//===--- TargetInfo.h - Expose information about the target -----*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

///

/// \file

/// Defines the clang::TargetInfo interface.

///

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_BASIC_TARGETINFO_H

#define LLVM_CLANG_BASIC_TARGETINFO_H

#include "clang/Basic/AddressSpaces.h"

#include "clang/Basic/LLVM.h"

#include "clang/Basic/CodeGenOptions.h"

#include "clang/Basic/Specifiers.h"

#include "clang/Basic/TargetCXXABI.h"

#include "clang/Basic/TargetOptions.h"

#include "llvm/ADT/APFloat.h"

#include "llvm/ADT/APInt.h"

#include "llvm/ADT/ArrayRef.h"

#include "llvm/ADT/IntrusiveRefCntPtr.h"

#include "llvm/ADT/Optional.h"

#include "llvm/ADT/SmallSet.h"

#include "llvm/ADT/StringMap.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/ADT/Triple.h"

#include "llvm/Support/DataTypes.h"

#include "llvm/Support/VersionTuple.h"

#include <cassert>

#include <string>

#include <vector>

namespace llvm {

struct fltSemantics;

class DataLayout;

}

namespace clang {

class DiagnosticsEngine;

class LangOptions;

class CodeGenOptions;

class MacroBuilder;

class QualType;

class SourceLocation;

class SourceManager;

namespace Builtin { struct Info; }

/// Fields controlling how types are laid out in memory; these may need to

/// be copied for targets like AMDGPU that base their ABIs on an auxiliary

/// CPU target.

struct TransferrableTargetInfo {

  unsigned char PointerWidth, PointerAlign;

  unsigned char BoolWidth, BoolAlign;

  unsigned char IntWidth, IntAlign;

  unsigned char HalfWidth, HalfAlign;

  unsigned char FloatWidth, FloatAlign;

  unsigned char DoubleWidth, DoubleAlign;

  unsigned char LongDoubleWidth, LongDoubleAlign, Float128Align;

  unsigned char LargeArrayMinWidth, LargeArrayAlign;

  unsigned char LongWidth, LongAlign;

  unsigned char LongLongWidth, LongLongAlign;

  // Fixed point bit widths

  unsigned char ShortAccumWidth, ShortAccumAlign;

  unsigned char AccumWidth, AccumAlign;

  unsigned char LongAccumWidth, LongAccumAlign;

  unsigned char ShortFractWidth, ShortFractAlign;

  unsigned char FractWidth, FractAlign;

  unsigned char LongFractWidth, LongFractAlign;

  // If true, unsigned fixed point types have the same number of fractional bits

  // as their signed counterparts, forcing the unsigned types to have one extra

  // bit of padding. Otherwise, unsigned fixed point types have

  // one more fractional bit than its corresponding signed type. This is false

  // by default.

  bool PaddingOnUnsignedFixedPoint;

  // Fixed point integral and fractional bit sizes

  // Saturated types share the same integral/fractional bits as their

  // corresponding unsaturated types.

  // For simplicity, the fractional bits in a _Fract type will be one less the

  // width of that _Fract type. This leaves all signed _Fract types having no

  // padding and unsigned _Fract types will only have 1 bit of padding after the

  // sign if PaddingOnUnsignedFixedPoint is set.

  unsigned char ShortAccumScale;

  unsigned char AccumScale;

  unsigned char LongAccumScale;

  unsigned char SuitableAlign;

  unsigned char DefaultAlignForAttributeAligned;

  unsigned char MinGlobalAlign;

  unsigned short NewAlign;

  unsigned short MaxVectorAlign;

  unsigned short MaxTLSAlign;

  const llvm::fltSemantics *HalfFormat, *FloatFormat, *DoubleFormat,

    *LongDoubleFormat, *Float128Format;

  ///===---- Target Data Type Query Methods -------------------------------===//

  enum IntType {

    NoInt = 0,

    SignedChar,

    UnsignedChar,

    SignedShort,

    UnsignedShort,

    SignedInt,

    UnsignedInt,

    SignedLong,

    UnsignedLong,

    SignedLongLong,

    UnsignedLongLong

  };

  enum RealType {

    NoFloat = 255,

    Float = 0,

    Double,

    LongDouble,

    Float128

  };

protected:

  IntType SizeType, IntMaxType, PtrDiffType, IntPtrType, WCharType,

          WIntType, Char16Type, Char32Type, Int64Type, SigAtomicType,

          ProcessIDType;

  /// Whether Objective-C's built-in boolean type should be signed char.

  ///

  /// Otherwise, when this flag is not set, the normal built-in boolean type is

  /// used.

  unsigned UseSignedCharForObjCBool : 1;

  /// Control whether the alignment of bit-field types is respected when laying

  /// out structures. If true, then the alignment of the bit-field type will be

  /// used to (a) impact the alignment of the containing structure, and (b)

  /// ensure that the individual bit-field will not straddle an alignment

  /// boundary.

  unsigned UseBitFieldTypeAlignment : 1;

  /// Whether zero length bitfields (e.g., int : 0;) force alignment of

  /// the next bitfield.

  ///

  /// If the alignment of the zero length bitfield is greater than the member

  /// that follows it, `bar', `bar' will be aligned as the type of the

  /// zero-length bitfield.

  unsigned UseZeroLengthBitfieldAlignment : 1;

  ///  Whether explicit bit field alignment attributes are honored.

  unsigned UseExplicitBitFieldAlignment : 1;

  /// If non-zero, specifies a fixed alignment value for bitfields that follow

  /// zero length bitfield, regardless of the zero length bitfield type.

  unsigned ZeroLengthBitfieldBoundary;

};

/// Exposes information about the current target.

///

class TargetInfo : public virtual TransferrableTargetInfo,

                   public RefCountedBase<TargetInfo> {

  std::shared_ptr<TargetOptions> TargetOpts;

  llvm::Triple Triple;

protected:

  // Target values set by the ctor of the actual target implementation.  Default

  // values are specified by the TargetInfo constructor.

  bool BigEndian;

  bool TLSSupported;

  bool VLASupported;

  bool NoAsmVariants;  // True if {|} are normal characters.

  bool HasLegalHalfType; // True if the backend supports operations on the half

                         // LLVM IR type.

  bool HasFloat128;

  bool HasFloat16;

  unsigned char MaxAtomicPromoteWidth, MaxAtomicInlineWidth;

  unsigned short SimdDefaultAlign;

  std::unique_ptr<llvm::DataLayout> DataLayout;

  const char *MCountName;

  unsigned char RegParmMax, SSERegParmMax;

  TargetCXXABI TheCXXABI;

  const LangASMap *AddrSpaceMap;

  mutable StringRef PlatformName;

  mutable VersionTuple PlatformMinVersion;

  unsigned HasAlignMac68kSupport : 1;

  unsigned RealTypeUsesObjCFPRet : 3;

  unsigned ComplexLongDoubleUsesFP2Ret : 1;

  unsigned HasBuiltinMSVaList : 1;

  unsigned IsRenderScriptTarget : 1;

  unsigned HasAArch64SVETypes : 1;

  // TargetInfo Constructor.  Default initializes all fields.

  TargetInfo(const llvm::Triple &T);

  void resetDataLayout(StringRef DL);

public:

  /// Construct a target for the given options.

  ///

  /// \param Opts - The options to use to initialize the target. The target may

  /// modify the options to canonicalize the target feature information to match

  /// what the backend expects.

  static TargetInfo *

  CreateTargetInfo(DiagnosticsEngine &Diags,

                   const std::shared_ptr<TargetOptions> &Opts);

  virtual ~TargetInfo();

  /// Retrieve the target options.

  TargetOptions &getTargetOpts() const {

    assert(TargetOpts && "Missing target options");

    return *TargetOpts;

  }

  /// The different kinds of __builtin_va_list types defined by

  /// the target implementation.

  enum BuiltinVaListKind {

    /// typedef char* __builtin_va_list;

    CharPtrBuiltinVaList = 0,

    /// typedef void* __builtin_va_list;

    VoidPtrBuiltinVaList,

    /// __builtin_va_list as defined by the AArch64 ABI

    /// http://infocenter.arm.com/help/topic/com.arm.doc.ihi0055a/IHI0055A_aapcs64.pdf

    AArch64ABIBuiltinVaList,

    /// __builtin_va_list as defined by the PNaCl ABI:

    /// http://www.chromium.org/nativeclient/pnacl/bitcode-abi#TOC-Machine-Types

    PNaClABIBuiltinVaList,

    /// __builtin_va_list as defined by the Power ABI:

    /// https://www.power.org

    ///        /resources/downloads/Power-Arch-32-bit-ABI-supp-1.0-Embedded.pdf

    PowerABIBuiltinVaList,

    /// __builtin_va_list as defined by the x86-64 ABI:

    /// http://refspecs.linuxbase.org/elf/x86_64-abi-0.21.pdf

    X86_64ABIBuiltinVaList,

    /// __builtin_va_list as defined by ARM AAPCS ABI

    /// http://infocenter.arm.com

    //        /help/topic/com.arm.doc.ihi0042d/IHI0042D_aapcs.pdf

    AAPCSABIBuiltinVaList,

    // typedef struct __va_list_tag

    //   {

    //     long __gpr;

    //     long __fpr;

    //     void *__overflow_arg_area;

    //     void *__reg_save_area;

    //   } va_list[1];

    SystemZBuiltinVaList

  };

protected:

  /// Specify if mangling based on address space map should be used or

  /// not for language specific address spaces

  bool UseAddrSpaceMapMangling;

public:

  IntType getSizeType() const { return SizeType; }

  IntType getSignedSizeType() const {

    switch (SizeType) {

    case UnsignedShort:

      return SignedShort;

    case UnsignedInt:

      return SignedInt;

    case UnsignedLong:

      return SignedLong;

    case UnsignedLongLong:

      return SignedLongLong;

    default:

      llvm_unreachable("Invalid SizeType");

    }

  }

  IntType getIntMaxType() const { return IntMaxType; }

  IntType getUIntMaxType() const {

    return getCorrespondingUnsignedType(IntMaxType);

  }

  IntType getPtrDiffType(unsigned AddrSpace) const {

    return AddrSpace == 0 ? PtrDiffType : 
getPtrDiffTypeV(AddrSpace)0
;

  }

  IntType getUnsignedPtrDiffType(unsigned AddrSpace) const {

    return getCorrespondingUnsignedType(getPtrDiffType(AddrSpace));

  }

  IntType getIntPtrType() const { return IntPtrType; }

  IntType getUIntPtrType() const {

    return getCorrespondingUnsignedType(IntPtrType);

  }

  IntType getWCharType() const { return WCharType; }

  IntType getWIntType() const { return WIntType; }

  IntType getChar16Type() const { return Char16Type; }

  IntType getChar32Type() const { return Char32Type; }

  IntType getInt64Type() const { return Int64Type; }

  IntType getUInt64Type() const {

    return getCorrespondingUnsignedType(Int64Type);

  }

  IntType getSigAtomicType() const { return SigAtomicType; }

  IntType getProcessIDType() const { return ProcessIDType; }

  static IntType getCorrespondingUnsignedType(IntType T) {

    switch (T) {

    case SignedChar:

      return UnsignedChar;

    case SignedShort:

      return UnsignedShort;

    case SignedInt:

      return UnsignedInt;

    case SignedLong:

      return UnsignedLong;

    case SignedLongLong:

      return UnsignedLongLong;

    default:

      llvm_unreachable("Unexpected signed integer type");

    }

  }

  /// In the event this target uses the same number of fractional bits for its

  /// unsigned types as it does with its signed counterparts, there will be

  /// exactly one bit of padding.

  /// Return true if unsigned fixed point types have padding for this target.

  bool doUnsignedFixedPointTypesHavePadding() const {

    return PaddingOnUnsignedFixedPoint;

  }

  /// Return the width (in bits) of the specified integer type enum.

  ///

  /// For example, SignedInt -> getIntWidth().

  unsigned getTypeWidth(IntType T) const;

  /// Return integer type with specified width.

  virtual IntType getIntTypeByWidth(unsigned BitWidth, bool IsSigned) const;

  /// Return the smallest integer type with at least the specified width.

  virtual IntType getLeastIntTypeByWidth(unsigned BitWidth,

                                         bool IsSigned) const;

  /// Return floating point type with specified width.

  RealType getRealTypeByWidth(unsigned BitWidth) const;

  /// Return the alignment (in bits) of the specified integer type enum.

  ///

  /// For example, SignedInt -> getIntAlign().

  unsigned getTypeAlign(IntType T) const;

  /// Returns true if the type is signed; false otherwise.

  static bool isTypeSigned(IntType T);

  /// Return the width of pointers on this target, for the

  /// specified address space.

  uint64_t getPointerWidth(unsigned AddrSpace) const {

    return AddrSpace == 0 ? 
PointerWidth1.44M
 : 
getPointerWidthV(AddrSpace)978
;

  }

  uint64_t getPointerAlign(unsigned AddrSpace) const {

    return AddrSpace == 0 ? 
PointerAlign579k
 : 
getPointerAlignV(AddrSpace)885
;

  }

  /// Return the maximum width of pointers on this target.

  virtual uint64_t getMaxPointerWidth() const {

    return PointerWidth;

  }

  /// Get integer value for null pointer.

  /// \param AddrSpace address space of pointee in source language.

  virtual uint64_t getNullPointerValue(LangAS AddrSpace) const { return 0; }

  /// Return the size of '_Bool' and C++ 'bool' for this target, in bits.

  unsigned getBoolWidth() const { return BoolWidth; }

  /// Return the alignment of '_Bool' and C++ 'bool' for this target.

  unsigned getBoolAlign() const { return BoolAlign; }

  unsigned getCharWidth() const { return 8; } // FIXME

  unsigned getCharAlign() const { return 8; } // FIXME

  /// Return the size of 'signed short' and 'unsigned short' for this

  /// target, in bits.

  unsigned getShortWidth() const { return 16; } // FIXME

  /// Return the alignment of 'signed short' and 'unsigned short' for

  /// this target.

  unsigned getShortAlign() const { return 16; } // FIXME

  /// getIntWidth/Align - Return the size of 'signed int' and 'unsigned int' for

  /// this target, in bits.

  unsigned getIntWidth() const { return IntWidth; }

  unsigned getIntAlign() const { return IntAlign; }

  /// getLongWidth/Align - Return the size of 'signed long' and 'unsigned long'

  /// for this target, in bits.

  unsigned getLongWidth() const { return LongWidth; }

  unsigned getLongAlign() const { return LongAlign; }

  /// getLongLongWidth/Align - Return the size of 'signed long long' and

  /// 'unsigned long long' for this target, in bits.

  unsigned getLongLongWidth() const { return LongLongWidth; }

  unsigned getLongLongAlign() const { return LongLongAlign; }

  /// getShortAccumWidth/Align - Return the size of 'signed short _Accum' and

  /// 'unsigned short _Accum' for this target, in bits.

  unsigned getShortAccumWidth() const { return ShortAccumWidth; }

  unsigned getShortAccumAlign() const { return ShortAccumAlign; }

  /// getAccumWidth/Align - Return the size of 'signed _Accum' and

  /// 'unsigned _Accum' for this target, in bits.

  unsigned getAccumWidth() const { return AccumWidth; }

  unsigned getAccumAlign() const { return AccumAlign; }

  /// getLongAccumWidth/Align - Return the size of 'signed long _Accum' and

  /// 'unsigned long _Accum' for this target, in bits.

  unsigned getLongAccumWidth() const { return LongAccumWidth; }

  unsigned getLongAccumAlign() const { return LongAccumAlign; }

  /// getShortFractWidth/Align - Return the size of 'signed short _Fract' and

  /// 'unsigned short _Fract' for this target, in bits.

  unsigned getShortFractWidth() const { return ShortFractWidth; }

  unsigned getShortFractAlign() const { return ShortFractAlign; }

  /// getFractWidth/Align - Return the size of 'signed _Fract' and

  /// 'unsigned _Fract' for this target, in bits.

  unsigned getFractWidth() const { return FractWidth; }

  unsigned getFractAlign() const { return FractAlign; }

  /// getLongFractWidth/Align - Return the size of 'signed long _Fract' and

  /// 'unsigned long _Fract' for this target, in bits.

  unsigned getLongFractWidth() const { return LongFractWidth; }

  unsigned getLongFractAlign() const { return LongFractAlign; }

  /// getShortAccumScale/IBits - Return the number of fractional/integral bits

  /// in a 'signed short _Accum' type.

  unsigned getShortAccumScale() const { return ShortAccumScale; }

  unsigned getShortAccumIBits() const {

    return ShortAccumWidth - ShortAccumScale - 1;

  }

  /// getAccumScale/IBits - Return the number of fractional/integral bits

  /// in a 'signed _Accum' type.

  unsigned getAccumScale() const { return AccumScale; }

  unsigned getAccumIBits() const { return AccumWidth - AccumScale - 1; }

  /// getLongAccumScale/IBits - Return the number of fractional/integral bits

  /// in a 'signed long _Accum' type.

  unsigned getLongAccumScale() const { return LongAccumScale; }

  unsigned getLongAccumIBits() const {

    return LongAccumWidth - LongAccumScale - 1;

  }

  /// getUnsignedShortAccumScale/IBits - Return the number of

  /// fractional/integral bits in a 'unsigned short _Accum' type.

  unsigned getUnsignedShortAccumScale() const {

    return PaddingOnUnsignedFixedPoint ? 
ShortAccumScale422
 : 
ShortAccumScale + 1919k
;

  }

  unsigned getUnsignedShortAccumIBits() const {

    return PaddingOnUnsignedFixedPoint

               ? 
getShortAccumIBits()42

               : 
ShortAccumWidth - getUnsignedShortAccumScale()551k
;

  }

  /// getUnsignedAccumScale/IBits - Return the number of fractional/integral

  /// bits in a 'unsigned _Accum' type.

  unsigned getUnsignedAccumScale() const {

    return PaddingOnUnsignedFixedPoint ? 
AccumScale115
 : 
AccumScale + 11.28M
;

  }

  unsigned getUnsignedAccumIBits() const {

    return PaddingOnUnsignedFixedPoint ? 
getAccumIBits()56

                                       : 
AccumWidth - getUnsignedAccumScale()735k
;

  }

  /// getUnsignedLongAccumScale/IBits - Return the number of fractional/integral

  /// bits in a 'unsigned long _Accum' type.

  unsigned getUnsignedLongAccumScale() const {

    return PaddingOnUnsignedFixedPoint ? 
LongAccumScale34
 : 
LongAccumScale + 1919k
;

  }

  unsigned getUnsignedLongAccumIBits() const {

    return PaddingOnUnsignedFixedPoint

               ? 
getLongAccumIBits()42

               : 
LongAccumWidth - getUnsignedLongAccumScale()551k
;

  }

  /// getShortFractScale - Return the number of fractional bits

  /// in a 'signed short _Fract' type.

  unsigned getShortFractScale() const { return ShortFractWidth - 1; }

  /// getFractScale - Return the number of fractional bits

  /// in a 'signed _Fract' type.

  unsigned getFractScale() const { return FractWidth - 1; }

  /// getLongFractScale - Return the number of fractional bits

  /// in a 'signed long _Fract' type.

  unsigned getLongFractScale() const { return LongFractWidth - 1; }

  /// getUnsignedShortFractScale - Return the number of fractional bits

  /// in a 'unsigned short _Fract' type.

  unsigned getUnsignedShortFractScale() const {

    return PaddingOnUnsignedFixedPoint ? 
getShortFractScale()51

                                       : 
getShortFractScale() + 1735k
;

  }

  /// getUnsignedFractScale - Return the number of fractional bits

  /// in a 'unsigned _Fract' type.

  unsigned getUnsignedFractScale() const {

    return PaddingOnUnsignedFixedPoint ? 
getFractScale()83
 : 
getFractScale() + 1919k
;

  }

  /// getUnsignedLongFractScale - Return the number of fractional bits

  /// in a 'unsigned long _Fract' type.

  unsigned getUnsignedLongFractScale() const {

    return PaddingOnUnsignedFixedPoint ? 
getLongFractScale()49

                                       : 
getLongFractScale() + 1735k
;

  }

  /// Determine whether the __int128 type is supported on this target.

  virtual bool hasInt128Type() const {

    return (getPointerWidth(0) >= 64) || 
getTargetOpts().ForceEnableInt12824.2k
;

  } // FIXME

  /// Determine whether _Float16 is supported on this target.

  virtual bool hasLegalHalfType() const { return HasLegalHalfType; }

  /// Determine whether the __float128 type is supported on this target.

  virtual bool hasFloat128Type() const { return HasFloat128; }

  /// Determine whether the _Float16 type is supported on this target.

  virtual bool hasFloat16Type() const { return HasFloat16; }

  /// Return the alignment that is suitable for storing any

  /// object with a fundamental alignment requirement.

  unsigned getSuitableAlign() const { return SuitableAlign; }

  /// Return the default alignment for __attribute__((aligned)) on

  /// this target, to be used if no alignment value is specified.

  unsigned getDefaultAlignForAttributeAligned() const {

    return DefaultAlignForAttributeAligned;

  }

  /// getMinGlobalAlign - Return the minimum alignment of a global variable,

  /// unless its alignment is explicitly reduced via attributes.

  virtual unsigned getMinGlobalAlign (uint64_t) const {

    return MinGlobalAlign;

  }

  /// Return the largest alignment for which a suitably-sized allocation with

  /// '::operator new(size_t)' is guaranteed to produce a correctly-aligned

  /// pointer.

  unsigned getNewAlign() const {

    return NewAlign ? 
NewAlign2.67k
 : 
std::max(LongDoubleAlign, LongLongAlign)66.5k
;

  }

  /// getWCharWidth/Align - Return the size of 'wchar_t' for this target, in

  /// bits.

  unsigned getWCharWidth() const { return getTypeWidth(WCharType); }

  unsigned getWCharAlign() const { return getTypeAlign(WCharType); }

  /// getChar16Width/Align - Return the size of 'char16_t' for this target, in

  /// bits.

  unsigned getChar16Width() const { return getTypeWidth(Char16Type); }

  unsigned getChar16Align() const { return getTypeAlign(Char16Type); }

  /// getChar32Width/Align - Return the size of 'char32_t' for this target, in

  /// bits.

  unsigned getChar32Width() const { return getTypeWidth(Char32Type); }

  unsigned getChar32Align() const { return getTypeAlign(Char32Type); }

  /// getHalfWidth/Align/Format - Return the size/align/format of 'half'.

  unsigned getHalfWidth() const { return HalfWidth; }

  unsigned getHalfAlign() const { return HalfAlign; }

  const llvm::fltSemantics &getHalfFormat() const { return *HalfFormat; }

  /// getFloatWidth/Align/Format - Return the size/align/format of 'float'.

  unsigned getFloatWidth() const { return FloatWidth; }

  unsigned getFloatAlign() const { return FloatAlign; }

  const llvm::fltSemantics &getFloatFormat() const { return *FloatFormat; }

  /// getDoubleWidth/Align/Format - Return the size/align/format of 'double'.

  unsigned getDoubleWidth() const { return DoubleWidth; }

  unsigned getDoubleAlign() const { return DoubleAlign; }

  const llvm::fltSemantics &getDoubleFormat() const { return *DoubleFormat; }

  /// getLongDoubleWidth/Align/Format - Return the size/align/format of 'long

  /// double'.

  unsigned getLongDoubleWidth() const { return LongDoubleWidth; }

  unsigned getLongDoubleAlign() const { return LongDoubleAlign; }

  const llvm::fltSemantics &getLongDoubleFormat() const {

    return *LongDoubleFormat;

  }

  /// getFloat128Width/Align/Format - Return the size/align/format of

  /// '__float128'.

  unsigned getFloat128Width() const { return 128; }

  unsigned getFloat128Align() const { return Float128Align; }

  const llvm::fltSemantics &getFloat128Format() const {

    return *Float128Format;

  }

  /// Return the mangled code of long double.

  virtual const char *getLongDoubleMangling() const { return "e"; }

  /// Return the mangled code of __float128.

  virtual const char *getFloat128Mangling() const { return "g"; }

  /// Return the value for the C99 FLT_EVAL_METHOD macro.

  virtual unsigned getFloatEvalMethod() const { return 0; }

  // getLargeArrayMinWidth/Align - Return the minimum array size that is

  // 'large' and its alignment.

  unsigned getLargeArrayMinWidth() const { return LargeArrayMinWidth; }

  unsigned getLargeArrayAlign() const { return LargeArrayAlign; }

  /// Return the maximum width lock-free atomic operation which will

  /// ever be supported for the given target

  unsigned getMaxAtomicPromoteWidth() const { return MaxAtomicPromoteWidth; }

  /// Return the maximum width lock-free atomic operation which can be

  /// inlined given the supported features of the given target.

  unsigned getMaxAtomicInlineWidth() const { return MaxAtomicInlineWidth; }

  /// Set the maximum inline or promote width lock-free atomic operation

  /// for the given target.

  virtual void setMaxAtomicWidth() {}

  /// Returns true if the given target supports lock-free atomic

  /// operations at the specified width and alignment.

  virtual bool hasBuiltinAtomic(uint64_t AtomicSizeInBits,

                                uint64_t AlignmentInBits) const {

    return AtomicSizeInBits <= AlignmentInBits &&

           
AtomicSizeInBits <= getMaxAtomicInlineWidth()1.99k
 &&

           
(1.83k
AtomicSizeInBits <= getCharWidth()1.83k
 ||

            
llvm::isPowerOf2_64(AtomicSizeInBits / getCharWidth())1.67k
);

  }

  /// Return the maximum vector alignment supported for the given target.

  unsigned getMaxVectorAlign() const { return MaxVectorAlign; }

  /// Return default simd alignment for the given target. Generally, this

  /// value is type-specific, but this alignment can be used for most of the

  /// types for the given target.

  unsigned getSimdDefaultAlign() const { return SimdDefaultAlign; }

  /// Return the alignment (in bits) of the thrown exception object. This is

  /// only meaningful for targets that allocate C++ exceptions in a system

  /// runtime, such as those using the Itanium C++ ABI.

  virtual unsigned getExnObjectAlignment() const {

    // Itanium says that an _Unwind_Exception has to be "double-word"

    // aligned (and thus the end of it is also so-aligned), meaning 16

    // bytes.  Of course, that was written for the actual Itanium,

    // which is a 64-bit platform.  Classically, the ABI doesn't really

    // specify the alignment on other platforms, but in practice

    // libUnwind declares the struct with __attribute__((aligned)), so

    // we assume that alignment here.  (It's generally 16 bytes, but

    // some targets overwrite it.)

    return getDefaultAlignForAttributeAligned();

  }

  /// Return the size of intmax_t and uintmax_t for this target, in bits.

  unsigned getIntMaxTWidth() const {

    return getTypeWidth(IntMaxType);

  }

  // Return the size of unwind_word for this target.

  virtual unsigned getUnwindWordWidth() const { return getPointerWidth(0); }

  /// Return the "preferred" register width on this target.

  virtual unsigned getRegisterWidth() const {

    // Currently we assume the register width on the target matches the pointer

    // width, we can introduce a new variable for this if/when some target wants

    // it.

    return PointerWidth;

  }

  /// Returns the name of the mcount instrumentation function.

  const char *getMCountName() const {

    return MCountName;

  }

  /// Check if the Objective-C built-in boolean type should be signed

  /// char.

  ///

  /// Otherwise, if this returns false, the normal built-in boolean type

  /// should also be used for Objective-C.

  bool useSignedCharForObjCBool() const {

    return UseSignedCharForObjCBool;

  }

  void noSignedCharForObjCBool() {

    UseSignedCharForObjCBool = false;

  }

  /// Check whether the alignment of bit-field types is respected

  /// when laying out structures.

  bool useBitFieldTypeAlignment() const {

    return UseBitFieldTypeAlignment;

  }

  /// Check whether zero length bitfields should force alignment of

  /// the next member.

  bool useZeroLengthBitfieldAlignment() const {

    return UseZeroLengthBitfieldAlignment;

  }

  /// Get the fixed alignment value in bits for a member that follows

  /// a zero length bitfield.

  unsigned getZeroLengthBitfieldBoundary() const {

    return ZeroLengthBitfieldBoundary;

  }

  /// Check whether explicit bitfield alignment attributes should be

  //  honored, as in "__attribute__((aligned(2))) int b : 1;".

  bool useExplicitBitFieldAlignment() const {

    return UseExplicitBitFieldAlignment;

  }

  /// Check whether this target support '\#pragma options align=mac68k'.

  bool hasAlignMac68kSupport() const {

    return HasAlignMac68kSupport;

  }

  /// Return the user string for the specified integer type enum.

  ///

  /// For example, SignedShort -> "short".

  static const char *getTypeName(IntType T);

  /// Return the constant suffix for the specified integer type enum.

  ///

  /// For example, SignedLong -> "L".

  const char *getTypeConstantSuffix(IntType T) const;

  /// Return the printf format modifier for the specified

  /// integer type enum.

  ///

  /// For example, SignedLong -> "l".

  static const char *getTypeFormatModifier(IntType T);

  /// Check whether the given real type should use the "fpret" flavor of

  /// Objective-C message passing on this target.

  bool useObjCFPRetForRealType(RealType T) const {

    return RealTypeUsesObjCFPRet & (1 << T);

  }

  /// Check whether _Complex long double should use the "fp2ret" flavor

  /// of Objective-C message passing on this target.

  bool useObjCFP2RetForComplexLongDouble() const {

    return ComplexLongDoubleUsesFP2Ret;

  }

  /// Check whether llvm intrinsics such as llvm.convert.to.fp16 should be used

  /// to convert to and from __fp16.

  /// FIXME: This function should be removed once all targets stop using the

  /// conversion intrinsics.

  virtual bool useFP16ConversionIntrinsics() const {

    return true;

  }

  /// Specify if mangling based on address space map should be used or

  /// not for language specific address spaces

  bool useAddressSpaceMapMangling() const {

    return UseAddrSpaceMapMangling;

  }

  ///===---- Other target property query methods --------------------------===//

  /// Appends the target-specific \#define values for this

  /// target set to the specified buffer.

  virtual void getTargetDefines(const LangOptions &Opts,

                                MacroBuilder &Builder) const = 0;

  /// Return information about target-specific builtins for

  /// the current primary target, and info about which builtins are non-portable

  /// across the current set of primary and secondary targets.

  virtual ArrayRef<Builtin::Info> getTargetBuiltins() const = 0;

  /// The __builtin_clz* and __builtin_ctz* built-in

  /// functions are specified to have undefined results for zero inputs, but

  /// on targets that support these operations in a way that provides

  /// well-defined results for zero without loss of performance, it is a good

  /// idea to avoid optimizing based on that undef behavior.

  virtual bool isCLZForZeroUndef() const { return true; }

  /// Returns the kind of __builtin_va_list type that should be used

  /// with this target.

  virtual BuiltinVaListKind getBuiltinVaListKind() const = 0;

  /// Returns whether or not type \c __builtin_ms_va_list type is

  /// available on this target.

  bool hasBuiltinMSVaList() const { return HasBuiltinMSVaList; }

  /// Returns true for RenderScript.

  bool isRenderScriptTarget() const { return IsRenderScriptTarget; }

  /// Returns whether or not the AArch64 SVE built-in types are

  /// available on this target.

  bool hasAArch64SVETypes() const { return HasAArch64SVETypes; }

  /// Returns whether the passed in string is a valid clobber in an

  /// inline asm statement.

  ///

  /// This is used by Sema.

  bool isValidClobber(StringRef Name) const;

  /// Returns whether the passed in string is a valid register name

  /// according to GCC.

  ///

  /// This is used by Sema for inline asm statements.

  virtual bool isValidGCCRegisterName(StringRef Name) const;

  /// Returns the "normalized" GCC register name.

  ///

  /// ReturnCannonical true will return the register name without any additions

  /// such as "{}" or "%" in it's canonical form, for example:

  /// ReturnCanonical = true and Name = "rax", will return "ax".

  StringRef getNormalizedGCCRegisterName(StringRef Name,

                                         bool ReturnCanonical = false) const;

  virtual bool isSPRegName(StringRef) const { return false; }

  /// Extracts a register from the passed constraint (if it is a

  /// single-register constraint) and the asm label expression related to a

  /// variable in the input or output list of an inline asm statement.

  ///

  /// This function is used by Sema in order to diagnose conflicts between

  /// the clobber list and the input/output lists.

  virtual StringRef getConstraintRegister(StringRef Constraint,

                                          StringRef Expression) const {

    return "";

  }

  struct ConstraintInfo {

    enum {

      CI_None = 0x00,

      CI_AllowsMemory = 0x01,

      CI_AllowsRegister = 0x02,

      CI_ReadWrite = 0x04,         // "+r" output constraint (read and write).

      CI_HasMatchingInput = 0x08,  // This output operand has a matching input.

      CI_ImmediateConstant = 0x10, // This operand must be an immediate constant

      CI_EarlyClobber = 0x20,      // "&" output constraint (early clobber).

    };

    unsigned Flags;

    int TiedOperand;

    struct {

      int Min;

      int Max;

      bool isConstrained;

    } ImmRange;

    llvm::SmallSet<int, 4> ImmSet;

    std::string ConstraintStr;  // constraint: "=rm"

    std::string Name;           // Operand name: [foo] with no []'s.

  public:

    ConstraintInfo(StringRef ConstraintStr, StringRef Name)

        : Flags(0), TiedOperand(-1), ConstraintStr(ConstraintStr.str()),

          Name(Name.str()) {

      ImmRange.Min = ImmRange.Max = 0;

      ImmRange.isConstrained = false;

    }

    const std::string &getConstraintStr() const { return ConstraintStr; }

    const std::string &getName() const { return Name; }

    bool isReadWrite() const { return (Flags & CI_ReadWrite) != 0; }

    bool earlyClobber() { return (Flags & CI_EarlyClobber) != 0; }

    bool allowsRegister() const { return (Flags & CI_AllowsRegister) != 0; }

    bool allowsMemory() const { return (Flags & CI_AllowsMemory) != 0; }

    /// Return true if this output operand has a matching

    /// (tied) input operand.

    bool hasMatchingInput() const { return (Flags & CI_HasMatchingInput) != 0; }

    /// Return true if this input operand is a matching

    /// constraint that ties it to an output operand.

    ///

    /// If this returns true then getTiedOperand will indicate which output

    /// operand this is tied to.

    bool hasTiedOperand() const { return TiedOperand != -1; }

    unsigned getTiedOperand() const {

      assert(hasTiedOperand() && "Has no tied operand!");

      return (unsigned)TiedOperand;

    }

    bool requiresImmediateConstant() const {

      return (Flags & CI_ImmediateConstant) != 0;

    }

    bool isValidAsmImmediate(const llvm::APInt &Value) const {

      if (!ImmSet.empty())

        return Value.isSignedIntN(32) &&

               
ImmSet.count(Value.getZExtValue()) != 024
;

      return !ImmRange.isConstrained ||

             
(122
Value.sge(ImmRange.Min)122
 && 
Value.sle(ImmRange.Max)95
);

    }

    void setIsReadWrite() { Flags |= CI_ReadWrite; }

    void setEarlyClobber() { Flags |= CI_EarlyClobber; }

    void setAllowsMemory() { Flags |= CI_AllowsMemory; }

    void setAllowsRegister() { Flags |= CI_AllowsRegister; }

    void setHasMatchingInput() { Flags |= CI_HasMatchingInput; }

    void setRequiresImmediate(int Min, int Max) {

      Flags |= CI_ImmediateConstant;

      ImmRange.Min = Min;

      ImmRange.Max = Max;

      ImmRange.isConstrained = true;

    }

    void setRequiresImmediate(llvm::ArrayRef<int> Exacts) {

      Flags |= CI_ImmediateConstant;

      for (int Exact : Exacts)

        ImmSet.insert(Exact);

    }

    void setRequiresImmediate(int Exact) {

      Flags |= CI_ImmediateConstant;

      ImmSet.insert(Exact);

    }

    void setRequiresImmediate() {

      Flags |= CI_ImmediateConstant;

    }

    /// Indicate that this is an input operand that is tied to

    /// the specified output operand.

    ///

    /// Copy over the various constraint information from the output.

    void setTiedOperand(unsigned N, ConstraintInfo &Output) {

      Output.setHasMatchingInput();

      Flags = Output.Flags;

      TiedOperand = N;

      // Don't copy Name or constraint string.

    }

  };

  /// Validate register name used for global register variables.

  ///

  /// This function returns true if the register passed in RegName can be used

  /// for global register variables on this target. In addition, it returns

  /// true in HasSizeMismatch if the size of the register doesn't match the

  /// variable size passed in RegSize.

  virtual bool validateGlobalRegisterVariable(StringRef RegName,

                                              unsigned RegSize,

                                              bool &HasSizeMismatch) const {

    HasSizeMismatch = false;

    return true;

  }

  // validateOutputConstraint, validateInputConstraint - Checks that

  // a constraint is valid and provides information about it.

  // FIXME: These should return a real error instead of just true/false.

  bool validateOutputConstraint(ConstraintInfo &Info) const;

  bool validateInputConstraint(MutableArrayRef<ConstraintInfo> OutputConstraints,

                               ConstraintInfo &info) const;

  virtual bool validateOutputSize(const llvm::StringMap<bool> &FeatureMap,

                                  StringRef /*Constraint*/,

                                  unsigned /*Size*/) const {

    return true;

  }

  virtual bool validateInputSize(const llvm::StringMap<bool> &FeatureMap,

                                 StringRef /*Constraint*/,

                                 unsigned /*Size*/) const {

    return true;

  }

  virtual bool

  validateConstraintModifier(StringRef /*Constraint*/,

                             char /*Modifier*/,

                             unsigned /*Size*/,

                             std::string &/*SuggestedModifier*/) const {

    return true;

  }

  virtual bool

  validateAsmConstraint(const char *&Name,

                        TargetInfo::ConstraintInfo &info) const = 0;

  bool resolveSymbolicName(const char *&Name,

                           ArrayRef<ConstraintInfo> OutputConstraints,

                           unsigned &Index) const;

  // Constraint parm will be left pointing at the last character of

  // the constraint.  In practice, it won't be changed unless the

  // constraint is longer than one character.

  virtual std::string convertConstraint(const char *&Constraint) const {

    // 'p' defaults to 'r', but can be overridden by targets.

    if (*Constraint == 'p')

      return std::string("r");

    return std::string(1, *Constraint);

  }

  /// Returns a string of target-specific clobbers, in LLVM format.

  virtual const char *getClobbers() const = 0;

  /// Returns true if NaN encoding is IEEE 754-2008.

  /// Only MIPS allows a different encoding.

  virtual bool isNan2008() const {

    return true;

  }

  /// Returns the target triple of the primary target.

  const llvm::Triple &getTriple() const {

    return Triple;

  }

  const llvm::DataLayout &getDataLayout() const {

    assert(DataLayout && "Uninitialized DataLayout!");

    return *DataLayout;

  }

  struct GCCRegAlias {

    const char * const Aliases[5];

    const char * const Register;

  };

  struct AddlRegName {

    const char * const Names[5];

    const unsigned RegNum;

  };

  /// Does this target support "protected" visibility?

  ///

  /// Any target which dynamic libraries will naturally support

  /// something like "default" (meaning that the symbol is visible

  /// outside this shared object) and "hidden" (meaning that it isn't)

  /// visibilities, but "protected" is really an ELF-specific concept

  /// with weird semantics designed around the convenience of dynamic

  /// linker implementations.  Which is not to suggest that there's

  /// consistent target-independent semantics for "default" visibility

  /// either; the entire thing is pretty badly mangled.

  virtual bool hasProtectedVisibility() const { return true; }

  /// An optional hook that targets can implement to perform semantic

  /// checking on attribute((section("foo"))) specifiers.

  ///

  /// In this case, "foo" is passed in to be checked.  If the section

  /// specifier is invalid, the backend should return a non-empty string

  /// that indicates the problem.

  ///

  /// This hook is a simple quality of implementation feature to catch errors

  /// and give good diagnostics in cases when the assembler or code generator

  /// would otherwise reject the section specifier.

  ///

  virtual std::string isValidSectionSpecifier(StringRef SR) const {

    return "";

  }

  /// Set forced language options.

  ///

  /// Apply changes to the target information with respect to certain

  /// language options which change the target configuration and adjust

  /// the language based on the target options where applicable.

  virtual void adjust(LangOptions &Opts);

  /// Adjust target options based on codegen options.

  virtual void adjustTargetOptions(const CodeGenOptions &CGOpts,

                                   TargetOptions &TargetOpts) const {}

  /// Initialize the map with the default set of target features for the

  /// CPU this should include all legal feature strings on the target.

  ///

  /// \return False on error (invalid features).

  virtual bool initFeatureMap(llvm::StringMap<bool> &Features,

                              DiagnosticsEngine &Diags, StringRef CPU,

                              const std::vector<std::string> &FeatureVec) const;

  /// Get the ABI currently in use.

  virtual StringRef getABI() const { return StringRef(); }

  /// Get the C++ ABI currently in use.

  TargetCXXABI getCXXABI() const {

    return TheCXXABI;

  }

  /// Target the specified CPU.

  ///

  /// \return  False on error (invalid CPU name).

  virtual bool setCPU(const std::string &Name) {

    return false;

  }