X86InstrInfo.h revision 915e5e56d7cc8e140d33202eed6244ed0356ed1f
1//===- X86InstrInfo.h - X86 Instruction Information ------------*- C++ -*- ===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file was developed by the LLVM research group and is distributed under 6// the University of Illinois Open Source License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file contains the X86 implementation of the TargetInstrInfo class. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef X86INSTRUCTIONINFO_H 15#define X86INSTRUCTIONINFO_H 16 17#include "llvm/Target/TargetInstrInfo.h" 18#include "X86RegisterInfo.h" 19 20namespace llvm { 21 22/// X86II - This namespace holds all of the target specific flags that 23/// instruction info tracks. 24/// 25namespace X86II { 26 enum { 27 //===------------------------------------------------------------------===// 28 // Instruction types. These are the standard/most common forms for X86 29 // instructions. 30 // 31 32 // PseudoFrm - This represents an instruction that is a pseudo instruction 33 // or one that has not been implemented yet. It is illegal to code generate 34 // it, but tolerated for intermediate implementation stages. 35 Pseudo = 0, 36 37 /// Raw - This form is for instructions that don't have any operands, so 38 /// they are just a fixed opcode value, like 'leave'. 39 RawFrm = 1, 40 41 /// AddRegFrm - This form is used for instructions like 'push r32' that have 42 /// their one register operand added to their opcode. 43 AddRegFrm = 2, 44 45 /// MRMDestReg - This form is used for instructions that use the Mod/RM byte 46 /// to specify a destination, which in this case is a register. 47 /// 48 MRMDestReg = 3, 49 50 /// MRMDestMem - This form is used for instructions that use the Mod/RM byte 51 /// to specify a destination, which in this case is memory. 52 /// 53 MRMDestMem = 4, 54 55 /// MRMSrcReg - This form is used for instructions that use the Mod/RM byte 56 /// to specify a source, which in this case is a register. 57 /// 58 MRMSrcReg = 5, 59 60 /// MRMSrcMem - This form is used for instructions that use the Mod/RM byte 61 /// to specify a source, which in this case is memory. 62 /// 63 MRMSrcMem = 6, 64 65 /// MRMS[0-7][rm] - These forms are used to represent instructions that use 66 /// a Mod/RM byte, and use the middle field to hold extended opcode 67 /// information. In the intel manual these are represented as /0, /1, ... 68 /// 69 70 // First, instructions that operate on a register r/m operand... 71 MRMS0r = 16, MRMS1r = 17, MRMS2r = 18, MRMS3r = 19, // Format /0 /1 /2 /3 72 MRMS4r = 20, MRMS5r = 21, MRMS6r = 22, MRMS7r = 23, // Format /4 /5 /6 /7 73 74 // Next, instructions that operate on a memory r/m operand... 75 MRMS0m = 24, MRMS1m = 25, MRMS2m = 26, MRMS3m = 27, // Format /0 /1 /2 /3 76 MRMS4m = 28, MRMS5m = 29, MRMS6m = 30, MRMS7m = 31, // Format /4 /5 /6 /7 77 78 FormMask = 31, 79 80 //===------------------------------------------------------------------===// 81 // Actual flags... 82 83 // OpSize - Set if this instruction requires an operand size prefix (0x66), 84 // which most often indicates that the instruction operates on 16 bit data 85 // instead of 32 bit data. 86 OpSize = 1 << 5, 87 88 // Op0Mask - There are several prefix bytes that are used to form two byte 89 // opcodes. These are currently 0x0F, 0xF3, and 0xD8-0xDF. This mask is 90 // used to obtain the setting of this field. If no bits in this field is 91 // set, there is no prefix byte for obtaining a multibyte opcode. 92 // 93 Op0Shift = 6, 94 Op0Mask = 0xF << Op0Shift, 95 96 // TB - TwoByte - Set if this instruction has a two byte opcode, which 97 // starts with a 0x0F byte before the real opcode. 98 TB = 1 << Op0Shift, 99 100 // REP - The 0xF3 prefix byte indicating repetition of the following 101 // instruction. 102 REP = 2 << Op0Shift, 103 104 // D8-DF - These escape opcodes are used by the floating point unit. These 105 // values must remain sequential. 106 D8 = 3 << Op0Shift, D9 = 4 << Op0Shift, 107 DA = 5 << Op0Shift, DB = 6 << Op0Shift, 108 DC = 7 << Op0Shift, DD = 8 << Op0Shift, 109 DE = 9 << Op0Shift, DF = 10 << Op0Shift, 110 111 //===------------------------------------------------------------------===// 112 // This three-bit field describes the size of a memory operand. Zero is 113 // unused so that we can tell if we forgot to set a value. 114 ArgShift = 10, 115 ArgMask = 7 << ArgShift, 116 Arg8 = 1 << ArgShift, 117 Arg16 = 2 << ArgShift, 118 Arg32 = 3 << ArgShift, 119 Arg64 = 4 << ArgShift, // 64 bit int argument for FILD64 120 ArgF32 = 5 << ArgShift, 121 ArgF64 = 6 << ArgShift, 122 ArgF80 = 7 << ArgShift, 123 124 //===------------------------------------------------------------------===// 125 // FP Instruction Classification... Zero is non-fp instruction. 126 127 // FPTypeMask - Mask for all of the FP types... 128 FPTypeShift = 13, 129 FPTypeMask = 7 << FPTypeShift, 130 131 // NotFP - The default, set for instructions that do not use FP registers. 132 NotFP = 0 << FPTypeShift, 133 134 // ZeroArgFP - 0 arg FP instruction which implicitly pushes ST(0), f.e. fld0 135 ZeroArgFP = 1 << FPTypeShift, 136 137 // OneArgFP - 1 arg FP instructions which implicitly read ST(0), such as fst 138 OneArgFP = 2 << FPTypeShift, 139 140 // OneArgFPRW - 1 arg FP instruction which implicitly read ST(0) and write a 141 // result back to ST(0). For example, fcos, fsqrt, etc. 142 // 143 OneArgFPRW = 3 << FPTypeShift, 144 145 // TwoArgFP - 2 arg FP instructions which implicitly read ST(0), and an 146 // explicit argument, storing the result to either ST(0) or the implicit 147 // argument. For example: fadd, fsub, fmul, etc... 148 TwoArgFP = 4 << FPTypeShift, 149 150 // SpecialFP - Special instruction forms. Dispatch by opcode explicitly. 151 SpecialFP = 5 << FPTypeShift, 152 153 // PrintImplUses - Print out implicit uses in the assembly output. 154 PrintImplUses = 1 << 16, 155 156 OpcodeShift = 17, 157 OpcodeMask = 0xFF << OpcodeShift, 158 // Bits 25 -> 31 are unused 159 }; 160} 161 162class X86InstrInfo : public TargetInstrInfo { 163 const X86RegisterInfo RI; 164public: 165 X86InstrInfo(); 166 167 /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As 168 /// such, whenever a client has an instance of instruction info, it should 169 /// always be able to get register info as well (through this method). 170 /// 171 virtual const MRegisterInfo &getRegisterInfo() const { return RI; } 172 173 /// createNOPinstr - returns the target's implementation of NOP, which is 174 /// usually a pseudo-instruction, implemented by a degenerate version of 175 /// another instruction, e.g. X86: `xchg ax, ax'; SparcV9: `sethi r0, r0, r0' 176 /// 177 MachineInstr* createNOPinstr() const; 178 179 // 180 // Return true if the instruction is a register to register move and 181 // leave the source and dest operands in the passed parameters. 182 // 183 virtual bool isMoveInstr(const MachineInstr& MI, 184 unsigned& sourceReg, 185 unsigned& destReg) const; 186 187 /// isNOPinstr - not having a special NOP opcode, we need to know if a given 188 /// instruction is interpreted as an `official' NOP instr, i.e., there may be 189 /// more than one way to `do nothing' but only one canonical way to slack off. 190 /// 191 bool isNOPinstr(const MachineInstr &MI) const; 192 193 // getBaseOpcodeFor - This function returns the "base" X86 opcode for the 194 // specified opcode number. 195 // 196 unsigned char getBaseOpcodeFor(unsigned Opcode) const { 197 return get(Opcode).TSFlags >> X86II::OpcodeShift; 198 } 199}; 200 201} // End llvm namespace 202 203#endif 204