| //===- X86RecognizableInstr.h - Disassembler instruction spec ----*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is part of the X86 Disassembler Emitter. |
| // It contains the interface of a single recognizable instruction. |
| // Documentation for the disassembler emitter in general can be found in |
| // X86DisasemblerEmitter.h. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef X86RECOGNIZABLEINSTR_H |
| #define X86RECOGNIZABLEINSTR_H |
| |
| #include "CodeGenTarget.h" |
| #include "X86DisassemblerTables.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/Support/DataTypes.h" |
| #include "llvm/TableGen/Record.h" |
| |
| namespace llvm { |
| |
| namespace X86Disassembler { |
| |
| /// RecognizableInstr - Encapsulates all information required to decode a single |
| /// instruction, as extracted from the LLVM instruction tables. Has methods |
| /// to interpret the information available in the LLVM tables, and to emit the |
| /// instruction into DisassemblerTables. |
| class RecognizableInstr { |
| private: |
| /// The opcode of the instruction, as used in an MCInst |
| InstrUID UID; |
| /// The record from the .td files corresponding to this instruction |
| const Record* Rec; |
| /// The prefix field from the record |
| uint8_t Prefix; |
| /// The opcode field from the record; this is the opcode used in the Intel |
| /// encoding and therefore distinct from the UID |
| uint8_t Opcode; |
| /// The form field from the record |
| uint8_t Form; |
| /// The segment override field from the record |
| uint8_t SegOvr; |
| /// The hasOpSizePrefix field from the record |
| bool HasOpSizePrefix; |
| /// The hasAdSizePrefix field from the record |
| bool HasAdSizePrefix; |
| /// The hasREX_WPrefix field from the record |
| bool HasREX_WPrefix; |
| /// The hasVEXPrefix field from the record |
| bool HasVEXPrefix; |
| /// The hasVEX_4VPrefix field from the record |
| bool HasVEX_4VPrefix; |
| /// The hasVEX_4VOp3Prefix field from the record |
| bool HasVEX_4VOp3Prefix; |
| /// The hasVEX_WPrefix field from the record |
| bool HasVEX_WPrefix; |
| /// Inferred from the operands; indicates whether the L bit in the VEX prefix is set |
| bool HasVEX_LPrefix; |
| /// The hasMemOp4Prefix field from the record |
| bool HasMemOp4Prefix; |
| /// The ignoreVEX_L field from the record |
| bool IgnoresVEX_L; |
| /// The hasLockPrefix field from the record |
| bool HasLockPrefix; |
| /// The isCodeGenOnly filed from the record |
| bool IsCodeGenOnly; |
| // Whether the instruction has the predicate "In64BitMode" |
| bool Is64Bit; |
| // Whether the instruction has the predicate "In32BitMode" |
| bool Is32Bit; |
| |
| /// The instruction name as listed in the tables |
| std::string Name; |
| /// The AT&T AsmString for the instruction |
| std::string AsmString; |
| |
| /// Indicates whether the instruction is SSE |
| bool IsSSE; |
| /// Indicates whether the instruction has FR operands - MOVs with FR operands |
| /// are typically ignored |
| bool HasFROperands; |
| /// Indicates whether the instruction should be emitted into the decode |
| /// tables; regardless, it will be emitted into the instruction info table |
| bool ShouldBeEmitted; |
| |
| /// The operands of the instruction, as listed in the CodeGenInstruction. |
| /// They are not one-to-one with operands listed in the MCInst; for example, |
| /// memory operands expand to 5 operands in the MCInst |
| const std::vector<CGIOperandList::OperandInfo>* Operands; |
| |
| /// The description of the instruction that is emitted into the instruction |
| /// info table |
| InstructionSpecifier* Spec; |
| |
| /// insnContext - Returns the primary context in which the instruction is |
| /// valid. |
| /// |
| /// @return - The context in which the instruction is valid. |
| InstructionContext insnContext() const; |
| |
| enum filter_ret { |
| FILTER_STRONG, // instruction has no place in the instruction tables |
| FILTER_WEAK, // instruction may conflict, and should be eliminated if |
| // it does |
| FILTER_NORMAL // instruction should have high priority and generate an |
| // error if it conflcits with any other FILTER_NORMAL |
| // instruction |
| }; |
| |
| /// filter - Determines whether the instruction should be decodable. Some |
| /// instructions are pure intrinsics and use unencodable operands; many |
| /// synthetic instructions are duplicates of other instructions; other |
| /// instructions only differ in the logical way in which they are used, and |
| /// have the same decoding. Because these would cause decode conflicts, |
| /// they must be filtered out. |
| /// |
| /// @return - The degree of filtering to be applied (see filter_ret). |
| filter_ret filter() const; |
| |
| /// hasFROperands - Returns true if any operand is a FR operand. |
| bool hasFROperands() const; |
| |
| /// typeFromString - Translates an operand type from the string provided in |
| /// the LLVM tables to an OperandType for use in the operand specifier. |
| /// |
| /// @param s - The string, as extracted by calling Rec->getName() |
| /// on a CodeGenInstruction::OperandInfo. |
| /// @param isSSE - Indicates whether the instruction is an SSE |
| /// instruction. For SSE instructions, immediates are |
| /// fixed-size rather than being affected by the |
| /// mandatory OpSize prefix. |
| /// @param hasREX_WPrefix - Indicates whether the instruction has a REX.W |
| /// prefix. If it does, 32-bit register operands stay |
| /// 32-bit regardless of the operand size. |
| /// @param hasOpSizePrefix Indicates whether the instruction has an OpSize |
| /// prefix. If it does not, then 16-bit register |
| /// operands stay 16-bit. |
| /// @return - The operand's type. |
| static OperandType typeFromString(const std::string& s, |
| bool isSSE, |
| bool hasREX_WPrefix, |
| bool hasOpSizePrefix); |
| |
| /// immediateEncodingFromString - Translates an immediate encoding from the |
| /// string provided in the LLVM tables to an OperandEncoding for use in |
| /// the operand specifier. |
| /// |
| /// @param s - See typeFromString(). |
| /// @param hasOpSizePrefix - Indicates whether the instruction has an OpSize |
| /// prefix. If it does not, then 16-bit immediate |
| /// operands stay 16-bit. |
| /// @return - The operand's encoding. |
| static OperandEncoding immediateEncodingFromString(const std::string &s, |
| bool hasOpSizePrefix); |
| |
| /// rmRegisterEncodingFromString - Like immediateEncodingFromString, but |
| /// handles operands that are in the REG field of the ModR/M byte. |
| static OperandEncoding rmRegisterEncodingFromString(const std::string &s, |
| bool hasOpSizePrefix); |
| |
| /// rmRegisterEncodingFromString - Like immediateEncodingFromString, but |
| /// handles operands that are in the REG field of the ModR/M byte. |
| static OperandEncoding roRegisterEncodingFromString(const std::string &s, |
| bool hasOpSizePrefix); |
| static OperandEncoding memoryEncodingFromString(const std::string &s, |
| bool hasOpSizePrefix); |
| static OperandEncoding relocationEncodingFromString(const std::string &s, |
| bool hasOpSizePrefix); |
| static OperandEncoding opcodeModifierEncodingFromString(const std::string &s, |
| bool hasOpSizePrefix); |
| static OperandEncoding vvvvRegisterEncodingFromString(const std::string &s, |
| bool HasOpSizePrefix); |
| |
| /// handleOperand - Converts a single operand from the LLVM table format to |
| /// the emitted table format, handling any duplicate operands it encounters |
| /// and then one non-duplicate. |
| /// |
| /// @param optional - Determines whether to assert that the |
| /// operand exists. |
| /// @param operandIndex - The index into the generated operand table. |
| /// Incremented by this function one or more |
| /// times to reflect possible duplicate |
| /// operands). |
| /// @param physicalOperandIndex - The index of the current operand into the |
| /// set of non-duplicate ('physical') operands. |
| /// Incremented by this function once. |
| /// @param numPhysicalOperands - The number of non-duplicate operands in the |
| /// instructions. |
| /// @param operandMapping - The operand mapping, which has an entry for |
| /// each operand that indicates whether it is a |
| /// duplicate, and of what. |
| void handleOperand(bool optional, |
| unsigned &operandIndex, |
| unsigned &physicalOperandIndex, |
| unsigned &numPhysicalOperands, |
| const unsigned *operandMapping, |
| OperandEncoding (*encodingFromString) |
| (const std::string&, |
| bool hasOpSizePrefix)); |
| |
| /// shouldBeEmitted - Returns the shouldBeEmitted field. Although filter() |
| /// filters out many instructions, at various points in decoding we |
| /// determine that the instruction should not actually be decodable. In |
| /// particular, MMX MOV instructions aren't emitted, but they're only |
| /// identified during operand parsing. |
| /// |
| /// @return - true if at this point we believe the instruction should be |
| /// emitted; false if not. This will return false if filter() returns false |
| /// once emitInstructionSpecifier() has been called. |
| bool shouldBeEmitted() const { |
| return ShouldBeEmitted; |
| } |
| |
| /// emitInstructionSpecifier - Loads the instruction specifier for the current |
| /// instruction into a DisassemblerTables. |
| /// |
| /// \param tables The DisassemblerTables to populate with the specifier for |
| /// the current instruction. |
| void emitInstructionSpecifier(DisassemblerTables &tables); |
| |
| /// emitDecodePath - Populates the proper fields in the decode tables |
| /// corresponding to the decode paths for this instruction. |
| /// |
| /// \param tables The DisassemblerTables to populate with the decode |
| /// decode information for the current instruction. |
| void emitDecodePath(DisassemblerTables &tables) const; |
| |
| /// Constructor - Initializes a RecognizableInstr with the appropriate fields |
| /// from a CodeGenInstruction. |
| /// |
| /// \param tables The DisassemblerTables that the specifier will be added to. |
| /// \param insn The CodeGenInstruction to extract information from. |
| /// \param uid The unique ID of the current instruction. |
| RecognizableInstr(DisassemblerTables &tables, |
| const CodeGenInstruction &insn, |
| InstrUID uid); |
| public: |
| /// processInstr - Accepts a CodeGenInstruction and loads decode information |
| /// for it into a DisassemblerTables if appropriate. |
| /// |
| /// \param tables The DiassemblerTables to be populated with decode |
| /// information. |
| /// \param insn The CodeGenInstruction to be used as a source for this |
| /// information. |
| /// \param uid The unique ID of the instruction. |
| static void processInstr(DisassemblerTables &tables, |
| const CodeGenInstruction &insn, |
| InstrUID uid); |
| }; |
| |
| } // namespace X86Disassembler |
| |
| } // namespace llvm |
| |
| #endif |
