vector<MachineOperand> &Cond) const;

   const TargetRegisterClass *getPointerRegClass() const;

   // getBaseOpcodeFor - This function returns the "base" X86 opcode for the
   // specified machine instruction.
   //
   unsigned char getBaseOpcodeFor(const TargetInstrDescriptor *TID) const {
     return TID->TSFlags >> X86II::OpcodeShift;
   }
   unsigned char getBaseOpcodeFor(MachineOpCode Opcode) const {
     return getBaseOpcodeFor(&get(Opcode));
   }
 };

 } // End llvm namespace

 #endif
	//===- 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 "X86RegisterInfo.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,

	// Bits 19 -> 23 are unused
	OpcodeShift = 24,
	OpcodeMask = 0xFF << OpcodeShift
	};
	}

	class X86InstrInfo : public TargetInstrInfo {
	X86TargetMachine &TM;
	const X86RegisterInfo RI;
	public:
	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 MRegisterInfo &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(MachineInstr *MI) const;
	bool isReallySideEffectFree(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) const;

	// Branch analysis.
	virtual bool isUnpredicatedTerminator(const MachineInstr* MI) const;
	virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
	MachineBasicBlock *&FBB,
	std::vector<MachineOperand> &Cond) const;
	virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const;
	virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
	MachineBasicBlock *FBB,
	const std::vector<MachineOperand> &Cond) const;
	virtual bool BlockHasNoFallThrough(MachineBasicBlock &MBB) const;
	virtual bool ReverseBranchCondition(std::vector<MachineOperand> &Cond) const;

	const TargetRegisterClass *getPointerRegClass() const;

	// getBaseOpcodeFor - This function returns the "base" X86 opcode for the
	// specified machine instruction.
	//
	unsigned char getBaseOpcodeFor(const TargetInstrDescriptor *TID) const {
	return TID->TSFlags >> X86II::OpcodeShift;
	}
	unsigned char getBaseOpcodeFor(MachineOpCode Opcode) const {
	return getBaseOpcodeFor(&get(Opcode));
	}
	};

	} // End llvm namespace

	#endif