freebsd-dev/contrib/llvm/utils/TableGen/X86RecognizableInstr.h
Ed Schouten ffd1746d03 Upgrade our Clang in base to r108428.
This commit merges the latest LLVM sources from the vendor space. It
also updates the build glue to match the new sources. Clang's version
number is changed to match LLVM's, which means /usr/include/clang/2.0
has been renamed to /usr/include/clang/2.8.

Obtained from:	projects/clangbsd
2010-07-20 17:16:57 +00:00

240 lines
11 KiB
C++

//===- 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 "X86DisassemblerTables.h"
#include "CodeGenTarget.h"
#include "Record.h"
#include "llvm/System/DataTypes.h"
#include "llvm/ADT/SmallVector.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 hasREX_WPrefix field from the record
bool HasREX_WPrefix;
/// The hasVEX_4VPrefix field from the record
bool HasVEX_4VPrefix;
/// The hasLockPrefix field from the record
bool HasLockPrefix;
/// The isCodeGenOnly filed from the record
bool IsCodeGenOnly;
/// 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<CodeGenInstruction::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;
/// 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);
/// 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,
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.
///
/// @arg 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.
///
/// @arg 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.
///
/// @arg tables - The DisassemblerTables that the specifier will be added to.
/// @arg insn - The CodeGenInstruction to extract information from.
/// @arg 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.
///
/// @arg tables - The DiassemblerTables to be populated with decode
/// information.
/// @arg insn - The CodeGenInstruction to be used as a source for this
/// information.
/// @uid - The unique ID of the instruction.
static void processInstr(DisassemblerTables &tables,
const CodeGenInstruction &insn,
InstrUID uid);
};
} // namespace X86Disassembler
} // namespace llvm
#endif